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Saturday, February 28, 2015

Intel



From Wikipedia, the free encyclopedia

Intel Corporation
Public
Traded as NASDAQINTC
Dow Jones Industrial Average Component
NASDAQ-100 Component
S&P 500 Component
Industry Semiconductors
Founded July 18, 1968 (1968-07-18)
Founder Gordon Moore, Robert Noyce
Headquarters Santa Clara, California, U.S.[1]
Area served
Worldwide
Key people
Andy Bryant
(Chairman)
Brian Krzanich
(CEO)
Renée James
(President)
Products Bluetooth chipsets, flash memory, microprocessors, motherboard chipsets, network interface cards, mobile phones
Revenue Increase US$ 55.870 billion (2014)[2]
Increase US$ 15.201 billion (2014)[2]
Increase US$ 11.704 billion (2014)[2]
Total assets Decrease US$ 91.956 billion (2014)[2]
Total equity Decrease US$ 55.865 billion (2014)[2]
Number of employees
106,700 (2014)[3]
Website www.intel.com

Intel Corporation is an American multinational corporation headquartered in Santa Clara, California. Intel is one of the world's largest and highest valued semiconductor chip makers, based on revenue.[4] It is the inventor of the x86 series of microprocessors, the processors found in most personal computers.

Intel Corporation, founded on July 18, 1968, is a portmanteau of Integrated Electronics (the fact that "intel" is the term for intelligence information also made the name appropriate).[5] Intel also makes motherboard chipsets, network interface controllers and integrated circuits, flash memory, graphic chips, embedded processors and other devices related to communications and computing. Founded by semiconductor pioneers Robert Noyce and Gordon Moore and widely associated with the executive leadership and vision of Andrew Grove, Intel combines advanced chip design capability with a leading-edge manufacturing capability. Though Intel was originally known primarily to engineers and technologists, its "Intel Inside" advertising campaign of the 1990s made it a household name, along with its Pentium processors.

Intel was an early developer of SRAM and DRAM memory chips, and this represented the majority of its business until 1981. Although Intel created the world's first commercial microprocessor chip in 1971, it was not until the success of the personal computer (PC) that this became its primary business. During the 1990s, Intel invested heavily in new microprocessor designs fostering the rapid growth of the computer industry. During this period Intel became the dominant supplier of microprocessors for PCs, and was known for aggressive and sometimes illegal tactics in defense of its market position, particularly against Advanced Micro Devices (AMD), as well as a struggle with Microsoft for control over the direction of the PC industry.[6][7]

The 2013 rankings of the world's 100 most valuable brands published by Millward Brown Optimor showed the company's brand value at number 61.[8]

Intel has also begun research into electrical transmission and generation.[9][10] Intel has recently introduced a 3-D transistor that improves performance and energy efficiency.[11] Intel has begun mass-producing this 3-D transistor, named the Tri-Gate transistor, with their 22 nm process, which is currently used in their 3rd generation core processors initially released on April 29, 2012.[12] In 2011, SpectraWatt Inc., a solar cell spinoff of Intel, filed for bankruptcy under Chapter 11.[13] In June 2013, Intel unveiled its fourth generation of Intel Core processors (Haswell) in an event named Computex in Taipei.[14]

The Open Source Technology Center at Intel hosts PowerTOP and LatencyTOP, and supports other open-source projects such as Wayland, Intel Array Building Blocks, Threading Building Blocks (TBB), and Xen.[15][16]

Corporate history

Origins


The old Intel logo used from July 18, 1968, until December 2005

Intel was originally founded in Mountain View, California in 1968 by Gordon E. Moore (of "Moore's Law" fame), a chemist, and Robert Noyce, a physicist and co-inventor of the integrated circuit. Arthur Rock (investor and venture capitalist) helped them find investors, while Max Palevsky was on the board from an early stage.[17] Moore and Noyce had left Fairchild Semiconductor to found Intel. Rock was not an employee, but he was an investor and was chairman of the board.[18][19] The total initial investment in Intel was $2.5 million convertible debentures and $10,000 from Rock. Just 2 years later, Intel completed their initial public offering (IPO), raising $6.8 million ($23.50 per share).[18] Intel's third employee was Andy Grove,[20] a chemical engineer, who later ran the company through much of the 1980s and the high-growth 1990s.

In deciding on a name, Moore and Noyce quickly rejected "Moore Noyce",[21] homophone for "more noise" – an ill-suited name for an electronics company, since noise in electronics is usually very undesirable and typically associated with bad interference. Instead they used the name NM Electronics before renaming their company Integrated Electronics or "Intel" for short.[22] Since "Intel" was already trademarked by the hotel chain Intelco, they had to buy the rights for the name.[18][23]

Early history

At its founding, Intel was distinguished by its ability to make semiconductors. Its first product, in 1969, was the 3101 Schottky TTL bipolar 64-bit static random-access memory (SRAM), which was nearly twice as fast as earlier Schottky diode implementations by Fairchild and the Electrotechnical Laboratory in Tsukuba, Japan.[24][25] In the same year Intel also produced the 3301 Schottky bipolar 1024-bit read-only memory (ROM)[26] and the first commercial metal–oxide–semiconductor field-effect transistor (MOSFET) silicon gate SRAM chip, the 256-bit 1101.[18][27][28] Intel's business grew during the 1970s as it expanded and improved its manufacturing processes and produced a wider range of products, still dominated by various memory devices.

Federico Faggin, the designer of Intel 4004.

While Intel created the first commercially available microprocessor (Intel 4004) in 1971[18] and one of the first microcomputers in 1972,[27][29] by the early 1980s its business was dominated by dynamic random-access memory chips. However, increased competition from Japanese semiconductor manufacturers had, by 1983, dramatically reduced the profitability of this market. The growing success of the IBM personal computer, based on an Intel microprocessor, was among factors that convinced Gordon Moore (CEO since 1975) to shift the company's focus to microprocessors, and to change fundamental aspects of that business model. Moore's decision to sole-source Intel's 386 chip played into the company's continuing success.

By the end of the 1980s, buoyed by its fortuitous position as microprocessor supplier to IBM and IBM's competitors within the rapidly growing personal computer market, Intel embarked on a 10-year period of unprecedented growth as the primary (and most profitable) hardware supplier to the PC industry, part of the winning 'Wintel' combination. Moore handed over to Andy Grove in 1987. By launching its Intel Inside marketing campaign in 1991, Intel was able to associate brand loyalty with consumer selection, so that by the end of the 1990s, its line of Pentium processors had become a household name.

Slowing demand and challenges to dominance

After 2000, growth in demand for high-end microprocessors slowed. Competitors, notably AMD (Intel's largest competitor in its primary x86 architecture market), garnered significant market share, initially in low-end and mid-range processors but ultimately across the product range, and Intel's dominant position in its core market was greatly reduced.[30] In the early 2000s then-CEO Craig Barrett attempted to diversify the company's business beyond semiconductors, but few of these activities were ultimately successful.

Intel had also for a number of years been embroiled in litigation. US law did not initially recognize intellectual property rights related to microprocessor topology (circuit layouts), until the Semiconductor Chip Protection Act of 1984, a law sought by Intel and the Semiconductor Industry Association (SIA).[31] During the late 1980s and 1990s (after this law was passed), Intel also sued companies that tried to develop competitor chips to the 80386 CPU.[32] The lawsuits were noted to significantly burden the competition with legal bills, even if Intel lost the suits.[32] Antitrust allegations had been simmering since the early 1990s and had been the cause of one lawsuit against Intel in 1991. In 2004 and 2005, AMD brought further claims against Intel related to unfair competition.

In 2005, CEO Paul Otellini reorganized the company to refocus its core processor and chipset business on platforms (enterprise, digital home, digital health, and mobility). In 2013, Intel partnered with Medopad, an enterprise mobile health solution provider to support the deployment of Medopad across the 60+ BMI Healthcare hospitals.[33]

Regaining of momentum

In 2007, Intel unveiled its Core microarchitecture to widespread critical acclaim;[34] the product range was perceived as an exceptional leap in processor performance that at a stroke regained much of its leadership of the field.[35][36] In 2008, Intel had another "tick," when it introduced the Penryn microarchitecture, which was 45 nm. Later that year, Intel released a processor with the Nehalem architecture. Nehalem had positive reviews.[37]

Sale of XScale processor business

On June 27, 2006, the sale of Intel's XScale assets was announced. Intel agreed to sell the XScale processor business to Marvell Technology Group for an estimated $600 million and the assumption of unspecified liabilities. The move was intended to permit Intel to focus its resources on its core x86 and server businesses, and the acquisition completed on November 9, 2006.[38]

Acquisitions

On August 19, 2010, Intel announced that it planned to purchase McAfee, a manufacturer of computer security technology. The purchase price was $7.68 billion, and the companies said that if the deal were approved, new products would be released early in 2011.[39] On January 26, 2011, the European Union approved the acquisition, after Intel agreed to provide rival security firms with all necessary information that would allow their products to use Intel's chips and personal computers.[40] After the acquisition, Intel had about 90,000 employees, including about 12,000 software engineers.[41]

On August 30, 2010, Intel and Infineon Technologies announced that Intel would acquire Infineon's Wireless Solutions business.[42] Intel planned to use Infineon's technology in laptops, smart phones, netbooks, tablets and embedded computers in consumer products, eventually integrating its wireless modem into Intel's silicon chips.[43]

In March 2011, Intel bought most of the assets of Cairo-based SySDSoft.[44]

In July 2011, Intel announced that it had agreed to acquire Fulcrum Microsystems Inc., a company specializing in network switches.[45] The company was previously included on the EE Times list of 60 Emerging Startups.[45]

On October 1, 2011, Intel reached a deal to acquire Telmap, an Israeli-based navigation software company. The purchase price was not disclosed, but Israeli media reported values around $300 million to $350 million.[46]

In July 2012, Intel Corporation agreed to buy 10 percent shares of ASML Holding NV for $2.1 billion and another $1 billon for 5 percent shares that need shareholder approval to fund relevant research and development efforts, as part of a EUR3.3 billion ($4.1 billion) deal to accelerate the development of 450-millimeter wafer technology and extreme ultra-violet lithography by as much as two years.[47]

In July 2013, Intel confirmed the acquisition of Omek Interactive, an Israeli company that makes technology for gesture-based interfaces, without disclosing the monetary value of the deal. An official statement from Intel read: "The acquisition of Omek Interactive will help increase Intel's capabilities in the delivery of more immersive perceptual computing experiences." One report estimated the value of the acquisition between US$30 million and $50 million.[48]

The acquisition of a Spanish natural language recognition startup named Indisys was announced on September 13, 2013. The terms of the deal were not disclosed but an email from an Intel representative stated: "Intel has acquired Indisys, a privately held company based in Seville, Spain. The majority of Indisys employees joined Intel. We signed the agreement to acquire the company on May 31 and the deal has been completed." Indysis explains that its artificial intelligence (AI) technology "is a human image, which converses fluently and with common sense in multiple languages and also works in different platforms."[49]

In December 2014, Intel bought PasswordBox.[50]

In January 2015, Intel purchased a 30% stake in Vuzix, a smart glasses manufacturer. The deal was worth $24.8 million.[51]

In February 2015, Intel announced its agreement to purchase German network chipmaker Lantiq, to aid in its expansion of its range of chips in devices with Internet connection capability.[52]

Acquisition table

Number Acquisition date Company Business Country Price Used as or integrated with Ref(s).
1 June 4, 2009 Wind River Systems Embedded Systems  USA $884M Software [53]
2 August 19, 2010 McAfee Security  USA $7.6B Software [54]
3 August 30, 2010 Infineon Wireless  Germany $1.4B Mobile CPUs [55]
4 March 17, 2011 Silicon Hive DSP  Netherlands N/A Mobile CPUs [56]
5 September 29, 2011 Telmap Software  Israel N/A Location Services [57]
6 April 13, 2013 Mashery Cloud Software  USA $180M Software [58]
7 May 3, 2013 Aepona SDN  Ireland N/A Software [59]
8 May 6, 2013 Stonesoft Corporation Security  Finland $389M Software [60]
9 July 16, 2013 Omek Interactive Gesture  Israel N/A Software [48]
10 September 13, 2013 Indisys Natural language processing  Spain N/A Software [49]
11 March 25, 2014 BASIS Wearable  USA N/A New Devices [61]
12 August 13, 2014 Avago Technologies Semiconductor  USA N/A Communications Processors [62]
13 December 1, 2014 PasswordBox Security  Canada N/A Software [63]
14 January 5, 2015 Vuzix Wearable  USA $24.8M New Devices [64]

Expansions

In 2008, Intel spun off key assets of a solar startup business effort to form an independent company, SpectraWatt Inc. However, as of 2011, SpectraWatt has filed for bankruptcy.[13]

In February 2011, Intel announced plans to build a new microprocessor manufacturing facility in Chandler, Arizona, which is expected to be completed in 2013, at a cost of $5 billion.[65] It will accommodate 4,000 employees. The company produces three-quarters of their products in the United States, although three-quarters of their revenue comes from overseas.[66]

In April 2011, Intel began a pilot project with ZTE Corporation to produce smartphones using the Intel Atom processor for China's domestic market. This project is intended to challenge the domination of ARM processors in mobile phones.[67]

In December 2011, Intel announced that it reorganized several of its business units to form a new mobile and communications group.[68] This group will be responsible for the company's smartphone, tablet and wireless efforts, and will be headed by Hermann Eul and Mike Bell.

Opening up the foundries

Finding itself with excess fab capacity after the failure of the Ultrabook to gain market traction and with PC sales declining, in 2013 Intel reached a foundry agreement to produce chips for Altera using 14-nm process. General Manager of Intel's custom foundry division Sunit Rikhi indicated that Intel would pursue further such deals in the future.[69] This was after poor sales of Windows 8 hardware caused a major retrenchment for most of the major semiconductor manufacturers, except for Qualcomm, which continued to see healthy purchases from its largest customer, Apple.[70]

As of July 2013, five companies will use Intel's fabs via the Intel Custom Foundry division: Achronix, Tabula, Netronome, Microsemi, and Altera—most are FPGA makers, but Netronome designs network processors. Only Achronix began shipping chips made by Intel using the 22-nm Tri-Gate process.[71][72] Several other customers also exist but were not announced at the time.[73]

The Alliance for Affordable Internet (A4AI) was launched in October 2013 and Intel is part of the coalition of public and private organisations that also includes Facebook, Google, and Microsoft. Led by Sir Tim Berners-Lee, the A4AI seeks to make Internet access more affordable so that access is broadened in the developing world, where only 31% of people are online. Google will help to decrease internet access prices so that they fall below the UN Broadband Commission's worldwide target of 5% of monthly income.[74]

Product and market history

SRAMS and the microprocessor

Intel's first products were shift register memory and random-access memory integrated circuits, and Intel grew to be a leader in the fiercely competitive DRAM, SRAM, and ROM markets throughout the 1970s. Concurrently, Intel engineers Marcian Hoff, Federico Faggin, Stanley Mazor and Masatoshi Shima invented Intel's first microprocessor. Originally developed for the Japanese company Busicom to replace a number of ASICs in a calculator already produced by Busicom, the Intel 4004 was introduced to the mass market on November 15, 1971, though the microprocessor did not become the core of Intel's business until the mid-1980s. (Note: Intel is usually given credit with Texas Instruments for the almost-simultaneous invention of the microprocessor)

From DRAM to microprocessors

In 1983, at the dawn of the personal computer era, Intel's profits came under increased pressure from Japanese memory-chip manufacturers, and then-president Andy Grove focused the company on microprocessors. Grove described this transition in the book Only the Paranoid Survive. A key element of his plan was the notion, then considered radical, of becoming the single source for successors to the popular 8086 microprocessor.

Until then, the manufacture of complex integrated circuits was not reliable enough for customers to depend on a single supplier,[clarification needed] but Grove began producing processors in three geographically distinct factories,[which?] and ceased licensing the chip designs to competitors such as Zilog and AMD.[citation needed] When the PC industry boomed in the late 1980s and 1990s, Intel was one of the primary beneficiaries.

Intel, x86 processors, and the IBM PC


The die from an Intel 8742, an 8-bit microcontroller that includes a CPU running at 12 MHz, 128 bytes of RAM, 2048 bytes of EPROM, and I/O in the same chip.

Despite the ultimate importance of the microprocessor, the 4004 and its successors the 8008 and the 8080 were never major revenue contributors at Intel. As the next processor, the 8086 (and its variant the 8088) was completed in 1978, Intel embarked on a major marketing and sales campaign for that chip nicknamed "Operation Crush", and intended to win as many customers for the processor as possible. One design win was the newly created IBM PC division, though the importance of this was not fully realized at the time.

IBM introduced its personal computer in 1981, and it was rapidly successful. In 1982, Intel created the 80286 microprocessor, which, two years later, was used in the IBM PC/AT. Compaq, the first IBM PC "clone" manufacturer, produced a desktop system based on the faster 80286 processor in 1985 and in 1986 quickly followed with the first 80386-based system, beating IBM and establishing a competitive market for PC-compatible systems and setting up Intel as a key component supplier.

In 1975, the company had started a project to develop a highly advanced 32-bit microprocessor, finally released in 1981 as the Intel iAPX 432. The project was too ambitious and the processor was never able to meet its performance objectives, and it failed in the marketplace. Intel extended the x86 architecture to 32 bits instead.[75][76]

386 microprocessor

During this period Andrew Grove dramatically redirected the company, closing much of its DRAM business and directing resources to the microprocessor business. Of perhaps greater importance was his decision to "single-source" the 386 microprocessor. Prior to this, microprocessor manufacturing was in its infancy, and manufacturing problems frequently reduced or stopped production, interrupting supplies to customers. To mitigate this risk, these customers typically insisted that multiple manufacturers produce chips they could use to ensure a consistent supply. The 8080 and 8086-series microprocessors were produced by several companies, notably AMD. Grove made the decision not to license the 386 design to other manufacturers, instead producing it in three geographically distinct factories: Santa Clara, California; Hillsboro, Oregon; and Chandler, a suburb of Phoenix, Arizona. He convinced customers that this would ensure consistent delivery. As the success of Compaq's Deskpro 386 established the 386 as the dominant CPU choice, Intel achieved a position of near-exclusive dominance as its supplier. Profits from this funded rapid development of both higher-performance chip designs and higher-performance manufacturing capabilities, propelling Intel to a position of unquestioned leadership by the early 1990s.

486, Pentium, and Itanium

Intel introduced the 486 microprocessor in 1989, and in 1990 formally established a second design team, designing the processors code-named "P5" and "P6" in parallel and committing to a major new processor every two years, versus the four or more years such designs had previously taken.
Engineers Vinod Dham and Rajeev Chandrasekhar (Member of Parliament, India) were key figures on the core team that invented the 486 chip and later, Intel's signature Pentium chip. The P5 was earlier known as "Operation Bicycle," referring to the cycles of the processor. The P5 was introduced in 1993 as the Intel Pentium, substituting a registered trademark name for the former part number (numbers, such as 486, are hard to register as a trademark). The P6 followed in 1995 as the Pentium Pro and improved into the Pentium II in 1997. New architectures were developed alternately in Santa Clara, California and Hillsboro, Oregon.

The Santa Clara design team embarked in 1993 on a successor to the x86 architecture, codenamed "P7". The first attempt was dropped a year later, but quickly revived in a cooperative program with Hewlett-Packard engineers, though Intel soon took over primary design responsibility. The resulting implementation of the IA-64 64-bit architecture was the Itanium, finally introduced in June 2001. The Itanium's performance running legacy x86 code did not meet expectations, and it failed to compete effectively with x86-64, which was AMD's 64-bit extensions to the original x86 architecture (Intel uses the name Intel 64, previously EM64T). As of 2012, Intel continues to develop and deploy the Itanium; known planning continues into 2014.

The Hillsboro team designed the Willamette processors (initially code-named P68), which were marketed as the Pentium 4.[citation needed]

Pentium flaw

In June 1994, Intel engineers discovered a flaw in the floating-point math subsection of the P5 Pentium microprocessor. Under certain data-dependent conditions, the low-order bits of the result of a floating-point division would be incorrect. The error could compound in subsequent calculations. Intel corrected the error in a future chip revision.
In October 1994, Thomas Nicely, Professor of Mathematics at Lynchburg College, independently discovered the bug. He contacted Intel, but received no response. On October 30, he posted a message on the Internet.[77] Word of the bug spread quickly and reached the industry press. The bug was easy to replicate; a user could enter specific numbers into the calculator on the operating system. Consequently, many users did not accept Intel's statements that the error was minor and "not even an erratum." During Thanksgiving, in 1994, The New York Times ran a piece by journalist John Markoff spotlighting the error. Intel changed its position and offered to replace every chip, quickly putting in place a large end-user support organization. This resulted in a $500 million charge against Intel's 1994 revenue.

The "Pentium flaw" incident, Intel's response to it, and the surrounding media coverage propelled Intel from being a technology supplier generally unknown to most computer users to a household name. Dovetailing with an uptick in the "Intel Inside" campaign, the episode is considered to have been a positive event for Intel, changing some of its business practices to be more end-user focused and generating substantial public awareness, while avoiding a lasting negative impression.[78]

"Intel Inside" and other 1990s programs

During this period, Intel undertook two major supporting programs. The first is widely known: the 1991 "Intel Inside" marketing and branding campaign. The idea of ingredient branding was new at the time with only Nutrasweet and a few others making attempts to do so.[79] This campaign established Intel, which had been a component supplier little-known outside the PC industry, as a household name.

The second program is little-known: Intel's Systems Group began, in the early 1990s, manufacturing PC "motherboards", the main board component of a personal computer, and the one into which the processor (CPU) and memory (RAM) chips are plugged.[80] Shortly after, Intel began manufacturing fully configured "white box" systems for the dozens of PC clone companies that rapidly sprang up.[citation needed] At its peak in the mid-1990s, Intel manufactured over 15% of all PCs, making it the third-largest supplier at the time.[citation needed]

During the 1990s, Intel's Architecture Lab (IAL) was responsible for many of the hardware innovations of the personal computer, including the PCI Bus, the PCI Express (PCIe) bus, the Universal Serial Bus (USB). IAL's software efforts met with a more mixed fate; its video and graphics software was important in the development of software digital video,[citation needed] but later its efforts were largely overshadowed by competition from Microsoft. The competition between Intel and Microsoft was revealed in testimony by IAL Vice-President Steven McGeady at the Microsoft antitrust trial.

Solid-state drives (SSD)


An Intel X25-M SSD

On September 8, 2008, Intel began shipping its first mainstream solid-state drives, the X18-M and X25-M with 80GB and 160GB storage capacities.[81] Reviews measured high performance with these MLC-based drives.[82][83][84][85] Intel released their SLC-based Enterprise X25-E Extreme SSDs on October 15 that same year in capacities of 32GB and 64GB.[86]

In July 2009, Intel refreshed their X25-M and X18-M lines by moving from a 50-nanometer to a 34-nanometer process. These new drives, dubbed by the press as the X25-M and X18-M G2[87][88] (or generation 2), reduced prices by up to 60 percent while offering lower latency and improved performance.[89]

On February 1, 2010, Intel and Micron announced that they were gearing up for production of NAND flash memory using a new 25-nanometer process.[90] In March of that same year, Intel entered the budget SSD segment with their X25-V drives with an initial capacity of 40GB.[91] The SSD 310, Intel's first mSATA drive was released on December 2010, providing X25-M G2 performance in a much smaller package.[92][93]

March 2011 saw the introduction of two new SSD lines from Intel. The first, the SSD 510, used a SATA 6 Gigabit per second interface to reach speeds of up to 500 MegaBytes per second.[94] The drive, which uses a controller from Marvell Technology Group,[95] was released using 34 nm NAND Flash and came in capacities of 120GB and 250GB. The second product announcement, the SSD 320, is the successor to Intel's earlier X25-M. It uses the new 25 nm process that Intel and Micron announced in 2010, and was released in capacities of 40 GB, 80 GB, 120 GB, 160 GB, 300 GB and 600 GB.[96] Sequential read performance maxes out at 270 MB/s due to the older SATA 3 Gbit/s interface, and sequential write performance varies greatly based on the size of the drive with sequential write performance of the 40 GB model peaking at 45 MB/s and the 600 GB at 220 MB/s.[97]

Micron and Intel announced that they were producing their first 20 nm MLC NAND flash on April 14, 2011.[98]

In February 2012, Intel launched the SSD 520 series solid state drives using the SandForce SF-2200 controller with sequential read and write speeds of 550 and 520 MB/s respectively with random read and write IOPS as high as 80,000. These drives will replace the 510 series.[99] Intel has released the budget 330 series solid state drive in 60, 120, and 180GB capacities using 25 nm flash memory and a SandForce controller that have replaced the 320 series.[100][101]
Intel SSDs
Model Codename Capacities (GB) NAND type Interface Form factor Controller Seq. read/write MB/s Rnd 4KB read/write IOPS (K) Introduced Comment / Source
X18-M/X25-M Ephraim 80/160 50 nm MLC SATA 3 Gbit/s 1.8"/2.5" Intel 250 / 70 35 / 3.300–0.35 Sept 2008 (now EOL) [81][102]
X25-E Ephraim 32/64 50 nm SLC SATA 3 Gbit/s 2.5" Intel 250 / 170 35 / 3.3 Oct 2008 [86][88]
X18-M G2 / X25-M G2 Postville 80/120/160 34 nm MLC SATA 3 Gbit/s 1.8"/2.5" Intel 250 / 100 35 / 6.6–0.3 July 2009 [87][88][103]
X25-V Glenbrook 40 34 nm MLC SATA 3 Gbit/s 2.5" Intel 170 / 35 25 / 2.5–? Mar 2010 [91][104]
310 Soda Creek 40/80 34 nm MLC SATA 3 Gbit/s mSATA Intel 200/70 35/2.6 Dec 2010 [92][105][106]
510 Elmcrest 120/250 34 nm MLC SATA 6 Gbit/s 2.5" Marvell 500/315 20/8 Mar 2011 [94][107]
320 Postville Refresh 40/80/120/160/300/600 25 nm MLC SATA 3 Gbit/s 1.8"/2.5" Intel[108] 270/220 39.5/23 Mar 2011 Originally to be released Oct 2010, named X18-M G3 & X25-M G3, the 1.8" was released later in 2011[88][96][109]
311 Larsen Creek 20 34 nm SLC SATA 3 Gbit/s 2.5"/mSATA Intel 200/105 37/3.3 May 2011 Special low capacity SLC SSD for use with Intel SRT[110][111][112]
710 Lyndonville 100/200/300 25 nm MLC-HET SATA 3 Gbit/s 2.5" Intel 270/210 38.5/2.7 Q3 2011 [113][114]
520 Cherryville 60/120/180/240/480 25 nm MLC SATA 6 Gbit/s 2.5" SandForce 550/520 50/80 February 2012 Replaces 510[99]
313 Hawley Creek 20/24 25 nm SLC SATA 3 Gbit/s 2.5"/mSATA Intel 220/115 36/4 April 2012 Replaces 311; for use with SRT[115]
330 Maple Crest 60/120/180/240 25 nm MLC SATA 6 Gbit/s 2.5" SandForce 500/450 22.5/33 April 2012 [100][101]
910 Ramsdale 400/800 25 nm MLC-HET PCIe 2.0 × 8 PCIe Intel/Hitachi 2000/1000 180/75 April 2012 [116][117]
335 Jay Crest 80/180/240 20 nm MLC SATA 6 Gbit/s 2.5" SandForce 500/450 42/52 October 2012 [118][119]
DC S3700 Taylorsville 100/200/400/800 25 nm MLC-HET SATA 6 Gbit/s 1.8"/2.5" Intel 500/450 72/34 November 2012 [120][121]
525 Lincoln Crest 30/60/120/180/240 25 nm MLC SATA 6 Gbit/s mSATA SandForce 550/520 50/60 January 2013 [122][123]
DC S3500 Wolfsville 80/120/160/240/300/400/480/600/800 20 nm MLC SATA 6 Gbit/s 1.8"/2.5" Intel 475/450 75/11.5 June 2013 [124][125]
530 Dale Crest 80/120/180/240/360/480 20 nm MLC SATA 6 Gbit/s M.2/mSATA/2.5" SandForce 540/490 41/80 July 2013 [126][127]
Pro 1500 Sierra Star 80/120/180/240/360/480 20 nm MLC SATA 6 Gbit/s M.2/2.5" SandForce 540/490 41/80 Sept 2013 [128][129][130]
Pro 2500 Temple Star 80/180/240/360/480 20 nm MLC SATA 6 Gbit/s M.2/2.5" SandForce? 540/490 42/52 Q2 2014 [131][132]
DC P3700 Fultondale 200/400/800/1600/2000 20 nm MLC-HET PCIe (2.5"/AIC) Intel 2800/1700 450/150 Q2 2014 Custom Intel NVMe controller[131][132]
DC P3500 Pleasantdale 250/500/1000/2000 20 nm MLC PCIe (2.5"/AIC) Intel 2800/1700 450/40 Q2 2014 Custom Intel NVMe controller[131][132]
730 Jackson Ridge 240/480 20 nm MLC SATA 6 Gbit/s 2.5" Intel 550/470 89/74 March 2014 [133]
DC P3600 400/800/1200/1600/2000 20 nm MLC PCIe (2.5"/AIC) Intel 2600/1700 450/56 June 2014 [134][135]
Model Codename Capacities (GB) NAND type Interface Form factor Controller Seq. read/write MB/s Rnd 4KB read/write IOPS (K) Introduced Comment / Source

Supercomputers

The Intel Scientific Computers division was founded in 1984 by Justin Rattner, in order to design and produce parallel computers based on Intel microprocessors connected in hypercube topologies.[136] In 1992 the name was changed to the Intel Supercomputing Systems Division, and development of the iWarp architecture was also subsumed.[137] The division designed several supercomputer systems, including the Intel iPSC/1, iPSC/2, iPSC/860, Paragon and ASCI Red. In November 2014, Intel revealed that it is going to use light beams to speed up supercomputers.[138] The renowned chip maker has also disclosed that all its Supercomputer forms will use optical technology for data transfer from 2015.

Competition, antitrust and espionage

Two factors combined to end this dominance: the slowing of PC demand growth beginning in 2000 and the rise of the low cost PC. By the end of the 1990s, microprocessor performance had outstripped software demand for that CPU power. Aside from high-end server systems and software, whose demand dropped with the end of the "dot-com bubble", consumer systems ran effectively on increasingly low-cost systems after 2000. Intel's strategy of producing ever-more-powerful processors and obsoleting their predecessors stumbled,[citation needed] leaving an opportunity for rapid gains by competitors, notably AMD. This in turn lowered the profitability[citation needed] of the processor line and ended an era of unprecedented dominance of the PC hardware by Intel.[citation needed]
Intel's dominance in the x86 microprocessor market led to numerous charges of antitrust violations over the years, including FTC investigations in both the late 1980s and in 1999, and civil actions such as the 1997 suit by Digital Equipment Corporation (DEC) and a patent suit by Intergraph. Intel's market dominance (at one time[when?] it controlled over 85% of the market for 32-bit x86 microprocessors) combined with Intel's own hardball legal tactics (such as its infamous 338 patent suit versus PC manufacturers)[139] made it an attractive target for litigation, but few of the lawsuits ever amounted to anything.[clarification needed]

A case of industrial espionage arose in 1995 that involved both Intel and AMD. Bill Gaede, an Argentine formerly employed both at AMD and at Intel's Arizona plant, was arrested for attempting in 1993 to sell the i486 and P5 Pentium designs to AMD and to certain foreign powers.[140] Gaede videotaped data from his computer screen at Intel and mailed it to AMD, which immediately alerted Intel and authorities, resulting in Gaede's arrest. Gaede was convicted and sentenced to 33 months in prison in June 1996.[141][142]

Partnership with Apple

On June 6, 2005, Steve Jobs, then CEO of Apple, announced that Apple would be transitioning from its long favored PowerPC architecture to the Intel x86 architecture, because the future PowerPC road map was unable to satisfy Apple's needs. The first Macintosh computers containing Intel CPUs were announced on January 10, 2006, and Apple had its entire line of consumer Macs running on Intel processors by early August 2006. The Apple Xserve server was updated to Intel Xeon processors from November 2006, and was offered in a configuration similar to Apple's Mac Pro.[143]

Core 2 Duo advertisement controversy

In 2007, the company released a print advertisement for its Core 2 Duo processor featuring six African American runners appearing to bow down to a Caucasian male inside of an office setting (due to the posture taken by runners on starting blocks). According to Nancy Bhagat, Vice President of Intel Corporate Marketing, the general public[clarification needed] found the ad to be "insensitive and insulting."[144] The campaign was quickly pulled and several Intel executives made public apologies on the corporate website.[145]

Classmate PC

Intel's Classmate PC is the company's first low-cost netbook computer.[146] One of the models, designed by TEAMS Design [4] in their Shanghai office, won many design awards, such as the Appliance Design EID Award,[147] the 2008 Spark Award,[148] and the iF 2008 China Award.[149]

Mobile processor

In June 2011, Intel introduced the first Pentium mobile processor based on the Sandy Bridge core. The B940, clocked at 2 GHz, is faster than existing or upcoming mobile Celerons, although it is almost identical to dual-core Celeron CPUs in all other aspects.[150] According to IHS iSuppli's report on September 28, 2011, Sandy Bridge chips have helped Intel increase its market share in global processor market to 81.8%, while AMD's market share dropped to 10.4%.[151]

Intel planned to introduce Medfield – a processor for tablets and smartphones – to the market in 2012, as an effort to compete with ARM.[152] As a 32-nanometer processor, Medfield is designed to be energy-efficient, which is one of the core features in ARM's chips.[153]

At the Intel Developers Forum (IDF) 2011 in San Francisco, Intel's partnership with Google was announced. By January 2012, Google's Android 2.3 will use Intel's Atom microprocessor.[154][155][156]

Server chips

In July 2011, Intel announced that its server chips, the Xeon series, will use new sensors that can improve data center cooling efficiency.[157]

22 nm processors

In 2011, Intel announced the Ivy Bridge processor family at the Intel Developer Forum.[158] Ivy Bridge supports both DDR3 memory and DDR3L chips.

Personal Office Energy Monitor (POEM)

As part of its efforts in the Positive Energy Buildings Consortium, Intel has been developing an application, called Personal Office Energy Monitor (POEM), to help office buildings to be more energy-efficient. With this application, employees can get the power consumption info for their office machines, so that they can figure out a better way to save energy in their working environment.[159]

IT Manager 3: Unseen Forces

IT Manager III: Unseen Forces is a web-based IT simulation game from Intel. In it you manage a company's IT department. The goal is to apply technology and skill to enable the company to grow from a small business into a global enterprise.[citation needed]

Car Security System

In 2011, Intel announced that it is working on a car security system that connects to smartphones via an application. The application works by streaming video to a cloud service if your car is broken into.[160]

High-Bandwidth Digital Content Protection

Intel also developed High-Bandwidth Digital Content Protection (HDCP) to prevent access of digital audio and video content as it travels across connections.

Move from Wintel desktop to open mobile platforms

In 2013, Intel's Kirk Skaugen said that Intel's exclusive focus on Microsoft platforms was a thing of the past and that they would now support all "tier-one operating systems" such as Linux, Android, iOS, and Chrome.[161]

In 2014, Intel cut thousands of employees in response to "evolving market trends",[162] and offered to subsidize manufacturers for the extra costs involved in using Intel chips in their tablets.[163]

Wearable fashion

On January 6, 2014, Intel announced that it was "teaming with the Council of Fashion Designers of America, Barneys New York and Opening Ceremony around the wearable tech field."[164]

Intel has developed a reference design for wearable smart earbuds that provide biometric and fitness information. The Intel smart earbuds provide full stereo audio, and monitor heart rate, while the applications on the user’s phone keep track of run distance and calories burned.

Corporate affairs

In September 2006, Intel had nearly 100,000 employees and 200 facilities world wide. Its 2005 revenues were $38.8 billion and its Fortune 500 ranking was 49th. Its stock symbol is INTC, listed on the NASDAQ. As of February 2009, the biggest customers of Intel are Hewlett-Packard and Dell.[165]

Leadership and corporate structure


Paul Otellini, Craig Barrett and Sean Maloney (2006)

Robert Noyce was Intel's CEO at its founding in 1968, followed by co-founder Gordon Moore in 1975. Andy Grove became the company's president in 1979 and added the CEO title in 1987 when Moore became chairman. In 1998, Grove succeeded Moore as Chairman, and Craig Barrett, already company president, took over. On May 18, 2005, Barrett handed the reins of the company over to Paul Otellini, who previously was the company president and COO and who was responsible for Intel's design win in the original IBM PC. The board of directors elected Otellini as President and CEO, and Barrett replaced Grove as Chairman of the Board. Grove stepped down as chairman, but is retained as a special adviser. In May 2009, Barrett stepped down as chairman of the Board and was succeeded by Jane Shaw. In May 2012, Intel vice chairman Andy Bryant, who had previously held the posts of CFO (1994) and Chief Administrative Officer (2007) at Intel, succeeded Shaw as executive chairman.[166]

In November 2012, president and CEO Paul Otellini announced that he would step down in May 2013 at the age of 62, three years before the company's mandatory retirement age. During a six-month transition period, Intel's board of directors commenced a search process for the next CEO, in which it considered both internal managers and external candidates such as Sanjay Jha and Patrick Gelsinger.[167] Financial results revealed that, under Otellini, Intel's revenue increased by 55.8 percent (US$34.2 to 53.3 billion), while its net income increased by 46.7% (US$7.5 billion to 11 billion).[168]

On May 2, 2013, Executive Vice President and COO Brian Krzanich was elected as Intel's sixth CEO,[169] a selection that became effective on May 16, 2013 at the company's annual meeting. Reportedly, the board concluded that an insider could proceed with the role and exert an impact more quickly, without the need to learn Intel's processes, and Krzanich was selected on such a basis.[170] Intel's software head Renée James was selected as president of the company, a role that is second to the CEO position.[171]

As of May 2013, Intel's board of directors consists of Andy Bryant, John Donahoe, Frank Yeary, Ambassador Charlene Barshefsky, Susan Decker, Reed Hundt, Paul Otellini, James Plummer, David Pottruck, and David Yoffie. The board was described by former Financial Times journalist Tom Foremski as "an exemplary example of corporate governance of the highest order" and received a rating of ten from GovernanceMetrics International, a form of recognition that has only been awarded to twenty-one other corporate boards worldwide.[172]

Employment


Intel microprocessor facility in Costa Rica was responsible in 2006 for 20% of Costa Rican exports and 4.9% of the country's GDP.[173]

The firm promotes very heavily from within, most notably in its executive suite. The company has resisted the trend toward outsider CEOs. Paul Otellini was a 30-year veteran of the company when he assumed the role of CEO. All of his top lieutenants have risen through the ranks after many years with the firm. In many cases, Intel's top executives have spent their entire working careers with Intel.[citation needed]

Intel has a mandatory retirement policy for its CEOs when they reach age 65. Andy Grove retired at 62, while both Robert Noyce and Gordon Moore retired at 58. Grove retired as Chairman and as a member of the board of directors in 2005 at age 68.

Intel's Headquarters are based in Santa Clara, California and has operations around the world. Its largest workforce concentration anywhere is in Washington County, Oregon (in the Portland metropolitan area's "Silicon Forest"), with about 17,000 employees at several facilities and major expansion under way.[174] Outside the United States, the company has facilities in China, Costa Rica, Malaysia, Israel, Ireland, India, Russia and Vietnam, 63 countries and regions internationally. In the U.S. Intel employs significant numbers of people in California, Colorado, Massachusetts, Arizona, New Mexico, Oregon, Texas, Washington and Utah. In Oregon, Intel is the state's largest private employer.[174][175] The company is the largest industrial employer in New Mexico while in Arizona the company has over 10,000 employees.[citation needed]

Intel invests heavily in research in China and about 100 researchers – or 10% of the total number of researchers from Intel – are located in Beijing.[176]

In 2011, the Israeli government offered Intel $290 million to expand in the country. As a condition, Intel will have to employ 1,500 more workers in Kiryat Gat and between 600–1000 workers in the north.[177]

In January 2014, it was reported that Intel would cut about 5,000 jobs from its work force of 107,000. The announcement was made a day after it reported earnings that missed analyst targets.[178]

In March 2014, it was reported that Intel would embark upon a $6 billion plan to expand its activities in Israel. The plan calls for continued investment in existing and new Intel plants until 2030. As of 2014 Intel employs 10,000 workers at four development centers and two production plants in Israel.[179]

Diversity

Intel has a Diversity Initiative, including employee diversity groups as well as supplier diversity programs.[180] Like many companies with employee diversity groups, they include groups based on race and nationality as well as sexual identity and religion. In 1994, Intel sanctioned one of the earliest corporate Gay, Lesbian, Bisexual, and Transgender employee groups,[181] and supports a Muslim employees group,[182] a Jewish employees group,[183] and a Bible-based Christian group.[184][185]

Intel received a 100% rating on the first Corporate Equality Index released by the Human Rights Campaign in 2002. It has maintained this rating in 2003 and 2004. In addition, the company was named one of the 100 Best Companies for Working Mothers in 2005 by Working Mother magazine.[citation needed]

In January 2015, Intel announced the investment of $300 million over the next five years to enhance gender and racial diversity in their own company as well as the technology industry as a whole.[186][187][188][189][190]

Economic Impacts

In 2011, ECONorthwest conducted an economic impact analysis of Intel's economic contribution to the state of Oregon. The report found that in 2009 "the total economic impacts attributed to Intel's operations, capital spending, contributions and taxes amounted to almost $14.6 billion in activity, including $4.3 billion in personal income and 59,990 jobs."[191] Through multiplier effects, every 10 Intel jobs supported, on average, was found to create 31 jobs in other sectors of the economy.[192]

Funding of a school

In Rio Rancho, New Mexico, Intel is the leading employer.[193] In 1997, a community partnership between Sandoval County and Intel Corporation funded and built Rio Rancho High School.[194][195]

Ultrabook Fund

In 2011, Intel Capital announced a new fund to support startups working on technologies in line with the company's concept for next generation notebooks.[196] The company is setting aside a $300 million fund to be spent over the next three to four years in areas related to ultrabooks.[196] Intel announced the ultrabook concept at Computex in 2011. The ultrabook is defined as a thin (less than 0.8 inches [~2 cm] thick[197]) notebook that utilizes Intel processors[197] and also incorporates tablet features such as a touch screen and long battery life.[196][197]

At the Intel Developers Forum in 2011, four Taiwan ODMs showed prototype ultrabooks that used Intel's Ivy Bridge chips.[198] Intel plans to improve power consumption of its chips for ultrabooks, like new Ivy Bridge processors in 2013, which will only have 10W default thermal design power.[199]

Intel's goal for Ultrabook's price is below $1000;[197] however, according to two presidents from Acer and Compaq, this goal will not be achieved if Intel does not lower the price of its chips.[200]

Finances


Intel stock price, Nov 1986 – Nov 2006

Intel's market capitalization is $162.97 billion (February 21, 2015). It publicly trades on NASDAQ with the symbol INTC. A widely held stock, the following indices include Intel shares: Dow Jones Industrial Average, S&P 500, NASDAQ-100, Russell 1000 Index, Russell 1000 Growth Index and SOX (PHLX Semiconductor Sector).

On July 15, 2008, Intel announced that it had achieved the highest earnings in the history of the company during Q2 2008.[201]

Advertising and brand management

Intel Inside

Intel has become one of the world's most recognizable computer brands following its long-running Intel Inside campaign. The campaign, which started in 1991, was created by Intel marketing manager Dennis Carter.[202] The five-note jingle was introduced in 1994 and by its tenth anniversary was being heard in 130 countries around the world. The initial branding agency for the Intel Inside campaign was DahlinSmithWhite Advertising of Salt Lake City. The Intel swirl logo was the work of DahlinSmithWhite art director Steve Grigg under the direction of Intel president and CEO Andy Grove.

The Intel Inside advertising campaign sought public brand loyalty and awareness of Intel processors in consumer computers.[203] Intel paid some of the advertiser's costs for an ad that used the Intel Inside logo and xylomarimba jingle.[204]

The Intel Inside logo from 1991 to 2006.

2009–2011 badge design.

In 2008, Intel planned to shift the emphasis of its Intel Inside campaign from traditional media such as television and print to newer media such as the Internet.[205] Intel required that a minimum of 35% of the money it provided to the companies in its co-op program be used for online marketing.[205] The Intel 2010 annual financial report indicated that $1.8 billion (6% of the gross margin and nearly 16% of the total net income) was allocated to all advertising with Intel Inside being part of that.[206]

The famous D♭  D♭  G♭  D♭  A♭ xylophone/xylomarimba jingle, sonic logo, tag, audio mnemonic was produced by Musikvergnuegen and written by Walter Werzowa, once a member of the Austrian 1980s sampling band Edelweiss.[207] The sonic Intel logo has undergone substantial changes in tone since the introduction of the Pentium III, Pentium 4, and Core processors, yet keeps the same jingle.

Naming strategy

In 2006, Intel expanded its promotion of open specification platforms beyond Centrino, to include the Viiv media center PC and the business desktop Intel vPro.

In mid January 2006, Intel announced that they were dropping the long running Pentium name from their processors. The Pentium name was first used to refer to the P5 core Intel processors (Pent refers to the 5 in P5,) and was done to circumvent court rulings that prevent the trademarking of a string of numbers, so competitors could not just call their processor the same name, as had been done with the prior 386 and 486 processors (both of which had copies manufactured by IBM and AMD). They phased out the Pentium names from mobile processors first, when the new Yonah chips, branded Core Solo and Core Duo, were released. The desktop processors changed when the Core 2 line of processors were released. By 2009 Intel was using a good-better-best strategy with Celeron being good, Pentium better, and the Intel Core family representing the best the company has to offer.[208]

According to spokesman Bill Calder, Intel has maintained only the Celeron brand, the Atom brand for netbooks and the vPro lineup for businesses. Since late 2009, Intel's mainstream processors have been called Celeron, Pentium, Core i3, Core i5, and Core i7, in order of performance from lowest to highest. The first generation core products carry a 3 digit name, such as i5 750, and the second generation products carry a 4 digit name, such as the i5 2500. In both cases, a K at the end of it shows that it is an unlocked processor, enabling additional overclocking abilities (for instance, 2500K). vPro products will carry the Intel Core i7 vPro processor or the Intel Core i5 vPro processor name.[209] In October 2011, Intel started to sell its Core i7-2700K "Sandy Bridge" chip to customers worldwide.[210]

Beginning in 2010, "Centrino" will only be applied to Intel's WiMAX and Wi-Fi technologies; it won't be a PC brand anymore. This will be an evolutionary process taking place over time, Intel acknowledges that multiple brands will be in the market including older ones throughout the transition.[209]

Open source support

Intel has a significant participation in the open source communities since 1999.[211] For example, in 2006 Intel released MIT-licensed X.org drivers for their integrated graphic cards of the i965 family of chipsets. Intel released FreeBSD drivers for some networking cards,[212] available under a BSD-compatible license,[213] which were also ported to OpenBSD.[213] Binary firmware files for non-wireless Ethernet devices were also released under a BSD licence allowing free redistribution.[214] Intel ran the Moblin project until April 23, 2009, when they handed the project over to the Linux Foundation. Intel also runs the LessWatts.org campaigns.[215]

However, after the release of the wireless products called Intel Pro/Wireless 2100, 2200BG/2225BG/2915ABG and 3945ABG in 2005, Intel was criticized for not granting free redistribution rights for the firmware that must be included in the operating system for the wireless devices to operate.[216] As a result of this, Intel became a target of campaigns to allow free operating systems to include binary firmware on terms acceptable to the open source community. Linspire-Linux creator Michael Robertson outlined the difficult position that Intel was in releasing to open source, as Intel did not want to upset their large customer Microsoft.[217] Theo de Raadt of OpenBSD also claimed that Intel is being "an Open Source fraud" after an Intel employee presented a distorted view of the situation at an open-source conference.[218] In spite of the significant negative attention Intel received as a result of the wireless dealings, the binary firmware still has not gained a license compatible with free software principles.[219]

Corporate responsibility record

Intel has been accused by some residents of Rio Rancho, New Mexico of allowing VOCs to be released in excess of their pollution permit. One resident claimed that a release of 1.4 tons of carbon tetrachloride was measured from one acid scrubber during the fourth quarter of 2003 but an emission factor allowed Intel to report no carbon tetrachloride emissions for all of 2003.[220]

Another resident alleges that Intel was responsible for the release of other VOCs from their Rio Rancho site and that a necropsy of lung tissue from two deceased dogs in the area indicated trace amounts of toluene, hexane, ethylbenzene, and xylene isomers,[221] all of which are solvents used in industrial settings but also commonly found in gasoline, retail paint thinners and retail solvents. During a sub-committee meeting of the New Mexico Environment Improvement Board, a resident claimed that Intel's own reports documented more than 1,580 pounds (720 kg) of VOCs were released in June and July 2006.[222]

Intel's environmental performance is published annually in their corporate responsibility report.[223]
In its 2012 rankings on the progress of consumer electronics companies relating to conflict minerals, the Enough Project rated Intel the best of 24 companies, calling it a "Pioneer of progress".[224] In 2014, chief executive Brian Krzanich urged the rest of the industry to follow Intel's lead by also shunning conflict minerals.[225]

Religious controversy

Orthodox Jews have protested against Intel operating in Israel on Saturday, Shabbat. Intel ringed its office with barbed wire before the protest, but there was no violence.[226] As of December 2009, the situation has been stable for Intel Israel while some employees reported working overtime on Shabbat.

Age discrimination

Intel has faced complaints of age discrimination in firing and layoffs. Intel was sued in 1993 by nine former employees, over allegations that they were laid off because they were over the age of 40.[227]

A group called FACE Intel (Former and Current Employees of Intel) claims that Intel weeds out older employees. FACE Intel claims that more than 90 percent of people who have been laid off or fired from Intel are over the age of 40. Upside magazine requested data from Intel breaking out its hiring and firing by age, but the company declined to provide any.[228] Intel has denied that age plays any role in Intel's employment practices.[229] FACE Intel was founded by Ken Hamidi, who was fired from Intel in 1995 at the age of 47.[228] Hamidi was blocked in a 1999 court decision from using Intel's email system to distribute criticism of the company to employees,[230] which overturned in 2003 in Intel Corp. v. Hamidi.

Competition

In the 1980s, Intel was among the top ten sellers of semiconductors (10th in 1987) in the world. In 1991, Intel became the biggest chip maker by revenue and has held the position ever since. Other top semiconductor companies include TSMC, Advanced Micro Devices, Samsung, Texas Instruments, Toshiba and STMicroelectronics.

Competitors in PC chip sets include AMD, VIA Technologies, SiS, and Nvidia. Intel's competitors in networking include Freescale, Infineon, Broadcom, Marvell Technology Group and AMCC, and competitors in flash memory include Spansion, Samsung, Qimonda, Toshiba, STMicroelectronics, and Hynix.

The only major competitor in the x86 processor market is Advanced Micro Devices (AMD), with which Intel has had full cross-licensing agreements since 1976: each partner can use the other's patented technological innovations without charge after a certain time.[231] However, the cross-licensing agreement is canceled in the event of an AMD bankruptcy or takeover.[232] Some smaller competitors such as VIA and Transmeta produce low-power x86 processors for small factor computers and portable equipment. However, the advent of such mobile computing devices, in particular, smartphones, has in recent years led to a decline in PC sales. This is seen as the main reason for Intel's 2013 Q1 net income drop of 25%.[233] As over 95% of the world's smartphones are currently powered by processors designed by ARM Holdings, this company has become a major competitor for Intel's processor market. ARM is also planning to make inroads into the PC and server market.[234]

Lawsuits

Intel has often been accused by competitors of using legal claims to thwart competition. Intel claims that it is defending its intellectual property. Intel has been plaintiff and defendant in numerous legal actions.

In September 2005, Intel filed a response to an AMD lawsuit,[235] disputing AMD's claims, and claiming that Intel's business practices are fair and lawful. In a rebuttal, Intel deconstructed AMD's offensive strategy and argued that AMD struggled largely as a result of its own bad business decisions, including underinvestment in essential manufacturing capacity and excessive reliance on contracting out chip foundries.[236] Legal analysts predicted the lawsuit would drag on for a number of years, since Intel's initial response indicated its unwillingness to settle with AMD.[237][238] In 2008 a court date was finally set,[239] but in 2009 Intel settled with a $1.25 billion payout to AMD (see below).[240]

In October 2006, a Transmeta lawsuit was filed against Intel for patent infringement on computer architecture and power efficiency technologies.[241] The lawsuit was settled in October 2007, with Intel agreeing to pay US$150 million initially and US$20 million per year for the next five years. Both companies agreed to drop lawsuits against each other, while Intel was granted a perpetual non-exclusive license to use current and future patented Transmeta technologies in its chips for 10 years.[242]

On November 4, 2009, New York's attorney general filed an antitrust lawsuit against Intel Corp, claiming the company used "illegal threats and collusion" to dominate the market for computer microprocessors.

On November 12, 2009, AMD agreed to drop the antitrust lawsuit against Intel in exchange for $1.25 billion.[240] A joint press release published by the two chip makers stated "While the relationship between the two companies has been difficult in the past, this agreement ends the legal disputes and enables the companies to focus all of our efforts on product innovation and development."[243][244]

An antitrust lawsuit[245] and a class-action suit relating to cold calling employees of other companies is still pending. [246]

Anti-competitive allegations

Japan

In 2005, the local Fair Trade Commission found that Intel violated the Japanese Antimonopoly Act. The commission ordered Intel to eliminate discounts that had discriminated against AMD. To avoid a trial, Intel agreed to comply with the order.[247][248][249][250]

European Union

In July 2007, the European Commission accused Intel of anti-competitive practices, mostly against AMD.[251] The allegations, going back to 2003, include giving preferential prices to computer makers buying most or all of their chips from Intel, paying computer makers to delay or cancel the launch of products using AMD chips, and providing chips at below standard cost to governments and educational institutions.[252] Intel responded that the allegations were unfounded and instead qualified its market behavior as consumer-friendly.[252] General counsel Bruce Sewell responded that the Commission had misunderstood some factual assumptions as to pricing and manufacturing costs.[253]

In February 2008, Intel stated that its office in Munich had been raided by European Union regulators. Intel reported that it was cooperating with investigators.[254] Intel faced a fine of up to 10% of its annual revenue, if found guilty of stifling competition.[255] AMD subsequently launched a website promoting these allegations.[256][257] In June 2008, the EU filed new charges against Intel.[258] In May 2009, the EU found that Intel had engaged in anti-competitive practices and subsequently fined Intel €1.06 billion (US$1.44 billion), a record amount. Intel was found to have paid companies, including Acer, Dell, HP, Lenovo and NEC,[259] to exclusively use Intel chips in their products, and therefore harmed other companies including AMD.[259][260][261] The European Commission said that Intel had deliberately acted to keep competitors out of the computer chip market and in doing so had made a "serious and sustained violation of the EU's antitrust rules".[259] In addition to the fine, Intel was ordered by the Commission to immediately cease all illegal practices.[259] Intel has stated that they will appeal against the Commission's verdict. In June 2014, the General Court, which sits below the European Court of Justice, rejected the appeal.[259]

South Korea

In September 2007, South Korean regulators accused Intel of breaking antitrust law. The investigation began in February 2006, when officials raided Intel's South Korean offices. The company risked a penalty of up to 3% of its annual sales, if found guilty.[262] In June 2008, the Fair Trade Commission ordered Intel to pay a fine of US$25.5 million for taking advantage of its dominant position to offer incentives to major Korean PC manufacturers on the condition of not buying products from AMD.[263]

United States

New York started an investigation of Intel in January 2008 on whether the company violated antitrust laws in pricing and sales of its microprocessors.[264] In June 2008, the Federal Trade Commission also began an antitrust investigation of the case.[265] In December 2009, the FTC announced it would initiate an administrative proceeding against Intel in September 2010.[266][267][268][269]

In November 2009, following a two-year investigation, New York Attorney General Andrew Cuomo sued Intel, accusing them of bribery and coercion, claiming that Intel bribed computer makers to buy more of their chips than those of their rivals, and threatened to withdraw these payments if the computer makers were perceived as working too closely with its competitors. Intel has denied these claims.[270]

On July 22, 2010, Dell agreed to a settlement with the U.S. Securities and Exchange Commission (SEC) to pay $100M in penalties resulting from charges that Dell did not accurately disclose accounting information to investors. In particular, the SEC charged that from 2002 to 2006, Dell had an agreement with Intel to receive rebates in exchange for not using chips manufactured by AMD. These substantial rebates were not disclosed to investors, but were used to help meet investor expectations regarding the company's financial performance; "These exclusivity payments grew from 10 percent of Dell's operating income in FY 2003 to 38 percent in FY 2006, and peaked at 76 percent in the first quarter of FY 2007.".[271] Dell eventually did adopt AMD as a secondary supplier in 2006, and Intel subsequently stopped their rebates, causing Dell's financial performance to fall.[272][273][274]

Market share

According to IDC, while Intel still enjoys the biggest market share in both the overall worldwide PC microprocessor market (79.3%) and the mobile PC microprocessor (84.4%) in the second quarter of 2011, the numbers decreased by 1.5% and 1.9% compared to the first quarter.[275][276]

Per Passmark's (?) CPU benchmark, which takes into account individual benchmarking of their software and each system results are reported with, Intel has retained 70% and more of the active market versus AMD since Q1 2008.[277]

Boycott, Divestment and Sanctions

According to the Christian Science Monitor, Intel's plant at Kiryat Gat was built on the site of former Palestinian villages of Al-Faluja and Iraq al-Manshiyya; and Al-Awda - the Palestinian Right to Return Coalition - a supporter of Boycott, Divestment and Sanctions, has called on Intel to close this plant.[278]

Friday, February 27, 2015

Nuclear meltdown



From Wikipedia, the free encyclopedia


Three of the reactors at Fukushima I overheated, causing core meltdowns. This was compounded by hydrogen gas explosions and the venting of contaminated steam which released large amounts of radioactive material into the air.[1]

Three Mile Island Nuclear Generating Station consisted of two pressurized water reactors manufactured by Babcock & Wilcox, each inside its own containment building and connected cooling towers. Unit 2, which suffered a partial core melt, is in the background.

A nuclear meltdown is an informal term for a severe nuclear reactor accident that results in core damage from overheating. The term is not officially defined by the International Atomic Energy Agency[2] or by the Nuclear Regulatory Commission.[3] However, it has been defined to mean the accidental melting of the core of a nuclear reactor,[4] and is in common usage a reference to the core's either complete or partial collapse. "Core melt accident" and "partial core melt"[5] are the analogous technical terms for a meltdown.

A core melt accident occurs when the heat generated by a nuclear reactor exceeds the heat removed by the cooling systems to the point where at least one nuclear fuel element exceeds its melting point. This differs from a fuel element failure, which is not caused by high temperatures. A meltdown may be caused by a loss of coolant, loss of coolant pressure, or low coolant flow rate or be the result of a criticality excursion in which the reactor is operated at a power level that exceeds its design limits. Alternately, in a reactor plant such as the RBMK-1000, an external fire may endanger the core, leading to a meltdown.

Once the fuel elements of a reactor begin to melt, the fuel cladding has been breached, and the nuclear fuel (such as uranium, plutonium, or thorium) and fission products (such as cesium-137, krypton-85, or iodine-131) within the fuel elements can leach out into the coolant. Subsequent failures can permit these radioisotopes to breach further layers of containment. Superheated steam and hot metal inside the core can lead to fuel-coolant interactions, hydrogen explosions, or water hammer, any of which could destroy parts of the containment. A meltdown is considered very serious because of the potential for radioactive materials to breach all containment and escape (or be released) into the environment, resulting in radioactive contamination and fallout, and potentially leading to radiation poisoning of people and animals nearby.

Causes

Nuclear power plants generate electricity by heating fluid via a nuclear reaction to run a generator. If the heat from that reaction is not removed adequately, the fuel assemblies in a reactor core can melt. A core damage incident can occur even after a reactor is shut down because the fuel continues to produce decay heat.

A core damage accident is caused by the loss of sufficient cooling for the nuclear fuel within the reactor core. The reason may be one of several factors, including a loss-of-pressure-control accident, a loss-of-coolant accident (LOCA), an uncontrolled power excursion or, in reactors without a pressure vessel, a fire within the reactor core. Failures in control systems may cause a series of events resulting in loss of cooling. Contemporary safety principles of defense in depth ensure that multiple layers of safety systems are always present to make such accidents unlikely.

The containment building is the last of several safeguards that prevent the release of radioactivity to the environment. Many commercial reactors are contained within a 1.2-to-2.4-metre (3.9 to 7.9 ft) thick pre-stressed, steel-reinforced, air-tight concrete structure that can withstand hurricane-force winds and severe earthquakes.
  • In a loss-of-coolant accident, either the physical loss of coolant (which is typically deionized water, an inert gas, NaK, or liquid sodium) or the loss of a method to ensure a sufficient flow rate of the coolant occurs. A loss-of-coolant accident and a loss-of-pressure-control accident are closely related in some reactors. In a pressurized water reactor, a LOCA can also cause a "steam bubble" to form in the core due to excessive heating of stalled coolant or by the subsequent loss-of-pressure-control accident caused by a rapid loss of coolant. In a loss-of-forced-circulation accident, a gas cooled reactor's circulators (generally motor or steam driven turbines) fail to circulate the gas coolant within the core, and heat transfer is impeded by this loss of forced circulation, though natural circulation through convection will keep the fuel cool as long as the reactor is not depressurized.[6]
  • In a loss-of-pressure-control accident, the pressure of the confined coolant falls below specification without the means to restore it. In some cases this may reduce the heat transfer efficiency (when using an inert gas as a coolant) and in others may form an insulating "bubble" of steam surrounding the fuel assemblies (for pressurized water reactors). In the latter case, due to localized heating of the "steam bubble" due to decay heat, the pressure required to collapse the "steam bubble" may exceed reactor design specifications until the reactor has had time to cool down. (This event is less likely to occur in boiling water reactors, where the core may be deliberately depressurized so that the Emergency Core Cooling System may be turned on). In a depressurization fault, a gas-cooled reactor loses gas pressure within the core, reducing heat transfer efficiency and posing a challenge to the cooling of fuel; however, as long as at least one gas circulator is available, the fuel will be kept cool.[6]
  • In an uncontrolled power excursion accident, a sudden power spike in the reactor exceeds reactor design specifications due to a sudden increase in reactor reactivity. An uncontrolled power excursion occurs due to significantly altering a parameter that affects the neutron multiplication rate of a chain reaction (examples include ejecting a control rod or significantly altering the nuclear characteristics of the moderator, such as by rapid cooling). In extreme cases the reactor may proceed to a condition known as prompt critical. This is especially a problem in reactors that have a positive void coefficient of reactivity, a positive temperature coefficient, are overmoderated, or can trap excess quantities of deleterious fission products within their fuel or moderators. Many of these characteristics are present in the RBMK design, and the Chernobyl disaster was caused by such deficiencies as well as by severe operator negligence. Western light water reactors are not subject to very large uncontrolled power excursions because loss of coolant decreases, rather than increases, core reactivity (a negative void coefficient of reactivity); "transients," as the minor power fluctuations within Western light water reactors are called, are limited to momentary increases in reactivity that will rapidly decrease with time (approximately 200% - 250% of maximum neutronic power for a few seconds in the event of a complete rapid shutdown failure combined with a transient).
  • Core-based fires endanger the core and can cause the fuel assemblies to melt. A fire may be caused by air entering a graphite moderated reactor, or a liquid-sodium cooled reactor. Graphite is also subject to accumulation of Wigner energy, which can overheat the graphite (as happened at the Windscale fire). Light water reactors do not have flammable cores or moderators and are not subject to core fires. Gas-cooled civilian reactors, such as the Magnox, UNGG, and AGCR type reactors, keep their cores blanketed with non reactive carbon dioxide gas, which cannot support a fire. Modern gas-cooled civilian reactors use helium, which cannot burn, and have fuel that can withstand high temperatures without melting (such as the High Temperature Gas Cooled Reactor and the Pebble Bed Modular Reactor).
  • Byzantine faults and cascading failures within instrumentation and control systems may cause severe problems in reactor operation, potentially leading to core damage if not mitigated. For example, the Browns Ferry fire damaged control cables and required the plant operators to manually activate cooling systems. The Three Mile Island accident was caused by a stuck-open pilot-operated pressure relief valve combined with a deceptive water level gauge that misled reactor operators, which resulted in core damage.

Light water reactors (LWRs)


TMI-2 Core End-State Configuration
Before the core of a light water nuclear reactor can be damaged, two precursor events must have already occurred:
  • A limiting fault (or a set of compounded emergency conditions) that leads to the failure of heat removal within the core (the loss of cooling). Low water level uncovers the core, allowing it to heat up.
  • Failure of the Emergency Core Cooling System (ECCS). The ECCS is designed to rapidly cool the core and make it safe in the event of the maximum fault (the design basis accident) that nuclear regulators and plant engineers could imagine. There are at least two copies of the ECCS built for every reactor. Each division (copy) of the ECCS is capable, by itself, of responding to the design basis accident. The latest reactors have as many as four divisions of the ECCS. This is the principle of redundancy, or duplication. As long as at least one ECCS division functions, no core damage can occur. Each of the several divisions of the ECCS has several internal "trains" of components. Thus the ECCS divisions themselves have internal redundancy – and can withstand failures of components within them.
The Three Mile Island accident was a compounded group of emergencies that led to core damage.
What led to this was an erroneous decision by operators to shut down the ECCS during an emergency condition due to gauge readings that were either incorrect or misinterpreted; this caused another emergency condition that, several hours after the fact, led to core exposure and a core damage incident. If the ECCS had been allowed to function, it would have prevented both exposure and core damage. During the Fukushima incident the emergency cooling system had also been manually shut down several minutes after it started.[7]

If such a limiting fault were to occur, and a complete failure of all ECCS divisions were to occur, both Kuan, et al and Haskin, et al describe six stages between the start of the limiting fault (the loss of cooling) and the potential escape of molten corium into the containment (a so-called "full meltdown"):[8][9]
  1. Uncovering of the Core – In the event of a transient, upset, emergency, or limiting fault, LWRs are designed to automatically SCRAM (a SCRAM being the immediate and full insertion of all control rods) and spin up the ECCS. This greatly reduces reactor thermal power (but does not remove it completely); this delays core becoming uncovered, which is defined as the point when the fuel rods are no longer covered by coolant and can begin to heat up. As Kuan states: "In a small-break LOCA with no emergency core coolant injection, core uncovery [sic] generally begins approximately an hour after the initiation of the break. If the reactor coolant pumps are not running, the upper part of the core will be exposed to a steam environment and heatup of the core will begin. However, if the coolant pumps are running, the core will be cooled by a two-phase mixture of steam and water, and heatup of the fuel rods will be delayed until almost all of the water in the two-phase mixture is vaporized. The TMI-2 accident showed that operation of reactor coolant pumps may be sustained for up to approximately two hours to deliver a two phase mixture that can prevent core heatup."[8]
  2. Pre-damage heat up – "In the absence of a two-phase mixture going through the core or of water addition to the core to compensate water boiloff, the fuel rods in a steam environment will heat up at a rate between 0.3 °C/s (0.5 °F/s) and 1 °C/s (1.8 °F/s) (3)."[8]
  3. Fuel ballooning and bursting – "In less than half an hour, the peak core temperature would reach 1,100 K (830 °C). At this temperature the zircaloy cladding of the fuel rods may balloon and burst. This is the first stage of core damage. Cladding ballooning may block a substantial portion of the flow area of the core and restrict the flow of coolant. However, complete blockage of the core is unlikely because not all fuel rods balloon at the same axial location. In this case, sufficient water addition can cool the core and stop core damage progression."[8]
  4. Rapid oxidation – "The next stage of core damage, beginning at approximately 1,500 K (1,230 °C), is the rapid oxidation of the Zircaloy by steam. In the oxidation process, hydrogen is produced and a large amount of heat is released. Above 1,500 K (1,230 °C), the power from oxidation exceeds that from decay heat (4,5) unless the oxidation rate is limited by the supply of either zircaloy or steam."[8]
  5. Debris bed formation – "When the temperature in the core reaches about 1,700 K (1,430 °C), molten control materials (1,6) will flow to and solidify in the space between the lower parts of the fuel rods where the temperature is comparatively low. Above 1,700 K (1,430 °C), the core temperature may escalate in a few minutes to the melting point of zircaloy [2,150 K (1,880 °C)] due to increased oxidation rate. When the oxidized cladding breaks, the molten zircaloy, along with dissolved UO2 (1,7) would flow downward and freeze in the cooler, lower region of the core. Together with solidified control materials from earlier down-flows, the relocated zircaloy and UO2 would form the lower crust of a developing cohesive debris bed."[8]
  6. (Corium) Relocation to the lower plenum – "In scenarios of small-break LOCAs, there is generally a pool of water in the lower plenum of the vessel at the time of core relocation. Release of molten core materials into water always generates large amounts of steam. If the molten stream of core materials breaks up rapidly in water, there is also a possibility of a steam explosion. During relocation, any unoxidized zirconium in the molten material may also be oxidized by steam, and in the process hydrogen is produced. Recriticality also may be a concern if the control materials are left behind in the core and the relocated material breaks up in unborated water in the lower plenum."[8]
At the point at which the corium relocates to the lower plenum, Haskin, et al relate that the possibility exists for an incident called a fuel-coolant interaction (FCI) to substantially stress or breach the primary pressure boundary when the corium relocates to the lower plenum of the reactor pressure vessel ("RPV").[10] This is because the lower plenum of the RPV may have a substantial quantity of water - the reactor coolant - in it, and, assuming the primary system has not been depressurized, the water will likely be in the liquid phase, and consequently dense, and at a vastly lower temperature than the corium. Since corium is a liquid metal-ceramic eutectic at temperatures of 2,200 to 3,200 K (1,930 to 2,930 °C), its fall into liquid water at 550 to 600 K (277 to 327 °C) may cause an extremely rapid evolution of steam that could cause a sudden extreme overpressure and consequent gross structural failure of the primary system or RPV.[10] Though most modern studies hold that it is physically infeasible, or at least extraordinarily unlikely, Haskin, et al state that there exists a remote possibility of an extremely violent FCI leading to something referred to as an alpha-mode failure, or the gross failure of the RPV itself, and subsequent ejection of the upper plenum of the RPV as a missile against the inside of the containment, which would likely lead to the failure of the containment and release of the fission products of the core to the outside environment without any substantial decay having taken place.[11]

The American Nuclear Society has said "despite melting of about one-third of the fuel, the reactor vessel itself maintained its integrity and contained the damaged fuel."[12]

Breach of the Primary Pressure Boundary

There are several possibilities as to how the primary pressure boundary could be breached by corium.
  • Steam Explosion
As previously described, FCI could lead to an overpressure event leading to RPV fail, and thus, primary pressure boundary fail. Haskin, et al. report that in the event of a steam explosion, failure of the lower plenum is far more likely than ejection of the upper plenum in the alpha-mode. In the event of lower plenum failure, debris at varied temperatures can be expected to be projected into the cavity below the core. The containment may be subject to overpressure, though this is not likely to fail the containment. The alpha-mode failure will lead to the consequences previously discussed.
  • Pressurized Melt Ejection (PME)
It is quite possible, especially in pressurized water reactors, that the primary loop will remain pressurized following corium relocation to the lower plenum. As such, pressure stresses on the RPV will be present in addition to the weight stress that the molten corium places on the lower plenum of the RPV; when the metal of the RPV weakens sufficiently due to the heat of the molten corium, it is likely that the liquid corium will be discharged under pressure out of the bottom of the RPV in a pressurized stream, together with entrained gases. This mode of corium ejection may lead to direct containment heating (DCH).

Severe Accident Ex-Vessel Interactions and Challenges to Containment

Haskin, et al identify six modes by which the containment could be credibly challenged; some of these modes are not applicable to core melt accidents.
  1. Overpressure
  2. Dynamic pressure (shockwaves)
  3. Internal missiles
  4. External missiles (not applicable to core melt accidents)
  5. Meltthrough
  6. Bypass

Standard failure modes

If the melted core penetrates the pressure vessel, there are theories and speculations as to what may then occur.

In modern Russian plants, there is a "core catching device" in the bottom of the containment building. The melted core is supposed to hit a thick layer of a "sacrificial metal" which would melt, dilute the core and increase the heat conductivity, and finally the diluted core can be cooled down by water circulating in the floor. However, there has never been any full-scale testing of this device.[13]

In Western plants there is an airtight containment building. Though radiation would be at a high level within the containment, doses outside of it would be lower. Containment buildings are designed for the orderly release of pressure without releasing radionuclides, through a pressure release valve and filters. Hydrogen/oxygen recombiners also are installed within the containment to prevent gas explosions.

In a melting event, one spot or area on the RPV will become hotter than other areas, and will eventually melt. When it melts, corium will pour into the cavity under the reactor. Though the cavity is designed to remain dry, several NUREG-class documents advise operators to flood the cavity in the event of a fuel melt incident. This water will become steam and pressurize the containment.
Automatic water sprays will pump large quantities of water into the steamy environment to keep the pressure down. Catalytic recombiners will rapidly convert the hydrogen and oxygen back into water. One positive effect of the corium falling into water is that it is cooled and returns to a solid state.

Extensive water spray systems within the containment along with the ECCS, when it is reactivated, will allow operators to spray water within the containment to cool the core on the floor and reduce it to a low temperature.

These procedures are intended to prevent release of radiation. In the Three Mile Island event in 1979, a theoretical person standing at the plant property line during the entire event would have received a dose of approximately 2 millisieverts (200 millirem), between a chest X-ray's and a CT scan's worth of radiation. This was due to outgassing by an uncontrolled system that, today, would have been backfitted with activated carbon and HEPA filters to prevent radionuclide release.

However in case of Fukushima incident this design also at least partially failed: large amounts of highly radioactive water were produced and nuclear fuel has possibly melted through the base of the pressure vessels.[14][citation needed]

Cooling will take quite a while, until the natural decay heat of the corium reduces to the point where natural convection and conduction of heat to the containment walls and re-radiation of heat from the containment allows for water spray systems to be shut down and the reactor put into safe storage. The containment can be sealed with release of extremely limited offsite radioactivity and release of pressure within the containment. After a number of years for fission products to decay - probably around a decade - the containment can be reopened for decontamination and demolition.

Unexpected failure modes

Another scenario sees a buildup of hydrogen, which may lead to a detonation event, as happened for three reactors during Fukushima incident. Catalytic hydrogen recombiners located within containment are designed to prevent this from occurring; however, in Fukushima recombiners did not work due the absence of power and hydrogen detonation breached the containment. During the 1979 Three Mile Island accident a hydrogen bubble formed in the pressure vessel dome. There were initial concerns that this hydrogen bubble might ignite and damage the pressure vessel or even damage the containment building; but it was soon realized that a lack of oxygen precluded a burnable or explosive mixture from forming inside the pressure vessel.[15]

Speculative failure modes

One scenario consists of the reactor pressure vessel failing all at once, with the entire mass of corium dropping into a pool of water (for example, coolant or moderator) and causing extremely rapid generation of steam. The pressure rise within the containment could threaten integrity if rupture disks could not relieve the stress. Exposed flammable substances could burn, but there are few, if any, flammable substances within the containment.

Another theory called an 'alpha mode' failure by the 1975 Rasmussen (WASH-1400) study asserted steam could produce enough pressure to blow the head off the reactor pressure vessel (RPV). The containment could be threatened if the RPV head collided with it. (The WASH-1400 report was replaced by better-based[original research?] newer studies, and now the Nuclear Regulatory Commission has disavowed them all and is preparing the overarching State-of-the-Art Reactor Consequence Analyses [SOARCA] study - see the Disclaimer in NUREG-1150.)

It has not been determined to what extent a molten mass can melt through a structure (although that was tested in the Loss-of-Fluid-Test Reactor described in Test Area North's fact sheet[16]). The Three Mile Island accident provided some real-life experience, with an actual molten core within an actual structure; the molten corium failed to melt through the Reactor Pressure Vessel after over six hours of exposure, due to dilution of the melt by the control rods and other reactor internals, validating the emphasis on defense in depth against core damage incidents. Some believe a molten reactor core could actually penetrate the reactor pressure vessel and containment structure and burn downwards into the earth beneath, to the level of the groundwater.

By 1970, there were doubts about the ability of the emergency cooling systems of a nuclear reactor to prevent a loss of coolant accident and the consequent meltdown of the fuel core; the subject proved popular in the technical and the popular presses.[17] In 1971, in the article Thoughts on Nuclear Plumbing, former Manhattan Project nuclear physicist Ralph Lapp used the term "China syndrome" to describe a possible burn-through of the containment structures, and the subsequent escape of radioactive material(s) into the atmosphere and environment. The hypothesis derived from a 1967 report by a group of nuclear physicists, headed by W. K. Ergen.[18]

Other reactor types

Other types of reactors have different capabilities and safety profiles than the LWR does. Advanced varieties of several of these reactors have the potential to be inherently safe.

CANDU reactors

CANDU reactors, Canadian-invented deuterium-uranium design, are designed with at least one, and generally two, large low-temperature and low-pressure water reservoirs around their fuel/coolant channels. The first is the bulk heavy-water moderator (a separate system from the coolant), and the second is the light-water-filled shield tank. These backup heat sinks are sufficient to prevent either the fuel meltdown in the first place (using the moderator heat sink), or the breaching of the core vessel should the moderator eventually boil off (using the shield tank heat sink).[19] Other failure modes aside from fuel melt will probably occur in a CANDU rather than a meltdown, such as deformation of the calandria into a non-critical configuration. All CANDU reactors are located within standard Western containments as well.

Gas-cooled reactors

One type of Western reactor, known as the advanced gas-cooled reactor (or AGCR), built by the United Kingdom, is not very vulnerable to loss-of-cooling accidents or to core damage except in the most extreme of circumstances. By virtue of the relatively inert coolant (carbon dioxide), the large volume and high pressure of the coolant, and the relatively high heat transfer efficiency of the reactor, the time frame for core damage in the event of a limiting fault is measured in days. Restoration of some means of coolant flow will prevent core damage from occurring.

Other types of highly advanced gas cooled reactors, generally known as high-temperature gas-cooled reactors (HTGRs) such as the Japanese High Temperature Test Reactor and the United States' Very High Temperature Reactor, are inherently safe, meaning that meltdown or other forms of core damage are physically impossible, due to the structure of the core, which consists of hexagonal prismatic blocks of silicon carbide reinforced graphite infused with TRISO or QUADRISO pellets of uranium, thorium, or mixed oxide buried underground in a helium-filled steel pressure vessel within a concrete containment. Though this type of reactor is not susceptible to meltdown, additional capabilities of heat removal are provided by using regular atmospheric airflow as a means of backup heat removal, by having it pass through a heat exchanger and rising into the atmosphere due to convection, achieving full residual heat removal. The VHTR is scheduled to be prototyped and tested at Idaho National Laboratory within the next decade (as of 2009) as the design selected for the Next Generation Nuclear Plant by the US Department of Energy. This reactor will use a gas as a coolant, which can then be used for process heat (such as in hydrogen production) or for the driving of gas turbines and the generation of electricity.

A similar highly advanced gas cooled reactor originally designed by West Germany (the AVR reactor) and now developed by South Africa is known as the Pebble Bed Modular Reactor. It is an inherently safe design, meaning that core damage is physically impossible, due to the design of the fuel (spherical graphite "pebbles" arranged in a bed within a metal RPV and filled with TRISO (or QUADRISO) pellets of uranium, thorium, or mixed oxide within). A prototype of a very similar type of reactor has been built by the Chinese, HTR-10, and has worked beyond researchers' expectations, leading the Chinese to announce plans to build a pair of follow-on, full-scale 250 MWe, inherently safe, power production reactors based on the same concept. (See Nuclear power in the People's Republic of China for more information.)

Lead and Lead-Bismuth-cooled reactors

Recently it was identified a special phenomenology for heavy liquid metal-cooled fast reactors -HLM, as lead and lead-bismuth-cooled reactors.[20] Because of the similar densities of the fuel and the HLM, an inherent passive safety self-removal feedback mechanism due to buoyancy forces is developed, which propels the packed bed away from the wall when certain threshold of temperature is attained and the bed becomes lighter than the surrounding coolant, thus preventing temperatures that can jeopardize the vessel’s structural integrity and also reducing the recriticality potential by limiting the allowable bed depth.

Experimental or conceptual designs

Some design concepts for nuclear reactors emphasize resistance to meltdown and operating safety.
The PIUS (process inherent ultimate safety) designs, originally engineered by the Swedes in the late 1970s and early 1980s, are LWRs that by virtue of their design are resistant to core damage. No units have ever been built.

Power reactors, including the Deployable Electrical Energy Reactor, a larger-scale mobile version of the TRIGA for power generation in disaster areas and on military missions, and the TRIGA Power System, a small power plant and heat source for small and remote community use, have been put forward by interested engineers, and share the safety characteristics of the TRIGA due to the uranium zirconium hydride fuel used.

The Hydrogen Moderated Self-regulating Nuclear Power Module, a reactor that uses uranium hydride as a moderator and fuel, similar in chemistry and safety to the TRIGA, also possesses these extreme safety and stability characteristics, and has attracted a good deal of interest in recent times.

The liquid fluoride thorium reactor is designed to naturally have its core in a molten state, as a eutectic mix of thorium and fluorine salts. As such, a molten core is reflective of the normal and safe state of operation of this reactor type. In the event the core overheats, a metal plug will melt, and the molten salt core will drain into tanks where it will cool in a non-critical configuration. Since the core is liquid, and already melted, it cannot be damaged.

Advanced liquid metal reactors, such as the U.S. Integral Fast Reactor and the Russian BN-350, BN-600, and BN-800, all have a coolant with very high heat capacity, sodium metal. As such, they can withstand a loss of cooling without SCRAM and a loss of heat sink without SCRAM, qualifying them as inherently safe.

Soviet Union-designed reactors

RBMKs

Soviet-designed RBMKs, found only in Russia and the CIS and now shut down everywhere except Russia, do not have containment buildings, are naturally unstable (tending to dangerous power fluctuations), and also have ECCS systems that are considered grossly inadequate by Western safety standards. The reactor from the Chernobyl Disaster was a RBMK reactor.

RBMK ECCS systems only have one division and have less than sufficient redundancy within that division. Though the large core size of the RBMK makes it less energy-dense than the Western LWR core, it makes it harder to cool. The RBMK is moderated by graphite. In the presence of both steam and oxygen, at high temperatures, graphite forms synthesis gas and with the water gas shift reaction the resultant hydrogen burns explosively. If oxygen contacts hot graphite, it will burn. The RBMK tends towards dangerous power fluctuations. Control rods used to be tipped with graphite, a material that slows neutrons and thus speeds up the chain reaction. Water is used as a coolant, but not a moderator. If the water boils away, cooling is lost, but moderation continues. This is termed a positive void coefficient of reactivity.

Control rods can become stuck if the reactor suddenly heats up and they are moving. Xenon-135, a neutron absorbent fission product, has a tendency to build up in the core and burn off unpredictably in the event of low power operation. This can lead to inaccurate neutronic and thermal power ratings.

The RBMK does not have any containment above the core. The only substantial solid barrier above the fuel is the upper part of the core, called the upper biological shield, which is a piece of concrete interpenetrated with control rods and with access holes for refueling while online. Other parts of the RBMK were shielded better than the core itself. Rapid shutdown (SCRAM) takes 10 to 15 seconds. Western reactors take 1 - 2.5 seconds.

Western aid has been given to provide certain real-time safety monitoring capacities to the human staff. Whether this extends to automatic initiation of emergency cooling is not known. Training has been provided in safety assessment from Western sources, and Russian reactors have evolved in result to the weaknesses that were in the RBMK. However, numerous RBMKs still operate.

It is safe to say that it might be possible to stop a loss-of-coolant event prior to core damage occurring, but that any core damage incidents will probably assure massive release of radioactive materials. Further, dangerous power fluctuations are natural to the design.

Lithuania joined the EU recently, and upon acceding, it has been required to shut the two RBMKs that it has at Ignalina NPP, as such reactors are totally incompatible with the nuclear safety standards of Europe. It will be replacing them with some safer form of reactor.

MKER

The MKER is a modern Russian-engineered channel type reactor that is a distant descendant of the RBMK. It approaches the concept from a different and superior direction, optimizing the benefits, and fixing the flaws of the original RBMK design.

There are several unique features of the MKER's design that make it a credible and interesting option: One unique benefit of the MKER's design is that in the event of a challenge to cooling within the core - a pipe break of a channel, the channel can be isolated from the plenums supplying water, decreasing the potential for common-mode failures.

The lower power density of the core greatly enhances thermal regulation. Graphite moderation enhances neutronic characteristics beyond light water ranges. The passive emergency cooling system provides a high level of protection by using natural phenomena to cool the core rather than depending on motor-driven pumps. The containment structure is modern and designed to withstand a very high level of punishment.

Refueling is accomplished while online, ensuring that outages are for maintenance only and are very few and far between. 97-99% uptime is a definite possibility. Lower enrichment fuels can be used, and high burnup can be achieved due to the moderator design. Neutronics characteristics have been revamped to optimize for purely civilian fuel fertilization and recycling.

Due to the enhanced quality control of parts, advanced computer controls, comprehensive passive emergency core cooling system, and very strong containment structure, along with a negative void coefficient and a fast acting rapid shutdown system, the MKER's safety can generally be regarded as being in the range of the Western Generation III reactors, and the unique benefits of the design may enhance its competitiveness in countries considering full fuel-cycle options for nuclear development.

VVER

The VVER is a pressurized light water reactor that is far more stable and safe than the RBMK. This is because it uses light water as a moderator (rather than graphite), has well understood operating characteristics, and has a negative void coefficient of reactivity. In addition, some have been built with more than marginal containments, some have quality ECCS systems, and some have been upgraded to international standards of control and instrumentation. Present generations of VVERs (the VVER-1000) are built to Western-equivalent levels of instrumentation, control, and containment systems.

However, even with these positive developments, certain older VVER models raise a high level of concern, especially the VVER-440 V230.[21]

The VVER-440 V230 has no containment building, but only has a structure capable of confining steam surrounding the RPV. This is a volume of thin steel, perhaps an inch or two in thickness, grossly insufficient by Western standards.
  • Has no ECCS. Can survive at most one 4 inch pipe break (there are many pipes greater than 4 inches within the design).
  • Has six steam generator loops, adding unnecessary complexity.
    • However, apparently steam generator loops can be isolated, in the event that a break occurs in one of these loops. The plant can remain operating with one isolated loop - a feature found in few Western reactors.
The interior of the pressure vessel is plain alloy steel, exposed to water. This can lead to rust, if the reactor is exposed to water. One point of distinction in which the VVER surpasses the West is the reactor water cleanup facility - built, no doubt, to deal with the enormous volume of rust within the primary coolant loop - the product of the slow corrosion of the RPV. This model is viewed as having inadequate process control systems.

Bulgaria had a number of VVER-440 V230 models, but they opted to shut them down upon joining the EU rather than backfit them, and are instead building new VVER-1000 models. Many non-EU states maintain V230 models, including Russia and the CIS. Many of these states - rather than abandoning the reactors entirely - have opted to install an ECCS, develop standard procedures, and install proper instrumentation and control systems. Though confinements cannot be transformed into containments, the risk of a limiting fault resulting in core damage can be greatly reduced.

The VVER-440 V213 model was built to the first set of Soviet nuclear safety standards. It possesses a modest containment building, and the ECCS systems, though not completely to Western standards, are reasonably comprehensive. Many VVER-440 V213 models operated by former Soviet bloc countries have been upgraded to fully automated Western-style instrumentation and control systems, improving safety to Western levels for accident prevention - but not for accident containment, which is of a modest level compared to Western plants. These reactors are regarded as "safe enough" by Western standards to continue operation without major modifications, though most owners have performed major modifications to bring them up to generally equivalent levels of nuclear safety.

During the 1970s, Finland built two VVER-440 V213 models to Western standards with a large-volume full containment and world-class instrumentation, control standards and an ECCS with multiply redundant and diversified components. In addition, passive safety features such as 900-tonne ice condensers have been installed, making these two units safety-wise the most advanced VVER-440's in the world.

The VVER-1000 type has a definitely adequate Western-style containment, the ECCS is sufficient by Western standards, and instrumentation and control has been markedly improved to Western 1970s-era levels.

Chernobyl disaster

In the Chernobyl disaster the fuel became non-critical when it melted and flowed away from the graphite moderator - however, it took considerable time to cool. The molten core of Chernobyl (that part that was not blown outside the reactor or did not vaporize in the fire) flowed in a channel created by the structure of its reactor building and froze in place before a core-concrete interaction could happen. In the basement of the reactor at Chernobyl, a large "elephant's foot" of congealed core material was found, one example of the freely-flowing corium. Time delay, and prevention of direct emission to the atmosphere (i.e., containment), would have reduced the radiological release. If the basement of the reactor building had been penetrated, the groundwater would be severely contaminated, and its flow could carry the contamination far afield.
The Chernobyl reactor was a RBMK type. The disaster was caused by a power excursion that led to a steam explosion, meltdown and extensive offsite consequences. Operator error and a faulty shutdown system led to a sudden, massive spike in the neutron multiplication rate, a sudden decrease in the neutron period, and a consequent increase in neutron population; thus, core heat flux increased rapidly beyond the design limits of the reactor. This caused the water coolant to flash to steam, causing a sudden overpressure within the reactor pressure vessel (RPV), leading to granulation of the upper portion of the core and the ejection of the upper plenum of said pressure vessel along with core debris from the reactor building in a widely dispersed pattern. The lower portion of the reactor remained somewhat intact; the graphite neutron moderator was exposed to oxygen-containing air; heat from the power excursion in addition to residual heat flux from the remaining fuel rods left without coolant induced oxidation in the moderator and in the opened fuel rods; this in turn evolved more heat and contributed to the melting of more of the fuel rods and the outgassing of the fission products contained therein. The liquefied remains of the melted fuel rods, pulverized concrete and any other objects in the path flowed through a drainage pipe into the basement of the reactor building and solidified in a mass, though the primary threat to the public safety was the dispersed core ejecta, vaporized and gaseous fission products and fuel, and the gasses evolved from the oxidation of the moderator.

Although the Chernobyl accident had dire off-site effects, much of the radioactivity remained within the building. If the building were to fail and dust was to be released into the environment then the release of a given mass of fission products which have aged for almost thirty years would have a smaller effect than the release of the same mass of fission products (in the same chemical and physical form) which had only undergone a short cooling time (such as one hour) after the nuclear reaction has been terminated. However, if a nuclear reaction was to occur again within the Chernobyl plant (for instance if rainwater was to collect and act as a moderator) then the new fission products would have a higher specific activity and thus pose a greater threat if they were released. To prevent a post-accident nuclear reaction, steps have been taken, such as adding neutron poisons to key parts of the basement.

Effects

The effects of a nuclear meltdown depend on the safety features designed into a reactor. A modern reactor is designed both to make a meltdown unlikely, and to contain one should it occur.

In a modern reactor, a nuclear meltdown, whether partial or total, should be contained inside the reactor's containment structure. Thus (assuming that no other major disasters occur) while the meltdown will severely damage the reactor itself, possibly contaminating the whole structure with highly radioactive material, a meltdown alone should not lead to significant radiation release or danger to the public.[22]

In practice, however, a nuclear meltdown is often part of a larger chain of disasters (although there have been so few meltdowns in the history of nuclear power that there is not a large pool of statistical information from which to draw a credible conclusion as to what "often" happens in such circumstances). For example, in the Chernobyl accident, by the time the core melted, there had already been a large steam explosion and graphite fire and major release of radioactive contamination (as with almost all Soviet reactors, there was no containment structure at Chernobyl). Also, before a possible meltdown occurs, pressure can already be rising in the reactor, and to prevent a meltdown by restoring the cooling of the core, operators are allowed to reduce the pressure in the reactor by releasing (radioactive) steam into the environment. This enables them to inject additional cooling water into the reactor again.

Reactor design

Although pressurized water reactors are more susceptible to nuclear meltdown in the absence of active safety measures, this is not a universal feature of civilian nuclear reactors. Much of the research in civilian nuclear reactors is for designs with passive nuclear safety features that may be less susceptible to meltdown, even if all emergency systems failed. For example, pebble bed reactors are designed so that complete loss of coolant for an indefinite period does not result in the reactor overheating. The General Electric ESBWR and Westinghouse AP1000 have passively activated safety systems. The CANDU reactor has two low-temperature and low-pressure water systems surrounding the fuel (i.e. moderator and shield tank) that act as back-up heat sinks and preclude meltdowns and core-breaching scenarios.[19] Liquid fueled reactors can be stopped by draining the fuel into tankage which not only prevents further fission but draws decay heat away statically, and by drawing off the fission products (which are the source of post-shutdown heating) incrementally. The ideal is to have reactors that fail-safe through physics rather than through redundant safety systems or human intervention.

Fast breeder reactors are more susceptible to meltdown than other reactor types, due to the larger quantity of fissile material and the higher neutron flux inside the reactor core, which makes it more difficult to control the reaction. This is not true of the Integral Fast Reactor model EBR II,[23] which was explicitly designed to be meltdown-immune. It was tested in April 1986, just before the Chernobyl failure, to simulate loss of coolant pumping power, by switching off the power to the primary pumps. As designed, it shut itself down, in about 300 seconds, as soon as the temperature rose to a point designed as higher than proper operation would require. This was well below the boiling point of the unpressurised liquid metal coolant, which had entirely sufficient cooling ability to deal with the heat of fission product radioactivity, by simple convection. The second test, deliberate shut-off of the secondary coolant loop that supplies the generators, caused the primary circuit to undergo the same safe shutdown. This test simulated the case of a water-cooled reactor losing its steam turbine circuit, perhaps by a leak.

Accidental fires are widely acknowledged to be risk factors that can contribute to a nuclear meltdown.

Nuclear meltdown events

This is a list of the major reactor failures in which meltdown played a role:[24]

United States


SL-1 core damage after a nuclear excursion.
  • BORAX-I was a test reactor designed to explore criticality excursions and observe if a reactor would self limit. In the final test, it was deliberately destroyed and revealed that the reactor reached much higher temperatures than were predicted at the time.[25]
  • The reactor at EBR-I suffered a partial meltdown during a coolant flow test on 29 November 1955.
  • The Sodium Reactor Experiment in Santa Susana Field Laboratory was an experimental nuclear reactor which operated from 1957 to 1964 and was the first commercial power plant in the world to experience a core meltdown in July 1959.
  • Stationary Low-Power Reactor Number One (SL-1) was a United States Army experimental nuclear power reactor which underwent a criticality excursion, a steam explosion, and a meltdown on 3 January 1961, killing three operators.
  • The SNAP8ER reactor at the Santa Susana Field Laboratory experienced damage to 80% of its fuel in an accident in 1964.
  • The partial meltdown at the Fermi 1 experimental fast breeder reactor, in 1966, required the reactor to be repaired, though it never achieved full operation afterward.
  • The SNAP8DR reactor at the Santa Susana Field Laboratory experienced damage to approximately a third of its fuel in an accident in 1969.
  • The Three Mile Island accident, in 1979, referred to in the press as a "partial core melt"[26] led to the total dismantlement of the reactor and the permanent shutdown of that plant.

Soviet Union

Japan

Switzerland

Canada

United Kingdom

France

Czechoslovakia

China Syndrome

For the 1979 film, see The China Syndrome. For The King of Queens episode, see China Syndrome (The King of Queens).
Chernobyl corium lava flows formed by fuel-containing mass in the basement of the plant.[31]

The China syndrome (loss-of-coolant accident) is a hypothetical nuclear reactor operations accident characterized by the severe meltdown of the core components of the reactor, which then burn through the containment vessel, the housing building, then notionally through the crust and body of the Earth until reaching the other side, which in the United States is jokingly referred to as being China.[32][33]

In reality, under a complete loss of coolant scenario, the fast erosion phase of the concrete basement lasts for about an hour and progresses into about one meter depth, then slows to several centimeters per hour, and stops completely when the corium melt cools below the decomposition temperature of concrete (about 1100 °C). Complete melt-through can occur in several days, even through several meters of concrete; the corium then penetrates several meters into the underlying soil, spreads around, cools, and solidifies.[34]

The real scare, however, came from a quote in the 1979 film "The China Syndrome," which stated, "It melts right down through the bottom of the plant-theoretically to China, but of course, as soon as it hits ground water, it blasts into the atmosphere and sends out clouds of radioactivity. The number of people killed would depend on which way the wind was blowing, rendering an area the size of Pennsylvania permanently uninhabitable." The actual threat of this was tested just 12 days after the release of the film when a meltdown at Pennsylvania's Three Mile Island Plant 2 (TMI-2) created a molten core that moved 15 millimeters toward "China" before the core froze at the bottom of the reactor pressure vessel.[35] Thus, the TMI-2 reactor fuel and fission products broached the fuel plates, the melted core itself did not break the containment of the reactor vessel.[36] Hours after the meltdown, concern about hydrogen build-up led operators to release some radioactive gasses into the atmosphere, including gaseous fission products. Release of the fission products led to a temporary evacuation of the surrounding area, but no injuries.

An instance eerily similar to the actual China syndrome quote from the movie occurred during the early stages of the Chernobyl disaster: after the reactor was destroyed and began to burn, the liquid corium mass from the melted core began to breach the concrete floor of the reactor vessel, underneath which lay the bubbler pool (a large water reservoir for the emergency pumps also designed to safely contain steam pipe ruptures). The RBMK had no allowance or planning for core meltdowns, and the imminent interaction of the core mass with the bubbler pool would have produced a massive steam explosion that would have likely destroyed the entire plant and vastly increased the spread and magnitude of the radioactive plume. However, the initial explosion had broken the control circuitry which allowed the pool to be emptied. Three volunteer divers gave their lives to manually operate the valves necessary to drain this pool, and later images of the corium mass in the pipes of the bubbler pool's basement reinforced the heroic necessity of their actions.[37]

History

The system design of the nuclear power plants built in the late 1960s raised questions of operational safety, and raised the concern that a severe reactor accident could release large quantities of radioactive materials into the atmosphere and environment. By 1970, there were doubts about the ability of the emergency core cooling system of a nuclear reactor to prevent a loss of coolant accident and the consequent meltdown of the fuel core; the subject proved popular in the technical and the popular presses.[17] In 1971, in the article Thoughts on Nuclear Plumbing, former Manhattan Project (1942–1946) nuclear physicist Ralph Lapp used the term "China syndrome" to describe a possible burn-through, after a loss of coolant accident, of the nuclear fuel rods and core components melting the containment structures, and the subsequent escape of radioactive material(s) into the atmosphere and environment; the hypothesis derived from a 1967 report by a group of nuclear physicists, headed by W. K. Ergen.[18] In the event, Lapp’s hypothetical nuclear accident was cinematically adapted as The China Syndrome (1979).

Lie point symmetry

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