Sustainable landscaping

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Sustainable_landscaping

Sustainable landscaping is a modern type of gardening or landscaping that takes the environmental issue of sustainability into account. According to Loehrlein in 2009 this includes design, construction and management of residential and commercial gardens.

Definition

A sustainable garden is designed to be both attractive and in balance with the local climate and environment and it should require minimal resource inputs. Thus, the design must be “functional, cost-efficient, visually pleasing, environmentally friendly and maintainable". As part of sustainable development, it pays close attention to preserving limited resources, reducing waste, and preventing air, water and soil pollution. Compost, fertilization, integrated pest management, using the right plant in the right place, appropriate use of turf and xeriscaping (water-wise gardening) are all components of sustainable landscaping. 

Benefits

Sustainability can help urban commercial landscaping companies save money. In California, gardens often do not outweigh the cost of inputs like water and labor. However, using appropriately selected and properly sited plants may help to ensure that maintenance costs are lower because of reduced inputs.

• Long lasting
• Reduced water usage and no water run off or puddles
• Minimal use of fertilizers and pesticides
• Use of green waste
• Conservation of energy and resources

Issues

Sustainability issues for landscaping include:

• Carbon sequestration
• Climate change
• Water conservation
• Energy usage

Non-sustainable practices include:

• Consumption of non-renewable resources
• Greenhouse gas emissions

Solutions

Some of the solutions are:

• Reduction of stormwater run-off through the use of bio-swales, rain gardens and green roofs and walls.
• Reduction of water use in landscapes through design of water-wise garden techniques (sometimes known as xeriscaping)
• Bio-filtering of wastes through constructed wetlands 
• Irrigation using water from showers and sinks, known as gray water 
• Integrated Pest Management techniques for pest control
• Creating and enhancing wildlife habitat in urban environments 
• Energy-efficient garden design in the form of proper placement and selection of shade trees and creation of wind breaks 
• Permeable paving materials to reduce stormwater run-off and allow rain water to infiltrate into the ground and replenish groundwater rather than run into surface water
• Use of sustainably harvested wood, composite wood products for decking and other garden uses, as well as use of plastic lumber 
• Recycling of products, such as glass, rubber from tires and other materials to create landscape products such as paving stones, mulch and other materials
• Soil management techniques, including composting kitchen and yard wastes, to maintain and enhance healthy soil that supports a diversity of soil life
• Integration and adoption of renewable energy, including solar-powered lighting 
• Development of lawn alternatives such as xeriscaping, floral lawns, and meadows.

Proper design

One step to garden design is to do a "sustainability audit". This is similar to a landscape site analysis that is typically performed by landscape designers at the beginning of the design process. Factors such as lot size, house size, local covenants and budgets should be considered. The steps to design include a base plan, site inventory and analysis, construction documents, implementation and maintenance. Of great importance is considerations related to the growing conditions of the site. These include orientation to the sun, soil type, wind flow, slopes, shade and climate, the goal of reducing irrigation and use of toxic substances, and requires proper plant selection for the specific site. 

Sustainable landscaping is not only important because it saves money, it also limits the human impact on the surrounding ecosystem. However, planting species not native to the landscape may introduce invasive plant species as well as new wildlife that was not in the ecosystem before. Altering the ecosystem is a major problem and meeting with an expert with experience with the wildlife and agriculture in the area will help avoid this. 

Irrigation

Mulch may be used to reduce water loss due to evaporation, reduce weeds, minimize erosion, dust and mud problems. Mulch can also add nutrients to the soil when it decomposes. However, mulch is most often used for weed suppression. Over use of mulch can result in harm to the selected plantings. Care must be taken in the source of the mulch, for instance, black walnut trees result in a toxic mulch product. Grass cycling turf areas (using mulching mowers that leave grass clippings on the lawn) will also decrease the amount of fertilizer needed, reduce landfill waste and reduce costs of disposal.

A common recommendation is to adding 2-4 inches of mulch in flower beds and under trees away from the trunk. Mulch should be applied under trees to the dripline (extension of the branches) in lieu of flowers, hostas, turf or other plants that are often planted there. This practice of planting under trees is detrimental to tree roots, especially when such plants are irrigated to an excessive level that harms the tree. One must be careful not to apply mulch to the bark of the tree. It can result in smothering, mold, and to insect depredation.

The practice of xeriscaping or water-wise gardening suggests that placing plants with similar water demands together will save time and low-water or drought tolerant plants would be a smart initial consideration.

A homeowner may consider consulting an accredited irrigation technician/auditor and obtain a water audit of current systems. Drip or sub-surface irrigation may be useful. Using evapotranspiration controllers, soil sensors and refined control panels will reduce water loss. Irrigation heads may need readjustment to avoid sprinkling on sidewalks or streets. Business owners may consider developing watering schedules based on historical or actual weather data and soil probes to monitor soil moisture prior to watering.

An example of sustainable irrigation (Drip Irrigation)

 

Building materials

When deciding what kind of building materials to put on a site it is important to recycle as often as possible, such as for example by reusing old bricks.

It is also important to be careful about what materials you use, especially if you plan to grow food crops. Old telephone poles and railroad ties have usually been treated with a toxic substance called creosote that can leach into the soils.

Sustainably harvested lumber is available, in which ecological, economic and social factors are integrated into the management of trees used for lumber.

Planting selection

One important part of sustainable landscaping is plant selection. Most of what makes a landscape unsustainable is the amount of inputs required to grow a non-native plant on it. What this means is that a local plant, which has adapted to local climate conditions will require less work to flourish. Instead, drought-tolerant plants like succulents and cacti are better suited to survive. 

Plants used as windbreaks can save up to 30% on heating costs in winter. They also help with shading a residence or commercial building in summer, create cool air through evapo-transpiration and can cool hardscape areas such as driveways and sidewalks.

Irrigation is an excellent end-use option in greywater recycling and rainwater harvesting systems, and a composting toilet can cover (at least) some of the nutrient requirements. Not all fruit trees are suitable for greywater irrigation, as reclaimed greywater is typically of high pH and acidophile plants don't do well in alkaline environments.

Energy conservation may be achieved by placing broadleaf deciduous trees near the east, west and optionally north-facing walls of the house. Such selection provides shading in the summer while permitting large amounts of heat-carrying solar radiation to strike the house in the winter. The trees are to be placed as closely as possible to the house walls. As the efficiency of photovoltaic panels and passive solar heating is sensitive to shading, experts suggest the complete absence of trees near the south side.

Another choice would be that of a dense vegetative fence composed of evergreens (e.g. conifers) near that side from which cold continental winds blow and also that side from which the prevailing winds blow. Such choice creates a winter windbreak that prevents low temperatures outside the house and reduces air infiltration towards the inside. Calculations show that placing the windbreak at a distance twice the height of the trees can reduce the wind velocity by 75%.

The above vegetative arrangements come with two disadvantages. Firstly, they minimize air circulation in summer although in many climates heating is more important and costly than cooling, and, secondly, they may affect the efficiency of photovoltaic panels. However, it has been estimated that if both arrangements are applied properly, they can reduce the overall house energy usage by up to 22%.

 

Sustainable lawns

An example of a sustainable lawn

 

Lawns are typically the center point of any landscape. While there are many different species of grass, only a limited amount are considered sustainable. Knowing the climate around the landscape is ideal for saving water and being sustainable. For example, in southern California having a grass lawn of tall fescue will typically need upwards of 1,365 cubic metres (360,500 US gal) of water. A lawn in the same place made up of mixed beds with various trees, shrubs, and ground cover will normally need 202 cubic metres (53,300 US gal) of water. Having gravel, wood chips or bark, mulch, rubber mulch, artificial grass, patio, wood or composite deck, rock garden, or a succulent garden are all sustainable landscape techniques. Other species of plants other than grass that can take up a lawn are lantana, clover, creeping ivy, creeping thyme, oregano, rosemary hedges, silver pony foot, moneywort, chamomile, yarrow, creeping lily turf, ice plant, and stone crop.

Maintenance

Pests

It is best to start with pest-free plant materials and supplies and close inspection of the plant upon purchase is recommended. Establishing diversity within the area of plant species will encourage populations of beneficial organisms (e.g. birds, insects), which feed on potential plant pests. Attracting a wide variety of organisms with a variety of host plants has shown to be effective in increasing pollinator presence in agriculture. Because plant pests vary from plant to plant, assessing the problem correctly is half the battle. The owner must consider whether the plant can tolerate the damage caused by the pest. If not, then does the plant justify some sort of treatment? Physical barriers may help. Landscape managers should make use of the Integrated Pest Management to reduce use of pesticides and herbicides. 

Pruning

Proper pruning will increase air circulation and may decrease the likelihood of plant diseases. However, improper pruning is detrimental to shrubs and trees.

Programs

There are several programs in place that are open to participation by various groups. For example, the Audubon Cooperative Sanctuary Program for golf courses, the Audubon Green Neighborhoods Program, and the National Wildlife Federation’s Backyard Habitat Program, to name a few.

The Sustainable Sites Initiative, began in 2005, provides a points-based certification for landscapes, similar to the LEED program for buildings operated by the Green Building Council. It has guidelines and performance benchmarks.

Metamodeling

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Metamodeling

 

Example of a Geologic map information meta-model, with four types of meta-objects, and their self-references.

 

A metamodel or surrogate model is a model of a model, and metamodeling is the process of generating such metamodels. Thus metamodeling or meta-modeling is the analysis, construction and development of the frames, rules, constraints, models and theories applicable and useful for modeling a predefined class of problems. As its name implies, this concept applies the notions of meta- and modeling in software engineering and systems engineering. Metamodels are of many types and have diverse applications.

Overview

A metamodel/ surrogate model is a model of the model, i.e. a simplified model of an actual model of a circuit, system, or software like entity. Metamodel can be a mathematical relation or algorithm representing input and output relations. A model is an abstraction of phenomena in the real world; a metamodel is yet another abstraction, highlighting properties of the model itself. A model conforms to its metamodel in the way that a computer program conforms to the grammar of the programming language in which it is written. Various types of metamodels include polynomial equations, neural network, Kriging, etc. "Metamodeling" is the construction of a collection of "concepts" (things, terms, etc.) within a certain domain. Metamodeling typically involves studying the output and input relationships and then fitting right metamodels to represent that behavior. 

Common uses for metamodels are:

• As a schema for semantic data that needs to be exchanged or stored
• As a language that supports a particular method or process
• As a language to express additional semantics of existing information
• As a mechanism to create tools that work with a broad class of models at run time
• As a schema for modeling and automatically exploring sentences of a language with applications to automated test synthesis
• As an approximation of a higher-fidelity model for use when reducing computational cost is necessary

Because of the "meta" character of metamodeling, both the praxis and theory of metamodels are of relevance to metascience, metaphilosophy, metatheories and systemics, and meta-consciousness. The concept can be useful in mathematics, and has practical applications in computer science and computer engineering/software engineering. The latter are the main focus of this article.

Topics

Meta-Object Facility Illustration.

 

A US FEA Business reference model.

 

Example of an ontology.

 

A DoDAF metamodel.

 

Definition

In software engineering, the use of models is an alternative to more common code-based development techniques. A model always conforms to a unique metamodel. One of the currently most active branch of Model Driven Engineering is the approach named model-driven architecture proposed by OMG. This approach is based on the utilization of a language to write metamodels called the Meta Object Facility or MOF. Typical metamodels proposed by OMG are UML, SysML, SPEM or CWM. ISO has also published the standard metamodel ISO/IEC 24744. All the languages presented below could be defined as MOF metamodels. 

Metadata modeling

Metadata modeling is a type of metamodeling used in software engineering and systems engineering for the analysis and construction of models applicable and useful to some predefined class of problems.

Model transformations

One important move in model-driven engineering is the systematic use of model transformation languages. The OMG has proposed a standard for this called QVT for Queries/Views/Transformations. QVT is based on the meta-object facility or MOF. Among many other model transformation languages (MTLs), some examples of implementations of this standard are AndroMDA, VIATRA, Tefkat, MT, ManyDesigns Portofino. 

Relationship to ontologies

Meta-models are closely related to ontologies. Both are often used to describe and analyze the relations between concepts:

• Ontologies: express something meaningful within a specified universe or domain of discourse by utilizing a grammar for using vocabulary. The grammar specifies what it means to be a well-formed statement, assertion, query, etc. (formal constraints) on how terms in the ontology’s controlled vocabulary can be used together.
• Meta-modeling: can be considered as an explicit description (constructs and rules) of how a domain-specific model is built. In particular, this comprises a formalized specification of the domain-specific notations. Typically, metamodels are – and always should follow - a strict rule set. "A valid metamodel is an ontology, but not all ontologies are modeled explicitly as metamodels".

Types of metamodels

For software engineering, several types of models (and their corresponding modeling activities) can be distinguished:

• Metadata modeling (MetaData model)
• Meta-process modeling (MetaProcess model)
• Executable meta-modeling (combining both of the above and much more, as in the general purpose tool Kermeta)
• Model transformation language (see below)
• Polynomial metamodels
• Neural network metamodels
• Kriging metamodels
• Piecewise polynomial (spline) metamodels
• Gradient-enhanced kriging (GEK)

Zoos of metamodels

A library of similar metamodels has been called a Zoo of metamodels. There are several types of meta-model zoos. Some are expressed in ECore. Others are written in MOF 1.4 – XMI 1.2. The metamodels expressed in UML-XMI1.2 may be uploaded in Poseidon for UML, a UML CASE tool.

Metamodeling software

• Surrogate Modeling Toolbox (SMT: https://github.com/SMTorg/smt): is a Python package that contains a collection of surrogate modeling methods, sampling techniques, and benchmarking functions. This package provides a library of surrogate models that is simple to use and facilitates the implementation of additional methods. SMT is different from existing surrogate modeling libraries because of its emphasis on derivatives, including training derivatives used for gradient-enhanced modeling, prediction derivatives, and derivatives with respect to the training data. It also includes new surrogate models that are not available elsewhere: kriging by partial-least squares reduction and energy-minimizing spline interpolation.

Method engineering

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Method_engineering

Example of a Method Engineering Process. This figure provides a process-oriented view of the approach used to develop prototype IDEF9 method concepts, a procedure, and candidate graphical and textual language elements.

 

Method engineering in the "field of information systems is the discipline to construct new methods from existing methods". It focuses on "the design, construction and evaluation of methods, techniques and support tools for information systems development".

Furthermore, method engineering "wants to improve the usefulness of systems development methods by creating an adaptation framework whereby methods are created to match specific organisational situations".

Types

Computer aided method engineering

The meta-process modeling process is often supported through software tools, called computer aided method engineering (CAME) tools, or MetaCASE tools (Meta-level Computer Assisted Software Engineering tools). Often the instantiation technique "has been utilised to build the repository of Computer Aided Method Engineering environments". There are many tools for meta-process modeling.

Method tailoring

In the literature, different terms refer to the notion of method adaptation, including 'method tailoring', 'method fragment adaptation' and 'situational method engineering'. Method tailoring is defined as:

A process or capability in which human agents through responsive changes in, and dynamic interplays between contexts, intentions, and method fragments determine a system development approach for a specific project situation.

Potentially, almost all agile methods are suitable for method tailoring. Even the DSDM method is being used for this purpose and has been successfully tailored in a CMM context. Situation-appropriateness can be considered as a distinguishing characteristic between agile methods and traditional software development methods, with the latter being relatively much more rigid and prescriptive. The practical implication is that agile methods allow project teams to adapt working practices according to the needs of individual projects. Practices are concrete activities and products that are part of a method framework. At a more extreme level, the philosophy behind the method, consisting of a number of principles, could be adapted.

Situational method engineering

Situational method engineering is the construction of methods which are tuned to specific situations of development projects. It can be described as the creation of a new method by

1. selecting appropriate method components from a repository of reusable method components,
2. tailoring these method components as appropriate, and
3. integrating these tailored method components to form the new situation-specific method.

This enables the creation of development methods suitable for any development situation. Each system development starts then, with a method definition phase where the development method is constructed on the spot.

In case of mobile business development, there are methods available for specific parts of the business model design process and ICT development. Situational method engineering can be used to combine these methods into one unified method that adopts the characteristics of mobile ICT services. 

Method engineering process

The developers of the IDEF modeling languages, Richard J. Mayer et al. (1995), have developed an early approach to method engineering from studying common method engineering practice and experience in developing other analysis and design methods. The following figure provides a process-oriented view of this approach. This image uses the IDEF3 Process Description Capture method to describe this process where boxes with verb phrases represent activities, arrows represent precedence relationships, and "exclusive or" conditions among possible paths are represented by the junction boxes labeled with an "X.".

This image provides a general overview of the IDEF Method engineering process approach.

According to this approach there are three basic strategies in method engineering:

1. Reuse: one of the basic strategies of methods engineering is reuse. Whenever possible, existing methods are adopted.
2. Tailormade: find methods that can satisfy the identified needs with minor modification. This option is an attractive one if the modification does not require a fundamental change in the basic concepts or design goals of the method.
3. New development: Only when neither of these options is viable should method designers seek to develop a new method.

This basic strategies can be developed in a similar process of concept development.

Knowledge engineering approach

A knowledge engineering approach is the predominant mechanism for method enhancement and new method development. In other words, with very few exceptions, method development involves isolating, documenting, and packaging existing practice for a given task in a form that promotes reliable success among practitioners. Expert attunements are first characterized in the form of basic intuitions and method concepts. These are often initially identified through analysis of the techniques, diagrams, and expressions used by experts. These discoveries aid in the search for existing methods that can be leveraged to support novice practitioners in acquiring the same attunements and skills.

New method development is accomplished by establishing the scope of the method, refining characterizations of the method concepts and intuitions, designing a procedure that provides both task accomplishment and basic apprenticeship support to novice practitioners, and developing a language(s) of expression. Method application techniques are then developed outlining guidelines for use in a stand-alone mode and in concert with other methods. Each element of the method then undergoes iterative refinement through both laboratory and field testing.

Method language design process

The method language design process is highly iterative and experimental in nature. Unlike procedure development, where a set of heuristics and techniques from existing practice can be identified, merged, and refined, language designers rarely encounter well-developed graphical display or textual information capture mechanisms. When potentially reusable language structures can be found, they are often poorly defined or only partially suited to the needs of the method.

A critical factor in the design of a method language is clearly establishing the purpose and scope of the method. The purpose of the method establishes the needs the method must address. This is used to determine the expressive power required of the supporting language. The scope of the method establishes the range and depth of coverage which must also be established before one can design an appropriate language design strategy. Scope determination also involves deciding what cognitive activities will be supported through method application. For example, language design can be confined to only display the final results of method application (as in providing IDEF9 with graphical and textual language facilities that capture the logic and structure of constraints). Alternatively, there may be a need for in-process language support facilitating information collection and analysis. In those situations, specific language constructs may be designed to help method practitioners organize, classify, and represent information that will later be synthesized into additional representation structures intended for display.

With this foundation, language designers begin the process of deciding what needs to be expressed in the language and how it should be expressed. Language design can begin by developing a textual language capable of representing the full range of information to be addressed. Graphical language structures designed to display select portions of the textual language can then be developed. Alternatively, graphical language structures may evolve prior to, or in parallel with, the development of the textual language. The sequence of these activities largely depends on the degree of understanding of the language requirements held among language developers. These may become clear only after several iterations of both graphical and textual language design.

Graphical language design

Graphical language design begins by identifying a preliminary set of schematics and the purpose or goals of each in terms of where and how they will support the method application process. The central item of focus is determined for each schematic. For example, in experimenting with alternative graphical language designs for IDEF9, a Context Schematic was envisioned as a mechanism to classify the varying environmental contexts in which constraints may apply. The central focus of this schematic was the context. After deciding on the central focus for the schematic, additional information (concepts and relations) that should be captured or conveyed is identified.

Up to this point in the language design process, the primary focus has been on the information that should be displayed in a given schematic to achieve the goals of the schematic. This is where the language designer must determine which items identified for possible inclusion in the schematic are amenable to graphical representation and will serve to keep the user focused on the desired information content. With this general understanding, previously developed graphical language structures are explored to identify potential reuse opportunities. While exploring candidate graphical language designs for emerging IDEF methods, a wide range of diagrams were identified and explored. Quite often, even some of the central concepts of a method will have no graphical language element in the method.

For example, the IDEF1 Information Modeling method includes the notion of an entity but has no syntactic element for an entity in the graphical language.8. When the language designer decides that a syntactic element should be included for a method concept, candidate symbols are designed and evaluated. Throughout the graphical language design process, the language designer applies a number of guiding principles to assist in developing high quality designs. Among these, the language designer avoids overlapping concept classes or poorly defined ones. They also seek to establish intuitive mechanisms to convey the direction for reading the schematics.

For example, schematics may be designed to be read from left to right, in a bottom-up fashion, or center-out. The potential for clutter or overwhelmingly large amounts of information on a single schematic is also considered as either condition makes reading and understanding the schematic extremely difficult.

Method testing

Each candidate design is then tested by developing a wide range of examples to explore the utility of the designs relative to the purpose for each schematic. Initial attempts at method development, and the development of supporting language structures in particular, are usually complicated. With successive iterations on the design, unnecessary and complex language structures are eliminated.

As the graphical language design approaches a level of maturity, attention turns to the textual language. The purposes served by textual languages range from providing a mechanism for expressing information that has explicitly been left out of the graphical language to providing a mechanism for standard data exchange and automated model interpretation. Thus, the textual language supporting the method may be simple and unstructured (in terms of computer interpretability), or it may emerge as a highly structured, and complex language. The purpose of the method largely determines what level of structure will be required of the textual language.

Formalization and application techniques

As the method language begins to approach maturity, mathematical formalization techniques are employed so the emerging language has clear syntax and semantics. The method formalization process often helps uncover ambiguities, identify awkward language structures, and streamline the language.

These general activities culminate in a language that helps focus user attention on the information that needs to be discovered, analyzed, transformed, or communicated in the course of accomplishing the task for which the method was designed. Both the procedure and language components of the method also help users develop the necessary skills and attunements required to achieve consistently high quality results for the targeted task.

Once the method has been developed, application techniques will be designed to successfully apply the method in stand-alone mode as well as together with other methods. Application techniques constitute the "use" component of the method which continues to evolve and grow throughout the life of the method. The method procedure, language constructs, and application techniques are reviewed and tested to iteratively refine the method.

Problem structuring methods

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Problem_structuring_methods

Problem structuring methods (PSMs) are a group of techniques used to model or to map the nature or structure of a situation or state of affairs that some people want to change. PSMs are usually used by a group of people in collaboration (rather than by a solitary individual) to create a consensus about, or at least to facilitate negotiations about, what needs to change. Some widely adopted PSMs include soft systems methodology, the strategic choice approach, and strategic options development and analysis (SODA).

Unlike some problem solving methods that assume that all the relevant issues and constraints and goals that constitute the problem are defined in advance or are uncontroversial, PSMs assume that there is no single uncontested representation of what constitutes the problem.

PSMs are mostly used with groups of people, but PSMs have also influenced the coaching and counseling of individuals.

History

The term "problem structuring methods" as a label for these techniques began to be used in the 1980s in the field of operations research, especially after the publication of the book Rational Analysis for a Problematic World: Problem Structuring Methods for Complexity, Uncertainty and Conflict. Some of the methods that came to be called PSMs had been in use since the 1960s.

Thinkers who later came to be recognized as significant early contributors to the theory and practice of PSMs include:

• Horst Rittel and Melvin M. Webber
• Russell L. Ackoff
• Peter Checkland
• Colin Eden and Fran Ackermann
• Robert L. Flood and Michael C. Jackson
• Jonathan Rosenhead and John Mingers

Types of situations that call for PSMs

In discussions of problem structuring methods, it is common to distinguish between two different types of situations that could be considered to be problems. Rittel and Webber's distinction between tame problems and wicked problems (Rittel & Webber 1973) is a well known example of such types. The following table lists similar (but not exactly equivalent) distinctions made by a number of thinkers between two types of "problem" situations, which can be seen as a continuum between a left and right extreme:

Different types of situations, and thinkers who named them

Thinker	Left extreme	Right extreme
Rittel & Webber	Tame problem	Wicked problem
Herbert A. Simon	Programmed decision	Non-programmed decision
Russell L. Ackoff	Puzzle / Problem	Mess
Jerome Ravetz	Technical problem	Practical problem
Ronald Heifetz	Technical challenge	Adaptive challenge
Peter Checkland	Hard systems	Soft systems
Donald Schön	The high ground	The swamp
Barry Johnson	Problems to solve	Polarities to manage

Tame problems (or puzzles or technical challenges) have relatively precise, straightforward formulations that are often amenable to solution with some predetermined technical fix or algorithm. It is clear when these situations have changed in such a way that the problem can be called solved.

Wicked problems (or messes or adaptive challenges) have multiple interacting issues with multiple stakeholders and uncertainties and no definitive formulation. These situations are complex and have no stopping rule and no ultimate test of a solution.

PSMs were developed for situations that tend toward the wicked or "soft" side, when methods are needed that assist argumentation about, or that generate mutual understanding of multiple perspectives on, a complex situation. Other problem solving methods are better suited to situations toward the tame or "hard" side where a reliable and optimal solution is needed to a problem that can be clearly and uncontroversially defined. 

Characteristics

Problem structuring methods constitute a family of approaches that have differing purposes and techniques, and many of them had been developed independently before people began to notice their family resemblance. Several scholars have noted the common and divergent characteristics among PSMs. 

Eden and Ackermann identified four characteristics that problem structuring methods have in common:

1. The methods focus on creating "a model that is populated with data that is specific to the problem situation". These cause–effect models can be analyzed (albeit in different ways by different methods), and the models are intended to facilitate conversation and negotiation between the participants.
2. The methods seek to increase the overall productivity of group processes. Productivity includes creating better agreements that are more likely to be implemented, and realizing (to the extent possible in the given situation) ideals such as communicative rationality and procedural justice.
3. The methods emphasize that the facilitation of effective group processes requires some attention to, and open conversation about, power and politics within and between organizations. Power and politics can become especially important when major change is being proposed.
4. The methods provide techniques and skills for facilitation of group processes, and they appreciate that such techniques and skills are essential for effective sensemaking, systems modeling, and participative decision-making. People who use PSMs must pay attention to what group facilitators call process skills (guiding interactions between people through nonlinear applications of the methods) and content skills (helping people build sufficiently comprehensive models of the given situation).

Rosenhead provided another list of common characteristics of PSMs, formulated in a more prescriptive style:

• Seek solutions which satisfice on separate dimensions rather than seeking an optimal decision on a single dimension.
• Integrate hard and soft (quantitative and qualitative) data with social judgments.
• Produce models that are as transparent as possible to and that clarify conflicts of interpretation, rather than hiding conflicts behind neutral technical language.
• Consider people to be agents actively involved in the decision-making process, rather than as passive objects to be modeled or ignored.
• Facilitate the problem structuring process from the bottom-up as much as possible, not only top-down from formal organizational leadership.
• Aim to preserve options in the face of unavoidable uncertainty, rather than to base decisions on a prediction of the future.

An early literature review of problem structuring proposed grouping the texts reviewed into "four streams of thought" that describe some major differences between methods:

• the checklist stream, which is step-by-step technical problem solving (not problem structuring as it came to be defined in PSMs, so this stream does not apply to PSMs),
• the definition stream, which is primarily modeling of relationships between variables, as described by Ackoff and others,
• the science research stream which emphasizes doing field research and gathering quantitative data, and
• the people stream, which "regards the definition of problems as a function of people's perceptions" as described by Checkland, Eden, and others.

Compared to large group methods

Mingers and Rosenhead have noted that there are similarities and differences between PSMs and large group methods such as Future Search, Open Space Technology, and others. PSMs and large group methods both bring people together to talk about, and to share different perspectives on, a situation or state of affairs that some people want to change. However, PSMs always focus on creating a sufficiently rigorous conceptual model or cognitive map of the situation, whereas large group methods do not necessarily emphasize modeling, and PSMs are not necessarily used with large groups of people.

Compared to participatory rural appraisal

There is significant overlap or shared characteristics between PSMs and some of the techniques used in participatory rural appraisal (PRA). Mingers and Rosenhead pointed out that in situations where people have low literacy, the nonliterate (oral and visual) techniques developed in PRA would be a necessary complement to PSMs, and the approaches to modeling in PSMs could be (and have been) used by practitioners of PRA.

Applications

In 2004, Mingers and Rosenhead published a literature review of papers that had been published in scholarly journals and that reported practical applications of PSMs. Their literature survey covered the period up to 1998, which was "relatively early in the development of interest in PSMs", and categorized 51 reported applications under the following application areas: general organizational applications; information systems; technology, resources, planning; health services; and general research. Examples of applications reported included: designing a parliamentary briefing system, modeling the San Francisco Zoo, developing a business strategy and information system strategy, planning livestock management in Nepal, regional planning in South Africa, modeling hospital outpatient services, and eliciting knowledge about pesticides.

Technology and software

PSMs are a general methodology and are not necessarily dependent on electronic information technology, but PSMs do rely on some kind of shared display of the models that participants are developing. The shared display could be flip charts, a large whiteboard, Post-it notes on the meeting room walls, and/or a personal computer connected to a video projector. After PSMs have been used in a group work session, it is normal for a record of the session's display to be shared with participants and with other relevant people.

Software programs for supporting problem structuring include Banxia Decision Explorer and Group Explorer, which implement cognitive mapping for strategic options development and analysis (SODA), and Compendium, which implements IBIS for dialogue mapping and related methods; a similar program is called Wisdom. Such software can serve a variety of functions, such as simple technical assistance to the group facilitator during a single event, or more long-term online group decision support systems. 

Some practitioners prefer not to use computers during group work sessions because of the effect they have on group dynamics, but such use of computers is standard in some PSMs such as SODA^[27] and dialogue mapping, in which computer display of models or maps is intended to guide conversation in the most efficient way.

In some situations additional software that is not used only for PSMs may be incorporated into the problem structuring process; examples include spreadsheet modeling, system dynamics software or geographic information systems. Some practitioners, who have focused on building system dynamics simulation models with groups of people, have called their work group model building (GMB) and have concluded "that GMB is another PSM".^[32] GMB has also been used in combination with SODA.

Clinical formulation

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Clinical_formulation

A clinical formulation, also known as case formulation and problem formulation, is a theoretically-based explanation or conceptualisation of the information obtained from a clinical assessment. It offers a hypothesis about the cause and nature of the presenting problems and is considered an adjunct or alternative approach to the more categorical approach of psychiatric diagnosis. In clinical practice, formulations are used to communicate a hypothesis and provide framework for developing the most suitable treatment approach. It is most commonly used by clinical psychologists and psychiatrists and is deemed to be a core component of these professions. Mental health nurses and social workers may also use formulations.

 

 

Types of formulation

Different psychological schools or models utilize clinical formulations, including cognitive behavioral therapy (CBT) and related therapies: systemic therapy, psychodynamic therapy, and applied behavior analysis. The structure and content of a clinical formulation is determined by the psychological model. Most systems of formulation contain the following broad categories of information: symptoms and problems; precipitating stressors or events; predisposing life events or stressors; and an explanatory mechanism that links the preceding categories together and offers a description of the precipitants and maintaining influences of the person's problems.

Behavioral case formulations used in applied behavior analysis and behavior therapy are built on a rank list of problem behaviors, from which a functional analysis is conducted, sometimes based on relational frame theory. Such functional analysis is also used in third-generation behavior therapy or clinical behavior analysis such as acceptance and commitment therapy and functional analytic psychotherapy. Functional analysis looks at setting events (ecological variables, history effects, and motivating operations), antecedents, behavior chains, the problem behavior, and the consequences, short- and long-term, for the behavior.

A model of formulation that is more specific to CBT is described by Jacqueline Persons. This has seven components: problem list, core beliefs, precipitants and activating situations, origins, working hypothesis, treatment plan, and predicted obstacles to treatment. 

A psychodynamic formulation would consist of a summarizing statement, a description of nondynamic factors, description of core psychodynamics using a specific model (such as ego psychology, object relations or self psychology), and a prognostic assessment which identifies the potential areas of resistance in therapy.

One school of psychotherapy which relies heavily on the formulation is cognitive analytic therapy (CAT). CAT is a fixed-term therapy, typically of around 16 sessions. At around session four, a formal written reformulation letter is offered to the patient which forms the basis for the rest of the treatment. This is usually followed by a diagrammatic reformulation to amplify and reinforce the letter.

Many psychologists use an integrative psychotherapy approach to formulation. This is to take advantage of the benefits of resources from each model the psychologist is trained in, according to the patient's needs.

Critical evaluation of formulations

The quality of specific clinical formulations, and the quality of the general theoretical models used in those formulations, can be evaluated with criteria such as:

• Clarity and parsimony: Is the model understandable and internally consistent, and are key concepts discrete, specific, and non-redundant?
• Precision and testability: Does the model produce testable hypotheses, with operationally defined and measurable concepts?
• Empirical adequacy: Are the posited mechanisms within the model empirically validated?
• Comprehensiveness and generalizability: Is the model holistic enough to apply across a range of clinical phenomena?
• Utility and applied value: Does it facilitate shared meaning-making between clinician and client, and are interventions based on the model shown to be effective?

Formulations can vary in temporal scope from case-based to episode-based or moment-based, and formulations may evolve during the course of treatment. Therefore, ongoing monitoring, testing, and assessment during treatment are necessary: monitoring can take the form of session-by-session progress reviews using quantitative measures, and formulations can be modified if an intervention is not as effective as hoped.

History

Psychologist George Kelly, who developed personal construct theory in the 1950s, noted his complaint against traditional diagnosis in his book The Psychology of Personal Constructs (1955): "Much of the reform proposed by the psychology of personal constructs is directed towards the tendency for psychologists to impose preemptive constructions upon human behaviour. Diagnosis is all too frequently an attempt to cram a whole live struggling client into a nosological category." In place of nosological categories, Kelly used the word "formulation" and mentioned two types of formulation: a first stage of structuralization, in which the clinician tentatively organizes clinical case information "in terms of dimensions rather than in terms of disease entities" while focusing on "the more important ways in which the client can change, and not merely ways in which the psychologist can distinguish him from other persons", and a second stage of construction, in which the clinician seeks a kind of negotiated integration of the clinician's organization of the case information with the client's personal meanings.

Psychologists Hans Eysenck, Monte B. Shapiro, Vic Meyer, and Ira Turkat were also among the early developers of systematic individualized alternatives to diagnosis. Meyer has been credited with providing perhaps the first training course of behaviour therapy based on a case formulation model, at the Middlesex Hospital Medical School in London in 1970. Meyer's original choice of words for clinical formulation were "behavioural formulation" or "problem formulation".