SYSTEMS AND CONTROLS P2

- We must therefore necessarily focus attention only on a portion of the major competing concerns.
- One of the hoped-for results of the use of systems engineering approaches is the development of effective and efficient heuristics for enhanced judgment and choice through effective decision support systems.
- Development of performance objectives for quality systems is important, since evaluation of the logical soundness and performance of a system can be determined by measuring achievement of these objectives with and without the system.
- The section continues with leadership and training requirements for use of the resulting system and the impact of these requirements upon design considerations.
- While it is doubtless true that not every design process should, could, or would precisely follow each component in the detailed phases outlined here, we feel that this approach to systems design is sufficiently robust and generic that it can be used as a normative model of the design process and as a guide to the structuring and implementation of appropriate systems evaluation practices..
- At the other extreme of the cognitive inquiry scale are the highly analytical, theoretical, and experimental approaches of the mathematical, physical, and engi- neering sciences.
- One of the major challenges in system design engineering is to develop processes that are appropriate for a variety of process users, some of whom may approach the design issue from a skill-based perspective, some from a rule-based perspective, and some from a knowledge-based perspective..
- Ultimate effectiveness involves user acceptability of the resulting system, and evaluation of this process effectiveness will often involve testing and evaluation in the environment, or at least a closely simulated model of the environment, in which the system would be potentially deployed..
- The potential benefits of systems engineering approaches to design can be interpreted as attributes or criteria for evaluation of the design approach itself.
- Explicit evaluation of attribute achievement is a very important part of the overall systemic design process.
- An evaluation methodology that may be incorporated with or used independently of the design framework.
- Supports a variety of cognitive skills, styles, and knowledge of the humans who must use the system.
- Assists users of the system to develop and use their own cognitive skills, styles, and knowledge.
- One of the initial goals in systems design engineering is to obtain the conceptual specifications for a product such that development of the system will be based on customer or client information, objectives, and existing situations and needs.
- It is generally necessary that design information be described in ways that lead to effective structuring of the design problem.
- Not all of the performance objectives for quality systems engineering will be, or need be, fully attained in all design instances, but it is generally true that the quality of a system or of a systems design process necessarily improves as more and more of these objectives are attained.
- Measures of quality of the resulting system, and therefore systems design process quality, may be obtained by assessing the degree of achievement of these performance criteria by the resulting system, generally in an operational environment.
- In this way, an evaluation of the effectiveness of a design decision support system may be conducted..
- We are able to describe a large number of situations using elements or features of the three-component taxonomy described earlier.
- The structural and functional properties of such a system, or of the design process itself, must be described in order that a purposeful evaluation can be accomplished.
- The evaluation methodology to be described is useful, therefore, as a part or phase of the design process..
- This must be accomplished in order to translate operational deployment needs, activities, and objectives into requirements specifications if, for example, that is the phase of the systems engineering design effort under consideration..
- Among the many objectives of the requirements specifications phase of systems engineering are the following:.
- including identification of needs, constraints, alterables, and stakeholder groups associated with operational deployment of the system or the systemic process 2.
- To estimate expected effectiveness improvement or benefits due to the use of the system or.
- To determine the extent of tolerable operational environment alteration due to use of the system or systemic process.
- To determine the most appropriate roles for the system or systemic process to perform within the context of the planning, design, or decision situation and operational environment under consideration.
- To estimate potential leadership requirements for use of the final system itself 15.
- To estimate the qualifications required of the design team 17.
- To determine political acceptability and institutional constraints affecting use of an aided support process, and those of the system itself.
- To determine potential requirements for contractor availability after completion of devel- opment and operational tests for additional needs determined by the user group, perhaps as a result of the evaluation effort.
- A design team is then selected to implement the next phase of the system life cycle.
- This discussion emphasizes the inherently coupled nature of these phases of the system life cycle and illustrates why it is not reasonable to consider the phases as if they are uncoupled..
- The preliminary conceptual design phase includes specification of the mathematical and behavioral content and associated algorithms for the system or process that should ultimately result from the effort, as well as the possible need for computer support to implement these.
- To determine the specific leadership requirements for use of the system in the operational environment extant.
- To determine the specific type of output and interpretation of the output to be obtained from the system or process that will result from the design procedure.
- This phase is based on the products of the preliminary conceptual design phase, which should result in a common understanding among all interested parties about the planning and decision support design effort concerning the following:.
- The structure of the operational environment in which plans, designs, and decisions are made 3.
- What implementation, political acceptability, and institutional constraints affect the use of the system or process.
- What specific analysis algorithms will be used in the system or process and how these al- gorithms will be interconnected to form the methodological construction of the system or process.
- To conduct control group or operational (simulated operational) tests of the system and make minor changes in the aid as a result of the tests.
- To complete detailed design and associated testing of a prototype system based on the results of the previous phase.
- The products of this phase are detailed guides to use of the system as well as, of course, the prototype system itself.
- The description of system usage and leadership topics should be addressed in terms of the analytic and behavioral constructs of the system and the resulting process, as well as in terms of operational environment situation concerns.
- Time available from determination of an appropriate plan, design, or decision to implemen- tation of the plan, design, or decision.
- It is especially important that the portion of this phase that concerns implementation of the prototype system specifically address important questions concerning cognitive style and organizational differ- ences among parties at interest and institutions associated with the design effort.
- Stakeholder under- standing of environmental changes and side effects that will result from use of the system is critical for ultimate success.
- Evaluation of the system in accordance with evaluation criteria, determined in the requirements specification phase and modified in the subsequent two design phases, is accomplished in the fourth phase of systems development.
- The evaluation effort must be adapted to other phases of the design effort so that it becomes an integral functional part of the overall design process.
- To identify criteria on which the success of the system or process may be judged.
- To determine effectiveness of the system in terms of success criteria.
- To determine performance-objective achievement of the system 6.
- To determine behavioral or human-factor effectiveness of the system 7.
- To determine the most useful strategy for employment of the existing system 8.
- To determine user-group acceptance of the system.
- To suggest refinements in existing systems for greater effectiveness of the process in which the new system has been embedded.
- To evaluate the effectiveness of the system or process.
- These objectives are obtained from a critical evaluation issue specification or evaluation need spec- ification, which is the first or problem-definition step of the evaluation methodology.
- Generally, the critical issues for evaluation are minor adaptations of the elements that are present in the requirements specifications step of the design process outlined in the previous section.
- An important by- product of evaluation is the determination of ultimate performance limitations and the establishment of a protocol and procedure for use of the system that results in maximum user-group satisfaction..
- A report is written concerning results of the evaluation process, especially those factors relating to user group satisfaction with the designed system.
- Section 26.5.6 will present additional details of the methodologies framework for evaluation..
- These have applicability to cases where evaluation is a separate and independent effort as well as cases where it is one of the phases of the design process..
- This must be accomplished in such a way that all user groups obtain adequate instructions in use of the system and complete operating and maintenance documentation and instructions.
- Specific objectives for the operational deployment phase of the system design effort are.
- To accomplish final design of the system.
- To provide for continuous monitoring of post-implementation effectiveness of the system and the process into which the system is embedded.
- To provide for redesign of the system as indicated by effectiveness monitoring.
- To provide proper training and leadership for successful continued operational use of the system.
- To identify barriers to successful implementation of the final design product 7.
- of the system.
- The actual use, as contrasted with potential usefulness, of a system is directly dependent on the value that the user group of stakeholders associates with use of the system and the resulting process in an operational environment.
- This in turn is dependent, in part, on how well the system satisfies per- formance objectives and on how well it is able to cope with one or more of the pathologies or pitfalls of planning, design, and/or decision-making under potentially stressful operational environment conditions..
- Success in this is, however, strongly dependent on adroitness in use of the system.
- A systemic process depends on the system, the operational environment, and leadership associated with use of the system.
- Establishing criteria on which the success of the system may be judged 3.
- Determining the effectiveness of the support in terms of these criteria.
- Determining the most useful strategy for employment of an existing system and potential improvements such that effectiveness of the newly implemented system and the overall pro- cess might be improved.
- The lowest-level objectives contribute to satisfaction of the 10 performance objectives for systems engineering and systems design outlined in Section 26.3.
- They concern the algorithmic effectiveness or performance objective achievement of the system, the behavioral or human factor effectiveness of the system in the operational environment, and the system efficacy.
- Each of these three elements become top level criteria or attributes and each should be evaluated to determine evaluation of the system itself..
- Attainment of each of these criteria by the system may be measured by observation of the system within the operational environment and by test instruments and surveys of user groups involved with the op- erational system and process..
- Achievement of these objectives is measured by logical soundness of the operational system and.
- A system may be well structured algorithmically in the sense of achieving a high degree of satisfaction of the performance objectives, yet the process incorporating the system may seriously violate behav- ioral and human factor sensibilities.
- and the present sophistication, attitude, and past experience of the user group and its management with similar sys- tems and processes.
- Two of the three first-level evaluation criteria concern algorithmic effectiveness or performance- objective achievement and behavioral or human-factors effectiveness.
- Thus, evaluation of the efficacy of a system and the associated process is important in determining the service support value of the process.
- (2) Recordkeeping and retrospective improvements to systems and processes are enhanced by the availability of well-documented constructions of planning and decision situations and communicable explanations of the rationale for the results of using the system..
- The value of the service support provided by a system will be dependent on the quality of the user's guide and its usefulness to potential users of the system..
- While these last three service support measures are not of special significance with respect to justification of the need for a system, they may be important in determining operational usage and, therefore, operational effectiveness of a system and the associated process..
- Several special evaluation test instruments to satisfy test requirements and measure achievement of the evaluation criteria will generally need to be developed.
- selection of appropriate scenarios that affect use of the system, use of the system subject to these scenarios by a test group, and completion of evaluation questionnaires.
- and questionnaires and interviews with operational users of the system..
- Intentional redundancy should be provided to allow correlation of results obtained from the test instruments to ensure maximum supportability and reliability of the facts and opinions to be obtained from test procedures..
- The evaluation team should take advantage of every opportunity to observe use of the system within the operational environment.
- Questions specific to a given evaluation are determined after study of the particular situation and the system being evaluated.
- One of the important concerns in evaluation is that of those parts of the efficacy evaluation that deal with various "abilities".
- Provide an objective communicable framework that allows identification, formulation, and display of the structure of the issue under consideration, as well as the rationale of the choice process.
- There are a number of potential benefits of the systems approach that should follow high achievement of each of the criteria for effective systems design processes.
- Systems Engineering: The Journal of the National Council on Systems Engineering July/September 1994).

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