Functional analysis and modeling definition of Functional analysis and modeling in the Free Online Encyclopedia.

Functional analysis and modeling (engineering)

The discipline that addresses the activities that a system, a software, or an organization must perform to achieve its desired outputs; that is, what transformations are necessary to turn the available inputs into the desired outputs. Additional considerations include the flow of data or items between functions, the processing instructions that are available to guide the transformations, and the control logic that dictates the activation and termination of functions. Functional analysis diagrams have been developed to capture some or all of these concepts.

Functional analysis is performed in systems engineering, software systems engineering, and business process reengineering as a portion of the design process. These design processes typically involve the steps of requirements definition and analysis, functional analysis, physical or resource definition, and operational analysis. This last step of operational analysis involves the marriage of functions with resources to determine if the requirements are met. The concept of examining the logical architecture via functional analysis concurrent with the development of the physical architecture has become a well-accepted principle in the related fields of systems engineering, software engineering, and business process reengineering. See Reengineering, Software engineering, Systems engineering

Elements

There are four elements to be addressed by any specific functional analysis approach. First, the functions are represented as a hierarchical decomposition, in which there is a top-level function for the system or organization. The top-level function is partitioned into a set of subfunctions that use the same inputs and produce the same outputs as the top-level function. Each of these subfunctions can then be partitioned further, with the decomposition process continuing as often as it is useful.

Second, functional analysis diagrams can represent the flow of data or items among the functions within any portion of the functional decomposition. As the first and subsequent functional decompositions are examined, it is common for one function to produce outputs that are not useful outside the boundaries of the system or organizations. These outputs are needed by other functions in order to produce the needed and expected external outputs.

Processing instructions are a third element that appear in some functional analysis diagrams. These instructions contain the needed information for the functions to transform the inputs to the outputs.

The fourth element is the control flow that sequences the termination and activation of the functions so that the process is both efficient and effective.

Feedback and control

Feedback plays an important role in functional analysis and modeling. Feedback and control is the comparison of the actual characteristics of an output with desired characteristics of that output for the purpose of adjusting the process of transforming inputs into that output. Open-loop control processes may or may not make this measurement, but in either case make no adjustments to the process once started. Closed-loop control processes use measurements of the output as feedback for the purpose of adjusting or controlling the transformation process.

Mentioned in	?		Encyclopedia browser	?		Full browser	?
No references found			Funchal Function function application function call function code function complete function failure safety Function Generator Function Graph Language function hole function inlining function key function library function multiplier function overloading Function Point Analysis function prototype Function Space function switch function table function unit Function, Set function-evaluation routine Functional Functional Analysis Functional analysis and modeling functional analysis diagram functional anatomy functional application functional bombing functional constraint functional database functional decomposition functional dependency functional design Functional Determinant functional diagram functional disorder functional electrical stimulation Functional Electronics Functional Equation functional error recovery functional failure functional forms analysis chart functional generator functional group functional interleaving functional language functional multiplier functional paralysis functional program			Functional Activity Program Functional Activity Program Manager Functional Adaptation Skills Training Functional Address Symbol functional adequacy Functional Administrator Functional Adult Literacy Functional Adult Literacy Programme Functional Aerobic Impairment Functional Aerobic Impairment Functional Aerobic Impairment Functional Aerobic Impairment Functional Aerobic Impairment functional age Functional Agility and Speed Training Functional Agricultural Thesaurus Functional Airspace Block Functional Airspace Block Approach Functional alcoholic Functional alcoholic Functional alcoholic Functional algebra Functional Allocation functional alveolar emphysema functional alveolar emphysema functional alveolar emphysema functional alveolar emphysema Functional analysis Functional analysis Functional analysis Functional analysis and modeling Functional Analysis By Association Functional Analysis Concept Development functional analysis diagram Functional Analysis of Cancer Therapy Functional Analysis of Separated Allele in Yeast Functional Analysis Review Functional Analysis Screening Tool Functional Analysis Workbook Functional Analysis/Allocation Functional analyst Functional Analytic Causal Model functional anatomy functional anatomy functional anatomy Functional Anatomy and Pathophysiology Functional and Declarative Programming in Education Functional and Health Status Questionnaire Functional and Object Oriented Methodology Functional and Operational Requirements Functional and Performance Requirements Functional and Performance Requirements Document Functional and Technical Program functional antagonism functional application Functional Architecture Study Functional Area