5.2.4 Frat – A Basic Framework for Systems Engineering

Abstract

Systems engineering can be difficult to implement if the words and framework are not clearly understood by all parties involved. INCOSE has adopted a definition of systems engineering; yet a debate continues over what systems engineering is and how to do it. The authors have developed over a period of many years the FRAT framework for describing the process used to implement systems engineering for any task, the name for which is derived by the first letters of the series of words function, requirement, answer, and test. FRAT is based on the hypothesis that four views of a system are needed to completely define any system. These views are what it does (functions), how well the functions are performed (requirements), a physical or actual description of the system (answers), and verification and validation of the system when completed (tests). The FRAT framework has been validated by reviewing all the papers published at INCOSE proceedings. It is important to recognize that the system of interest (a product) is produced by another system (a production system). Both of these systems can be described by the four FRAT views when developing a shared vision of the development process as well as the product that is developed.

1.3.2 A Generic, Adaptive Systems Engineering Information Model

“…(Grady 1995) The key area of confusion, according to Grady, is the relationship between the current level of system definition activity and the higher-level system need or function that produced the lower-level system requirements activity. This fundamental semantic relationship between the specified need and the specified solution, as it appears in the program lifecycle, has been documented by the following authors: Forsberg and Mooz (1991), Mar and Morais (2002), and Simpson and Simpson (2001).…”

Assessing Po River Deltaic Vulnerability Using Earth Observation and a Bayesian Belief Network Model

“…Twelve variables are identified as relevant for simulating deltaic vulnerability scenarios, bearing in mind that delta systems are rapidly developing areas with changing landforms, sediment deposition rates, and vegetation cover. The physical, ecological, and social variables have been grouped in three broad classes representing the sources (driver factors-DFs), the pathway (land cover factors-LCFs), and the receptors (land use factors-LUFs) of the vulnerability [78,79] (respectively colored in red, green, and blue in Table 1).…”

“…Bayesian belief network (BBN) conceptual model and associated source-pathway-receptorconsequence (SPRC_chain applied to the vulnerability assessment[78,79]. BBN conceptual model…”

A systems framework for distance learning in engineering graduate programs

“…Good examples of systems structures are available in Sage and Rouse [2009] and Blanchard and Fabrycky [2011]. Mar and Morais [2002] present the FRAT (Function, Requirement, Answer, and Test) structure as a basic framework for systems engineering. Although a number of such structures are available in the literature, the fact remains that each application scenario will need to customize a generic model to fit the specific needs of the prevailing application.…”