2.2-Relevance and benefits of systems engineering Flashcards
Applicability
ANSI/EIA-632 states that the standard itself is intended to be appliable to ‘the engineering or the reengineering of: a) commercial or non-commercial systems, or part thereof; b) any system, small or large, simple or complex, software-intensive or not, precedented or unprecedented; c) systems containing products made up of hardware, software, firmware, personnel, facilities, data, materials, services, techniques, or processes (or combinations thereof); d) a new system or a legacy system, or portions thereof.’
Systems engineering must be applied in a thoughtful manner
It is critical, therefore, that we understand the merits of systems engineering and apply them in a tailored manner, cognizant of the relative size, complexity, and risks associated with each system development.
Use of system engineering
Systems engineering is relevant to both customers and suppliers: -Customers use systems engineering to define business, stakeholder and system requirements, as well as to monitor contractor progress and risk. -Contractors use systems engineering to develop effective processes for the design, development and test of systems. -Both parties are looking to produce “quality” systems whilst minimizing exposure to risk.
Benefits
1-Savings in life-cycle costs 2-Reduction in the overall acquisition schedule 3-Reduction in technical risk 4-And a quality system
LCC savings
While some may argue that the additional requirements imposed by systems engineering can increase costs, these increases are comparatively small and are generally felt in the very early design phases. Experience indicates that an early emphasis on systems engineering can result in significant cost savings later in the construction and/or production, operational use and system support, and disposal phases of the life cycle. The figure here provides a simplistic illustration of the impact of systems engineering on the system life cycle. This curve shows that systems engineering has its greatest impact through the rigorous application of processes and methodologies during the early stages of the project where the ease of change and cost of modification is the lowest. In fact, the curve in the figure has been labelled as the ease with which changes can be made throughout the system life cycle. Additionally, as illustrated in the second curve in the figure, the greatest impact of requirements engineering comes at a time when the cost of implementing changes is the lowest. That is, the earlier we detect and correct errors, the easier they are to correct. Consequently, systems engineering provides the ideal opportunity to have the greatest impact on a project at a time when changes are easiest and least expensive to make.
Reduction acquisition time
A reduction in overall acquisition time is possible through solid requirements engineering efforts. By getting the requirements right early and then monitor their inclusion into the subsequent design, we can reduce the potential for costly and time consuming changes later. System failures, cost overruns, and schedule problems are often the direct result of poor requirements-engineering practices— poor requirements cannot be rectified by good design.
Reduction in Technical Risk
Systems engineering leads to a reduction in the technical risks associated with the development of the system. 1-Risks are identified early and monitored throughout the lifecycle. Even early on in the process, a focus on feasibility analysis reduces subsequent risk to the project. 2-Through systems engineering, design decisions can be traced back to the original user requirements and conflicting user requirements can be identified and clarified early, significantly reducing the risk of failure later in the project. 3-Technical risk is monitored and assessed continuously through a system of technical performance measures, and design reviews and audits.
Quality system
Finally, and probably most importantly, the disciplined approach to systems engineering leads to a product that meets the original intended purpose more completely. we use the word quality to refer to fitness-for purpose, Requirement focus and their traceability into design, SE helps to ensure: -specified requirements reflect the business and stakeholder needs -resulting system meets the specified requirements
System engineering framework
three main elements of systems engineering: 1-Processes - the “doing” element 2-Management - the “controlling” element 3-Tools - assisting both management and processes 4-These elements are placed within the context of a fourth element called related disciplines This course emphasis on Acquisition phase in which SE has the most impact on a system.
System Engineering processes
Systems engineering processes and tasks are divided into the life-cycle stages within which they typically occur. All extant systems engineering standards and practices extol processes that are built around an iterative application of analysis, synthesis, and evaluation.
System Engineering Management
Systems engineering management is an overarching activity responsible for directing the systems engineering effort, monitoring and reporting that effort to the appropriate areas, and reviewing and auditing it at critical stages in the entire process. Major systems engineering management elements are: 1) technical reviews and audits, 2) system test and evaluation, 3) technical risk management, 4) configuration management, 5) enforce use of specifications and standards, 6) integration management, and 7) management planning. The pre-eminent position of systems engineering management in the framework illustrates that it is the key to the entire systems engineering effort.
System Engineering Tools
These tools range from techniques and methods through to systems engineering standards. Most popular information systems or standards here. Processes tools cover requirement management, assorted analysis, synthesis and evaluation processes. We present generic process tools such as: 1) requirements breakdown structures (RBS), 2) functional flow block diagrams (FFBD), 3) work breakdown structures (WBS), 4) trade-off analyses, and 5) prototyping and simulation Also capability maturity models.
Related disciplines
Examples include: 1) project management, 2) logistics management, 3) quality assurance, 4) requirements engineering, 5) hardware engineering, 6) software engineering. The relationship between the related disciplines and the other facets of systems engineering depends very much upon the discipline in question. Some (such as project management) oversee the whole systems engineering discipline, while others (such as hardware and software engineering) sit between systems engineering management and the processes, and others (such as quality assurance) sit alongside the systems engineering effort.
Foundation processes
Obviously are analysis, synthesis and evaluation. The iterative nature of the application is critical to systems engineering processes. Initially the process is applied at the systems level; it is then re-applied at the subsystem level, and then the assembly level, and so on until the entire development process is complete. This concept is not complex; it is simply a good, sound approach to problem solving that is applicable in any domain but is particularly fundamental to systems engineering.
Analysis
During Conceptual Design, analysis investigates the business and stakeholder needs and identifies the essential requirements of the system in order to meet the needs. Analysis at the system level aims to answers the what, how well, and the why questions relative to the system design. Analysis activities continue throughout the subsequent stages of the life cycle to help in defining the lower-level requirements associated with physical aspects (the hows) of the system design. Depending on the particular design phase, these requirements may be grouped in accordance with some logical criteria and then allocated to a particular physical component of the system. That is, the component becomes responsible for the satisfaction of those requirements by performing the functions assigned to it. The allocation of requirements forms a description of the system elements and architecture and therefore assists in the process of synthesis or design (answering the how questions).
Evaluation
Evaluation is the process of investigating the trade-offs between requirements and design, considering the design alternatives, and making the necessary decisions. The process of evaluation continues throughout all stages of the systems engineering effort, ultimately determining whether the system satisfies the original requirements. Trade-off analysis is one of the tools available to the system designer in performing evaluation of competing requirements or designs. The outcome of the evaluation is a selection or confirmation of the desired approach to design. Discrepancies are also identified if applicable and may result in further analysis and synthesis as the analysis-synthesis-evaluation loop is closed.
