Functional Requirements
In software engineering and systems engineering, a functional requirement defines a function of a system or its component, where a function is described as a specification of behavior between inputs and outputs. Functional requirements may involve calculations, technical details, data manipulation and processing, and other specific functionality that define what a system is supposed to accomplish. Behavioral requirements describe all the cases where the system uses the functional requirements, these are captured in use cases. Functional requirements are supported by non-functional requirements (also known as "quality requirements"), which impose constraints on the design or implementation (such as performance requirements, security, or reliability). Generally, functional requirements are expressed in the form "system must do ," while non-functional requirements take the form "system shall be ." The plan for implementing functional requirements is detailed in the system design, whe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Software Engineering
Software engineering is a systematic engineering approach to software development. A software engineer is a person who applies the principles of software engineering to design, develop, maintain, test, and evaluate computer software. The term '' programmer'' is sometimes used as a synonym, but may also lack connotations of engineering education or skills. Engineering techniques are used to inform the software development process which involves the definition, implementation, assessment, measurement, management, change, and improvement of the software life cycle process itself. It heavily uses software configuration management which is about systematically controlling changes to the configuration, and maintaining the integrity and traceability of the configuration and code throughout the system life cycle. Modern processes use software versioning. History Beginning in the 1960s, software engineering was seen as its own type of engineering. Additionally, the development of soft ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Function (engineering)
In engineering, a function is interpreted as a specific process, action or task that a system is able to perform.R.Barker, C. Longman, Case Method: Function and Process Modelling, Addison-Wesley Professional, 1992. In engineering design In the lifecycle of engineering projects, there are usually distinguished subsequently: '' Requirements'' and ''Functional specification'' documents. The ''Requirements'' usually specifies the most important attributes of the requested system. In the ''Design specification'' documents, physical or software processes and systems are frequently the requested functions In products For advertising and marketing of technical products, the number of functions they can perform is often counted and used for promotion. For example a calculator capable of the basic mathematical operations of addition, subtraction, multiplication, and division, would be called a "four-function" model; when other operations are added, for example for scientific, financial, or ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Software Sizing
Software sizing or Software size estimation is an activity in software engineering that is used to determine or estimate the size of a software application or component in order to be able to implement other software project management activities (such as estimating or tracking). Size is an inherent characteristic of a piece of software just like weight is an inherent characteristic of a tangible material. Background Software sizing is different from software effort estimation. Sizing estimates the probable size of a piece of software while effort estimation predicts the effort needed to build it. The relationship between the size of software and the effort required to produce it is called productivity. For example, if a software engineer has built a small web-based calculator application, we can say that the project effort was 280 man-hours. However, this does not give any information about the size of the ''software product'' itself. Conversely, we can say that the application s ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Separation Of Concerns
In computer science, separation of concerns is a design principle for separating a computer program into distinct sections. Each section addresses a separate '' concern'', a set of information that affects the code of a computer program. A concern can be as general as "the details of the hardware for an application", or as specific as "the name of which class to instantiate". A program that embodies SoC well is called a modular program. Modularity, and hence separation of concerns, is achieved by encapsulating information inside a section of code that has a well-defined interface. Encapsulation is a means of information hiding. Layered designs in information systems are another embodiment of separation of concerns (e.g., presentation layer, business logic layer, data access layer, persistence layer). Separation of concerns results in more degrees of freedom for some aspect of the program's design, deployment, or usage. Common among these is increased freedom for simplification and ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Functional Model
In systems engineering, software engineering, and computer science, a function model or functional model is a structured representation of the functions ( activities, actions, processes, operations) within the modeled system or subject area.FIPS Publication 183 released of IDEFĂ December 1993 by the Computer Systems Laboratory of the National Institute of Standards and Technology (NIST). ![]() [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Functional Design
Functional Design is a paradigm used to simplify the design of hardware and software devices such as computer software and, increasingly, 3D models. A functional design assures that each modular part of a device has only one responsibility and performs that responsibility with the minimum of side effects on other parts. Functionally designed modules tend to have low coupling. Advantages The advantage for implementation is that if a software module has a single purpose, it will be simpler, and therefore easier and less expensive, to design and implement. Systems with functionally designed parts are easier to modify because each part does only what it claims to do. Since maintenance is more than 3/4 of a successful system's life, Software Maintenance Costs by Jussi Koskinen this feature is a crucial advantage. It also makes the system easier to understand and documen ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Functional Decomposition
In mathematics, functional decomposition is the process of resolving a functional relationship into its constituent parts in such a way that the original function can be reconstructed (i.e., recomposed) from those parts by function composition. This process of decomposition may be undertaken to gain insight into the identity of the constituent components which may reflect individual physical processes of interest. Also functional decomposition may result in a compressed representation of the global function, a task which is feasible only when the constituent processes possess a certain level of ''modularity'' (i.e., independence or non-interaction). between the components are critical to the function of the collection. All interactions may not be , but possibly deduced through repetitive , synthesis, validation and verification of composite behavior. Basic mathematical definition For a multivariate function y = f(x_1,x_2,\dots,x_n), functional decomposition generally refers ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Function (mathematics)
In mathematics, a function from a set to a set assigns to each element of exactly one element of .; the words map, mapping, transformation, correspondence, and operator are often used synonymously. The set is called the domain of the function and the set is called the codomain of the function.Codomain ''Encyclopedia of Mathematics'Codomain. ''Encyclopedia of Mathematics''/ref> The earliest known approach to the notion of function can be traced back to works of Persian mathematicians Al-Biruni and Sharaf al-Din al-Tusi. Functions were originally the idealization of how a varying quantity depends on another quantity. For example, the position of a planet is a ''function'' of time. Historically, the concept was elaborated with the infinitesimal calculus at the end of the 17th century, and, until the 19th century, the functions that were considered were differentiable (that is, they had a high degree of regularity). The concept of a function was formalized at the end of the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Function (computer Science)
In computer programming, a function or subroutine is a sequence of program instructions that performs a specific task, packaged as a unit. This unit can then be used in programs wherever that particular task should be performed. Functions may be defined within programs, or separately in libraries that can be used by many programs. In different programming languages, a function may be called a routine, subprogram, subroutine, method, or procedure. Technically, these terms all have different definitions, and the nomenclature varies from language to language. The generic umbrella term ''callable unit'' is sometimes used. A function is often coded so that it can be started several times and from several places during one execution of the program, including from other functions, and then branch back (''return'') to the next instruction after the ''call'', once the function's task is done. The idea of a subroutine was initially conceived by John Mauchly during his work on ENIAC, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Systems Engineering
Systems engineering is an interdisciplinary field of engineering and engineering management that focuses on how to design, integrate, and manage complex systems over their enterprise life cycle, life cycles. At its core, systems engineering utilizes systems thinking principles to organize this body of knowledge. The individual outcome of such efforts, an engineered system, can be defined as a combination of components that work in synergy to collectively perform a useful Function (engineering), function. Issues such as requirements engineering, reliability, logistics, coordination of different teams, testing and evaluation, maintainability and many other Discipline (academia), disciplines necessary for successful system design, development, implementation, and ultimate decommission become more difficult when dealing with large or complex projects. Systems engineering deals with work-processes, optimization methods, and risk management tools in such projects. It overlaps technical ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Project Stakeholder
Project stakeholders are persons or entities who have an interest in a given project. According to the Project Management Institute (PMI), the term ''project stakeholder'' refers to "an individual, group, or organization, who may affect, be affected by, or perceive itself to be affected by a decision, activity, or outcome of a project". ISO 21500 uses a similar definition. Stakeholders may be located inside or outside an organization, including: # the project's sponsor; # those with an interest or the potential to gain from the successful completion of a project; #anyone who may have a positive or negative influence in the project completion. Example roles The following are examples of project stakeholders: * Project leader * Senior management * Project team members * Project customer * Resource managers * Line managers * Product user group * Project testers * Any group impacted by the project as it progresses * Any group impacted by the project when it is completed * Subcontract ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |