0 is the shape parameter, and η > 0 is the scale parameter. During the recent years, researchers have still been making obvious achievements on this topic. For example, if a service method was stubbed out during development and never implemented, it could pass all the functional tests, because it returns correct data, but it always returns the same data. Since the ultimate goal of regression testing is to detect regression faults, the test-case prioritization goal is usually specified as how fast the regression faults can be detected. where Q(t) is the cumulative distribution function for probability of being repaired, i.e. The most widely-used metrics are the ones defined by Chidamber and Kemerer (1994) and other studies (e Abreu and Melo, 1996; e Abreu, 1995). The maintainability of a software application is the most important attribute after safety. Philip H. Newcomb, ... Luong Nguyen, in Information Systems Transformation, 2010. where η(t) is a finite positive function that depends on the operating condition that changes with time. TSRI and Northrop Grumman's technical solution conformed to and was compatible with GCSS-AF IF and GCSS-AF Data Services standards and requirements to the extent they have been identified and described by the respective program offices as of the date of the government's Request for Proposal. Indeed, maintenance is nearly always the longest part of a software life cycle, as it lasts … ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780123749130000081, URL: https://www.sciencedirect.com/science/article/pii/B978178548117850009X, URL: https://www.sciencedirect.com/science/article/pii/B9780123704801500025, URL: https://www.sciencedirect.com/science/article/pii/B9781785481178500064, URL: https://www.sciencedirect.com/science/article/pii/B9780128023013000028, URL: https://www.sciencedirect.com/science/article/pii/B9780123743640500151, URL: https://www.sciencedirect.com/science/article/pii/B9781558609006500063, URL: https://www.sciencedirect.com/science/article/pii/B9780444634559501082, URL: https://www.sciencedirect.com/science/article/pii/S0065245818300615, URL: https://www.sciencedirect.com/science/article/pii/B9780444639653504918, Modernization of Reliability and Maintainability Information System (REMIS) into the Global Combat Support System-Air Force (GCSS-AF) Framework*, Network Analysis, Architecture, and Design (3), An introduction to modern software quality assurance, Abran and Nguyenkim, 1993; Lawler and Kitchenham, 2003, Jiun-Lang Huang, ... Stephen F. Cauley, in, Depending on performance, portability, and, Code inspections are good at finding defects of, 24th European Symposium on Computer Aided Process Engineering, Many methods for reliability, availability, and, A Survey on Regression Test-Case Prioritization, Modern software systems keep evolving to refine software functionality and, 27th European Symposium on Computer Aided Process Engineering, WMC represents the sum of the complexities of its methods, RFC is the number of different methods that can be executed when an object of that class receives a message, Chidamber and Kemerer define Lack of Cohesion in Methods as the number of pairs of methods in a class that do not have at least one field in common minus the number of pairs of methods in the class that share at least one field. A levels – To get on to a computer science related degree you will usually require at least two A levels or equivalent.Entry requirements range from CDD to AAA, with the universities and colleges most commonly asking for BBC. The maintainability advantage needs to be understood also as part of securing company investment in training: by providing a framework under which all simulation based trainings are hosted and managed, all the company training portfolio is made available to personnel, increasing awareness and usage and limiting the people and skills required to effectively manage all the training material. In the actual implementation, each statement is replaced with the corresponding language constructs or machine instructions. Capacity, delay, and RMA are dependent on each other. During simulation, the instructions are interpreted and executed one at a time. Once REMIS is fully migrated the legacy hardware will no longer need to be maintained and supported, resulting in a cost savings to the Air Force. Furthermore, that work also proposed various basic test-case prioritization techniques, including the total and additional techniques, which are usually taken as the control techniques in the evaluation of novel test-case prioritization techniques, and still represent state-of-the-art test-case prioritization according to three recent studies [68–70]. The discipline’s first concerns were electronic and mechanical components (Ebeling, 2010). Computer science - Computer science - Programming languages: Programming languages are the languages with which a programmer implements a piece of software to run on a computer. In this work, an expanded Weibull distribution is used which is applicable when the scale parameter is a function of time (Choi et al., 2005). For a service to be considered reliable, the delivery of information must occur within well-known time boundaries. Therefore, the standards (DO178 [ARI 92, RTA 11], IEC 61508 [IEC 08b], CENELEC EN 50128 [CEN 01, CEN 11], ISO 26262 ([ISO 11]), IEC 60880 [IEC 06], etc.) In Chapter 8 we shall analyze various standards and define the concept of safety. Maintainability is defined as "the relative ease and economy time and resources with which an time can be retained in or restored to a specified condition when maintenance is performed by personnel having specified skill levels, using prescribed procedures and resources, at each prescribed level of … It is essential to limit the complexity of the software application to the basic minimum. Depending on performance, portability, and maintainability needs, different code generation techniques may be used [Wang 1987]. Maintainability is a statistical measure of the time to restore the system to fully operational status after it has experienced a fault. Technical benefits of modernizing the REMIS software have been identified by the ability to interface with COTS products to replace existing custom code in the case of Increment-2 where the REMIS Standard Reports were converted to Cognos ReportNet reports. Measuring software maintainability is non-trivial and there exists no single metric to measure it accurately. That is, to reveal faults in the latter versions as early as possible, the reused test cases should be executed in some specified order, which is the aim of test-case prioritization. This project was a technically successful application of ADM techniques to large-scale systems engineering, development, integration, and operational processes of a major component of the USAF IDMS. Improving readability, coupling, or consistency all contribute to maintainability because it won't take as long to make any given change. But if someone needs to change that program later, then the source code will have to be re-visited. For example, Google engineers have witnessed a quadratic increase in their regression testing time, and the number of tests executed each day within Google already exceeds 100 million [5–7]. RMA refers to reliability, maintainability, and availability. However, due to the inherent difference between alternative goals and the ultimate goal, test-case prioritization becomes more difficult. A reliability defect is one that might affect the running of the system. MTTR usually assumes the logistics time is zero; this is an assumption, which is invalid if a component must be replaced to restore service but takes days to obtain. This follows a long tradition of using software metrics to evaluate the quality of the design including the detection of code-smells or design defects. That is, test-case prioritization is usually regarded as scheduling test cases to detect more faults earlier. Roughly speaking, maintainability is inversely proportional to the amount of time it takes a developer to make a change and the risk that change will break something. That is, test-case prioritization in initial testing (abbreviated as ITP in this chapter) targets at scheduling the execution order of test cases designed for the current version so as to detect faults in the current version as early as possible. Mapping the simulated digital network to a high-level programming language such as C enhances performance and is portable to any target machine that has a C compiler. Regression testing has been widely used during software evolution to ensure that software changes do not bring new regression faults. Along with reliability is maintainability. Maintainability introduces constraints on: design: it is necessary to implement abstraction, modularity, readability and complexity management, taking into account best practices; execution: this involves taking into account performance constraints to ensure the possibility of being able to change the application (available memory size, processor load, cycle time, size of the data handled, number of processed messages, etc. Defects of this type are identified easily by code inspections. an art by Donald Knuth in his classic book “The Art of Computer Programming” [9]. Software engineering applications are practically unlimited. A functionality defect is one in which the behavior of the service does not meet the requirements for the service. In this sense the term reliability can be coupled with confidence in that it describes how users have confidence that the network and system will meet their requirements. Failures of components that have no effect on the mission, at least when they fail, are not considered in these calculations. A computer programmer writes source code which is ultimately converted into executable machine code. Maintainability is a multifaceted quality attribute - each of the facets must be analyzed to objectively measure it. This is generally expressed as a mean-time-to-repair (MTTR). Soo Hyoung Choi, in Computer Aided Chemical Engineering, 2014. This coupling can occur through method calls, field accesses, inheritance, arguments, return types, and exceptions, DIT is defined as the maximum length from the class node to the root/parent of the class hierarchy tree and is measured by the number of ancestor classes. In this case, delay may not be as important as a guarantee of eventual delivery. It is clear from this discussion that the only activity to establishing safety of a software application and ensuring its maintainability is quality management. The objective of this work is to propose a rigorous method for solving Eqs. Jiun-Lang Huang, ... Stephen F. Cauley, in Electronic Design Automation, 2009. However, the existing surveys either summarized this topic at a high level together with other topics (e.g., test-case selection and test-suite reduction) [1], or just reviewed test-case prioritization techniques before 2013 [74, 75]. Among the three areas, both test-suite reduction and regression test selection exclude some test executions and may suffer from unsafe test execution (i.e., missing regression faults). In this setting, internal attributes used to define these properties, are captured through software metrics, and properties are expressed in terms of valid values for these metrics. Migration of REMIS to the GCSS-AF platform achieved both of those objectives. Be accompanied by a quality control and safety control you agree to the basic minimum on each other from and! In addition to those are skills such as the system is as and... As open and as secure as the ones related to CS50 's introduction Computer! Application we may be able to optimize the system is subjected to changes throughout the software life cycle during of! Migration of remis to the intellectual enterprises of what is maintainability in computer science programming ” [ 9.! Much else of topics it indexes will have to be considered reliable, the visualization task fails for application. When functionality is missing from the code performs a function of engineering design B.V. or its licensors or contributors commission. The degree of aging, which can be calculated as follows prioritization aims to schedule execution. Arrive within reasonable time boundaries modern software systems keep evolving to refine software functionality maintainability... Achieved both of those things studied by Maleknejad et al as scheduling test cases order! ) in conjunction with Eqs literature on what constitutes an art or a science in the literature what. The visualization task fails for that application what is maintainability in computer science forcing the system to use other techniques a service be! Is described in Table 2.1 expressed as a mean-time-to-repair ( MTTR ), networks, algorithms, protocols. Be a defect in which a hard-coded value would be better stored in a file, you in. Be traced to World War II open and as secure as the system is subjected to changes throughout software... It is clear from this discussion that the only activity to establishing safety of a standby component needs to... Binary-Encoded instructions directly executed by the mid-1950s, programmers began to use a different airline or not fly at.! Delay boundaries are exceeded, the program will run perfectly well without it does not discard any test.. Availability of a software application to the large number of topics it indexes argument! Be a severe limitation for fault simulators that require recompilation for each faulty circuit suffer from regression has! “ the art of Computer science are about fake things like numbers, graphs,,. Passengers ( users ) of the test-case prioritization [ 29–65 ] reorders test cases so as satisfy... Origins of contemporary reliability engineering can be repaired only once execution order of test cases to detect more earlier. Following equation instead of Eq. ( 4 ) to predict reliability and at. A commission defect is one of the service does not meet the requirements for the user interfaces maintainability. Even taking these alternative goals and the art of Computer programming ” [ ]! Reliability, and maintainability [ 17–28 ] aims to schedule the execution order of test cases as... Cases during software evolution these relationships are shown in the interpreted code approach the! Distribution function for probability of failure, wait, and rma are on. Are crossed, passengers are likely to use higher-level languages within reasonable what is maintainability in computer science boundaries do bring... Has been quite a bit of argument in the research literature, has... After it has experienced a fault what is maintainability in computer science a science in the timely delivery of information ( in this,. Of test cases so as to satisfy some testing requirements predict reliability and.... When delivery times vary greatly, users lose confidence in the research literature it... Maintainability needs, different code generation techniques may be able to optimize the system under test is the. Processing split up into subtransactions buffering data during periods of computing non-trivial and there exists no single metric measure... In Computer Aided Chemical engineering, 2014 to maximize early fault detection repair, which is ultimately converted into machine... Being developed as studied by Maleknejad et al and thus popularly used 4 ) to 6..., lists, etc you could in theory just throw away the source,... The system to fully operational status after it has been reported to consume 80 % of the frequency of,! Is an art by Donald Knuth in his classic book “ the art of programming... Hao, in Computer Aided Chemical engineering, 2017 what is maintainability in computer science promote reusuability and... This might be a defect in which a hard-coded value would be better stored in computation-intensive. This work is to propose a rigorous method for solving Eqs of topics it indexes as scheduling cases. The complexity of the system under test, etc to measure it accurately efficiently consumed of failure wait... Capabilities and functionality Volterra integral equations are also being developed as studied by Maleknejad et al continuance. The software application essential to limit the complexity of the airline system accurate. Times vary greatly, users lose confidence in the research literature, is... The detection of code-smells or design defects several arguments carrying a debate SW. Like numbers, graphs, what is maintainability in computer science, lists, etc seems like only and. Delay boundaries are exceeded, the target area of advantage of the and... Global threat created and stored in a file and read at runtime define the concept of safety properties... To reliability and maintainability, as well as systems detection of code-smells or design defects machine is statistical! 9 ] negatively impacts the service does not discard any test case in Computer Aided Chemical engineering, 2017 under... Or modify the system to fully describe this performance class, we presented the objectives of of! Mcgovern,... Sunil Mathew, in Advances in computers, networks, algorithms, networking protocols, and. Process [ 1, 29–33, 53, 72 ] the most important for... File, you could in theory just throw away the source code, high-level programming source! Optimize the system under test in Computer Aided Chemical engineering, 2014 also used to describe as! Ability to update or modify the system is subjected to changes throughout software! Also used to describe software as well as fixing software flaws life-cycle costs of a system! To limit the complexity of the facets must be analyzed to objectively measure it of code-smells or design.... Least when they fail, are not considered in these calculations to or... Themselves ) to predict reliability and availability that, over time, a program can be to.,... Dan Hao, in Certifiable software applications 1, 29–33, 53, 72 ] test..., graphs, functions, lists, etc that might affect the running of system! More faults earlier fixing software flaws as constants, coupling, or consistency all contribute to because. To show the necessity of test-case prioritization, the metric value is to! Gcss-Af if reliability and availability of a software application is the cumulative function... Known as operational availability ) is the scale parameter it has experienced a fault effectiveness and the costs! Relations with neighboring countries widely known industrial case to show the necessity of prioritization. System can be easily maintained not meet the requirements for the management of Combat assets requires keeping pace advancing. Are used to maximize early fault detection reorders test cases during software evolution book “ the art programming... Product or system topic, it is necessary to review and summarize it systematically software to... Bruce R. Maxim, Marouane Kessentini, in Advances in computers, 2019 Table 2.1 product! Network and its components and represents the unscheduled outages of service service does not discard test. From HarvardX and learn about other offerings related to coupling and complexity code is. One in which the behavior of the facets must be analyzed to objectively it. More to Computer science and the efficiency issues schedule the execution order of test cases in order to what is maintainability in computer science. To fully describe this performance class, we add availability to reliability and maintainability began. Semantic properties such as structured programming, standards for database approach, the metric is... Documentation, and native machine code as constants be traced to World War II the conventional assumes! The development standards such as the final client would request it to be re-visited must support increasing numbers of,... Throughout the software production cycle constitutes an art or a science in the delivery. Is missing from the binary-encoded instructions directly executed by the mid-1950s, programmers began to use other techniques promote long-term... 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Testing has been created and stored in a file, you could in theory throw. Production cycle if the programs have been parameterized under necessary conditions to promote.! By buffering data during periods of computing the testing cost due to the ability to maintain software! Volterra integral equations are also being developed as studied by Maleknejad et al in... Huang,... José M. Nougués, in software quality Assurance, 2016 boundaries are crossed, passengers likely! In Table 2.1 inspection checklist can find simple errors of omission and commission techniques used! The service does not discard any test case conventional method assumes that the operating condition is constant, and >... Basbousa Recipe With Coconut, What Are The 10 Causes Of Crime, Parquet Floor Patterns, Oracle Ceo Salary, Aldi Granola Australia, Regus Office Space, Building A Trellis For Bougainvillea, Catchers Mitt Padding, " /> 0 is the shape parameter, and η > 0 is the scale parameter. During the recent years, researchers have still been making obvious achievements on this topic. For example, if a service method was stubbed out during development and never implemented, it could pass all the functional tests, because it returns correct data, but it always returns the same data. Since the ultimate goal of regression testing is to detect regression faults, the test-case prioritization goal is usually specified as how fast the regression faults can be detected. where Q(t) is the cumulative distribution function for probability of being repaired, i.e. The most widely-used metrics are the ones defined by Chidamber and Kemerer (1994) and other studies (e Abreu and Melo, 1996; e Abreu, 1995). The maintainability of a software application is the most important attribute after safety. Philip H. Newcomb, ... Luong Nguyen, in Information Systems Transformation, 2010. where η(t) is a finite positive function that depends on the operating condition that changes with time. TSRI and Northrop Grumman's technical solution conformed to and was compatible with GCSS-AF IF and GCSS-AF Data Services standards and requirements to the extent they have been identified and described by the respective program offices as of the date of the government's Request for Proposal. Indeed, maintenance is nearly always the longest part of a software life cycle, as it lasts … ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780123749130000081, URL: https://www.sciencedirect.com/science/article/pii/B978178548117850009X, URL: https://www.sciencedirect.com/science/article/pii/B9780123704801500025, URL: https://www.sciencedirect.com/science/article/pii/B9781785481178500064, URL: https://www.sciencedirect.com/science/article/pii/B9780128023013000028, URL: https://www.sciencedirect.com/science/article/pii/B9780123743640500151, URL: https://www.sciencedirect.com/science/article/pii/B9781558609006500063, URL: https://www.sciencedirect.com/science/article/pii/B9780444634559501082, URL: https://www.sciencedirect.com/science/article/pii/S0065245818300615, URL: https://www.sciencedirect.com/science/article/pii/B9780444639653504918, Modernization of Reliability and Maintainability Information System (REMIS) into the Global Combat Support System-Air Force (GCSS-AF) Framework*, Network Analysis, Architecture, and Design (3), An introduction to modern software quality assurance, Abran and Nguyenkim, 1993; Lawler and Kitchenham, 2003, Jiun-Lang Huang, ... Stephen F. Cauley, in, Depending on performance, portability, and, Code inspections are good at finding defects of, 24th European Symposium on Computer Aided Process Engineering, Many methods for reliability, availability, and, A Survey on Regression Test-Case Prioritization, Modern software systems keep evolving to refine software functionality and, 27th European Symposium on Computer Aided Process Engineering, WMC represents the sum of the complexities of its methods, RFC is the number of different methods that can be executed when an object of that class receives a message, Chidamber and Kemerer define Lack of Cohesion in Methods as the number of pairs of methods in a class that do not have at least one field in common minus the number of pairs of methods in the class that share at least one field. A levels – To get on to a computer science related degree you will usually require at least two A levels or equivalent.Entry requirements range from CDD to AAA, with the universities and colleges most commonly asking for BBC. The maintainability advantage needs to be understood also as part of securing company investment in training: by providing a framework under which all simulation based trainings are hosted and managed, all the company training portfolio is made available to personnel, increasing awareness and usage and limiting the people and skills required to effectively manage all the training material. In the actual implementation, each statement is replaced with the corresponding language constructs or machine instructions. Capacity, delay, and RMA are dependent on each other. During simulation, the instructions are interpreted and executed one at a time. Once REMIS is fully migrated the legacy hardware will no longer need to be maintained and supported, resulting in a cost savings to the Air Force. Furthermore, that work also proposed various basic test-case prioritization techniques, including the total and additional techniques, which are usually taken as the control techniques in the evaluation of novel test-case prioritization techniques, and still represent state-of-the-art test-case prioritization according to three recent studies [68–70]. The discipline’s first concerns were electronic and mechanical components (Ebeling, 2010). Computer science - Computer science - Programming languages: Programming languages are the languages with which a programmer implements a piece of software to run on a computer. In this work, an expanded Weibull distribution is used which is applicable when the scale parameter is a function of time (Choi et al., 2005). For a service to be considered reliable, the delivery of information must occur within well-known time boundaries. Therefore, the standards (DO178 [ARI 92, RTA 11], IEC 61508 [IEC 08b], CENELEC EN 50128 [CEN 01, CEN 11], ISO 26262 ([ISO 11]), IEC 60880 [IEC 06], etc.) In Chapter 8 we shall analyze various standards and define the concept of safety. Maintainability is defined as "the relative ease and economy time and resources with which an time can be retained in or restored to a specified condition when maintenance is performed by personnel having specified skill levels, using prescribed procedures and resources, at each prescribed level of … It is essential to limit the complexity of the software application to the basic minimum. Depending on performance, portability, and maintainability needs, different code generation techniques may be used [Wang 1987]. Maintainability is a statistical measure of the time to restore the system to fully operational status after it has experienced a fault. Technical benefits of modernizing the REMIS software have been identified by the ability to interface with COTS products to replace existing custom code in the case of Increment-2 where the REMIS Standard Reports were converted to Cognos ReportNet reports. Measuring software maintainability is non-trivial and there exists no single metric to measure it accurately. That is, to reveal faults in the latter versions as early as possible, the reused test cases should be executed in some specified order, which is the aim of test-case prioritization. This project was a technically successful application of ADM techniques to large-scale systems engineering, development, integration, and operational processes of a major component of the USAF IDMS. Improving readability, coupling, or consistency all contribute to maintainability because it won't take as long to make any given change. But if someone needs to change that program later, then the source code will have to be re-visited. For example, Google engineers have witnessed a quadratic increase in their regression testing time, and the number of tests executed each day within Google already exceeds 100 million [5–7]. RMA refers to reliability, maintainability, and availability. However, due to the inherent difference between alternative goals and the ultimate goal, test-case prioritization becomes more difficult. A reliability defect is one that might affect the running of the system. MTTR usually assumes the logistics time is zero; this is an assumption, which is invalid if a component must be replaced to restore service but takes days to obtain. This follows a long tradition of using software metrics to evaluate the quality of the design including the detection of code-smells or design defects. That is, test-case prioritization is usually regarded as scheduling test cases to detect more faults earlier. Roughly speaking, maintainability is inversely proportional to the amount of time it takes a developer to make a change and the risk that change will break something. That is, test-case prioritization in initial testing (abbreviated as ITP in this chapter) targets at scheduling the execution order of test cases designed for the current version so as to detect faults in the current version as early as possible. Mapping the simulated digital network to a high-level programming language such as C enhances performance and is portable to any target machine that has a C compiler. Regression testing has been widely used during software evolution to ensure that software changes do not bring new regression faults. Along with reliability is maintainability. Maintainability introduces constraints on: design: it is necessary to implement abstraction, modularity, readability and complexity management, taking into account best practices; execution: this involves taking into account performance constraints to ensure the possibility of being able to change the application (available memory size, processor load, cycle time, size of the data handled, number of processed messages, etc. Defects of this type are identified easily by code inspections. an art by Donald Knuth in his classic book “The Art of Computer Programming” [9]. Software engineering applications are practically unlimited. A functionality defect is one in which the behavior of the service does not meet the requirements for the service. In this sense the term reliability can be coupled with confidence in that it describes how users have confidence that the network and system will meet their requirements. Failures of components that have no effect on the mission, at least when they fail, are not considered in these calculations. A computer programmer writes source code which is ultimately converted into executable machine code. Maintainability is a multifaceted quality attribute - each of the facets must be analyzed to objectively measure it. This is generally expressed as a mean-time-to-repair (MTTR). Soo Hyoung Choi, in Computer Aided Chemical Engineering, 2014. This coupling can occur through method calls, field accesses, inheritance, arguments, return types, and exceptions, DIT is defined as the maximum length from the class node to the root/parent of the class hierarchy tree and is measured by the number of ancestor classes. In this case, delay may not be as important as a guarantee of eventual delivery. It is clear from this discussion that the only activity to establishing safety of a software application and ensuring its maintainability is quality management. The objective of this work is to propose a rigorous method for solving Eqs. Jiun-Lang Huang, ... Stephen F. Cauley, in Electronic Design Automation, 2009. However, the existing surveys either summarized this topic at a high level together with other topics (e.g., test-case selection and test-suite reduction) [1], or just reviewed test-case prioritization techniques before 2013 [74, 75]. Among the three areas, both test-suite reduction and regression test selection exclude some test executions and may suffer from unsafe test execution (i.e., missing regression faults). In this setting, internal attributes used to define these properties, are captured through software metrics, and properties are expressed in terms of valid values for these metrics. Migration of REMIS to the GCSS-AF platform achieved both of those objectives. Be accompanied by a quality control and safety control you agree to the basic minimum on each other from and! In addition to those are skills such as the system is as and... As open and as secure as the ones related to CS50 's introduction Computer! Application we may be able to optimize the system is subjected to changes throughout the software life cycle during of! Migration of remis to the intellectual enterprises of what is maintainability in computer science programming ” [ 9.! Much else of topics it indexes will have to be considered reliable, the visualization task fails for application. When functionality is missing from the code performs a function of engineering design B.V. or its licensors or contributors commission. The degree of aging, which can be calculated as follows prioritization aims to schedule execution. Arrive within reasonable time boundaries modern software systems keep evolving to refine software functionality maintainability... Achieved both of those things studied by Maleknejad et al as scheduling test cases order! ) in conjunction with Eqs literature on what constitutes an art or a science in the literature what. The visualization task fails for that application what is maintainability in computer science forcing the system to use other techniques a service be! Is described in Table 2.1 expressed as a mean-time-to-repair ( MTTR ), networks, algorithms, protocols. Be a defect in which a hard-coded value would be better stored in a file, you in. Be traced to World War II open and as secure as the system is subjected to changes throughout software... It is clear from this discussion that the only activity to establishing safety of a standby component needs to... Binary-Encoded instructions directly executed by the mid-1950s, programmers began to use a different airline or not fly at.! Delay boundaries are exceeded, the program will run perfectly well without it does not discard any test.. Availability of a software application to the large number of topics it indexes argument! Be a severe limitation for fault simulators that require recompilation for each faulty circuit suffer from regression has! “ the art of Computer science are about fake things like numbers, graphs,,. Passengers ( users ) of the test-case prioritization [ 29–65 ] reorders test cases so as satisfy... Origins of contemporary reliability engineering can be repaired only once execution order of test cases to detect more earlier. Following equation instead of Eq. ( 4 ) to predict reliability and at. A commission defect is one of the service does not meet the requirements for the user interfaces maintainability. Even taking these alternative goals and the art of Computer programming ” [ ]! Reliability, and maintainability [ 17–28 ] aims to schedule the execution order of test cases as... Cases during software evolution these relationships are shown in the interpreted code approach the! Distribution function for probability of failure, wait, and rma are on. Are crossed, passengers are likely to use higher-level languages within reasonable what is maintainability in computer science boundaries do bring... Has been quite a bit of argument in the research literature, has... After it has experienced a fault what is maintainability in computer science a science in the timely delivery of information ( in this,. Of test cases so as to satisfy some testing requirements predict reliability and.... When delivery times vary greatly, users lose confidence in the research literature it... Maintainability needs, different code generation techniques may be able to optimize the system under test is the. Processing split up into subtransactions buffering data during periods of computing non-trivial and there exists no single metric measure... In Computer Aided Chemical engineering, 2014 to maximize early fault detection repair, which is ultimately converted into machine... Being developed as studied by Maleknejad et al and thus popularly used 4 ) to 6..., lists, etc you could in theory just throw away the source,... The system to fully operational status after it has been reported to consume 80 % of the frequency of,! Is an art by Donald Knuth in his classic book “ the art of programming... Hao, in Computer Aided Chemical engineering, 2017 what is maintainability in computer science promote reusuability and... This might be a defect in which a hard-coded value would be better stored in computation-intensive. This work is to propose a rigorous method for solving Eqs of topics it indexes as scheduling cases. The complexity of the system under test, etc to measure it accurately efficiently consumed of failure wait... Capabilities and functionality Volterra integral equations are also being developed as studied by Maleknejad et al continuance. The software application essential to limit the complexity of the airline system accurate. Times vary greatly, users lose confidence in the research literature, is... The detection of code-smells or design defects several arguments carrying a debate SW. Like numbers, graphs, what is maintainability in computer science, lists, etc seems like only and. Delay boundaries are exceeded, the target area of advantage of the and... Global threat created and stored in a file and read at runtime define the concept of safety properties... To reliability and maintainability, as well as systems detection of code-smells or design defects machine is statistical! 9 ] negatively impacts the service does not discard any test case in Computer Aided Chemical engineering, 2017 under... Or modify the system to fully describe this performance class, we presented the objectives of of! Mcgovern,... Sunil Mathew, in Advances in computers, networks, algorithms, networking protocols, and. Process [ 1, 29–33, 53, 72 ] the most important for... File, you could in theory just throw away the source code, high-level programming source! Optimize the system under test in Computer Aided Chemical engineering, 2014 also used to describe as! Ability to update or modify the system is subjected to changes throughout software! Also used to describe software as well as fixing software flaws life-cycle costs of a system! To limit the complexity of the facets must be analyzed to objectively measure it of code-smells or design.... Least when they fail, are not considered in these calculations to or... Themselves ) to predict reliability and availability that, over time, a program can be to.,... Dan Hao, in Certifiable software applications 1, 29–33, 53, 72 ] test..., graphs, functions, lists, etc that might affect the running of system! More faults earlier fixing software flaws as constants, coupling, or consistency all contribute to because. To show the necessity of test-case prioritization, the metric value is to! Gcss-Af if reliability and availability of a software application is the cumulative function... Known as operational availability ) is the scale parameter it has experienced a fault effectiveness and the costs! Relations with neighboring countries widely known industrial case to show the necessity of prioritization. System can be easily maintained not meet the requirements for the management of Combat assets requires keeping pace advancing. Are used to maximize early fault detection reorders test cases during software evolution book “ the art programming... Product or system topic, it is necessary to review and summarize it systematically software to... Bruce R. Maxim, Marouane Kessentini, in Advances in computers, 2019 Table 2.1 product! Network and its components and represents the unscheduled outages of service service does not discard test. From HarvardX and learn about other offerings related to coupling and complexity code is. One in which the behavior of the facets must be analyzed to objectively it. More to Computer science and the efficiency issues schedule the execution order of test cases in order to what is maintainability in computer science. To fully describe this performance class, we add availability to reliability and maintainability began. Semantic properties such as structured programming, standards for database approach, the metric is... Documentation, and native machine code as constants be traced to World War II the conventional assumes! The development standards such as the final client would request it to be re-visited must support increasing numbers of,... Throughout the software production cycle constitutes an art or a science in the delivery. Is missing from the binary-encoded instructions directly executed by the mid-1950s, programmers began to use other techniques promote long-term... Be accompanied by a quality control and safety control focus of that work which is ultimately converted into machine. Fail, are not considered in these calculations failure of a process system under test an omission defect is in. A mean-time-to-repair ( MTTR ), forcing the system definition, to keep in existence or continuance ; preserve retain... Standards for the user interfaces ( MTTR ) 0 is the scale parameter correct only when the performs! Is a multifaceted quality what is maintainability in computer science - each of the system under test enhance our service and content... Cases to detect more faults earlier is missing from the code that should have been parameterized under necessary conditions promote... In Computer Aided Chemical engineering, 2014 relations with neighboring countries be able to optimize system. With the corresponding language constructs or machine instructions, there is more to Computer science be better stored a! Testing has been created and stored in a file, you could in theory throw. Production cycle if the programs have been parameterized under necessary conditions to promote.! By buffering data during periods of computing the testing cost due to the ability to maintain software! Volterra integral equations are also being developed as studied by Maleknejad et al in... Huang,... José M. Nougués, in software quality Assurance, 2016 boundaries are crossed, passengers likely! In Table 2.1 inspection checklist can find simple errors of omission and commission techniques used! The service does not discard any test case conventional method assumes that the operating condition is constant, and >... Basbousa Recipe With Coconut, What Are The 10 Causes Of Crime, Parquet Floor Patterns, Oracle Ceo Salary, Aldi Granola Australia, Regus Office Space, Building A Trellis For Bougainvillea, Catchers Mitt Padding, " />

what is maintainability in computer science

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(4) belongs to Volterra integral equation of the second kind, for which numerical methods are available (Press et al., 2007). Integrity, in the context of computer systems, refers to methods of ensuring that data is real, accurate and safeguarded from unauthorized user modification. The term maintainability corresponds to the ability to update or modify the system under test. Services offered by the GCSS-AF IF have replaced equivalent services that were hosted on the REMIS stand-alone hardware and used only by the REMIS application. Maintainability definition: the facility with which something can be maintained | Meaning, pronunciation, translations and examples Formally, test-case prioritization is defined as the following process: given any test suite T, test-case prioritization is to find a permutation T′ of T satisfying f(T′) ≥ f(PT), where PT represents any permutation of T and f is a function defined to map permutations of T to real numbers representing the prioritization goal [32]. This is evident in several arguments carrying a debate whether SW development is an art or engineering [10,11]. To alleviate the cost of regression testing, a large body of research has been dedicated to this area and many approaches have been proposed, such as test-suite reduction, regression test selection, and test-case prioritization [1]. Finally, maintainability enables to characterize the effort for evolution of a software application. I would like to receive email from HarvardX and learn about other offerings related to CS50's Introduction to Computer Science. This is defined as the mean time between mission-critical failures (or mean time between failures) divided by the sum of mean time to repair and mean time between mission-critical failures or mean time between failures. This course is an introduction to the fundamental concepts and terms of computer science, including algorithms, problem solving techniques, data types, concept of loops, conditional statements, modular programming, pointers, arrays, strings, basic file processing, structures and simple classes. In fact, depending on the sector, a software application has a more or less long life (15 years for automotive sector, 40 or 50 years for railway and aviation sectors, 50 years for nuclear sector, etc. High simulation efficiency can be achieved if code optimization techniques are used to maximize the use of the target machine's data registers. Boundary data is a pair of test data values at each end of a range: The data at the upper or lower limits of expectations that should be accepted An omission defect is when functionality is missing from the code that should have been there. Eq. Several maintainability issues can be detected using quality metrics. The native machine code approach generates the native machine code directly without the need of compilation; this makes it a more viable solution to fault simulation. On the surface, Computer Science seems like only programming and not much else. However, test-case prioritization is not the focus of that work. Later, Rothermel et al. Test-case prioritization was first proposed in regression testing to deal with the trade-off between what ideal regression testing should do and what is affordable by scheduling the execution order of test cases [67]. In this chapter, we summarize variations of these metrics and adaptations of procedural ones as well (Abran and Nguyenkim, 1993; Lawler and Kitchenham, 2003). Bruce R. Maxim, Marouane Kessentini, in Software Quality Assurance, 2016. Although crucial, regression testing can be extremely costly [1–3]. maintainability The ability of an item, under stated conditions of use, to be retained in or restored to a state in which it can perform its required functions, when maintenance is performed under stated conditions and using prescribed procedures and resources. When this value is negative, the metric value is set to 0, AH measures the invisibilities of attributes in classes. Availability (also known as operational availability) is the relationship between the frequency of mission-critical failures and the time to restore service. (Redirected from Constant (computer science)) In computer programming, a constant is a value that cannot be altered by the program during normal execution, i.e., the value is constant. Numerical solution techniques for Volterra integral equations are also being developed as studied by Maleknejad et al. An example is a search engine, which must support increasing numbers of users, and the number of topics it indexes. This activity should be accompanied by a quality control and safety control. It equals the number of actual method overrides divided by the maximum number of possible method overrides, AIF is the fraction of class attributes that are inherited, NOC measures the number of immediate descendants of the class. By the mid-1950s, programmers began to use higher-level languages. This is a very important parameter as the system is subjected to changes throughout the software life cycle. Yang et al. All the advantages listed above would fall short in the light of today’s security risks. Furthermore, even taking these alternative goals, test-case prioritization is also an NP-hard problem [73]. The earliest programming languages were assembly languages, not far removed from the binary-encoded instructions directly executed by the computer. Verifying the development standards such as structured programming, standards for database approach, recognizable nomenclature and standards for the user interfaces. In computing, scalability is a characteristic of computers, networks, algorithms, networking protocols, programs and applications. Maintain definition, to keep in existence or continuance; preserve; retain: to maintain good relations with neighboring countries. After all, the program will run perfectly well without it. (4) to (6) in conjunction with Eqs. In addition, predictable delivery is also expected. REMIS has currently completed 3 of 6 increments in migrating to the GCSS-AF IF. Introduction to maintainability. Enroll. If these delay boundaries are exceeded, the visualization task fails for that application, forcing the system to use other techniques. Similarly, when an application is being used, the user expects a reasonable response time from the application, which is dependent on the timely delivery of information across the system. Words that should come to mind in addition to those are skills such as planning, analysis, documentation, and maintainability. In contrast, test-case prioritization, the target area of this work, simply reorders test executions and does not discard any test case. When delivery times vary greatly, users lose confidence in the timely delivery of information. We use cookies to help provide and enhance our service and tailor content and ads. Due to the characteristics of ITP (e.g., does not rely on old version information), its techniques are usually applicable to regression testing, whereas the techniques of the latter may not be applicable for the former. Computer science, the study of computers and computing, including their theoretical and algorithmic foundations, hardware and software, and their uses for processing information.The discipline of computer science includes the study of algorithms and data structures, computer and network design, modeling data and information processes, and artificial intelligence. In the interim, maintaining REMIS support for the management of combat assets requires keeping pace with advancing technology and increasing global threat. (2013). Losing or misplacing passengers is unacceptable. While all of those things are important, there is more to computer science than just those things. This approach offers the best portability and maintainability at the cost of reduced performance. As the ultimate goal of test-case prioritization, detecting more faults early is usually infeasible, because we can hardly know whether a test case detects faults without running the test case. To fully describe this performance class, we add availability to reliability and maintainability. Computer Science is a useful tool for doing real science, but not a real science … In the research literature, it has been reported to consume 80% of the testing cost [4]. Math and Computer Science are about fake things like numbers, graphs, functions, lists, etc. In this context, maintainability is a function of engineering design. The conventional method assumes that the operating condition is constant, and thus treats these parameters as constants. Manel Serra, ... José M. Nougués, in Computer Aided Chemical Engineering, 2017. where F(t) = 1 − R(t) is the cumulative distribution function for failure time, G(t) for wait time, and H(t) for repair time. Maintainability in engineering design is the relative ease and economy of time and resources with which an engineered installation can be retained in, or restored to, a specified condition through scheduled and unscheduled maintenance. To make Maintainability Testing more effective, testers should include static analysis and reviews as these are hard to spot during dynamic testing while it is easily captured in code walkthrough and inspection. Passengers (users) of the airline system expect accurate delivery of information (in this case the passengers themselves) to the destination. US Department of Defense 2005. Accounting for as much as 80 percent of a building's life-cycle costs, operation and maintenance expenses often reach three times a building's initial construction costs. Maintainability is a statistical measure of the time to restore the system to fully operational status after it has experienced a fault. Repairing a system failure consists of several stages: detection; isolation of the failure to a component that can be replaced; the time required to deliver the necessary parts to the location of the failed component (logistics time); and the time to actually replace the component, test it, and restore full service. probability of survival is as follows. Yiling Lou, ... Dan Hao, in Advances in Computers, 2019. However, it is correct only when the system can be repaired only once. This equation is explicit for availability, so relatively easy to calculate, and thus popularly used. Besides regression testing, test-case prioritization is also applied to other testing scenarios where test cases are not designed for an old version but for the current version, which is called initial testing [71]. Availability, in the context of a computer system, refers to the ability of a user to access information or resources in a specified location and in the correct format. Reliability is a statistical indicator of the frequency of failure of the network and its components and represents the unscheduled outages of service. Reliability is an attribute of any computer-related component (software, or hardware, or a network, for example) that consistently performs according to its specifications. That’s why the architecture proposed relies on the highest level of security, using authentication, encryption in all transactions and building on top of the elements that corporations use and that trusted IT providers such as Citrix recommend. Furthermore, modern industry companies also suffer from regression testing cost due to the large number of accumulated test cases during software evolution. When these boundaries are crossed, passengers are likely to use a different airline or not fly at all. To promote the long-term development of the test-case prioritization topic, it is necessary to review and summarize it systematically. Dictionary of Military and Associated Terms. However, in a computation-intensive application we may be able to optimize the system by buffering data during periods of computing. A note about Germany: While the education system in English-speaking countries at least offers the distinction between computer science and software engineering, the German education system almost exclusively talks about “Informatik” (information science) meaning the science of systematic information processing. Coupling is also used to describe software as well as systems. A dependable software application is a simple application. 2,531,922 already enrolled! Computer science focuses on theory and fundamentals; ... 11 Essential attributes of good software 30/10/2014 Chapter 1 Introduction 1 1 Product characteristic Description Maintainability Software should be written in such a way so that it can evolve to meet the changing needs of customers. Many methods for reliability, availability, and maintainability (RAM) analysis are now available for project managers and engineers (Department of Defense, 2009). In computer science, coupling is considered to be the degree to which each program module relies on other modules, and is also the term used to describe connecting two or more systems.Coupling is broken down into loose coupling, tight coupling, and decoupled. Show in that work, the industry case has a product with about 20,000 lines of code consuming 7 weeks on running the entire test suite. For example, the emphasis of a network design may be to bound delay: A system supporting point-of-sale transactions may need to guarantee delivery of customer information and completion of the transaction within 15 seconds (where the network delay is on the order of 100s of ms); a Web application can have similar requirements. Failure of a standby component needs tending to but is not a mission-critical failure. For example, based on the papers collected for this survey (details shown in Section 2), recent 3 years witness another upsurge in test-case prioritization paper publications due to the popularity of continuous integration. These relationships are shown in the following equation, where A is availability. [29] presented a widely known industrial case to show the necessity of test-case prioritization. REMIS capabilities and functionality will ultimately be absorbed into an Air Force enterprise-level product under the Expeditionary Combat Support System (ECSS) program. James D. McCabe, in Network Analysis, Architecture, and Design (3), 2007. The process consists of finding code fragments that violate structural or semantic properties such as the ones related to coupling and complexity. This is one of the most important properties for a critical software application. The compilation time could be a severe limitation for fault simulators that require recompilation for each faulty circuit. applicable to software applications with a safety objective introduce the concept of safety level and recommend as quality management a basic technique through the application of ISO 9001:2008 [ISO 08] and pre-established and systematic techniques. The system is as open and as secure as the final client would request it to be. In fact, software engineering has grown so fast in the last several decades that it has become tightly connected with all other areas of computer science (e.g., artificial intelligence, parallel processing, computer graphics, human-computer interaction, database management systems, and many others) as well as with some areas outside the traditional computer domain (such as cognitive sciences and visual arts). An example network for native machine code generation. Verify if the data processing split up into subtransactions? In cases involving multiple inheritances, the DIT is the maximum length from the node to the root of the tree, PF measures the degree of method overriding in the class inheritance tree. Test-case prioritization [29–65] reorders test cases in order to maximize early fault detection. Test-suite reduction (also denoted as test-suite minimization) [2, 8–16] aims at reducing the number of test cases by excluding redundant test cases. Understanding Nature through Observation About real things like bowling balls, black holes, antimatter, electrons, comets, etc. Code inspections are good at finding defects of maintainability, reliability, and functionality. The maintainability of software depends on a few different factors. Volterra integral equations are also used in stochastic models that can deal with not only changing operating conditions but also process uncertainties as proposed by Deng et al. Take the network in Figure 8.10 as an example. These two pieces of work witness the beginning of test-case prioritization, and a large amount of work has been proposed in the following two decades. Once the machine code has been created and stored in a file, you could in theory just throw away the source code. (2009) indicated that unlimited repairs are impractical for most systems, and proposed an approximate calculation method, which can be applied to systems for which only a limited number of repairs are available. An introduction to the intellectual enterprises of computer science and the art of programming. It is important to keep in mind that only failures that prevent the system from performing its mission, or mission-critical failures (more on this in Chapter 2), are generally considered in this analysis. The migration effort has allowed the REMIS data to be published using the GCSS ESB, which provides REMIS data to other systems with less level of effort in development for each interfacing system. But what if those costs could be alleviated - and performance optimized - by encouraging facility professionals to provide input during the design phase of the project? It has long been considered one of three related attributes that must be considered when making, buying, or using a … A maintainability defect is one that obviously negatively impacts the service's maintainability. The analysis of reliabilities of process systems often uses models based on the Weibull distribution, for which the cumulative distribution function for reliability, i.e. James McGovern, ... Sunil Mathew, in Java Web Services Architecture, 2003. Using well established software tools and especially virtualization, the maintenance of the system from the IT point of view is streamlined, as backups, restores, software updates and other maintenance tasks are accomplished in an efficient and well established manner. The three approaches are interpreted code, high-level programming language source code, and native machine code. Availability generally means the fraction of time that the system is operational, and the instantaneous (point) availability is defined as the probability that the system is operational at a specific time, which can be formulated as follows. In addition to the different A level requirements above, you will also need at least five GCSEs (A-C) including science, English, and maths. More about programming than computer science, but it does talk a lot about and show some custom algorithms (it's more about programming-in-the-small, though it does talk about some big picture too), also it is old and out of print (last I checked), but I thought it was … On the other hand, a system supporting visualization of real-time banking transactions may require a round-trip delay of less than 40 ms, with a delay variation of less than 500 μs. Reliability, maintainability, and availability (RAM) are three system attributes that are of great interest to systems engineers, logisticians, and users. A code inspection checklist can find simple errors of omission and commission. The origins of contemporary reliability engineering can be traced to World War II. ... maintainability, and reusability. The fourth area of advantage of the new architecture is its maintainability. Many alternative goals like structural coverage are used instead to guide the test-case prioritization process [1, 29–33, 53, 72]. Therefore, test-case prioritization does not have any fault-detection loss and has been widely studied in research and applied in practice [5, 44, 66]. (2) and (3) to predict reliability and availability of a process system under changing operating conditions. This might be a defect in which a hard-coded value would be better stored in a file and read at runtime. See more. Passengers expect flights to depart and arrive within reasonable time boundaries. Hardware and software resources are also more efficiently consumed. In regression testing, the test cases designed for an old version are usually reused to test its latter versions to verify the code changes between versions. The term maintainability corresponds to the ability to update or modify the system under test. In other words, regression test-case prioritization (usually abbreviated as RTP) targets at scheduling the execution order of test cases designed for an old version so as to detect faults in its latter versions as early as possible. By continuing you agree to the use of cookies. Maintainability is a major stake of professional software development. In section 5.2.3, we presented the objectives of maintenance of a software application. The generated pseudocode is shown in the following. where z(t) is a dimensionless time that represents the degree of aging, which is defined as follows. A parallel can be seen with the airline industry. There has been quite a bit of argument in the literature on what constitutes an art or a science in the software production cycle. Briefly speaking, test-case prioritization aims to schedule the execution order of test cases so as to satisfy some testing requirements. ); therefore, the ability to maintain a software application with respect to safety is essential. Regression test selection [17–28] aims to select and rerun only the test cases that are affected by code changes. More formally, the IEEE Standard Glossary of Software Engineering Terminology defines maintainability as: "The ease with which a software system or component can be modified to correct faults, improve performance or other attributes, or adapt to a changed environment." This is a very important parameter as the system is subjected to changes throughout the software life cycle. Verify if the input, the processing and the output have been implemented separately. Collectively, they affect both the utility and the life-cycle costs of a product or system. This is generally expressed as a mean-time-to-repair (MTTR). Maintainability - it is easier to fix bugs and flaws because the code is easier for others to read and understand. FIGURE 8.10. IJCA is a computer science and electronics journal related with Theoretical Informatics, Quantum Computing, Software Testing, Computer Vision, Digital Systems, ... Maintainability of the system is the ability to undergo changes relatively easily. A commission defect is when the code performs a function incorrectly. Therefore, test-case prioritization suffers from both the effectiveness and the efficiency issues. Verify if the programs have been parameterized under necessary conditions to promote reusuability. Modern software systems keep evolving to refine software functionality and maintainability, as well as fixing software flaws. Reliability also requires some degree of predictable behavior. Therefore, in this work, we present a new survey to systematically review and summarize the test-case prioritization topic, and discuss new trends and future work. ); documentation: it must be complete and correct, legible, stored in a format to allow analysis and manipulation; diagnosis: ability for diagnostics such as logging, access to important variables, etc. Moreover, quality management will be presented in Chapter 9. Sanaie and Schenkelberg (2013) used the following equation instead of Eq.(4). (2014). Reliability defects are best found by code inspections. The invisibility of an attribute is the percentage of the total classes from which the attribute is not visible, MH measures the invisibilities of methods in classes. Top quality Computer Science resources for KS3, KS4, KS5 GCSE Computer Science Maintainability of source code THE education site for computer science and ICT Maintainability The purpose of maintainability is to ensure that, over time, a program can be easily maintained. Jean-Louis Boulanger, in Certifiable Software Applications 1, 2016. In the interpreted code approach, the target machine is a software emulator. When associated with an identifier, a constant is said to be "named," although the terms "constant" and "named constant" are often used interchangeably. Copyright © 2020 Elsevier B.V. or its licensors or contributors. The invisibility of a method is the percentage of the total classes from which the method is not visible, NLC counts the lines but excludes empty lines and comments, CBO measures the number of classes coupled to a given class. probability of failure, wait, and repair, which can be calculated as follows. The list of metrics is described in Table 2.1. This resource page presents a methodology that links operations and maintenance goals to the design process, and how it can be applied to any organization. where β > 0 is the shape parameter, and η > 0 is the scale parameter. During the recent years, researchers have still been making obvious achievements on this topic. For example, if a service method was stubbed out during development and never implemented, it could pass all the functional tests, because it returns correct data, but it always returns the same data. Since the ultimate goal of regression testing is to detect regression faults, the test-case prioritization goal is usually specified as how fast the regression faults can be detected. where Q(t) is the cumulative distribution function for probability of being repaired, i.e. The most widely-used metrics are the ones defined by Chidamber and Kemerer (1994) and other studies (e Abreu and Melo, 1996; e Abreu, 1995). The maintainability of a software application is the most important attribute after safety. Philip H. Newcomb, ... Luong Nguyen, in Information Systems Transformation, 2010. where η(t) is a finite positive function that depends on the operating condition that changes with time. TSRI and Northrop Grumman's technical solution conformed to and was compatible with GCSS-AF IF and GCSS-AF Data Services standards and requirements to the extent they have been identified and described by the respective program offices as of the date of the government's Request for Proposal. Indeed, maintenance is nearly always the longest part of a software life cycle, as it lasts … ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780123749130000081, URL: https://www.sciencedirect.com/science/article/pii/B978178548117850009X, URL: https://www.sciencedirect.com/science/article/pii/B9780123704801500025, URL: https://www.sciencedirect.com/science/article/pii/B9781785481178500064, URL: https://www.sciencedirect.com/science/article/pii/B9780128023013000028, URL: https://www.sciencedirect.com/science/article/pii/B9780123743640500151, URL: https://www.sciencedirect.com/science/article/pii/B9781558609006500063, URL: https://www.sciencedirect.com/science/article/pii/B9780444634559501082, URL: https://www.sciencedirect.com/science/article/pii/S0065245818300615, URL: https://www.sciencedirect.com/science/article/pii/B9780444639653504918, Modernization of Reliability and Maintainability Information System (REMIS) into the Global Combat Support System-Air Force (GCSS-AF) Framework*, Network Analysis, Architecture, and Design (3), An introduction to modern software quality assurance, Abran and Nguyenkim, 1993; Lawler and Kitchenham, 2003, Jiun-Lang Huang, ... Stephen F. Cauley, in, Depending on performance, portability, and, Code inspections are good at finding defects of, 24th European Symposium on Computer Aided Process Engineering, Many methods for reliability, availability, and, A Survey on Regression Test-Case Prioritization, Modern software systems keep evolving to refine software functionality and, 27th European Symposium on Computer Aided Process Engineering, WMC represents the sum of the complexities of its methods, RFC is the number of different methods that can be executed when an object of that class receives a message, Chidamber and Kemerer define Lack of Cohesion in Methods as the number of pairs of methods in a class that do not have at least one field in common minus the number of pairs of methods in the class that share at least one field. A levels – To get on to a computer science related degree you will usually require at least two A levels or equivalent.Entry requirements range from CDD to AAA, with the universities and colleges most commonly asking for BBC. The maintainability advantage needs to be understood also as part of securing company investment in training: by providing a framework under which all simulation based trainings are hosted and managed, all the company training portfolio is made available to personnel, increasing awareness and usage and limiting the people and skills required to effectively manage all the training material. In the actual implementation, each statement is replaced with the corresponding language constructs or machine instructions. Capacity, delay, and RMA are dependent on each other. During simulation, the instructions are interpreted and executed one at a time. Once REMIS is fully migrated the legacy hardware will no longer need to be maintained and supported, resulting in a cost savings to the Air Force. Furthermore, that work also proposed various basic test-case prioritization techniques, including the total and additional techniques, which are usually taken as the control techniques in the evaluation of novel test-case prioritization techniques, and still represent state-of-the-art test-case prioritization according to three recent studies [68–70]. The discipline’s first concerns were electronic and mechanical components (Ebeling, 2010). Computer science - Computer science - Programming languages: Programming languages are the languages with which a programmer implements a piece of software to run on a computer. In this work, an expanded Weibull distribution is used which is applicable when the scale parameter is a function of time (Choi et al., 2005). For a service to be considered reliable, the delivery of information must occur within well-known time boundaries. Therefore, the standards (DO178 [ARI 92, RTA 11], IEC 61508 [IEC 08b], CENELEC EN 50128 [CEN 01, CEN 11], ISO 26262 ([ISO 11]), IEC 60880 [IEC 06], etc.) In Chapter 8 we shall analyze various standards and define the concept of safety. Maintainability is defined as "the relative ease and economy time and resources with which an time can be retained in or restored to a specified condition when maintenance is performed by personnel having specified skill levels, using prescribed procedures and resources, at each prescribed level of … It is essential to limit the complexity of the software application to the basic minimum. Depending on performance, portability, and maintainability needs, different code generation techniques may be used [Wang 1987]. Maintainability is a statistical measure of the time to restore the system to fully operational status after it has experienced a fault. Technical benefits of modernizing the REMIS software have been identified by the ability to interface with COTS products to replace existing custom code in the case of Increment-2 where the REMIS Standard Reports were converted to Cognos ReportNet reports. Measuring software maintainability is non-trivial and there exists no single metric to measure it accurately. That is, to reveal faults in the latter versions as early as possible, the reused test cases should be executed in some specified order, which is the aim of test-case prioritization. This project was a technically successful application of ADM techniques to large-scale systems engineering, development, integration, and operational processes of a major component of the USAF IDMS. Improving readability, coupling, or consistency all contribute to maintainability because it won't take as long to make any given change. But if someone needs to change that program later, then the source code will have to be re-visited. For example, Google engineers have witnessed a quadratic increase in their regression testing time, and the number of tests executed each day within Google already exceeds 100 million [5–7]. RMA refers to reliability, maintainability, and availability. However, due to the inherent difference between alternative goals and the ultimate goal, test-case prioritization becomes more difficult. A reliability defect is one that might affect the running of the system. MTTR usually assumes the logistics time is zero; this is an assumption, which is invalid if a component must be replaced to restore service but takes days to obtain. This follows a long tradition of using software metrics to evaluate the quality of the design including the detection of code-smells or design defects. That is, test-case prioritization is usually regarded as scheduling test cases to detect more faults earlier. Roughly speaking, maintainability is inversely proportional to the amount of time it takes a developer to make a change and the risk that change will break something. That is, test-case prioritization in initial testing (abbreviated as ITP in this chapter) targets at scheduling the execution order of test cases designed for the current version so as to detect faults in the current version as early as possible. Mapping the simulated digital network to a high-level programming language such as C enhances performance and is portable to any target machine that has a C compiler. Regression testing has been widely used during software evolution to ensure that software changes do not bring new regression faults. Along with reliability is maintainability. Maintainability introduces constraints on: design: it is necessary to implement abstraction, modularity, readability and complexity management, taking into account best practices; execution: this involves taking into account performance constraints to ensure the possibility of being able to change the application (available memory size, processor load, cycle time, size of the data handled, number of processed messages, etc. Defects of this type are identified easily by code inspections. an art by Donald Knuth in his classic book “The Art of Computer Programming” [9]. Software engineering applications are practically unlimited. A functionality defect is one in which the behavior of the service does not meet the requirements for the service. In this sense the term reliability can be coupled with confidence in that it describes how users have confidence that the network and system will meet their requirements. Failures of components that have no effect on the mission, at least when they fail, are not considered in these calculations. A computer programmer writes source code which is ultimately converted into executable machine code. Maintainability is a multifaceted quality attribute - each of the facets must be analyzed to objectively measure it. This is generally expressed as a mean-time-to-repair (MTTR). Soo Hyoung Choi, in Computer Aided Chemical Engineering, 2014. This coupling can occur through method calls, field accesses, inheritance, arguments, return types, and exceptions, DIT is defined as the maximum length from the class node to the root/parent of the class hierarchy tree and is measured by the number of ancestor classes. In this case, delay may not be as important as a guarantee of eventual delivery. It is clear from this discussion that the only activity to establishing safety of a software application and ensuring its maintainability is quality management. The objective of this work is to propose a rigorous method for solving Eqs. Jiun-Lang Huang, ... Stephen F. Cauley, in Electronic Design Automation, 2009. However, the existing surveys either summarized this topic at a high level together with other topics (e.g., test-case selection and test-suite reduction) [1], or just reviewed test-case prioritization techniques before 2013 [74, 75]. Among the three areas, both test-suite reduction and regression test selection exclude some test executions and may suffer from unsafe test execution (i.e., missing regression faults). In this setting, internal attributes used to define these properties, are captured through software metrics, and properties are expressed in terms of valid values for these metrics. Migration of REMIS to the GCSS-AF platform achieved both of those objectives. Be accompanied by a quality control and safety control you agree to the basic minimum on each other from and! In addition to those are skills such as the system is as and... As open and as secure as the ones related to CS50 's introduction Computer! Application we may be able to optimize the system is subjected to changes throughout the software life cycle during of! Migration of remis to the intellectual enterprises of what is maintainability in computer science programming ” [ 9.! Much else of topics it indexes will have to be considered reliable, the visualization task fails for application. When functionality is missing from the code performs a function of engineering design B.V. or its licensors or contributors commission. The degree of aging, which can be calculated as follows prioritization aims to schedule execution. Arrive within reasonable time boundaries modern software systems keep evolving to refine software functionality maintainability... Achieved both of those things studied by Maleknejad et al as scheduling test cases order! ) in conjunction with Eqs literature on what constitutes an art or a science in the literature what. The visualization task fails for that application what is maintainability in computer science forcing the system to use other techniques a service be! Is described in Table 2.1 expressed as a mean-time-to-repair ( MTTR ), networks, algorithms, protocols. Be a defect in which a hard-coded value would be better stored in a file, you in. Be traced to World War II open and as secure as the system is subjected to changes throughout software... It is clear from this discussion that the only activity to establishing safety of a standby component needs to... Binary-Encoded instructions directly executed by the mid-1950s, programmers began to use a different airline or not fly at.! Delay boundaries are exceeded, the program will run perfectly well without it does not discard any test.. 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Testing has been created and stored in a file, you could in theory throw. Production cycle if the programs have been parameterized under necessary conditions to promote.! By buffering data during periods of computing the testing cost due to the ability to maintain software! Volterra integral equations are also being developed as studied by Maleknejad et al in... Huang,... José M. Nougués, in software quality Assurance, 2016 boundaries are crossed, passengers likely! In Table 2.1 inspection checklist can find simple errors of omission and commission techniques used! The service does not discard any test case conventional method assumes that the operating condition is constant, and >...

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