Dissertations / Theses: 'Computer maintenance'

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Deraman, Aziz B. "A computer-aided software maintenance process model." Thesis, University of Manchester, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261996.

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Nguyen, Hai Hoang. "Truth maintenance in knowledge-based systems." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/28434/.

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Truth Maintenance Systems (TMS) have been applied in a wide range of domains, from diagnosing electric circuits to belief revision in agent systems. There also has been work on using the TMS in modern Knowledge-Based Systems such as intelligent agents and ontologies. This thesis investigates the applications of TMSs in such systems. For intelligent agents, we use a “light-weight” TMS to support query caching in agent programs. The TMS keeps track of the dependencies between a query and the facts used to derive it so that when the agent updates its database, only affected queries are invalidated and removed from the cache. The TMS employed here is “light-weight” as it does not maintain all intermediate reasoning results. Therefore, it is able to reduce memory consumption and to improve performance in a dynamic setting such as in multi-agent systems. For ontologies, this work extends the Assumption-based Truth Maintenance System (ATMS) to tackle the problem of axiom pinpointing and debugging in ontology-based systems with different levels of expressivity. Starting with finding all errors in auto-generated ontology mappings using a “classic” ATMS [23], we extend the ATMS to solve the axiom pinpointing problem in Description Logics-based Ontologies. We also attempt this approach to solve the axiom pinpointing problem in a more expressive upper ontology, SUMO, whose underlying logic is undecidable.

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Revelle, Meghan Kathleen. "Supporting feature-level software maintenance." W&M ScholarWorks, 2010. https://scholarworks.wm.edu/etd/1539623567.

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Software maintenance is the process of modifying a software system to fix defects, improve performance, add new functionality, or adapt the system to a new environment. A maintenance task is often initiated by a bug report or a request for new functionality. Bug reports typically describe problems with incorrect behaviors or functionalities. These behaviors or functionalities are known as features. Even in very well-designed systems, the source code that implements features is often not completely modularized. The delocalized nature of features makes maintaining them challenging. Since maintenance tasks are expressed in terms of features, the goal of this dissertation is to support software maintenance at the feature-level. We focus on two tasks in particular: feature location and impact analysis via feature coupling.;Feature location is the process of identifying the source code that implements a feature, and it is an essential first step to any maintenance task. There are many existing techniques for feature location that incorporate various types of analyses such as static, dynamic, and textual. In this dissertation, we recognize the advantages of leveraging several types of analyses and introduce a new approach to feature location based on combining dynamic analysis, textual analysis, and web mining algorithms applied to software. The use of web mining for feature location is a novel contribution, and we show that our new techniques based on web mining are significantly more effective than the current state of the art.;After using feature location to identify a feature's source code, maintenance can be completed on that feature. Impact analysis should then be performed to revalidate the system and determine which other features may have been affected by the modifications. We define three feature coupling metrics that capture the relationship between features based on structural information, textual information, and their combination. Our novel feature coupling metrics can be used for impact analysis to quantify the strength of coupling between pairs of features. We performed three empirical studies on open-source software systems to assess the feature coupling metrics and established three major results. First, there is a moderate to strong statistically significant correlation between feature coupling and faults. Second, feature coupling can be used to correctly determine about half of the other features that would be affected by a change to a given feature. Finally, we found that the metrics align with developers' opinions about pairs of features that are actually coupled.

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Vorthmann, Scott A. "Syntax-directed editor support for incremental consistency maintenance." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/9241.

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Taylor, Mark John. "Methodologies and software maintenance." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265393.

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Pound, Graeme Edward. "Ecological models of the maintenance of sexual reproduction." Thesis, University of Southampton, 2001. https://eprints.soton.ac.uk/45919/.

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A generic model of the interaction between sexual and asexual morphs in an ecological context was developed from the lotka-Volterra model of the population dynamics of two competing species (Doncaster, Pound & Cox, 2000). This revealed the threshold difference between the resource niches of sexual and asexual populations that allows coexistence between the two morphs. Coexistence depended on the respective carrying capacities of the sexual and asexual competitors, which we showed to be contingent upon the intrinsic growth capacity of the sexual population. The analytical model was extended to study (a) competition between a sexual population and numerous asexual clones; (b) competition between two metapopulation. A special formulation of Slatkin’s (1974) three-dimensional model of two competing metapopulations was developed with Lotka-Volterra dynamics, which yielded novel predictions for the behaviour of local and regional communities of species. Coexistence between sexual and asexual morphs maybe unsustainable due to the accumulation of clonal diversity over time, and indeed coexistence is rarely observed in nature. To study the dynamics of this accumulation, a stochastic model was developed for competition between asexual clones and a genetically diverse sexual population that exploits a range of resource niches. A model of the accumulation of deleterious mutations over time was incorporated into this framework. Monte-Carlo simulations demonstrated that a sexual population may, over time, exclude asexual clones whose fitness deteriorates due to the accumulation of deleterious mutations. These results suggest that whilst coexistence between sexual and asexual morphs is possible over ecological timescales the long-term outcome of an asexual invasion is determined by: 1) The relationship between genetic variation and niche breadth in the sexual population. 2) The rate as which the relative fitness of the asexual population declines with mutation accumulation. Reciprocal scenarios of the invasion of an asexual population by sexual mutants and sexual colonists are also considered.

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Sihwa, L. "Computer data base assessment of masonry bridges." Thesis, University of Edinburgh, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380434.

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This thesis is concerned about the development of computer data base management system for the assessment of masonry bridges. The various techniques of assessment and remedial measures of masonry bridges are outlined, their shortcomings described. A justification for an alternative method of assessment is given. A review of computer data base management systems is carried out. The reasons for adopting data base management systems is given as well as the reasons for choosing a particular type of data base management system. The common faults associated with masonry structures are described and the problems of identifying these faults are described. The part played by the individual components of a masonry arch bridge is given and the significance of faults on the individual components of the structure is described. A detailed description of the type, in general of the data base system chosen is given followed by a detailed description of a special case of the type chosen, which is the system that was used for the project. A description of how the system was developed is given followed by the way the system operates. A detailed description of how the system can be used is then put forward and the problems associated with the development of the system are outlined. Finally, a description of the implications of the system to the practising engineer is given.

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Nordmark, Fredrik, and Sebastian Ryd. "IndUnd : The Industrial Machine Maintenance Program." Thesis, Mittuniversitetet, Avdelningen för informations- och kommunikationssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-25812.

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Atkins, Henry Hornblower. "Background maintenance utilizing common distributions." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/87372.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.
Includes bibliographical references (leaves 28-29).
by Henry Hornblower Atkins, III.
M.Eng.

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Breidenbach, Jeff. "Survivable software distribution and maintenance." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42793.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
Includes bibliographical references (leaves 79-82).
by Jeff Breidenbach.
Ph.D.

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Gethers, Malcom Bernard II. "Information Integration for Software Maintenance and Evolution." W&M ScholarWorks, 2012. https://scholarworks.wm.edu/etd/1539720326.

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Software maintenance and evolution is a particularly complex phenomenon in the case of long-lived, large-scale systems. It is not uncommon for such systems to progress through years of development history, a number of developers, and a multitude of software artifacts including millions of lines of code. Therefore, realizing even the slightest change may not always be straightforward. Clearly, changes are the central force driving software evolution. Therefore, it is not surprising that a significant effort has been (and should be) devoted in the software engineering community to systematically understanding, estimating, and managing changes to software artifacts. This effort includes the three core change related tasks of (1) expert developer recommendations - identifying who are the most experienced developers to implement needed changes, (2) traceability link recovery recovering dependencies (traceability links) between different types of software artifacts, and (3) software change impact analysis - which other software entities should be changed given a starting point.;This dissertation defines a framework for an integrated approach to support three core software maintenance and evolution tasks: expert developer recommendation, traceability link recovery, and software change impact analysis. The framework is centered on the use of conceptual and evolutionary relationships latent in structured and unstructured software artifacts. Information Retrieval (IR) and Mining Software Repositories (MSR) based techniques are used for analyzing and deriving these relationships. All the three tasks are supported under the framework by providing systematic combinations of MSR and IR analyses on single and multiple versions of a software system. Our approach to the integration of information is what sets it apart from previously reported relevant solutions in the literature. Evaluation on a number of open source systems suggests that such combinations do offer improvements over individual approaches.

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Linares-Vasquez, Mario. "Supporting Evolution and Maintenance of android Apps." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1477068301.

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Mobile developers and testers face a number of emerging challenges. These include rapid platform evolution and API instability; issues in bug reporting and reproduction involving complex multitouch gestures; platform fragmentation; the impact of reviews and ratings on the success of their apps; management of crowd-sourced requirements; continuous pressure from the market for frequent releases; lack of effective and usable testing tools; and limited computational resources for handheld devices. Traditional and contemporary methods in software evolution and maintenance were not designed for these types of challenges; therefore, a set of studies and a new toolbox of techniques for mobile development are required to analyze current challenges and propose new solutions. This dissertation presents a set of empirical studies, as well as solutions for some of the key challenges when evolving and maintaining android apps. In particular, we analyzed key challenges experienced by practitioners and open issues in the mobile development community such as (i) android API instability, (ii) performance optimizations, (iii) automatic GUI testing, and (iv) energy consumption. When carrying out the studies, we relied on qualitative and quantitative analyses to understand the phenomena on a large scale by considering evidence extracted from software repositories and the opinions of open-source mobile developers. From the empirical studies, we identified that dynamic analysis is a relevant method for several evolution and maintenance tasks, in particular, because of the need of practitioners to execute/validate the apps on a diverse set of platforms (i.e., device and OS) and under pressure for continuous delivery. Therefore, we designed and implemented an extensible infrastructure that enables large-scale automatic execution of android apps to support different evolution and maintenance tasks (e.g., testing and energy optimization). In addition to the infrastructure we present a taxonomy of issues, single solutions to the issues, and guidelines to enable large execution of android apps. Finally, we devised novel approaches aimed at supporting testing and energy optimization of mobile apps (two key challenges in evolution and maintenance of android apps). First, we propose a novel hybrid approach for automatic GUI-based testing of apps that is able to generate (un)natural test sequences by mining real applications usages and learning statistical models that represent the GUI interactions. In addition, we propose a multi-objective approach for optimizing the energy consumption of GUIs in android apps that is able to generate visually appealing color compositions, while reducing the energy consumption and keeping a design concept close to the original.

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David, Larry G. "Anatomy of A Software Maintenance Training Program." NSUWorks, 1988. http://nsuworks.nova.edu/gscis_etd/479.

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The process of doing the software training portion of a large complex command and control system under government contract was traced from the initial advertisement to completion of formal training. The Royal Thai Air Defense System (RTADS) contract, as viewed from the perspective of the software training manager, was used as the vehicle for describing the development and delivering a software maintenance training program. The early aspects of the contracting process were reviewed in general terms from the initial public announcement to the contract award. Emphasized, was the need for thorough analysis of the request for proposal (RFP), the system specification, and references included in both. Each included reference could lead to further references and failure to examine all such references could result in underestimating the amount of work needed to complete the contract. Such a failure could result in not bidding enough money to do the job within the proposed schedule. Once the contract was awarded, the processes involved in doing the project were described. These included acquiring and training the necessary staff; analyzing the project needs; coordinating with subcontractors; developing the training and training equipment plan (TTEP); developing budgets and schedules; coordinating with governmental oversight agencies; designing the courses, lessons, and instructional materials; producing the lesson plans, student study guides, and other materials; securing approvals; scheduling students and classes; and finally delivering the planned and prepared training. The problems encountered in coordinating and implementing a program where multiple agencies have shared responsibilities were discussed. Also described were the complications of developing training materials for teaching computer programs that were simultaneously being developed and were thus changing regularly. The added complications associated with training Thai military personnel were covered, such as language and cultural problems. The software maintenance training program was described as it grew from a few lines of general statements in the RFP to about 60 pages of the 800 page TTEP to about 3800 pages of training materials and 500 graphic slides developed specifically for the three software maintenance courses. Those three courses were presented successfully over a two year period to three different groups of people. Conclusions emphasized the need to plan in great detail, to expect problems, to coordinate with everyone concerned, to adhere to budgets and schedules, and to expect to expend much time and energy on student personal matters because of cultural and language difficulties. The RTADS software maintenance training program was evaluated as successful by all concerned, all students completed their training, and all students safely returned home to Thailand.

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Doyle, Leo F. "A guide for the selection and maintenance of computer peripherals." Virtual Press, 1991. http://liblink.bsu.edu/uhtbin/catkey/834517.

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This thesis is a resource document for computer information that is not presently available as a single unit. It describes most of the commonly available computer peripherals and some not-so-common ones from the micro, mini, and mainframe computer worlds. Physical descriptions, methods of operation, trouble shooting, maintenance, and some schematics and future trends are covered. A few older devices having historical significance are also discussed.By knowing where the computer industry is currently and seeing where it has been hardware-wise, it should be possible to project the direction in which the computer industry is headed. People in the computer profession and people that use computers need to be educated about peripheral devices so that they may make informed decisions on which equipment to acquire and in planning for the future. This thesis should be a valuable aid in this process. The information presented should save time and money during the decision-making process and lead to more effective choices of equipment.
Department of Computer Science

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Smith, Alistair J. "Maintenance scheduling in the electricity industry." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299585.

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Sayyad, Shirabad Jelber. "Supporting software maintenance by mining software update records." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/29004.

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It is well known that maintenance is the most expensive stage of the software life cycle. Most large real world software systems consist of a very large number of source code files. Important knowledge about different aspects of a software system is embedded in a rich set of implicit relationships among these files. Those relationships are partly reflected in system documentation at its different levels, but more often than not are never made explicit and become part of the expertise of system maintainers. Finding existing relations between source code components is a difficult task, especially in the case of legacy systems. When a maintenance programmer is looking at a piece of code in a source file, one of the important questions that he or she needs to answer is: "which other files should I know about, i.e. what else might be relevant to this piece of code?". This is an example of a more general Relevance Relation that maps a set of entities in a software system into a relevance value. How can we discover and render explicit these relationships without looking over the shoulder of a programmer involved in a maintenance task? We turn to inductive methods that are capable of extracting structural patterns or models from data. They can learn concepts or models from experience observed in the past to predict outcomes of future unseen cases. This thesis lies at the intersection of two research fields, which has been widely ignored by researchers in the machine learning and software engineering communities. It investigates the application of inductive methods to daily software maintenance at the source code level. Therefore in this thesis we first lay out the general idea of relevance among different entities in a software system. Then using inductive learning methods and a variety of data sources used by maintenance programmers, we extract (i.e. learn) what we call a maintenance relevance relation among files in a large legacy system. In effect we learn from past maintenance experience in the form of problem reports and update records, to be able to make predictions that are useful in future maintenance activities. This relation, which is called the Co-update relation, predicts whether updating one source file may require a change in another file. To learn the Co-update relation we have performed a large number of experiments using syntactic features such as function calls or variable definitions. We have also performed experiments that use text based features such as source code comments and problem reports, and the combination of these features. The results obtained show that while using syntactic features is encouraging in terms of the predictive power of the results of learning, using text based features yields highly accurate models, with precision and recall measures that make these models viable to be used in a real world setting. As part of the contribution of this thesis we also report on challenges encountered in the process and the lessons learned.

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Williams, Michael J. "Training Aviation Maintenance Technicians with Information Retrieval Systems." NSUWorks, 2000. http://nsuworks.nova.edu/gscis_etd/924.

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The goal of this dissertation has been to examine changes in computing technology skills possessed by aircraft maintenance technicians. The perspective of this project has been from that of a Federal Aviation Administration (FAA) approved Aviation Maintenance Technician School (AMTS). Specifically, the AMTS curriculum at Embry-Riddle Aeronautical University (ERAU) in Daytona Beach, Florida, provided participants for the study. Recommendations for integrating computing technology training into the AMTS curriculum at ERAU are being proposed for planned changes to the existing curriculum. With the increased availability of computerized documentation and reference materials for the aviation industry, many technical training institutions are becoming aware of the importance of computing technology skills to the aircraft technician. With the continuing explosion of the Internet and availability of other technology-based systems, the question of what skills are already possessed will be significant in the development of any new training. A literature review has been conducted to determine the current status of computing technology within both the aviation maintenance field and as used by aircraft technician training programs. The use of such technology is quite extensive and is rapidly gaining acceptance throughout the aviation industry. In an effort to determine the computing technology skills currently possessed by aircraft maintenance students, a study was conducted that compared computer familiarity and user accuracy. The study consisted of two separate phases conducted two years apart. Identical computer software and hardware was used for each phase of the study. Instruments used included a survey of current computer skills, exercises to determine computer use, and a Subjective evaluation of two different FAA documentation software packages. Analysis of the data determined that computing technology skills possessed by AMTS students at ERAU have not significantly changed in the two years spanning the two phases of this study. These results are being used to provide recommendations for changes to AMTS curricula concerning the level of computing technology skills to be presented. While there is presently no such training required by the FAA for approved AMTSs, results from this study point to a need for exposure to computers throughout the AMTS curriculum.

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Lelli, leitao Valeria. "Testing and maintenance of graphical user interfaces." Thesis, Rennes, INSA, 2015. http://www.theses.fr/2015ISAR0022/document.

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La communauté du génie logiciel porte depuis ses débuts une attention spéciale à la qualité et la fiabilité des logiciels. De nombreuses techniques de test logiciel ont été développées pour caractériser et détecter des erreurs dans les logiciels. Les modèles de fautes identifient et caractérisent les erreurs pouvant affecter les différentes parties d’un logiciel. D’autre part, les critères de qualité logiciel et leurs mesures permettent d’évaluer la qualité du code logiciel et de détecter en amont du code potentiellement sujet à erreur. Les techniques d’analyses statiques et dynamiques scrutent, respectivement, le logiciel à l’arrêt et à l’exécution pour trouver des erreurs ou réaliser des mesures de qualité. Dans cette thèse, nous prônons le fait que la même attention doit être portée sur la qualité et la fiabilité des interfaces utilisateurs (ou interface homme-machine, IHM), au sens génie logiciel du terme. Cette thèse propose donc deux contributions dans le domaine du test et de la maintenance d’interfaces utilisateur : 1. Classification et mutation des erreurs d’interfaces utilisateur. 2. Qualité du code des interfaces utilisateur. Nous proposons tout d’abord un modèle de fautes d’IHM. Ce modèle a été conçu à partir des concepts standards d’IHM pour identifier et classer les fautes d’IHM ; Au travers d’une étude empirique menée sur du code Java existant, nous avons montré l’existence d’une mauvaise pratique récurrente dans le développement du contrôleur d’IHM, objet qui transforme les évènements produits par l’interface utilisateur pour les transformer en actions. Nous caractérisons cette nouvelle mauvaise pratique que nous avons appelée Blob listener, en référence à la méthode Blob. Nous proposons également une analyse statique permettant d’identifier automatiquement la présence du Blob listener dans le code d’interface Java Swing
The software engineering community takes special attention to the quality and the reliability of software systems. Software testing techniques have been developed to find errors in code. Software quality criteria and measurement techniques have also been assessed to detect error-prone code. In this thesis, we argue that the same attention has to be investigated on the quality and reliability of GUIs, from a software engineering point of view. We specifically make two contributions on this topic. First, GUIs can be affected by errors stemming from development mistakes. The first contribution of this thesis is a fault model that identifies and classifies GUI faults. We show that GUI faults are diverse and imply different testing techniques to be detected. Second, like any code artifact GUI code should be analyzed statically to detect implementation defects and design smells. As for the second contribution, we focus on design smells that can affect GUIs specifically. We identify and characterize a new type of design smell, called Blob listener. It occurs when a GUI listener, that gathers events to treat and transform as commands, can produce more than one command. We propose a systematic static code analysis procedure that searches for Blob listener that we implement in a tool called InspectorGuidget. Experiments we conducted exhibits positive results regarding the ability of InspectorGuidget in detecting Blob listeners. To counteract the use of Blob listeners, we propose good coding practices regarding the development of GUI listeners

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Morrison, David J. "Prediction of software maintenance costs." Thesis, Edinburgh Napier University, 2001. http://researchrepository.napier.ac.uk/Output/3601.

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This thesis is concerned with predicting the costs of maintaining a computer program prior to the software being developed. The ubiquitous nature of software means that software maintenance is an important activity, and evidence exists to support the contention that it is the largest and most costly area of endeavour within the software domain. Given the levels of expenditure associated with software maintenance, an ability to quantify future costs and address the determinants of these costs can assist in the planning and allocation of resources. Despite the importance of this field only a limited understanding of the factors that determine future maintenance costs exists, and maintenance estimation is more frequently applied to existing software. A hypothesis has been postulated that suggests the inherent maintainability of the software, the scale of the activity and the degree of change that pertains will determine future software maintenance costs. The variables that contribute to the maintainability of the software have been explored through a survey of past projects, which was undertaken using a questionnaire. This was designed with assistance from three separate teams of professional software engineers. The questionnaire requires 69 numerical or ordinal responses to a series of questions pertaining to characteristics including program structure, computer architecture, software development methodology, project management processes and maintenance outcomes. Factor analysis methods were applied and five of the most powerful predictors are identified. A linear model capable of predicting maintainability has been developed. Validation was undertaken through a series of follow-up interviews with several survey respondents, and by further statistical analysis utilising hold-out samples and structural equation modelling. The model was subsequently used to develop predictive tools intended to provide management support by both providing a categorical assessment of future maintainability, and a quantitative estimate of probable maintenance costs. The distinction between essential corrective maintenance, and other elective forms of maintenance is considered. Conclusions are drawn regarding the efficacy and limitations of tools that can be developedt o supportm anagemendt ecisionm aking. Subjectt o further work with a largers ampleo f projects,p referablyf rom within a singleo rganisationi,t is concluded i that useful tools could be developed to make both categorical ('acceptable' versus 'not acceptable') and static (initial) quantitative predictions. The latter is dependent on the availability of a software development estimate. Some useful predictive methods have also been applied to dynamic (continuing) quantitative prediction in circumstances where a trend develops in successive forecasts. Recommendationfosr furtherw ork arep rovided.T hesei nclude: U Factor analysis and linear regression has been applied to a sample of past software projects from a variety of application areas to identify important input variables for use in a maintainability prediction model. Maintainability is regarded as an important determinant of maintenance resource requirements. The performance of these variables within a single organisation should be confirmed by undertaking a further factor analysis and linear regression on projects from within the target organisation. u The robustness of model design within this target organisation should be considered by applying a sensitivity analysis to the input variables. u This single organisation maintainability predictor model design should be validated by confirmatory interviews with specialists and users from within the target organisation. u Aggregate scale has been identified as another predictor of overall maintenance resource requirements, and the relationship between development and maintenance effort explored for the general case. It is desirable that development and corrective maintenance scale relationships should be explored within a single organisation. Within this environment the association between standardised effort and maintainability should be confirmed, and the value of the logistic model as a descriptor of the relationship verified. u The approacht o quantifying non-correctivem aintenanceth at has been outlined requiresf iirther developmentT. he relationshipb etweena nnualc hanget raffic and maintenancec ostss houldb e modelled,a ssuminga prior knowledgeo f the scale and maintainability determinants. uA sensitivity analysis should be applied to the predictive system that has been developed, recognising the potential for error in the values of the input variables that may pertain. uA goal of this further research should be the development of a suite of soft tools, designed to enable the user to develop a software maintenance estimation system.

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Andersson, Ola. "Benchmarking of Data Warehouse Maintenance Policies." Thesis, University of Skövde, Department of Computer Science, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-472.

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Many maintenance policies have been proposed for refreshing a warehouse. The difficulties of selecting an appropriate maintenance policy for a specific scenario with specific source characteristics, user requirements etc. has triggered researcher to develop algorithms and cost-models for predicting cost associated with a policy and a scenario. In this dissertation, we develop a benchmarking tool for testing scenarios and retrieve real world data that can be compared against algorithms and cost-models. The approach was to support a broad set of configurations, including the support of source characteristics proposed in [ENG00], to be able to test a diversity set of scenarios.

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Wong, Andria H. "Database maintenance for a video editing system." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/15109.

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Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaves [1]-2 (fifth set).
by Andria H. Wong.
B.S.

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El-Sayed, Maged F. "Incremental maintenance of materialized Xquery views." Link to electronic dissertation, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-082305-120333/.

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Williamsson, Ia. "Total Quality Maintenance (TQMain) A predictive and proactive maintenance concept for software." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2281.

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This thesis describes an investigation of the possibility to apply a maintenance concept originally developed for the industry, on software maintenance. Today a large amount of software development models exist but not many of them treat maintenance as a part of the software life cycle. In most cases maintenance is depicted as an activity towards the end of the software life cycle. The high cost ascribed to software maintenance motivates for improvements. The maintenance concept TQMain proposed in this thesis distinguishes from other maintenance concepts by its use of preventive, predictive and proactive maintenance strategies. TQMain uses a common database to store real-time data from various departments and uses it for analyse and assessment to track the development of deviations in the condition of the production process and product quality at an early stage. A continuous cyclic improvement of the maintenance strategy is reached by comparing the data from the real-time measurements with data from the database. The ISO/IEC Software engineering – Product qualities is used as a source of empiric data to conclude that the correct quality characteristics are used for identifying software product quality and its characteristics and compare them with the characteristics of industrial product quality. The results presented are that in the conceptual outline of TQMain measures are obviously not the same as in software maintenance, but the aspect of product quality is common for both. The continuous cyclic improvement of the product quality that TQMain features together with the aspect of detecting potential failures before they occur would, judging from the conceptual outline of TQMain be applicable on software maintenance.

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李守敦 and Sau-dan Lee. "Maintenance of association rules in large databases." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31215531.

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Lee, Sau-dan. "Maintenance of association rules in large databases /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19003250.

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Bodington, R. "Truth maintenance and constraint satisfaction in model-based vision." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277136.

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Bischoff, Douglas A. "Analysis and evaluation of computer support for afloat submarine IMA maintenance planning." Thesis, Monterey, California. Naval Postgraduate School, 1990. http://hdl.handle.net/10945/30676.

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Approved for public release, distribution is unlimited
Late identification of work and inadequate administrative controls are principle causes of untimely preparation of Controlled Work Procedures (CWPs) at one heavily loaded, afloat, submarine Intermediate Maintenance Activity (IMA). Untimely CWP preparation, however, is symptomatic of a more widespread problem of inadequate communications and decision support in the IMA maintenance planning process. The Maintenance Resource Management System's (MRMS) Engineered Time Value standards provide significant improvement in resource estimation accuracy over the Maintenance and Material Management (3-M) Intermediate Maintenance Management System (IMMS). However, both IMMS and MRMS (version 0) emphasize transaction processing and structured, upline reporting. Neither system provides tools necessary for optimal decision making to IMA maintenance supervisors.

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Krishnamaraja, Magesh. "Extracting Maintenance Knowledge from Vehicle Databases." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-24586.

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Every vehicle or truck manufacturer maintains databases regarding the service information oftheir vehicles. In this thesis, two vehicle databases: Vehicle Specification Database andMaintenance Service Database are analyzed and compared. The purpose is to explore theconnection between vehicle specification and vehicle maintenance needs. The approach is touse different clustering algorithms(Hierarchical, K-means, Spectral), distance measures (PositiveMatching Index and a modified Positive Matching Index), cluster validity measures(Rand Index,Jaccard Index) and data representations(Binary, Frequency) on these databases to determinethe important maintenance related specification attributes and their relation to differentservice problems (e.g. engine, brake, clutch) The clustering results indicate that there is arelation between vehicle specification and vehicle maintenance profiles. Different data miningrules that connect vehicle specification with vehicle maintenance needs are derived from theclustering results.

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Gold, Nicolas Edwin. "Hypothesis-based concept assignment to support software maintenance." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4535/.

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Software comprehension is one of the most expensive activities in software maintenance and many tools have been developed to help the maintainer reduce the time and cost of the task. Of the numerous tools and methods available, one group has received relatively little attention: those using plausible reasoning to address the concept assignment problem. This problem is defined as the process of assigning descriptive terms to their implementation in source code, the terms being nominated by a user and usually relating to computational intent. It has two major research issues: Segmentation: finding the location and extent of concepts in the source code.Concept Binding', determining which concepts are implemented at these locations. This thesis presents a new concept assignment method: Hypothesis-Based Concept Assignment (HB-CA). A framework for the activity of software comprehension is defined using elements of psychological theory and software tools. In this context, HB-CA is presented as a successful concept assignment method for COBOL II, employing a simple knowledge base (the library) to model concepts, source code indicators, and inter-concept relationships. The library and source code are used to generate hypotheses on which segmentation and concept binding are performed. A two-part evaluation is presented using a prototype implementation of HB-CA. The first part shows that HB-CA has linear computational growth in the length of program under analysis. Other characteristics addressed include HB-CA's scalability, its applicability to other languages, the contribution made by different information sources, domain independence, representational power, and guidelines for the content of the library. The first part concludes by comparing the method and implementation to cognitive requirements for software comprehension tools. The second part considers applications of HB-CA in software maintenance. Five areas for potential cost reduction are identified: business-rule ripple analysis, code ripple analysis, module selection, software reuse, and software module comprehension.

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Calliss, Frank William. "Inter-module code analysis techniques for software maintenance." Thesis, Durham University, 1989. http://etheses.dur.ac.uk/6550/.

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The research described in this thesis addresses itself to the problem of maintaining large, undocumented systems written in languages that contain a module construct. Emphasis is placed on developing techniques for analysing the code of these systems, thereby helping a maintenance programmer to understand a system. Techniques for improving the structure of a system are presented. These techniques help make the code of a system easier to understand. All the code analysis techniques described in this thesis involve reasoning with, and manipulating, graphical representations of a system. To help with these graph manipulations, a set of graph operations are developed that allow a maintenance programmer to combine graphs to create a bigger graph, and to extract subgraphs from a given graph that satisfy specified constraints. A relational database schema is developed to represent the information needed for inter-module code analysis. Pointers are given as to how this database can be used for inter-module code analysis.

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Wang, Cishen. "Maintenance of a 3D Visualization System." Thesis, Växjö University, School of Mathematics and Systems Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2320.

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Vizz3D is a powerful 3D visualization system. The current version is neither perfect nor up-to-date. Furthermore, some important features are missing. In order to keep the tool valuable it needs to be maintained. I implemented a new feature allowing to save and load the view port in the graph to control the camera position. I also improved the CPU utilization and the navigation system to solve the limitations in Vizz3D and to improve the overall performance.

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Shepherd, David. "Natural language program analysis combining natural language processing with program analysis to improve software maintenance tools /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 176 p, 2007. http://proquest.umi.com/pqdweb?did=1397920371&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Schoen, Pepijn. "Improving robustness of ITER maintenance schedules." Thesis, Linnéuniversitetet, Institutionen för datavetenskap (DV), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-30529.

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In the experimental ITER fusion reactor, currently under construction in Cadarache, France, components close to the plasma will get activated and contaminated over time. Therefore, these components will need to be maintained remotely in a so called hot cell facility. The maintenance will be executed according to step-by-step procedures, with every procedure meticulously validated and formally described in an Operation Sequence Description (OSD). To support formal validation, OSDs are to be captured in an ITER-dedicated Structured Language (SL), a form of domain specific programming language. The Remote Handling Study Centre (RHSC), located at FOM institute DIFFER, Nieuwegein, The Netherlands, has an ITER Remote Handling Control Room representative setup which connects to a virtual ITER Hot Cell back-end environment. In this setup, Remote Handling maintenance scenarios and procedures can be tested under realistic conditions. In this thesis, a Structured Language for ITER maintenance is proposed, implemented as a prototype to capture several realistic operational sequences from existing projects, and integrated in the RHSC workflow. The Structured Language programs are converted to schedulable tasks, by inferring their resource usage and time duration from the structured task descriptions. These tasks are then scheduled using a proposed set of scheduling heuristics. The resulting schedule is subsequently submitted to many simulated executions, with random variation in the execution time of individual tasks. The variation that is applied in the execution time, is based on representative task execution times was measured for a recent and repetitive set of maintenance tasks performed at JET. It is shown that inserting a certain amount of slack in the schedule improves its robustness. ITER maintenance scheduling should account for uncertainty by including slack in the resulting planning.

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Seddon, Jonathan Jeremy Marcus. "FASMA : an anthropocentric decision support system for maintenance management." Thesis, Brunel University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302771.

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Alhindawi, Nouh. "Supporting source code comprehension during software evolution and maintenance." Thesis, Kent State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3618939.

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This dissertation addresses the problems of program comprehension to support the evolution of large-scale software systems. The research concerns how software engineers locate features and concepts along with categorizing changes within very large bodies of source code along with their versioned histories. More specifically, advanced Information Retrieval (IR) and Natural Language Processing (NLP) are utilized and enhanced to support various software engineering tasks. This research is not aimed at directly improving IR or NLP approaches; rather it is aimed at understanding how additional information can be leveraged to improve the final results. The work advances the field by investigating approaches to augment and re-document source code with different types of abstract behavior information. The hypothesis is that enriching the source code corpus with meaningful descriptive information, and integrating this orthogonal information (semantic and structural) that is extracted from source code, will improve the results of the IR methods for indexing and querying information. Moreover, adding this new information to a corpus is a form of supervision. That is, apriori knowledge is often used to direct and supervise machine-learning and IR approaches.

The main contributions of this dissertation involve improving on the results of previous work in feature location and source code querying. The dissertation demonstrates that the addition of statically derived information from source code (e.g., method stereotypes) can improve the results of IR methods applied to the problem of feature location. Further contributions include showing the effects of eliminating certain textual information (comments and function calls) from being included when performing source code indexing for feature/concept location. Moreover, the dissertation demonstrates an IR-based method of natural language topic extraction that assists developers in gaining an overview of past maintenance activities based on software repository commits.

The ultimate goal of this work is to reduce the costs, effort, and time of software maintenance by improving the results of previous work in feature location and source code querying, and by supporting a new platform for enhancing program comprehension and facilitating software engineering research.

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Hays, Lindsey B. "Predicting Class Life Cycle Maintenance Effort Based on Class Complexity." UNF Digital Commons, 2007. http://digitalcommons.unf.edu/etd/247.

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In the software industry today many programmers spend countless hours maintaining existing Java programs. The cost of code maintenance affects a company in many ways such as the budget, time management and resources. Making management decisions regarding these issues could be assisted, if maintenance cost of Java classes could be predicted. The goal of this thesis was to create a new model predicting the maintenance effort based on the Java class complexity. It seems clear the complexity of a Java class can directly relate to the amount of time it will take to perform maintenance on the class. To develop the new maintenance effort model, a test bed of Java classes was assembled representing a sample of Java classes from the workplace. Then a variety of Java class metrics were calculated using these classes. Using the backward elimination process of regression analysis in SPSS, a new model was created predicting maintenance effort. The metrics that best predicted maintenance effort were the depth of an inheritance tree, the number of times a class has been deployed to the customer and the lines of code. Together, these metrics together were able to predict 85% of the maintenance effort on the set of Java classes tested.

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Kinloch, David A. "A combined representation for the maintenance of C programs." Thesis, Durham University, 1995. http://etheses.dur.ac.uk/4883/.

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A programmer wishing to make a change to a piece of code must first gain a full understanding of the behaviours and functionality involved. This process of program comprehension is difficult and time consuming, and often hindered by the absence of useful program documentation. Where documentation is absent, static analysis techniques are often employed to gather programming level information in the form of data and control flow relationships, directly from the source code itself. Software maintenance environments are created by grouping together a number of different static analysis tools such as program sheers, call graph builders and data flow analysis tools, providing a maintainer with a selection of 'views' of the subject code. However, each analysis tool often requires its own intermediate program representation (IPR). For example, an environment comprising five tools may require five different IPRs, giving repetition of information and inefficient use of storage space. A solution to this problem is to develop a single combined representation which contains all the program relationships required to present a maintainer with each required code view. The research presented in this thesis describes the Combined C Graph (CCG), a dependence-based representation for C programs from which a maintainer is able to construct data and control dependence views, interprocedural control flow views, program slices and ripple analyses. The CCG extends earlier dependence-based program representations, introducing language features such as expressions with embedded side effects and control flows, value returning functions, pointer variables, pointer parameters, array variables and structure variables. Algorithms for the construction of the CCG are described and the feasibility of the CCG demonstrated by means of a C/Prolog based prototype implementation.

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Hao, Zhong. "Augmented Reality On Radio Base Station Maintenance." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-84479.

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Radio base station(RBS) is the key infrastructure in wireless network and the main product of Ericsson. To improve the efficiency and success rate of RBS maintenance is therefore necessary and beneficial to Ericsson. Augmented reality is a promising solution by annotating computer generated guiding information on real world to enhance the information received during the maintenance. This thesis developed a workable AR application for RBS to evaluate the feasibility and difficulty of applying AR on RBS. Based on Android platform, the application used Vuforia from Qualcomm and Unity as tracking and rendering package respectively. Tracked result was imported to Unity and processed by low pass filters to remove noise. Filtered data was then used to build a distributed world coordinate frame array to cover the entire RBS panel. On this distributed world coordinate frame array, digital contents such as audio, animation were placed and controlled by a task state machine. Drove by the user control in user interface layer, the task state machine provide a flexible task scheduling scheme for task navigation. At last, digital contents and real time video captured by phone camera were synthesized and rendered on the cellphone screen. The result presented a practicable AR solution for RBS maintenance and reveals the advantages and disadvantages of deploying AR technology for RBS. Certain suggestions were also described based on the development.

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Ishakbeyoglu, Naci Selim. "Maintenance of semantic integrity constraints in database systems." Case Western Reserve University School of Graduate Studies / OhioLINK, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=case1061306318.

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Lu, Zhenxin, and 蘆振鑫. "Location-aware routing with reduced location maintenance routing for Ad hoc networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B29737308.

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Gibbins, Wilson K. "The relationship among commenting style, software complexity metrics, and software maintainability." Thesis, This resource online, 1988. http://scholar.lib.vt.edu/theses/available/etd-04122010-083707/.

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Bundy, Gary Neal. "Assessing software quality in Ada based products with the objectives, principles, attributes framework." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-06112009-063410/.

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Shaikh, Jamil. "Energy efficient dominating set based topology maintenance in ad hoc wireless networks." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26768.

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In a multi-hop wireless network, each node is able to send a message to all of its neighbors that are located within its transmission radius. In a broadcasting task, a source sends the same message to the entire network. The routing problem deals with finding a route between a source and a destination. In the activity-scheduling problem, each node decides between active or passive state. We present a scheme whose goal is to prolong network life while preserving connectivity. Each node is either active or has an active neighbor node. Routing and broadcasting are restricted to active nodes that create such dominating set. Activity status is periodically updated during a short transition period. The main contribution of this thesis is to propose new metrics for previously studied source independent localized dominating sets, based on combinations of node degrees and remaining energy levels, for deciding activity status. Furthermore, our implementation of new metrics enhanced the life span of each node and whole network for 12% to 29%. We argue that our new approach can outperform conventional 802.11, conventional dominating set based ad hoc networks and span in terms of capacity, latency, and power savings.

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Werbelow, Wayne Louis. "The application of artificial intelligence techniques to software maintenance." Thesis, Kansas State University, 1985. http://hdl.handle.net/2097/9890.

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Baerisch, Stefan. "Domain-specific model-driven testing." Wiesbaden : Vieweg+Teubner Research, 2010. http://site.ebrary.com/id/10382671.

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Murphy, Gail C. "Lightweight structural summarization as an aid to software evolution /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/6976.

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Futcher, Lynn Ann. "A model for integrating information security into the software development life cycle." Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/506.

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It is within highly integrated technology environments that information security is becoming a focal point for designing, developing and deploying software applications. Ensuring a high level of trust in the security and quality of these applications is crucial to their ultimate success. Therefore, information security has become a core requirement for software applications, driven by the need to protect critical assets and the need to build and preserve widespread trust in computing. However, a common weakness that is inherent in the traditional software development methodologies is the lack of attention given to the security aspects of software development. Most of these methodologies do not explicitly include a standardised method for incorporating information security into their life cycles. Meaningful security can be achieved when information security issues are considered as part of a routine development process, and security safeguards are integrated into the software application throughout its life cycle. This, in turn, will lead to users being more confident to use software applications, and to entrust today's computer systems with their personal information. To build better or more secure software, an improved software development process is required. Security of a software application must be based on the risk associated with the application. In order to understand this risk, the relevant information assets need to be identified together with their threats and vulnerabilities. Therefore, security considerations provide input into every phase of the Software Development Life Cycle (SDLC), from requirements gathering to design, implementation, testing and deployment. This research project presents a Secure Software Development Model (SecSDM) for incorporating information security into all phases of the SDLC, from requirements gathering to systems maintenance. The SecSDM is based on many of the recommendations provided by relevant international standards and best practices, for example, the ISO 7498-2 (1989) standard which addresses the underlying security services and mechanisms that form an integral part of the model.

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Dobrynin, Mikhail. "Using intelligent agents for complex software systems maintenance." Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1174588678.

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Cheung, Kai-man Felix, and 張繼文. "Efficient algorithms for semantic net construction and maintenance." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31227259.

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Hamza-Lup, Felix George. "DYNAMIC SHARED STATE MAINTENANCE IN DISTRIBUTED VIRTUAL ENVIRONMENTS." Doctoral diss., University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4407.

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Advances in computer networks and rendering systems facilitate the creation of distributed collaborative environments in which the distribution of information at remote locations allows efficient communication. Particularly challenging are distributed interactive Virtual Environments (VE) that allow knowledge sharing through 3D information. In a distributed interactive VE the dynamic shared state represents the changing information that multiple machines must maintain about the shared virtual components. One of the challenges in such environments is maintaining a consistent view of the dynamic shared state in the presence of inevitable network latency and jitter. A consistent view of the shared scene will significantly increase the sense of presence among participants and facilitate their interactive collaboration. The purpose of this work is to address the problem of latency in distributed interactive VE and to develop a conceptual model for consistency maintenance in these environments based on the participant interaction model. A review of the literature illustrates that the techniques for consistency maintenance in distributed Virtual Reality (VR) environments can be roughly grouped into three categories: centralized information management, prediction through dead reckoning algorithms, and frequent state regeneration. Additional resource management methods can be applied across these techniques for shared state consistency improvement. Some of these techniques are related to the systems infrastructure, others are related to the human nature of the participants (e.g., human perceptual limitations, area of interest management, and visual and temporal perception). An area that needs to be explored is the relationship between the dynamic shared state and the interaction with the virtual entities present in the shared scene. Mixed Reality (MR) and VR environments must bring the human participant interaction into the loop through a wide range of electronic motion sensors, and haptic devices. Part of the work presented here defines a novel criterion for categorization of distributed interactive VE and introduces, as well as analyzes, an adaptive synchronization algorithm for consistency maintenance in such environments. As part of the work, a distributed interactive Augmented Reality (AR) testbed and the algorithm implementation details are presented. Currently the testbed is part of several research efforts at the Optical Diagnostics and Applications Laboratory including 3D visualization applications using custom built head-mounted displays (HMDs) with optical motion tracking and a medical training prototype for endotracheal intubation and medical prognostics. An objective method using quaternion calculus is applied for the algorithm assessment. In spite of significant network latency, results show that the dynamic shared state can be maintained consistent at multiple remotely located sites. In further consideration of the latency problems and in the light of the current trends in interactive distributed VE applications, we propose a hybrid distributed system architecture for sensor-based distributed VE that has the potential to improve the system real-time behavior and scalability.
Ph.D.
School of Computer Science;
Engineering and Computer Science;
Engineering and Computer Science

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Dissertations / Theses on the topic 'Computer maintenance'

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