925 resultados para Experimental software engineering
Resumo:
Opinnäytetyö etsii korrelaatiota ohjelmistomittauksella saavutettujen tulosten ja ohjelmasta löytyneiden virheiden väliltä. Työssä käytetään koeryhmänä jo olemassaolevia ohjelmistoja. Työ tutkii olisiko ohjelmistomittareita käyttämällä ollut mahdollista paikallistaa ohjelmistojen ongelmakohdat ja näin saada arvokasta tietoa ohjelmistokehitykseen. Mittausta voitaisiin käyttää resurssien parempaan kohdentamiseen koodikatselmuksissa, koodi-integraatiossa, systeemitestauksessa ja aikataulutuksessa. Mittaamisen avulla nämä tehtävät saisivat enemmän tietoa resurssien kohdistamiseen. Koeryhmänä käytetään erilaisia ohjelmistotuotteita. Yhteistä näille kaikille tuotteille on niiden peräkkäiset julkaisut. Uutta julkaisua tehtäessä, edellistä julkaisua käytetään pohjana, jonka päällekehitetään uutta lähdekoodia. Tämän takia ohjelmistomittauksessa pitää pystyä erottelemaan edellisen julkaisun lähdekoodi uudesta lähdekoodista. Työssä käytettävät ohjelmistomittarit ovat yleisiä ja ohjelmistotekniikassalaajasti käytettyjä mittaamaan erilaisia lähdekoodin ominaisuuksia, joiden arvellaan vaikuttavan virhealttiuteen. Tämän työn tarkoitus on tutkia näiden ohjelmistomittareiden käytettävyyttä koeryhmänä toimivissa ohjelmistoympäristöissä. Käytännön osuus työstä onnistui löytämään korrelaation joidenkinohjelmistomittareiden ja virheiden väliltä, samalla kuin toiset ohjelmistomittarit eivät antaneet vakuuttavia tuloksia. Ohjelmistomittareita käyttämällä näyttää olevan mahdollista tunnistaa virhealttiit kohdat ohjelmasta ja siten parantaa ohjelmistokehityksen tehokkuutta. Ohjelmistomittareiden käyttö tuotekehityksessäon perusteltavaa ja niiden avulla mahdollisesti pystyttäisiin vaikuttamaan ohjelmiston laatuun tulevissa julkaisuissa.
Resumo:
We propose a new approach and related indicators for globally distributed software support and development based on a 3-year process improvement project in a globally distributed engineering company. The company develops, delivers and supports a complex software system with tailored hardware components and unique end-customer installations. By applying the domain knowledge from operations management on lead time reduction and its multiple benefits to process performance, the workflows of globally distributed software development and multitier support processes were measured and monitored throughout the company. The results show that the global end-to-end process visibility and centrally managed reporting at all levels of the organization catalyzed a change process toward significantly better performance. Due to the new performance indicators based on lead times and their variation with fixed control procedures, the case company was able to report faster bug-fixing cycle times, improved response times and generally better customer satisfaction in its global operations. In all, lead times to implement new features and to respond to customer issues and requests were reduced by 50%.
Resumo:
Requirements-relatedissues have been found the third most important risk factor in software projects and as the biggest reason for software project failures. This is not a surprise since; requirements engineering (RE) practices have been reported deficient inmore than 75% of all; enterprises. A problem analysis on small and low maturitysoftware organizations revealed two; central reasons for not starting process improvement efforts: lack of resources and uncertainty; about process improvementeffort paybacks.; In the constructive part of the study a basic RE method, BaRE, was developed to provide an; easy to adopt way to introduce basic systematic RE practices in small and low maturity; organizations. Based on diffusion of innovations literature, thirteen desirable characteristics; were identified for the solution and the method was implemented in five key components:; requirements document template, requirements development practices, requirements; management practices, tool support for requirements management, and training.; The empirical evaluation of the BaRE method was conducted in three industrial case studies. In; this evaluation, two companies established a completely new RE infrastructure following the; suggested practices while the third company conducted continued requirements document; template development based on the provided template and used it extensively in practice. The; real benefits of the adoption of the method were visible in the companies in four to six months; from the start of the evaluation project, and the two small companies in the project completed; their improvement efforts with an input equal to about one person month. The collected dataon; the case studies indicates that the companies implemented new practices with little adaptations; and little effort. Thus it can be concluded that the constructed BaRE method is indeed easy to; adopt and it can help introduce basic systematic RE practices in small organizations.
Resumo:
Software engineering is criticized as not being engineering or 'well-developed' science at all. Software engineers seem not to know exactly how long their projects will last, what they will cost, and will the software work properly after release. Measurements have to be taken in software projects to improve this situation. It is of limited use to only collect metrics afterwards. The values of the relevant metrics have to be predicted, too. The predictions (i.e. estimates) form the basis for proper project management. One of the most painful problems in software projects is effort estimation. It has a clear and central effect on other project attributes like cost and schedule, and to product attributes like size and quality. Effort estimation can be used for several purposes. In this thesis only the effort estimation in software projects for project management purposes is discussed. There is a short introduction to the measurement issues, and some metrics relevantin estimation context are presented. Effort estimation methods are covered quite broadly. The main new contribution in this thesis is the new estimation model that has been created. It takes use of the basic concepts of Function Point Analysis, but avoids the problems and pitfalls found in the method. It is relativelyeasy to use and learn. Effort estimation accuracy has significantly improved after taking this model into use. A major innovation related to the new estimationmodel is the identified need for hierarchical software size measurement. The author of this thesis has developed a three level solution for the estimation model. All currently used size metrics are static in nature, but this new proposed metric is dynamic. It takes use of the increased understanding of the nature of the work as specification and design work proceeds. It thus 'grows up' along with software projects. The effort estimation model development is not possible without gathering and analyzing history data. However, there are many problems with data in software engineering. A major roadblock is the amount and quality of data available. This thesis shows some useful techniques that have been successful in gathering and analyzing the data needed. An estimation process is needed to ensure that methods are used in a proper way, estimates are stored, reported and analyzed properly, and they are used for project management activities. A higher mechanism called measurement framework is also introduced shortly. The purpose of the framework is to define and maintain a measurement or estimationprocess. Without a proper framework, the estimation capability of an organization declines. It requires effort even to maintain an achieved level of estimationaccuracy. Estimation results in several successive releases are analyzed. It isclearly seen that the new estimation model works and the estimation improvementactions have been successful. The calibration of the hierarchical model is a critical activity. An example is shown to shed more light on the calibration and the model itself. There are also remarks about the sensitivity of the model. Finally, an example of usage is shown.
Resumo:
Nykyään kolmeen kerrokseen perustuvat client-server –sovellukset ovat suuri kinnostuskohde sekä niiden kehittäjille etta käyttäjille. Tietotekniikan nopean kehityksen ansiosta näillä sovelluksilla on monipuolinen käyttö teollisuuden eri alueilla. Tällä hetkellä on olemassa paljon työkaluja client-server –sovellusten kehittämiseen, jotka myös tyydyttävät asiakkaiden asettamia vaatimuksia. Nämä työkalut eivät kuitenkaan mahdollista joustavaa toimintaa graafisen käyttöliittyman kanssa. Tämä diplomityö käsittelee client-server –sovellusten kehittamistä XML –kielen avulla. Tämä lähestymistapa mahdollistaa client-server –sovellusten rakentamista niin, että niiden graafinen käyttöliittymä ja ulkonäkö olisivat helposti muokattavissa ilman ohjelman ytimen uudelleenkääntämistä. Diplomityö koostuu kahdesta ostasta: teoreettisesta ja käytännöllisestä. Teoreettinen osa antaa yleisen tiedon client-server –arkkitehtuurista ja kuvailee ohjelmistotekniikan pääkohdat. Käytannöllinen osa esittää tulokset, client-server –sovellusten kehittämisteknologian kehittämislähestymistavan XML: ää käyttäen ja tuloksiin johtavat usecase– ja sekvenssidiagrammit. Käytännöllinen osa myos sisältää esimerkit toteutetuista XML-struktuureista, jotka kuvaavat client –sovellusten kuvaruutukaavakkeiden esintymisen ja serverikyselykaaviot.
Resumo:
Tässä työssä on esitetty sen ohjelmiston kehittämisen prosessi, joka on tarkoitettu annettavien palveluiden valvottavaksi käyttäen prototyyppimallia. Raportti sisältää vaatimusten, kohteisiin suunnatun analyysin ja suunnittelun, realisointiprosessien kuvauksen ja prototyypin testauksen. Ohjelmiston käyttöala – antavien palveluiden valvonta. Vaatimukset sovellukselle analysoitiin ohjelmistomarkkinoiden perusteella sekä ohjelmiston engineeringin periaatteiden mukaisesti. Ohjelmiston prototyyppi on realisoitu käyttäen asiakas-/palvelinhybridimallia sekä ralaatiokantaa. Kehitetty ohjelmisto on tarkoitettu venäläisille tietokonekerhoille, jotka erikoistuvat pelipalvelinten antamiseen.
Resumo:
Ohjelmistokehitys on monimutkainen prosessi. Yksi keskeisistä tekijöistä siinä on ohjelmistolle asetettavat vaatimukset. Näitä vaatimuksia on hyvin monenlaisia, ja eri tasoisia; toivotusta toiminnallisuudesta hyvinkin yksityiskohtaisiin vaatimuksiin. Näiden vaatimusten hallinta on myöskin hyvin monitahoista, vaikkakin se on kirjallisuudessa esitetty selkeänä prosessissa, joka on sarja toisistaan erottuviavaiheita. Työn painopiste oli näiden vaatimusten muutoksen ja valmiiseen ohjelmistoon kohdistuvan palautteen hallinnassa, ja kuinka vaatimustenhallintaohjelmisto voisi olla avuksi näissä prosesseissa. Vaatimustenhallintatyökalun käyttö ei sinällään ratkaise mitään ongelmia, mutta se suo puitteet parantaa vaatimusten hallitsemista. Työkalun käytöstä on muun muassa seuraavia etuja: vaatimusten keskitetty varastointi, käyttäjäoikeuksien määrittely koskien eri käyttäjiä ja heidän pääsyään näkemään tai muuttamaan tietoa, muutoksenhallintaprosessin hallinta, muutosten vaikutuksen analysointi ja jäljitettävyys ja pääsy tietoihin web-selaimella.
Resumo:
Työn tavoitteena oli toteuttaa tietojärjestelmä maito- ja maitotuotetilastoinnin tarpeisiin. Tietojärjestelmän tulee tukea lähes koko tilastotuotantoprosessia tallentamisesta raportointiin. Tietojärjestelmän tarpeet tulivat vaatimusmäärittelystä ja ne piti yhdistää tietohallinnon linjauksiin. Tietojärjestelmä tehdä kustannustehokkaasti tietyssä aikataulussa. Lisäksi tuli luoda käytäntöjä tuleville tilastotietojärjestelmille. Työn teoriaosan aluksi käsitellään tilastotutkimuksen perusteita ja tilastoviranomaisvaatimuksia. Tästä edetään käytännön tilastotuotantoprosessiin ja sen järjestelmävaatimuksiin. Teoriaosan loppupuoliskossa käydään läpi ohjelmistotuotantoprosessi ja tietojärjestelmän suunnittelun peruskäsitteitä. Käytännön osassa puretaan vaatimukset ja ongelma-alue. Sitten analysoidaan eri ratkaisuvaihtoehtoja. Niistä päädytään toteutusratkaisuun, jonka tuloksia tarkastellaan projektin lopputulosten ja kahden vuoden käyttökokemusten perusteella. Tietojärjestelmä toteutettiin onnistuneesti ja se mahdollistaa taloudellisen sekä laadukkaan maito- ja maitotuotetilastoinnin Suomessa.
Resumo:
Software integration is a stage in a software development process to assemble separate components to produce a single product. It is important to manage the risks involved and being able to integrate smoothly, because software cannot be released without integrating it first. Furthermore, it has been shown that the integration and testing phase can make up 40 % of the overall project costs. These issues can be mitigated by using a software engineering practice called continuous integration. This thesis work presents how continuous integration is introduced to the author's employer organisation. This includes studying how the continuous integration process works and creating the technical basis to start using the process on future projects. The implemented system supports software written in C and C++ programming languages on Linux platform, but the general concepts can be applied to any programming language and platform by selecting the appropriate tools. The results demonstrate in detail what issues need to be solved when the process is acquired in a corporate environment. Additionally, they provide an implementation and process description suitable to the organisation. The results show that continuous integration can reduce the risks involved in a software process and increase the quality of the product as well.
Resumo:
The front end of innovation is regarded as one of the most important steps in building new software products or services, and the most significant benefits in software development can be achieved through improvements in the front end activities. Problems in the front end phase have an impact on customer dissatisfaction with delivered software, and on the effectiveness of the entire software development process. When these processes are improved, the likelihood of delivering high quality software and business success increases. This thesis highlights the challenges and problems related to the early phases of software development, and provides new methods and tools for improving performance in the front end activities of software development. The theoretical framework of this study comprises two fields of research. The first section belongs to the field of innovation management, and especially to the management of the early phases of the innovation process, i.e. the front end of innovation. The second section of the framework is closely linked to the processes of software engineering, especially to the early phases of the software development process, i.e. the practice of requirements engineering. Thus, this study extends the theoretical knowledge and discloses the differences and similarities in these two fields of research. In addition, this study opens up a new strand for academic discussion by connecting these research directions. Several qualitative business research methodologies have been utilized in the individual publications to solve the research questions. The theoretical and managerial contribution of the study can be divided into three areas: 1) processes and concepts, 2) challenges and development needs, and 3) means and methods for the front end activities of software development. First, the study discloses the difference and similarities between the concepts of the front end of innovation and requirements engineering, and proposes a new framework for managing the front end of the software innovation process, bringing business and innovation perspectives into software development. Furthermore, the study discloses managerial perceptions of the similarities and differences in the concept of the front end of innovation between the software industry and the traditional industrial sector. Second, the study highlights the challenges and development needs in the front end phase of software development, especially challenges in communication, such as linguistic problems, ineffective communication channels, a communication gap between users/customers and software developers, and participation of multiple persons in software development. Third, the study proposes new group methods for improving the front end activities of software development, especially customer need assessment, and the elicitation of software requirements.
Resumo:
Software testing is one of the essential parts in software engineering process. The objective of the study was to describe software testing tools and the corresponding use. The thesis contains examples of software testing tools usage. The study was conducted as a literature study, with focus on current software testing practices and quality assurance standards. In the paper a tool classifier was employed, and testing tools presented in study were classified according to it. We found that it is difficult to distinguish current available tools by certain testing activities as many of them contain functionality that exceeds scopes of a single testing type.
Resumo:
Formal software development processes and well-defined development methodologies are nowadays seen as the definite way to produce high-quality software within time-limits and budgets. The variety of such high-level methodologies is huge ranging from rigorous process frameworks like CMMI and RUP to more lightweight agile methodologies. The need for managing this variety and the fact that practically every software development organization has its own unique set of development processes and methods have created a profession of software process engineers. Different kinds of informal and formal software process modeling languages are essential tools for process engineers. These are used to define processes in a way which allows easy management of processes, for example process dissemination, process tailoring and process enactment. The process modeling languages are usually used as a tool for process engineering where the main focus is on the processes themselves. This dissertation has a different emphasis. The dissertation analyses modern software development process modeling from the software developers’ point of view. The goal of the dissertation is to investigate whether the software process modeling and the software process models aid software developers in their day-to-day work and what are the main mechanisms for this. The focus of the work is on the Software Process Engineering Metamodel (SPEM) framework which is currently one of the most influential process modeling notations in software engineering. The research theme is elaborated through six scientific articles which represent the dissertation research done with process modeling during an approximately five year period. The research follows the classical engineering research discipline where the current situation is analyzed, a potentially better solution is developed and finally its implications are analyzed. The research applies a variety of different research techniques ranging from literature surveys to qualitative studies done amongst software practitioners. The key finding of the dissertation is that software process modeling notations and techniques are usually developed in process engineering terms. As a consequence the connection between the process models and actual development work is loose. In addition, the modeling standards like SPEM are partially incomplete when it comes to pragmatic process modeling needs, like light-weight modeling and combining pre-defined process components. This leads to a situation, where the full potential of process modeling techniques for aiding the daily development activities can not be achieved. Despite these difficulties the dissertation shows that it is possible to use modeling standards like SPEM to aid software developers in their work. The dissertation presents a light-weight modeling technique, which software development teams can use to quickly analyze their work practices in a more objective manner. The dissertation also shows how process modeling can be used to more easily compare different software development situations and to analyze their differences in a systematic way. Models also help to share this knowledge with others. A qualitative study done amongst Finnish software practitioners verifies the conclusions of other studies in the dissertation. Although processes and development methodologies are seen as an essential part of software development, the process modeling techniques are rarely used during the daily development work. However, the potential of these techniques intrigues the practitioners. As a conclusion the dissertation shows that process modeling techniques, most commonly used as tools for process engineers, can also be used as tools for organizing the daily software development work. This work presents theoretical solutions for bringing the process modeling closer to the ground-level software development activities. These theories are proven feasible by presenting several case studies where the modeling techniques are used e.g. to find differences in the work methods of the members of a software team and to share the process knowledge to a wider audience.
Resumo:
In today’s world because of the rapid advancement in the field of technology and business, the requirements are not clear, and they are changing continuously in the development process. Due to those changes in the requirements the software development becomes very difficult. Use of traditional software development methods such as waterfall method is not a good option, as the traditional software development methods are not flexible to requirements and the software can be late and over budget. For developing high quality software that satisfies the customer, the organizations can use software development methods, such as agile methods which are flexible to change requirements at any stage in the development process. The agile methods are iterative and incremental methods that can accelerate the delivery of the initial business values through the continuous planning and feedback, and there is close communication between the customer and developers. The main purpose of the current thesis is to find out the problems in traditional software development and to show how agile methods reduced those problems in software development. The study also focuses the different success factors of agile methods, the success rate of agile projects and comparison between traditional and agile software development.
Resumo:
Les sociétés modernes dépendent de plus en plus sur les systèmes informatiques et ainsi, il y a de plus en plus de pression sur les équipes de développement pour produire des logiciels de bonne qualité. Plusieurs compagnies utilisent des modèles de qualité, des suites de programmes qui analysent et évaluent la qualité d'autres programmes, mais la construction de modèles de qualité est difficile parce qu'il existe plusieurs questions qui n'ont pas été répondues dans la littérature. Nous avons étudié les pratiques de modélisation de la qualité auprès d'une grande entreprise et avons identifié les trois dimensions où une recherche additionnelle est désirable : Le support de la subjectivité de la qualité, les techniques pour faire le suivi de la qualité lors de l'évolution des logiciels, et la composition de la qualité entre différents niveaux d'abstraction. Concernant la subjectivité, nous avons proposé l'utilisation de modèles bayésiens parce qu'ils sont capables de traiter des données ambiguës. Nous avons appliqué nos modèles au problème de la détection des défauts de conception. Dans une étude de deux logiciels libres, nous avons trouvé que notre approche est supérieure aux techniques décrites dans l'état de l'art, qui sont basées sur des règles. Pour supporter l'évolution des logiciels, nous avons considéré que les scores produits par un modèle de qualité sont des signaux qui peuvent être analysés en utilisant des techniques d'exploration de données pour identifier des patrons d'évolution de la qualité. Nous avons étudié comment les défauts de conception apparaissent et disparaissent des logiciels. Un logiciel est typiquement conçu comme une hiérarchie de composants, mais les modèles de qualité ne tiennent pas compte de cette organisation. Dans la dernière partie de la dissertation, nous présentons un modèle de qualité à deux niveaux. Ces modèles ont trois parties: un modèle au niveau du composant, un modèle qui évalue l'importance de chacun des composants, et un autre qui évalue la qualité d'un composé en combinant la qualité de ses composants. L'approche a été testée sur la prédiction de classes à fort changement à partir de la qualité des méthodes. Nous avons trouvé que nos modèles à deux niveaux permettent une meilleure identification des classes à fort changement. Pour terminer, nous avons appliqué nos modèles à deux niveaux pour l'évaluation de la navigabilité des sites web à partir de la qualité des pages. Nos modèles étaient capables de distinguer entre des sites de très bonne qualité et des sites choisis aléatoirement. Au cours de la dissertation, nous présentons non seulement des problèmes théoriques et leurs solutions, mais nous avons également mené des expériences pour démontrer les avantages et les limitations de nos solutions. Nos résultats indiquent qu'on peut espérer améliorer l'état de l'art dans les trois dimensions présentées. En particulier, notre travail sur la composition de la qualité et la modélisation de l'importance est le premier à cibler ce problème. Nous croyons que nos modèles à deux niveaux sont un point de départ intéressant pour des travaux de recherche plus approfondis.
Resumo:
Cette thèse a pour but d’améliorer l’automatisation dans l’ingénierie dirigée par les modèles (MDE pour Model Driven Engineering). MDE est un paradigme qui promet de réduire la complexité du logiciel par l’utilisation intensive de modèles et des transformations automatiques entre modèles (TM). D’une façon simplifiée, dans la vision du MDE, les spécialistes utilisent plusieurs modèles pour représenter un logiciel, et ils produisent le code source en transformant automatiquement ces modèles. Conséquemment, l’automatisation est un facteur clé et un principe fondateur de MDE. En plus des TM, d’autres activités ont besoin d’automatisation, e.g. la définition des langages de modélisation et la migration de logiciels. Dans ce contexte, la contribution principale de cette thèse est de proposer une approche générale pour améliorer l’automatisation du MDE. Notre approche est basée sur la recherche méta-heuristique guidée par les exemples. Nous appliquons cette approche sur deux problèmes importants de MDE, (1) la transformation des modèles et (2) la définition précise de langages de modélisation. Pour le premier problème, nous distinguons entre la transformation dans le contexte de la migration et les transformations générales entre modèles. Dans le cas de la migration, nous proposons une méthode de regroupement logiciel (Software Clustering) basée sur une méta-heuristique guidée par des exemples de regroupement. De la même façon, pour les transformations générales, nous apprenons des transformations entre modèles en utilisant un algorithme de programmation génétique qui s’inspire des exemples des transformations passées. Pour la définition précise de langages de modélisation, nous proposons une méthode basée sur une recherche méta-heuristique, qui dérive des règles de bonne formation pour les méta-modèles, avec l’objectif de bien discriminer entre modèles valides et invalides. Les études empiriques que nous avons menées, montrent que les approches proposées obtiennent des bons résultats tant quantitatifs que qualitatifs. Ceux-ci nous permettent de conclure que l’amélioration de l’automatisation du MDE en utilisant des méthodes de recherche méta-heuristique et des exemples peut contribuer à l’adoption plus large de MDE dans l’industrie à là venir.