Дисертації з теми "QUASES software"

Ce travail vise à utiliser la spectroscopie de photoélectrons à rayons X durs (HAXPES) à l'échelle du laboratoire dans la perspective de l'analyse du fond continue inélastique (IBA) pour des applications dans le domaine de la métrologie afin de fournir des mesures d'épaisseur de matériaux technologiquement pertinents pour les mémoires et transitors de puissance. Nous cherchons à répondre au besoin d'une méthode adaptée pour les processus de contrôle en salle blanche et l'analyse de routine. Les échantillons présentés dans ce travail ont été fabriqués par des procédés préindustriels et sont représentatifs de la technologie des dispositifs réels avec des préoccupations telles que des phénomènes de diffusion et des couches et interfaces actives profondément enfouies. Dans ce travail, nous évaluons la technique HAXPES-IBA par le biais des logiciels QUASES en étudiant les paramètres libres, les contributions des opérateurs et l'incertitude du résultat de distribution en profondeur. Nous présentons une analyse autonome en accédant aux spectres de photoémission haute-énergie des éléments de chaque couche de l'échantillon, enregistrés avec un nouvel instrument HAXPES (PHI Quantes) équipé d'une source de laboratoire délivrant la radiation Cr Kα (hv = 5414,72 eV). Tout d'abord, des échantillons de référence d'épaisseur rigoureusement contrôlés (films minces Al2O3 et HfO2) ont été étudiés pour confirmer la précision de la méthode IBA par rapport à des techniques de référence hautement quantitatives. Les déterminations d'épaisseur HAXPES-IBA d'échantillons bicouches comportant une couche de surface aussi épaisse que 25 nm et une couche enterrée d'environ 2,5 nm se sont avérées être en excellent accord avec les résultats obtenus par réflectivité des rayons X (XRR) avec une incertitude de la solution IBA sub-namométrique. La nécessité de sélectionner l'énergie d'excitation en HAXPES appropriée en fonction de l'épaisseur totale des films a été démontrée grâce à l'analyse de spectres HAXPES enregistrés avec une radiation Ga Kα (hv = 9251,74 eV). Enfin, nous appliquons la méthode à des échantillons technologiques réalistes. Dans la première étude, nous présentons les résultats d'épaisseur d'une série d'échantillons de film ALD d'Al2O3 déposés sur GaN, représentatifs d'un transistor à haute mobilité électronique (HEMT) MOS à grille encastrée. Les mesures quantitatives de spectrométrie de masse d'ions secondaires (SIMS) complètent la technique IBA en confirmant le besoin d'un spectre de référence. Dans la deuxième étude, la méthode HAXPES-IBA est combinée avec la pulvérisation ionique pour confirmer l'épaisseur de recouvrement Ti/TiN dans une structure Ti/HfO2 utilisée pour la technologie de mémoire d'accès aléatoire résistive à l'oxyde (OxRRAM). Enfin, nous fournissons un résumé critique des progrès à réaliser pour une méthode HAXPES-IBA fiable et précise, entièrement intégrée dans un environnement de contrôle en ligne
This work uses lab-scale hard X-ray photoelectron spectroscopy (HAXPES) in the perspective of inelastic background analysis (IBA) for applications in the metrology field in order to provide thickness measurements of technologically relevant materials in memory and power devices. We seek to meet the need for a method adapted for inline processes and routine analysis. The samples presented in this work were fabricated by pre-industrial processes and are representative of real device technology with concerns like complex interdiffusion properties and deeply buried active layers and interfaces. In this work, we evaluate the HAXPES-IBA technique executed with QUASES software by studying the free parameters, the operator contributions, and uncertainty in the depth distribution. We present a self-contained analysis by accessing high energy photoelectron spectra of elements from each sample layer recorded with a novel lab-scale HAXPES instrument (PHI Quantes) fitted with a Cr Kα photon source (hv = 5414.72 eV). First, highly controlled reference samples of known thicknesses (Al2O3 and HfO2 thin films) were studied to confirm the accuracy of the IBA method through validation against highly quantitative reference techniques. HAXPES-IBA thickness determinations of bilayer samples with a thick overlayer up to 25 nm and a buried layer of approximately 2.5 nm were found to be in excellent agreement with results from X-ray reflectivity (XRR) with fitting uncertainty of the IBA solution in the sub-nanometer range. The need to select the appropriate HAXPES excitation energy depending on total film thickness was demonstrated thanks to complimentary HAXPES measurements recorded with Ga Kα radiation (hv = 9251.74 eV). Finally, we apply the method to realistic technological samples. In the first study, we present thickness results from a sample class of Al2O3 films deposited over GaN by atomic layer deposition (ALD), representative of a recessed gate MOS channel High Electron Mobility Transistor (HEMT). Quantitative secondary ion mass spectrometry (SIMS) measurements compliment the IBA technique by confirming need for reference spectrum. In the second study, the HAXPES-IBA method is combined with ion sputtering to confirm the Ti/TiN overlayer thickness in a Ti/HfO2-based structure used for oxide resistive random access memory (OxRRAM) technology. We provide a critical summary of advances to reach for an accurate and reliable HAXPES-IBA method fully-integrated into inline process control

Orientadores: Islene Calciolari Garcia
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação
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Resumo: Um sistema distribuído tolerante a falhas que utilize recuperação por retrocesso de estado deve selecionar os checkpoints dos seus processos que serão gravados. Além dessa seleção, definida por um protocolo de checkpointing, o sistema precisa realizar uma coleta de lixo, para eliminar os checkpoints que se tornam obsoletos à medida que a aplicação executa. Assim, na ocorrência de uma falha, a computação pode ser retrocedida para um estado consistente salvo anteriormente. Esta dissertação discute os aspectos teóricos e práticos de um sistema distribuído tolerante a falhas que utiliza protocolos de checkpointing quase-síncronos e algoritmos para a coleta de lixo e recuperação por retrocesso. Existem vários protocolos de checkpointing na literatura, e nesta dissertação foram estudados os protocolos de checkpointing quase-síncronos. Esses protocols enviam informações de controle juntamente com as mensagens da aplicação, e podem exigir a gravação de checkpoints forçados, mas não necessitam de sincronização ou troca de mensagens de controle entre os processos. Com base nesse estudo, um framework para protocolos de checkpointing quase-sincronos foi implementado numa biblioteca de troca de mensagens chamada LAM/MPI. Além disso, uma arquitetura de software para recuperação de falhas por retrocesso de estado chamada Curupira também foi estudada e implementada naquela biblioteca. O Curupira_e a primeira arquitetura de software que n~ao precisa de troca de mensagens de controle ou qualquer sincronização entre os processos na execução dos protocolos de checkpointing e de coleta de lixo
Abstract: A fault-tolerant distributed system based on rollback-recovery has to checkpoints of its processes are stored. Besides this selection, that is controlled checkpointing protocol, the system has to do garbage collection, in order to eliminate that become obsolete while the application executes. The garbage collection because checkpoints require the use of storage resources and the storage has limited capacity. So, when some fault occurs, the whole distributed be restored to a consistent global state previously stored. This dissertation practical and theoretical aspects of a fault-tolerant distributed system quasisynchronous checkpointing protocols and also garbage collection and algorithms. There are several checkpointing protocols proposed in the literature, quasisynchronous ones were studied in this dissertation. These protocols information in the application's messages and can induce forced checkpoints, need any synchronization or exchanging of control messages among on that study, a framework for quasi-synchronous checkpointing implemented in a message passing library called LAM/MPI. Moreover, a based on rollback-recovery from faults named Curupira was also implemented in that library. Curupira is the _rst software architecture exchanging of control messages or any synchronization among the execution of the checkpointing and garbage collection protocols
Mestrado
Sistemas Distribuidos
Mestre em Ciência da Computação

Dissertação (mestrado)—Universidade de Brasília, Instituto de Artes, Departamento de Artes Visuais, Programa de Pós-Graduação em Artes, 2013.
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Dissertacao de mestrado sobre praticas artisticas e educacionais entrelacadas por meio do processo de criacao audiovisual improvisada possibilitada pela tecnologia digital. As propostas pedagogicas de uso do remix - como cinema ao vivo ou como VJ (visual joquei) - sao concretizadas com o uso das ferramentas de software livre desenvolvidas pelo autor - o conjunto de programas Quase-Cinema. É tracado um paralelo entre as praticas de cinema ao vivo e software-art com o conceito de obra aberta, como observado pelos artistas Hélio Oiticica, Lygia Clark e Joseph Beuys – visões nas quais os papéis de artista, de propositor e de educador tangenciam. A pesquisa tem o foco no desenvolvimento e analise da interface do software Quase-Cinema, assim como a analise das oficinas de arte-educacao ja realizadas. Para tais esclarecimentos, sao utilizadas entrevistas realizadas presencialmente e online. O estudo tem o objetivo de identificar as potencialidades do software e suas oficinas relacionadas, com vistas em processos de expressao, capacitacao, fortalecimento e emancipacao de criadores nas cadeias criativas do audiovisual e novas midias. O processo tem como objetivo final a sensibilizacao artistica em termos de percepcao e expressao em meios digitais. _______________________________________________________________________________________ ABSTRACT
Research about artistic and educational practices woven together by improvised digital audiovisual creation enhanced by digital technologies. The pedagogical proposals centered around the use of remix on live cinema and VJ (visual jockey) practices – are made possible by the use of open source software packages (Quase-Cinema) developed by the author. A parallel is drawn between the practices of live cinema and software-art and the concept of open work of art, as seen by artists Hélio Oiticica, Lygia Clark and Joseph Beuys – visions that state the roles of artist, proponent and educator come together. The work has its focus on the development and analysis of the interface of the Quase-Cinema software, as well as a look on the art-education workshops held about the theme. Looking for these insights, interviews with users were conducted. The study had the objective of identifying the potencial of the software and its related workshops, aiming towards capacitation of creators on audiovisual and new media. The final goal is the artistic sensibilization on the terms perception and expression with digital media.

Orientadora : Profª Drª Maria do Carmo Duarte Freitas
Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Produção. Defesa: Curitiba, 12/12/2014
Inclui referências
Resumo: Trata do uso das tecnologias na educação como tema abordado de forma recorrente na área de ensino, em congressos, palestras, revistas científicas e no meio acadêmico como um todo. Tem por objetivo comparar o aprendizado usando as tecnologias aplicadas: ensino tradicional (quadro-negro) e ensino com software (Maple). O presente estudo é resultante de uma pesquisa quase experimental realizada com discentes do curso de Engenharia Civil de uma Instituição Privada de Ensino Superior de Curitiba, Estado do Paraná, Brasil, escolhida por conveniência. Fez-se a proposta de um Curso de Extensão Semi Presencial, com os conteúdos de função afim e quadrática, ao qual a matrícula foi efetuada por manifestação de interesse do discente, constituindo uma amostra não aleatória sem grupo de controle. O quase experimento foi dividido em duas fases, sendo que na primeira os alunos foram submetidos a aulas tradicionais – com o uso do quadro-negro – desenvolvendo três listas de exercícios e, ao final, uma prova. Na segunda fase, os mesmos discentes participaram das novas aulas com o uso do software Maple (escolhido por conveniência), com conteúdo idêntico ao ministrado anteriormente por meio do quadro-negro, também sendo submetidos a duas listas de exercícios e uma prova ao final. Por fim, os discentes responderam a dois questionários auto-aplicados, um no início da primeira fase e outro ao final da segunda. Com base no desempenho comparativo entre as listas e provas das fases 1 e 2, levantou-se evidências de que o uso do software contribuiu para a melhoria do desempenho bem como da compreensão do conteúdo. Destaca-se, também, que os dados quantitativos e qualitativos dos questionários demonstraram explicitamente que os discentes perceberam os benefícios da adoção do software, mesmo dentre aqueles que inicialmente apontavam a preferência pelo uso do quadro-negro. É consenso, dentre os alunos estudados, que a aula ideal é constituída pela combinação do uso do quadro-negro e do software. Palavras chave: Ensino-Aprendizagem, Ensino Superior, Maple, Software, Tecnologia.
Abstract: Deals with the use technologies in education as a subject addressed recurrently in the area of education at conferences, lectures, journals and academia as a whole. The purpose to compare the learning using the technologies applied: traditional education (blackboard) and teaching with software (Maple).This study is the result of an almost experimental research conducted with students of Civil Engineering from a private institution of Higher Education in Curitiba, Paraná State, Brazil, chosen by convenience. There was a proposed Extension Course, with the contents of affine and quadratic functions, for which registration were applied by expression of interest of the student, and therefore does not constitute a random sample and has no control group. The quasi-experiment were divided into two phases and, at the first of them, students were given traditional lessons - with the use of the blackboard - developing three lists of exercises and, at the end, a test. In the second phase, the same students attended new classes with the use of the Maple software (chosen by convenience), with identical content to that previously administered through blackboard, also being subjected to two lists of exercises and a test at the end. Finally, students responded to two self-administered questionnaires, one at the beginning of the first phase and another at the end of the second. Based on the comparative performance between the lists and tests between phases 1 and 2, evidence have risen showing that the use of the software contributed to the improvement of the performance and understanding of the content. It is noteworthy, too, that the quantitative and qualitative data from questionnaires explicitly demonstrated that students perceived the benefits of adopting the software, even among those who initially indicated a preference for the use of the blackboard. The consensus among the students studied is that the ideal class would be one that combine the use of blackboard and software. Keywords: Teaching and Learning, Higher Education, Maple, Software, Technology.

Our reliance on software has been growing fast over the past decades as the pervasive use of computer and software penetrated not only our daily life but also many critical applications. As the computational power of multi-core processors and other parallel hardware keeps increasing, concurrent software that exploit these parallel computing hardware become crucial for achieving high performance. However, developing correct and efficient concurrent software is a difficult task for programmers due to the inherent nondeterminism in their executions. As a result, concurrency related software bugs are among the most troublesome in practice and have caused severe problems in recent years. In this dissertation, I propose a series of new and fully automated methods for verifying and debugging concurrent software. They cover the detection, prevention, classification, and repair of some important types of bugs in the implementation of concurrent data structures and client-side web applications. These methods can be adopted at various stages of the software development life cycle, to help programmers write concurrent software correctly as well as efficiently.
Ph. D.

Context: Distributed software development has become a most desired way of software development. Application of agile development methodologies in distributed environments has taken a new trend in developing software due to its benefits of improved communication and collaboration. Teamwork is an important concept that agile methodologies facilitate and is one of the potential determinants of team performance which was not focused in distributed agile software development. Objectives: This research shed a light on the topic of teamwork in the context of distributed agile software development. The objectives are to identify the factors contributing teamwork of distributed agile teams along with the dependencies between the factors. And, as it is not without challenges to work with unity in a heterogeneous environment, identification of challenges related to teamwork factors of distributed agile teams along with the mitigation strategies is an another objective. Methods: A systematic literature review (SLR) was employed to identify the teamwork factors along with their dependencies and corresponding challenges and mitigation strategies of each teamwork factor from state-of-the-art literature. Quasi-gold standard method was employed as search strategy in SLR to find out the primary studies representing the objective under investigation. Further a survey was conducted with industrial practitioners working in distributed agile projects to validate the findings from state-of-the-art literature. Results: A total of 13 teamwork factors (i.e. team orientation, shared leadership, mutual performance monitoring, backup behavior, feedback, team autonomy, team learning, coordination, communication, trust, collective culture, ease of use of technology, team familiarity), a set of nine dependencies between the teamwork factors and 45 challenges and 41 mitigation strategies related to the teamwork factors were identified from state-of-the-art literature. From survey result, communication, coordination, trust and team orientation were identified as four most important teamwork factors for distributed agile teams. Out of nine dependencies, seven were supported and two were not supported by the practitioners of distributed agile projects. Additionally, nine challenges and 12 mitigation strategies were identified through survey. Conclusions: From this study, we conclude that communication is the top most important factor for successful teamwork of distributed agile teams. And, unlike its prime importance in distributed software development for getting teams work together, trust was identified with a third priority for successful teamwork of distributed agile teams. Similar to the findings of the agile teams, team autonomy was identified with least importance towards the successful teamwork of distributed agile teams. Results of dependencies show that there is need for future research to explore all the dependencies between the teamwork factors. Furthermore, there are teamwork factors with no challenges and mitigation strategies being identified in state-of-the-art literature but later, through survey it was found that practitioners are facing the challenges for that particular teamwork factor. Though, this study identified those missed challenges, due to the limited number of participants involved in the survey, we cannot conclude that these were the only challenges faced in relation to the teamwork. Hence, there is a need to have a dedicated investigation in exploring all the challenges and mitigation strategies, such that it would help the distributed agile teams in attaining the fruitful interactions between them.
H.no. 5-5-289, Prashanth Nagar, Vanasthalipuram, Hyderabad-500070, Andhra Pradesh. India

Mestrado em Gestão de Recursos Humanos
A constante evolução das tecnologias de informação e, consequentemente, dos softwares informáticos é uma realidade que cada vez mais organizações estão a adoptar para gerir os seus recursos humanos de uma forma mais eficaz. Como tal, o presente estudo analisa o caso de uma empresa portuguesa que actua no sector do retalho há mais de 65 anos e que, após uma rigorosa reestruturação organizacional, decidiu alterar drasticamente a sua ferramenta de avaliação. Neste sentido, será analisado de que modo é que a transição de uma ferramenta de avaliação em papel para uma ferramenta totalmente informatizada impactou o processo avaliativo, tal como os seus intervenientes.
The continuous evolution of information technologies and its software is something that more companies are using to manage their human resources effectively. This study is going to analyse how a Portuguese company, which has been working in the retail sector for over 65 years, decides to change the appraisal tool after a severe organizational restructure. Therefore, this study seeks to understand how the transition from an appraisal tool on paper to computer can change the appraisal process, as well as the people involved.

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Faculdade de Amparo à Ciência e Tecnologia do Estado de Pernambuco
Estudos empíricos têm se mostrado mecanismos relevantes para o avanço científico em diversas áreas, como por exemplo as Ciências Sociais e a Medicina. Tais áreas possuem considerável experiência na condução de estudos dessa natureza. Em Engenharia de Software (ES) não é diferente, pois desde a década de 1980 estudos empíricos têm sido evidenciados como um importante instrumento para o desenvolvimento da área, que é fortemente dependente de atividades humanas. Nesse cenário, é essencial ter conhecimento para conduzir os principais tipos de estudos emp´ıricos encontrados em ES, a saber: experimento controlado, quasi-experimento, survey, etnografia, pesquisa-ação e estudo de caso. A partir desse contexto, esta pesquisa visa selecionar os trabalhos mais relevantes da área que foram capazes de desenvolver algum tipo de mecanismo específico para ES que servisse de guia para os estudos empíricos citados anteriormente. Essa seleção foi realizada através de um mapeamento sistemático de estudos, o qual utilizou buscas automatizadas com a ajuda de cinco engenhos de busca de bibliotecas digitais, além de busca manual em periódicos e conferências relevantes para a área. No total, foram encontrados 7101 estudos, dos quais 23 foram identificados como trabalhos primários relevantes e serviram como fonte para coleta de evidências para responder as três perguntas de pesquisa propostas. Após a análise, conclui-se que há alguns esforços em fornecer guias específicos que apoiem a condução de estudos empíricos em ES, inclusive aproveitando experiências de outras áreas. No entanto, ainda há lacunas na área de ES empírica a serem preenchidas no que diz respeito à disponibilidade de material guia específico para ES, como por exemplo, em etnografia e pesquisa-ação, além da padronização dos procedimentos. O preenchimento de tais lacunas é essencial para fomentar a condução de tais pesquisas empíricas que são fundamentais para o desenvolvimento da ES

The aim of the thesis is the investigation of fracture-mechanics parameters on specimens made of quasi-brittle materials. The principles of two-parameter fracture mechanics are used. Couple of numerical simulations were done and their outputs are used for two main analysed specimen geometries. For simulations the finite element method software ANSYS is used. In the first part, the thesis focuses on bended specimens. The influence of different geometric parameters on fracture mechanics behaviour of cracked specimen is investigated. For model calibration the outputs of other authors are used. In the second part the specimens for modified compact-tension test (CT test) are analysed. Similar to the first part, the influence of geometric parameters of the specimen (in this case, the specimen size) on fracture mechanics parameters were investigated. The modified CT test was derived from CT test which is commonly used for metal materials testing as the suitable geometry for cement-based composite materials testing. The outputs of both parts are calibration polynomials, which are expressions obtained for different specimen geometries, giving the value of fracture mechanics parameter as the function of specimen geometry. As the example, calibration curves are used to obtain fracture toughness of tested material using the outputs from recent experiment.

This paper addresses the question formulation “Is it possible to implement automated testing in an existing client-server game in order to pinpoint faults and achieve credibility to tests?” The gaming industry’s goal, in most cases, is to release games that appeal to both their financial goals and the enjoyment factor of the players. In order to fulfill these goals, the game will need to function properly and the process to assure this is testing the game to find possible faults. This process is time and cost consuming in an exponential rate in accordance to game extensiveness, which makes this problem a very important decision in the process of development. The problem is most commonly tackled by using massive manual testing session, called alpha or beta sessions. In these session the game is at an early stage of development and gets released to a set player base to test and report issues encountered. We believe that the process of testing games could be more effective by utilizing automated testing. This thesis will investigate the possibilities to our claim. The result is a visual representation of the tests we managed to apply, while focusing on the client-server connectivity of Quake 3 and a graph of measurements for our improvised fault localization. This paper describes a solution in form of automated tests within a existing client-server game and a start to what could be early stages of a pattern obtained throughout this project.

Abstract Modern software development must adapt to demanding schedules while keeping the software at a high level of quality. Agile software development has been adopted in recent years to meet such a need. Test-driven development (TDD) is one practice that has arisen within the agile software development movement that leverages unit tests to develop software in incremental cycles. TDD supporters claim that the practice increases the productivity of the practitioners who employ it, as well as the internal and external quality of the software they develop. In order to validate or refute such claims, the software engineering research community has studied TDD for the last decade; the results of the empirical studies on the effects of TDD have been mostly inconclusive. This dissertation has studied two factors that may impact the manifestation of the claimed effects of TDD on software’s external quality and developers’ productivity: the developers’ conformance to the process (i.e., their ability to follow TDD) and their skills. The research was performed in four phases. In the first phase, the literature was reviewed to identify a set of factors that have been considered to affect TDD. In the second phase, two experiments were executed within academia. A total of 77 students at the University of Oulu, took part in the studies. These experiments investigated the quality of the software, as well as the subject’s productivity with respect to their programming and testing skills. A follow-up study, using data collected during the second experiment, explored the relation between the quality, productivity and the subjects’ process conformance. In the third phase, four industrial experiments, involving 30 professional, were performed. Process conformance and skills were investigated in relation to the TDD’s effects on external quality and productivity. The fourth phase synthesized the evidence gathered in the two previous phases. The results show that TDD is not associated with improvements in external quality, or developers’ productivity. Further, improvements in both external quality and productivity are associated with skills, rather than with the process, at least in the case of professional developers. Hence, process conformance has a negligible impact. The productivity of novice developers, on the other hand, can benefit from the test-first approach promoted by TDD
Tiivistelmä Modernin ohjelmistokehityksen täytyy mukautua haastaviin aikatauluihin säilyttäen ohjelmistojen korkea laatu. Ketterä ohjelmistokehitys on viime vuosina omaksuttu tähän tarpeeseen ja suuntauksessa on saanut alkunsa testivetoisen kehityksen käytäntö, joka hyödyntää yksikkötestausta ohjelmiston inkrementaalisessa, syklisessä kehityksessä. Testivetoisen kehityksen puolestapuhujat väittävät tämän käytännön lisäävän ohjelmistokehittäjien tuottavuutta sekä ohjelmiston sisäistä ja ulkoista laatua. Ohjelmistotuotannon tutkimusyhteisö on tutkinut testivetoista kehitystä viimeisen vuosikymmenen aikana vahvistaakseen tai kumotakseen nämä väitteet. Empiiriset tutkimukset testivetoisen kehityksen vaikutuksista ohjelmistotuotantoon ovat suurelta osin tuloksettomia. Tämä väitöstyö tutkii kahta tekijää, jotka voivat vaikuttaa testivetoisen kehityksen väitettyjen vaikutusten ilmentymiseen ohjelmiston ulkoisena laatuna ja ohjelmistokehittäjien tuottavuutena: ohjelmistokehittäjien taitoja ja prosessin mukaista toimintaa. Tutkimus toteutettiin neljässä vaiheessa. Ensimmäisessä vaiheessa tehtiin kirjallisuuskatsaus, jolla selvitettiin tekijöitä, joiden on katsottu vaikuttavan testivetoiseen kehitykseen. Toisessa vaiheessa tehtiin Oulun yliopistolla kaksi koetta, joihin osallistui kaikkiaan 77 opiskelijaa. Kokeissa tutkittiin ohjelmiston laadun ja osallistujien tuottavuuden suhdetta heidän ohjelmointi- ja testaustaitoihinsa. Toisen kokeen aikana kerättyä aineistoa hyödynnettiin jatkotutkimuksessa, jossa tarkasteltiin laadun, tuottavuuden ja prosessin mukaisen toiminnan suhdetta. Kolmannessa vaiheessa tehtiin neljä koetta, joihin osallistui 30 ohjelmistoalan ammattilaista. Prosessin mukaista toimintaa ja taitoja tutkittiin suhteessa testivetoisen kehityksen vaikutuksiin ohjelmiston ulkoiseen laatuun ja tuottavuuteen. Neljännessä vaiheessa syntetisoitiin kahden edellisen vaiheen löydökset. Tulokset osoittavat, ettei testivetoinen kehitys liity ulkoisen laadun parantumiseen eikä ohjelmistokehittäjien tuottavuuteen. Parannukset laadussa ja tuottavuudessa liittyvät ennemmin taitoihin kuin prosessiin, ainakin ohjelmistokehityksen ammattilaisten kohdalla. Näin ollen prosessin mukaisella toiminnalla on vähäpätöinen vaikutus. Toisaalta testivetoisen kehityksen suosiman test-first-menettelytavan hyödyntäminen voi edistää aloittelevien ohjelmistokehittäjien tuottavuutta

Im Bereich der industriellen Metallurgie und Kristallzüchtung treten bei zahlreichen Anwendungen, wo magnetische Wechselfelder zur induktiven Beeinflussung von leitfähigen Werkstoffen eingesetzt werden, auch Strömungen mit freier Oberfläche auf. Das Anwendungsspektrum reicht dabei vom einfachen Aufschmelzen eines Metalls in einem offenen Tiegel bis hin zur vollständigen Levitation. Auch der sogenannte RGS-Prozess, ein substratbasiertes Kristallisationsverfahren zur Herstellung siliziumbasierter Dünnschichtmaterialien, ist dafür ein Beispiel. Um bei solchen Prozessen die Interaktion von Magnetfeld und Strömung zu untersuchen, ist die numerische Simulationen ein wertvolles Hilfsmittel. Für beliebige dreidimensionale Probleme werden entsprechende Berechnungen bisher durch eine externe Kopplung kommerzieller Programme realisiert, die für Magnetfeld und Strömung jeweils unterschiedliche numerische Techniken nutzen. Diese Vorgehensweise ist jedoch im Allgemeinen mit unnötigem Rechenaufwand verbunden. In dieser Arbeit wird ein neu entwickelter Methodenapparat auf Basis der FVM vorgestellt, mit welchem sich diese Art von Berechnungen effizient durchführen lassen. Mit der Implementierung dieser Methoden in foam-extend, einer erweiterten Version der quelloffenen Software OpenFOAM, ist daraus ein leistungsfähiges Werkzeug in Form einer freien Simulationsplattform entstanden, welches sich durch einen modularen Aufbau leicht erweitern lässt. Mit dieser Plattform wurden in foam-extend auch erstmalig dreidimensionale Induktionsprozesse im Frequenzraum gelöst.

Im Bereich der industriellen Metallurgie und Kristallzüchtung treten bei zahlreichen Anwendungen, wo magnetische Wechselfelder zur induktiven Beeinflussung von leitfähigen Werkstoffen eingesetzt werden, auch Strömungen mit freier Oberfläche auf. Das Anwendungsspektrum reicht dabei vom einfachen Aufschmelzen eines Metalls in einem offenen Tiegel bis hin zur vollständigen Levitation. Auch der sogenannte RGS-Prozess, ein substratbasiertes Kristallisationsverfahren zur Herstellung siliziumbasierter Dünnschichtmaterialien, ist dafür ein Beispiel. Um bei solchen Prozessen die Interaktion von Magnetfeld und Strömung zu untersuchen, ist die numerische Simulationen ein wertvolles Hilfsmittel. Für beliebige dreidimensionale Probleme werden entsprechende Berechnungen bisher durch eine externe Kopplung kommerzieller Programme realisiert, die für Magnetfeld und Strömung jeweils unterschiedliche numerische Techniken nutzen. Diese Vorgehensweise ist jedoch im Allgemeinen mit unnötigem Rechenaufwand verbunden. In dieser Arbeit wird ein neu entwickelter Methodenapparat auf Basis der FVM vorgestellt, mit welchem sich diese Art von Berechnungen effizient durchführen lassen. Mit der Implementierung dieser Methoden in foam-extend, einer erweiterten Version der quelloffenen Software OpenFOAM, ist daraus ein leistungsfähiges Werkzeug in Form einer freien Simulationsplattform entstanden, welches sich durch einen modularen Aufbau leicht erweitern lässt. Mit dieser Plattform wurden in foam-extend auch erstmalig dreidimensionale Induktionsprozesse im Frequenzraum gelöst.