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Mobila hybridapplikationers prestanda : En experimentell studie / The performance of mobile hybrid applications : An experimental studyNilsson, Elias, Lagerqvist, Alexander January 2015 (has links)
Syfte – Studiens syfte är att undersöka hybridapplikationers prestanda i olika situationer för att ta reda på varför de upplevs som långsamma. För att uppnå syftet besvaras följande frågeställningar: Hur presterar hybridapplikationer jämfört med nativapplikationer beräkningsmässigt Är JavaScript-biblioteken anledningen till hybridapplikationers sämre prestanda, och vilket av de bibliotek som undersöks är det mest lämpade för bästa prestanda? Kan hybridapplikationer hantera stora datamängder med IndexedDB utan att bli oresponsiva? Metod – Studien använder sig av en experimentell forskningsmetod där hypoteser och förutsägelser formuleras och sedan testas för att besvara frågeställningarna. Resultat – Resultatet från studien visar att prestandan för mobila hybrid-applikationer är i de flesta fall, vid utförande av samma uppgift, underlägsen den för dess motsvarande nativapplikationer. Resultaten visar även att prestandan påverkas av vilket JavaScript-bibliotek som används men att biblioteken inte är anledningen till hybridapplikationers långsamma prestanda. Vidare visar resultaten att hybridapplikationer kan hantera stora datamängder utan att bli oresponsiva. Implikationer – Studien bidrar till att bredda den kunskapsbas som finns om hybridapplikationers prestanda och ger framtida forskning referensdata att bygga vidare på. Studien påvisar dessutom att hybridapplikationer fortfarande är ett alternativ, i synnerhet för företag som vill spara tid och som ej kräver applikationer som utför tunga beräkningar. Begränsningar – Användandet av applikationer som sannolikt inte förekommer i ett verklighetstroget scenario bidrog till resultat som inte har stor relevans inom de användningsområden som finns för hybridapplikationer. / Purpose – The purpose of this thesis is to examine the performance of hybrid mobile applications in different situations to find out why they are perceived as slow. To fulfill the purpose, the following research questions will be answered: How do hybrid applications perform compared to native applications computationally? Are the JavaScript-libraries the reason behind the slower performance of hybrid applications, and which one of the libraries that are examined is most suitable for the best performance? Can hybrid applications manage large amounts of data with IndexedDB without getting unresponsive? Method – The study uses an experimental research method where hypotheses and predictions are formulated and later tested to answer the research questions. Results – The results show that the performance of mobile hybrid applications are in most cases, when performing the same task, inferior to that of corresponding native applications. The results also show that the performance is affected by which JavaScript-library that is being used, but that it is not the main reason for hybrid applications poor performance. They also show that hybrid applications can manage large amounts of data without becoming unresponsive. Implications – The study contributes to broadening the knowledge available on the performance of mobile hybrid applications and provides future research with reference data to build upon. The study also demonstrate that hybrid applications still is an alternative, especially for enterprises who want to save time and does not demand applications that perform heavy computations. Research limitations – The use of applications that most likely would not occur in a realistic scenario contributed with results that have little relevance in the areas of use that exists for hybrid applications.
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Taking architecture and compiler into account in formal proofs of numerical programsNguyen, Thi Minh Tuyen 11 June 2012 (has links) (PDF)
On some recently developed architectures, a numerical program may give different answers depending on the execution hardware and the compilation. These discrepancies of the results come from the fact that each floating-point computation is calculated with different precisions. The goal of this thesis is to formally prove properties about numerical programs while taking the architecture and the compiler into account. In order to do that, we propose two different approaches. The first approach is to prove properties of floating-point programs that are true for multiple architectures and compilers. This approach states the rounding error of each floating-point computation whatever the environment and the compiler choices. It is implemented in the Frama-C platform for static analysis of C code. The second approach is to prove behavioral properties of numerical programs by analyzing their compiled assembly code. We focus on the issues and traps that may arise on floating-point computations. Direct analysis of the assembly code allows us to take into account architecture- or compiler-dependent features such as the possible use of extended precision registers. It is implemented above the Why platform for deductive verification
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Computing-Based Testing: conceptual model, implementations and experiments extending IMS QTI.Santos Rodríguez, Patrícia 20 December 2011 (has links)
The use of objective tests in Technology Enhanced Learning (TEL) is
based on the application of computers to support automatic assessment.
Current research in this domain is mainly focused on the design of new
question-items, being IMS Question and Test Interoperability (QTI) the
recognized de-facto standard. This thesis claims that the domain can be
extended with the design of advanced test-scenarios that integrate new
interactive contexts for the visualization of question-items and tests, and
that consider different types of devices and technologies that enable
diverse activity settings. In this context, the dissertation proposes to term
the domain as Computing-Based Testing (CBT) instead of Computer-
Based Testing because it captures better the new technological support
possibilities for testing. Advanced CBT scenarios can increase teachers’
choices in the design of more appropriate tests for their subject areas,
enabling the assessment of higher-order skills.
With the aim of modelling an advanced CBT domain that extends the
current possibilities of QTI and related work, this thesis provides a set of
contributions around three objectives. The first objective deals with
proposing a Conceptual Model for the CBT domain considering three
main dimensions: the Question-item, the Test and the Activity. To tackle
this objective, the thesis presents, on the one hand, a framework to assist
in the categorization and design of advanced CBT scenarios and, on the
other hand, two models that suggest elements for technologically
representing the Test and Question-item dimensions. The models are
platform-independent models (PIM) that extend QTI in order to support
advanced CBT. Besides, the use of patterns is proposed to complement
the modelling of the domain. The second objective seeks to show the
relevance, value and applicability of the CBT Conceptual Model through
exemplary challenging scenarios and case studies in authentic settings. To
this end, the dissertation evaluates the design and implementation of a set
of CBT systems and experiments. All the experiments use the proposed
CBT Conceptual Model for designing an advanced CBT scenario. For
each case the CBT-PIMs serve as the basis for developing a particular
CBT-PSM and system. The evaluation results show that the
implementations foster educational benefits, enable the assessment of
higher-order skills and enhance the students’ motivation. Finally, the third
objective is devoted to propose extension paths for QTI. The collection of
models proposed in the thesis suggests different extension directions for
QTI so as to enable the implementation of advanced questions, tests and
activities. The proposed systems and scenarios also represent reference
implementation and good practices of the proposed extension paths. / El uso de test de corrección automática, en el Aprendizaje Apoyado por
Tecnologías de la Información y las Comunicaciones, se basa en el uso de
ordenadores. Las propuestas actuales se centran en el diseño de nuevas
preguntas, siendo IMS Question and Test Interoperability (QTI) el
estándar de-facto. La tesis propone que este dominio puede ser extendido
con el diseño de escenarios de test avanzados que integren nuevos
contextos de interacción para la visualización de preguntas y tests, y que
consideren la aplicación de diversos dispositivos tecnológicos para
permitir diversos tipos de actividades. En este contexto se propone usar el
término inglés Computing-Based Testing (CBT) para referirse al dominio,
en vez de usar el término Computer-Based Testing, enfatizando el papel
de la tecnología para la evaluación basada en test. Los escenarios CBT
avanzados pueden aumentar la posibilidad de que los profesores puedan
diseñar test más adecuados para sus asignaturas, permitiendo la
evaluación de habilidades de alto nivel.
Con el reto principal de modelar el dominio del CBT extendiendo las
posibilidades actuales de QTI y las aproximaciones actuales, esta tesis
proporciona un conjunto de contribuciones relacionadas con tres
objetivos. El primer objetivo de la tesis es proponer un Modelo
Conceptual definiendo y relacionando tres dimensiones: Pregunta, Test y
Actividad. Por una parte, se propone un marco como guía en la
categorización y diseño de escenarios CBT. Además, se proponen dos
modelos que indican los elementos para la representación tecnológica de
preguntas y test. Estos modelos son independientes de plataforma (PIM)
que extienden QTI formulando los elementos que permiten implementar
escenarios CBT avanzados. Además, se propone el uso de patrones como
complemento en el modelado del dominio. El segundo objetivo trata de
mostrar la relevancia y aplicabilidad de las contribuciones a través de
escenarios y casos de estudio representativos en contextos reales. Para
ello, se evalúa el diseño e implementación de un conjunto de
experimentos y sistemas. En todos los experimentos se utiliza el Modelo
Conceptual para diseñar escenarios CBT avanzados. Para cada caso los
CBT-PIMs sirven como base para desarrollar modelos específicos de
plataforma (CBT-PSMs) y sistemas asociados. La evaluación muestra que
las implementaciones resultantes tienen beneficios educativos positivos,
permitiendo la evaluación de habilidades de alto nivel y mejorando la
motivación de los estudiantes. Finalmente, el tercer objetivo se centra en
proponer vías de extensión para QTI. La colección de modelos propuestos
sugiere diferentes direcciones de extensión de QTI para la
implementación de preguntas, tests y actividades avanzados. Los
escenarios y sistemas llevados a cabo representan implementaciones de
referencia y buenas prácticas para las vías de extensión propuestas.
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Gera??o procedural de cen?rios orientada a objetivosDuarte, Philip Michel 26 February 2012 (has links)
Made available in DSpace on 2014-12-17T15:48:00Z (GMT). No. of bitstreams: 1
PhilipMD_DISSERT.pdf: 3999230 bytes, checksum: fd3b6c186bc10448c63b511e10e6017e (MD5)
Previous issue date: 2012-02-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The game industry has been experiencing a consistent increase in production costs of games lately. Part of this increase refers to the current trend of having bigger, more interactive and replayable environments. This trend translates to an
increase in both team size and development time, which makes game development a even more risky investment and may reduce innovation in the area. As a possible solution to this problem, the scientific community is focusing on the generation
of procedural content and, more specifically, on procedurally generated levels. Given the great diversity and complexity of games, most works choose to deal with a specific genre, platform games being one of the most studied. This work
aims at proposing a procedural level generation method for platform/adventure games, a fairly more complex genre than most classic platformers which so far has not been the subject of study from other works. The level generation process was
divided in two steps, planning and viusal generation, respectively responsible for generating a compact representation of the level and determining its view. The planning stage was divided in game design and level design, and uses a goaloriented process to output a set of rooms. The visual generation step receives a
set of rooms and fills its interior with the appropriate parts of previously authored geometry / Recentemente a ind?stria de jogos vem experimentando um aumento consistente nos custos de produ??o de jogos. Parte deste aumento ? referente ? tend?ncia atual de se ter ambientes cada vez maiores, mais interativos e rejog?veis.
Esta tend?ncia se reflete num aumento das equipes e do tempo de desenvolvimento, o que torna o desenvolvimento de jogos um investimento de risco e pode reduzir a inova??o na ?rea. Como uma poss?vel solu??o para este problema, a comunidade cient?fica vem apostando na gera??o procedural de conte?do e, mais especificamente, na gera??o procedural de cen?rios. Dada a grande diversidade e complexidade dos jogos, a maioria dos trabalhos opta por trabalhar em g?neros espec?ficos, sendo os jogos de plataforma um dos g?neros mais estudados.
Este trabalho prop?e um m?todo de gera??o de cen?rios para jogos de plataforma/ aventura, um g?nero mais complexo que jogos de plataforma cl?ssicos e que at? o momento n?o foi alvo de estudo de outros trabalhos. Dividimos a gera??o de cen?rios em etapas de planejamento e gera??o visual, respons?veis
respectivamente por gerar proceduralmente uma representa??o compacta de cen?rio e determinar sua visualiza??o. A etapa de planejamento se divide em game design e level design, e se utiliza de um processo orientado a objetivos para produzir
como sa?da um conjunto de salas. A etapa de gera??o visual recebe um conjunto de salas e preenche seus interiores com partes adequadas de geometria previamente constru?das
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A distributed service delivery platform for automotive environments : enhancing communication capabilities of an M2M service platform for automotive applicationGlaab, Markus January 2018 (has links)
The automotive domain is changing. On the way to more convenient, safe, and efficient vehicles, the role of electronic controllers and particularly software has increased significantly for many years, and vehicles have become software-intensive systems. Furthermore, vehicles are connected to the Internet to enable Advanced Driver Assistance Systems and enhanced In-Vehicle Infotainment functionalities. This widens the automotive software and system landscape beyond the physical vehicle boundaries to presently include as well external backend servers in the cloud. Moreover, the connectivity facilitates new kinds of distributed functionalities, making the vehicle a part of an Intelligent Transportation System (ITS) and thus an important example for a future Internet of Things (IoT). Manufacturers, however, are confronted with the challenging task of integrating these ever-increasing range of functionalities with heterogeneous or even contradictory requirements into a homogenous overall system. This requires new software platforms and architectural approaches. In this regard, the connectivity to fixed side backend systems not only introduces additional challenges, but also enables new approaches for addressing them. The vehicle-to-backend approaches currently emerging are dominated by proprietary solutions, which is in clear contradiction to the requirements of ITS scenarios which call for interoperability within the broad scope of vehicles and manufacturers. Therefore, this research aims at the development and propagation of a new concept of a universal distributed Automotive Service Delivery Platform (ASDP), as enabler for future automotive functionalities, not limited to ITS applications. Since Machine-to-Machine communication (M2M) is considered as a primary building block for the IoT, emergent standards such as the oneM2M service platform are selected as the initial architectural hypothesis for the realisation of an ASDP. Accordingly, this project describes a oneM2M-based ASDP as a reference configuration of the oneM2M service platform for automotive environments. In the research, the general applicability of the oneM2M service platform for the proposed ASDP is shown. However, the research also identifies shortcomings of the current oneM2M platform with respect to the capabilities needed for efficient communication and data exchange policies. It is pointed out that, for example, distributed traffic efficiency or vehicle maintenance functionalities are not efficiently treated by the standard. This may also have negative privacy impacts. Following this analysis, this research proposes novel enhancements to the oneM2M service platform, such as application-data-dependent criteria for data exchange and policy aggregation. The feasibility and advancements of the newly proposed approach are evaluated by means of proof-of-concept implementation and experiments with selected automotive scenarios. The results show the benefits of the proposed enhancements for a oneM2M-based ASDP, without neglecting to indicate their advantages for other domains of the oneM2M landscape where they could be applied as well.
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[en] AN EMPIRICAL ANALYSIS AND PROPOSAL OF A NEW MODEL OF LOGISTIC PLANNING FOR CARGO SHIPPING TO PETROBRAS FIELDS IN SANTOS BASIN / [pt] ANÁLISE EMPÍRICA E PROPOSTA DE NOVO MODELO DE PLANEJAMENTO LOGÍSTICO DO TRANSPORTE MARÍTIMO DE CARGAS PARA OS CAMPOS DA BACIA DE SANTOS DA PETROBRASDIEGO AGRA MENDES 31 August 2018 (has links)
[pt] As operações de EeP na Bacia de Santos sempre ficaram em segundo plano quando comparadas com a Bacia de Campos, berço das gigantescas descobertas petrolíferas dos últimos 40 anos. Porém, com a descoberta do pré-sal, mais presente na Bacia de Santos, essa hegemonia da Bacia de Campos está aos poucos diminuindo, tendo a produção do pré-sal ultrapassado pela primeira vez a do póssal em junho de 2017. Com isso, torna-se imprescindível o aprimoramento da operação para atender a essa nova demanda. Junto com essa nova descoberta, a grave crise que a indústria do petróleo tem vivido desde 2014 com a alta queda no preço do barril, mais intensificada ainda no Brasil devido ao aumento do dólar, trouxe um novo foco para a diminuição do custo de extração, incluindo aí a diminuição de custos logísticos. Na Petrobras, a grande parte da produção de petróleo vem de água profundas e as unidades marítimas necessitam de suprimentos em volume considerável e tempo hábil para realizar suas operações. O elo final da cadeia logística para atendimento às unidades marítimas são as embarcações e elas representam cerca de 70 por cento dos custos logísticos. Nesse estudo, as diferentes metodologias de atendimento marítimo para transporte de cargas utilizadas nos últimos anos, tanto na Bacia de Campos quanto na de Santos, foram analisadas empiricamente e foram encontrados alguns pontos passíveis de melhoria. Uma
possibilidade de redução de frota foi identificada e uma metodologia para realizar essa redução foi proposta. A metodologia se baseia em uma nova forma de formação de clusters, reduzindo o tempo total de navegação das embarcações, e um novo ordenamento portuário, de tal forma que uma mesma embarcação possa realizar mais serviços durante a semana, gerando assim menor necessidade de frota.
A nova metodologia completa foi implantada em janeiro de 2018, gerando inicialmente uma diminuição de 20 por cento da frota de transporte de carga na Bacia de Santos. / [en] EeP operations in the Santos Basin have always been left in second plan when compared to the Campos Basin, the cradle of the gigantic oil discoveries of the last 40 years. However, with the discovery of the pre-salt, more present in the Santos Basin, this hegemony of the Campos Basin is gradually diminishing, with
the production of the pre-salt having surpassed for the first time the one of the postsalt in June of 2017. With this, it is essential to improve the operation to meet this new demand. Along with this new discovery, the severe crisis that the oil industry has experienced since 2014 with the sharp fall in the price of the barrel, more intensified in Brazil due to the increase of the dollar, brought a new focus in reducing the cost of extraction, including the reduction of logistics costs. At Petrobras, most of the oil production comes from deep water and the maritime units need supplies in considerable volume and on time to carry out their operations. The final link of the logistics chain to serve this maritime units are vessels and they represent about 70 percent of logistics costs. In this study, the different maritime service policies for deck cargo transport used in recent years, both in the Campos Basin and Santos Basin, were analyzed empirically and some improvement points were found. The feasibility of reducing the fleet was identified and a methodology to accomplish this reduction was proposed. The methodology is based on a new form of clusters formation, reducing the total vessels navigation time, and a new berth scheduling, in such a way that the same vessel can perform more services during the week, thus generating less need of fleet. The complete new methodology was implemented in January 2018, initially generating a 20 percent decrease in the cargo transport fleet in the Santos Basin.
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Model driven engineering methodology for design space exploration of embedded systems / Metodologia de engenharia dirigida por modelos para exploração do espaço de projeto de sistemas embarcados / Modellgetriebene entwicklungsmethodik für die entwurfsraumexploration von eingebetteten systemeOliveira, Marcio Ferreira da Silva January 2013 (has links)
Heutzutage sind wir von Geräten umgeben, die sowohl Hardware wie auch Software- Komponenten beinhalten. Diese Geräte unterstützen ein breites Spektrum an verschiedenen Domänen, so zum Beispiel Telekommunikation, Luftfahrt, Automobil und andere. Derartige Systeme sind überall aufzufinden und werden als Eingebettete Systeme bezeichnet, da sie zur Informationsverarbeitung in andere Produkte eingebettet werden, wobei die Informationsverarbeitung des eingebetteten Systems jedoch nicht die bezeichnende Funktion des Produkts ist. Die ständig zunehmende Komplexität moderner eingebettete Systeme erfordert die Verwendung von mehreren Komponenten um die Funktionen von einem einzelnen System zu implementieren. Eine solche Steigerung der Funktionalität führt jedoch ebenfalls zu einem Wachstum in der Entwurfs-Komplexität, die korrekt und effizient beherrscht werden muss. Neben hohen Anforderungen bezüglich Leistungsaufnahme, Performanz und Kosten hat auch Time-to-Market-Anforderungen großen Einfluss auf den Entwurf von Eingebetteten Systemen. Design Space Exploration (DSE) beschreibt die systematische Erzeugung und Auswertung von Entwurfs-Alternativen, um die Systemleistung zu optimieren und den gestellten Anforderungen an das System zu genügen. Bei der Entwicklung von Eingebetteten Systemen, speziell beim Platform-Based Design (PBD) führt die zunehmende Anzahl von Design-Entscheidungen auf mehreren Abstraktionsebenen zu einer Explosion der möglichen Kombinationen von Alternativen, was auch für aktuelle DSE Methoden eine Herausforderung darstellt. Jedoch vermag üblicherweise nur eine begrenzte Anzahl von Entwurfs-Alternativen die zusätzlich formulierten nicht-funktionalen Anforderungen zu erfüllen. Darüber hinaus beeinflusst jede Entwurfs- Entscheidung weitere Entscheidungen und damit die resultierenden Systemeigenschaften. Somit existieren Abhängigkeiten zwischen Entwurfs-Entscheidungen und deren Reihenfolge auf dem Weg zur Implementierung des Systems. Zudem gilt es zwischen einer spezifischen Heuristik für eine bestimmte DSE, welche zu verbesserten Optimierungsresultaten führt, sowie globalen Verfahren, welche ihrerseits zur Flexibilität hinsichtlich der Anwendbarkeit bei verschiedenen DSE Szenarien beitragen, abzuwägen. Um die genannten Herausforderungen zu lösen wird eine Modellgetriebene Entwicklung (englisch Model-Driven Engineering, kurz MDE) Methodik für DSE vorgeschlagen. Für diese Methodik wird ein DSE-Domain-Metamodell eingeführt um relevante DSEKonzepte wie Entwurfsraum, Entwurfs-Alternativen, Auswertungs- und Bewertungsverfahren, Einschränkungen und andere abzubilden. Darüber hinaus modelliert das Metamodell verschiedenen DSE-Frage- stellungen, was zur Verbesserung der Flexibilität der vorgeschlagenen Methodik beiträgt. Zur Umsetzung von DSE-Regeln, welche zur Steuerung, Einschränkung und Generierung der Ent- wurfs-Alternativen genutzt werden, finden Modell-zu-Modell-Transformationen Anwendung. Durch die Fokussierung auf die Zuordnung zwischen den Schichten in einem PBDAnsatz wird eine neuartige Entwurfsraumabstraktion eingeführt, um multiple Entwurfsentscheidungen als singuläres DSE Problem zu repräsentieren. Diese auf dem Categorial Graph Product aufbauende Abstraktion entkoppelt den Explorations-Algorithmus vom Entwurfsraum und ist für Umsetzung in automatisierte Werkzeugketten gut geeignet. Basierend auf dieser Abstraktion profitiert die DSE-Methode durch die eingeführte MDEMethodik als solche und ermöglicht nunmehr neue Optimierungsmöglichkeiten sowie die Verbesserung der Integration von DSE in Entwicklungsprozesse und die Spezifikation von DSE-Szenarien. / Atualmente dispositivos contendo hardware e software são encontrados em todos os lugares. Estes dispositivos prestam suporte a uma varieadade de domínios, como telecomunicações, automotivo e outros. Eles são chamados “sistemas embarcados”, pois são sistemas de processamento montados dentro de produtos, cujo sistema de processamento não faz parte da funcionalidade principal do produto. O acréscimo de funções nestes sistemas implica no aumento da complexidade de seu projeto, o qual deve ser adequadamente gerenciado, pois além de requisitos rigorosos em relação à dissipação de potência, desempenho e custos, a pressão sobre o prazo para introdução de um produto no mercado também dificulta seu projeto. Exploração do espaço de projeto (DSE) é a atividade sistemática de gerar e avaliar alternativas de projetos, com o objetivo de otimizar suas propriedades. No desenvolvimento de sistemas embarcados, especialmente em Projeto Baseado em Plataformas (PBD), metodologias de DSE atuais são desafiadas pelo crescimento do número de decisões de projeto, o qual implica na explosão da combinação de alternativas. Porém, somente algumas destas resultam em projetos que atedem os requisitos nãofuncionais. Além disso, as decisões influenciam umas às outras, de forma que a ordem em que estas são tomadas alteram a implementação final do sistema. Outro desafio é o balanço entre flexibilidade da metodologia e seu desempenho, pois métodos globais de otimização são flexíveis, mas apresentam baixo desempenho. Já heurísticas especialmente desenvolvidas para o cenário de DSE em questão apresentam melhor desempenho, porém dificilmente são aplicáveis a diferentes cenários. Com o intuito de superar os desafios é proposta uma metodologia de projeto dirigido por modelos (MDE) adquada para DSE. Um metamodelo do domínio de DSE é definido para representar conceitos como espaço de projeto, métodos de avaliação e restrições. O metamodelo também representa diferentes problemas de DSE aprimorando a flexibilidade da metodologia. Regras de transformações de modelos implementam as regras de DSE, as quais são utilizadas para restringir e guiar a geração de projetos alternativos. Restringindo-se ao mapeamento entre camadas no PBD é proposta uma abstração para representar o espaço de projeto. Ela representa múltiplas decisões de projeto envolvidas no mapeamento como um único problema de DSE. Esta representação é adequada para a implementação em ferramentas automática de DSE e pode beneficiar o processo de DSE com uma abordagem de MDE, aprimorando a especificação de cenários de DSE e sua integração no processo de desenvolvimento. / Nowadays we are surrounded by devices containing hardware and software components. These devices support a wide spectrum of different domains, such as telecommunication, avionics, automobile, and others. They are found anywhere, and so they are called Embedded Systems, as they are information processing systems embedded into enclosing products, where the processing system is not the main functionality of the product. The ever growing complexity in modern embedded systems requires the utilization of more components to implement the functions of a single system. Such an increasing functionality leads to a growth in the design complexity, which must be managed properly, because besides stringent requirements regarding power, performance and cost, also time-to-market hinders the design of embedded systems. Design Space Exploration (DSE) is the systematic generation and evaluation of design alternatives, in order to optimize system properties and fulfill requirements. In embedded system development, specifically in Platform-Based Design (PBD), current DSE methodologies are challenged by the increasing number of design decisions at multiple abstraction levels, which leads to an explosion of combination of alternatives. However, only a reduced number of these alternatives leads to feasible designs, which fulfill non-functional requirements. Moreover, each design decision influences subsequent decisions and system properties, hence there are inter-dependencies between design decisions, so that the order decisions are made matters to the final system implementation. Furthermore, there is a trade-off between heuristics for specific DSE, which improves the optimization results, and global optimizers, which improve the flexibility to be applied in different DSE scenarios. In order to overcome the identified challenges an MDE methodology for DSE is proposed. For this methodology a DSE Domain metamodel is proposed to represent relevant DSE concepts such as design space, design alternatives, evaluation method, constraints and others. Moreover, this metamodel represents different DSE problems, improving the flexibility of the proposed framework. Model transformations are used to implement DSE rules, which are used to constrain, guide, and generate design candidates. Focusing on the mapping between layers in a PBD approach, a novel design space abstraction is provided to represent multiple design decisions involved in the mapping as a single DSE problem. This abstraction is based on Categorical Graph Product, decoupling the exploration algorithm from the design space and being well suited to be implemented in automatic exploration tools. Upon this abstraction, the DSE method can benefit from the MDE methodology, opening new optimization opportunities, and improving the DSE integration into the development process and specification of DSE scenarios.
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Model driven engineering methodology for design space exploration of embedded systems / Metodologia de engenharia dirigida por modelos para exploração do espaço de projeto de sistemas embarcados / Modellgetriebene entwicklungsmethodik für die entwurfsraumexploration von eingebetteten systemeOliveira, Marcio Ferreira da Silva January 2013 (has links)
Heutzutage sind wir von Geräten umgeben, die sowohl Hardware wie auch Software- Komponenten beinhalten. Diese Geräte unterstützen ein breites Spektrum an verschiedenen Domänen, so zum Beispiel Telekommunikation, Luftfahrt, Automobil und andere. Derartige Systeme sind überall aufzufinden und werden als Eingebettete Systeme bezeichnet, da sie zur Informationsverarbeitung in andere Produkte eingebettet werden, wobei die Informationsverarbeitung des eingebetteten Systems jedoch nicht die bezeichnende Funktion des Produkts ist. Die ständig zunehmende Komplexität moderner eingebettete Systeme erfordert die Verwendung von mehreren Komponenten um die Funktionen von einem einzelnen System zu implementieren. Eine solche Steigerung der Funktionalität führt jedoch ebenfalls zu einem Wachstum in der Entwurfs-Komplexität, die korrekt und effizient beherrscht werden muss. Neben hohen Anforderungen bezüglich Leistungsaufnahme, Performanz und Kosten hat auch Time-to-Market-Anforderungen großen Einfluss auf den Entwurf von Eingebetteten Systemen. Design Space Exploration (DSE) beschreibt die systematische Erzeugung und Auswertung von Entwurfs-Alternativen, um die Systemleistung zu optimieren und den gestellten Anforderungen an das System zu genügen. Bei der Entwicklung von Eingebetteten Systemen, speziell beim Platform-Based Design (PBD) führt die zunehmende Anzahl von Design-Entscheidungen auf mehreren Abstraktionsebenen zu einer Explosion der möglichen Kombinationen von Alternativen, was auch für aktuelle DSE Methoden eine Herausforderung darstellt. Jedoch vermag üblicherweise nur eine begrenzte Anzahl von Entwurfs-Alternativen die zusätzlich formulierten nicht-funktionalen Anforderungen zu erfüllen. Darüber hinaus beeinflusst jede Entwurfs- Entscheidung weitere Entscheidungen und damit die resultierenden Systemeigenschaften. Somit existieren Abhängigkeiten zwischen Entwurfs-Entscheidungen und deren Reihenfolge auf dem Weg zur Implementierung des Systems. Zudem gilt es zwischen einer spezifischen Heuristik für eine bestimmte DSE, welche zu verbesserten Optimierungsresultaten führt, sowie globalen Verfahren, welche ihrerseits zur Flexibilität hinsichtlich der Anwendbarkeit bei verschiedenen DSE Szenarien beitragen, abzuwägen. Um die genannten Herausforderungen zu lösen wird eine Modellgetriebene Entwicklung (englisch Model-Driven Engineering, kurz MDE) Methodik für DSE vorgeschlagen. Für diese Methodik wird ein DSE-Domain-Metamodell eingeführt um relevante DSEKonzepte wie Entwurfsraum, Entwurfs-Alternativen, Auswertungs- und Bewertungsverfahren, Einschränkungen und andere abzubilden. Darüber hinaus modelliert das Metamodell verschiedenen DSE-Frage- stellungen, was zur Verbesserung der Flexibilität der vorgeschlagenen Methodik beiträgt. Zur Umsetzung von DSE-Regeln, welche zur Steuerung, Einschränkung und Generierung der Ent- wurfs-Alternativen genutzt werden, finden Modell-zu-Modell-Transformationen Anwendung. Durch die Fokussierung auf die Zuordnung zwischen den Schichten in einem PBDAnsatz wird eine neuartige Entwurfsraumabstraktion eingeführt, um multiple Entwurfsentscheidungen als singuläres DSE Problem zu repräsentieren. Diese auf dem Categorial Graph Product aufbauende Abstraktion entkoppelt den Explorations-Algorithmus vom Entwurfsraum und ist für Umsetzung in automatisierte Werkzeugketten gut geeignet. Basierend auf dieser Abstraktion profitiert die DSE-Methode durch die eingeführte MDEMethodik als solche und ermöglicht nunmehr neue Optimierungsmöglichkeiten sowie die Verbesserung der Integration von DSE in Entwicklungsprozesse und die Spezifikation von DSE-Szenarien. / Atualmente dispositivos contendo hardware e software são encontrados em todos os lugares. Estes dispositivos prestam suporte a uma varieadade de domínios, como telecomunicações, automotivo e outros. Eles são chamados “sistemas embarcados”, pois são sistemas de processamento montados dentro de produtos, cujo sistema de processamento não faz parte da funcionalidade principal do produto. O acréscimo de funções nestes sistemas implica no aumento da complexidade de seu projeto, o qual deve ser adequadamente gerenciado, pois além de requisitos rigorosos em relação à dissipação de potência, desempenho e custos, a pressão sobre o prazo para introdução de um produto no mercado também dificulta seu projeto. Exploração do espaço de projeto (DSE) é a atividade sistemática de gerar e avaliar alternativas de projetos, com o objetivo de otimizar suas propriedades. No desenvolvimento de sistemas embarcados, especialmente em Projeto Baseado em Plataformas (PBD), metodologias de DSE atuais são desafiadas pelo crescimento do número de decisões de projeto, o qual implica na explosão da combinação de alternativas. Porém, somente algumas destas resultam em projetos que atedem os requisitos nãofuncionais. Além disso, as decisões influenciam umas às outras, de forma que a ordem em que estas são tomadas alteram a implementação final do sistema. Outro desafio é o balanço entre flexibilidade da metodologia e seu desempenho, pois métodos globais de otimização são flexíveis, mas apresentam baixo desempenho. Já heurísticas especialmente desenvolvidas para o cenário de DSE em questão apresentam melhor desempenho, porém dificilmente são aplicáveis a diferentes cenários. Com o intuito de superar os desafios é proposta uma metodologia de projeto dirigido por modelos (MDE) adquada para DSE. Um metamodelo do domínio de DSE é definido para representar conceitos como espaço de projeto, métodos de avaliação e restrições. O metamodelo também representa diferentes problemas de DSE aprimorando a flexibilidade da metodologia. Regras de transformações de modelos implementam as regras de DSE, as quais são utilizadas para restringir e guiar a geração de projetos alternativos. Restringindo-se ao mapeamento entre camadas no PBD é proposta uma abstração para representar o espaço de projeto. Ela representa múltiplas decisões de projeto envolvidas no mapeamento como um único problema de DSE. Esta representação é adequada para a implementação em ferramentas automática de DSE e pode beneficiar o processo de DSE com uma abordagem de MDE, aprimorando a especificação de cenários de DSE e sua integração no processo de desenvolvimento. / Nowadays we are surrounded by devices containing hardware and software components. These devices support a wide spectrum of different domains, such as telecommunication, avionics, automobile, and others. They are found anywhere, and so they are called Embedded Systems, as they are information processing systems embedded into enclosing products, where the processing system is not the main functionality of the product. The ever growing complexity in modern embedded systems requires the utilization of more components to implement the functions of a single system. Such an increasing functionality leads to a growth in the design complexity, which must be managed properly, because besides stringent requirements regarding power, performance and cost, also time-to-market hinders the design of embedded systems. Design Space Exploration (DSE) is the systematic generation and evaluation of design alternatives, in order to optimize system properties and fulfill requirements. In embedded system development, specifically in Platform-Based Design (PBD), current DSE methodologies are challenged by the increasing number of design decisions at multiple abstraction levels, which leads to an explosion of combination of alternatives. However, only a reduced number of these alternatives leads to feasible designs, which fulfill non-functional requirements. Moreover, each design decision influences subsequent decisions and system properties, hence there are inter-dependencies between design decisions, so that the order decisions are made matters to the final system implementation. Furthermore, there is a trade-off between heuristics for specific DSE, which improves the optimization results, and global optimizers, which improve the flexibility to be applied in different DSE scenarios. In order to overcome the identified challenges an MDE methodology for DSE is proposed. For this methodology a DSE Domain metamodel is proposed to represent relevant DSE concepts such as design space, design alternatives, evaluation method, constraints and others. Moreover, this metamodel represents different DSE problems, improving the flexibility of the proposed framework. Model transformations are used to implement DSE rules, which are used to constrain, guide, and generate design candidates. Focusing on the mapping between layers in a PBD approach, a novel design space abstraction is provided to represent multiple design decisions involved in the mapping as a single DSE problem. This abstraction is based on Categorical Graph Product, decoupling the exploration algorithm from the design space and being well suited to be implemented in automatic exploration tools. Upon this abstraction, the DSE method can benefit from the MDE methodology, opening new optimization opportunities, and improving the DSE integration into the development process and specification of DSE scenarios.
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Model driven engineering methodology for design space exploration of embedded systems / Metodologia de engenharia dirigida por modelos para exploração do espaço de projeto de sistemas embarcados / Modellgetriebene entwicklungsmethodik für die entwurfsraumexploration von eingebetteten systemeOliveira, Marcio Ferreira da Silva January 2013 (has links)
Heutzutage sind wir von Geräten umgeben, die sowohl Hardware wie auch Software- Komponenten beinhalten. Diese Geräte unterstützen ein breites Spektrum an verschiedenen Domänen, so zum Beispiel Telekommunikation, Luftfahrt, Automobil und andere. Derartige Systeme sind überall aufzufinden und werden als Eingebettete Systeme bezeichnet, da sie zur Informationsverarbeitung in andere Produkte eingebettet werden, wobei die Informationsverarbeitung des eingebetteten Systems jedoch nicht die bezeichnende Funktion des Produkts ist. Die ständig zunehmende Komplexität moderner eingebettete Systeme erfordert die Verwendung von mehreren Komponenten um die Funktionen von einem einzelnen System zu implementieren. Eine solche Steigerung der Funktionalität führt jedoch ebenfalls zu einem Wachstum in der Entwurfs-Komplexität, die korrekt und effizient beherrscht werden muss. Neben hohen Anforderungen bezüglich Leistungsaufnahme, Performanz und Kosten hat auch Time-to-Market-Anforderungen großen Einfluss auf den Entwurf von Eingebetteten Systemen. Design Space Exploration (DSE) beschreibt die systematische Erzeugung und Auswertung von Entwurfs-Alternativen, um die Systemleistung zu optimieren und den gestellten Anforderungen an das System zu genügen. Bei der Entwicklung von Eingebetteten Systemen, speziell beim Platform-Based Design (PBD) führt die zunehmende Anzahl von Design-Entscheidungen auf mehreren Abstraktionsebenen zu einer Explosion der möglichen Kombinationen von Alternativen, was auch für aktuelle DSE Methoden eine Herausforderung darstellt. Jedoch vermag üblicherweise nur eine begrenzte Anzahl von Entwurfs-Alternativen die zusätzlich formulierten nicht-funktionalen Anforderungen zu erfüllen. Darüber hinaus beeinflusst jede Entwurfs- Entscheidung weitere Entscheidungen und damit die resultierenden Systemeigenschaften. Somit existieren Abhängigkeiten zwischen Entwurfs-Entscheidungen und deren Reihenfolge auf dem Weg zur Implementierung des Systems. Zudem gilt es zwischen einer spezifischen Heuristik für eine bestimmte DSE, welche zu verbesserten Optimierungsresultaten führt, sowie globalen Verfahren, welche ihrerseits zur Flexibilität hinsichtlich der Anwendbarkeit bei verschiedenen DSE Szenarien beitragen, abzuwägen. Um die genannten Herausforderungen zu lösen wird eine Modellgetriebene Entwicklung (englisch Model-Driven Engineering, kurz MDE) Methodik für DSE vorgeschlagen. Für diese Methodik wird ein DSE-Domain-Metamodell eingeführt um relevante DSEKonzepte wie Entwurfsraum, Entwurfs-Alternativen, Auswertungs- und Bewertungsverfahren, Einschränkungen und andere abzubilden. Darüber hinaus modelliert das Metamodell verschiedenen DSE-Frage- stellungen, was zur Verbesserung der Flexibilität der vorgeschlagenen Methodik beiträgt. Zur Umsetzung von DSE-Regeln, welche zur Steuerung, Einschränkung und Generierung der Ent- wurfs-Alternativen genutzt werden, finden Modell-zu-Modell-Transformationen Anwendung. Durch die Fokussierung auf die Zuordnung zwischen den Schichten in einem PBDAnsatz wird eine neuartige Entwurfsraumabstraktion eingeführt, um multiple Entwurfsentscheidungen als singuläres DSE Problem zu repräsentieren. Diese auf dem Categorial Graph Product aufbauende Abstraktion entkoppelt den Explorations-Algorithmus vom Entwurfsraum und ist für Umsetzung in automatisierte Werkzeugketten gut geeignet. Basierend auf dieser Abstraktion profitiert die DSE-Methode durch die eingeführte MDEMethodik als solche und ermöglicht nunmehr neue Optimierungsmöglichkeiten sowie die Verbesserung der Integration von DSE in Entwicklungsprozesse und die Spezifikation von DSE-Szenarien. / Atualmente dispositivos contendo hardware e software são encontrados em todos os lugares. Estes dispositivos prestam suporte a uma varieadade de domínios, como telecomunicações, automotivo e outros. Eles são chamados “sistemas embarcados”, pois são sistemas de processamento montados dentro de produtos, cujo sistema de processamento não faz parte da funcionalidade principal do produto. O acréscimo de funções nestes sistemas implica no aumento da complexidade de seu projeto, o qual deve ser adequadamente gerenciado, pois além de requisitos rigorosos em relação à dissipação de potência, desempenho e custos, a pressão sobre o prazo para introdução de um produto no mercado também dificulta seu projeto. Exploração do espaço de projeto (DSE) é a atividade sistemática de gerar e avaliar alternativas de projetos, com o objetivo de otimizar suas propriedades. No desenvolvimento de sistemas embarcados, especialmente em Projeto Baseado em Plataformas (PBD), metodologias de DSE atuais são desafiadas pelo crescimento do número de decisões de projeto, o qual implica na explosão da combinação de alternativas. Porém, somente algumas destas resultam em projetos que atedem os requisitos nãofuncionais. Além disso, as decisões influenciam umas às outras, de forma que a ordem em que estas são tomadas alteram a implementação final do sistema. Outro desafio é o balanço entre flexibilidade da metodologia e seu desempenho, pois métodos globais de otimização são flexíveis, mas apresentam baixo desempenho. Já heurísticas especialmente desenvolvidas para o cenário de DSE em questão apresentam melhor desempenho, porém dificilmente são aplicáveis a diferentes cenários. Com o intuito de superar os desafios é proposta uma metodologia de projeto dirigido por modelos (MDE) adquada para DSE. Um metamodelo do domínio de DSE é definido para representar conceitos como espaço de projeto, métodos de avaliação e restrições. O metamodelo também representa diferentes problemas de DSE aprimorando a flexibilidade da metodologia. Regras de transformações de modelos implementam as regras de DSE, as quais são utilizadas para restringir e guiar a geração de projetos alternativos. Restringindo-se ao mapeamento entre camadas no PBD é proposta uma abstração para representar o espaço de projeto. Ela representa múltiplas decisões de projeto envolvidas no mapeamento como um único problema de DSE. Esta representação é adequada para a implementação em ferramentas automática de DSE e pode beneficiar o processo de DSE com uma abordagem de MDE, aprimorando a especificação de cenários de DSE e sua integração no processo de desenvolvimento. / Nowadays we are surrounded by devices containing hardware and software components. These devices support a wide spectrum of different domains, such as telecommunication, avionics, automobile, and others. They are found anywhere, and so they are called Embedded Systems, as they are information processing systems embedded into enclosing products, where the processing system is not the main functionality of the product. The ever growing complexity in modern embedded systems requires the utilization of more components to implement the functions of a single system. Such an increasing functionality leads to a growth in the design complexity, which must be managed properly, because besides stringent requirements regarding power, performance and cost, also time-to-market hinders the design of embedded systems. Design Space Exploration (DSE) is the systematic generation and evaluation of design alternatives, in order to optimize system properties and fulfill requirements. In embedded system development, specifically in Platform-Based Design (PBD), current DSE methodologies are challenged by the increasing number of design decisions at multiple abstraction levels, which leads to an explosion of combination of alternatives. However, only a reduced number of these alternatives leads to feasible designs, which fulfill non-functional requirements. Moreover, each design decision influences subsequent decisions and system properties, hence there are inter-dependencies between design decisions, so that the order decisions are made matters to the final system implementation. Furthermore, there is a trade-off between heuristics for specific DSE, which improves the optimization results, and global optimizers, which improve the flexibility to be applied in different DSE scenarios. In order to overcome the identified challenges an MDE methodology for DSE is proposed. For this methodology a DSE Domain metamodel is proposed to represent relevant DSE concepts such as design space, design alternatives, evaluation method, constraints and others. Moreover, this metamodel represents different DSE problems, improving the flexibility of the proposed framework. Model transformations are used to implement DSE rules, which are used to constrain, guide, and generate design candidates. Focusing on the mapping between layers in a PBD approach, a novel design space abstraction is provided to represent multiple design decisions involved in the mapping as a single DSE problem. This abstraction is based on Categorical Graph Product, decoupling the exploration algorithm from the design space and being well suited to be implemented in automatic exploration tools. Upon this abstraction, the DSE method can benefit from the MDE methodology, opening new optimization opportunities, and improving the DSE integration into the development process and specification of DSE scenarios.
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Exergy and environmental assessment of FPSO offshore platforms with CO2 capture and storage. / Avaliação exergética e ambiental de plataformas offshore FPSO com captura e armazenamento de CO2.Yamid Alberto Carranza Sánchez 10 February 2017 (has links)
Offshore oil platforms are used for the exploitation and production of hydrocarbons and consist of a processing plant and a utility plant. The oil and gas industry operations are energy-intensive and, in the case of offshore platforms, the need to decrease energy consumption and reduce CO2 emissions has increased. In the oil and gas industry, the ISO 50001 standard promotes the implementation of energy management systems and proposes indicators based on energy. Interestingly, after several decades of knowledge of the concept of exergy, this has not been formally implemented in the programs and strategies of the oil and gas industry organizations. In this research, the implementation of the exergy method and the carbon capture and storage strategy for the assessment of the performance of a floating, production and storage offloading units FPSO is proposed. FPSO platforms and their processing and utility plants may have different configurations depending on, among others, the reservoir characteristics and production requirements. The possible configurations can therefore be numerous. In this sense, some operation scenarios based on different well-fluid compositions and operation modes are studied. The platform models are developed and simulated using the software Aspen HYSYS®. Results show that, on average, the reduction of 88.8% in CO2 emissions is penalized with a reduction in exergy efficiency of 1.7 points. Further, results allow a better understanding of exergy and environmental performance of the FPSO. / Plataformas de petróleo offshore são utilizadas para a exploração e produção de hidrocarbonetos e consistem em uma planta de processamento e uma planta de utilidade. As operações da indústria de petróleo e gás são de energia intensiva e, no caso de plataformas offshore, é necessário cada vez mais diminuir o consumo de energia e reduzir as emissões de CO2. Na indústria de petróleo e gás, a norma ISO 50001 promove a implementação de sistemas de gestão de energia e propõe indicadores baseados em energia. Entretanto, após várias décadas de conhecimento do conceito de exergia, este não foi formalmente implementado nos programas e estratégias das organizações da indústria de petróleo e gás. Neste trabalho, propõe-se a implementação da análise exergética e a estratégia de captura e armazenamento de carbono para a avaliação do desempenho de unidades flutuantes, de produção, de armazenamento e transferência FPSO. As plataformas FPSO e suas plantas de processamento e utilidade podem ter diferentes configurações dependendo, entre outras, das características do reservatório e dos requisitos de produção. As configurações possíveis podem, portanto, ser numerosas. Neste sentido, são estudados alguns cenários de operação baseados em diferentes composições dos fluidos do poço e em três modos de operação. Os modelos de plataforma são desenvolvidos e simulados usando o software Aspen HYSYS®. Os resultados mostram que, em média, a redução de 88,8% nas emissões de CO2 é penalizada com uma redução da eficiência exergética de 1,7 pontos. Além disso, os resultados permitem uma melhor compreensão da exergia e desempenho ambiental do FPSO.
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