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Service quality and profit control in utility computing service life cyclesHeckmann, Benjamin January 2013 (has links)
Utility Computing is one of the most discussed business models in the context of Cloud Computing. Service providers are more and more pushed into the role of utilities by their customer's expectations. Subsequently, the demand for predictable service availability and pay-per-use pricing models increases. Furthermore, for providers, a new opportunity to optimise resource usage offers arises, resulting from new virtualisation techniques. In this context, the control of service quality and profit depends on a deep understanding of the representation of the relationship between business and technique. This research analyses the relationship between the business model of Utility Computing and Service-oriented Computing architectures hosted in Cloud environments. The relations are clarified in detail for the entire service life cycle and throughout all architectural layers. Based on the elaborated relations, an approach to a delivery framework is evolved, in order to enable the optimisation of the relation attributes, while the service implementation passes through business planning, development, and operations. Related work from academic literature does not cover the collected requirements on service offers in this context. This finding is revealed by a critical review of approaches in the fields of Cloud Computing, Grid Computing, and Application Clusters. The related work is analysed regarding appropriate provision architectures and quality assurance approaches. The main concepts of the delivery framework are evaluated based on a simulation model. To demonstrate the ability of the framework to model complex pay-per-use service cascades in Cloud environments, several experiments have been conducted. First outcomes proof that the contributions of this research undoubtedly enable the optimisation of service quality and profit in Cloud-based Service-oriented Computing architectures.
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Modelos de previsão da despassivação das armaduras em estruturas de concreto sujeitas à carbonatação. / Prediction models of the despassivation of reinforcement steel in concrete structures due to carbonation.Carmona, Thomas Garcia 10 June 2005 (has links)
Este trabalho é iniciado apresentando os conceitos teóricos necessários para o bom entendimento do tema tratado, incluindo corrosão de armaduras, passivação, despassivação, vida útil e também conceitos de análise de riscos e teoria da confiabilidade. No terceiro capítulo é feita a revisão bibliográfica das variáveis que influem na carbonatação do concreto, apresentando um panorama do conhecimento atual sobre o tema, tanto no Brasil como no exterior. No quarto capítulo são apresentados e discutidos os modelos de previsão da carbonatação sendo também feitas comparações entre os resultados obtidos pelos modelos principais. No capítulo cinco é apresentado o trabalho experimental que objetiva contribuir com o conhecimento sobre a variabilidade da carbonatação e dos cobrimentos por meio de um estudo de caso real. A estrutura estudada foi o subsolo de um edifício residencial na zona central da cidade de São Paulo, no qual foram feitas diversas medidas de profundidade de carbonatação, cobrimentos de armaduras, concentração de CO2 ambiente e umidade relativa do ar. Os resultados foram tratados por meio de análise de variância e os valores de profundidade de carbonatação foram comparados com os valores previstos empregando modelos de previsão. Foi realizado o cálculo teórico da probabilidade de despassivação que foi comparada com a incidência real de despassivação observada. Os coeficientes de variação encontrados também foram comparados com os resultados de outras pesquisas atuais. É apresentado o desenvolvimento de um programa computacional para previsão do período de iniciação por métodos deterministas e probabilistas. / This work starts presenting the theoretical concepts needed for a good understanding of its contents, including corrosion of steel in concrete, passivation, despassivation, service life and concepts of risk analysis and reliability theory. In chapter three its discussed the several variables that have influence in concrete carbonation, presenting a general view of the knowledge concerning the topic in Brasil and other countries. Chapter four presents and discuss the prediction models of carbonation and comparisons are made between the results of the main models. In chapter five it is presented the experimental work that intends to contribute with the knowledge about the carbonation and concrete covers variability by means of a case study. The studied structure was the parking garage of a 30 years residential building, located in the central zone of São Paulo city in Brasil, in witch were made a several number of measurements of carbonation depth, concrete cover, CO2 concentration and air relative humidity. The collected data was analyzed using variance analysis and the values of carbonation depth were compared with that estimated using prediction models. The theoretical calculation of the despassivation probability was compared with the real despassivation incidence. The variation coefficients obtained were almost compared with the results of other recent investigations. It is still presented the development of a computer program for predicting the initiation period using deterministic and probabilistic methods.
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O conceito de desempenho de edificações e a sua importância para o setor da construção civil no Brasil. / The concept of building performance and its importance for the construction sector in Brazil.Borges, Carlos Alberto de Moraes 22 July 2008 (has links)
O conceito de desempenho na construção civil está, há muitos anos, associado ao comportamento em uso nas edificações, dentro de determinadas condições. O desafio mundial é que este comportamento atenda às expectativas dos usuários das edificações ao longo de uma determinada vida útil e dentro da realidade técnica e socioeconômica de cada país e empreendimento. Apesar do conceito de desempenho estar consolidado no meio acadêmico, sua aplicação prática é bastante difícil e envolve muitos conflitos de interesses. No caso brasileiro, com o grande crescimento que o mercado da construção civil experimenta neste momento, e com a publicação da primeira Norma Brasileira de Desempenho de Edificações, prevista para 2008, é oportuno que haja uma reflexão sobre como atendê-la e utilizá-la, além do próprio conceito de desempenho em beneficio de todos os agentes do setor. A proposta desta dissertação de mestrado é fazer uma pesquisa abrangente sobre a evolução conceitual do tema desempenho na construção civil, demonstrar a importância estratégica da sua aplicação no Brasil para a evolução do setor, e propor caminhos para a efetiva utilização da norma brasileira de desempenho de edificações. / The performance concept in building has been, for many years, associated with the behaviour in use of buildings, within certain conditions. The global challenge is to make this behaviour meet the users expectations throughout a specific service life and within the technical and socioeconomic reality of each country or site. Although the performance concept is already consolidated in the academic world, its practical application is very difficult and involves many conflicts of interest. In the Brazilian scenario, with the large growth experienced by the building construction segment at this moment, and with the upcoming publication of the first Brazilian Performance Based Building Code in 2008, it is convenient to establish a reflection on how to meet and use this code and its own performance concept to the advantage of all players in the business. The proposal of this Masters Dissertation is to provide a broad research on the conceptual evolution of the performance-based theme in building; to demonstrate its strategic importance of this application in Brazil for the evolution of the sector; and to propose a path for the effective use of the Brazilian performance-based building code.
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O conceito de desempenho de edificações e a sua importância para o setor da construção civil no Brasil. / The concept of building performance and its importance for the construction sector in Brazil.Carlos Alberto de Moraes Borges 22 July 2008 (has links)
O conceito de desempenho na construção civil está, há muitos anos, associado ao comportamento em uso nas edificações, dentro de determinadas condições. O desafio mundial é que este comportamento atenda às expectativas dos usuários das edificações ao longo de uma determinada vida útil e dentro da realidade técnica e socioeconômica de cada país e empreendimento. Apesar do conceito de desempenho estar consolidado no meio acadêmico, sua aplicação prática é bastante difícil e envolve muitos conflitos de interesses. No caso brasileiro, com o grande crescimento que o mercado da construção civil experimenta neste momento, e com a publicação da primeira Norma Brasileira de Desempenho de Edificações, prevista para 2008, é oportuno que haja uma reflexão sobre como atendê-la e utilizá-la, além do próprio conceito de desempenho em beneficio de todos os agentes do setor. A proposta desta dissertação de mestrado é fazer uma pesquisa abrangente sobre a evolução conceitual do tema desempenho na construção civil, demonstrar a importância estratégica da sua aplicação no Brasil para a evolução do setor, e propor caminhos para a efetiva utilização da norma brasileira de desempenho de edificações. / The performance concept in building has been, for many years, associated with the behaviour in use of buildings, within certain conditions. The global challenge is to make this behaviour meet the users expectations throughout a specific service life and within the technical and socioeconomic reality of each country or site. Although the performance concept is already consolidated in the academic world, its practical application is very difficult and involves many conflicts of interest. In the Brazilian scenario, with the large growth experienced by the building construction segment at this moment, and with the upcoming publication of the first Brazilian Performance Based Building Code in 2008, it is convenient to establish a reflection on how to meet and use this code and its own performance concept to the advantage of all players in the business. The proposal of this Masters Dissertation is to provide a broad research on the conceptual evolution of the performance-based theme in building; to demonstrate its strategic importance of this application in Brazil for the evolution of the sector; and to propose a path for the effective use of the Brazilian performance-based building code.
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Best Before : A selective service life analysis of denim fabrics with a focus on washing and drying degradation to optimize their recycling efficiencySchlich, Marie, Neuss, Joanna January 2019 (has links)
Resource scarcity and increasing environmental pressure have raised the stakes for rethinking material efficiency and textile recycling potential. As current practices fail to feed a closed loop recycling system, this research aims to contribute to the improvement of prevailing practices regarding denim as one of the most popular apparel materials worldwide while focusing on the issue of increasing amounts of discarded post-consumer textiles. The superordinate objective to define the optimum point for denim recycling to retain the value of the cotton fibre as long as possible in a closed loop system, thereby elevating the recycling efficiency, can be considered a key driver for the present research. The following data acquisition is constructed and executed along a mixed method research, in which a qualitative approach based on expert interviews informs and builds up on the quantitative counter part of laboratory use simulation testing on two different denim fabrics and vice versa, leading to an embedded research design. A subjective assessment of potential alterations of the denim fabrics’ visual and tactile characteristics, caused by the use simulation, provides quantitative data through an employed expert panel, which is enhanced by objectively recorded results from the conducted tear strength test and comparative weight investigation to inform changes regarding the physical properties. The applied research methods provide parameters to monitor the decomposition and weakening of the overall fabric structure throughout the experiment. The analysis of the data allowed to assign the number of washing and drying cycles, that a denim garment has undergone, to a corresponding degree of degradation. The presented findings are a valuable resource for developing and innovating current open-end recycling options. The maintenance of the raw material value throughout various reprocessing cycles can counteract the elevated natural fibre scarcity. The insights on the material and process level build a fundament for the successful operationalisation and management of sustainable recycling practices. Further research in this field can pave the way towards value retaining circularity.
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Comportement d'un composite à matrice céramique en fatigue et mise en place d'indicateurs d'endommagement par émission acoustique / Behaviour of a ceramic matrix composite under fatigue loading and definition of damge indicators based on acoustic emissionRacle, Elie 11 September 2015 (has links)
La compréhension du comportement d'un composite à matrice céramique (CMC) lorsqu'il est sollicité en fatigue est l'un des points clés pour permettre son utilisation dans un cadre industriel. Il est en effet nécessaire de déterminer la chronologie des différents mécanismes d'endommagement ainsi que d'estimer la durée de vie en conditions d'utilisation. Il est alors nécessaire de réaliser une caractérisation mécanique mais aussi de définir des indicateurs d'endommagement permettant la prévision de durée de vie. Dans ce but, il est intéressant de coupler l'analyse des paramètres mécaniques et les observations microstructurales à des techniques de suivi en temps réel de l'endommagement. L'émission acoustique (EA) est une méthode de suivi non destructive qui permet de répondre à cette problématique. Elle permet notamment de quantifier et de localiser l'endommagement. Dans ce travail, de nouveaux indicateurs d'endommagement sont mis en place tels la "Sévérité" des signaux définie à partir de l'énergie acoustique ainsi que la "Sentry function" définie à partir de l'énergie acoustique et de l'énergie mécanique. Ce travail s'articule autour de deux principaux axes. Dans un premier temps il s'agit de caractériser les effets de la sollicitation cyclique sur ce type de matériau, ceci notamment en comparant l'évolution des paramètres mécaniques, les observations microstructurales ainsi que l’analyse de l'évolution globale de l'émission acoustique (EA) lorsque le matériau est soumis à un chargement statique et à un chargement cyclique. La seconde partie consiste à déterminer un scenario d'endommagement. Dans un premier temps, les signaux d’EA sont analysés en fonction de leur détection dans le cycle (charge/décharge). Ensuite la détermination de la signature acoustique des différents mécanismes d'endommagement par application de techniques de reconnaissance de formes supervisées a permis d'évaluer leur chronologie d'activation durant les essais de fatigue cyclique. Cette étude a permis de mettre en évidence un ensemble de mécanismes propres à la sollicitation cyclique, composé principalement de décohésion et de frottement aux interfaces fibre/matrice et matrice/matrice. De plus, l'utilisation de l'émission acoustique a permis de définir des temps caractéristiques ou critiques pouvant être utilisés dans un objectif de prévision de la durée de vie. En effet, par exemple la sévérité des signaux a permis de mettre en évidence un temps caractéristique situé entre 25 et 45% de la durée de vie du matériau. La détection en temps réel de ce temps caractéristique permet d'estimer la durée de vie restante. / The full understanding of a ceramic matrix composite under fatigue loading is needed in view of industrial applications. It is necessary to determine the damage mechanisms chronology and to be able to forecast the lifetime of the material in the conditions of use. To reach these purposes, a mechanical characterisation has to be done as well as the definition of damage indicators. It is then interesting to link the analysis of mechanical parameters and microscope observations with a non-destructive monitoring technique. Acoustic emission (AE) appears to be a good candidate to monitor material damage under loading. It makes the quantification and the material damage localisation possible. In this study, indicators based on released acoustic energy are used as "Severity" of signals or "Sentry function" which depends on both acoustic and mechanical energies. This work is organised in two parts. First, the analysis of mechanical parameters behaviour, material microstructure and global evolution of acoustic emission under static and cyclic loading makes the characterisation of the effects of cyclic fatigue on the material possible. The second part consists in determining a damage scenario. First acoustic emission signals are analysed depending on their acquisition during a cycle (loading or unloading). Then the connection between the acoustic emission signals and the different damage mechanisms, using a supervised clustering method, facilitated the estimation of the activation of these different damage mechanisms during cyclic fatigue tests. This study pointed out different damage mechanisms generated by cyclic loading, which are mainly debonding and friction at matrix/fibre and matrix/matrix interfaces. In addition, damage indicators based on acoustic emission enabled to determine characteristic times which can be used for lifetime forecast. For example, signal severity shows a characteristic time between 25% and 45% of the time to ultimate failure. Detection of this time in real-time during a test can be used to estimate the time of the ultimate failure of the material.
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Web 2.0 服務發展生命週期管理之研究 / The management of Web 2.0 services development life cycle林俊成, Lin, Chun-Cheng Unknown Date (has links)
本研究動機是希望透過Web 2.0服務以善用集體智慧,目的在建立一個Web2.0服務發展的管理架構。從文獻中,我們整理Web2.0服務發展的特性,發現共創者和訪客的取得是經營Web2.0服務最重要的任務。根據印象管理理論以及臉書和維基百科兩個Web2.0服務發展過程,這項研究提出了一個四階段的Web 2.0服務發展生命週期。這四個階段依序是:模式確立、創新傳播、社群擴展和服務再造。除此之外,針對每一個階段,這項研究提出四個管理面向。這四個管理面向是:共創者管理、內容管理、控制管理和動態能力管理。接著我們深入探討台灣六個Web2.0服務的案例—玩運彩、愛評網、地圖日記、愛合購、MyGo和WEnews,進一步驗證我們提出的管理架構,並且豐富我們對Web2.0服務發展生命周期的認識。透過對於Web2.0服務發展生命週期的深入探討,期許研究成果能提供給Web 2.0服務管理者做為在管理上的參考依據。 / This study is motivated by the prospect of harvesting the collective intelligence of the Internet via Web 2.0 services and aims at building a framework for the management of Web 2.0 services development. By reviewing specific features of Web 2.0 services, we identify the acquisition of co-creators and viewers as the most influential task of Web 2.0 service development. Based on impression management theory and two typical Web 2.0 cases—Facebook and Wikipedia—we distinguish four phases of co-creator and viewer development throughout the life cycle of Web 2.0 services. The four phases are: model establishment, innovation dispersion, community expansion, and service re-invention. Besides, we also identify four dimensions of the management of Web 2.0 services development. The four dimensions are: co-creator, content, control, and dynamic capability. The four phases and the four management dimensions of Web 2.0 service development life cycle are then validated by industry experts and enriched by six Taiwan Web 2.0 service cases—PlaySport, iPeen, AnswerBox, ihergo, MyGo and WEnews. It is hoped that the elaboration of the life cycle of Web 2.0 services development can provide strategic input into the management of Web 2.0 services.
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Carrier Grade Adaptation for an IP-based Multimodal Application Server: Moving the SoftBridge into SLEESun, Tao January 2004 (has links)
<p>Providing carrier grade characteristics for Internet Protocol (IP) communication applications is a significant problem for IP application providers in order to offer integrated services that span IP  / and telecommunication networks. This thesis addresses the provision of life-cycle management, which is only one carrier grade characteristic, for a SoftBridge application, which is an example of IP communication applications. A SoftBridge provides semi-synchronous multi-modal IP-based communication. The work related to IP-Telecommunication integrated services and the SoftBridge is analyzed with respect to life-cycle management in a literature review. It is suggested to use an Application Server in a Next Generation Network (NGN) to provide life-cyclemanagement functionality for IP-Telecommunication applications. In this thesis, the Application Server is represented by a JAIN Service Logic Execution Environment(JSLEE), in which  / a SoftBridge application can be deployed, activated, deactivated, uninstalled and upgraded online.Two methodologies are applied in this research: exploratory prototyping, which evolves the development of a SoftBridge application, and empirical comparison, which is concerned with the empirical evaluation of a SoftBridge application in terms of carriergrade capabilities. A SoftBridge application called SIMBA  / provides a Deaf Telephony service similar to aprevious Deaf Telephony SoftBridge, However, SIMBA&rsquo / s SoftBridge design and implementation are unique to this thesis. In order to test the life-cycle  / management ability of SIMBA, an empirical evaluation is carried out including the experiments oflife-cycle management and call-processing performance. The final experimental results of the evaluation show that a JSLEE is able to provide life-cycle management for SIMBA without causing a significant decrease in performance. In conclusion, the life-cycle management can be provided  / or a SoftBridge application by using an Application Server such as a JSLEE. Futhermore, the results indicate that  / approach of using Application Server (JSLEE) integration should be  / sufficiently general to provide life cycle management, and indeed other carrier grade capabilities, for other IP communication applications. This allows IP communication applications to be  /   /   / integrated into an NGN.</p>
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Thermo-mechanical fatigue crack growth modeling of a nickel-based superalloyBarker, Vincent Mark 10 May 2011 (has links)
A model was created to predict the thermo-mechanical fatigue crack growth rates under typical engine spectrum loading conditions. This model serves as both a crack growth analysis tool to determine residual lifetime of ageing turbine components and as a design tool to assess the effects of temperature and loading variables on crack propagation. The material used in the development of this model was a polycrystalline superalloy, Inconel 100 (IN-100).
The first step in creating a reliable model was to define the first order effects that influence TMF crack growth in a typical engine spectrum. Load interaction effects were determined to be major contributors to lifetime estimates by influencing crack growth rates based upon previous load histories. A yield zone model was modified to include temperature dependent properties that controlled the effects of crack growth retardation and acceleration based upon overloads and underloads, respectively. Multiple overload effects were included in the model to create enhanced retardation compared to single overload tests. Temperature interaction effects were also considered very important due to the wide temperature ranges of turbine engine components. Oxidation and changing temperature effects were accounted for by accelerating crack growth in regions that had been affected by higher temperatures. Constant amplitude crack growth rates were used as a baseline, upon which load and temperature interaction effects were applied. Experimental data of isolated first order effects was used to calibrate and verify the model.
Experimental data provided the means to verify that the model was a good fit to experimental results. The load interaction effects were described by a yield zone model, which included temperature dependent properties. These properties were determined experimentally and were essential in the model's development to include load and temperature contributions. Other interesting factors became apparent through testing. It was seen that specific combinations of strain rate and temperature would lead to serrated yielding, discovered to be the Portevin-Le Chatelier effect. This effect manifested itself as enhanced hardening, leading to unstable strain bursts in specimens that cyclically yielded while changing temperature.
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Electrochemical assessment and service-life prediction of mechanically stabilized earth walls backfilled with crushed concrete and recycled asphalt pavementEsfeller, Michael Watts, Jr. 02 June 2009 (has links)
A Mechanically Stabilized Earth (MSE) wall is a vertical grade separation that
uses earth reinforcement extending laterally from the wall to take advantage of earth
pressure to reduce the required design strength of the wall. MSE wall systems are often
prefabricated to reduce construction time, thus improving constructability when
compared with conventionally cast-in-place reinforced wall systems. However, there is a
lack of knowledge for predicting the service-life of MSE retaining wall systems when
recycled backfill materials such as Recycled Asphalt Pavement (RAP) and Crushed
Concrete (CC) are used instead of Conventional Fill Material (CFM). The specific
knowledge missing is how these recycled materials, when used as backfill in MSE wall
systems, affects the corrosion rate of the reinforcing strips. This work addresses this
knowledge gap by providing recommendations for MSE wall systems backfilled with CC
or RAP, and provides a guide to predict the service-life based on corrosion rate test data
obtained from embedding steel and galvanized-steel earth reinforcing strips embedded in
MSE wall systems backfilled with CC, RAP, and CFM. Experimental data from samples
emulating MSE wall systems with steel and galvanized-steel reinforcing strips embedded
in CC and RAP were compared to samples with strips embedded in CFM. The results of
the testing provide data and methodologies that may, depending on the environmental
exposure conditions, justify the use of RAP and CC for the construction of MSE walls. If
these backfill materials are obtained from the construction site, this could provide a
significant cost savings during construction.
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