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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The Making of a Conceptual Design for a Balancing Tool

Eriksson, Jonas January 2014 (has links)
Balancing is usually done in the later phases of creating a game to make sure everything comes together to an enjoyable experience. Most of the time balancing is done with a series of playthroughs by the designers or by outsourced play testers and the imbalances found are corrected followed by more playthroughs. This method occupies a lot of time and might therefore not find everything. In this study I use information gathered from interviews with experienced designers and designer texts along with features from methods frequently used for aiding the designers to make a conceptual design of a tool that is aimed towards simplifying the process of balancing and reducing the amount of work hours having to be spent on this phase.
22

Knowledge Based Integrated Multidisciplinary Aircraft Conceptual Design

Munjulury, Venkata Raghu Chaitanya January 2014 (has links)
With the ever growing complexity of aircrafts, new tools and eventually methods to use these tools are needed in aircraft conceptual design. To reduce the development cost, an enhancement in the conceptual design is needed. This thesis presents a knowledge-based aircraft geometry design tool RAPID and the methodology applied in realizing the design. The parameters used to create a geometry need to be exchange between different tools. This is achieved by using a centralized database or onedata concept. One-database will enable creating a less number of cross connections between different tools to exchange data with one another. Different types of aircraft configurations can be obtained with less effort. As RAPID is developed based on relational design, any changes made to the geometric model will update automatically. The geometry model is carefully defined to carry over to the preliminary design. The validation of RAPID is done by implementing it in different aircraft design courses at Linköping University. In the aircraft project course, RAPID was effectively used and new features were added to the obtained desired design. Knowledge-base is used to realize the design performance for the geometry with an integrated database approach for a multidisciplinary aircraft conceptual design.
23

A reliability-based measurement of interoperability for conceptual-level systems of systems

Jones Wyatt, Elizabeth Ann 27 August 2014 (has links)
The increasing complexity of net-centric warfare requires assets to cooperate to achieve mission success. Such cooperation requires the integration of many heterogeneous systems into an interoperable system-of-systems (SoS). Interoperability can be considered a metric of an architecture, and must be understood as early as the conceptual design phase. This thesis approaches interoperability by first creating a general definition of interoperability, identifying factors that affect it, surveying existing models of interoperability, and identifying fields that can be leveraged to perform a measurement, including reliability theory and graph theory. The main contribution of this thesis is the development of the Architectural Resource Transfer and Exchange Measurement of Interoperability for Systems of Systems, or ARTEMIS methodology. ARTEMIS first outlines a quantitative measurement of system pair interoperability using reliability in series and in parallel. This step incorporates operational requirements and the capabilities of the system pair. Next, a matrix of interoperability values for each resource exchange in an operational process is constructed. These matrices can be used to calculate the interoperability of a single resource exchange, IResource, and layered to generate a weighted adjacency matrix of the entire SoS. This matrix can be plugged in to a separate model to link interoperability with the mission performance of the system of systems. One output of the M&S is a single value ISoS that can be used to rank architecture alternatives based on their interoperability. This allows decision makers to narrow down a large design space quickly using interoperability as one of several criteria, such as cost, complexity, or risk. A canonical problem was used to test the methodology. A discrete event simulation was constructed to model a small unmanned aircraft system performing a search and rescue mission. Experiments were performed to understand how changing the systems' interoperability affected the overall interoperability; how the resource transfer matrices were layered; and if the outputs could be calculated without time- and computationally-intensive stochastic modeling. It was found that although a series model of reliability could predict a range of IResource, M&S is required to provide exact values useful for ranking. Overall interoperability ISoS can be predicted using a weighted average of IResource, but the weights must be determined by M&S. Because a single interoperability value based on performance is not unique to an architecture configuration, network analysis was conducted to assess further properties of a system of systems that may affect cost or vulnerability of the network. The eigenvalue-based Coefficient of Networked Effects (CNE) was assessed and found to be an appropriate measure of network complexity. Using the outputs of the discrete event simulation, it was found that networks with higher interoperability tended to have more networked effects. However, there was not enough correlation between the two metrics to use them interchangeably. ARTEMIS recommends that both metrics be used to assess a networked SoS. This methodology is of extreme value to decision-makers by enabling trade studies at the SoS level that were not possible previously. It can provide decision-makers with information about an architecture and allow them to compare existing and potential systems of systems during the early phases of acquisition. This method is unique because it does not rely on qualitative assessments of technology maturity or adherence to standards. By enabling a rigorous, objective mathematical measurement of interoperability, decision-makers will better be able to select architecture alternatives that meet interoperability goals and fulfill future capability requirements.
24

Dark Ages Lunar Interferometer : Deployment Rover - Suspension System and Transition Mecanism

Pasalic, Haris, Bernfort, Björn January 2014 (has links)
This thesis is a continuation of last year's work and it builds on earlier construction of a rover that will deploy an interferometer on the far side of the moon. The project is done in collaboration with (JPL) Jet Propulsion Laboratoryin Pasadena, California. Given the size of the mission, accuracy and time limit project has been split into several smaller projects. The areas that are the focus of this project are the suspension and the transition system. The transition system that is originated from the stage when the rover transforms from the transit mode to ready mode, and the suspension system, are in this thesis work presented by detailed conceptual design. The next step, not mentioned this thesis work, will be to perform aprimary structure design on the details. The project owner’s ultimate goal is to create a better understanding about the origins of the universe and its continual changing. This would give scientists an opportunity to study some of the most fundamental questions that are still are waiting for answers. Together with a group of energy engineers, Gustav Andersson and Emil Ericsson, we were caught by the very attractive project assignment, well aware that not many people get the chance or the opportunity to be involved or work with projects like this.
25

CONTRAST: A conceptual reliability growth approach for comparison of launch vehicle architectures

Zwack, Mathew R. 12 January 2015 (has links)
In 2004, the NASA Astronaut Office produced a memo regarding the safety of next generation launch vehicles. The memo requested that these vehicles have a probability of loss of crew of at most 1 in 1000 flights, which represents nearly an order of magnitude decrease from current vehicles. The goal of LOC of 1 in 1000 flights has since been adopted by the launch vehicle design community as a requirement for the safety of future vehicles. This research addresses the gap between current vehicles and future goals by improving the capture of vehicle architecture effects on reliability and safety. Vehicle architecture pertains to the physical description of the vehicle itself, which includes manned or unmanned, number of stages, number of engines per stage, engine cycle types, redundancy, etc. During the operations phase of the vehicle life-cycle it is clear that each of these parameters will have an inherent effect on the reliability and safety of the vehicle. However, the vehicle architecture is typically determined during the early conceptual design phase when a baseline vehicle is selected. Unless a great amount of money and effort is spent, the architecture will remain relatively constant from conceptual design through operations. Due to the fact that the vehicle architecture is essentially “locked-in” during early design, it is expected that much of the vehicle's reliability potential will also be locked-in. This observation leads to the conclusion that improvement of vehicle reliability and safety in the area of vehicle architecture must be completed during early design. Evaluation of the effects of different architecture decisions must be performed prior to baseline selection, which helps to identify a vehicle that is most likely to meet the reliability and safety requirements when it reaches operations. Although methods exist for evaluating reliability and safety during early design, weaknesses exist when trying to evaluate all architecture effects simultaneously. The goal of this research was therefore to formulate and implement a method that is capable of quantitatively evaluating vehicle architecture effects on reliability and safety during early conceptual design. The ConcepTual Reliability Growth Approach for CompariSon of Launch Vehicle ArchiTectures (CONTRAST) was developed to meet this goal. Using the strengths of existing techniques a hybrid approach was developed, which utilizes a reliability growth projection to evaluate the vehicles. The growth models are first applied at the subsystem level and then a vehicle level projection is generated using a simple system level fault tree. This approach allows for the capture of all trades of interest at the subsystem level as well as many possible trades at the assembly level. The CONTRAST method is first tested on an example problem, which compares the method output to actual data from the Space Transportation System (STS). This example problem illustrates the ability of the CONTRAST method to capture reliability growth trends seen during vehicle operations. It also serves as a validation for the development of the reliability growth model assumptions for future applications of the method. The final chapter of the thesis applies the CONTRAST method to a relevant launch vehicle, the Space Launch System (SLS), which is currently under development. Within the application problem, the output of the method is first used to check that the primary research objective has been met. Next, the output is compared to a state-of-the-art tool in order to demonstrate the ability of the CONTRAST method to alleviate one of the primary consequences of using existing techniques. The final section within this chapter presents an analysis of the booster and upper stage block upgrade options for the SLS vehicle. A study of the upgrade options was carried out because the CONTRAST method is uniquely suited to look at the effects of such strategies. The results from the study of SLS block upgrades give interesting observations regarding the desired development order and upgrade strategy. Ultimately this application problem demonstrates the merits of applying the CONTRAST method during early design. This approach provides the designer with more information in regard to the expected reliability of the vehicle, which will ultimately enable the selection of a vehicle baseline that is most likely to meet the future requirements.
26

The Role of Mental Imagery in Conceptual Designing

Bilda, Zafer January 2006 (has links)
PhD / In design literature, how designers think and how they design have been identified as a reflection of how they interact with their sketches. Sketching in architectural design is still a central concern which shapes our understanding of the design process and the development of new tools. Sketching not only serves as a visual aid to store and retrieve conceptualisations, but as a medium to facilitate more ideas, and to revise and refine these ideas. This thesis examined how mental imagery and sketching is used in designing by conducting a protocol analysis study with six expert architects. Each architect was required to think aloud and design under two different conditions: one in which s/he had access to sketching and one in which s/he was blindfolded (s/he did not have access to sketching). At the end of the blindfold condition the architects were required to quickly sketch what they held in their minds. The architects were able to come up with satisfying design solutions and some reported that using their imagery could be another way of designing. The resulting sketches were assessed by judges and were found to have no significant differences in overall quality. Expert architects were able to construct and maintain the design of a building without having access to sketching. The analysis of the blindfold and sketching design protocols did not demonstrate any differences in the quantity of cognitive actions in perceptual, conceptual, functional and evaluative categories. Each architect’s cognitive structure and designing behaviour in the blindfold activity mimicked her/his cognitive structure and designing behaviour in the sketching activity. The analysis of links between the design ideas demonstrated that architects’ performance in idea development was higher under the blindfold condition, compared to their sketching condition. It was also found that architects’ blindfold design performance was improved when they were more familiar with the site layout. These results imply that expert designers may not need sketching as a medium for their reflective conversation with the situation. This study indicates that constructing internal representations can be a strong tool for designing. Future studies may show that designers may not need sketching for the generation of certain designs during the early phases of conceptual designing.
27

Métodos de modularização no projeto conceitual de desenvolvimento de produtos

Sonego, Monique January 2013 (has links)
A estratégia de modularização tem como objetivo desenvolver arquiteturas de produto que contenham unidades fisicamente destacáveis, denominados módulos, de forma a permitir que estas unidades sejam utilizadas em variações de um produto ou em linhas de produtos diferentes. Essa estratégia deve ser planejada no Processo de Desenvolvimento de Produto (PDP), no qual são tomadas decisões que afetam todo o ciclo de vida do produto. Com esse propósito, métodos e técnicas de modularização foram criados para oferecer suporte às equipes de desenvolvimento. Estes métodos precisam ser adaptados às características de cada projeto, como a natureza do negócio, a complexidade e a novidade do produto desenvolvido. Para contribuir com esse tema de pesquisa, o objetivo geral desta dissertação é propor uma reestruturação de métodos de modularização para a criação e avaliação de conceitos, adaptados as particularidades de cada projeto. Inicialmente, foram identificados, através de revisão sistemática da literatura, seis diferentes métodos para o agrupamento de componentes do produto em módulos. Dentre os métodos estudados, o método Modular Function Deployment (MFD), apresentou maior flexibilidade e abrangência nas atividades que compreendem o processo de modularização. Como resultado, propõe-se um método Modular Function Deployment Adapted, oferecendo as empresas uma orientação para configurar o MFD. Esta configuração proporciona uma aplicação do método customizada ao tipo de projeto desenvolvido pela empresa. O método é exemplificado para o caso de desenvolvimento de um equipamento estratégico em saúde, relacionado às atividades do Centro de Referência em Tecnologias de Equipamentos e Insumos Estratégicos para a Saúde CRETIES/UFRGS, visando favorecer a manutenção e a confiabilidade do equipamento por meio da modularização. / Modularization strategies have as objective the development of product architectures containing physically detachable units, called modules, so that these units may be used in variations of a product or in different product lines. However, that strategy ought to be planned during the Product Development Process (PDP), in which decisions to be taken will affect the whole life cycle of the product. With such purpose in mind, methods and techniques of modularization were created to support development teams. Those methods need to be adapted to the characteristics of each project, such as the kind of business and, the complexity and novelty of the product under development. Aiming at contributing to this research matter, this dissertation‘s general objective is to propose a restructuring of the modularization methods, adapted to different projects for the creation and evaluation of product concepts. First, by means of systematic literature review, six different methods were identified for grouping product components in modules. Within the studied methods, the Modular Function Deployment (MFD) method presented the greatest flexibility and comprehensiveness in activities that comprise the modularization process. As a result, a Modular Function Deployment Adapted method is proposed, offering guidelines to companies to adapt the MFD. Such adaptation provides a customized application of the method for the type of project developed by the company. The method is exemplified in the case of the development of a health device, related to the activities of the Centro de Referência em Tecnologias de Equipamentos e Insumos Estratégicos para a Saúde, CRETIES / UFRGS, aiming to promote the maintenance and equipment reliability through modularization.
28

Métodos de modularização no projeto conceitual de desenvolvimento de produtos

Sonego, Monique January 2013 (has links)
A estratégia de modularização tem como objetivo desenvolver arquiteturas de produto que contenham unidades fisicamente destacáveis, denominados módulos, de forma a permitir que estas unidades sejam utilizadas em variações de um produto ou em linhas de produtos diferentes. Essa estratégia deve ser planejada no Processo de Desenvolvimento de Produto (PDP), no qual são tomadas decisões que afetam todo o ciclo de vida do produto. Com esse propósito, métodos e técnicas de modularização foram criados para oferecer suporte às equipes de desenvolvimento. Estes métodos precisam ser adaptados às características de cada projeto, como a natureza do negócio, a complexidade e a novidade do produto desenvolvido. Para contribuir com esse tema de pesquisa, o objetivo geral desta dissertação é propor uma reestruturação de métodos de modularização para a criação e avaliação de conceitos, adaptados as particularidades de cada projeto. Inicialmente, foram identificados, através de revisão sistemática da literatura, seis diferentes métodos para o agrupamento de componentes do produto em módulos. Dentre os métodos estudados, o método Modular Function Deployment (MFD), apresentou maior flexibilidade e abrangência nas atividades que compreendem o processo de modularização. Como resultado, propõe-se um método Modular Function Deployment Adapted, oferecendo as empresas uma orientação para configurar o MFD. Esta configuração proporciona uma aplicação do método customizada ao tipo de projeto desenvolvido pela empresa. O método é exemplificado para o caso de desenvolvimento de um equipamento estratégico em saúde, relacionado às atividades do Centro de Referência em Tecnologias de Equipamentos e Insumos Estratégicos para a Saúde CRETIES/UFRGS, visando favorecer a manutenção e a confiabilidade do equipamento por meio da modularização. / Modularization strategies have as objective the development of product architectures containing physically detachable units, called modules, so that these units may be used in variations of a product or in different product lines. However, that strategy ought to be planned during the Product Development Process (PDP), in which decisions to be taken will affect the whole life cycle of the product. With such purpose in mind, methods and techniques of modularization were created to support development teams. Those methods need to be adapted to the characteristics of each project, such as the kind of business and, the complexity and novelty of the product under development. Aiming at contributing to this research matter, this dissertation‘s general objective is to propose a restructuring of the modularization methods, adapted to different projects for the creation and evaluation of product concepts. First, by means of systematic literature review, six different methods were identified for grouping product components in modules. Within the studied methods, the Modular Function Deployment (MFD) method presented the greatest flexibility and comprehensiveness in activities that comprise the modularization process. As a result, a Modular Function Deployment Adapted method is proposed, offering guidelines to companies to adapt the MFD. Such adaptation provides a customized application of the method for the type of project developed by the company. The method is exemplified in the case of the development of a health device, related to the activities of the Centro de Referência em Tecnologias de Equipamentos e Insumos Estratégicos para a Saúde, CRETIES / UFRGS, aiming to promote the maintenance and equipment reliability through modularization.
29

Métodos de modularização no projeto conceitual de desenvolvimento de produtos

Sonego, Monique January 2013 (has links)
A estratégia de modularização tem como objetivo desenvolver arquiteturas de produto que contenham unidades fisicamente destacáveis, denominados módulos, de forma a permitir que estas unidades sejam utilizadas em variações de um produto ou em linhas de produtos diferentes. Essa estratégia deve ser planejada no Processo de Desenvolvimento de Produto (PDP), no qual são tomadas decisões que afetam todo o ciclo de vida do produto. Com esse propósito, métodos e técnicas de modularização foram criados para oferecer suporte às equipes de desenvolvimento. Estes métodos precisam ser adaptados às características de cada projeto, como a natureza do negócio, a complexidade e a novidade do produto desenvolvido. Para contribuir com esse tema de pesquisa, o objetivo geral desta dissertação é propor uma reestruturação de métodos de modularização para a criação e avaliação de conceitos, adaptados as particularidades de cada projeto. Inicialmente, foram identificados, através de revisão sistemática da literatura, seis diferentes métodos para o agrupamento de componentes do produto em módulos. Dentre os métodos estudados, o método Modular Function Deployment (MFD), apresentou maior flexibilidade e abrangência nas atividades que compreendem o processo de modularização. Como resultado, propõe-se um método Modular Function Deployment Adapted, oferecendo as empresas uma orientação para configurar o MFD. Esta configuração proporciona uma aplicação do método customizada ao tipo de projeto desenvolvido pela empresa. O método é exemplificado para o caso de desenvolvimento de um equipamento estratégico em saúde, relacionado às atividades do Centro de Referência em Tecnologias de Equipamentos e Insumos Estratégicos para a Saúde CRETIES/UFRGS, visando favorecer a manutenção e a confiabilidade do equipamento por meio da modularização. / Modularization strategies have as objective the development of product architectures containing physically detachable units, called modules, so that these units may be used in variations of a product or in different product lines. However, that strategy ought to be planned during the Product Development Process (PDP), in which decisions to be taken will affect the whole life cycle of the product. With such purpose in mind, methods and techniques of modularization were created to support development teams. Those methods need to be adapted to the characteristics of each project, such as the kind of business and, the complexity and novelty of the product under development. Aiming at contributing to this research matter, this dissertation‘s general objective is to propose a restructuring of the modularization methods, adapted to different projects for the creation and evaluation of product concepts. First, by means of systematic literature review, six different methods were identified for grouping product components in modules. Within the studied methods, the Modular Function Deployment (MFD) method presented the greatest flexibility and comprehensiveness in activities that comprise the modularization process. As a result, a Modular Function Deployment Adapted method is proposed, offering guidelines to companies to adapt the MFD. Such adaptation provides a customized application of the method for the type of project developed by the company. The method is exemplified in the case of the development of a health device, related to the activities of the Centro de Referência em Tecnologias de Equipamentos e Insumos Estratégicos para a Saúde, CRETIES / UFRGS, aiming to promote the maintenance and equipment reliability through modularization.
30

Koncepční návrh elektrického výcvikového letounu / Conceptual design of training aircraft with electric propulsion

Seman, Matúš January 2018 (has links)
This thesis is focused on conceptual design of electric powered training aircraft, using certification guidelines CS-LSA. Designing process of geometrical and aerodynamic characteristics is primary based on statistics of certificated aircrafts in this particular category. The following calculation of performance stabilities and flight performances is based on knowledge of aerodynamic polar. The calculation of the polar is also part of this thesis. The last part of the thesis consists of construction design of the front part of fuselage and engine static structural analysis of engine mounts.

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