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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.
51

Design of A Therapeutic Light Device Using Kano’s Model and A Decision-making Method Based on HOQ

Feng, Bohan 07 February 2014 (has links)
In this research, a therapeutic light device is developed based on customer requirements. The quality function deployment (QFD) is initially used to transfer customer requirements to design parameters. However, several inherent shortcomings of QFD method are identified based on the design evaluation and the customer feedback of the initially proposed model. In the process of improving the initial model, the correlation information is used in ranking technical measurement and components. A decision-making method is proposed to generate an optimal model for the selection of appropriate components. Kano’s model is applied to enhance the customer’s requirement of “good looking”. The result shows that the improved model satisfies the customer with good overall performance.
52

Applying inventive problem solving methods at the early stage of industrial product design

Bercsey, Tibor, Nagy, Klaudia 05 June 2018 (has links) (PDF)
The paper introduces a methodological overview followed by thoughts of the recent problems of using these theories at the industrial ground offering some solutions for improvement. Shows a case study where several semesters of the Integrated Product Design courses were observed at the Department of Machine and Product Design at the Budapest University of Technology and Economics (BME). The aim of the presented study has been to evaluate a selected product design project from the aspect of the effectiveness of the previous methodological training. Based on these findings we provide some suggestions for the design education to support the early stage of the design process. [...from the introduction]
53

Environmentally conscious design : an economic life cycle approach

Rose, Elliot P. January 1997 (has links)
Companies are under increasing pressure to deal with environmental concerns during product design, for it is the design process which primarily decides the environmental impact of a manufactured product over its life. Tools which assist in taking a life cycle view of the product are a necessary support to designers. Prime amongst these tools is Life Cycle Assessment (LCA). However, a major criticism of LCA methodologies is that while they provide advice on environmentally superior product designs, they do not provide guidance on the economic impact. With product take back increasingly likely to become the responsibility of producer companies attention is now being paid to the later phases of a products life, such as maintenance and disposal costs. A new methodology is shown to be required to complement LCA, one which considers the economic implications of environmentally superior designs over the whole product life. It is argued that a major challenge of such a methodology will be how it deals with the uncertainty associated with the future. The research provides a review of product life cycle design methodologies and a critique of existing approaches to uncertainty. A design teams requirements for decision support that deals with product economic life cycle uncertainty is presented and a decision support methodology which meets these requirements is described. The methodology builds upon the theory of life cycle costing. In practice, the methodology integrates a computer based life cycle model with statistical techniques to quantify the contribution of life cycle variables. In bringing these proven but previously separate tools together the method resolves the issue of uncertainty in a novel and acceptable way. Through the use of an in-depth industrial case study, it is shown that the methodology provides practical support to the design team to produce economically superior product life cycle designs.
54

O design e a consciência da sustentabilidade integral : o projeto Tamar na Vila Regência, ES /

Silveira, Cristiane Gianezi da. January 2011 (has links)
Orientador: Olympio José Pinheiro / Banca: Ivan Amaral Guerrini / Banca: Cláudio Roberto Goya / Resumo: O atual modelo de produção, distribuição e consumo que orienta nossa sociedade é apontado como responsável por severos prejuízos ao planeta, aos seus recursos naturais e a todas as espécies vivas além de favorecer a marginalização e a massificação das culturas. A sustentabilidade surge, nesse cenário, como uma tentativa de reverter ou pelo menos minimizar esse quadro, através da incorporação do pensamento sistêmico e de metodologias transdisciplinares que propõem novos modelos de comportamento. Este estudo visa tragar um panorama do surgimento dos conceitos de ambientalismo e de sustentabilidade e apresenta exemplos que apontam como ela é percebida e praticada pela população no Brasil. Neste processo de investigação, focalizou-se como estudo de campo a atuação do Projeto Tamar, que busca a preservação ambiental através da conscientização e desenvolvimento social, feito um recorte na Vila de Regência, litoral norte do Espírito Santo, onde se avaliou a importância do artesanato para a melhoria da qualidade de vida local. Observando este amplo contexto da produção ao consumo, tanto no que diz respeito à preservação do meio ambiente quanto ao desenvolvimento social, podemos destacar o design como ferramenta indispensável na busca por uma "ecocivilização", termo utilizado por Azevedo (2008). Devido à influência direta na relação projeto, produção, venda e consumo, o designer é um dos pilares que deverá estruturar a tão sonhada sociedade sustentável em uma ecocivilização. os resultados que foram pesquisados sinalizam que ainda há um grande abismo entre as preocupações sócio-ambientais e o real comportamento do ser humano global e particularmente do brasileiro. Como consequencia, defende-se que atuar somente na produção e no consumo já não é suficiente para o campo do Design... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The current model production, distribuition and consumption that drives our society is blamed for severe damage to the planet, to its natural resources and to all living species in addition to pormote marginalization and cultural excavation. The sustainability arises in this scenario as an attempt to reverse or at least minimize this framework through the incoporation of systems thinking and methodologies of transdiciplinary, which propose new models or bahavior. This study aims to give an aims to give an overwiew of the emergence of the concepts of environmentalism and sustainability, and provides examples that show how it is perceived and practiced by the population in Brazil. In the process of research has focused field study as the Tamar Project, which seeks to protect the environment through awareness and social development, we studied in specific the Regência Village, north coast of the Espírito Santo, where we evaluated the importance of the craft work to improve the local quality of life. Noting this broad context from production to consumption, both with regard to environmental preservation and social development, we highlight the design as a tool in the search for a indispensável "ecocivilization", a term used by Azevedo (2008). Due to the direct influence on relationship design, produciton, sale and consumption, the designer is one of the pillars that should structure our longed for a sustainable society in ecocivilization. The results that were surveyed indicate that there is still a big gap in socio-environmental concerns and real human behavior overall and particularly Brazil. As a result, it is argued that only act in the production and consumption is no longer sufficient for the field of design, since designers must, above all, assuming the role of educating for a new consciousness on a planetary scale / Mestre
55

Development and analysis of hierarchical feedforward neural network systems for classification of motor neurone disease based on magnetic resonance spectra

Refaee, Mohamed January 2001 (has links)
Possible changes in brain metabolites are associated with Motor Neurone Disease (MND). Magnetic Resonance Spectroscopy (MRS) has been performed on the brains of MND patients and control volunteers to acquire signals which contain information about brain metabolites from within the motor cortex area. Discrimination between JvThD and normal groups may help to understand the pathogenic mechanisms in MND and may be useful for monitoring the effects of future trial treatment regimens. The research described in this thesis presents the development of a pattern recognition system based on neural networks to correctly distinguish between motor neurone disease (MND) patients and controls when presented with a nuclear magnetic resonance (NMR) spectrum. The NMR spectra are pre-processed to obtain consistent data, and statistical parameters are extracted and selected from each spectrum. Four statistical neural network classifiers are used to provide information and initial decisions (MND/normal). A neural network is then used to combine these to give a final decision. Experimental results indicate that the system can achieve high performance classification on the spectra, including spectra not seen by the system during training. The experiment was repeated on different training and test sets to validate the method and the repeated design shows that the final system was able to achieve high performance classification. A ifizzy rule-based system teclmique is applied to translate and extract rules encoded in weights of neural network classifiers. The neural networks are translated into a few comprehensible rules to understand how the network performs the final decision.
56

Machine vision system developments for industrial inspection applications

Field, Matthew January 1997 (has links)
This thesis describes research in the area of automated industrial inspection using machine vision systems. It is anticipated that the algorithms described will contribute to the design of a machine vision system for the automatic surface inspection of cylindrical pellets. Firstly, the acquisition and segmentation of pellet tray images using area capture is described. Individual pellets are segmented from a pellet tray image by a novel system using the Radon transform coupled with data clustering. Subsequent to the segmentation, the linking of four pellet views depicting the entire circumferential area of the pellet is described along with a simple technique to compensate for intensity variations brought about by imaging the three-dimensional cylindrical surface of the pellet. The image processing techniques of filtering, edge detection, thresholding and morphology are used in the segmentation of grey level pellet defect images. The grey level pellet images are low-pass filtered and binary images formed using edge detection with thresholding. Binary morphology operators are then used in conjunction with a termination condition based on the number of objects in the image to ensure homogenous defect representations. The problem of overlapping defects is addressed, resulting in a second algorithm using the Radon transform coupled with data clustering. Prior to classification salient features are extracted from a set of synthetic binary defect images to form feature vectors. The novel idea of image object classification using 100% fuzzy inference is described, and results are shown to be superior to results obtained by feature space classifiers. The sub-classification of crack defects is carried out using a heuristic classifier, and the parameterisation of pellet defects is described.
57

Lossy compression of speech using perceptual criteria

O'Donnell, Michael January 1998 (has links)
The research contained in this thesis provides an investigation into a new method of minimising the perceptual differences when encoding digitised speech. An application of the perceptual criteria is described in the context of a codebook encoding methodology Some of the background studies covered aspects of psychoacoustics, in particular the effects of the human outer, middle and inner ear. Models approximating each region of the ear are utilised and concatenated into a single overall auditory response path model. As the objective of the research is to encode and decode speech waveforms, some study into how speech is produced and the classification of speech sounds is required. From this there is a description of a basic speech production model which is modelled as a digital filter. A review of the main categories for coding schemes that are currently employed is presented along with commonly used coding methods. In particular the codebook coding method is reviewed in sufficient detail to contrast with the new coding method. The development of a new perceptual minimisation criterion which relies on dual application of the auditory response path model on the original and reconstructed speech waveforms is described. In this the ordering of eodebook searches, the frequency spectrum used as the search target, windowing functions with durations and placement are all analysed to determine the optimum encoder design. Also described are a number of prospective gain algorithms which cover both time and frequency domain implementations. A new encoder is constructed which fully integrates the new perceptual criterion into the minimisation of the original and reconstructed speech waveforms. In the minimisation no part of the traditional encoder method is used, however both methods use a similar technique for determining gain factors. Speech derived from both encoders was subjectively assessed by a number of untrained, independent listeners. The results presented show that both methods are comparable but there is a slight preference towards the traditional encoder. A measure of the complexity indicated that the new minimisation method is also more complex than the traditional encoder.
58

Spherical mosaic construction using physical analogy for consistent image alignment

Gonzalez, Manuel Guillen January 1999 (has links)
The research contained in this thesis is an investigation into mosaic construction. Mosaic techniques are used to obtain images with a large field of view by assembling a sequence of smaller individual overlapping images. In existing methods of mosaic construction only successive images are aligned. Accumulation of small alignment errors occur, and in the case of the image path returning to a previous position in the mosaic, a significant mismatch between nonconsecutive images will result (looping path problem). A new method for consistently aligning all the images in a mosaic is proposed in this thesis. This is achieved by distribution of the small alignment errors. Each image is allowed to modify its position relative to its neighbour images in the mosaic by a small amount with respect to the computed registration. Two images recorded by a rotating ideal camera are related by the same transformation that relates the camera's sensor plane at the time the images were captured. When two images overlap, the intensity values in both images coincide through the intersection line of the sensor planes. This intersection line has the property that the images can be seamlessly joined through that line. An analogy between the images and the physical world is proposed to solve the looping path problem. The images correspond to rigid objects, and these are linked with forces which pull them towards the right positions with respect to their neighbours. That is, every pair of overlapping images are "hinged" through their corresponding intersection line. Aided by another constraint named the spherical constraint, this network of selforganising images has the ability of distributing itself on the surface of a sphere. As a direct result of the new concepts developed in this research work, spherical mosaics (i.e. mosaics with unlimited horizontal and vertical field of view) can be created.
59

Mycelium: Growing materialsexperience : A study on improving the appearance of mycelium-composites through a material driven design process

Andersson, Frida January 2022 (has links)
Mycelium-composites has been emerging commercially as an environmentally sustainable alternative to conventional materials. By utilizing the fungal mycelium’s ability to bond with lignin and cellulose fibers of plants, mycelium-composites can be made that are recyclable and renewable. Mycelium therefore has the potential to contribute to creating more sustainable options in material selection for product designers. However, the visual appearance of mycelium materials might pose a challenge when it comes to their adaption into society. Case-studies have indicated a negative reaction to the mycelium-composites aesthetics which are characterized by imperfections and irregularities with an off-white coloring. Using theories surrounding aesthetics, materials experience and emotional design, the purpose of this study was to further develop the visual and/or aesthetical aspects of a mycelium-composite through a material driven design process The results of material development is presented in a product concept that displays the insight that can assist designers create mycelium-based products that are more accepted by a broader market.
60

Process Modeling of Next-Generation Liquid Fuel Production - Commercial Hydrocracking Process and Biodiesel Manufacturing

Chang, Ai-Fu 12 October 2011 (has links)
This dissertation includes two process modeling studies -- (1) predictive modeling of large-scale integrated refinery reaction and fractionation systems from plant data – hydrocracking process; and (2) integrated process modeling and product design of biodiesel manufacturing. \r\n1. Predictive Modeling of Large-Scale Integrated Refinery Reaction and Fractionation Systems from Plant Data -- Hydrocracking Processes: This work represents a workflow to develop, validate and apply a predictive model for rating and optimization of large-scale integrated refinery reaction and fractionation systems from plant data. We demonstrate the workflow with two commercial processes -- medium-pressure hydrocracking unit with a feed capacity of 1 million ton per year and high-pressure hydrocracking unit with a feed capacity of 2 million ton per year in the Asia Pacific. This work represents the detailed procedure for data acquisition to ensure accurate mass balances, and for implementing the workflow using Excel spreadsheets and a commercial software tool, Aspen HYSYS from Aspen Technology, Inc. The workflow includes special tools to facilitate an accurate transition from lumped kinetic components used in reactor modeling to the boiling point based pseudo-components required in the rigorous tray-by-tray distillation simulation. Two to three months of plant data are used to validate models' predictability. The resulting models accurately predict unit performance, product yields, and fuel properties from the corresponding operating conditions.\r\n2. Integrated Process Modeling and Product Design of Biodiesel Manufacturing: This work represents first a comprehensive review of published literature pertaining to developing an integrated process modeling and product design of biodiesel manufacturing, and identifies those deficient areas for further development. It also represents new modeling tools and a methodology for the integrated process modeling and product design of an entire biodiesel manufacturing train. We demonstrate the methodology by simulating an integrated process to predict reactor and \r\nseparator performance, stream conditions, and product qualities with different feedstocks. The results show that the methodology is effective not only for the rating and optimization of an existing biodiesel manufacturing, and but also for the design of a new process to produce biodiesel with specified fuel properties. / Ph. D.

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