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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

Aircraft systems design methodology and dispatch reliability prediction

Bineid, Mansour January 2005 (has links)
Aircraft despatch reliability was the main subject of this research in the wider content of aircraft reliability. The factors effecting dispatch reliability, aircraft delay, causes of aircraft delays, and aircraft delay costs and magnitudes were examined. Delay cost elements and aircraft delay scenarios were also studied. It concluded that aircraft dispatch reliability is affected by technical and non-technical factors, and that the former are under the designer's control. It showed that the costs of aircraft delays are very significant and must be reduced. Cont/d.
52

Innovative Design of Eight-Speed Parallel-Connected Automatic Transmissions for Automobiles

Kuo, Cheng-Sheng 10 September 2012 (has links)
An epicyclic-type automatic transmission is a device that is connected to the back of an engine and sends the power from the engine to the drive wheels. Its job is to keep the engine within a certain angular velocity. For the development of multi-speed parallel-connected automatic transmission for automobiles, the related configuration design methods are still tedious and prone to human error. Therefore, the purpose of this research is to present an efficient methodology for the systematic design of the parallel-connected automatic transmission for automobiles. First, fundamentals and gear-shifting operations of the parallel-connected automatic transmission are illustrated to establish the design requirements, and the theory of the analysis of speed ratios for epicyclic-type automatic transmission is derived based on the concept of lever analogy. Next, one simple clutching-sequence synthesis methods are proposed and illustrated, based on the lever analogy, and the design theory and the procedure of clutch configuration of epicyclic-type automatic transmission are developed. With the above methods, designs of six-speed and eight-speed parallel-connected automatic transmission. Finally, the complete atlas of six-speed and eight-speed parallel-connected automatic transmission can be systematically synthesized from the data of given speed ratios. This proposed design method can also be applied to the development and design of multi-speed parallel-connected automatic transmissions.
53

Aircraft systems design methodology and dispatch reliability prediction

Bineid, Mansour January 2005 (has links)
Aircraft despatch reliability was the main subject of this research in the wider content of aircraft reliability. The factors effecting dispatch reliability, aircraft delay, causes of aircraft delays, and aircraft delay costs and magnitudes were examined. Delay cost elements and aircraft delay scenarios were also studied. It concluded that aircraft dispatch reliability is affected by technical and non-technical factors, and that the former are under the designer's control. It showed that the costs of aircraft delays are very significant and must be reduced. Cont/d.
54

Development of a design methodology and application to advance the field of highly mobile robotics

Pace, Patrick Wayne 12 July 2011 (has links)
Developing innovative ideas as part of engineering design can be limited by the field of technology and the engineer's or design team's understanding of the field. Without sufficient understanding of an emerging technical field, ideation may be hampered by reinventing the proverbial wheel or by a lack of knowledge of the underlying physical principles and state of technology. The research presented here seeks to develop a tool and methodology intended to strengthen a designer’s or design team’s understanding of a field and relevant technologies in order to foster creative and innovative solutions. The presented inductive methodology consists of conducting a thorough review of existing relevant developing or commercially available technologies in order to obtain characteristic property data to be used as a basis of understanding. Analysis of the plotted data may lead to understanding existing trends, identifying voids where opportunities exist to expand the design space and general insights into the field. The effectiveness of using empirical data to look for innovation is investigated in the domain of highly mobile robots. Senior cadets from USAFA and UT Austin perform concept generation sessions before and after utilizing the proposed methodology to validate the effectiveness of the approach. The study at UT Austin validates the proposed methodology by measuring the quantity, quality, and novelty of the concepts generated before and after exposure to the methodology. These experiments demonstrate that state-of-technology design tools provide an effective foundation and platform for designers to generate a larger quantity of concepts. To further investigate the effectiveness of the proposed methodology, it is used to develop a device within the field of highly mobile robotics. There exist applications of highly mobile robots which require innovative solutions with regard to overcoming obstacles, payload capacity, energy storage and minimizing power requirements. The methodology allows for the development of innovative concepts, and the embodiment and manufacture of a particular solution. The mechanical design solutions to multiple design challenges are presented, and the prototyped device proves capable of expanding the existing design space in terms of its performance with respect to the metrics mentioned above. / text
55

Supporting the Use of Causally Related Functions in Biomimetic Design

Cheong, Hyunmin 07 January 2014 (has links)
Biomimetic design uses biological analogies to produce innovative engineering solutions. However, designers face challenges in identifying useful biological analogies and correctly applying the analogies identified to design solutions. To overcome these challenges, this thesis proposes the use of causally related functions in biomimetic design. Causally related functions describe how a desired function is enabled by another function. To support the use of causally related functions, a set of tools was developed. First, the causal relation template and mapping techniques (one-to-one mapping instructions and problem-independent scenario mapping) were devised to assist designers to identify and apply causally related functions from descriptions of biological phenomena. In pen-and-paper experiments with senior undergraduate engineering students, the causal relation template, if used correctly, facilitated the development of design concepts that were analogous to biological phenomena provided as sources of analogy. In addition, the mapping techniques reduced the percentage of participants who made non-analogous associations from biological phenomena to develop design concepts. Another tool developed was the causal relation retrieval method. The method uses syntactic information in natural language sentences to explicitly identify causally related functions. A modified verbal protocol study with graduate engineering students revealed that the retrieval method increased the likelihood of locating biological phenomena relevant to given design problems compared to a single verb-keyword search method. Also, the search matches located with the retrieval method were more likely to facilitate functional association to develop design concepts. These results demonstrate that the knowledge structure of causally related functions can support both the identification of relevant biological phenomena in natural language text and use of analogical reasoning between the biological phenomena and design solutions. The causal relation template and mapping strategies developed contribute to the field of biomimetic design as training methods for designers; and the causal relation retrieval method could serve a technique to bridge the gap between the natural language approach and the modeling approach to biomimetic design.
56

Supporting the Use of Causally Related Functions in Biomimetic Design

Cheong, Hyunmin 07 January 2014 (has links)
Biomimetic design uses biological analogies to produce innovative engineering solutions. However, designers face challenges in identifying useful biological analogies and correctly applying the analogies identified to design solutions. To overcome these challenges, this thesis proposes the use of causally related functions in biomimetic design. Causally related functions describe how a desired function is enabled by another function. To support the use of causally related functions, a set of tools was developed. First, the causal relation template and mapping techniques (one-to-one mapping instructions and problem-independent scenario mapping) were devised to assist designers to identify and apply causally related functions from descriptions of biological phenomena. In pen-and-paper experiments with senior undergraduate engineering students, the causal relation template, if used correctly, facilitated the development of design concepts that were analogous to biological phenomena provided as sources of analogy. In addition, the mapping techniques reduced the percentage of participants who made non-analogous associations from biological phenomena to develop design concepts. Another tool developed was the causal relation retrieval method. The method uses syntactic information in natural language sentences to explicitly identify causally related functions. A modified verbal protocol study with graduate engineering students revealed that the retrieval method increased the likelihood of locating biological phenomena relevant to given design problems compared to a single verb-keyword search method. Also, the search matches located with the retrieval method were more likely to facilitate functional association to develop design concepts. These results demonstrate that the knowledge structure of causally related functions can support both the identification of relevant biological phenomena in natural language text and use of analogical reasoning between the biological phenomena and design solutions. The causal relation template and mapping strategies developed contribute to the field of biomimetic design as training methods for designers; and the causal relation retrieval method could serve a technique to bridge the gap between the natural language approach and the modeling approach to biomimetic design.
57

Using Surrealism to create screen printed textile designs for a clothing line

Birk, Valerie J. January 1999 (has links)
The purpose of this creative project was to create a functional and aesthetically pleasing line of garments. The goals of this project were to: 1) produce three textile designs (motifs), 2) screen print the textile designs on fabric, and 3) design and construct a functional/aesthetically pleasing garment line using the three original textile motifs. There were several processes involved in creating the end result. The processes involved in this project were designing a motif for fabric, screen printing the designs on to the fabric, and designing and constructing the clothing line.The work of three artists from the Surrealism movement in art history were used as a source of inspiration for designing the motifs printed on the fabric. The three artists were Joan Miro, Salvador Dali and Max Ernst.The images of the motifs were first sketched and redrawn on the MicroDesign I Cad system. The motifs were printed on 100% cotton using the stencil process in screen printing. Five alternating colors were used to print the three different images. After the fabric was printed, three garment designs were created to be constructed using the new fabric. The patterns for the garments were created using the draping method for pattern making.The results of the project were favorable. The fun spirited motifs represented the feel of the Surrealist movement. The completed garments looked like the original illustrations. Although much was achieved through this project, it far exceeded the time expectations for completion. / Department of Family and Consumer Sciences
58

Towards decision support for complex system architecture design with innovation integration in early design stages

Moullec, Marie-Lise 24 January 2014 (has links) (PDF)
The aim of this research work is to propose a method allowing innovation integration in early design stages and supporting architecture design of complex systems that have significant implications for the rest of overall system life-cycle. Focusing on system architectures generation support, this method proposes to use Bayesian networks combined with Constraint Satisfaction Problem (CSP) techniques in order to semi-automatically generate and evaluate complex systems architectures. Bayesian network model is used to represent the design problem in terms of decision variables, constraints and performances. Furthermore, an architecture generation algorithm is proposed to generate feasible solutions and to cluster them with regard to a given confidence level threshold. This confidence level is representing the estimation of the uncertainty on the overall system. Estimation of architecture performances are also calculated within the Bayesian network. Once the system architectures are generated, a CSP model optimises the component placement regarding placement constraints and optimisation objectives defined by designers. Software has been developed for the purpose of problem modelling and solutions visualisation. Two industrial implementations yielded in a generation of a high number of architecture solutions. In order to test the feasibility of architecture selection in an industrial environment, a study was conducted integrating four system designers. This study underlined the difficulties in defining architecture selection criteria and provides recommendations for the future system architecture selection support.
59

The conceptual structure of product semantic models

Hughes, Richard Sylvester January 1999 (has links)
The study is concerned with the conceptual structure and content of the framework for characterising user-product interaction, proposed under the title – ‘Product Semantics’. The sources for the critique of design, from which the framework is derived, are identified and analysed, and the substantive theoretical and methodological content given initial consideration in terms of the deployment of the central concept of ‘meaning’, and the principal theoretical approaches adopted in the analysis of meaning and semantic concepts generally. The commitment to a cognitive and experiential approach to user-interaction is established and the concepts central to the framework, and requiring more detailed analysis, are identified. The core of the study consists in an analysis of the sequence of concepts and contexts that are chiefly used in the theoretical articulation of the framework, including - function, affordance, categorisation, artefacts, meaning and expression - of which the concept of affordance is central to the structure. On the basis of the initial consideration of the structure and content of the scheme, and in the light of the analysis of concepts, the explanatory structure of the framework is established. It is argued that the core commitment to an experiential and cognitive account, and the form of the explanatory structure, are jointly incompatible with the conceptual content of the framework, particularly in respect of the pivotal role of the concept of affordance. Proposals are advanced for an alternative interpretation which addresses the central issues of consistency and coherence, and which suggests an alternative approach to the conceptual characterisation of the framework and the form of the explanatory hierarchy. The implications of the framework, and the proposed alternative interpretation, are considered in respect of their application in shaping approaches to the development of design theory and methodology, and the experiential aspect of semantics and cognition.
60

Mu-Tonics: in search of mutable tectonics

Ong, Lorraine Grace G. 09 April 2007 (has links)
In search of mutable tectonics is a research investigation linking principles found in natural systems, investigated by various fields in biology, physics, and mathematics, in the creation of a design methodology in Architecture. Specifically the report looks into natural system with packing and stacking strategies like bone formation, foam or soap bubbles, and sphere packing. Rules and physical observations of the natural are carried forward in the development of a topological language, through digital investigations, which define relationships between variations in spatial configurations and structural members. What we hope to achieve here is that by studying natural systems already realized in the natural world a more adaptive system of design between form, structure and space is immediately established; resulting in the discovery of emergent spaces which intrinsically conveys an emergent structural system and vise versa. The outcome is the creation of an adaptive networked process in the design formulation in Architecture.

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