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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.
11

Study of Ultrasonic Treatment of Clostridium on Bio-hydrogen Producing Effect

Kuo, Huan-Chen 29 August 2012 (has links)
The resources on earth are limited; thus, the demand for energy, goods and materials is surging because of the growth of the advanced technology and population. The issues of using the resources effectively and changing them into a useful energy are then important. Taiwan creates a vast amount of agricultural waste every year. The traditional way of eliminating the agricultural waste would be burned and buried. However, it is not only the agricultural waste cannot be reused and recycled, but also the problem of air pollution occurred. The objectives of this thesis are thus to transfer the agricultural waste into a useful energy. This study contents two parts. The first part changes the agricultural waste into sugar. The agricultural waste is full of wood fiber and can be transformed to sugar by a microorganism method. A cane which is a common agricultural waste is used; the wood fiber in cane will be added to the thermostable cellulolytic bacterial Geobacillus thermoleovorans T4 isolated from sugar refinery wastewater in southern Taiwan. T4 can convert wood fiber into sugar. Experimental results showed that the rate of reducing sugar is 13.77%. The second part studies the biological hydrogen production by Clostridium acetobutylicum ATCC 824, and the sugar will be added into the process. Also, this study uses ultrasonic treatment in the biological hydrogen production and calculates the natural frequency of ATCC 824. The experiment is designed using the Taguchi method for increasing hydrogen production, hydrogen production rate and hydrogen production efficiency by using an ultrasonic treatment to treat C. acetobutylicum ATCC 824. It is showed that the best combination is temperature 37¢XC, ultrasonic frequency 0.5 MHz, ultrasonic intensity 136 mW/cm2, exposure time 10 s, pH 7.5 and bacterial concentration 20%. This study can apply in bio-energy and fermentation food producing.
12

A Study of Process Parameter Optimization for BIC Steel

Tsai, Jeh-Hsin 06 February 2006 (has links)
Taguchi methods is also called quality engineering. It is a systematic methodology for product design(modify) and process design(improvement) with the most of saving cost and time, in order to satisfy customer requirement. Taguchi¡¦s parameter design is also known as robust design, which has the merits of low cost and high efficiency, and can achieve the activities of product quality design, management and improvement, consequently to reinforce the competitive ability of business. It is a worthy research course to study how to effectively apply parameter design, to shorten time spending on research, early to promote product having low cost and high quality on sale and to reinforce competitive advantage. However, the parameter design optimization problems are difficult in practical application owing to (1)complex and nonlinear relationships exist among the system¡¦s inputs, outputs and parameters and (2)interactions may occur among parameters. (3)In Taguchi¡¦s two-phase optimization procedure, the adjustment factor cannot be guaranteed to exist in practice. (4)For some reasons, the data may become lost or were never available. For these incomplete data, the Taguchi¡¦s method cannot treat them well. Neural networks have learning capacity fault tolerance and model-free characteristics. These characteristics support the neural networks as a competitive tool in processing multivariable input-output implementation. The successful field including diagnostics, robotics, scheduling, decision-marking, predicition, etc. In the process of searching optimization, genetic algorithm can avoid local optimization. So that it may enhance the possibility of global optimization. This study had drawn out the key parameters from the spheroidizing theory, and L18, L9 orthogonal experimental array were applied to determine the optimal operation parameters by Signal/Noise analysis. The conclusions are summarized as follows: 1. The spheroidizing of AISI 3130 used to be the highest unqualified product, and required for the second annealing treatment. The operational record before improvement showed 83 tons of the 3130 steel were required for the second treatment. The optimal operation parameters had been defined by L18(61¡Ñ35) orthogonal experimental array. The control parameters of the annealing temperature was at B2
13

Analysis of dynamic robust design experiment and modeling approach for degradation testing

Bae, Suk Joo, January 2003 (has links) (PDF)
Thesis (Ph. D.)--School of Industrial and Systems Engineering, Georgia Institute of Technology, 2004. Directed by Paul H. Kvam. / Vita. Includes bibliographical references (leaves 108-113).
14

Robust design goal formulations and metamodeling techniques

Lin, Yao 08 1900 (has links)
No description available.
15

A robust concept exploration method for configuring complex systems

Chen, Wei 08 1900 (has links)
No description available.
16

A design of experiment approach to tolerance allocation

Islam, Ziaul. January 1995 (has links)
Thesis (M.S.)--Ohio University, June, 1995. / Title from PDF t.p.
17

Using the Taguchi design and central composite design to increase the robustness of a process from its raw material variability

Cuevas Salcido, Alvaro, January 2009 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
18

A systematic, experimental methodology for design optimization

Ritchie, Paul Andrew, 1960- January 1988 (has links)
Much attention has been directed at off-line quality control techniques in recent literature. This study is a refinement of and an enhancement to one technique, the Taguchi Method, for determining the optimum setting of design parameters in a product or process. In place of the signal-to-noise ratio, the mean square error (MSE) for each quality characteristic of interest is used. Polynomial models describing mean response and variance are fit to the observed data using statistical methods. The settings for the design parameters are determined by minimizing a statistical model. The model uses a multicriterion objective consisting of the MSE for each quality characteristic of interest. Minimum bias central composite designs are used during the data collection step to determine the settings of the parameters where observations are to be taken. Included is the development of minimum bias designs for various cases. A detailed example is given.
19

Taguchi methods in internal combustion engine optimisation

Green, Jeremy James 12 1900 (has links)
Thesis (MScEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Statistical experimental design techniques are powerful tools that are often approached with suspicion and apprehension by experimenters. The trend is to avoid any statistically structured and designed experimentation program, and to rather use the traditional method of following ones "gut feel". This approach, more often than not, will supply a satisfactory solution, but there is so much more information availablefor the same amount of effort. This thesis strives to outline the method and application of the Taguchi methodology of experimental design. The Taguchi method is a practical, statistical experimental design technique that does not rely on the designer's knowledge of the complex statistics typicallyneeded to design experimental programs, a fact that tends to exclude design of experiments from the averageengineers' toolbox. The essence of the statistical design of experiments is this: The traditional method of varying one variable at a time and investigating its effect on an output is no longer sufficient. Instead all the input variables are varied at the same time in a structured manner. The output trends resulting from each input variable are then statisticallyextracted from the data in the midst of the variation. Taguchi method achieves this by designing experiments where every level of every input variable occurs an equal number of times with every level of every other input variable. The experimental designs are represented in orthogonal arrays that are chosen and populated by the experimenter by following a simple procedure. Four case studies are worked through in this text and, where possible, compared to the "traditional" approach to the same problem. The case studies show the additional information and time savings availablewith the Taguchi method, as well as clearlyindicating the importance of using a stable system on which to do the experiments. The Taguchi method generated more information in fewer experiments than the traditional approaches as well as allowing analysis of problems too complex to analysewithout a statisticaldesign of the experimentation procedure. / AFRIKAANSE OPSOMMING: Statistiese eksperimentele ontwerptegnieke is besonder kragtige instrumente wat baie keer met agterdog deur ekspermenteerders beheen word. Die neiging is om enige statistiese gestruktureerde and ontwerpte eksperimentele program te vermy, en om liewer die tradisionele metode, wat op 'n mens se intuïsie staatmaak, te gebruik. Hierdie benadering sal baie keer 'n bevredigende oplossing gee, maar daar is veel meer inligting vir dieselfde hoeveelheid inspanning verkrygbaar, wanneer die Taguchimetode gebruik word. Hierdie tesis strewe om die metode en toepassing van die Taguchimetodologie van eksperimentele ontwerp voor te lê. Die Taguchimetode is 'n praktiese statistiese eksperimentele ontwerptegniek .wat nie op die ontwerper se kennis van komplekse statistiek om eksperimentele programme te ontwerp berus nie. Hierdie komplekse statistiek neig ook om eksperimentele ontwerp van die gemiddelde ingenieursvaardigehede uit te sluit. Die kern van statistiese eksperimentele ontwerp is die volgende: Die tradisionele metode van een veranderlike op 'n slag te varieer om die effek op die uitset te ondersoek, is onvoldoende. In plaas daarvan, word al die insetveranderlikes gelyktydig gevarieer in 'n gestruktureered manier. Die neigings van elke veranderlike is dan statisties ontleed van die data ten midde van die variasie van al die ander veranderlikes. Die Taguchimetode bereik die ontwerpte eksperimente deur elke vlak van elke insetveranderlik in 'n gelyke aantal keer met elke vlak van elke ander insetveranderlike te varieer. Hierdie is verteenwoordig deur ortogenale reekse wat gekies en gevul is deur 'n eenvoudige wisselpatroon te volg. Vier gevallestudies is deurgewerk en, waar moontlik, vergelyk met die tradisonele siening van dieselfde probleem. Die gevallestudies wys hoe toereikbaar die additionele inligting in die Taguchimethode toepassings is. Hulle beklemtoon ook die belangrikheid van 'n stabiele sisteem waarop die eksperimente berus. Die Taguchimetode het meer inligting verskaf met minder eksperimente as die tradisionele toenaderings, en ook toegelaat dat die analise van probleme, te kompleks om te analiseer sonder om 'n statistiese ontwerp van eksperimentele prosedure te volg, opgelos kon word.
20

Observation-driven configuration of complex software systems

Sage, Aled January 2004 (has links)
The ever-increasing complexity of software systems makes them hard to comprehend, predict and tune due to emergent properties and non-deterministic behaviour. Complexity arises from the size of software systems and the wide variety of possible operating environments: the increasing choice of platforms and communication policies leads to ever more complex performance characteristics. In addition, software systems exhibit different behaviour under different workloads. Many software systems are designed to be configurable so that policies (e.g. communication, concurrency and recovery strategies) can be chosen to meet the needs of various stakeholders. For complex software systems it can be difficult to accurately predict the effects of a change and to know which configuration is most appropriate. This thesis demonstrates that it is useful to run automated experiments that measure a selection of system configurations. Experiments can find configurations that meet the stakeholders' needs, find interesting behavioural characteristics, and help produce predictive models of the system's behaviour. The design and use of ACT (Automated Configuration Tool) for running such experiments is described, in combination a number of search strategies for deciding on the configurations to measure. Design Of Experiments (DOE) is discussed, with emphasis on Taguchi Methods. These statistical methods have been used extensively in manufacturing, but have not previously been used for configuring software systems. The novel contribution here is an industrial case study, applying the combination of ACT and Taguchi Methods to DC-Directory, a product from Data Connection Ltd (DCL). The case study investigated the applicability of Taguchi Methods for configuring complex software systems. Taguchi Methods were found to be useful for modelling and configuring DC-Directory, making them a valuable addition to the techniques available to system administrators and developers.

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