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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.
131

The Effects of Price Discrimination on Buyer¡¦s Internal Reference Price and Post-purchase Emotions

Huang, Siang-hua 30 June 2007 (has links)
This article examines whether price discrimination affects consumer price perceptions and emotions. Questionnaires involving various purchasing scenarios indicate that all kinds of price discrimination decrease the internal reference price of those who have to pay the original (higher) price. These effects of price discrimination on consumers¡¦ internal reference price are moderated by the discount depth. The deeper discount that the seller offers to the consumers, the larger the internal reference decreases. Further, when subjects were told that there is one consumer buy the product or service at the lower price (enjoying the price discount), they have negative emotion if they can have spend time looking for price-off coupons. But the other price discrimination such as VIP discount does not elicit consumers¡¦ negative emotion.
132

Design of model reference adaptive tracking controllers for uncertain dynamic systems

Teng, Chiu-Ju 23 June 2000 (has links)
Based on Lyapunov theorem, two different types of control schemes for solving robust tracking problems are presented in this thesis. The first one is model reference adaptive sliding mode control, which is designed for a class of SISO LTI systems with relative degree one possessing additive and multiplicative unstructured uncertainties in the input and output channels. By introducing a perturbation estimation process embedded in the proposed control scheme, the chattering phenomenon can be reduced effectively since only the perturbation estimation error needs to be overcomed. The second one is optimal model reference adaptive control, which is designed for a class of multi-input systems with input non-linearity. These systems are subject to model uncertainties and time-varying delay.
133

IC Design and Implementation of Preamplifier for 16 Mbps Infrared Receiver Module and Reference Clock Generator for DDR Synchronous Devices

Chen, Chi-Wen 15 June 2001 (has links)
Three different topics associated with their respective applications are proposed in this thesis. The first topic is the implementation of a transimpedence preamplifier for 16 Mbps infrared transceiver modules. The design of the preamplifier is aimed at the VFIR (very fast infrared) which is supposed to provide a 16 Mbps data transmission rate. The second topic is focused on the implementation of a robust reference clock generator design for DDR synchronous devices. A pulse generator circuit to generate pulses corresponding to the rise edges and fall edges of a given clock is presented. The third topic is to carry out a cost-effective voice dialer. It focuses on the voice feature extraction and the recognition of Chinese numbers 0 to 9. We present a low-cost method to implement such an algorithm by using 8051-ICE.
134

Digital Watermarking Methods for Image and Audio Signals

Chung, Mu-San 24 July 2001 (has links)
Encryption, digital signature and digital watermark are three popular methods to prevent a wide variety of multimedia products from illegal copy or subterfuge attacks. In particular, digital watermarking recently draws a lot of attention since it hides desirable information in transmitted audio, image and video data files without affecting much the data quality. The thesis proposes two watermarking methods for audio and image data. And both watermarking methods embed watermark signals in the spatial/time domain using a so-call Pixel Weight Table. The experiment results shows that the two methods have good performance. In addition, I propose a guantitive measuring method, called APSNR, to characterize the audio perceptual transparency.
135

Design of Discrete Variable Structure Controller

Lai, Rong-Chih 01 August 2001 (has links)
A simple technique of designing a robust discrete-time variable structure output tracking controller for a class of perturbed MIMO linear and nonlinear systems is proposed in this thesis. For linear systems, a model reference scheme is employed. Both an adaptive mechanism and a perturbation estimation process are embedded in the proposed control scheme. The information of the upper bound of the perturbation estimation error is not required due to the usage of adaptive mechanism. It is shown that the dynamics of the controlled systems will be driven into the vicinity of the designed switching surface, therefore the tracking error will be constrained in a small bounded region. Furthermore, the stability of the overall controlled system is guaranteed, and one can increase the tracking accuracy by adjusting the controller's parameters or by employing the perturbation estimation process.
136

Design of Model Reference Adaptive Tracking Controllers for Mismatched Uncertain Dynamic Systems

Chang, Chao-Chin 17 July 2002 (has links)
Based on the Lyapunov stability theorem, an optimal model reference adaptive control (OMRAC) scheme with perturbation estimation is presented in this thesis to solve robust tracking problems. The plant considered belongs to a class of MIMO perturbed dynamic systems with input nonlinearity and time varying delay in the state. The proposed control scheme contains three types of controllers. The first one is a linear feedback controller, which is an optimal controller if there is no perturbation. The second one is an adaptive controller, it is used for adapting the unknown upper bound of perturbation estimation error. The last one is the perturbation estimation mechanism. The property of uniformly ultimately boundness is proved under the proposed control scheme, and the effects of each design parameter on the dynamic performance is analyzed. Two numerical examples are given for demonstrating the feasibility of the proposed methodology.
137

Design of Model Reference Adaptive Tracking Controllers for Systems with Unstructured Uncertainties

Wu, Yi-Fen 08 January 2003 (has links)
Based on the Lyapunov stability theorem, a model reference adaptive variable structure control (MRAVSC) scheme with perturbation estimation is presented in this thesis for solving robust tracking problems. The plant considered belongs to a class of MIMO linear time invariant systems with arbitrary relative degree possessing additive and multiplicative unstructured uncertainties in the input and output channels. By introducing a perturbation estimation process embedded in the proposed control scheme, both the perturbations and differentials of tracking errors can be estimated. In addition, the proposed control scheme also contains an adaptive mechanism in order to automatically adapt the unknown upper bound of perturbation estimation error, and guarantee the property of uniformly ultimate boundedness for the closed-loop controlled system. Finally, two numerical examples are presented to demonstrate the feasibility of the proposed control scheme.
138

Development and assessment of electronic manual for well control and blowout containment

Grottheim, Odd Eirik 01 November 2005 (has links)
DEA ?? 63, Floating Vessel Blowout Control is a blowout containment study which was completed in 1990, and it did not include discussions about operations in the water depths we currently operate in. As offshore drilling is continuously moving into deeper and deeper waters, a need to further investigate well control and blowout containment in ultradeep water has arisen. This project describes the development and assessment of an electronic cross-reference tool for well control and blowout containment, with added focus on ultradeep water operations. The approach of this manual is fully electronic, thus being able to serve the needs of the engineer/driller with greater ease in both pre-planning and in a stressful onthe- job setting. The cross-reference is a manual for the state of the art in well control and blowout containment methodology. It provides easy-to-use topical organization by categories and subcategories, and aims at providing clear links between symptoms, causes, and solutions. Clear explanations to complicated issues are provided, and confirmation of applicable blowout intervention procedures, be it conventional or unconventional, are discussed. Human error and equipment failure are the causes of blowouts, and they are bound to happen in an ultradeep water environment. Well control events are harder to detect andhandle in ultradeep water, and quick reaction time is essential. After detection and shutin, the Driller??s method is the preferred circulation method in ultradeep water, due to its responsiveness and simplicity. In case kick handling is unsuccessful, contingency plans should be in place to handle a potential blowout. If a blowout does occur, and the blowing well does not self-kill through bridging, a dynamic kill through relief well intervention is likely to be necessary, as underwater intervention is difficult in ultradeep water. With new ultradeep water drilling technologies providing potential for increased performance, alternative well control methods might be necessary. Along with these new technologies follow new unfamiliar procedures, and proper education and training is essential.
139

Design of Adaptive Sliding Mode Controllers for Discrete-time Systems with Matched Perturbations

Hou, Guan-Yin 20 January 2008 (has links)
Based on the Lyapunov stability theorem, a methodology of designing robust discrete-time model reference variable structure state tracking controller is proposed in this thesis for a class of multi-input multi-output (MIMO) discrete-time systems. This variable structure controller is composed of three types of controllers. The first one is the feedback control law, which can eliminate the nominal term in the derivative of a Lyapunov function. The second one is the switching control law, which can determine the decreasing rate of the Lyapunov function. The third one is the adaptive control law, which is used to overcome the perturbations. The resultant robust variable structure controllers are capable of driving all the trajectories of tracking errors toward a small bounded region. The information of upper bound of the perturbation, which is not a constant and is dependent on the norm of state variable, is not required beforehand due to some adaptive mechanisms are embedded in the proposed control scheme, and the stability of the overall controlled system is guaranteed. A numerical example and a practical example are given to demonstrate the feasibility of the proposed control scheme.
140

Applications of CD-ROM technology for reference purposes a survey of reference librarians in libraries of four-year colleges and universities /

Pfarrer, Theodore Richard. January 1989 (has links)
Thesis (Ph. D.)--Florida State University, 1989. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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