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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.
581

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

Lin, Yu-ching 09 April 2007 (has links)
In this thesis a model reference adaptive sliding mode control scheme is proposed for a class of linear time-invariant MIMO systems with unstructured and input, output uncertainties to solve the robust tracking problems. The designing of the proposed control scheme is divided into three steps. The first step is to design the sliding functions, the second step is to construct the estimators of the lumped perturbation. These estimators are able to estimate the derivatives of the tracking errors. The third step is to design the adaptive sliding mode controller. The proposed control scheme is designed without requiring the information of the upper bound of perturbations, and guarantee the stability of the controlled system. In fact the asymptotical stability can be achieved for some special cases. Finally, three numerical examples are presented to demonstrate the feasibility of the proposed control scheme.
582

creativity in advertisement and the influences of message that advertisement appeals toward consumer¡¦s interest

chang, shu-chen 20 July 2007 (has links)
Abstract Competitions between the brands of the real estate commodity are intense. With regard to sales, the advertisement must bring into full play in the marketing situation which engages in hand-to-hand combat. Goal of the creativity person in message designs of the advertisement is trying to have the consumers sharing same feeling. Allow the advertising creativity has more accurate effect, the appeal strategy complement each other reduces the advertisement being invalid and waste. This research is aimed at the advertisement of the real estate. It is to discuss what level does combination influence of the advertising creativity and the advertising appeals have effect on the consumer¡¦s interest in product. There are two goals in this research, first is to discuss combination influence of the advertising creativity and the advertising appeal. How advertising creativity high-low level, different advertisement combinations of perceptual appeal and rational appeal show their effects. Second is to discuss how the consumer¡¦s interests are arisen from the advertisement combination of the advertising creativity and the advertising appeal. Through advertising creativity level, different advertisement combinations of perceptual appeal and rational appeal show their effects. To understand different interest degrees that the consumers have toward the product. This research uses experimentation and profound interview, to discuss how interest effect that the advertisement combination of the advertising creativity and the advertising appeal has on the consumers. In order to understand how these four variables affect the consumers in product results the varying degree of interests, the partial experimentation was designed to 12 groups of hypothesized board advertisements, through out prior consumers 4 groups of hypothesized board advertisements combinations were selected, carries on the official experimentation. There are 111 questionnaires returned, 99 are valid, effective returns-ratio is 89%. The material analysis adopts one way ANOVA analysis, finally conclude: 1.There are obviously differences toward trust attitude between four groups of different advertisements combinations. 2.There are obviously differences toward preference between four groups of different advertisements combinations. 3.The advertisement combination "High creativity - perception" effectively increase the consumer's interests surpasses "the low creativity-perception" the advertisement combination, "the high creativity-rationality" advertisement combination and "low creativity-rationality" advertisement combination.
583

Dynamics Of Knowledge Production And The Social Formation Of The University

Ceyhan, Murat 01 September 2010 (has links) (PDF)
The purpose of this thesis is to establish a preliminary foundation of a research method aimed at understanding the social identity, role and function of the university. In this respect, it aims at identifying and articulating a set of issues, concepts, questions, social dynamics and so on, which have to be addressed and investigated carefully, before starting to build such a research method. To this end, the thesis focuses on and analyzes a recent debate on the changing nature of the contemporary social system of knowledge production / a debate constituted by several theses of change, namely, Mode 2, Finalization in Science, Post-normal Science, Academic Capitalism and Triple Helix, and the critiques directed towards these theses. In consequence, the thesis argues that to understand the social nature and function of the university, first and foremost, a versatile conceptual framework is required to capture the phenomenon of the social construction of the paradigm of knowledge/science / a phenomenon which is certainly nonlinear by nature and involves complex interrelations between scientific, political, economic and cultural realms.
584

A study on the Business Strategies of Multinational Mobil Communication Equipment Corporations in Mainland China

Shen, Chia-Hui 22 June 2000 (has links)
After China reform in 1979, telecommunication industry in Mainland China develops speedy, especially in mobile communication market. At present mobile telephone in Mainland China exceed 40 million. Mainland China is the third market in global mobile telephone market. The mobile communication equipment corporations that's worldwide to know, such as Motorola¡BNokia¡BEricsson etc. They have entry Mainland China to establish agencies in 1980s. Those corporations start a great quantity invest and set up sole venture or joint venture companies in 1990s. This study is to analyze mobile communication market in Mainland China and understands the mobile communication equipment corporations' business strategies. How they entry Mainland China and what is the factor influence they entry.
585

Investigation of Energy Coupling between Laser Diodes and Tapered Fibers, 2-D Case

Lee, Shun-Tien 30 June 2000 (has links)
Abstract Optical fiber communications have been become one of the most popular researches since 1970s. In this field, there are many studies on the coupling between semiconductor lasers and fibers and many conclusions are demonstrated. In this thesis we build a 2-D numerical model to simulate energy coupling between laser diodes (LDs) and tapered optical fibers. Our model is based on the spectral domain integral equation (SDIE) formulation which is derived from Maxwell equations and the principle of mode matching. Through this numerical model we will be able to show the field distribution in LD waveguide junctions. We may also use this tool to study the coupling parameters such as the separation distance and tapered fiber geometry.
586

The Relation between Laser Noise and Laser Longitudinal Modes in the Optical Disk System

Chiu, Pei-Yu 22 July 2000 (has links)
In optical disk systems, a semiconductor laser is used to read out the data recorded on the disc. Since the laser is the first noise source, there are strictly rated values for laser's noise in various optical disk systems to ensure the normal operation of the system. Among different laser noises, the worst one is the optical feedback noise. The feedback light will disturb the longitudinal modes of the laser and induce huge fluctuation in Laser's output. In our work, we study the effect of optical feedback on Laser's modes and relative intensity noises under various driving current and chop temperature. We try to find out methods that can suppress the Laser's noise and try to give some suggestions for the design of disc driven. Some experiments about a commercialized optical disk driver are also reported as well.
587

The Entry Strategy of Taiwanese Firm¡¦s Foreign Direct Investment in China

Tu, Cheng-Ching 20 June 2001 (has links)
In1987, the Government released the law about restricting people to cotact between Taiwan and China, and the trade between Taiwan and China became more and more important. With the trend of economic community in globe and the industrial environment in Taiwan changed, the Multinational Enterprises (MNEs) should think about them how to keep advantages in global competition. Internationalization is the best choice that can help Taiwanese enterprises promote their competitive position in the world. China is a developing market and a lot advantages, such as rich resources and cheaper labors. Above all, China has become the major location of Taiwanese firm¡¦s foreign direct investment. Compared with the process of MNEs located in North America/European Unit (developed countries, DC), the international process of Taiwan¡¦s MNEs is very different with in other countries. This is interested topic to investigate the entry strategies of Taiwanese firm¡¦s FDI in China. Focused on China, this thesis try to find out the model of entry mode and entry timing. The two basic types of entry mode are wholly owned subsidiary (WOS) and joint venture (JV). This study also defined the FDI timing of 1993 is the intermediary to differentiate early entrant from latter entrant. The study collects 48 effective cases from electronics and non-electronics industries. The analytical technique used in this research includes descriptive statistics, factor analysis, cluster analysis, bivariate correlations, Multivariate Analysis Covariate of Variance (MANCOVA) and logistic regression. The study finds that the strategic roles of the MNEs have significant influences on the choice of entry mode. With different strategic motivations, the type of entry mode and the timing of entry are also difference. The relationship between entry mode and entry timing is not significant. In the view of global logistic management, Taiwan¡¦s MNEs will be an early entrant in China.
588

Designing Portfolio Analysis System for E-Learning

Tsai, Min-Fang 06 August 2001 (has links)
In recent years, due to flourishing growth of internet, every protocol is approaching standardization and scientific applications are becoming full-grown everyday. Moreover, with the aid of internet educational resource and multimedia instruments, web-based instruction system has been enabled to build an internet learning environment which is different from traditional one. Teaching on the internet can not only overcome the limit of time and space, but also let students become more autonomous in their time and location of learning. Furthermore, all learning activities can be recorded in Web Logs automatically under the circumstances of not interfering with students when browsing learning material, interactive discussion, or team work learning. Because the Web Logs may also contain huge amount of non-educational meaning informations, teachers cannot directly use the Web Logs to observe student learning behaviors and to check learning situations. Many analytical instruments of Web Logs cannot either enable teachers to see educational meaning from Web Logs or carry out learning portfolio analysis. This research is to provide analysis of student Web Logs easily. Therefore, OLAP, and graphic data analytical techniques are used to design a visual learning portfolio analysis system. This system provides teachers to analyze the procedures of learning activities from different perspectives and graphic methods in order to understand the participatory extent of students toward learning activities. Besides, the evidence of students participate in learning activities will be surfaced, which can help teachers to evaluate the learning results effectively.
589

The Research on the Entry Mode and Operation Strategy for Taiwan Enterprises invest in Mainland China--Example of the Construction related Industry

Liu, Hui-Min 21 June 2002 (has links)
ABSTRACT Construction industry was used to be famous as the leader of whole industry, and had close relationship with prosperity, influenced the development of industry. However, the industry in Taiwan now is facing economic moves in circles and structure adjustment, and the key roles of the leading industry were replaced by high-tech industry. There were many documents about oversea entry mode and management abroad in Taiwan, but the records almost tended to manufacturing industry especially concentrating on the electronic industry, seldom discussed about construction industry. This study base on former experience and relevant theory in accordance with entry mode and operation strategy for construction industry which already to or desire to invest in Mainland China, and try to bring up some actually suggestion and manner, hopping that it can contribute to government for reference to draw up guidance and assistance policy. At the mean time, it is anticipated that this study could also assists the construction industry to make a right determination at business operation in Mainland. This study has found that even through the construction industry lied in difficult operation and low profits recently, the willing to Mainland China for invest is still weak. Most of them were changed their business to decoration, real estate, housing management and building materials industry .The main reason is people thought Mainland market still has some uncertain factors till now. According to this research, the restricted factors on laws & decrees and entry threshold are main influences for construction industry, which attends to invest in Mainland China. As above result it bring up many different kinds of register, such as borrowing a license form local company, registering by local people, acquiring local company, attaching to local company for cooperative business operation, registering as Taiwan merchant and registering as oversea company..etc. On the topic of operation strategy, traditional operation strategy for construction industry in Taiwan are overall cost leadship, economical scale, brand priority strategy, turnkey with funds raised by them, market segmentation. This study base on four strategies: market extension, market development, market penetration and diversification, which could further understanding the similarities and dissimilarities between theory and practice for construction industry. Investigating result shoes that the construction industry still place greater expectation in Mainland China, it is hope that they could use their superiority in company management & control, financial affairs control, marketing sale & development to coordinate various strategies such as diversification, brand priority strategy to develop new market, and in specialized field to get reasonable price .At the same time, they also wish themselves to be competed against in different market level, and choose a professional specialty to reach the goal . In general, this study has also found that the reasons for construction industry could not go all out to Mainland are the restriction on law & decrees in cross-Strait, high entry threshold relatively, difficult to shift business from one side to another, industry scale & capital insufficient, still raw in Mainland market, not have steady subcontractor, difficult to get business from the local government, lacking international view & globalization experience. It results that most of the construction industry now still can¡¦t make a decision to invest in Mainland China. The concrete suggestion of this study includes long-term & planned way to overall arrangement, carefully choose the right entry mode, localized in new business area, strategy alignment, seriously deal with account & tax, to be familiar with industry profession laws & decrees, specialization & diversification, operation management & cost control, train up globalization specialized field ability, to seize the opportunity of joining the WTO & applying for the Olympics, and other particular considerations such as region , traffic , climate ..etc. Restricted by the incompletely open up cross-Strait policy, the construction industry couldn¡¦t go all out to Mainland as manufacturing industry. Even through it was noticed during sample designing stage; the result of this study is difficult to get a universal experience in order to further analyze the entry mode of the construction industry. This study also uses case study to enhance the contents, but the number of sample and its representative is still insufficient. Herein, the successor could rely on more experience of construction industry and this topic to carry on further research in future.
590

Comparative Study: Time-Delay Method and Sliding Mode Technique for Perturbation Estimation

Huang, Jenn-Ming 15 July 2002 (has links)
Two different perturbation estimation methodologies are compared in this thesis. One is time delay method (TDM), the other is sliding mode techniqueli (SMT). When analyzing the TDM, Pade approximation is used to approximate a function with time-delay argument. The comparisons of perturbation estimation accuracy resulted from TDM and SMT both in time domain and frequency domain are addressed, and two numerical examples are also given for demonstration.

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