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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.
641

The Influence of Corporate Real Estate Ownership on the Risk and Return of Stockholders

Chung, Po-Hsiang 15 July 2012 (has links)
There are many reasons for companies to hold real estate, including for operating business, production, sales, and providing services. Previous researches show that corporate real estate (CRE) is an important part of company assets, and it will affect stock returns and risk of company. The main object of this study is to investigate the impact of changes in CRE on stock returns and risk of company in Taiwan. Moreover, this study analyzes how CRE affect toward different industry during each business cycle period. Then, we provide some suggestions to stockholders and managers. The data set from 1992 through 2011 in Taiwan stock market, the relationship between CRE and stock returns and risk are analyzed using two stage least squares regression model. The empirical results show that, on average, higher CRE appears to be associated with higher abnormal return performance and higher total risk. On the other hand, CRE show negative impact on business operation such as lower adjusted return on assets and higher risk of bankruptcy. Furthermore, CRE factor is associated with higher abnormal return performance and higher firm value when company with small asset size, high P/E ratio or newly establish characters. Results also indicate that the impact of CRE on firm¡¦s stock price and risk depend on industries, business cycle period, and firm characters. CRE show negative impact on Textile, Tourism, and Trading and Consumers' Goods Industry. In Food Industry, higher CRE factor is associated with lower system risk and positive impact on business operation.
642

Blind Adaptive Multiuser Detection for DS-CDMA System Based on Sliding Window RLS Algorithm

Pan, Wei-Hung 10 September 2004 (has links)
Direct sequence code division multiple access (DS-CDMA) technique is one of the significant multiplexing technologies used in wireless communication services. In the DS-CDMA framework, all users have been assigned distinct signature code sequence to achieve multiple accesses within the same frequency band, and allow signal separating at the receiver. Under multipath fading environment with near-far effect, the current CDMA systems employed the RAKE receiver, to enhance the system performance. It is known that if training data is available the minimum mean squares error (MMSE) multiuser receiver, in which the average power of the receiver output is minimized subject to appropriate constraints, could be obtained by solving directly by the constrained Wiener estimation solution. However, if this is not the case, the blind multiuser receiver is an alternative approach to achieve desired performance closed to the one with the MMSE approach. In this thesis, based on the max/min criterion, the blind multiuser receiver, with linear constraints, is devised. Here constraint equations are written in parametric forms, which depend on the multipath structure of the signal of interest. Constraint parameters are jointly optimized with the parameters of the linear receiver to obtain the optimal parameters. In consequence, the sliding window linearly constrained RLS (SW-LC-RLS) algorithm is employed to implement the optimal blind receiver, with max/min approach. This new proposed scheme can be used to deal with multiple access interference (MAI) suppression for the environments, in which the narrow band interference (NBI) due to other systems is joined suddenly to the DS-CDMA systems, and having serious near-far effect. Under such circumstance, the channel character due to the NBI and near-far effect will become violent time varying, such that the conventional LC-RLS algorithm as well as LC-LMS algorithms could not perform well. Via computer simulation it confirms that our proposed scheme has better capability for MAI suppression in DS-CDMA systems than other existing schemes, and is more robust against the NBI and near-far problems.
643

An Improved C-Fuzzy Decision Tree and its Application to Vector Quantization

Chiu, Hsin-Wei 27 July 2006 (has links)
In the last one hundred years, the mankind has invented a lot of convenient tools for pursuing beautiful and comfortable living environment. Computer is one of the most important inventions, and its operation ability is incomparable with the mankind. Because computer can deal with a large amount of data fast and accurately, people use this advantage to imitate human thinking. Artificial intelligence is developed extensively. Methods, such as all kinds of neural networks, data mining, fuzzy logic, etc., apply to each side fields (ex: fingerprint distinguishing, image compressing, antennal designing, etc.). We will probe into to prediction technology according to the decision tree and fuzzy clustering. The fuzzy decision tree proposed the classification method by using fuzzy clustering method, and then construct out the decision tree to predict for data. However, in the distance function, the impact of the target space was proportional inversely. This situation could make problems in some dataset. Besides, the output model of each leaf node represented by a constant restricts the representation capability about the data distribution in the node. We propose a more reasonable definition of the distance function by considering both input and target differences with weighting factor. We also extend the output model of each leaf node to a local linear model and estimate the model parameters with a recursive SVD-based least squares estimator. Experimental results have shown that our improved version produces higher recognition rates and smaller mean square errors for classification and regression problems, respectively.
644

Numerical Methods for Wilcoxon Fractal Image Compression

Jau, Pei-Hung 28 June 2007 (has links)
In the thesis, the Wilcoxon approach to linear regression problems is combined with the fractal image compression to form a novel Wilcoxon fractal image compression. When the original image is corrupted by noise, we argue that the fractal image compression scheme should be insensitive to those outliers present in the corrupted image. This leads to the new concept of robust fractal image compression. The proposed Wilcoxon fractal image compression is the first attempt toward the design of robust fractal image compression. Four different numerical methods, i.e., steepest decent, line minimization based on quadratic interpolation, line minimization based on cubic interpolation, and least absolute deviation, will be proposed to solve the associated linear Wilcoxon regression problem. From the simulation results, it will be seen that, compared with the traditional fractal image compression, Wilcoxon fractal image compression has very good robustness against outliers caused by salt-and-pepper noise. However, it does not show great improvement of the robustness against outliers caused by Gaussian noise.
645

Modelling And Predicting Binding Affinity Of Pcp-like Compounds Using Machine Learning Methods

Erdas, Ozlem 01 September 2007 (has links) (PDF)
Machine learning methods have been promising tools in science and engineering fields. The use of these methods in chemistry and drug design has advanced after 1990s. In this study, molecular electrostatic potential (MEP) surfaces of PCP-like compounds are modelled and visualized in order to extract features which will be used in predicting binding affinity. In modelling, Cartesian coordinates of MEP surface points are mapped onto a spherical self-organizing map. Resulting maps are visualized by using values of electrostatic potential. These values also provide features for prediction system. Support vector machines and partial least squares method are used for predicting binding affinity of compounds, and results are compared.
646

Non-normal Bivariate Distributions: Estimation And Hypothesis Testing

Qumsiyeh, Sahar Botros 01 November 2007 (has links) (PDF)
When using data for estimating the parameters in a bivariate distribution, the tradition is to assume that data comes from a bivariate normal distribution. If the distribution is not bivariate normal, which often is the case, the maximum likelihood (ML) estimators are intractable and the least square (LS) estimators are inefficient. Here, we consider two independent sets of bivariate data which come from non-normal populations. We consider two distinctive distributions: the marginal and the conditional distributions are both Generalized Logistic, and the marginal and conditional distributions both belong to the Student&rsquo / s t family. We use the method of modified maximum likelihood (MML) to find estimators of various parameters in each distribution. We perform a simulation study to show that our estimators are more efficient and robust than the LS estimators even for small sample sizes. We develop hypothesis testing procedures using the LS and the MML estimators. We show that the latter are more powerful and robust. Moreover, we give a comparison of our tests with another well known robust test due to Tiku and Singh (1982) and show that our test is more powerful. The latter is based on censored normal samples and is quite prominent (Lehmann, 1986). We also use our MML estimators to find a more efficient estimator of Mahalanobis distance. We give real life examples.
647

Analysis Of Critical Factors Affecting Customer Satisfaction In Modular Kitchen Sector

Ozer, Semih 01 May 2009 (has links) (PDF)
This study starts with the review of the literature in customer satisfaction, customer satisfaction methods and models. After selecting a proper customer satisfaction method and model, the study conducts a survey and a questionnaire among the customers and professionals in the modular kitchen sector. The aim of the study is to analyze the factors affecting customer satisfaction and finding out the ones related with the modular kitchen sector. After applying the survey, the relations between the inputs and outputs of the satisfaction are analyzed with the overall satisfaction itself. The strong and weak factors are determined and a proper CRM tool is build-up to realize a decision-support and forecast tool in the study, which can be seen as a beginning for the companies in the real sector in this business to build a much more detailed and ERP integrated software and to use them. The results of the survey are compared with the similar studies from the literature.
648

E-government Adoption Model Based On Theory Of Planned Behavior: Empirical Investigation

Kanat, Irfan Emrah 01 July 2009 (has links) (PDF)
The e-government phenomena has become more important with the ever increasing number of implementations world wide. A model explaining the e-government adoption and the related measurement instrument a survey had been developed and validated in this study. In a post technology acceptance model (TAM) approach, theory of planned behavior (TPB) was extended to t the requirements of e-government context. The adoption of student loans service of the higher education student loans and accommodation association (KYK) was investigated to obtain data for empirical validation. The instrument was administered to over four-hundred students and partial least squares path modeling was employed to analyze the data. The results indicate that the model was an improvement over TAM in terms of predictive power. The constructs investigated in the study successfully explained the intention to use an e-government service.
649

Development Of A Multi-dimensional Model To Evaluate Higher Education Instructors

Findik, Duygu 01 July 2010 (has links) (PDF)
Through the rapid expansion of information technologies, Learning Management Systems have become one of the most important innovations for delivery of education. Successful implementation and management of these systems are primarily based on the instructors&#039 / adoption. However, too few researches have been conducted to evaluate instructors&rsquo / adoption towards e-learning system as taking higher education as base. This study aims to understand behavioral intentions of higher education instructors towards Learning Management Systems and further to identify the influencing factors. A research model has been proposed based on the belief variables of the Technology Acceptance Model. Additionally, Application Characteristics, Individual, Social and Technological dimensions were considered to identify the effects of key variables on behavioral intention of users. A survey instrument has been developed and conducted with 224 academicians after a pilot study through its reliability and validity has been assured. Although the items of the survey instrument were based on the literature, an explanatory factor analysis was performed to strictly determine which items belong to which factors. Then, in order to assess the measurement model Convergent validity and Discriminant validity were conducted via confirmatory factor analyses. After the required prior analyses, Component based Structural Equation Modeling (Partial Least Square - PLS) was used to validate the predictive power of the proposed research model. Consequently, relationships between the influencing factors were detected and the results showed that the factors related with Belief dimension directly influenced behavioral intention of instructors. Also, the factors under the Individual, Social and Technological dimensions indirectly affected behavioral intention of users towards learning management system use. Additionally, structured and informal interviews were performed with ten instructors and the findings of the research model were explained with the opinions of system users. The indications of this research will be valuable for implementation, management and continuous improvement of learning management systems.
650

Estimation of Orthogonal Regression Under Censored Data.

Ho, Chun-shian 19 July 2008 (has links)
The method of least squares has been used in general for regression analysis. It is usually assumed that the errors are confined to the dependent variable, but in many cases both dependent and independent variables are typically measured with some stochastic errors. The statistical method of orthogonal regression has been used when both variables under investigation are subject to stochastic errors. Furthermore, the measurements sometimes may not be exact but have been censored. In this situation doing orthogonal regression with censored data directly between the two variables, it may yield an incorrect estimates of the relationship. In this work we discuss the estimation of orthogonal regression under censored data in one variable and then provide a method of estimation and two criteria on when the method is applicable. When the observations satisfy the criteria provided here, there will not be very large differences between the estimated orthogonal regression line and the theoretical orthogonal regression line.

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