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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.
511

Factors Affecting the Adoption of Mobile Technology ¡Xthe Fit-Viability Perspective

Huang, Hsiao-chun 21 January 2007 (has links)
The increased popularity in mobile devices and technology has motivated business to adopt the technology for increased productivity. However, not much research has investigated the adoption of mobile technology. The purpose of this thesis is to study the factors that influence the adoption of mobile technology and to develop a model of mobile technology adoption. The model can serve as a foundation for future research and provide useful guidelines for organizations that plan to adopting mobile technology. The model suggests two categories of factors that determine the decision of adopting mobile technology: fit and viability. Fit measures whether the functional capabilities of mobile technology match the need of a task, whereas viability measures whether an organization is ready for the technology. This research develops instruments for measuring fit and viability. A survey was conducted to collect data for model evaluation. Major findings from the study include: (1) the fitness between task and technology had a direct positive impact on the success of mobile system adoption. (2) Personal characteristic and organizational viability had indirect positive impacts on the success of mobile system adoption via the mediation of system quality. (3) Personal characteristic and organizational viability had positive impacts on the information quality and system quality but had no impact to the service quality. (4) Only the system quality had a positive impact on the success of mobile system adoption.
512

Modeling Software with UML¡ÐA Case Study of Personnel Leave System

Chang, Jei-Chen 23 July 2007 (has links)
Modeling software with the model driven architecture (MDA) concept and unified modeling language (UML) has become a new trend for the objected-oriented systems analysis and design. Several CASE tools which embed MDA concept and UML have been introduced to facilitate the transformation from platform independent model (PIM, i.e., class diagram) to platform specific model (PSM) in order to enhance the efficiency of software development. In this work, we present a systematic methodology which integrates the concept of MDA and UML with CASE tool to refine the process of UML transformation. A personnel leave prototype system is implemented to illustrate the concepts, application, and advantages of the proposed methodology. With this approach, software developers can construct the PIM efficiently and thereby enhance the efficiency of system development.
513

The impact on banks' portfolio under BIS amendment to the capital accord of 1996 and reserve requirement

Chiu, Yu-Fen 23 June 2000 (has links)
The impact on banks' portfolio under BIS amendment to the capital accord of 1996 and reserve requirement.
514

Image Modeling Appropriate for Kalman Filtering

Tai, Kuo-Wei 28 July 2000 (has links)
In stochastic representation an image is a sample function of an array of random variables which is called a random field. For characterizing an ensemble of images, we choose an autoregressive model as our image model. An image model often applies to image processing such as image data compression and image restoration. Therefore the validity of the image model affect it¡¦s performance of image processing. The output of the AR model depends on its parameters ¡V system transition matrix and generating noise. Hence the validity of this model is related to these two parameters. How to seek the standard of the validity of the image model is a problem. We exploit performance of image model¡¦s application ¡V image restoration - to find a method of determining the validity of the image model. In our paper we find a relation between image restoration performance and image model¡¦s parameters by the Kalman filtering equations. An image model with lower generating noise power and system transition matrix is better for image restoration and is considered a good image model. In the analysis of the parameters of the image model, we can meet the requirements of the parameters by image segmentation method, residual image method and normalized image method. In addition it also helps us understand the Kalman filter much more and know how to find the solution of similar problems.
515

Development of Matching System in the Electronic Marketplace

Cheng, Fu-Chien 11 July 2001 (has links)
Abstract¡G With the rapid development of electronic marketplace, buyers and sellers can trade more easily without the limitations of time and distance. Internet trading is benefited to both sides in many ways. However, the matching mechanism between buyers and sellers in the electronic marketplace is not explored deeply. Consequently, the purpose of this research is to study the screening and negotiation in the process of matching. In this research, four screening models and related flow charts have been proposed. A negotiation model is also proposed to deal with the bargaining process. Finally, a prototype based on development method is built to demonstrate how the screening models and negotiation models work.
516

Effect of soften on colossal manganites

Lu, Wei-Chun 31 July 2002 (has links)
Abstract The softening effects of ferromagnetic magnon on some ferromagnetic semiconductors and colossal magnetoresistance manganites have attracted much attention. Such effect can be calculated from the single orbital ferromagnetic Kondo lattice model in proper conducting carrier numbers utilizing the equation of motion method with one magnon excitation and Random Phase approximations. However, if we take into account the Coulomb repulsion and use the Gutzwiller projection method to transfer this repulsion force to conducting bandwidth modulation, the softening effect disappear. This paper describes qualitively the effect of softening on properties of different colossal manganites.
517

Numerical Study of the Primary Production in the Tapeng Bay

Chen, Chun-Nan 22 August 2002 (has links)
A 3D numerical model ¡V COHERENS has been applied to construct a coupled hydrodynamic and ecological model for studying Tapeng Bay, which is a coastal lagoon situated in southwest of Taiwan. The simulations have been carried out to study the influences and their interacting mechanisms among the tidal currents, nutrients and micro planktons in the Lagoon. Model results have been compiled for calculating the nutrient fluxes and the primary productions in the Tapeng Bay. Tapeng Bay is a semi-enclosed coastal lagoon, which has only one tidal inlet for exchanging lagoon water with the coastal currents along the Kaoping coast on the narrow shelf in southwest of Taiwan. The study area is situated in the tropical climate zone where has sunshine through out the year except the rainy days concentrated in the summer season, which is influenced by the southwest monsoon. There are several drainage channels that collect the untreated domestic sewerage and wastewater discharged from the fish farms surround the lagoon. The discharges in these channels are usually low during the dry season. The solid contained in the water are mostly settled on the channel beds. During the raining season, high discharges due to the storm rainfalls re-suspend the sediments and carry into the lagoon. These sediments, which contain high concentrations of suspended solids and nutrients, cause the Bay water highly eutrophied. Therefore, the Bay is fully influenced by the seasonal variations. There are a lot of aquaculture, i.e. oyster farming and fish cage, in the Bay area since the water is calm and rich. But the balance between the nature and the anthropogenic disturbance is breaking. Besides the water level variation generated from the tidal inlet, the fresh water inflow from 3 major channels are included in the model to simulate their influences to the hydrodynamics and the density driven circulation due to changing salinities and temperatures from these inlets. Plankton, detritus, dissolved nutrients and dissolved oxygen is taking into account as the model variables for this marine eco-system. The plankton growth is mainly generated due to temperature, light intensity and nutrient level. Only the nitrogen cycle has been considered in the model by assuming there are enough supply of phosphate and silicate. Model runs have been carried out according to different seasonal situations of the boundary conditions. Furthermore, climates (heats, lights, winds, etc) are also included in the model to distinct seasonal characteristics. It is shown, from the model results, that the currents mainly dominate the distribution of nutrients in the Tapeng Bay. The nutrient level controls plankton growth. The nutrient sources are mainly coming from the coastal currents (through tidal inlet) in the wintertime, whereas the summer source was from the drainage channels due to the wash out by the high discharge rates. Beside these, dissolved oxygen concentrations in the Bay water are strongly influenced by the plankton growth rate, faster the photosynthesis higher the DO concentrations. The eutrophication levels of the Tapeng Bay water have been compiled using the plankton carbon level modeled at various situations. According to the Nixon standard (1995), Tapeng Bay has eutrophication through out the year. Mesotrophic condition can be observed during the wintertime, whereas the hypereutrophic level can be concluded during the raining season.
518

Constructing Hydrodynamic and Water Quality Models in a Tidal River Using System Dynamics Simulation Tools

Chen, Han-Hsin 11 September 2002 (has links)
Abstract The main purpose of this study is to develop a hydrodynamic and water quality model using the system dynamic software-STELLA for the tidal river simulations. The model consists of three modules: the hydrodynamic module simulates the water level variation and the dynamic flow conditions in tidal rivers; the transport module simulates the temporal and spatial variations of dissolved matters; and water quality module simulates the bio-chemical reaction processes and the fates of the water quality variables. Water quality module was established from the conceptions of WASP6 with some modifications. Eight state variables are included in the water quality module, i.e. chlorophyll-a, organic phosphorus, inorganic phosphorus, organic nitrogen, ammonia, nitrate, carbonaceous biochemical oxygen demand, and dissolved oxygen. Most the hydrodynamic and water quality models, either imported or domestic developed, were coded in FORTRAN or other conventional programming languages. In this study, the system dynamics software STELLA has been used to construct the model. The study has overcome the difficulty of using STELLA to simulate space continuity and unsteady state condition of tidal river systems. By using STELLA, the environment model can easily be integrated with researches in social-economical studies. The theories and the developments of the model are described in the thesis, the calibration and verification processes of the model using observation data of the Tamshui River system are also describe in detail. The model can be used not only to simulate and to predict the tidal flow, salinity, temperature, and water quality conditions in the Tamshui River, but also be used to evaluate the effects of various water quality purification methods and strategies. Therefore, this model can also assist policymakers to make better decisions on the balancing the economic developments with environmental protections.
519

The Study of Phase Transition of The Torsion X-Y Model

Huang, Wen-Kuei 27 January 2003 (has links)
The phase transitions of a newly proposed torsion X-Y model, are studied with molecular dynamics. ForJ3 >0, the influence from J1 term is similar to the term.We found the Torsion X-Y Model and X-Y Model or Coupled X-Y Model all have the Kosterlitz-Thouless transition. (KT) We also confirm that the KT transition is a second order transition , The distribution of angle £c start from dis-ordered to well-ordered. KT starts first before the randomly distributed £c shows preference and ends when the preference is merged. For the J3 <0 case, the KT is also found in J3=-0.0167 and J3=-0.0334 The temperature for negative J3 is lower then that for positive J3 due to the resistant force to £c ordering from the coupled interaction.
520

Performance of Financial Holding Company from Finance Factor

Chen, Chia-Yi 27 May 2003 (has links)
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