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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.
211

The study of the relationship among hospital employees, emotion labor load and customer-oriented behavior

Tai, Hsiu-Ching 27 August 2003 (has links)
The Abstract of Thesis Title¡GThe study of the relationship among hospital employees, emotion labor load and customer-oriented behavior. School¡GNational SUN YAT-SEN University Department¡GInstitute of Human Resource Management Academic year¡G91 Author¡GHsiu-Ching Tai Adviser¡GDr. Bih-Shiaw Jaw Dr. Liang-Chih Huang Abstract At the world competition period, business must pay more attention to customer oriented service and customer satisfaction as the company core ability to face the challenges. Customer-oriented behavior is the necessary condition for business to exist in the world and it becomes the business management trend. Medical treatment in Taiwan will make a revolution in the 21st century by the medical policy changes. This situation makes the hospital management become harder and face more challenges. Medical service industry doesn¡¦t only have normal trait like the common service industry, but also have many specific traits. However, the hospital is a working environment with high emotional labor load. If hospital employees can not deal with their emotions appropriately, it will cause emotional exhaustion and influences customer-oriented behaviors. In order to understand if the emotional exhaustion is a mediator between the emotional labor load and the customer-oriented behavior, also, if the emotional management affects the emotion labor load, emotion exhaustion and customer-oriented behavior is the research purpose. The samples are 503 employees of two hospitals at Kaohsiung, but the valid questionnaires are 399. After SPSS for Windows 8.0 statistic analyzing, the results are summarized as following: 1. The hospital employees with different characters will lead to variance emotional labor load, emotional exhaustion, emotional management and customer-oriented behaviors. 2. There is a relationship between the emotional labor load, emotional exhaustion and customer-oriented behaviors. 3. The relationship between the emotional labor load and customer-oriented behavior has prediction. 4. The emotional exhaustion has intermediary effect between emotional labor load and customer-oriented behavior. 5. The emotional management of emotional empathy, emotional expression and awareness have mediator effects between the emotional labor load and emotional exhaustion. Therefore, the high emotional labor load of hospital employees can be eliminated by emotional expression and awareness, and the emotional exhaustion can be decreased. Then, this situation will influence the customer-oriented behavior. Also, management use human resource management proposal to reinforce employees¡¦ emotional manage skills. IT will help employees decrease the emotional labor load, emotional exhaustion, and improve customer-oriented behavior. Key Words: hospital employees, emotional labor load, emotional exhaustion, emotional management, customer-oriented behavior.
212

Design and Analysis of a Highly Efficient File Server Group

Liu, Feng-jung 29 January 2005 (has links)
The IT community has increasingly come to view storage as a resource that should be shared among computer systems and managed independently of the computer systems that it serves. And, the explosive growth of the Web contents has led to increasing attention on two major challenges: scalability and high availability of network file system. Therefore, the ways to improve the reliability and availability of system, to achieve the expected reduction in operational expenses and to reduce the operations of system management of system have become essential issues. A basic technique for improving reliability of a file system is to mask the effects of failures through replication. Consistency control protocols are implemented to ensure the consistency among these replicas. In this dissertation, we leveraged the concept of intermediate file handle to cover the heterogeneity of file system. But, the monolithic server system suffered from the poor system utilization due to the lack of dependence checking between writes and management of out-of-ordered requests. Hence, in this dissertation, we followed the concept of intermediate file handle and proposed an efficient data consistency control scheme, which attempts to eliminate unnecessary waits for independent NFS writes to improve the efficiency of file server group. In addition, we also proposed a simple load-sharing mechanism for NFS client to improve system throughput and the utilization of duplicates. Finally, the results of experiments proved the efficiency of the proposed consistency control mechanism and load-sharing policy. Above all, easy to implement is our main design consideration.
213

Development of a Weight Control System for Ship Construction

Tsao, Jui-lin 24 June 2005 (has links)
It is a vitally important task to achieve control of the weight and center of gravity of lightship during building a new ship. If the lightship weight is slightly out of control, the deadweight inadequacy and a deviation from the initial design target will be caused. The basic performance and function of a ship at sea are also resulted. Furthermore, if the lightship weight is incompletely under control, it will bring about an unsafe vessel, ship-delivery difficulty and a severe loss for shipbuilder. Docking arrangement is optimized to allocate by using the state-of-the-art finite element method to analyze the lightweight distribution as the load and the ship girder as a beam; in addition, the dock is recognized as a spring-liked elastic foundation subjected to compression only. It is verified by comparison between measurement of the lightship weight by means of the weight control system on land and the traditional inclining experiment. Based on the results, it can be shown that the whole system is reliable, available and efficient. The load cell is utilized as a component of the weight control system to measure the compressive force (i.e., ship weight) at a specified dock. The main function of the system is to determine the lightweight and its C.G. on-land construction instead of the time-consuming and labor-wasting traditional way. The presented methodology will be beneficial for weight control of a new-ship building in the future.
214

Application of ARIMA and ANN for Load Forecasting of Distribution Systems

Ku, Te-Tien 05 July 2006 (has links)
The objective of this thesis is to study the load forecasting of distribution feeders and substations for Fong-Shan District of Taiwan Power Company. To increase the accuracy of load forecasting, the load characterization of customers served has been investigated. The typical load patterns of different customers classes and derived by performing the statistic of power consumption data retrieved. The daily load profiles and load consumptions data distribution feeders and substations have been solved by considering the typical load patterns and energy consumption of all customers served. To investigate the correlation ship of temperature and energy consumption of customer classes, the temperature sensitivity of customer energy consumption has been used to update the load composition and the contribution of load change by different customer classes. To perform the load forecasting of distribution systems, the linear, nonlinear and hybrid load forecasting modules have been proposed. The historical load data of distribution feeders and substations in Fong-Shan District have been used to derive the load forecasting modules. To analyze the accuracy of load forecasting by considering the temperature effect, the temperature change is included in the load forecasting module. With the load forecasting derived, the proper load transfers among different distribution feeders and different substations have been determined to achieve the load balancing of service areas.
215

The Observation of Dislocation Morphologies in Asymmetric Strain of IF Steel

Wang, Tain-de 30 January 2007 (has links)
The low cycle fatigue test of IF steel was controlled at 0.6%, 0.4%, 0.2%, and 0.1% strain amplitude until the specimens cracking. After 10000 cycles at 0.4% strain amplitude, changed the strain amplitude from 0.4% to 0.2%. We chose the steps of the low cycle fatigue test under reducing amplitude at 1000, 10000, and 20000 cycles. In addition, after 10000 cycles at 0.6% strain amplitude, changed the strain amplitude from 0.6% to 0.2%. We chose the steps of the low cycle fatigue test under reducing amplitude at 3000, 20000 and 100000 cycles. Then we used electron microscope to observe the dislocation structure, and knew the dislocation morphology of evolution process under reducing amplitude. The dislocation structure evolution of IF steel at low strain amplitude (0.1%, 0.2%) during low cycle fatigue developed the loop patches, dislocation walls, and dislocation cells step-by-step by increasing fatigue cycles. However, the dislocation structure evolution would be changed in the low cycle fatigue under reducing amplitude. We could observe that the dislocation cells were broken to the loop patches in different form. Attest to the dislocation morphology was changed under reducing amplitude. After 10000 cycles at 0.4% strain amplitude, change the strain amplitude from 0.4% to 0.2%., we could observe that the dislocation cells were broken to the loop patches and vein structure. And after 100000 cycles under changed loading amplitude from 0.6% to 0.2%, large area of open domains and some loop patches can be observed.
216

A Traffic-Load Oriented Power Saving Mechanism in Ad Hoc Networks

Tan, Jui-hua 13 February 2007 (has links)
The mobile ad hoc network (MANET) has become a popular technology in recent years. Due to most devices are battery powered, energy conservation is a critical issue in the MANET. To save energy and extend battery life, nodes should turn their radios off when they have no packet to send or receive. To achieve this, IEEE 802.11 defined a synchronous power saving mechanism (PSM) based on periodical beacon transmission. It allows devices to turn their radios off when no data has to be sent or received. However, the idle state is long because the device must remain awake during the entire beacon interval even though there is only a small amount of data packets to be sent. Although some PSMs have been proposed, they still suffer from a long idle state. In this paper, we propose a new power saving mechanism by dynamically adjusting the sleeping time based on the network traffic. Simulation results show that the proposed PSM outperforms other PSMs in energy goodput and lifetime.
217

An Implementation of Digital Power Meter

Lai, Ray-Chung 14 June 2000 (has links)
Power measurement is important for various purposes such as revenue metering, power quality improvement, and direct load control. Various algorithms for power measurement have been proposed in the time domain, which implies a simple instrumentation, but more useful power formulations have been derived in the frequency-domain approach which would require appropriate sampling and measurement techniques to avoid long delay in processing voltage and current signals. The aim of this thesis to implement a measurement instrument that can measure the power components digitally and efficiently under sinusoidal and non-sinusoidal situations. We will use a high performance digital signal processing (DSP) chip and adopt a frequency domain based algorithm for the computation of power elements. The measurement system is expected to offer both high speed and accuracy, and can show wide spectra limited only by the sampling frequency.
218

A Skeleton Supporting Group Collaboration, Load Distribution, and Fault Tolerance for Internet-based Computing

Chiang, Chuanwen 13 August 2001 (has links)
This dissertation is intended to explore the design of a dual connection skeleton (DCS), which facilitates effective and efficient exploitation of Internet-centric collaborative workgroup and high performance metacomputing applications. The predominant difference between DCS and conventional frameworks is that DCS administers a network of brokers that are grouped into a logical ring. New mechanisms for group collaboration, load distribution, and fault tolerance, which are three crucial issues in Internet-based computing, are proposed and integrated into the dual connection skeleton. Collaborative workgroup becomes a significant common issue when we attempt to develop wide area applications supporting computer-supported cooperative work (CSCW). For group collaboration, DCS therefore offers a strategy for concurrency control that ensures the consistency of shared resources. By using the strategy, multiple users in a collaborative group are able to simultaneously access shared data without violating its consistency. With respect to load distribution, additionally, DCS applies an adaptive highest response ratio next (AHRRN) algorithm to job scheduling. Performance evaluations on competing algorithms, such as shortest job first (SJF), highest response ratio next (HRRN), and first come, first served (FCFS) are conducted. Simulation results demonstrate that AHRRN is not only an efficient algorithm, but also is able to prevent the well-known job starvation problem. In a parallel computational application, one can further decompose a composite job into constituent tasks such that these tasks can be assigned to different PEs for concurrent execution. The dual connection skeleton thus makes use of a proposed dynamic grouping scheduling (DGS), to undertake task scheduling for performance improvement. The DGS algorithm employs a task grouping strategy to determine computational costs of tasks. It re-prioritizes unscheduled tasks at each scheduling step to explore an appropriate task allocation decision. In terms of the schedule length, the performance of DGS has been evaluated by comparing with some existing algorithms, such as Heavy Node First (HNF), Critical Path Method (CPM), Weight Length (WL), Dynamic Level Scheduling (DLS), and Dynamic Priority Scheduling (DPS). Simulation results show that DGS outperforms these competing algorithms. Moreover, as for fault tolerance, DCS utilizes a dual connection mechanism for computational reliability enhancement. For the sake of constructing dual connection, we examine five approaches: RANDOM, NEXT, ROTARY, MINNUM, and WEIGHT. Each one of these approaches can be incorporated into DCS-based wide-area metacomputing systems. Performance simulation shows that WEIGHT benefits the dual connection the most. A DCS-based scientific computational application named the motion correction is used to demonstrate the fault tolerant ability of DCS. Putting the group collaboration, load distribution, and fault tolerance issues together, the dual connection skeleton forms a seamless and integrated framework for Internet-centric computing.
219

The Temperature Sensitivity Analysis of Power System Load Demand with Neural Networks

Chen, Chih-Hung 20 June 2002 (has links)
The Temperature Sensitivity Analysis of Power System Load Demand with Neural Networks Chih-Hung Chen* Chao-Shun Chen** Institute of Electrical Engineering National Sun Yat-Sen University Kaohsiung, Taiwan, R.O.C. ABSTRACT The analysis of customer load characteristic plays the fundamental role of power system operation. Based on the load survey study, the load pattern of each customer class is derived to achieve more effective load forecast for system planning to reduce the risk of system capacity shortage. For the load survey study, a stratified sampling method has been used to select the proper size of customers for meter installation to collect the customer power consumption. By the way, the customer load patterns derived can represent the load behavior of whole customer population. The standardized daily load pattern of each customer class has been solved with the mean per-unit method of customer load. According to the total power consumption by all customers within the same class and considering the corresponding daily load pattern, the daily load profile of the customer class is then determined. The standard daily load pattern of each customer class and total power consumption within the territory of service districts of Taipower system are integrated to construct Taipower system daily load profile. The temperature sensitivity analysis of customer power consumption is performed for each customer class by applying neural networks. The proposed method has been used to investigate the change of power consumption due to temperature rise for each district and Taipower system. For the districts with high ratio of the air conditioner loading, the increase of power consumption is in proportion to the temperature. It is concluded that the research of temperature sensitivity on power consumption can support power system operation and better capacity planning of power system in the future. *Author **Advisor
220

Power System Planning and Harmonic Mitigation of Mass Rapid Transit Systems

Chuang, Hui-Jen 27 June 2002 (has links)
This dissertation is to investigate the power system service quality of a Mass Rapid Transit (MRT) system and derive the proper transformer planning to enhance the system operation efficiency. The transformer loading factor is improved by proper capacity planning by considering the power demand according to the growth of ridership. To mitigate the harmonic distortion, the installation location and capacity of harmonic filters are designed and verified by computer simulation. In this dissertation, the software programs for the AC/DC load flow study and harmonic analysis have been developed and integrated to simulate the MRT power system. To enhance the accuracy of computer simulation for the system operation with multiple trains on the main lines, the effect of voltage fluctuation to the traction effort of a train set is considered in the AC/DC load flow analysis. The mathematical model of 12-pulse uncontrolled rectifiers without interphase transformers has been derived and implemented in the programs to obtain more accurate simulation results. To achieve better cost effective capacity planning of main transformers, the unit commitment is applied to derive the optimal transformer capacity to meet the annual peak demand and provide reserve for service reliability. The power consumption of an MRT system is varied with the train operation modes and the route gradient, curvature of MRT networks. The motion equation of train sets has been applied to find the dynamic power consumption and travel distance for each time snapshot. The AC/DC load flow analysis is performed to find the annual power loading of traction substations and whole Taipei MRT network. The energy loss, investment cost of main transformers, and the system service reliability are used to define the equivalent cost of all feasible states for each dynamic programming stage. According to the computer simulation, significant cost saving has been obtained by the proposed methodology for transformer capacity planning of Taipei MRT network. Due to the dynamic load behavior of train sets, the stochastic harmonic distortion of an MRT system is simulated. The mathematical model of the 12-pulse uncontrolled rectifiers without interphase transformers is considered in the harmonic load flow analysis to solve the power demand and harmonic injection currents at traction substations for each time snapshot. According to the mean values and standard deviation of injection harmonic currents, the stochastic harmonic load flow analysis is executed to find the average value and the confidential interval of harmonic voltage distortion for all system buses. By this method, the system voltage harmonic distortion can be evaluated more accurately to provide better guidance for the strategy of harmonic mitigation. According to the results of the stochastic harmonic load flow, different strategies of harmonic distortion mitigation are investigated. Both the fixed type and switching type of passive filters are considered to be implemented. The cost function of filter investment and the harmonic distortion are used in the objective function by considering the regulation of harmonic distortion and system voltages as the constraints. By performing the nonlinear programming, the proper capacity of harmonic filters for each harmonic order and the corresponding switching time of unit commitment is determined. To further improve the power quality, the hybrid filter is also proposed for better distortion mitigation. The analysis of distortion mitigation by harmonic filters are performed to demonstrate the effectiveness of the hybrid filters to improve the power quality of MRT systems.

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