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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.
151

Design, set up, and testing of a matrix acidizing apparatus

Nevito Gomez, Javier 30 October 2006 (has links)
Well stimulation techniques are applied on a regular basis to enhance productivity and maximize recovery in oil and gas wells. Among these techniques, matrix acidizing is probably the most widely performed job because of its relative low cost, compared to hydraulic fracturing, and suitability to both generate extra production capacity and to restore original productivity in damaged wells. The acidizing process leads to increased economic reserves, improving the ultimate recovery in both sandstone and carbonate reservoirs. Matrix acidizing consists of injecting an acid solution into the formation, at a pressure below the fracture pressure to dissolve some of the minerals present in the rock with the primary objective of removing damage near the wellbore, hence restoring the natural permeability and greatly improving well productivity. Reservoir heterogeneity plays a significant role in the success of acidizing treatments because of its influence on damage removal mechanisms, and is strongly related to dissolution pattern of the matrix. The standard acid treatments are HCl mixtures to dissolve carbonate minerals and HCl- HF formulations to attack those plugging minerals, mainly silicates (clays and feldspars). A matrix acidizing apparatus for conducting linear core flooding was built and the operational procedure for safe, easy, and comprehensive use of the equipment was detailed. It was capable of reproducing different conditions regarding flow rate, pressure, and temperature. Extensive preliminary experiments were carried out on core samples of both Berea sandstone and Cream Chalk carbonate to evaluate the effect of rock heterogeneities and treatment conditions on acidizing mechanisms. The results obtained from the experiments showed that the temperature activates the reaction rate of HF-HCl acid mixtures in sandstone acidizing. The use of higher concentrations of HF, particularly at high temperatures, may cause deconsolidation of the matrix adversely affecting the final stimulation results. It was also seen that the higher the flow rate the better the permeability response, until certain optimal flow rates are reached which appears to be 30 ml/min for Berea sandstone. Highly permeable and macroscopic channels were created when acidizing limestone cores with HCl 15%. In carbonate rocks, there is an optimum acid injection rate at which the dominant wormhole system is formed.
152

A Study of Connection Between Manager¡¦s Core Competencies and Their Enhancement Methods in Case Company of China Steel Corporation.

Kuo, Hsin-chin 14 July 2008 (has links)
China Steel Corporation (CSC), established for more than thirty years, faces a problem of hundreds of middle level managers who will retire from the company in the near future, many successors are needed in the short term. Thus, how to quickly and effectively upgrade the managerment competency of new managers through various learning method becomes an important subject. This study takes CSC as a practical case and uses the Analytical Hierarchy Process (AHP) to analyze the connection between the manager core competencies and their enhancement methods .There are four core management competencies, including Planning& organization, Communications, Measurement & Evaluation and Executive Leadership, and there are four different learning methods also, including Job Experince ,Mentoring ,Classroom Lecturing,and Knowledge reading. A total of 24 employees in CSC were interviewed, including eight new (be a mentee), 8 senior managers (experienced persons) and 8 senior directors (be a mentor). It was proceeded by questionnaire supplemented with in-depth discussion.This study also takes the references from both domestic and international literature reviews. Hill (2007), professor of Harvard University, pointed out that there are five misconceptions of managing ability for a new manager,and he also emphasized the importance of an experienced manager¡¦s mentoring role. So, this study take the Mentoring learing method as the main topic to compare with the other enhancement methods. The study found that the Executive Leadership is the most important of four core management competencies in the case company CSC with a weighting 0.430. The Job experience and Mentoring are the most important of four enhancement methods with the weighting 0.357and 0.337. Moreover, The study result also indicates that the Mentoring is the best way to enhancement the competencies of the Executive Leadership. If the mentoring relationship can be set up at the very beginning stage when the new manager have promoted and be kept by one or two years, the learning effect will be more fruitful.
153

Design of The Rendezvous Mechanism In The Multi-Core AMBA System

Chang, Mu-Chi 06 August 2008 (has links)
In current chip multi-processors (CMPs), the on-chip network is a major factor affecting overall system performance. Different kinds of communication protocols vary from different communication architectures of current SOC designs. For example, the AMBA is master-slave architecture, which transacts and communicates the data of between the two CORE (Master) through the Memory (Slave). The architecture cost long time for load and store with memory. Hence, this paper design and implement a Rendezvous protocol on AMBA architecture, which is called Rendezvous of Advanced High performance Bus (RAHB), to let two processors can communicate with each other without memory reference overheads. The RAHB is compatible with the AHB architecture, and add Rendezvous communication protocol in the AMBA architecture to perform the direct transmission of data. Without referring the memory, the RAHB can improve the efficiency of communication in multi-core. For experimental evaluation, we evaluate the performance between RAHB and AHB, RAHB speedup (B/s) is average up to 50% for different data length and performance up 30% to 40% for executing test program.
154

none

Huang, Chi-Chou 26 July 2009 (has links)
From the view of industry's technological development trend, the basic theory researches and technologies were sprouted by advanced developed country in Europe and USA. The technical and practical application of these researches and technologies were developed by Japan. By the way of cost down, mass production was made in developing countries such as Taiwan and Korea. In order to reduce the manufacturing worker and workspace cost, most companies moved to under-developed countries such as China and Vietnam, etc. These industry companies are including textile, shoes, petrochemical, PCB, IC and LCD manufacturing companies. In recent years, the modern techniques countries such as USA and Japan paid a lot of attention on the influence power of China and neglected Taiwan and Korea. In order to reduce operating cost and aim at the consumer markets closed to 1,300 million people, they entered China and set up the factory directly. How should domestic small and medium-sized enterprises in Taiwan respond to this situation? When the small enterprise using specialization to overcome the problems such as small-scale and lacking-resource, the companies had cooperated with the flexible attitude to deal with the change in situation in order to stand firm gradually and make a profit steadily. At this moment, the companies have already built and constructed the key ability. They tried to improve rate of production, increase enterprise's income and gross value, desalinize the prosperous circulation fluctuation and disperse the risk. Except expanding the service stations and developing key technology, the companies turn a means with much angles of relevant technology and enter the potential profit pool to set up the second and three pillars in order to adopt many angle actions to extend the goals and get involve into the new business field. Meanwhile, the main methods used is to expand from the key ability of most manufacturers in the course of growing up. In the key process of expansion, it is the important topic to have key ability and levelage accurately reach new technology, new product and new field. The motive of this research combines the practical experience of the industry and relevant references. It also discusses the enterprise with key technology to make the environmental analysis, tactics of industry plan and execution in different business. The key succeed factor and failed reason is also compared to provide as the reference which company or the new undertaking of relevant industry's future assess of the cases to reduce the investment risk in the future and increase the probability of success. The main purpose of this analysis can be summarized as following: 1. The case study of the company is based on key ability to make different management tactics analysis that technology is correlated with. 2. In the case study of multi-business, it is analyzed and summarized on the key factors of the successful and unsuccessful cases. 3. Give some suggestions as the reference for the company or the relevant industry's factory to develop new business. In this investigation, the resource basic theory, multi-business motive and key successful factor are used to analyze the small and medium-sized enterprises that can create relevant technology for multi-business management. One precision coating professional manufacturing company is studied and analyzed by its tactics and key successful factor. In the results of this study, one can find that the company keep far from core ability during the process of multi-business operation will cause automatic control parameter lower and external variable larger. It leads the probability parameter of success to be smaller and difficult to master with greater risk. While getting into the new business, it will increase the success probability if one can integrate the upstream and downstream industry chain at the same time. Especially, the company obtains the support of original supplies or main customers with key raw materials and technology will develop the specialization and characteristic to make better profit.
155

The core value of Real Estate-Corporate Social Responsibility

Cheng, Jung-fa 20 August 2009 (has links)
Recently ¡§Corporate Social Responsibility (CSR)¡¨ has become one of the corporate competitiveness that international society took. How to combine Corporate Social Responsibility (CSR) with the maximization of profit and how to combine Corporate Social Responsibility (CSR) with operation strategies are an important topic that every enterprise in various countries concerned. This research is a qualitative study undertaken by means of case study and questionnaire/interview. Findings are as follows: Real Estate Brokerage in Taiwan has some cognition of Corporate Social Responsibility (CSR), but still has a big space to improve on carrying out Corporate Social Responsibility (CSR). Real Estate Brokerage is a trust industry which has great deal with people¡¦s property and investment involving a great amount of money, so Corporate Social Responsibility (CSR) has become Real Estate Brokerage¡¦s important factors of sustainable development. The Corporate Social Responsibility (CSR) should integrate into the enterprise¡¦s related domain to reach the Corporate Social Responsibility (CSR) and the enterprise profit maximization both. Employees of company continue to carry out Corporate Social Responsibility (CSR) together and integrate Corporate Social Responsibility (CSR) into company to create core competence. Only to do this, enterprises could reach the goal of sustainable development and be prosperous with society.
156

Polychlorinated biphenyls in sediment cores of Gaoping submarine canyon and its adjacent area

Tang, Chih-Cheng 06 September 2009 (has links)
This study presents the first reconstruction of pollution history of Polychlorinated biphenyls (PCBs) in Taiwan coast. Six sediment cores were collected from Gaoping submarine canyon and its adjacent area to investigate the distribution and source recognition of PCBs. The concentrations of PCBs in the cores from Gaoping canyon ranged 0.155--2.281 ng/g dry wt, whereas the maximum concentrations of PCBs reached 21.0 and 2.93 ng/g dry wt, respectively, in the cores from the northern and sourthern continental shelf of Gaoping canyon. The toxicological effects assessed by sediment quality guidelines (SQGs), show that only 2-10cm in core L27 exceeded the guideline value suggested by Förstner (6 ng/g), which indicated the sediment in this area had been polluted seriously and should not be disturbed. Overall, compared with studies in the world, the sediment PCB concentrations in Kao-Ping coastal areas were relatively low. Hierarchical Cluster Analysis identified the source of PCBs in the study area was a mixture of Aroclor 1016, Aroclor 1242 and Aroclor 1260. Similarity in vertical variations of total concentrations of PCBs among the six cores was observed and the trend is consistent with the history of the PCB usage in Taiwan. The drastic decrease in PCB concentrations around the late 1980s, clearly demonstrates the effectiveness of the ban of PCBs use in 1980 in Taiwan.
157

Analysis of Home Health Management Innovation and Core Capabilities

Lin, Chi-shan 27 January 2010 (has links)
In the 21st century, the rapid developments and growth of information and communication technology have triggered a new wave of Healthcare Industry. This study utilizes the secondary data analysis to analyze and generalize the processes, contents and models of health care management. In addition, discuss the changes in both healthcare informatics and medical related processes based on the innovations for the traditional models to the new home health care management models. Further, the standard of the evaluation are according to the expert consultations, to see the critical impacts of the innovations on the stakeholders: healthcare customers, healthcare providers and healthcare regulators are identified, so as to explore the core capabilities in these dimensions of the innovation. These results indicate that the innovations for home health management care are differences in the technological knowledge and business model aspects. We further identify five home health management models and their core business capabilities that are necessary for the stakeholders to cope with the changes, each appearing to address either technical or care aspects of the transformation. The findings have the potential to contribute to the understanding of impacts occurring in the change associated with the innovation in the care process and offer rich insights for the stakeholders to exploit the opportunities.
158

Public health informatics : a consensus on core competencies /

Richards, Janise Elaine, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 231-242). Available also in a digital version from Dissertation Abstracts.
159

Theoretical development of the core-drilling method for nondestructive evaluation of stresses in concrete structures /

Turker, Hakan T., January 2003 (has links)
Thesis (Ph. D.)--Lehigh University, 2003. / Includes vita. Includes bibliographical references (leaves 334-335).
160

Effect of verification core hole on the point bearing capacity of drilled shafts

Youn, Heejung, 1976- 05 October 2012 (has links)
For many projects involving drilled shafts, cores are required to be taken below the shaft base for visual identification of the underlying material. For example, the Texas Department of Transportation (TxDOT) requires a core length of at least 1.5 m (5 ft) or equal to the shaft diameter, whichever is greater, at the shaft base. Although the verification cores are to be extracted at the shaft base, The Department of Transportation of many states do not provide guidance to eliminate the effect of the verification core on the point bearing capacity. A recent study shows that the verification core hole is either filled with concrete in dry condition or with sand-gravel mixture in wet pour (Raibagkar, 2008). This finding is crucial because the point bearing capacity of drilled shafts with an empty hole at the base should be significantly lower than that of drilled shafts without verification core. Although the materials that fill in the verification core remove the risk of losing large point bearing capacity, the exposure of the core holes to air-drying may have an adverse effect on the point bearing capacity tipped in clay shales, especially when the basal material is susceptible to weathering. Therefore, the effect of the verification core on the point bearing capacity has been thoroughly investigated with emphasis on changes in the material properties of four clay shales (Del Rio Clay, Eagle Ford Shale, Taylor Marl, and Navarro Shale) in central Texas. The effect of verification core on the point bearing capacity of drilled shafts was investigated using finite element method (FEM) software, PLAXIS. The results from laboratory tests were converted to input material parameters for Mohr-Coulomb failure criterion, and the thickness of degraded zone around the core was interpreted from fullscale condition degradation tests. The load-displacement curves at the shaft base were created from PLAXIS analyses, and the point bearing capacities were obtained at 5%D and 10%D displacement from load-displacement curves. These capacities were used to calculate reduction factors that relate the point bearing capacity of the reference model (without a verification core) with that of the “core models” (with a verification core). The reduction factors are good indicators to determine if verification core had a positive or negative effect on the point bearing capacity. It was found that the reduction in point bearing capacity of “core models” is typically within 10% capacity of the reference model, and a maximum reduction of 14% was found for the Taylor Marl that was dried for 48 hours. / text

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