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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.
161

Research of Knowledge Creation & Spread In Company¡XCase Study

Hsu, Cheng-Tsai 20 August 2003 (has links)
Research of Knowledge Creation & Spread In Company -Case Study Abstract Knowledge management is one of the current hottest issues in academy and in practice. Nowadays, facing changeful and critical competitive environments, knowledge creation and spread management is the key resource to gain competitive advantage. The structure of this research is based on four modules of knowledge transformation; five-step modules in organization knowledge creation procedure and five circumstances of organization knowledge creation spiral, which advocated by Nonaka & Takeuchi (1994). The research designs contents of interviews in order to explore the influence of company competition in knowledge creation and spread management. The research also tries to integrate scopes of knowledge management researches by academic documents and deep interviews to explore and understand knowledge creation and spread management in company. The result shows most of companies know knowledge management is one of the internal core procedures. If it can establish a better knowledge management system earlier than competitor, then the company can develop it into a long-term major advantage by a spread of knowledge spiral even if it is tiny initially. In this case, manufacturers know customer¡¦s demands by feedback system management operating by customer claim service department. Then marketing and developing departments react punctually and supply suitable product and service in market. A tiny advantage can increase company¡¦s competition. This is increasing return economics. Keywoeds: Knowledge Management¡A Knowledge Creation & Spread ¡A Knowledge Conversion Model ¡A The Knowledge Spiral
162

Reserche of Falun Gong Transnational advocacy network

Chen, Chih-Hsiung 19 May 2008 (has links)
It is widely suggested that, in domestic environment, abundant private social network can make a huge impact in many aspect and vice versa. Then the same concept could also be applicable in international relations, and help mobilize sovereignty states? A rich literature also theorizes about the development of these phenomena among non-state actors that may signal the emergence of a new global civil society. While experts were continue discussing such subject, the transnational relationship scholars Margaret E. Keck and Kathryn Sikkink unveiled the concept of ¡§transnational advocacy network¡¨(hereafter TANs) being a tightly knit community of transnational members with shared believes and identity named ¡§issue-net work¡¨. Its strategies related to this activity in term of ¡§arguing power¡¨ and ¡§norm instrumental pressures¡¨. Then several questions can also be raised following its detail: How come did they make it success while others fail? Besides, if we ignored some factors during this ¡§network connecting¡¨ process¡HFinally, to what extent did they interact with sovereignty states? In the case of FaLun Gong group, its network structure is very complete and huge, but according to the consequence of its advocacy target ; suggested it fail to its campaign activity, then how would TANs theory help explain such consequence? This research observes the transformed of FLG TANs, and tries to tackle the above-mentioned questions. Therefore, may it could suggest some empirical experience from the outcome of this research, to those NGOs or non-state actors who devote in environment or human right campaign.
163

The study of peple's willingness to express opinion in Taiwan:The case of the fourth Taipei and Kaohsiung Mayoral Election

Chen, Ruei-De 30 July 2008 (has links)
Public opinion polls sometimes overestimate the majority and underestimate the minority, such as Taipei and Kaohsiung Mayoral Election of 2006. On one hand the study is based on spiral of silence theory to analyze the phenomenon, and on the other it tries to explore the other factors that may affect the voters¡¦ willingness to express opinion in Taipei and Kaohsiung city. According to findings, social integration effect isn¡¦t a main factor to affect people¡¦s willingness to express opinion in Taipei and Kaohsiung city. On the contrary, people¡¦s level of interpersonal communication, political efficacy and education in Taipei and interpersonal communication, political participation, political confidence and political efficacy in Kaohsiung city are important factors to increase people¡¦s willingness to express opinion. In addition, the study uses interactive variables to go a step further to explore social integration effect. The results show that the spiral of silence effect supports voters¡¦ behavior in Kaohsiung city, but doesn¡¦t in Taipei city.
164

The interpretive spiral: an analytical rubric for videogame interpretation

Whitson, Robert Henry 09 April 2012 (has links)
In this work, I propose an analytical rubric called the Interpretive Spiral designed to examine the process through which players create meaning in videogames, by examining their composition in three categories, across four levels of interaction. The most familiar of the categories I propose is the Mechanical, which refers to the rules, logic, software and hardware that composes the core of videogames. My second category, which I call the Thematic, is a combination of Arsenault and Perron's Narrative Spiral of gameplay, proposed in their Magic Cycle of Gameplay model (accounting for embedded text, videos, dialog and voiceovers) and Jason Begy's audio-visual level of his Tripartite Model of gameplay (accounting for graphics, sound effects, music and icons), though it also accounts for oft-neglected features such as interface and menu design. The third category, the Affective, refers to the emotional response and metaphorical parallels inspired by the combination of the other two levels. The first level of interaction I explore actually precedes gameplay, as it is common for players to begin interpreting games before playing them, and is called the Pre-Play Level of interpretation. Next I examine the Fundamental Level of interpretation, which entails the learning phase of gameplay. The Secondary Level of gameplay is the longest level of play and describes the shift from learning the game to informed, self-conscious play. The Third and final, elective level of interpretation, is where the player forms connections between his gameplay experience, and other concepts and experiences that exist outside of the game artifact. To put my model through its paces, I apply the model in its entirety to three influential and critically acclaimed videogames, and in part to several other titles.
165

Design and characterization of multi-layer coplanar waveguid[e] baluns and inductors [electronic resource] / by Khaled Obeidat.

Obeidat, Khaled. January 2003 (has links)
Title from PDF of title page. / Document formatted into pages; contains 178 pages. / Thesis (M.S.E.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: This work examined the design and characterization of multilayer coplanar waveguide baluns and inductors. This work derives a design procedure that helps RF engineers design cost effective multilayer coplanar waveguide (CPW) spiral balun that works in the frequency range 1-8 GHz. The accuracy of the developed procedure has been proven by designing two balun circuits of different dimensions and simulating them using available commercial software, Momentum (MoM) and Empire (FDTD). The simulation results have shown good balun performance over the desired frequency range. Furthermore some of the designed balun circuits have been fabricated and measured and the results agree with the simulations. The smaller balun (2.4 mm x 1.4 mm) with a minimum spacing of 25mm works very good in the frequency range 4-8 GHz with a 4 GHz operational bandwidth (OBW) and 5o phase difference and 0.5 dB amplitude imbalance. / ABSTRACT: The larger balun (5.6mm x 3.0 mm) with minimum spacing of 100mm works well in the frequency range 2-4 GHz with a 2 GHz operational bandwidth (OBW) and 10o phase difference and 0.5 dB amplitude imbalance. Such a large-size balun is suitable for a new fabrication technique called Direct-Write. This thesis focuses on techniques that can be used to enhance balun performance, it has been shown through this work that adding some capacitance at certain points in the balun circuit will decrease both the phase difference and the amplitude imbalance of the balun. Some of these techniques were discovered through the thesis work and the other techniques were used before, but for different balun structures. An additional study to the effect of the ground plane on the spiral inductor model is included herein. / ABSTRACT: Formulas for the inductance nominal value in the existing CPW ground plane for some spiral inductors are derived here, in addition to the derivation of an RF spiral inductor model that is independent of the ground plane. The importance of this model lies in its necessity in designing an antenna dipole loaded with lumped elements (in the absence of ground plane) to control the antenna electrical length without changing its physical length. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.
166

Internet operation of aero gas turbines

Diakostefanis, Michail 10 1900 (has links)
Internet applications have been extended to various aspects of everyday life and offer services of high reliability and security. In the Academia, Internet applications offer useful tools for the remote creation of simulation models and real-time conduction of control experiments. The aim of this study was the design of a reliable, safe and secure software system for real time operation of a remote aero gas turbine, with the use of standard Internet technology at very low cost. The gas turbine used in this application was an AMT Netherlands Olympus micro gas turbine. The project presented three prototypes: operation from an adjacent computer station, operation within the Local Area Netwok (LAN) of Cranfield University and finally, remotely through the Internet. The gas turbine is a safety critical component, thus the project was driven by risk assessment at all the stages of the software process, which adhered to the Spiral Model. Elements of safety critical systems design were applied, with risk assessment present in every round of the software process. For the implementation, various software tools were used, with the majority to be open source API’s. LabVIEW with compatible hardware from National Instruments was used to interface the gas turbine with an adjacent computer work station. The main interaction has been established between the computer and the ECU of the engine, with additional instrumentation installed, wherever required. The Internet user interface web page implements AJAX technology in order to facilitate asynchronous update of the individual fields that present the indications of the operating gas turbine. The parameters of the gas turbine were acquired with high accuracy, with most attention given to the most critical indications, exhaust gas temperature (EGT) and rotational speed (RPM). These are provided to a designed real-time monitoring application, which automatically triggers actions when necessary. The acceptance validation was accomplished with a formal validation method – Model Checking. The final web application was inspired by the RESTful architecture and allows the user to operate the remote gas turbine through a standard browser, without requiring any additional downloading or local data processing. The web application was designed with provisions for generic applications. It can be configured to function with multiple different gas turbines and also integrated with external performance simulation or diagnostics Internet platforms. Also, an analytical proposal is presented, to integrate this application with the TURBOMATCH WebEngine web application, for gas turbine performance simulation, developed by Cranfield University.
167

Tracking Fluid Flow in a Spinning Disk Reactor

Korzhova, Valentina N. 24 March 2006 (has links)
The flow of a liquid film over a rapidly rotating horizontal disk has many applications inmedical, industrial, and engineering fields. A specific example is the heat and mass transfer processes between expanded liquid and surrounded dense gas. Diferent wave regimes of a liquid film depend on a flow conditions such as the properties of a liquid, its initial speed,parameters of environment, etc. Therefore, experimental investigation of the film flow over a spinning disk is needed to both validate theoretical predictions and establish methods for fluid flow monitoring.This thesis presents novel video-based algorithms for detection and tracking wave structural data of the liquid film flowing over a spinning disk reactor. The algorithms are based on the spiral model of wave and the quasi-optimal method for estimation of a wave velocity as ill-posed problem. Their performance is compared with results predicted by the fluid dynamics based on the Navier-Stokes equations in the case of thin film.Using experimental video data, the developed models and algorithms allow investigators to estimate the characteristics of wave regimes such as wavelengths, inclination angles, and the radial and azimuthal velocity components of the fluid. The accuracy of estimated characteristics was analyzed. It was shown that average distance between consecutive two waves,their spiral shapes, and the radial velocities of waves confirm the theoretical results and predictions. In particular, computed wavelength is within 1% and a change of the inclination angles is within 2% of the predicted values.
168

On the arresting efficiency of spiral buckle arrestors for offshore pipelines

Huang, John Chih-Ming 05 November 2012 (has links)
Buckle arrestors are devices placed along an offshore pipeline for the purpose of arresting an incoming propagating buckle. Typically, buckle arrestors locally increase the pipe’s bending rigidity in the hoop direction. Spiral buckle arrestors are rods closely wound around the pipe for a number of turns and then welded at the ends to secure it in place. Spiral buckle arrestor have some key advantages to other designs in that they provide limited resistance to axial bending of the pipeline, and they can be wound on a continuous line away from free ends. This thesis uses a combination of experiments and modeling to study the effectiveness of spiral buckle arrestors. A series of experiments are conducted using 1.25-inch diameter SS-304 tubes with diameter-to-thickness ratios of 19 and 25. Stainless steel rods of four diameters are wound on tubes for a chosen number of turns and secured in place. A propagating buckle is subsequently initiated in the tube, engages the arrestor quasi-statically, is temporarily arrested, and eventually crosses the arrestor at a pressure defined as the crossover pressure. The crossover pressure was found to depend on the tube D/t and mechanical properties; and the rod diameter, number of turns, and mechanical properties. Finite element models are developed that enable the simulation of rod winding, buckle propagation, and buckle crossover. Local collapse is induced by external pressure and is propagated quasi-statically until it engages the arrestor. The pressure is increased until the buckle crosses the arrestor. The model is shown to reproduce the experimental observations and a large number of the measured crossover pressures with sufficient accuracy. Additional simulations were performed varying the rod diameter, numbers of turns, and tube D/t in order to enrich the database developed. This database was subsequently used to develop an empirical design formula for the arresting efficiency based on key nondimensional parameters of the problem. As was the case for the slip-on buckle arrestor, the arresting efficiency is bounded by the confined propagation pressure of the pipe. / text
169

Passive inductively coupled wireless sensor for dielectric constant sensing

Zhang, Sheng, active 2013 24 October 2013 (has links)
In order to address the challenges of capacitive sensing in harsh environment, self resonant passive wireless sensors are studied. The capacitive sensing elements based on interdigitated capacitor (IDC) sensor are used. A semi-empirical model providing accurate capacitance calculation for IDCs over a wide range of dimensions and dielectric constants is developed. An equivalent circuit model based on electric field distribution is proposed, leading to a closed form approximation for IDC capacitance calculation. The conductivity of the material under test is also considered and a model is proposed to calculate effective capacitance as a function of conductivity and measurement frequency. The model is used to study the design optimization of IDC sensor and suggested design procedure is proposed. To wirelessly interrogate the capacitive sensor, it is connected to an inductive element to form a resonant circuit, while the measurement is made at remote reader coil. Advantages and disadvantages of different type of resonant structure design are analyzed. In order to assist the design process, a SPICE circuit model is developed to estimate the resonant frequency of the self resonant sensor. Miniaturized sensors with different dimensions are designed, fabricated and tested. The sensor is integrated with silicon nanowire fabric coated with polymer. Measurements are made to illustrate the enhancement in sensing capability by integrating chemical selective material. / text
170

Relationship between biofilm removal and membrane performance using Dunedin reverse osmosis water treatment plant as a case study

Goldman, Joshua E 01 June 2007 (has links)
Membrane biofouling is a common occurrence in water treatment plants that utilize reverse osmosis (RO). As bacteria and biofilm material build up on the membrane surface, it becomes more difficult for clean water to permeate through the membrane, and more pressure is required to produce the same amount of water. When pressures become critically high, membranes must be cleaned. This process is expensive in terms of chemical cost, labor, and downtime. Even after membranes have been cleaned, they can re-foul quickly if the cleaning did not effectively remove the biofilm. The water treatment plant in Dunedin, FL, which uses RO for treating groundwater, has experienced membrane biofouling since it began operation in 1992. Without the means to systematically evaluate a multitude of cleaning strategies on the bench scale, cleaning optimization must be conducted on the production skid level, which restricts the evaluation of alternative protocols. This problem is typical for many RO plants. The objectives of this project are: (1) using a multi-level and systematic approach, develop cleaning strategies for biofouled membranes that will lead to improved cleaning and decreased operational costs; (2) develop other cleaning strategies that will add to the scientific knowledge base; (3) quantify the effects of improved protocols; and (4) determine the policy implications of developed protocols in terms of cost suitability to Dunedin and elsewhere in Florida. This project consists of three phases, with phases progressively more similar to the water production environment. In the first phase, a series of bench tests were performed in the laboratory. Fouled membrane swatches were soaked and agitated in different cleaning solutions for different lengths of time, at different temperatures and pH. Protein and carbohydrate assays were then performed on both the cleaning solution and the membrane swatch to determine which conditions yield most complete removal of protein and carbohydrate from the membrane surface. Results indicate that carbohydrate removal does not appear to depend strongly on pH or temperature. Protein removal increases with increasing pH and is slightly greater at higher temperatures. The second phase of testing employed a 4"x6" stainless steel flat-sheet module in which cleanings were performed under different conditions to document corresponding changes in water flux and salt rejection. Operational parameters were based on pertinent literature and optimization results from Phase 1. Results indicate that water flux increases in response to cleaning at increasing pHs and increasing temperatures with best performances occuring after 30 minutes of cleaning. Salt rejection appears to decrease with pH. The most effective cleaning protocols, determined through trials in Phases 1 and 2, were put to the test again in Phase 3 where cleanings were performed on a specially constructed single-element cleaning system (for 8.5" x 40" elements), designed to clean a membrane element in isolation. This phase also served as final verification of new cleaning protocols before implementation on the production scale. Results from this phase were inconclusive due to mechanical problems. A multi-level, systematic cleaning evaluation leads to better understanding of the dependence of biofilm material removal and membrane performance on critical factors such as temperature, pH, time of cleaning, and chemical dose, which results in improved cleaning protocols and ultimately cost savings to RO water utilities such as Dunedin.

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