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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.
371

The Research of Operation Process in Entertainment Industry-The Case of Billiards Playground in South Taiwan

Jiang, Cai-Ming 25 August 2005 (has links)
As the develop of economic in Taiwan, the working pressure increasing, people pay more and more attention to their leisure time than before, and they also want to find the balance point between the work and life. Based on the limitation of suitable place and working time in a city, it¡¦s not very easy to find a place to have a relaxation, that¡¦s why the entertainment industry growth up in the city. To keep the competition, the entertainment industry needs to take care the feeling of customer and also make the customer keep expending, the research will focus on the working process in entertainment industry, and try to find the important factors which can influence the customer satisfaction. Described the research results below. 1. Well communication: Before the new system be deployed, it is very important to communicate with all employee well, no matter how open the organization and culture is. The more that the manager understand the system, the earlier that the employee will accept, so the managers play key role for communication effectively. 2. Managing information technology system construction: Integrated information technology system will not only combine the information which from the front end and back end, but also improve the information exchange. 3. Managerial policies: No matter the communication process or information technology system construction, the organization need to build up a suitable environment for new policy, such as, provide training course for new system, increase the performance indicators.
372

BANDWIDTH-ENHANCEMENT DESIGNS OF SLOT-LOADED RECTANGULAR MICROSTRIP ANTENNAS

Sze, Jia-Yi 11 January 2001 (has links)
The bandwidth-enhancement characteristics of slot-loaded rectangular microstrip antennas constructed on a thin microwave substrate have been investigated in this dissertation. The primary design process about this topic is demonstrated. Firstly, a new antenna design idea is provided from pre-determined antenna design specifications or obtained antenna performances from the previous antenna design, which lead to a novel antenna configuration. From the results of the simulation software IE3DTM, the characteristics of this new antenna configuration are obtained and compared with the experimental results. The antenna configuration is also modified to achieve a final optimal design from the comparison results. The study of the single-feed dual-frequency rectangular microstrip antenna with a pair of bent slots is first presented. By embedding properly-designed slots on a rectangular microstrip patch, the impedance characteristics of this antenna design have been effectively changed to exhibit dual-resonant behavior, which result in the excitation of two adjacent resonant modes with similar radiation characteristics. Furthermore, the two resonant modes can be excited at frequencies very close to each other to form a wider operating bandwidth by embedding additional perturbation slots. Four successful antenna designs with different embedded-slot shapes for bandwidth enhancement have been implemented and discussed in this dissertation.
373

STUDIES OF BROADBAND PATCH ANTENNAS WITH AN AIR SUBSTRATE

Hsu, Wen-Hsiu 04 June 2001 (has links)
Novel broadband designs of patch antennas with an air substrate have been proposed in this dissertation. In the dual-frequency design, the study of single-fed dual-frequency microstrip antenna with a V-shaped slot has been first presented. As for the broadband patch antenna design, antennas with a U-shaped slot or a pair of wide slits can have an operating bandwidth more than 2.0 times that of a conventional one at a given operating frequency. The antenna bandwidth of then can be enhanced about 25%. In the designs of reducing cross-polarization, by using dual capacitive feeds with equal input powers, but with a 180¢X-phase shift, The cross-polarization radiation can be reduce about 10 to 15dB in the H-plane. Finally, A broadband shorted patch antenna fed by an aperture-coupled feed with an H-shaped coupling slot is proposed. By using an air substrate of thickness about 0.07 free-space wavelength of the center operating frequency, the proposed antenna can have an impedance bandwidth of about 26.2%. And the antenna design reduced the antenna size to be 40%~50%of the simple case.
374

A cost benefit analysis for the bicycle as a transportation alternative

Stanislaw, Andrew C. January 1996 (has links)
Cost benefit analysis is the conventional method of evaluating automobile transportation improvements. This study examined traditional automobile evaluation methods and applied the same techniques to bicycle transportation projects. Cost data from recent research is summarized and eleven costs (five internal and six external) were estimated. The cost estimates are used to calculate automobile and bicycle costs per mile of travel. A case study of a hypothetical corridor is used to demonstrate how the transportation costs can be applied to specific planning problems. The case study explores what effect shifts in modal distribution would have on the cost effectiveness of automobile and bicycle alternatives. The findings of the study begin to question the underlying premises of traditional cost benefit analysis in transportation projects. The study suggests that conventional analysis is fundamentally flawed and biased toward automobile transportation. / Department of Urban Planning
375

FPGA interconnection networks with capacitive boosting in strong and weak inversion

Eslami, Fatemeh 22 August 2012 (has links)
Designers of Field-Programmable Gate Arrays (FPGAs) are always striving to improve the speed of their designs. The propagation delay of FPGA interconnection networks is a major challenge and continues to grow with newer technologies. FPGAs interconnection networks are implemented using NMOS pass transistor based multiplexers followed by buffers. The threshold voltage drop across an NMOS device degrades the high logic value, and results in unbalanced rising and falling edges, static power consumption due to the crowbar currents, and reduced noise margins. In this work, circuit design techniques to construct interconnection circuit with capacitive boosting are proposed. By using capacitive boosting in FPGAs interconnection networks, the signal transitions are accelerated and the crowbar currents of downstream buffers are reduced. In addition, buffers can be non-skewed or slightly skewed to improve noise immunity of the interconnection network. Results indicate that by using the presented circuit design technique, the propagation delay can be reduced by at least 10% versus prior art at the expense of a slight increase in silicon area. In addition, in a bid to reduce power consumption in reconfigurable arrays, operation in weak inversion region has been suggested. Current programmable interconnections cannot be directly used in this region due to a very poor propagation delay and sensitivity to Process-Voltage-Temperature (PVT) variations. This work also focuses on designing a common structure for FPGAs interconnection networks that can operate in both strong and weak inversion. We propose to use capacitive boosting together with a new circuit design technique, called Twins transmission gates in implementing FPGA interconnect multiplexers. We also propose to use capacitive boosting in designing buffers. This way, the operation region of the interconnection circuitry is shifted away from weak inversion toward strong inversion resulting in improved speed and enhanced tolerance to PVT variations. Simulation results indicate using capacitive boosting to implement the interconnection network can have a significant influence on delay and tolerance to variations. The interconnection network with capacitive boosting is at least 34% faster than prior art in weak inversion. / Graduate
376

Die Abwehr von Terrorgefahren im Luftraum im Spannungsverhältnis zwischen neuen Bedrohungsszenarien und den Einsatzmöglichkeiten der Streitkräfte im Inneren unter besonderer Berücksichtigung des Luftsicherheitsgesetzes

Paulke, Katja January 2005 (has links)
Zugl.: Berlin, Humboldt-Univ., Diss., 2005
377

Interaktive und dynamische Visualisierung für die chirurgische Ausbildung und Interventionsplanung

Bade, Ragnar January 2008 (has links)
Zugl.: Magdeburg, Univ., Diss., 2008
378

Investigating the adoption of ring operation in LV networks with PV systems

Aydin, Muhammed Sait January 2017 (has links)
The ambitious governmental policies, particularly in Europe, in pursuit of established energy targets require an increase in distributed generation. As a result, photovoltaic (PV) technologies have emerged, predominantly at residential Low Voltage (LV) feeders. However, PV rich LV feeders are highly likely to pose technical challenges such as significant voltage rise and thermal overloading. This inevitably limits the volume of PV systems that can be hosted on LV feeders. Therefore, the deployment of solutions that can enable feeders to accommodate greater volumes of PV systems without having any technical issues is crucial. This thesis, consequently, thoroughly investigates one of the potential solutions: transforming the radial operation of LV feeders into ring operation. European-style LV feeders are typically operated in a radial fashion and yet are designed to be reconfigurable with neighbouring feeders. It is, therefore, essential to identify the best pairing option (of PV rich LV feeders) in a practical and straightforward manner due to the large number of existing LV feeders in a given Distribution Network Operator (DNO) area. This thesis proposes a generic innovative methodology to enable DNOs to straightforwardly identify the best pairing feeder; a decision-making tool to facilitate the rapid uptake of PV systems. To accomplish this goal, an impact assessment of a set of real residential LV feeders is carried out to identify the first technical issue/constraint that limits their hosting capacity. Next, regression analyses are carried out to gain an understanding of the relation between this first occurrence of technical issue/constraint and the corresponding level of PV penetration. The most practical and adequately accurate metric needs to be chosen. Feeders are then classified based on the range of metrics to cover all possible pairing cases. Finally, the ring operation of feeders in each class is analysed and hosting capacities are compared to those of radial ones. This process creates a practical matrix from which DNOs can easily identify the best pairing feeders. DNOs are likely to be hesitant to adopt permanent ring operation as it is not typically adopted in traditional LV feeders. Therefore, the switch located between feeders can be operated over time (i.e., dynamic ring operation) to reduce the duration for which ring operation is in place. It is, however, challenging to identify the most favourable control strategy. This thesis proposes different strategies for dynamic ring operation. Note that the most preferable control strategy is that which preserves the benefits of permanent ring operation with the minimum duration of ring operation and minimum number of switching. To achieve this, four different control strategies are explored-using different control cycles and considering hosting capacity, duration and switching. The best control strategy is found to be able to increase hosting capacity as permanent ring operation, reduce switching actions and minimise duration of ring operation compared to other proposed strategies and, crucially, operate ring operation only when it is truly needed. Finally, this thesis investigates the use of ring operation with an LV on-load tap changer (OLTC) as this is recently available voltage control technologies and is increasingly drawing the attention of DNOs. Two approaches are investigated to increase hosting capacity and limit ring operations: the use of the switch and OLTC are controlled separately using local measurements (i.e., localised) and their simultaneous control at the LV transformer level (i.e., centralised). The latter gives the priority to the OLTC to minimise the duration of the ring operation. The assessments are extended to cover an integrated medium and low voltage network to obtain more realistic results. The results show that centralised approach provides better performance considering hosting capacity, the number of switching/tap actions and the duration of ring operation.
379

Operation Moked : Sexdagarskriget – Överraskning inom de israeliska luftoperationerna / Operation Moked : The Six Day War – Surprise and the Israeli Aerial Operations

Damm, Douglas January 2013 (has links)
The research regarding the six day war and the aerial operations named Operation Moked is extensive but there are certain shortcomings in the research that examines both the operation and the principle of surprise. The aim of this paper is to contribute to this research by utilising existing military theories on the principle of surprise in order to identify indicators that are representative of surprise.  These indicators are thereafter used in a study of Operation Moked in order to examine the extent of in which the principle was utilised. The result of this research goes to show that the principle of surprise was utilised in great extent by Israel during Operation Moked. / Det har bedrivits mycket forskning kring Sexdagarskriget och det lyckade israeliska luftanfallet Operation Moked men det finns vissa brister i forskningen på operationen kopplat till krigföringsprincipen överraskning. Denna uppsats syftar till att bidra till detta forskningsläge genom att använda militära teoribildningar kring principen överraskning och bryta ut indikatorer på vad som kännetecknar principen. Dessa indikatorer används sedan i en studie av Operation Moked för att undersöka i vilken utsträckning principen tillämpades. Resultatet av denna undersökning påvisar att överraskning tillämpades i stor utsträckning av Israel under Operation Moked.
380

Optimization/Simulation Model for Determining Real-Time Optimal Operation of River-Reservoirs Systems during Flooding Conditions

January 2015 (has links)
abstract: A model is presented for real-time, river-reservoir operation systems. It epitomizes forward-thinking and efficient approaches to reservoir operations during flooding events. The optimization/simulation includes five major components. The components are a mix of hydrologic and hydraulic modeling, short-term rainfall forecasting, and optimization and reservoir operation models. The optimization/simulation model is designed for ultimate accessibility and efficiency. The optimization model uses the meta-heuristic approach, which has the capability to simultaneously search for multiple optimal solutions. The dynamics of the river are simulated by applying an unsteady flow-routing method. The rainfall-runoff simulation uses the National Weather Service NexRad gridded rainfall data, since it provides critical information regarding real storm events. The short-term rainfall-forecasting model utilizes a stochastic method. The reservoir-operation is simulated by a mass-balance approach. The optimization/simulation model offers more possible optimal solutions by using the Genetic Algorithm approach as opposed to traditional gradient methods that can only compute one optimal solution at a time. The optimization/simulation was developed for the 2010 flood event that occurred in the Cumberland River basin in Nashville, Tennessee. It revealed that the reservoir upstream of Nashville was more contained and that an optimal gate release schedule could have significantly decreased the floodwater levels in downtown Nashville. The model is for demonstrative purposes only but is perfectly suitable for real-world application. / Dissertation/Thesis / Doctoral Dissertation Civil Engineering 2015

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