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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

Duty Cycle Control In Wireless Sensor Networks

Yilmaz, Mine 01 September 2007 (has links) (PDF)
Recent advances in wireless communication and micro-electro-mechanical systems (MEMS) have led to the development of implementation of low-cost, low power, multifunctional sensor nodes. These sensor node are small in size and communicate untethered in short distances. The nodes in sensor networks have limited battery power and it is not feasible or possible to recharge or replace the batteries, therefore power consumption should be minimized so that overall network lifetime will be increased. In order to minimize power consumed during idle listening, some nodes, which can be considered redundant, can be put to sleep. In this thesis study, basic routing algorithms and duty cycle control algorithms for WSNs in the literature are studied. One of the duty cycle control algorithms, Role Alternating, Coverage Preserving, and Coordinated Sleep algorithm (RACP) is examined and simulated using the ns2 simulation environment. A novel duty cycle control algorithm, Sink Initiated Path Formation (SIPF) is proposed and compared to RACP in terms of sleep sensor ratio and time averaged coverage.
212

The Effect of National Defense Substitute Service on Enterprise From a Human Resources Perspective

Liu, Pei-Yu 26 August 2008 (has links)
The Defense Industry Reserve Duty System¡]DIRDS¡^has been used in Taiwan for many years. This program enables science and technology industries to recruit talented people, who can contribute to the defense industry and the high-tech industries without interruption by regular military service. This study uses quantitative methodology and interviews with human resources and R&D managers to determine how this program has effected high-tech enterprises from a human resources perspective. Results of this study showed that DIRDS recruits exhibited four characteristics: high stability, high quality, high educational background, and high consistency with industry requirements. Due to these four characteristics, DIRDS recruits have become an important source of IT talent. DIRDS recruits can bring significant growth to R&D efforts and enhance the energy of development. The Defense Industry Reserve Duty System can thus help reduce manufacturing costs, improve operational effectiveness, and raise the prestige of corporate brands. Further analysis and discussion of our results show that for human resources planning, work arrangement with DIRDS recruits should be combined with the company's long term objectives. Recruitment and selection should be focused and strategic since DIRDS targets specialized skills. Training and development should focus on practical or on job training that is tailored to the abilities and temperament of the DIRDS recruit.
213

Essays on parallel imports,the government policies on IPRs,anti-dumping duty and quality-related R&D

Ting, Lung-Lu 23 June 2009 (has links)
none
214

Does anybody care? : public and private responsibilities in Swedish eldercare 1940-2000 /

Brodin, Helene, January 2005 (has links)
Thesis (doctoral)--Umeå University, 2005. / Includes bibliographical references.
215

Plato's Crito a deontological reading /

Sklar, Lisa Dawn. January 2009 (has links)
Thesis (M.A.)--University of Central Florida, 2009. / Adviser: Nancy Stanlick. Includes bibliographical references (p. 54-58).
216

Understanding college students' purchase behavior of fashion counterfeits fashion consciousness, public self-consciousness, ethical obligation, ethical judgment, and the theory of planned behavior /

Lee, Jinhwa. January 2009 (has links)
Thesis (M.S.)--Ohio University, November, 2009. / Title from PDF t.p. Includes bibliographical references.
217

Three essays on health economics and international trade

Yousefi, Kowsar 08 October 2012 (has links)
This dissertation contains two chapters on law and economics and one chapter on international trade. An important but under-researched issue for medical malpractice (med-mal) litigation is how physicians' previous medical malpractice experiences affect their behaviour. Using Florida data on closed med-mal claims, I find that if physicians have prior paid claims, their current litigation is resolved faster and is associated with less cost. Having a prior payout does not significantly predict the likelihood or the amount of the current payout. This suggests that ``learning'' occurs as a result of prior med-mal experience. As a theoretical motivation, I developed a dynamic version of the divergent expectations (DE) litigation model. The model predicts, consistent with the data, that physicians have a more realistic analysis of med-mal litigation if they have prior experience. Many robustness checks are carried out to test the results, including using a fixed effect framework, to which the results are robust. In the second chapter, we investigate the impact of ``duty to settle'' rule in predicting patterns in data. Prior models and studies of settlement ignore the insurer's ``duty to settle'' -- the obligation to settle within policy limits if it would be unreasonable to refuse a within-limits settlement offer. We incorporate the duty to settle into a structural model of settlement of medical malpractice claims, and then estimate the model using maximum likelihood methods applied to a Texas closed claims database. Both the data and our model predict: a mass of cases with a settlement demand by the plaintiff exactly at limits; a smaller but still sizeable mass of cases with settlement exactly at limits; very few above-limits payments by insureds; and when above-limits payments are made, they are often by insurers. The model does a reasonable job in predicting data moments, including fractions of cases settled at limits, settled above limits, and tried. Using the model in counterfactual analysis, we predict: (i) with no duty to settle, more cases will be tried; (ii) with strict insurer liability for not settling within limits, there will be fewer trials and more above limits payments by insurers; and (iii) the duty to settle will rarely cause insurers to pay more than the expected value of claims. The third chapter of this dissertation is on international trade. There is a well established literature on the impact of sovereign debt renegotiation on bilateral trade, including Rose (2005) among others. However, there is no study that disentangles impacts of renegotiation on the intensive and extensive margins, where the former is the trade volume of established bilateral trading relationships and the latter is the number of established relationships. This study employs the UNComTrade dataset and debt renegotiation data from the Paris Club for over 150 countries in order to address the impact of a debt renegotiation on the extensive margin of trade. This paper finds that bilateral trade volume declines following a sovereign debt renegotiation. The result is robust to the use of trade lags as instrumental variables to address endogeneity. Consistent with the trade literature, this study documents a negative impact of a debt renegotiation on the trade value using the Tobit approach in a fixed effect model, to appropriately handle censored data. Interestingly, a comparison between the marginal impacts of a debt renegotiation on the extensive and the intensive margins shows that the former effect has at least the same magnitude as the latter. / text
218

Utilizing Look-Ahead Information to Minimize Fuel Consumption and NOx Emissions in Heavy Duty Vehicles

Florell, Christoffer January 2015 (has links)
Producing more fuel efficient vehicles as well as lowering emissions are of high importance among heavy duty vehicle manufactures. One functionality of lowering fuel consumption is to use a so called \emph{look-ahead control strategy}, which uses the GPS and topography data to determine the optimal velocity profile in the future. When driving downhill in slopes, no fuel is supplied to the engine which lowers the temperature in the aftertreatment system. This results in a reduced emission reduction capability of the aftertreatment system. This master thesis investigates the possibilities of using preheating look-ahead control actions to heat the aftertreatment system before entering a downhill slope, with the purpose of lowering fuel consumption and $NO_x$ emissions. A temperature model of a heavy duty aftertreatment system is produced, which is used to analyse the fuel consumption and $NO_x$ reduction performance of a Scania truck. A Dynamic Programming algorithm is also developed with the purpose of defining an optimal control trajectory for minimizing the fuel consumption and released $NO_x$ emissions. It is concluded that the Dynamic Programming optimization initiates preheating control actions with results of fuel consumption reduction as well as $NO_x$ emissions reductions. The best case for reducing the maximum amount of fuel consumption results in 0.14\% lower fuel consumption and 5.2\% lower $NO_x$ emissions.
219

För barnets bästa : En kvalitativ studie om pedagogers syn på sin anmälningsskyldighet

Birelius, Jennie January 2010 (has links)
This study is aimed at finding out how nursery and pre-school teachers carry out their obligation to report suspected child abuse, and their views on the issue. The study was alsoa imed at highlighting any difficulties teachers might have when dealing with children who arem istreated. In addition, the study examines the impact on teachers and children when thet eachers decide to either report or not report abuse. The main issues addressed by this study are:   Are pre-school and nursery teachers aware of their duty to report suspected child abuse and what are their opinions regarding this duty? How do the teachers claim they behave if obliged to report and what difficulties dothey encounter? In order to find the answer to these questions, qualitative interviews were made with eight pre-school teachers. The empirical evidence has been put in relation to theories of action and communication as well as to previous research in the area that concerns children who are mistreated. The study demonstrates the complexities that the duty to report child abuse creates and how the ambivalence that arises can inhibit a teacher’s actions. Fear of the consequences, regardless of whether the report is made or not, ultimately lead to paralysis, something which the conclusion also shows. Some of the conclusions drawn are that the support to teachers must improve in terms of better co-operation between pre-schools and social services. Moretime should also be set aside for training and for discussions with colleagues. The duty toreport suspected child abuse needs to be addressed in a way that makes it less daunting in order to encourage more teachers to do so. Apprehension regarding the possible consequences that would arise from reporting child abuse should not deter a teacher from helping a  vulnerable child.
220

Distributed Road Grade Estimation for Heavy Duty Vehicles

Sahlholm, Per January 2011 (has links)
An increasing need for goods and passenger transportation drives continued worldwide growth in traffic. As traffic increases environmental concerns, traffic safety, and cost efficiency become ever more important. Advancements in microelectronics open the possibility to address these issues through new advanced driver assistance systems. Applications such as predictive cruise control, automated gearbox control, predictive front lighting control, and hybrid vehicle state-of-charge control decrease the energy consumption of vehicles and increase the safety. These control systems can benefit significantly from preview road grade information. This information is currently obtained using specialized survey vehicles, and is not widely available. This thesis proposes new methods to obtain road grade information using on-board sensors. The task of creating road grade maps is addressed by the proposal of a framework where vehicles using a road network collect the necessary data for estimating the road grade. The estimation can then be carried out locally in the vehicle, or in the presence of a communication link to the infrastructure, centrally. In either case the accuracy of the map increases over time, and costly road surveys can be avoided. This thesis presents a new distributed method for creating accurate road grade maps for vehicle control applications. Standard heavy duty vehicles in normal operation are used to collect measurements. Estimates from multiple passes along a road segment are merged to form a road grade map, which improves each time a vehicle retraces a route. The design and implementation of the road grade estimator are described, and the performance is experimentally evaluated using real vehicles. Three different grade estimation methods, based on different assumption on the road grade signal, are proposed and compared. They all use data from sensors that are standard equipment in heavy duty vehicles. Measurements of the vehicle speed and the engine torque are combined with observations of the road altitude from a GPS receiver, using vehicle and road models. The operation of the estimators is adjusted during gearshifts, braking, and poor satellite coverage, to account for variations in sensor and model reliability. The estimated error covariances of the road grade estimates are used together with their absolute positions to update a stored road grade map. Highway driving trials show that the proposed estimators produce accurate road grade data. The estimation performance improves as the number of road segment traces increases. A vehicle equipped with the proposed system will rapidly develop a road grade map for its area of operation. Simulations show that collaborative generation of the third dimension for a pre-existing large area two-dimensional map is feasible. The experimental results indicate that road grade estimates from the proposed methods are accurate enough to be used in predictive vehicle control systems to enhance safety, efficiency, and driver comfort in heavy duty vehicles. The grade estimators may also be used for on-line validation of road grade information from other sources. This is important in on-board applications, since the envisioned control applications can degrade vehicle performance if inaccurate data are used. / QC 20110408

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