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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.
351

Survey of Pathogen Interventions and Best Practices Used by Beef Harvesters and Processors

Langley, Scott P. 2010 August 1900 (has links)
A survey was developed and sent out to each sector of the beef industry (slaughter, non-intact processing and grinding) by using the FSIS Meat, Poultry and Egg Product Inspection Directory. Survey questions were specific to processes and interventions being applied, and the use and familiarity with Industry Best Practices documents for beef processing. Returned completed surveys. A total of 469 beef processing operations responded and of survey respondents, 119 establishments were called and asked additional questions. Critical Control Points (CCPs) and testing for E. coli O157:H7 were common discussion point during phone calls. Plant visits were made to confirm the answers that were provided in the written survey. Plants that further processed beef were found to need to reassess their HACCP plan based on their response to the question, "Is E. coli O157:H7 a reasonably likely to occur food safety hazard?" E. coli O157:H7 is considered an adulterant in the products that they produced if they answered yes to this question. Based on survey responses, slaughter establishments were using available technologies to reduce or eliminate possible microbiological contamination. Further process operations, especially those plants that produced intact steaks and roasts, marinated/enhanced steaks and roasts, and plants that produced needle/blade tenderized steaks and roasts, used documentation such as supplier purchasing specifications instead of using processes to control, reduce, or eliminated microbiological food safety hazards. Industry Best Practices were being utilized most frequently by slaughter and ground beef operations. Plants that further process beef still need to implement the use of the Industry Best Practices specific to them. Plants used testing for E. coli O157:H7 throughout the beef industry regardless of plant size or type.
352

Compliance and Best Practices in Transition Planning: Effects of Disability and Ethnicity

Landmark, Leena Jo 2009 December 1900 (has links)
It is well known that individuals with disabilities have poor postsecondary outcomes. As a result, state and local education agencies are held accountable for the post-school achievements of their students with disabilities. The purposes of this study were (a) to determine the extent to which the transition components of Individualized Education Program (IEP) documents were compliant with the transition requirements of the Individuals with Disabilities Education Improvement Act of 2004 (IDEIA), (b) to determine the extent to which the transition components of the IEP documents provided evidence of best practices, (c) to determine the effects that disability category and ethnicity had on compliance and practices as evidenced in the transition components of the IEP documents, and (d) to determine the relationship between overall compliance and best practices. The sample for the study included 212 secondary students who had a developmental disability, an emotional disorder, or a learning disability and who were African American, Caucasian, or Hispanic. Several types of analyses were conducted including descriptive, multiple logistic regression, and Spearman's rho correlation. The overall level of compliance was 2.03 (SD = 1.238). The range of possible scores was 0 - 5, with 0 indicating that none of the components of compliance were 100 percent compliant, and 5 indicating that all of the components were 100 percent compliant. The overall level of best practices as evidenced in the IEP documents was 4.89 (SD = 1.569). The range of possible scores was 0 - 8, with 0 indicating that there was no evidence of any of the practices in the IEP document, and 8 indicating that evidence of all the practices was found in the IEP document. A student's disability category and ethnicity were found to be influencing characteristics for increasing or decreasing the probability of an IEP document being compliant and/or having evidence of best practices. A statistically significant correlation of r = .429 was found between the overall levels of compliance and best practices, indicating that as the level of compliance increased, so too did the level of best practices evident in the IEP document.
353

Simulating and Optimizing Storm Water Management Strategies in an Urban Watershed

Damodaram, Chandana 2010 December 1900 (has links)
Land development transforms the natural landscape and impacts in stream ecosystems and downstream communities as it alters the natural flow regime. An increase in impervious areas results in higher volumes of storm water runoff, reduced time to peak, and more frequent flooding. Best Management Practices (BMP) and Low Impact development (LID) are a few of the set of measures which are used to mitigate the impact of urbanization. Peak flow, runoff volume are few of the conventional metrics which are used to evaluate the impact and performance of these storm water management strategies on the watershed. BMP are majorly used to control the flood runoff but results in the release of large volumes of runoff even after the flood wave passed the reach and LIDs are used to replicate the natural flow regime by controlling the runoff at the source. Therefore need to incorporate a metric which includes the timing and area being inundated needs to be considered to study the impact of these strategies on the downstream. My proposed research will focus on simulating the Low Impact Development (LID) techniques like permeable pavements and rainwater harvesting on an urbanized watershed using a curve number approach to quantify the hydrologic performance of these strategies on the watershed. LID, BMPs, and combined strategies are introduced for retrofitting existing conditions and their hydrologic performance is accessed based on the peak flow and a new metric Hydrologic Footprint Residence. A simulation optimization framework would be developed which identifies cost effective LID options that maximize the reduction of peak flow from the existing condition design storms while meeting budget restrictions. Further LID and BMP placement is included in the optimization model to study the impact of the combined scenario on the storm water management plans and their performance based on different storms and corresponding budget. Therefore a tradeoff can be illustrated between the implementation cost and the hydrological impact on the watershed based on the storm water management approach of using only LID and combination of LID and BMP corresponding to varied spectrum of design storm events.
354

Analysis of 2009 ENR Best Projects in Texas to Determine the Impact of Project Delivery System Used

Rajan, Navaneethan 2010 December 1900 (has links)
Competitive Bidding, Competitive Sealed Proposal, construction management agency, construction management at risk, Design-Build, Design-Build-Bridging, and job order contracting are seven project delivery methods that are commonly used in the state of Texas today. This paper empirically compares the cost, schedule, and change order management performance of these project delivery methods in 2009 Engineering News Record (ENR) Best Construction Projects in Texas, using the data collected from the projects representative of the population. Also information is collected on lessons learned from these projects. The thesis included development of survey instrument, getting approval from Institutional Review Board (IRB), data collection from the industry, statistical analysis and inferences. Based on the data collected, project performances were measured in terms of five identified variables and then plotted in the form of probability distribution curves to understand the characteristics of the target population. Then, the results were grouped into six categories based on project delivery methods used and compared to understand their impacts on these projects. Findings revealed predominant usage of CM at Risk PDM, and better cost and schedule performance of CM at Risk, Design-Build, and Owner customized PDM. Detailed performance metrics, results, interpretations and conclusions are presented.
355

Robust Run Order for Experimental Designs in Simple Linear Regression with MA Errors

Chiou, Guo-huai 16 July 2004 (has links)
In this work, a method to choose the best run order for a given experimental design is proposed, for the simple linear regression model with MA errors. More specifically we investigate the best run order of an uniform design when errors follow a MA(1) or a subset MA(k) process where k is a positive integer. The correlation matrix P resulting from the errors is usually difficult to obtain a good estimate. Using the change of variance function(CVF) to see the relation of the uncorrelated and the serially correlated errors. Criterion proposed by Zhou (2001), we find the best run order of the uniform design on [-1,1] to minimize the robust criterion, |CVF|. We will display the permutation of a run order after rearrangement by our method and show how the structure is decomposed into three categories to solve the problem.
356

Enhancing Petroleum Recovery From Heavy Oil Fields By Microwave Heating

Acar, Cagdas 01 June 2007 (has links) (PDF)
There are many heavy oil reservoirs with thin pay zones (less than 10 m) in the world and in Turkey. Conventional steam injection techniques are not costeffective for such reservoirs, due to excessive heat loss through the overburden. Heat losses can be minimized through controlled heating of the pay zone. One such way is to introduce heat to the reservoir in a controlled manner is microwave heating. Laboratory studies on microwave heating of a scaled model of a heavy oil reservoir with a thin pay zone are presented with an economical feasibility of the method. In this thesis, three different conceptual oil reservoirs from south east Turkey are evaluated: Bati Raman (9.5 API) and &Ccedil / amurlu (12 API) heavy crude oils and paraffinic Garzan (26 API)crude oil. Using a graphite core holder packed with crushed limestone with crude oil and water microwave effects of operational parameters like heating time and waiting period as well as rock and fluid properties like permeability, porosity, wettability, salinity, and initial water saturation are studied. The main recovery mechanisms for the experiments are viscosity reduction and gravity drainage. An analytical model is developed by coupling heat equation with the electromagnetic dissipated power per unit of volume based in Maxwell&#039 / s equation successfully models the experiments for temperatures less than the pyrolysis temperature is presented. Also the experiments are scaled to the model by geometric similarity concept. In economic evaluation, the cost of oil is calculated based on domestic electricity prices.
357

Connectionless Traffic And Variable Packet Size Support In High Speed Network Switches: Improvements For The Delay-limiter Switch

Akcasoy, Alican 01 June 2008 (has links) (PDF)
Quality of Service (QoS) support for real-time traffic is a critical issue in high speed networks. The previously proposed Delay-Limiter Switch working with the Framed-Deadline Scheduler (FDS) is a combined input-output queuing (CIOQ) packet switch that can provide end-to-end bandwidth and delay guarantees for connection-oriented traffic. The Delay-Limiter Switch works with fixed-size packets. It has a scalable architecture and can provide QoS support for connection-oriented real-time traffic in a low-complexity fashion. The Delay-Limiter Switch serves connectionless traffic by using the remaining resources from the connection-oriented traffic. In this case, efficient management of the residual resources plays an important role on the performance of the connectionless traffic. This thesis work integrates new methods to the Delay-Limiter Switch that can improve the performance of the connectionless traffic while still serving the connection-oriented traffic with the promised QoS guarantees. A new method that makes it possible for the Delay-Limiter Switch to support variable-sized packets is also proposed.
358

Research on the law of legitimate and illegitimate children Between Taiwan and China

Kuo, Li-jun 06 January 2009 (has links)
Since Convention on the Rights of the Child of the United Nations are released, children's best interests becomes the highest principle for every state having legal system to deal with children's affairs. So we can say that the first serious mission of the subject of modern parent and tot's relation is protecting minor children's interests, then keeping the marriage and family peace and stable identity relations and etc. is the next. And in order to reach the above-mentioned purpose, the numerous countries have begun to examine their law of the marriage and family, even some advanced countries have abolished the differentiation between legitimate and illegitimate children too, in order to reach the demand for this two equalization. Now people of our country and mainland China ( what follows we call them two sides) contact with each other frequently, and then the extramarital sexual intercourse of people of two sides becomes numerous, and the quantity of the legitimate children also increases year by year. Base this, the announcement of the Equal Principle between legitimate and illegitimate children in mainland China marriage law has a deep meaning, but when we review our country, we find that our law about children's affairs has no response for the above-mentioned things. Even now our law about children's affairs still maintain the differentiation of legitimate and illegitimate children and also especially discriminate against the children of the mainland China in "The ordinance of people's relationship between Taiwan and mainland China ". So this thesis's aim is checking the legal system related to legitimate and illegitimate children of two sides by the standard namely with the children's best interests and look over them to find they observe the standard namely with the children's best interests or not. By the way, this thesis will try to find the reason and the cause that helping legal system about legitimate and illegitimate children stand out ,and try to find the real way to make legitimate children equal with illegitimate children in the modern status which has varied family type and varied pattern of both sexes getting along with each other. To this end, the thesis want to set up a new ¡§legitimate children presumption¡¨system to adapt to the above-mentioned purpose, and doesn't make children unequal just because their parents aren't husband and wife , and our law ¡]or mainland China's law¡^about children's affairs will juxtapose advanced countries.
359

The Worst-case and Best-case Coverage Problems in Wireless Sensor Networks

Hou, Yung-tsung 10 June 2009 (has links)
Wireless sensor networks provide a wide range of applications, such as environment surveillance, hazard monitoring, traffic control, and other commercial or military applications. The quality of service provided by a sensor network relies on its coverage, i.e., how well an event can be tracked by sensors. This research studies issues about sensor coverage: (1) how to optimally deploy new sensors in order to improve the coverage of an existing network, (2) how to properly measure the coverage when the path is a line. The best- and worst-case coverage problems that are related to the observability of a path are addressed and formulated into computational geometry problems. We prove that there exists a duality between the two coverage problems, and then solve the two problems together. The presented new-node placement algorithm is shown to deploy new nodes optimally in polynomial time. However, in some applications, such as highway monitoring and anti-missile interception systems, the trajectory of a target is linear but we can not find suitable coverage measurement for the straight-line path in previous research. Therefore, this research presents novel algorithms for coverage measurement of straight-line paths. Based on computational geometry and graph theory, we propose plane sweep algorithms to find the optimal straight-line paths for both the best-case and worst-case coverage problems in polynomial time. Both mathematical analysis and simulations are used to prove the optimality of our algorithms.
360

Advances in ranking and selection: variance estimation and constraints

Healey, Christopher M. 16 July 2010 (has links)
In this thesis, we first show that the performance of ranking and selection (R&S) procedures in steady-state simulations depends highly on the quality of the variance estimates that are used. We study the performance of R&S procedures using three variance estimators --- overlapping area, overlapping Cramer--von Mises, and overlapping modified jackknifed Durbin--Watson estimators --- that show better long-run performance than other estimators previously used in conjunction with R&S procedures for steady-state simulations. We devote additional study to the development of the new overlapping modified jackknifed Durbin--Watson estimator and demonstrate some of its useful properties. Next, we consider the problem of finding the best simulated system under a primary performance measure, while also satisfying stochastic constraints on secondary performance measures, known as constrained ranking and selection. We first present a new framework that allows certain systems to become dormant, halting sampling for those systems as the procedure continues. We also develop general procedures for constrained R&S that guarantee a nominal probability of correct selection, under any number of constraints and correlation across systems. In addition, we address new topics critical to efficiency of the these procedures, namely the allocation of error between feasibility check and selection, the use of common random numbers, and the cost of switching between simulated systems.

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