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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.
131

The Development of Two Units for <em>Basic Training and Resources for Teaching English to Speakers of Other Languages</em>: "Working Successfully with Young Learners" and "Working Successfully with Very Young Learners"

Healy, Heidi 26 June 2012 (has links) (PDF)
Many thousands of people with varying degrees of preparation teach English as a second or foreign language to many millions of people around the world. Some of these teachers are novice, volunteer teachers, who have not received any professional-level training. These novice teachers help to meet the demand for English teachers by often teaching for little remuneration or in non-ideal teaching conditions. These teachers can benefit from receiving training in how to teach English as a foreign language. Basic Training and Resources for Teaching English to Speakers of Other Languages (BTRTESOL) is a program that is being created to provide training to these novice teachers on a wide variety of topics, including teaching various age groups. Research has shown that children learn language differently from adults. It is therefore important that teachers be aware of the cognitive, social, and emotional development of children and the teaching techniques that help children acquire language. Additionally, important differences exist between very young children (aged 3-7) and children (aged 7-11) that affect how they learn and how they should be taught. In addition to novice, untrained teachers, people who have been trained to teach English to adults may work abroad teaching English to children. They can benefit from additional training in educating children. In sum, training in the distinctive language learning needs of children will help all these teachers and their students to be more successful.
132

VLSI NMOS hardware design of a linear phase FIR low pass digital filter

Chabbi, Charef January 1985 (has links)
No description available.
133

Parallel processing and VLSI design: A high speed efficient multiplier

Dandu, Venkata Satyanarayana Raju January 1985 (has links)
No description available.
134

Molecular Epidemiology and Pathogenicity of the Very Virulent Infectious Bursal Disease Pathotype in United States Poultry

Stoute, Simone Tricia 24 August 2012 (has links)
No description available.
135

Using N.2 to Model a Microprocessor System

Patz, Benjamin J. 01 January 1985 (has links) (PDF)
Due to the complexity of designing digital systems using VLSI parts, a tool for aiding in system level design specification and verification is needed. Functional level modeling languages and simulators provide that tool. An example of such a tool is the N.2 package of software produced by Endot Inc. and soon to be running on a VAX computer at the University of Central Florida. An overview of the N.2 system is presented in this paper with emphasis on the modeling language of N.2, ISP’. A Small Instruction set Computer (SIC), originally specified in HAPL, is designed with this software using several design methodologies. These range from an instruction level implementation to a microcoded register level implementation. The ISP’ source code is provided for each implementation. Comments on the ability of the N.2 software to model systems at various levels of design abstraction are made. A comparison of the functional modeling language of N.2, ISP’ to other functional level design languages is made. Finally, some areas that warrant further investigation are presented.
136

An Investigation of Fundamental Frequency Limitations for HF/VHF Power Conversion

Xiao, Chucheng 13 October 2006 (has links)
The volume reduction in power converters over the past several decades can chiefly be attributed to increases in switching frequency. It is to be expected that the trends towards miniaturization will maintain steady pressure to keep this pace of increasing switching frequencies of power converters. However certain fundamental limits in high frequency power conversion are being reached as frequencies are being pushed deeper into the megahertz range, inhibiting substantial further increases. The work reported in this dissertation is intended to systematically investigate the fundamental frequency limitations, identify some of the solutions for HF/VHF power conversion and to provide guidelines and tools to optimize the performance of power converters by maximizing frequency. A number of multi-megahertz power converters are examined to evaluate the present status and future trend of HF/VHF power conversion. An interesting trend between power level and frequency is observed. A general limitation about the power level and frequency, independent of design details, is derived from the physics of the semiconductor devices, which determines the upper bound of the power levels as frequency increases. A 250 MHz DC-DC power converter (derived from the Class E power amplifier) is analyzed and demonstrated with discrete components, which again verifies the trend between power level and frequency. The power losses in the semiconductor devices are discussed, and optimization criteria for minimizing the power losses of the devices, are discussed. By relating the power losses to the semiconductor materials' properties, a methodology for selecting proper materials is identified for high frequency and high efficiency power conversion. The frequency scaling effects of passive components, still dominating the volume of the modern power converter, is analyzed. A generic multi-disciplinary methodology is developed to analyze and maximize frequency and performance of passive components in terms of power density and efficiency. It is demonstrated how the optimum frequency can be identified, and how power conversion efficiency deteriorates beyond this optimum under a fixed maximum temperature. Power loss measurement is becoming more challenging as higher frequency and higher efficiency power conversion. To achieve an accurate power loss measurement in a high frequency, high efficiency power electronics system or component, limitations of electrical measurement are identified, and various calorimetric methods are surveyed. Calorimetric methods are more accurate due to the direct heat loss measurement. An advanced calorimetric system is proposed, analyzed, and tested, demonstrating about 5% error in total losses up to 25W. / Ph. D.
137

New Way of Generating Electromagnetic Waves Using Permanent Magnet

Hosseini Fahraji, Ali 01 February 2022 (has links)
The ever-increasing demand for wireless communication has led to an incentive to increase the data rate and reduce the size of communication devices, be it antennas or other components of RF front-ends. The emphasis is primarily on increasing data rate, which leads to the use of higher frequency bands and wider bandwidths in modern communication technology research and innovations. However, increasing frequency in many technology areas cannot necessarily be beneficial because of physical constraints. For example, communication under seawater or other RF harsh environment requires very-low-frequency (VLF) or ultra-low-frequency (ULF) signals to penetrate lossy media that block high-frequency signals. Furthermore, recent advances in neuroscience have demonstrated the potential of VLF and ULF electromagnetic (EM) waves for studying brain function and treating neurological conditions. The main challenge is that most VLF and ULF generators are large and power-hungry, making them impractical to use in many applications. As a result, recent approaches using permanent magnets have started to provide groundbreaking solutions that can revolutionize VLF/ULF communication. This work presents a new method for generating low-frequency EM waves for navigation and communication in challenging environments, such as underwater and underground, as well as magnetic stimulation of brain neurons. The key concept is to disturb the magnetic energy stored around a permanent magnet in a time-variant fashion. The magnetic reluctance of the medium around the permanent magnet is modulated to alter the magnetic flux intensity and direction (disturb the stored energy) in order to achieve this goal. The nonlinear properties of the surrounding magnetic material are a critical phenomenon for efficient and effective modulation. Since the proposed method of generating the EM field is not based on a second-order system (resonant structure), the bandwidth of any modulation schema is not limited to the overall system quality factor. A transmitter is prototyped as a proof of concept, and the generated field is measured. Compared to the rotating magnet, the prototyped transmitter can modulate up to 50% of the permanent magnet's stored energy with much lower power consumption. The magnetic equivalent circuit (MEC) approach is also used to analyze the transmitter. Finally, the transmitter is optimized, and the measurement results show a 7 dB improvement in efficiency compared to the primary structure. As a result of promising performance, we propose that this method be used to improve the performance of transcranial magnetic stimulation (TMS) devices. Furthermore, the comparison simulated results back up the validity of the proposed technique, revealing that focality and penetration depth are improved while utilizing much less power than traditional TMS devices. / Doctor of Philosophy / The growing demand for wireless communication has created an incentive to increase the data rate while decreasing the size of communication devices, whether they are antennas or other radio frequency (RF) components between the antenna and at least one mixing stage of a receiver and/or the power amplifier of the transmitter. The emphasis is primarily on increasing data rate, which leads to the use of higher frequency bands and wider bandwidths in modern communication technology research and innovations. However, increasing frequency in many technology areas may not be beneficial because of physical constraints. For example, communication under seawater or underground requires very-low-frequency (VLF) or ultra-low-frequency (ULF) signals to penetrate lossy media that block high-frequency signals. Furthermore, recent advances in neuroscience have demonstrated the potential of VLF and ULF electromagnetic (EM) waves for studying brain function and treating neurological conditions. The main challenge is that most VLF and ULF generators are large and power-hungry, making them unsuitable for many applications. As a result, recent approaches using permanent magnets have started to provide groundbreaking solutions that can revolutionize VLF/ULF communication. This work presents a new method for generating low-frequency EM waves for navigation and communication in challenging environments, such as underwater and underground, as well as magnetic stimulation of brain neurons. The key idea is to disturb the magnetic energy stored around a permanent magnet in a time-variant fashion. The magnetic reluctance of the medium around the permanent magnet is modulated to change the magnetic flux intensity and direction (disturb the stored energy) in order to achieve this goal. The nonlinear properties of the surrounding magnetic material are a critical factor in achieving efficient and effective modulation. Since the proposed method of generating the EM field does not rely on a second-order system (resonant structure), the bandwidth of any modulation schema is not constrained by the overall system quality factor. As a proof of concept, a transmitter is prototyped, and the generated field is measured. Compared to the rotating magnet, the prototyped transmitter can modulate up to 50% of the permanent magnet's stored energy with much lower power consumption. The magnetic equivalent circuit (MEC) approach is also used to analyze the transmitter. Finally, the transmitter is optimized, and the measurement results show a 7 dB improvement in efficiency compared to the primary structure. As a result of promising performance, we propose that this method be used to improve the performance of transcranial magnetic stimulation (TMS) devices. Furthermore, the comparison simulated results support the validity of the proposed technique, revealing that focality and penetration depth are improved while using much less power than traditional TMS devices.
138

A distributed design rule checker for VLSI layouts

Al-Mahmood, Saiyid Jami Islah Ahmad 01 November 2008 (has links)
VLSI technology is continually fueling the need for more efficient computer aided design tools. Parallel or distributed processing is a possible solution to this problem. Advances in computer networking have made distributed processing over a local area network very attractive and cost-effective. This research investigates the application of such a large-grained parallel processing method to the task of checking geometric constraints or design rules that are imposed on the layout of VLSI circuits to ensure a correct implementation of the design despite imperfections in the fabrication process. The thesis begins with a study of design rule checking algorithms including algorithms for parallel processing as applied to design rule checking. Then, the algorithms for a technology independent design rule verification tool are developed. For distributed processing, two separate approaches are examined. One approach, called the data partitioning method, divides a fully instantiated or non-hierarchical layout into several sections and then processes each section on a different computer. The second approach looks for smaller tasks within the design rule checking process that can be executed in parallel and is called the task partitioning method. A dynamic task-scheduling algorithm is used to assign the tasks to the available processors. Implementations of both of these parallel processing schemes on a local area network of workstations are described. Experiments are performed to assess the performance of the programs and the results of testing a few layouts are presented. / Master of Science
139

Analytical modeling and simulation of bicmos for VLSI circuits

Narayanan, Prakash 25 April 2009 (has links)
Interest in BiCMOS technology has been generated recently due to the potential advantages this technology offers over conventional CMOS which enjoys widespread use in today’s semiconductor industry. However, before BiCMOS can be readily adopted by the VLSI community, an understanding of the design issues and tradeoffs involved when utilizing it, must be achieved. The principal focus of this research is to move towards such an understanding through the means of analytical modeling and circuit simulation using PSPICE [1]. The device chosen for the modeling approach is the basic BiCMOS Inverting Buffer Driver. The model yields equations that characterize output rise and fall transients and quantify the delays incurred therein. At the end of the analysis, we have a composite set of delay equations that are a measure of the total gate delay and reflect the importance of individual device and circuit parameters in determining this delay. Further investigations conducted to determine the influence of device, circuit and process parameters on BiCMOS, indicate that this technology is far more resilient to variations in such parameters than CMOS. At the end of this research, we are able to make a definitive judgement about BiCMOS performance and its superiority over CMOS in the switching speed domain. / Master of Science
140

Preoperative Weight Loss for Patients with Obesity Prior to Non-Bariatric Surgery / PREOPERATIVE WEIGHT LOSS FOR NON-BARIATRIC SURGERY

McKechnie, Tyler January 2023 (has links)
Preoperative optimization of patients with obesity prior to non-bariatric surgery through weight loss interventions may significantly improve perioperative outcomes and decrease healthcare resource utilization associated with this increasingly prevalent patient population. Ultimately, very low energy diets and bariatric surgery have the potential to become a cornerstone of pre-habilitation protocols for patients with obesity undergoing elective operations for both benign and malignant disease processes. Further adequately powered prospective study is warranted. / Background: Improved preoperative weight loss strategies for patients with obesity undergoing major non-bariatric surgery are necessary. As such, this research program focusing on evaluating different preoperative weight loss interventions, namely very low energy diets (VLEDs) and bariatric surgery, for patients with obesity undergoing major non-bariatric surgery was developed. Methods: The first chapter is a systematic review evaluating the use of preoperative VLEDs reported according to PRISMA. Medline, EMBASE, CENTRAL, and PubMed were systematically searched from inception through to July 2021. Articles were included if they evaluated VLED utilization prior to non-bariatric surgery. Pairwise meta-analyses using inverse variance random effects were performed. The second chapter is a retrospective study investigating the impact of a history of bariatric surgery on patients undergoing surgery for colorectal cancer. Adult patients undergoing resection for colorectal cancer from 2015-2019 were identified from the National Inpatient Sample (NIS). Patients were stratified according to their history of bariatric surgery. Propensity score matching with 4:1 nearest-neighbor matching was performed. Results: In Chapter 1, 13 studies with 395 patients with obesity receiving VLEDs preoperatively in preparation for non-bariatric surgery were included. Adherence with VLEDs ranged from 94- 100%. Mean preoperative weight loss ranged from 3.2-19.2kg. Patients using VLEDs had decreased intraoperative blood loss (MD 305.20mL, 95%CI 208.18-402.23, p<0.00001). In Chapter 2, 1,197 patients without prior bariatric surgery and 376 patients with prior bariatric surgery were included. Patients with prior bariatric surgery had an absolute reduction of 6.5% in overall in-hospital postoperative morbidity (19.1% vs. 25.6%, p<0.0001) and a $5,256 decrease in hospitalization cost ($70,344 vs. $75,600, p=0.034). iv Conclusion: These studies support the use of preoperative weight loss techniques for patients with obesity prior to non-bariatric surgery. VLEDs and bariatric surgery have the potential to become cornerstones of pre-habilitation protocols for patients with obesity undergoing elective operations. Further adequately powered prospective study is warranted. / Thesis / Master of Science (MSc) / Preoperative weight loss strategies for patients with obesity undergoing major non- bariatric surgery are becoming a necessity given the ubiquitous nature of obesity in our current surgical patient population. The first chapter is a systematic review and meta-analysis evaluating the use of preoperative very low energy diets (VLEDs) prior to non-bariatric surgery for patients with obesity. After screening nearly 800 citations and including 13 studies, this review identified that while currently available evidence is heterogenous, preoperative VLEDs are safe, well tolerated, and effectively induce preoperative weight loss in patients with obesity undergoing non-bariatric surgery for both benign and malignant disease. The second chapter is a population- level retrospective study investigating the impact of a history of bariatric surgery for weight loss on patients undergoing surgery for colorectal cancer. The findings from this study suggested that bariatric surgery prior to surgery for colorectal cancer may be associated with decreased postoperative morbidity and healthcare resource utilization.

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