• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 394
  • 75
  • 49
  • 39
  • 34
  • 29
  • 19
  • 12
  • 8
  • 4
  • 3
  • 3
  • 3
  • 3
  • 2
  • Tagged with
  • 901
  • 140
  • 139
  • 126
  • 79
  • 75
  • 67
  • 64
  • 63
  • 61
  • 59
  • 58
  • 56
  • 54
  • 54
  • 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.
291

An ecological study of Preston Peak's flora : establishing baseline data for climate change research on subalpine vegetation /

O'Donnell, James. January 2003 (has links) (PDF)
Thesis (M.S.)--Southern Oregon University, 2003. / "A thesis submitted to the Department of Biology and the Graduate School of Southern Oregon University in partial fulfillment of the requirements for the degree of Master of Science in Environmental Education." Includes bibliographical references (leaves 93-89). Also available via Internet as PDF file through Southern Oregon Digital Archives: http://soda.sou.edu. Search Bioregion Collection.
292

Participation in large project works management /

Ngan, Hon-wing. January 1985 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1985.
293

Comparisons of acute neuromuscular fatigue and recovery after maximal effort strength training using powerlifts

Theilen, Nicholas Todd 01 January 2013 (has links)
COMPARISONS OF ACUTE NEUROMUSCULAR FATIGUE IN MAXIMAL EFFORT STRENGTH TRAINING USING POWERLIFTS. N. T. Theilen, B. I. Campbell, M. C. Zourdos2, J. M. Oliver3, J. O'Halloran1, N. Asher1, J. M. Wilson4 1University of South Florida, Exercise and Performance Nutrition Laboratory, Tampa, FL 2Florida Atlantic University, Boca Raton, FL 3Texas Christian University, Fort Worth, TX 4University of Tampa, Tampa, FL Neuromuscular fatigue is associated with a decrease in velocity. Following powerlift training, the extent to which fatigue affects the performance velocity of each lift after a specified recovery interval has not yet been investigated. Purpose To assess the level of acute neuromuscular fatigue, as measured by a decrease in peak velocity, as a result of maximal effort strength training sessions with each powerlift. Methods Twelve resistance trained males (22.8 ± 2.6 yrs; 177.1 ± 6.7 cm; 83.0 ± 12.6 kgs) participated in a randomized crossover design with three conditions: Squat (SQ), Bench Press (BP), and Deadlift (DL). Subjects' relative strength included the ability to successfully complete at least 1.5x their bodyweight in the squat exercise. Initially, baseline peak velocity (PV) was measured for each lift at 60% 1RM via a TENDO unit. One training session occurred each Monday for 3 consecutive weeks (1 week for each lift). Each training session consisted of a 1RM of the designated lift followed by 4 sets of 2 repetitions at 92.5% and 4 sets of 3 repetitions at 87.5%. Following training sessions, each lift PV was measured at 24, 48, and 72 hours post-training to compare with baseline measures and determine recovery. Data was analyzed using a repeated measures ANOVA (p<.05). Results SQ: No significant differences in PV of the SQ and DL following SQ training at each time point compared to baseline. Bench press PV significantly declined following squat training (Baseline = 1.069 m/s; 24 hours = 0.974 m/s [p = 0.019]; 48 hours = 1.015 m/s [p = 0.034]; 72 hours = 0.970 m/s [p = 0.004]. BP: No significant differences in PV of the SQ and DL following BP training at each time point compared to baseline. Bench press PV significantly declined only at 24 hours following BP training (Baseline = 1.069 m/s; 24 hours = 0.988 m/s [p = 0.004]). DL: No significant differences in PV of the DL following DL training as compared to baseline. Squat PV significantly declined at 24 hours following the DL training (Baseline = 1.384 m/s; 24 hours = 1.315 m/s [p = 0.032]. Similar to SQ, PV of the BP significantly declined only at 24 hours following DL training (Baseline = 1.069 m/s; 24 hours = 0.979 m/s [p < 0.001]). Conclusions Bench press PV was significantly decreased 24-hours following each of the three powerlifts as compared to baseline values. Interestingly, there were no changes in squat and deadlift PV following training of that specific lift. Practical Applications Regardless of the powerlift trained, bench press PV at 60% was compromised 24-hours later. Therefore, following training of any powerlift, more than 24-hours may be needed to optimize performance in the BP at submaximal intensities.
294

Automatic Macro- and Micro-Facial Expression Spotting and Applications

Shreve, Matthew Adam 01 January 2013 (has links)
Automatically determining the temporal characteristics of facial expressions has extensive application domains such as human-machine interfaces for emotion recognition, face identification, as well as medical analysis. However, many papers in the literature have not addressed the step of determining when such expressions occur. This dissertation is focused on the problem of automatically segmenting macro- and micro-expressions frames (or retrieving the expression intervals) in video sequences, without the need for training a model on a specific subset of such expressions. The proposed method exploits the non-rigid facial motion that occurs during facial expressions by modeling the strain observed during the elastic deformation of facial skin tissue. The method is capable of spotting both macro expressions which are typically associated with emotions such as happiness, sadness, anger, disgust, and surprise, and rapid micro- expressions which are typically, but not always, associated with semi-suppressed macro-expressions. Additionally, we have used this method to automatically retrieve strain maps generated from peak expressions for human identification. This dissertation also contributes a novel 3-D surface strain estimation algorithm using commodity 3-D sensors aligned with an HD camera. We demonstrate the feasibility of the method, as well as the improvements gained when using 3-D, by providing empirical and quantitative comparisons between 2-D and 3-D strain estimations.
295

Characterizing the impacts of air-conditioning systems, filters, and building envelopes on exposures to indoor pollutants and energy consumption in residential and light-commercial buildings

Stephens, Brent Robert 03 July 2012 (has links)
Residential and light-commercial buildings comprise a significant portion of buildings in the United States. They account for a large fraction of the total amount of energy used in the U.S., and they also represent environments where people spend the majority of their time. Thus, the design, construction, and operation of these buildings and their systems greatly affect energy consumption and exposures to airborne pollutants of both indoor and outdoor origin. However, there remains a need to improve knowledge of some key source and removal mechanisms of indoor and outdoor pollutants in residential and light-commercial buildings, as well as their connections to energy use and peak electricity demand. Several standardized field test methods exist for characterizing energy use and indoor air quality in actual buildings, although few explicitly address residential and light-commercial buildings and they are generally limited in scope. Therefore, the work in this dissertation focuses on improving methods to characterize three particular building components for their impacts on exposures to indoor pollutants and their implications for energy consumption: (1) central forced-air heating and cooling (HAC) systems, (2) HAC filters, and (3) building envelopes. Specifically, the research in this dissertation is grouped to fulfill two primary objectives of developing and applying novel methods to: (1) characterize and evaluate central air-conditioning systems and their filters as pollutant removal devices in residential and light-commercial buildings, and to explore their implications for energy consumption, and (2) characterize and evaluate the ability of two particular outdoor pollutants of concern (ozone and particulate matter) to infiltrate indoors through leaks in building envelopes. The research in this dissertation is divided into four primary investigations that fulfill these two objectives. The first investigation (Investigation 1a) addresses Objective 1 by first providing a detailed characterization of a variety of operational characteristics measured in a sample of 17 existing central HAC systems in occupied residential and light-commercial buildings in Austin, Texas, and exploring their implications for exposure to indoor pollutants, energy use, and peak electricity demand. Among the findings in this study, central air-conditioning systems in occupied residential and light-commercial buildings did not operate most of the time, even in the hot and humid climate of Austin, Texas (i.e., ~25% of the time on average in the summer). However, average recirculation rates still make central air-conditioning systems competitive as particle removal mechanisms, given sufficient filtration efficiency. Additionally, this investigation used a larger, much broader, dataset of energy audits performed on nearly 5000 single-family homes in Austin to explore common inefficiencies in the building stock. Residential and light-commercial air-conditioning systems are often inefficient; in fact, residential central air-conditioning systems in particular likely account for nearly 20% of peak electric demand in the City of Austin. As much as 8% of peak demand could be saved by upgrading all single-family homes in Austin to higher-efficiency equipment. The second investigation (Investigation 1b) also addresses Objective 1 by developing and applying a novel test method for measuring the in-situ particle removal efficiency of HAC systems and filters in residential and light-commercial buildings. Results from the novel test method as performed with three test filters and 0.3–10 μm particles in an unoccupied test house agreed reasonably well with results from other field and laboratory test methods. Low-efficiency filters did not increase particle removal much more than simply running the HAC system without a filter, and higher-efficiency filters provided greater than ~50% removal efficiency for most particles greater than 1–2 μm in diameter. The benefit of this test method is that it can be used to measure how filters perform in actual environments, how filter removal efficiency changes with actual dust loading, and how much common HAC design and installation issues, such as low airflow rates, duct leakage, fouled coils, and filter bypass airflow, impact particle removal in real environments. The third investigation (Investigation 2a) addresses Objective 2 by developing and applying a novel test methodology for measuring the penetration of outdoor ozone, a reactive gas, through leaks in exterior building envelopes using a sample of 8 single-family residences in Austin, Texas. These measurements represent the first ever measurements of ozone penetration factors through building envelopes of which I am aware, and penetration factors were lower than the usual assumption of unity (i.e., P = 1) in seven of the eight test homes (ranging from 0.62±0.09 to 1.02±0.15), meaning that some building envelopes provide occupants with more protection from indoor exposures to ozone and ozone reaction byproducts than others. Additionally, ozone penetration factors were correlated with some building characteristics, including the amount of painted wood siding on the exterior envelope and the year of construction, suggesting that simple building details may be used to predict ozone infiltration into homes. Finally, the fourth investigation (Investigation 2b) also addresses Objective 2 by refining and applying a test methodology for measuring the penetration of ambient particulate matter through leaks in building envelopes, and using a sample of 19 single-family residences in Austin, Texas to explore correlations between experimentally-determined particle penetration factors and standardized fan pressurization air leakage tests. Penetration factors of particles 20–1000 nm in diameter ranged from 0.17±0.03 to 0.72±0.08 across 19 homes that relied solely on infiltration for ventilation air. Particle penetration factors were also significantly correlated with results from standardized fan pressurization (i.e., blower door) air leakage tests and the year of construction, suggesting that occupants of older and leakier homes are exposed to more particulate matter of outdoor origin than those in newer tighter homes. Additionally, blower door tests may actually offer some predictive ability of particle penetration factors in single-family homes, which could allow for vast improvements in making easier population exposure estimates. Overall, the work in this dissertation provides new methods and data for assessing the impacts of central air-conditioning systems, filters, and building envelopes on human exposure to indoor pollutants and energy use in residential and light-commercial buildings. Results from these four primary investigations will allow building scientists, modelers, system designers, policymakers, and health scientists to make better informed decisions and assumptions about source and removal mechanisms of indoor pollutants and their impacts on building energy consumption and peak electricity demand. / text
296

Dynamic modeling, optimization, and control of integrated energy systems in a smart grid environment

Cole, Wesley Joseph 30 June 2014 (has links)
This work considers how various integrated energy systems can be managed in order to provide economic or energetic benefits. Energy systems can gain additional degrees of freedom by incorporating some form of energy storage (in this work, thermal energy storage), and the increasing penetration of smart grid technologies provides a wealth of data for both modeling and management. Data used for the system models here come primarily from the Pecan Street Smart Grid Demonstration Project in Austin, Texas, USA. Other data are from the Austin Energy Mueller Energy Center and the University of Texas Hal C. Weaver combined heat and power plant. Systems considered in this work include thermal energy storage, chiller plants, combined heat and power plants, turbine inlet cooling, residential air conditioning, and solar photovoltaics. These systems are modeled and controlled in integrated environments in order to provide system benefits. In a district cooling system with thermal energy storage, combined heat and power, and turbine inlet cooling, model-based optimization strategies are able to reduce peak demand and decrease cooling electricity costs by 79%. Smart grid data are employed to consider a system of 900 residential homes in Austin. In order to make the system model tractable for a model predictive controller, a reduced-order home modeling strategy is developed that maps thermostat set points to air conditioner electricity consumption. When the model predictive controller is developed for the system, the system is able to reduce total peak demand by 9%. Further work with the model of 900 residential homes presents a modified dual formulation for determining the optimal prices that produce a desired result in the residential homes. By using the modified dual formulation, it is found that the optimal pricing strategy for peak demand reduction is a critical peak pricing rate structure, and that those prices can be used in place of centralized control strategies to achieve peak reduction goals. / text
297

Knowing the Neighbours: Post-Growth Umeå

Taylor, Joshua January 2015 (has links)
This thesis is about researching methods/testing approaches to inhabiting/existing in a post-growth Norrland, the collective term for Sweden’s most northerly counties. With neo-liberal capitalism lurching from crisis to crisis, modernity, progress and the state are in trouble. Small shops close, iconic buildings are constructed, agriculture, the most vital of industries, is collapsing and competition is the watchword. If peak-oil, the consumer culture and individualism combine to lead us into a dystopian slough, what is the alternative? This work aims to investigate and show the existing conditions that are producing the current state of affairs in Norrland, with emphasis on Röbäck, one of Umeå’s agricultural satellites cum dormitory suburbs. This research will provide the necessities for dreamed proposals about a possible post-growth future, integrating alternative views of technology and modes of living with the ethos of the common and our use of shared resources.
298

Uniaxial tensile testing technique to obtain softening response of ultra-high performance concrete under confining pressures

Reichard, Brett David 21 September 2015 (has links)
The focus of this thesis is to research and develop a uniaxial tensile testing technique and methodology to attain the post-peak softening response for ultra-high performance concrete under confining pressure. This particular multi-axial behavior is valuable in improving current material models in finite element simulations for US Army applications into hardened target structures.
299

Power estimation of microprocessors

Sambamurthy, Sriram 13 December 2010 (has links)
The widespread use of microprocessor chips in high performance applications like graphics simulators and low power applications like mobile phones, laptops, medical applications etc. has made power estimation an important step in the manufacture of VLSI chips. It has become necessary to estimate the power consumption not only after the circuits have been laid out, but also during the design of the modules of the microprocessor at higher levels of design abstraction. The design of a microprocessor is complex and is performed at multiple layers of abstraction before it finally gets manufactured. The processor is first conceptually designed using blocks at the system level, and then modeled using a high-level language (C, C++, SystemC). This enables the early development of software applications using these high-level models. The C/C++ model is then translated to a hardware description language (HDL), that typically corresponds to the register transfer level (RT-Level). Once the processor is defined at the RT-Level, it is synthesized into gates and state elements based on user-defined constraints. In this thesis, novel techniques to estimate the power consumed by the microprocessor circuits at the gate level and RT-level of abstraction are presented. At the gate level, the average power consumed by microprocessor circuits is straight-forward to estimate, as the implementation is known. However, estimating the maximum or peak instantaneous power consumed by the microprocessor as a whole, when it is executing instructions, is a hard problem due to the high complexity of the state space involved. An hierarchical approach to estimate the peak power using powerful search techniques and formal tools is presented in this thesis. This approach has been extended and applied to solve the problem of estimating the maximum supply drop. Details on this extension and a discussion of promising results are also presented. In addition, this approach has been applied to explore the possibility of minimizing the leakage component of power dissipation, when the processor is idle. At the register transfer level, estimating the average power consumed by the circuits of the microprocessor is by itself a challenging problem. This is due to the fact that their implementation is unknown at this level of abstraction. The average power consumption directly depends on the implementation. The implementation, in turn, depends on the performance constraint imposed on the microprocessor. One of the factors affecting the performance of the microprocessor, is the speed of operation of its circuits. Considering these factors and dependencies (for making early design decisions at the RT-Level), a methodology that estimates the power vs. delay curves of microprocessor circuits has been developed. This will enable designers to make design decisions for even rudimentary designs without going through the time consuming process of synthesis. / text
300

The influence and controls of climate and geology on landforms: with special reference to the Castle Peakdistrict.

Woo, Ming-Ko., 胡鳴高. January 1967 (has links)
published_or_final_version / Geography and Geology / Master / Master of Arts

Page generated in 0.2148 seconds