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Non-Negative Least Square Optimization Model for Industrial Peak Load EstimationModa, Hari Priya 05 January 2010 (has links)
Load research is the study of load characteristics on a power distribution system which helps planning engineer make decisions about equipment ratings and future expansion decisions. As it is expensive to collect and maintain data across the entire system, data is collected only for a sample of customers, where the sample is divided into groups based upon the customer class. These sample measurements are used to calculate the load research factors like kWHr-to-peak kW conversion factors, diversity factors and 24 hour average consumption as a function of class, month and day type. These factors are applied to the commonly available monthly billing kW data to estimate load on the system.
Among various customers on a power system, industrial customers form an important group for study as their annual kWHr consumption is among the highest. Also the errors with which the estimates are calculated are also highest for this class. Hence we choose the industrial class to demonstrate the Lawson-Hanson Non-Negative Least Square (NNLS) optimization technique to minimize the residual squared error between the estimated loads and the SCADA currents on the system. Five feeders with industrial dominant customers are chosen to demonstrate the improvement provided by the NNLS model. The results showed significant improvement over the Nonlinear Load Research Estimation (NLRE) method. / Master of Science
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Effect of Brief Intense Stair Climbing on Cardiometabolic Health / Brief Intense Stair Climbing and Cardiorespiratory FitnessAllison, Mary K January 2016 (has links)
A thesis submitted to the School of Graduate Studies in partial fulfillment of the requirements for the degree Master of Science. / Sprint interval training (SIT) is a time-efficient strategy to improve cardiorespiratory fitness; however, most protocols have been studied in a laboratory setting and require specialized equipment. We investigated the efficacy of brief intense stair climbing as a practical model of SIT to improve cardiometabolic health, with a key measure being cardiorespiratory fitness as indicated by peak oxygen uptake (VO2peak). Two separate studies, each consisting of an acute and chronic phase, were conducted in a total of 31 sedentary women (age=24±10 y; BMI=23±4 kg•m-2). The acute phase of Study 1 established that the heart rate (HR), blood lactate concentration (BLa), and rating of perceived exertion (RPE) responses were similar when participants (n=8) performed a SIT protocol that involved 3x20-s “all-out” efforts of either continuous stair climbing or cycling, interspersed with 2 min of recovery. The chronic phase demonstrated that when participants (n=12) performed the 3x20-s stair climbing protocol 3 d•wk-1 for 6 wk, absolute and relative VO2peak increased by 12%, or ~1 metabolic equivalent (1.80±0.25 to 2.02±0.27 L•min-1, p<0.001), as there were no changes in body mass (p=0.35), fat free mass (FFM; p=0.09) or % body fat (p=0.42). There were also no changes in resting systolic and diastolic blood pressure (BP; p=0.82 and p=0.97, respectively), resting HR (p=0.62), and fasting insulin sensitivity (p=0.52). The acute phase of Study 2 established that the HR and RPE responses were similar when participants (n=11) performed three different stair climbing protocols. The protocols investigated include the 3x20-s continuous ascent model used in Study 1 (protocol 1), as well as 3x60-s bouts of ascending and descending either one or two flights of stairs, with 60-s of recovery (protocol 2 and 3, respectively). The chronic phase demonstrated that when the same group of subjects performed the 3x60-s 1-flight protocol 3 d•wk-1 for 6 wk, absolute and relative VO2peak increased by 8 and 7%, respectively (1.79±0.36 to 1.93±0.39 L•min-1, p=0.001; 31.2±4.6 to 33.3±5.3 mL•kg-1•min-1; p=0.01). Despite no changes in % body fat (p=0.10), there was an increase 3% increase in FFM (p<0.001). There was no change in systolic (p=0.50) and diastolic BP (p=1.00), but resting HR improved by 8% after training (p=0.03). The change in insulin sensitivity derived from an OGTT was 7.1±11 mg I2•mmol-1•mIU-1•min-1 (p=0.056). These findings demonstrate that brief intense stair climbing is a practical, time-efficient strategy to improve cardiorespiratory fitness in previously untrained women. / Thesis / Master of Science (MSc) / Sprint interval training (SIT), involving brief bouts of very intense exercise
separated by short periods of recovery, is a time-efficient alternative to traditional
endurance training for improving fitness. This has largely been established in laboratory settings using specialized equipment, which is impractical for many individuals. This project examined whether brief intense stair climbing was a practical model of SIT to elicit adaptations previously shown with cycling protocols. Subjects performed either three 20-s ascents interspersed with 2 min recovery periods, or three 60-s bouts of ascending and descending one or two flights of stairs, with 60-s recovery periods. Both protocols were 10 min in duration including warm-up and cool-down, and subjects trained three days per week for six weeks. The main finding was that stair climbing is a practical, time-efficient model to improve fitness in previously sedentary individuals.
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Distributing the Grid: Transactive Integration of Energy ResourcesRaker, David M. 11 July 2022 (has links)
No description available.
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The Role of National Energy Policy in Mitigating Peak OilSmart, Anne 27 April 2007 (has links)
No description available.
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Effect of Music Genre on Power Output during a Wingate TestCochran, Taylor January 2014 (has links)
No description available.
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The Effect of Normobaric Hypoxia on Power Output During Multiple Wingate Anaerobic TestsNielsen, Corey Michael 05 May 2017 (has links)
No description available.
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Geospatial Patterns in Vulnerability to Peak OilShender, Benjamin L. 05 August 2010 (has links)
No description available.
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The effects of peak load demand and energy charges on the industrial use of electricity /Schwarz, Peter M. January 1980 (has links)
No description available.
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EVALUATION OF SNOWMELT ESTIMATION TECHNIQUES FOR ENHANCED SPRING PEAK FLOW PREDICTIONAGNIHOTRI, JETAL January 2018 (has links)
In cold and snowy countries, water resources management and planning require accurate and reliable spring peak flow forecasts which call for adequate snowmelt estimation techniques. Thus, exploring the potential of snowmelt models to improve the spring peak flow prediction has been an active research area. Snow models vary in degree of complexity from simple empirical models to complex physically based models. Whereas majority of studies on snowmelt modeling have focused on comparing the performance of empirical snowmelt estimation techniques with physically based methods, very few studies have investigated empirical methods and conceptual models for hydrological applications. This study investigates the potential of a simple Degree-Day Method (DDM) to effectively and accurately predict peak flows compared to sophisticated SNOW-17 model at La-Grande River Basin (LGRB), Quebec and Upper Assiniboine river at Shellmouth Reservoir (UASR), Manitoba. Moreover, since hydrologic models highly rely on estimated parameter vectors to produce accurate streamflow simulations, accurate and efficient parameter optimization techniques are essential. The study also investigates the benefits of seasonal model calibration versus annual model calibration approach. The study is performed using two hydrological models, namely MAC-HBV (McMaster University Hydrologiska Byrans Vattenbalansavdelning) and SAC-SMA (Sacramento Soil Moisture Accounting) and their model combinations thereof.
Results indicate that the simple DDM performed consistently better at both study sites and showed significant improvement in prediction accuracy at UASR. Moreover, seasonal model calibration appears to be an effective and efficient alternative to annually calibrated model especially when extreme events are of particular interest. Furthermore, results suggest that SAC-SMA model outperformed MAC-HBV model, no matter what snowmelt computation method, calibration approach or study basin is used. Conclusively, DDM and seasonal model optimization approach coupled with SAC-SMA hydrologic model appears to be a robust model combination for enhanced spring peak flow prediction. A significant advantage of aforementioned modeling approach for operational hydrology is that it demonstrates computational efficiency, ease of implementation and is less time-consuming. / Thesis / Master of Science (MSc)
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Large Eddy Simulation and Wavelet Analysis of the Flow Field around a Surface Mounted PrismElsayed, Mohamed Aly Khamis 27 May 2005 (has links)
Unsteady large-scale vortices, formed by the roll-up of free shear layers separating along sharp edges, are the dominant flow characteristics of the turbulent flow over buildings. These vortical structures interact with each other and with the building surface resulting in secondary separation and severe pressure fluctuations. Moreover, the interaction of the large-scale vortices with the multiplicity of turbulence scales in the incoming wind exacerbates their unsteady motion and hence significantly affects the pressure fluctuations spectra experienced by the building.
Large-eddy simulations are conducted to study the interaction of homogeneous turbulence in the incident flow with a surface-mounted prism. A compact fifth-order upwind difference scheme is used to effectively and accurately perform the simulations. Three cases of incident flow are considered. In one case, the prism is placed in a smooth uniform flow. In the second case, homogeneous isotropic turbulence with von Karman spectrum is superimposed on the uniform flow at the inflow boundary. The integral length scale is one-half the prism height. In the third case, the integral length scale is equal to the prism height.
The numerical results are compared with experimental measurements reported by Tieleman et al. (2002). The results show that the highest negative mean value of the pressure coefficient on the roof and the sides is about 30% larger in case two of turbulent inflow and takes place closer to the windward edge of the prism. Moreover, the pressure coefficients on the roof and sides of the prism in the case of turbulent inflow show a higher level of variations in comparison with the case of smooth inflow conditions. The predicted mean characteristics of the pressure coefficients in the turbulent case match the experimental values in terms of both magnitude and location on the roof of the prism reported in Tieleman et al. (1998) and Tieleman et al. (2002). As for the peak value, the peak value of -2 obtained in the turbulent inflow case two is about 20% smaller than the values measured experimentally by Tieleman et al. (2002). On the other hand, it is stressed that the peak value in the simulations would increase as the duration of the simulation is increased to match that of the experimental measurement. The results also show that the turbulent case yields a non-exceedence probability for the peak pressure coefficient that is closer to the one obtained from the measured data than the smooth case data.
Also, spectral and cross-spectral analysis are carried out using complex Morlet wavelet transform to investigate pressure-velocity relation. The study shows that the nonlinearity in the relationship of velocity-pressure is detected using wavelet bicoherence. / Ph. D.
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