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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.
391

The use of different nutritional strategies and mathematical models to improve production efficiency, profitability, and carcass quality of feedlot cattle

de Vasconcelos, Judson Tadeu 25 April 2007 (has links)
Forty eight crossbred steers (BW = 296 ± 16.7 kg) were fed four dietary treatments for 56 d: AL-LS (low starch diet fed ad libitum for a rate of gain of 1 kg/d), AL-HS (high starch diet fed ad libitum), LF-HS (a limit fed high starch diet designed to be isocaloric with AL-LS), and AL-IS (a diet fed ad libitum for the midpoint daily energy intake between AL-LS and AL-HS). On d 57 all steers were placed on AL-HS for finishing until d 140. Steers that consumed more total energy (AL-HS and AL-IS) throughout production achieved greater carcass fatness in the end of the 140 d period, although these responses were difficult to evaluate via real-time ultrasound measurements. No differences in insulin and glucose kinetics were observed. Data suggested that energy source may influence energy partitioning during the growing period, but these effects may be overcome by differences in energy intake. Higher marbling scores (AL-HS and AL-IS) rewarded higher grid values and greater premiums, which increased profitability. This data set was also used for a model evaluation that showed that mathematical models (CVDS and NRC) were able to explain most of the variation in individual feed requirements of group- fed growing and finishing cattle. Another data set was used for evaluation of a decision support system Cornell Net Carbohydrate and Protein System (CNCPS) as a tool to minimize nutrient excretion from fed cattle. One-hundred eight-four group- fed steers were fed a 13% crude protein (CP) diet until reaching 567 kg of BW, when their diets were either maintained at 13% or reduced to 11.5% or 10% CP. Data from the second half of the experiment were modeled to predict urinary, fecal, and total N excretion. As dietary CP decreased from 13 to 11.5%, the model indicated a total N excretion of 16%. An even greater reduction in total N excretion (26%) occurred when dietary CP was decreased from 11.5% to 10%. The overall decrease from 13 to 10% CP resulted in a reduction of total N excretion by 38%. Data suggest that decision support sys tems can be used to assist in balancing diets to meet environment restriction.
392

A scripting interface for doubly linked face list based polygonal meshes

Tett, Stuart Tosten 10 October 2008 (has links)
This thesis presents a scripting language interface for modeling manifold meshes represented by a Doubly Linked Face List (DLFL).With a scripting language users can create procedurally generated meshes that would otherwise be tedious or impractical to create with a graphical user interface. I have implemented a scripting language interface for the user to create stand-alone scripts as well as script interactively within a graphical environment.
393

Why the weak win wars a study of the factors that drive strategy in asymmetric conflict /

Hartigan, Jake. January 2009 (has links) (PDF)
Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Rothstein, Hy. Second Reader: Blanken, Leo. "December 2009." Description based on title screen as viewed on January 26, 2010. Author(s) subject terms: Strategy, asymmetric warfare, unconventional warfare, Arreguin-Toft, probability of victory, institutional predisposition, Afghanistan. Includes bibliographical references (p. 77-82). Also available in print.
394

Sensor interceptor operational policy optimization for maritime interdiction missions

Rozen, Nir. January 2009 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Royset, Johannnes O. Second Reader: Kress, Moshe. "December 2009." Description based on title screen as viewed on January 29, 2010. Author(s) subject terms: Stochastic model, dynamic programming , stochastic optimization, Maritime Interdiction Missions, MIM, Maritime Interdiction Operations, MIO. Includes bibliographical references (p. 61). Also available in print.
395

A theory and model for the planning of land combat

Schwartz, Thomas Joseph. January 1990 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Caldwell, William J. ; Johnson, Laura D. Second Reader: Whitaker, Lyn R. "September 1990." Description based on title screen as viewed on December 18, 2009. DTIC Descriptor(s): Test And Evaluation, Data Bases, Warfare, Land Warfare, Maximum Likelihood Estimation, Theory, Coherence, Planning, War Games, Battles, Corps Level Organizations. DTIC Identifier(s): Army Operations, War Games, Land Combat Operations, Theses, Army Planning, Data Bases, Mathematical Models. Author(s) subject terms: Land warfare, military planning, military science, theory of combat, categorical modeling, multivariate analysis. Includes bibliographical references (p. 52-53). Also available in print.
396

Accounting for non-stationarity via hyper-dimensional translation of the domain in geostatistical modeling

Cuba Espinoza, Miguel Angel. January 2009 (has links)
Thesis (M. Sc.)--University of Alberta, 2009. / Title from PDF file main screen (viewed on Feb. 19, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Mining Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.
397

Environmental Assessment of a Residential Building According to Miljöbyggnad

Li, Ning January 2015 (has links)
Miljöbyggnad is a Swedish system for certifying building in regarding to energy, indoor climate and materials. Energy usage in built environment occupies more than a third of total energy consumption and greenhouse gas emissions in Sweden (SEA, 2008). Among fifteen indicators regulated by Miljöbyggnad, four indicators which consist of specific energy use, thermal climate winter, thermal climate summer and daylight have been analyzed in this report. There has two objectives for the project. The first objective is to make optimized approaches for the building according to baseline simulation model. And the second objective is to make assessment of the optimized model based on Miljöbyggnad environmental certification. As a conclusion, the implemented approaches helped to improve indoor thermal comfort and decrease demand of operational electricity for lighting. The four analyzed indicator of the optimized model have achieved GOLD level according to criteria regulated by Miljöbyggnad.
398

Wireless scheduling with limited information

Gopalan, Aditya 31 January 2012 (has links)
This thesis examines the problem of scheduling with incomplete and/or local information in wireless systems. With large numbers of users and limited feedback resources, wireless systems require good scheduling algorithms to attain their performance limits. Classical studies on wireless scheduling investigate in much detail settings where the full state of the system is available when scheduling users. In contrast, this thesis focuses on the case where valuable network state information is lacking at the scheduler, and studies its resulting effect on system performance. The insights gained from the analysis are used to develop efficient wireless scheduling algorithms that operate with limited state information, and that guarantee high throughput and delay performance. The first part of the thesis considers scheduling for stability in a wireless downlink system, where a base station or server schedules transmissions to users, while acquiring channel state information from only subsets of users. It is shown that the system’s throughput region is completely characterized by the marginal channel statistics over observable channel subsets. Effective, queue-length based joint sampling and scheduling algorithms are developed that observe appropriate subsets of channels and schedule users, and the algorithms are shown to be optimal in the sense of throughput. Next, the thesis studies the queue-length performance of wireless scheduling algorithms that use only partial, subset-based channel state information. The chief objective here is to design partial information-based scheduling algorithms that keep the packet queues in the system short, and in this regard, the contributions of this thesis are twofold. First, from the algorithmic perspective, wireless scheduling algorithms using partial channel state information are designed that minimize the likelihood of queue overflow, in a suitable sense, across all partial information scheduling algorithms. The second key contribution is technical, by the development of novel analytical techniques to study the stochastic dynamics of partial state information-based algorithms. These techniques are not only instrumental in showing the optimality results above, but are also of independent interest in understanding the behavior of algorithms which rely on partially sampled system state. The second part of the thesis investigates coordinated inter-cell wireless scheduling across multiple base stations, each possessing only local and partial channel state information for its own users. Coordinated scheduling is necessary to mitigate interference between users in adjacent cells, but information sharing between the base stations is limited by high latencies in the backhauls that interconnect them. A class of distributed scheduling algorithms is developed in which the base stations share only delayed queue length information with each other, and locally acquire partial channel state information, to schedule users. These algorithms are shown to be throughput-optimal, and their average backlog performance in terms of the inter-base station latency is quantified. / text
399

The effect of noise on the dynamics of a 2-D walking model

Campbell, Bradley Cortez 27 February 2012 (has links)
Walking models have been used to explore concepts such as energy, step variability, control strategies and redundancy in walking. A 2-D dynamic walking model was used to determine the levels of variability in gait while being perturbed. The perturbations were added in the form of randomly added noise applied at different magnitudes. The model was comprised of two equal length legs and masses at the feet and hips. The model walked on a flat surface and each step was initialed by an impulse at the swing leg. The magnitude of the impulse determined the size of the model's steps. In this study, the walker took steps with lengths that were than were analogous to humans. An attempt to offset the effect of the noise was made by adding a proportional controller to correct the errors of the applied impulse. The control equation was comprised of gain, A, and noise, [xi], term. The step length, time and speed were calculated to analyze how the model walks. It was hypothesized that the model would use a strategy similar to humans on a treadmill and follow a goal equivalent manifold. The manifold was all possible solutions of step length and step time for maintaining constant speed. Any fluctuations in step length and time would still result in constant speed. The results showed that the model's gait became more variable as noise was added. When the control was added through the gain being increased, the model steps became more variable. The model did not follow the same control strategy as humans and coordinate steps along the GEM. As the model began taking longer step lengths the step time decreased. / text
400

From outcrop to functional reservoir model : using outcrop data to model the tidally dominated esdolomada sandstone, NE Spain

Pinkston, Daniel Patrick 20 July 2012 (has links)
The Esdolomada Sandstone member 2 crops out in the Tremp-Graus Basin of north-central Spain and forms the uppermost part of the Eocene Roda Formation. The second Sandstone unit within the Esdolomada member (ESD2) consists of bioturbated and shell-rich, very-fine sandstones as well as stacked sets of fine- to coarse-grained cross-stratified sandstones. The overall upward trend in the member is commonly upward thickening and coarsening of beds into and through the cross-stratified interval, though at some few locations there is no obvious trend or even upward thinning of beds. The internal architecture of the member is one in which groups of beds lie between master surfaces that dip highly obliquely to the migration direction of the individual cross strata. The ESD2 is interpreted to be a shelf tidal sand bar within the overall transgressive Esdolomada Sandstone member. It is likely that these bars migrated in a coast parallel fashion, as suggested by the cross-bed orientations, but also accreted laterally away from the coast along the seaward-dipping master surfaces. LIDAR (light detection and ranging) data collection for the Esdolomada member was attempted along the Isábena River near the village of Roda de Isábena, with a total lateral coverage of approximately 3 kilometers. Detailed outcrop measurements were made in accessible areas along the same transect. Outcrop analogs are the best source of data to understand reservoir heterogeneities and to build reservoir analogs for fluid flow simulations. Sand-rich, offshore tidal sandbodies are usually surrounded by marine mudstones, and are recognized from their very orderly stacking of cross-stratified sets (more orderly than in fluvial settings) , their complex internal architecture of master surfaces dipping obliquely to the direction of migration of the contained cross strata and their significant sandstone/mudstone heterogeneities. Tidal bar systems such as the ESD2 are appealing hydrocarbon prospects for several reasons. Primarily, they are relatively coarse grained, have a high degree of lateral continuity, and are relatively clean sands. In places where sand beds are stacked, they create enough thickness to offer good vertical permeability; however, mud-draped cross-beds can create heterogeneities in this type of system that buffer fluid flow. Due to a fairly unsuccessful attempt to obtain LIDAR coverage of the ESD2, in order to build an analog reservoir model, surfaces were instead based on measured sections and outcrop photomosaics. Using Schlumberger’s Petrel software, facies logs were created from measured section data, and then interpolated to make a facies and porosity model. / text

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