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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.
191

Stabilized hydrogen peroxide decomposition dynamics in one-dimensional columns

Schmidt, Jeremy T. January 2006 (has links) (PDF)
Thesis (M.S. in environmental engineering)--Washington State University, May 2006. / Includes bibliographical references (p. 12-13).
192

Instrumentation for pressure measurement during thermal decomposition of binders in multilayer ceramic capacitors

Ha, Sang-Woo. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 65-67). Also available on the Internet.
193

Modeling and Analysis of Manufacturing Systems with Multiple-Loop Structures

Zhang, Zhenyu, Gershwin, Stanley B. 01 1900 (has links)
Kanban and Constant Work-In-Process (CONWIP) control methods are designed to impose tight controls over inventory, while providing a satisfactory production rate. This paper generalizes systems with kanban or CONWIP control as assembly/disassembly networks with multiple-loop structures. We present a stochastic mathematical model which integrates the information control flows into material flows. Graph theory is used to analyze the multiple-loop structures. An efficient analytical algorithm is developed for evaluating the expected production rate and inventory levels. The performance of the algorithm is reported in terms of accuracy, reliability and speed. / Singapore-MIT Alliance (SMA)
194

Vegetation colonization of experimental grave sites in central Texas /

Callahan, Casey A. January 1900 (has links)
Thesis (M.A.)--Texas State University--San Marcos, 2009. / Vita. Appendix: leaves [32]-47. Reproduction permission applies to print copy: Blanket permission granted per author to reproduce. Includes bibliographical references (leaves [48]-51). Also available on microfilm.
195

The effects of insect on soft tissue decomposition

Fasano, Ann D. January 2013 (has links)
A primary goal of the forensic anthropologist is assisting in the estimation of a post-mortem interval. This assessment is largely based upon the degree and quality of soft tissue decomposition, influenced by factors including temperature, humidity, insect activity, carnivore and rodent activity, perimortem trauma and the depositional environment. While the effects of temperature on decomposition have been long appreciated and initially studied, little or no research has been conducted on the disruption of insect activity and how that disturbance may affect the decomposition process. This study was designed to determine if the exposure of skin surface of porcine remains to insect repellant (specifically, DEET) has an effect on the presence and overall activity of insects during decomposition. Two experiments were conducted in the spring and fall with results indicating that insect repellant slows the rate of decomposition. Such findings are important for criminal investigators requiring an accurate estimation of post-mortem time to appreciate those factors that may adversely affect the process and rate of soft tissue deterioration.
196

Arranging simple neural networks to solve complex classification problems

Ghaderi, Reza January 2000 (has links)
In "decomposition/reconstruction" strategy, we can solve a complex problem by 1) decomposing the problem into simpler sub-problems, 2) solving sub-problems with simpler systems (sub-systems) and 3) combining the results of sub-systems to solve the original problem. In a classification task we may have "label complexity" which is due to high number of possible classes, "function complexity" which means the existence of complex input-output relationship, and "input complexity" which is due to requirement of a huge feature set to represent patterns. Error Correcting Output Code (ECOC) is a technique to reduce the label complexity in which a multi-class problem will be decomposed into a set of binary sub-problems, based oil the sequence of "0"s and "1"s of the columns of a decomposition (code) matrix. Then a given pattern can be assigned to the class having minimum distance to the results of sub-problems. The lack of knowledge about the relationship between distance measurement and class score (like posterior probabilities) has caused some essential shortcomings to answering questions about "source of effectiveness", "error analysis", " code selecting ", and " alternative reconstruction methods" in previous works. Proposing a theoretical framework in this thesis to specify this relationship, our main contributions in this subject are to: 1) explain the theoretical reasons for code selection conditions 2) suggest new conditions for code generation (equidistance code)which minimise reconstruction error and address a search technique for code selection 3) provide an analysis to show the effect of different kinds of error on final performance 4) suggest a novel combining method to reduce the effect of code word selection in non-optimum codes 5) suggest novel reconstruction frameworks to combine the component outputs. Some experiments on artificial and real benchmarks demonstrate significant improvement achieved in multi-class problems when simple feed forward neural networks are arranged based on suggested framework To solve the problem of function complexity we considered AdaBoost, as a technique which can be fused with ECOC to overcome its shortcoming for binary problems. And to handle the problems of huge feature sets, we have suggested a multi-net structure with local back propagation. To demonstrate these improvements on realistic problems a face recognition application is considered. Key words: decomposition/ reconstruction, reconstruction error, error correcting output codes, bias-variance decomposition.
197

Dynamics of Early-Season Weed Management and Soybean Nutrition

Harre, Nick T. 01 May 2014 (has links)
The popularity of growers using only postemergence (POST) herbicides for weed management in soybean was enabled by the commercialization of glyphosate-resistant soybean. The efficacy and flexibility provided by this technology diminished the use of soil residual herbicides and arguably, increased soybean yield loss from early-season weed competition. While, the rapid evolution and biogeographical spread of herbicide-resistant weeds, especially glyphosate-resistant biotypes, has renewed interest into the use of soil residual products, herbicide-resistant soybean technologies continue to be developed that may once again entice growers into POST-only weed management systems. The commercial interest in soybean yield advancements justifies further characterizing the benefits provided by early-season weed control beyond those of herbicide-resistance management. Furthermore, as awareness heightens regarding techniques that will enhance the sustainability of agro-ecosystems, specific focus on resource utilization will help to evaluate the viability of this weed management strategy. Field experiments were conducted across four sites throughout southern Illinois in 2012 and 2013 to study the influence of early-season weed management strategies on soybean nutrient accumulation, grain yield parameters, and the acquisition of nutrients by broadleaved and grass weeds. Increasing periods of weed competition duration were established by removing weeds at heights of 10, 20, 30 or 45 cm with glyphosate. A weed-free treatment utilizing a comprehensive soil residual and POST herbicide program was included to implement a weed-free comparison. Two standard herbicide management strategies that simulate common grower practices were also evaluated for comparison: flumioxazin PRE followed by glyphosate POST and two sequential POST glyphosate applications. Averaged across all 11 mineral nutrients analyzed in this experiment, broadleaved weeds accumulated 149 and 108% more nutrients than grasses in 2012 and 2013, respectively. Competition from 20-cm weeds reduced the acquisition of N, P, Ca, Mg, S, Fe, B, Cu, and Zn by soybean in 2012; these nutrients in addition to K and Mn were reduced by the same level of competition in 2013. N and Fe were the nutrients in soybean most notably impacted by weed interference. Reductions in soybean grain yield were the result of competition with 30-cm weeds in 2012, and 10-cm weeds in 2013; while, both standard herbicide regimens yielded less than the weed-free treatment in 2013 only. Additionally in 2013, average soybean seed weight and grain oil content was reduced when weeds were not removed before a height of 10 and 20 cm, respectively. The rate of decomposition and nutrient release was measured for waterhemp and giant foxtail desiccated by glyphosate at heights of 10, 20, 30, and 45 cm in two southern Illinois soybean fields. Weed biomass was grown under greenhouse conditions to ensure homogeneity and litterbag methodology was utilized to track in situ mass and nutrient losses, expressed as a decay constant (k) regressed over time according to the single exponential decay model. The effect of specie and height both had a strong influence on the intrinsic properties of the weed biomass and the associated rate of decay. Concentrations of the recalcitrant cell wall components (cellulose, hemicellulose, and lignin) were generally greatest as weed height (plant age and development) increased and with giant foxtail compared with waterhemp. Ca, Mg, and S concentrations were greater in waterhemp, while N was greater in giant foxtail. N and K concentrations decreased with increasing weed height. After 16 weeks, 10-cm waterhemp and giant foxtail detritus had lost 10 and 12% more mass compared to the 45-cm height. Decomposition rates revealed mass loss was highest for 10-cm waterhemp (kD = 0.022) and lowest for 45-cm giant foxtail (kD = 0.011) and this process was negatively correlated to the overall amount of cell wall constituents (r = -0.73). Nutrient release rates followed a similar trend in that shorter (younger) weeds and waterhemp liberated nutrients more readily. Across all tested plant material, K was the nutrient most rapidly released, whereas, Ca was the most strongly retained nutrient. Although the pressing challenge of managing herbicide-resistant weeds justifies the implementation of early-season weed control tactics, this research suggests there are ancillary benefits that are provided by this strategy. The use of a robust, broad-spectrum soil residual herbicide program in conjunction with timely POST applications provides the foundation for early-season weed management, thereby minimizing non-crop nutrient use and enhancing the nutrient acquisition capacity in soybean. This strategy facilitates more sustainable crop production by requiring fewer supplemental nutritional inputs while also protecting grain yield.
198

Real-Time Contactless Heart Rate Estimation from Facial Video

Qiu, Ying 26 October 2018 (has links)
With the increase in health consciousness, noninvasive body monitoring has aroused interest among researchers. As one of the most important pieces of physiological information, researchers have remotely estimated heart rates from facial videos in recent years. Although progress has been made over the past few years, there are still some limitations, such as the increase in processing time with accuracy and the lack of comprehensive and challenging datasets for use and comparison. Recently, it was shown that heart rate information can be extracted from facial videos by spatial decomposition and temporal filtering. Inspired by this, a new framework is introduced in this thesis for remotely estimating the heart rate under realistic conditions by combining spatial and temporal filtering and a convolutional neural network. Our proposed approach exhibits better performance compared with that of the benchmark on the MMSE-HR dataset in terms of both the average heart rate estimation and short-term heart rate estimation. High consistency in short-term heart rate estimation is observed between our method and the ground truth.
199

Síntese, caracterização e estudo do comportamento térmico dos 2-metoxibenzoatos de lantanídeos no estado sólido

Siqueira, Adriano Buzutti de [UNESP] 18 July 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-18Bitstream added on 2014-06-13T20:06:29Z : No. of bitstreams: 1 siqueira_ab_dr_araiq.pdf: 1539576 bytes, checksum: 6e539e939ace621bbe4c448e761c8893 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram sintetizados no estado sólido os compostos Ln-2-MeO-Bz, sendo que Ln representa os lantanídeos trivalentes e Y (III) e 2-MeO-Bz representa o 2-methoxibenzoato. Os compostos foram sintetizados por adição estequiométrica, sob agitação, do ligante nas respectivas soluções de cloretos ou nitratos de lantanídeos. A precipitação dos compostos só ocorreram quando as soluções foram parcialmente evaporadas em banho maria. A caracterização dos compostos foi realizada utilizando-se de métodos convencionais: difratometria de raios X pelo método do pó, espectroscopia de absorção na região do infravermelho, análise elementar e as técnicas termoanalíticas TG/DTG (termogravimetria / termogravimetria derivada simultânea) e TG – DTA (termogravimetria - análise térmica diferencial simultânea) e DSC (Calorimetria exploratória diferencial). Estas técnicas puderam dar informações sobre desidratação, modos de coordenação, comportamento térmico, estequiometria e estrutura dos compostos sintetizados. Com os resultados das curvas TG e da complexometria, pôde-se estabelecer a fórmula geral de cada composto sintetizado. Pela análise dos difratogramas de raios X foi observado que todos os compostos sintetizados são cristalinos e que os compostos de lutécio e itérbio são isomorfos. A observação dos espectros de infravermelho teórico e experimental sugerem uma coordenação bidentada sem equalização de cargas entre o 2-metoxibenzoato e os seus respectivos centros metálicos. As curvas TG-DTA e DSC forneceram informações inéditas e importantes sobre o comportamento e a decomposição térmica dos compostos sintetizados. / Solid state Ln 2-MeO-Bz compounds, where Ln stands for trivalent La to Lu and Y (III) and 2-MeO-Bz is 2-methoxybenzoate, have been synthesized. The solid state compounds were prepared by stoichiometric relation adding slowly, with continuous stirring the ligand solution to the respective metal chloride or nitrate solutions. No precipitate was observed during the addition of sodium 2-methoxybenzoate; however the precipitate was obtained when the solution was evaporated in a water bath. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffraction, infrared spectroscopy, elemental analysis and complexometry, were used to characterize and to study the thermal behaviour of these compounds. The results led to information about composition, dehydration, coordination mode, structure, thermal behaviour and thermal decomposition of the isolated compounds. From TG curves and complexometry results, a general formula could be established for these compounds in the solid state. The X-ray powder patterns pointed out that the synthesized compounds have a crystalline structure without evidence concerning to the formation of isomorphous series, except the ytterbium and lutetium compounds. The experimental and theoretical infrared spectroscopy data suggest that 2-metoxibenzoate acts as a bidentate bond with an incomplete equalization of bond lenghts in the carboxylate anion. The TG-DTA and DSC curves provided previously unrerported information concerning the thermal behaviour and thermal decomposition of these compounds.
200

Sintese do sesquinitreto de uranio e seu uso como catalisador da reacao de termodecomposicao da amonia

ROCHA, SORAYA M.R. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:40:52Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:28Z (GMT). No. of bitstreams: 1 02950.pdf: 4952382 bytes, checksum: 1dddfe6ca71077632e2bdf2d56006ba7 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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