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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.
301

Análise econômica e desempenho de frangos de corte submetidos a dietas comerciais com matriz nutricional valorizada e suplementadas com superdosagem de fitase / Economic analysis and performance of broiler chickens submitted to commercial diets with valorized nutritional matrix and supplemented with superdosagem of phytase

Rafael Araújo Nacimento 09 February 2018 (has links)
O uso de fitase em dietas destinadas a frangos de corte é um consenso na indústria avícola. Juntamente ao emprego de 500FTU/kg de fitase, a recomendação de reduções de cálcio (Ca) e fósforo disponível (Pd) na matriz nutricional é tida como uma estratégia para a redução dos custos da dieta sem causar redução no desempenho dos animais. Com isso, foi hipotetizado que o uso de superdosagem de fitase (1500FTU/kg) em dietas com matriz nutricional valorizada para Ca e Pd, energia metabolizável (EM) e proteína bruta (PB), apresentaria menores custos de dieta e maior lucratividade, sem acarretar redução no desempenho dos animais. O presente estudo teve como objetivo avaliar os efeitos da redução de Ca, Pd, PB e EM em dietas comerciais suplementadas com superdosagem de fitase sobre o custo de dietas e margem de lucro, bem como o desempenho, mineralização óssea e rendimento de carcaça de frangos de corte de 1 a 42d. Para tanto, foram utilizados 1200 pintos de um dia (Cobb500) distribuídos aleatoriamente em um programa de alimentação comercial composto por dieta sem redução nutricional e sem suplementação enzimática ( C ); dietas reduzidas em 23kcal, 0,23%, 0,10% e 0,09% na fase 1 e 2, e reduzida em 23kcal, 0,24%, 0,11% e 0,10% de EM, PB, Ca e Pd na fase 3, suplementadas com 500FTU/kg de fitase (500); dietas reduzidas em 29kcal, 0,29%, 0,13%, 0,12% nas fases 1 e 2, e dietas reduzidas em 30kcal, 0,31%, 0,14% e 0,13% de EM, PB, Ca e Pd na fase 3, suplementada com 1000FTU/kg de fitase (1000); e dietas reduzidas em 34kcal, 0,34%, 0,15%, 0,14% nas fases 1 e 2, e dietas reduzidas em 35kcal, 0,36%, 0,16% e 0,15% de EM, PB, Ca e Pd na fase 3, suplementada com 1500FTU/kg de fitase (1500); com 25 repetições por tratamento e 12 aves por unidade experimental. Os dados foram analisados pelo PROC GLM do SAS (2012) e quando atendidas, os dados foram submetidos ao teste de comparação de médias (Tukey) a 5% de probabilidade. O uso de superdosagem de fitase promoveu o desempenho, cinzas ósseas e rendimento de carcaça e pernas similares entre os animais (p<0.05). No entanto, os animais submetidos a dietas suplementadas com 1500FTU/kg de fitase apresentaram melhor rendimento de peito (p=0.037). Além disso, as dietas suplementadas com fitase apresentaram menor custo de dieta e maior lucratividade (p<0001). Em conclusão, neste estudo, a utilização de superdosagem de fitase em dietas com matriz nutricional valorizada para Ca, Pd, EM e PB apresenta-se como uma alternativa viável para a redução de custos e aumento da lucratividade, sem afetar o desempenho de frangos de corte aos 42d. / The use of phytase in diets for broilers is a consensus in the poultry industry. Together with the use of 500 FTU/kg of phytase, the recommendation of reductions in calcium (Ca) and available phosphorus (aP) in the nutritional matrix is taken as a strategy to reduce dietary costs without causing a reduction in animal performance. Therefore, it was hypothesized that the use of phytase superdosings (1500 FTU/kg) in diets with nutritional matrix valued for Ca and aP, metabolizable energy (ME) and crude protein (CP) would present lower dietary costs and higher profitability, with no effects on animal performance. The objective of the present study was to evaluate the effects of reduction of Ca, aP, CP and ME in commercial diets supplemented with phytase superdosing on the cost of diets and profit margin, as well as performance, bone mineralization and carcass dressing of broiler chickens from 1 to 42d of age. For this purpose, 1200 day-old chicks (Cobb500) were randomly distributed in a commercial feeding program composed of a diet without nutritional reduction and without enzymatic supplementation (C); diets reduced by 23kcal, 0.23%, 0.10% and 0.09% in phase 1 and 2, and reduced by 23kcal, 0.24%, 0.11% and 0.10% of ME, CP, Ca and aP in stage 3, supplemented with 500 FTU/kg of phytase (500); diets reduced by 29 kcal, 0.29%, 0.13%, 0.12% in phases 1 and 2, and diets reduced by 30 kcal, 0.31%, 0.14% and 0.13% of ME, CP, Ca and aP in stage 3, supplemented with 1000 FTU/kg of phytase (1000); and diets reduced by 34 kcal, 0.34%, 0.15%, 0.14% in phases 1 and 2, and diets reduced by 35 kcal, 0.36%, 0.16% and 0.15% of ME, CP, Ca and aP in stage 3, supplemented with 1500 FTU/kg of phytase (1500); with 25 replicates per treatment and 12 birds per experimental unit. The data were analyzed by PROC GLM of SAS (2012) and when met, the data were submitted to the test of comparison of averages (Tukey) at 5% of probability. The use of phytase superdosing promoted performance, bone ash, and carcass dressing and leg yield similar among treatments (p>0.05). However, animals fed diets supplemented with 1500 FTU/kg of phytase showed greater breast yield (p=0.037). In addition, diets supplemented with phytase had lower diet cost and greater profitability (p<0001). In conclusion, in this study, the use of phytase superdosing in diets with nutritional matrix valued for Ca, aP, ME and CP is a viable alternative for reducing costs and increasing profitability, without affecting the performance of broiler chickens at 42d of age.
302

Development and practical application of unhairing method without using sulfide

Takase, Kazuya, Terashima, M., Yoshimura, K. 24 June 2019 (has links)
Content: Leather manufacturing industry uses a lot of water and chemicals, and it discharges large amounts of wastewater. The processing a large amounts of wastewater requires a huge cost. Therefore, reduction of amount of a pollution load in wastewater is a theme in many countries around the world. During the leather process, a lot of pollutants occur in the unhairing process. Some estimate that the amount of pollution generated in the unhairing process accounts for 70% of the entire leather manufacturing process. In this unhairing process, usually a large amount of sulfide is used. Sulfide is known to generate hydrogen sulfide and cause damage to the drain pipe. In Tokyo, strict criteria are set for draining sulfide to sewers. Therefore, reducing the amount of sulfide used is an important task for tanner. In addition, since sulfide has no degreasing effect, a large amount of surfactant is required in the unhairing process. However, to reduce the cost and the load of the wastewater, it is also required to reduce the amount of the surfactant used. Furthermore, in recent years, the types of usable surfactants have also been limited. Therefore, development of a method of effectively removing hair loss and degreasing without using a sulfide is urgent for the leather manufacturing industry. On the other hand, pelts are widely used as raw materials for foods such as gelatin and collagen casing, cosmetics, and pharmaceuticals. However, sulfides are not originally recognized as food additives. Therefore, some companies are concerned about using pelts as a raw material for food using sulfide in the unhairing process. Also from this point of view, it is necessary to develop an unhairing method without using sulfides. The method using sodium hydroxide has been studied for a long time. However, this method is hard in handling, and is difficult to set conditions such as concentration and temperature. That is, while successful at the experimental level, it has not been put to practical use. Therefore, we studied a method to solve the above problem using sodium hydroxide. The method developed this time can reduce the pollutant in waste water, and the amount of water used in the unhairing process to 1/10 or less of the conventional one. Moreover, since it is not influenced by water temperature, it made it possible to stably remove hair irrespective of the season. The finished leather kept sufficient strength. In addition, sodium hydroxide reacts with fat in the skin and turns it into soap, so it shows the degreasing effect and contributes to reduce the dosage of degreasing agent. Take-Away: development of unhairing method without using sulfide contributes to reduce the dosage of degreasing agent reduce the pollutant in waste water
303

Size-effect of pd nanoparticles supported on zro2 in the catalytic reduction of no by h2

Joh, Young Woo 01 May 2011 (has links)
Size-selected Pd nanoparticles were synthesized by the reverse-micelle encapsulation method and deposited on a ZrO2 support for the catalytic NO reduction by H2. All of our samples were found to be highly selective, but a significant size effect was not seen for Pd nanoparticles of between 1.2 nm and 5.5 nm. Ultra-small Pd clusters of less than 1 nm were found to be much less active, and are assumed to be affected by an encapsulation effect of the support. Catalyst activity was comparable to that of literature, and is applicable to H2-SCR research.
304

Retardation of autoxidation in ramyon, deep-fried instant noodle

Rho, Kwang Lae January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
305

Electrochemical reductions of diphenyldiazomethane and azobenzene: the effect of electroinactive proton donors

Cheng, Spencer Shu-Tsu. January 1986 (has links)
Call number: LD2668 .T4 1986 C443 / Master of Science / Chemistry
306

AN ONBOARD PROCESSOR FOR FLIGHT TEST DATA ACQUISITION SYSTEMS

Wegener, John A., Blase, Gordon A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Today’s flight test programs are experiencing increasing demands for a greater number of high-rate digital parameters, competition for spectrum space, and a need for operational flexibility in flight test instrumentation. These demands must be met while meeting schedule and budget constraints. To address these various needs, the Boeing Integrated Defense System (IDS) Flight Test Instrumentation group in St. Louis has developed an onboard processing capability for use with airborne instrumentation data collection systems. This includes a first-generation Onboard Processor (OBP) which has been successfully used on the F/A-18E/F Super Hornet flight test program for four years, and which provides a throughput of 5 Mbytes/s and a processing capability of 480 Mflops (floating-point operations per second). Boeing IDS Flight Test is also currently developing a second generation OBP which features greatly enhanced input and output flexibility and algorithm programmability, and is targeted to provide a throughput of 160 Mbytes/s with a processing capability of 16 Gflops. This paper describes these onboard processing capabilities and their benefits.
307

An investigation on design and analysis of micro-structured surfaces with application to friction reduction

Sayad Saravi, Samira January 2014 (has links)
Drag reduction in wall-bounded flows can be achieved by the passive flow control technique using riblets and surface grooves aligned in the mean direction of an overlying turbulent flow. They were inspired by the skin of fast sharks covered with small longitudinal ribs on their skin surfaces. Although it was found that the drag reduction depends on the riblets’ geometrical characteristics, their physical mechanisms have not yet been fully understood in the scientific terms. Regarding riblets sizing, it has been critically explained in the literature how riblets with vanishing size interact with the turbulent flow and produce a change in the drag proportional to their size. Their shapes are focused upon because these are most significant from a technological perspective, and also less well understood. Different riblet shapes have been designed, some with complicated geometries, but except for the simple ones, such as U and V grooves, there has not been enough study regarding shape features. Therefore, special effort is undertaken to the design of an innovative type of ribleted surface, e.g. the Serrate-Semi-Circular shape, and its effect on the skin friction and drag reduction. In this work, the possible physical mechanisms of riblets for turbulent drag reduction have been explored. The modelling and experiments concerning the relationship between the riblets features and the turbulent boundary layer structure have also been reviewed. Moreover, numerical simulations on riblets with different shapes and sizes are presented and studied in detail. An accurate treatment based on k-ε turbulence model was adopted to investigate the flow alteration and the consequent drag reduction on ribleted surfaces. The interaction of the overlying turbulent flow with riblets and its impact on their drag reduction properties are further investigated. In addition, the experimental facilities, instrumentation (e.g. hotwires) and measurement techniques (e.g. time-averaged turbulence structure) have been employed to experimentally investigate the boundary layer velocity profiles and skin friction for smooth and micro-structured surfaces (the proposed riblet shape, respectively and the presented new design of riblets with serration inside provides 7% drag reduction. The results do not show significant reduction in momentum transfer near the surface by riblets, in particular, around the outer region of the turbulent boundary layer. Conclusions with respect to the holistic investigation on the drag reduction with Serrate-Semi-Circular riblets have been drawn based on the research objectives as achieved. Recommendations for future work have been put forward particularly for further future research in the research area.
308

Study of Single and Ensemble Machine Learning Models on Credit Data to Detect Underlying Non-performing Loans

Li, Qiongzhu January 2016 (has links)
In this paper, we try to compare the performance of two feature dimension reduction methods, the LASSO and PCA. Both simulation study and empirical study show that the LASSO is superior to PCA when selecting significant variables. We apply Logistics Regression (LR), Artificial Neural Network (ANN), Support Vector Machine (SVM), Decision Tree (DT) and their corresponding ensemble machines constructed by bagging and adaptive boosting (adaboost) in our study. Three experiments are conducted to explore the impact of class-unbalanced data set on all models. Empirical study indicates that when the percentage of performing loans exceeds 83.3%, the training models shall be carefully applied. When we have class-balanced data set, ensemble machines indeed have a better performance over single machines. The weaker the single machine, the more obvious the improvement we can observe.
309

Novel pathway for microbial FE(III) reduction: electron shuttling through naturally occurring thiols

Wee, Seng Kew 08 June 2015 (has links)
The g-proteobacterium Shewanella oneidensis MR-1 reduces a wide range of terminal electron acceptors, including solid Fe(III) oxides. Pathways for Fe(III) oxide reduction by S. oneidensis include non-reductive (organic ligand-promoted) solubilization reactions, and either direct enzymatic, or indirect electron shuttling pathways. Results of the present study expand the spectrum of electron acceptors reduced by S. oneidensis to include the naturally occurring disulfide compounds cystine, oxidized glutathione, dithiodiglycolate, dithoidiproponiate and cystamine. Subsequent electron shuttling experiments demonstrated that S. oneidensis employs the reduced (thiol) form of the disulfide compounds (cysteine, reduced glutathione, mercaptoacetate, mercaptopropionate, and 2-nitro-5-thiobenzoate, cystamine) as electron shuttles to transfer electrons to extracellular Fe(III) oxides. The results of the present study indicate that microbial disulfide reduction may represent an important electron-shuttling pathway for electron transfer to Fe(III) oxides in anaerobic marine and freshwater environments.
310

The Effects of Ongoing Assessment During a Psychoeducational Evaluation

Elliot, Joseph 01 January 2015 (has links)
Statistically significant reductions in scores from initial pretreatment testing to subsequent pretreatment testing in self-report measures are a widespread phenomenon (Arrindell, 2001). If valid, these reductions reflect improvement in psychological functioning absent any formal treatment (Arrindell, 2001). Many explanations for these reductions in scores have been offered (Arrindell, 2001) including assessment reactivity (Epstein et al., 2005), social desirability (Henderson, Byrne, & Duncan-Jones, 1981); and mechanical responding (Bromet, Dunn, Connell, Dew, & Schulberg, 1986; Durham et al., 2002). However, relatively few studies have examined this phenomenon empirically. Even fewer studies have examined pretreatment improvements in parent ratings. The present study sought to replicate the pre-treatment effect and to evaluate potential causes of these changes, specifically, repeated assessment, social desirability, and mechanical responding. Additionally, the study examined the relationship between maternal depression and parent ratings. Participants included 28 self-referred mothers and their children, though only 17 completed the study in its entirety. Results indicated pretreatment reductions in maternal ratings of child symptomatology and parenting stress. Repeated assessment was not supported as a cause of pretreatment improvements (score reductions). Social desirability, however, may have been a factor in the mothers’ ratings. Mechanical responding did not appear as a likely cause. Maternal symptoms of depression were associated with less change over the course of the study. Clinical implications, study limitations, and suggestions for future research are discussed.

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