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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.
1

Instrumentation and control of an industrial sewing machine

Mattie-Suleiman, Eman A. January 1997 (has links)
No description available.
2

Propellant Feeding System of a Liquid Rocket With Multiple Engines

Miquel, Valentin January 2020 (has links)
Multiengine first stages are the new trend in recent rockets. Reusability and an oxygen/methane based engine complete this picture. ArianeGroup wants to develop its own rocket following these principles. This thesis presents the study of the feeding system for a seven Prometheus engine rocket. Several ways of connecting propellant tanks to engines were proposed and analyzed. Two configurations were selected and studied with more detail. One consists of a main feeding line which is then split in seven secondary lines. The other one adds one rank of pipes to reduce the number of feeding valves. Their performances were assessed according to classic space industry drivers. Furthermore, the impact of the two solutions on the efficiency of the tank was evaluated. CAD drawings and simulation models were made and could be a base for future work if one of the systems is chosen. The study shows that a falcon 9 like feeding system is performant in terms of mass and pressure losses but another cost-effective configuration is possible and gives good results. / Första stegen med flera motorer är den nya trenden i de senaste raketerna. Återanvändbart och en syre och metan-baserad motor kompletterar denna bild. ArianeGroup vill utveckla sin egen raket enligt dessa principer. Denna avhandling presenterar studien av drivmedelsrör för en sju Prometheus-motorraket. Flera sätt att ansluta drivmedelstankar till motorer föreslogs och analyserades. Två konfigurationer valdes ut och studerades mer detaljerat. En består av en huvudlinje som sedan delas upp i sju sekundära linjer som på SpaceX Falcon 9. Den andra lösningen lägger till en rang av rör för att minska antalet ventiler. Deras prestanda utvärderades först enligt klassiska kriterier för rymdindustrin. Dessutom utvärderades de två lösningarnas påverkan på tankens effektivitet. CAD-ritningar och simuleringsmodeller gjordes och kan vara en bas för framtida arbeten om ett av systemen väljs. Studien visar att ett Falcon 9-liknande konfiguration har bättre prestanda när det gäller massa och tryckförluster men en annan kostnadseffektiv konfiguration är möjlig och ger goda resultat.
3

Comparative Studies in the Functional Morphology of Lizard Feeding: Kinematics, Behavior, and Biomechanics

McBrayer, Lance D. 12 November 2002 (has links)
No description available.
4

Impact of feed form and nutrient distribution in an automated commercial broiler feeding system

Hancock, Christopher J.K. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / R. Scott Beyer / The modern poultry industry uses auger feed lines to transport feed for broilers to pans to make feed available for them while greatly reducing labor costs. The feed given to broilers is manufactured at significant cost into a pelleted form. Pellets reduce broiler production costs by increasing feed intake and growth rate while reducing feed. Pellet quality is expressed using a method called the Pellet Durability Index (PDI). A series of studies was conducted to determine the effects of these destructive forces on both pellet quality and nutritive value. In Experiment 1, it was found that pellets of 78 and 86 PDI had 30% more fines in the final pan compared to the initial pan, but there was no significant difference between the two diets. In Experiment 2, a significant difference existed between a 23 PDI diet and an 82 PDI diet in the percentage of fines found at 12 selected pans. This indicates destruction occurring along the length of the feed line. In Experiment 3, soybean oil was applied to the exterior of the pellets and they were transported through the feed line. A significant difference in the amount of fat at each collection site was found, as the fat was removed from the exterior of the pellets in earlier pans, indicating destructive forces having an effect on the pellets. In Experiment 4, whole sorghum was used to create four diets with similar PDI. The feed was then placed in the feed line, collected at twelve locations, and analyzed for crude fat, CP, DM, ash and Ca. The results indicated the presence of whole sorghum in the pellets had no effect on percent fines or nutrient values. In Experiment 5, three diets with different PDI were transported through the feed line. Five collection sites were selected. Results indicate that high quality pellets withstand handling while pellets below 68 PDI show increased fine percentage. These experiments indicate pellets are damaged during transport in the feed line, but nutrients remain the same unless they are on the exterior of the pellet.
5

Prediction of cow fertility based on productivity traits in dairy cattle under different production systems

Banda, Liveness Jessica January 2014 (has links)
A study to examine factors that influence dairy cattle fertility was conducted in the United Kingdom (UK) and Malawi. Productivity data from the UK comprising 56,014 records from 574 Holstein cows were retrieved from a database at Scotland’s Rural College Dairy Research Centre in Dumfries. The cows were of either high (select) or average (control) genetic merit and fed total mixed rations with high or low forage. These formed four production systems - high forage select (HFS), low forage select (LFS), high forage control (HFC) and low forage control (LFC). Data from Malawi were obtained through a baseline survey in 67 smallholder farms and monitoring of 28 and 62 dairy cows from smallholder farms and a commercial farm, respectively. The breeds were Holstein-Friesians and Holstein-Friesian x Malawi Zebu crosses predominantly fed forages supplemented with concentrates. Some cows were fitted with accelerometers to enable monitoring of cow activity which was then related to cow fertility and energy balance. The data were analysed using descriptive statistics, mixed models and logistic regression models using SAS 9.3. The UK data showed that production system significantly (p<0.05) influenced milk yield, body energy content (BEC) and fertility. BEC is a trait that indicates absolute level of energy in the body per day regardless of energy use and intake the previous day. Daily milk yield of LFS cows was 35±0.1 (mean±SEM) litres which was significantly (p<0.05) higher than that of LFC (30.4±0.1 litres), HFS (27.5±0.1 litres) and HFC (24.3±0.1 litres) cows. LFS cows also had the highest milk yield acceleration to peak milk yield (0.51 litres/day/day) than (LFC 0.47±0.02 litres/day/day), HFC (0.47±0.03 litres/day/day) and HFS (0.46±0.03 litres/day/day) cows. The interval from calving to nadir BEC was 68±5, 83±6, 88±5 and 106±6 days for LFC, LFS, HFC and HFS cows, respectively. Days to first high luteal activity (DFHLA) and days to successful service (DSS) were significantly different with production system and genetic merit, respectively. LFC cows had DFHLA of 27±2 days (mean±SEM) which were significantly lower (p<0.05) than those of HFC (30±3 days), HFS (30±2 days) and LFS (35±3 days) cows. Average genetic merit cows had significantly lower (p<0.05) DSS (119±5 days, mean±SEM) than high genetic merit cows (132±5 days). Results from data collected in Malawi showed variations that reflected differences in management and other environmental factors. Average daily milk yield per lactation in Malawi was 13.3±4.9 (mean±SD) litres. Fertility traits in the UK herd were better than those in Malawi herds. The average DFHLA in Malawi was 79±29 days while in the UK it was 31±18 days. Cow activity in both the UK and Malawi farms varied with the feeding system, genetic merit and BEC. Select cows on home grown feeding system were more active (motion index =6250±40), stood longer (13.4±0.04 hours/day) and spent more time eating (5.6±0.32 hours/day, mean±SEM) than select cows on by products feeding system that had motion index, standing and eating time of 5166±37, 11.9±0.04 hours/day and 4.6±0.16 hours/day, respectively. Genetic merit, lactation number, days to first observed oestrus, calving BEC, service BEC and service milk yield were significant predictors of pregnancy to first insemination (p<0.05) while genetic merit, milk yield, percentage BEC between calving and service, service milk yield and service BEC were significant predictors (p<0.05) of pregnancy to the first three inseminations. Validation of models derived showed C-statistics of the receiver operating characteristic (ROC) curve of 0.66 (95% confidence interval (CI): 0.57 to 0.75) and 0.65 (CI: 0.55-0.75), respectively. It is concluded that genetic merit, feeding system, parity, energy status and stage of lactation are the major factors that determine the likelihood of achieving pregnancy following insemination. Models developed have a potential to predict the probability of pregnancy to an insemination at an acceptable level of accuracy.
6

Enhancement of Industrial Horizontal Rubber Injection Moulding Machine Feeding System

John, Minchin, Balakrishnan, Krishnakumar January 2021 (has links)
This study aims to improve the design of the feeding system of industrial horizontal rubber injection moulding machines. There are many ways to implement this research. Still, the suitable design is to implement such a mechanism that will help reduce the operator intervention in the feeding system of the injection moulding machine. The FEM analysis is used to understand the real-world situation on the feed part or assembly. This analysis also provides the ability to detect the potential issues in the design, including the tension area of design and the weak spots. In the industrial horizontal rubber injection moulding machine, the same technique is used to evaluate the feeding system and based on it, the roller conveyor is designed. The 3D model is implemented using Cad software. The selection of motor for the roller conveyor and the power transmission system is also extracted to maintain the quality and enhance the feeding system's productivity. In the research, a design is presented to improve the feeding system in which the conveyor belt is designed, which provides complete support for the feeding system.
7

Rôle de Ctenocephalides felis (bouché, 1835) [Siphonaptera Pulicidae] dans la transmission de Bartonella spp. [Rhizobiales Bartonellaceae] et moyens de contrôle / Role of Ctenocephalides felis (Bouché, 1835) [Siphonaptera Pulicidae] in the transmission of Bartonella spp. and control

Bouhsira, Emilie 25 April 2014 (has links)
Ctenocephalides felis est une espèce de puce cosmopolite parasitant majoritairement les carnivores domestiques. Elle est vectrice de nombreux agents pathogènes zoonotiques dont les bactéries du genre Bartonella, bactéries intracellulaires facultatives. La compétence vectorielle de cette puce a été investiguée pour B. henselae, B. quintana, B. clarridgeiae, B. tribocorum et B. birtlesii. Dans ces conditions expérimentales, utilisant un système de gorgement sur membrane, ces espèces ont persisté pendant les trois jours d'une première étude, et pour B. henselae durant les 13 jours de survie des puces, dans une seconde étude. Les cinq espèces de bartonelles ont été retouvées dans les fèces. Pour ces cinq espèces, nos résultats montrent une absence de transmission verticale transovarienne chez la puce et suggèrent une possibilité de contamination horizontale. Nous proposons enfin un protocole original d'évaluation de l'efficacité d'un traitement antiparasitaire chez le chat, pour prévenir sa contamination par Bartonella spp. / Ctenocephalides felis is a cosmopolitan flea species mainly parasitizing pets, transmitting several pathogens of veterinary and zoonotic importance including the facultative intracellular bacteria of the genus Bartonella. The vector competence of this flea was investigated for B. henselae, B. quintana, B. clarridgeiae, B. tribocorum and B. birtlesii, using an artificial feeding system. In these experimental conditions, these bartonellae proved to persist for three days, in a first study, while B. henselae persisted for the 13 days of its life span, in a second study. All five bartonellae were excreted in the flea's faeces. On the whole, these five species were not transmitted transovarially in the fleas, though horizontal transmission was suggested. Furthermore, we propose an original protocol allowing the evaluation of the efficacy of ectoparasiticidal products against Bartonella spp. infection in cats.
8

Optimal Design of Feeding System in Steel Castings

Tavakoli, Ruhollah 20 September 2009 (has links) (PDF)
In the present study, the optimal design of feeding system in steel sand-mold castings is considered. The first part of this research includes fundamental studies on the physics of shrinkage defect formation during the casting process. The results of these studies lead to new findings on the mechanism of shrinkage defect formation, effect of melt quality on the distribution of defects within the castings and the connection between shrinkage and gases defects. The theoretical analysis of thermal criterion functions for the prediction of shrinkage defects in castings and introducing new criterion function with fewer shortcomings can be accounted as the other finding of this part. A new model was introduced in the second part of this research for the purpose of optimal design of feeding system in the shape casting processes. In this model the optimal design problem is formulated as a point-wise constrained topology optimization problem. Unlike alternative methods, the presented method does not require any predesigned feeding system as an initial guess. Using the functional analysis on the infinite-dimensional function spaces, a numerically efficient method was introduced to solve the optimal design problem in this study. By using extensive numerical experiments, capabilities and limitations of the presented method were studied in the last part of this research.
9

Caracterização do modelo de agroindustrialização de pequeno porte voltado à propriedade rural familiar do Município de Guarapuava - Pr

Nychai, Luci 25 January 2005 (has links)
Made available in DSpace on 2017-07-10T19:25:23Z (GMT). No. of bitstreams: 1 Luci Nychai.pdf: 733855 bytes, checksum: e3ff3acb90175b9f4c43fe2c307338fe (MD5) Previous issue date: 2005-01-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This trial aimed on featuring small agro-industrialization from Guarapuava-PR, when familiar rural farms were inserted and highlighted some survival aspects at the market as a sustainable factor. It was taking into account the agroindustries survey, regarding feeding and non-feeding systems, which are part of secondary economical branch, as well as the small (1 to 50 hectares), rural and familiar farm profile, also integrated to cooperativeness. As a consequence, it was used a sample of 218 farms linked to Cooperative of Micro and Small Producers from Guarapuava and a confidential statistical level of 95% so, there was a 5 % of error. The insertion of agro-industrial units from The Program Farmer Factory was also considered. At the secondary sector, there are 70.83 % of enterprising units that belong to the non-feeding agro-industrial system and 29.17 % are from agro-feeding system, but 26.18 % of them have there production guided to agro-industrialization. The forest raw material is used in 64.59 % of agro-industries while 35.14 % of farming industries use it. Observing the familiar rural farms studied, it was possible to record that 26.60 % of them applied some king of agro-industrialization, formal or rudimental. Regarding, the Program Farmer Factory from 1999 to 2004, it was recorded 38 units, of them 2.63% in implantation and adjustment; 7.89 % in studied of economical viability; 7.89 % inactive; 10.53 % definitely closed and 71.05 % in activity. These results drive through a great challenge, which is the insertion of small familiar rural farm at the sustained agro-industrialization process, mainly because of the economical-financial aspect. The biggest difficulties were the absence technology; technical ability; competitiveness; strategic administration; quality and safety of products, but the most important was trading. Agro-industries enterprises by themselves do not show profitable results. The agricultureindustrialization development of small size, concerning the family rural farm, depends on the pattern set up by of formatted and strategic alliances through partnerships revealing a systemic pattern, as well as the necessity of working with several products due to the absence of scale production. / Caracterizou-se o modelo de agroindustrialização de pequeno porte do município de Guarapuava-PR, ao ser evidenciada a inserção da propriedade rural familiar e ressaltados os aspectos de sobrevivência no mercado como fator de sustentabilidade. Considerou-se o levantamento das agroindústrias dos sistemas alimentar e não alimentar que compõem o setor econômico secundário, bem como o perfil da pequena propriedade rural familiar, de 1 a 50 hectares, integrada ao cooperativismo. Para tanto, utilizou-se uma amostra de 218 estabelecimentos vinculados à Cooperativa de Micros e Pequenos Produtores de Guarapuava, com nível de confiabilidade estatística de 95 % e erro de 5 %. Também, considerou-se a inserção das unidades agroindustriais do Programa Fábrica do Agricultor. No cenário do setor secundário, 70,83 % das unidades empresariais pertencem ao sistema agroindustrial não alimentar e 29,17 % ao sistema agroalimentar, sendo que 26,18 % das unidades têm sua atividade produtiva voltada para agroindustrialização. A matéria-prima oriunda da floresta é utilizada em 64,59 % das agroindústrias e da agropecuária em 35,14%.Das propriedades rurais familiares investigadas, 26,60 % apresentaram algum tipo agroindustrialização formal ou artesanal. Quanto à inserção ao Programa Fábrica do Agricultor, no período de 1999 a 2004, levantou-se um total de 38 unidades, sendo 2,63 % em processo de implantação e adaptação, 7,89 % em estudo de viabilidade econômica, 7,89 % inativas, 10,53 % fechadas e 71,05 % em operação. Os resultados remetem ao grande desafio que é a inserção do pequeno estabelecimento rural familiar no processo de agroindustrialização sustentado, essencialmente quanto ao aspecto econômico-financeiro. As principais dificuldades referem-se à tecnologia, capacitação, competitividade, gestão estratégica, qualidade e segurança dos produtos e, principalmente à comercialização. As empresas agroalimentares, isoladamente, não exemplificam resultados lucrativos. O desenvolvimento da agroindustrialização de pequeno porte, voltado à propriedade rural familiar, está condicionado ao modelo de alianças estratégias formatadas por meio de parcerias as quais configuram o modelo sistêmico, além da necessidade de se trabalhar com produtos diferenciados em contraponto à ausência da escala de produção.
10

Caracterização do modelo de agroindustrialização de pequeno porte voltado à propriedade rural familiar do Município de Guarapuava - Pr

Nychai, Luci 25 January 2005 (has links)
Made available in DSpace on 2017-05-12T14:48:45Z (GMT). No. of bitstreams: 1 Luci Nychai.pdf: 733855 bytes, checksum: e3ff3acb90175b9f4c43fe2c307338fe (MD5) Previous issue date: 2005-01-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This trial aimed on featuring small agro-industrialization from Guarapuava-PR, when familiar rural farms were inserted and highlighted some survival aspects at the market as a sustainable factor. It was taking into account the agroindustries survey, regarding feeding and non-feeding systems, which are part of secondary economical branch, as well as the small (1 to 50 hectares), rural and familiar farm profile, also integrated to cooperativeness. As a consequence, it was used a sample of 218 farms linked to Cooperative of Micro and Small Producers from Guarapuava and a confidential statistical level of 95% so, there was a 5 % of error. The insertion of agro-industrial units from The Program Farmer Factory was also considered. At the secondary sector, there are 70.83 % of enterprising units that belong to the non-feeding agro-industrial system and 29.17 % are from agro-feeding system, but 26.18 % of them have there production guided to agro-industrialization. The forest raw material is used in 64.59 % of agro-industries while 35.14 % of farming industries use it. Observing the familiar rural farms studied, it was possible to record that 26.60 % of them applied some king of agro-industrialization, formal or rudimental. Regarding, the Program Farmer Factory from 1999 to 2004, it was recorded 38 units, of them 2.63% in implantation and adjustment; 7.89 % in studied of economical viability; 7.89 % inactive; 10.53 % definitely closed and 71.05 % in activity. These results drive through a great challenge, which is the insertion of small familiar rural farm at the sustained agro-industrialization process, mainly because of the economical-financial aspect. The biggest difficulties were the absence technology; technical ability; competitiveness; strategic administration; quality and safety of products, but the most important was trading. Agro-industries enterprises by themselves do not show profitable results. The agricultureindustrialization development of small size, concerning the family rural farm, depends on the pattern set up by of formatted and strategic alliances through partnerships revealing a systemic pattern, as well as the necessity of working with several products due to the absence of scale production. / Caracterizou-se o modelo de agroindustrialização de pequeno porte do município de Guarapuava-PR, ao ser evidenciada a inserção da propriedade rural familiar e ressaltados os aspectos de sobrevivência no mercado como fator de sustentabilidade. Considerou-se o levantamento das agroindústrias dos sistemas alimentar e não alimentar que compõem o setor econômico secundário, bem como o perfil da pequena propriedade rural familiar, de 1 a 50 hectares, integrada ao cooperativismo. Para tanto, utilizou-se uma amostra de 218 estabelecimentos vinculados à Cooperativa de Micros e Pequenos Produtores de Guarapuava, com nível de confiabilidade estatística de 95 % e erro de 5 %. Também, considerou-se a inserção das unidades agroindustriais do Programa Fábrica do Agricultor. No cenário do setor secundário, 70,83 % das unidades empresariais pertencem ao sistema agroindustrial não alimentar e 29,17 % ao sistema agroalimentar, sendo que 26,18 % das unidades têm sua atividade produtiva voltada para agroindustrialização. A matéria-prima oriunda da floresta é utilizada em 64,59 % das agroindústrias e da agropecuária em 35,14%.Das propriedades rurais familiares investigadas, 26,60 % apresentaram algum tipo agroindustrialização formal ou artesanal. Quanto à inserção ao Programa Fábrica do Agricultor, no período de 1999 a 2004, levantou-se um total de 38 unidades, sendo 2,63 % em processo de implantação e adaptação, 7,89 % em estudo de viabilidade econômica, 7,89 % inativas, 10,53 % fechadas e 71,05 % em operação. Os resultados remetem ao grande desafio que é a inserção do pequeno estabelecimento rural familiar no processo de agroindustrialização sustentado, essencialmente quanto ao aspecto econômico-financeiro. As principais dificuldades referem-se à tecnologia, capacitação, competitividade, gestão estratégica, qualidade e segurança dos produtos e, principalmente à comercialização. As empresas agroalimentares, isoladamente, não exemplificam resultados lucrativos. O desenvolvimento da agroindustrialização de pequeno porte, voltado à propriedade rural familiar, está condicionado ao modelo de alianças estratégias formatadas por meio de parcerias as quais configuram o modelo sistêmico, além da necessidade de se trabalhar com produtos diferenciados em contraponto à ausência da escala de produção.

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