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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.
41

Da formação socioespacial à diferenciação dos circuitos espaciais agropecuários na região de Araçatuba (SP) / From the sociospacial training to the differentiation of circuits in agricultural region of Araçatuba (SP)

Bini, Danton Leonel de Camargo 03 March 2015 (has links)
A presente pesquisa analisa a formação socioespacial agropecuária da região de Araçatuba. Norteada pela periodização das ocupações hegemônicas no espaço agrícola regional, ponderou-se a trama apresentada a partir da análise das anexações dos sistemas de objetos superiores que alicerçaram no tempo diferentes divisões territoriais da produção e do trabalho. Café, algodão, pecuária bovina de corte e cana-de-açúcar configuraram ciclos de ocupações que se caracterizaram enquanto circuitos espaciais dominantes da agropecuária na região de Araçatuba. Usuárias da maioria das áreas agricultáveis do oeste paulista, a pecuária bovina de corte e a lavoura canavieira conformaram nas últimas décadas uma apropriação fundiária definida como sistema cana-boi. Em coexistência com essas ocupações hegemônicas, outras culturas alimentares atuaram produtivamente para o abastecimento prioritário do mercado interno local, regional e nacional. Dispostas em níveis diferenciados de tecnificação, capitalização e organizacional, essas atividades agropecuárias se fazem presentes na horizontalidade do território usado em circuitos espaciais de hegemonia complementar e subalternos. Característica do abastecimento de alimentos in natura nas regiões é a maioria do consumido ter origem distante. Resultado da divisão territorial da produção das diferentes culturas alimentares no espaço geográfico e do acúmulo de conhecimento técnico-organizacional dos produtores nas regiões agropecuárias, cada alimento possui predominantemente circuitos originários concentrados em pontos e manchas do território dados às especializações produtivas no mercado capitalista. Contudo, na manutenção de técnicas rudimentares sobrevive e se reproduz (nos interstícios das novas modernidades) racionalidades autóctones que persistem no oferecimento de produtos tradicionais da cultura regional. Para o período atual, apresenta-se nessa pesquisa a manifestação dessa multiterritorialidade vigente no espaço geográfico da região de Araçatuba. / This research analyzes the formation of the socio-spatial agriculture of Araçatuba / Sao Paolo / Brazil. Guided by the timeline of the hegemonic occupations in the regional agriculture space, weighed up the plot presented from the analysis annexations of upper objects that underpinned systems in different time territorial divisions of production and labor. Coffee, cotton, beef cattle and sugarcane configured cycles of occupations that were characterized as dominant spatial circuits of agriculture in Araçatuba. Users of most agricultural areas of Western Sao Paolo State, the beef cattle and sugarcane farming conformed in recent decades a land ownership defined as cane-ox system. In coexistence with these hegemonic occupations, other food crops worked productively for the priority supply of local, regional and national domestic market. Arranged in different levels of technological improvement, and organizational capitalizing, these agricultural activities are present in the horizontality of the used territory in spatial circuits complementary hegemony and subaltern. Characteristic of food supply in nature in the regions is the most distant source be consumed. Result of the territorial division of production of different food cultures in geographic space and the accumulation of technical-organizational knowledge producers in agricultural regions, each food has predominantly concentrated circuits originating in spots and stains the territory given to productive specializations in the capitalist market. However, in maintenance survives and reproduces rudimentary techniques (in the interstices of new modernities) autochthonous rationalities that persist in offering traditional products of regional culture. For the current period, is presented in this research the current manifestation of this multiterritoriality geographic space of Araçatuba.
42

Digestibilidade de nutrientes e parâmetros ruminais e sanguíneos de novilhos nelore alimentados com fontes protéicas e energéticas com diferentes degradabilidades ruminais. / Protein and starch sources varying in rumen degradability on nutrient digestibilities, ruminal and blood parameters of nelore steers.

Gabarra, Paola Ranzani 27 December 2001 (has links)
Foram utilizados 4 novilhos Nelore, pesando ao redor de 300 Kg, canulados no rúmen e duodeno, em um delineamento em Quadrado Latino 4x4, com o objetivo de se testar a possibilidade de melhor sincronização da degradação ruminal de fontes energéticas e protéicas, através da utilização de 2 formas de processamento de milho (moagem fina (1,5mm) x floculação (300g/l) e 2 fontes protéicas (farelo de soja x uréia). As dietas continham 13% de feno de gramínea tropical e 87% de concentrado, resultando em valores de PB ao redor de 13% e 83% de NDT. A floculação do milho resultou em menor concentração de amido no conteúdo duodenal, sugerindo uma maior degradação deste no rúmen, o que explica a redução de N-NH3 (P<0,01), de pH (P<0,15) e o aumento de C3 (P<0,01) no fluido ruminal. A concentração de uréia plasmática também foi reduzida com a floculação do milho em comparação com a moagem fina. O provável aumento da degradação ruminal do amido através da floculação do milho, resultou em aumento significativo (P<0,01) da digestibilidade deste nutriente no trato digestivo total, com um incremento ao redor de 10 unidades percentuais (89,22 x 98,90%) em comparação com a moagem fina. Entretanto, a digestibilidade da MS no trato digestivo total não foi aumentada (P>0,05) com a floculação do milho, provavelmente devido à redução (P<0,01) da digestibilidade do FDN. A substituição do farelo de soja por uréia não afetou (P>0,05) a fermentação ruminal, nem o consumo e a digestão de nutrientes no trato digestivo total. / Four Nelore steers, cannulated in the duodenum and in the rumen, averaging 300 kg of live weight, were used in a 4x4 Latin Square design, to test the improvement of ruminal synchronization of starch and protein degradation. Two methods of corn processing (fine grinding (1,5mm) vs steam flaking (300g/l)) and 2 protein sources (soybean meal vs urea) were compared in a 2x2 factorial arrangement. The diets contained 13% of tropical grass hay and 87% of concentrate, averaging 13% CP and 83% TDN. Steam flaking of corn decreased (P<0,01) starch concentration in duodenal digesta, suggesting a higher ruminal degradation of this nutrient. This would explain the actual decrease in ruminal N-NH3 (P<0,01) and pH (P<0,15) and the increase in molar concentration of ruminal C3 (P<0,01). PUN concentration was decreased (P<0,01) by steam flaking of corn compared to fine grinding. The probable increase of starch degraded in the rumen and post rumen, due to steam flaking, increased (P<0,01) digestibility of this nutrient in the total tract (89,22 x 98,90%), compared to fine grinding. However, the total tract DM digestibility was not increased (P>0,05) by steam flaking, probably due to the decrease (P<0,01) in NDF digestibility. The replacement of soybean meal by urea had no effect (P>0,05) on ruminal fermentation and on intake and total tract digestion of nutrients.
43

Pump Displacement Control in Steering On-Highway Commercial Vehicles

Amine Nhila (6194160) 10 January 2019 (has links)
<div>Due to recent advances in sensor technology and the exponential increase in computation power of electronic control units (ECUs) along with their increasing affordability, active safety and vehicle automation have become major trends in the commercial vehicle industry. New regulations for increased safety are also a major driver behind the industry's increased interest in that topic. As a result, being a crucial part of vehicle automation, steering systems had to be adapted to enable Active Steering. Consequently, commercial vehicle steering designers introduced the concept of torque and angle overlay using an electric motor in series with the conventional hydraulic steering system. However, despite the fact that these systems are becoming more prevalent in the market, they still suffer from inefficiencies intrinsic to the conventional hydraulic steering system still being used. These inefficiencies are a result of</div><div>flow metering losses due to the use of control valves to regulate the pump flow output, as well as inside the steering gear with the use control valves to build assistance pressure.</div><div><br></div><div><div>In this research project, we investigate the potential use of the proven pump Displacement Control (DC) technology in steering on-highway commercial vehicles. DC pumps have been shown to signicantly improve system efficiency as they allow the removal of control valves typically used to regulate </div><div>ow [1]. Instead, the displacement of the pump can be directly controlled to vary the pump's flow rate and direction,</div><div>and thus eliminating throttling losses. The DC technology has been successfully used in a steer-by-wire conguration for an articulated frame steering vehicle and has been shown to signicantly improve efficiency and productivity, as well as result in a reduction in fuel consumption [2].</div></div><div><br></div><div><div>In this work, we propose a steer-by-wire system, using DC pump technology, for on-highway commercial vehicles, and present the dierent possible congurations in which it can be implemented. Moreover, the benets and drawbacks of the steer-by-wire system are researched and identied. Subsequently, the system is designed and validated in simulation, on laboratory test setup, as well as on a test vehicle to prove its feasibility.</div></div><div><br></div><div><div>Chief among the drawbacks of the steer-by-wire system is potential failures that can lead to the complete loss of the steering function of the vehicle. As a result, different possible fail-safe mechanisms are researched from which the most suitable ones are proposed to allow the steer-by-wire system to fail safely. Moreover, two of the proposed fail-safe mechanism are implemented onto the test vehicle to prove and validate their feasibility.</div></div><div><br></div><div><div>Furthermore, an alternative way of using displacement controlled pumps for active steering is be proposed. For this concept, we investigate the possibility of actively controlling the driver's steering effort by varying the pump displacement while maintaining the mechanical link between the steering wheel and the road wheels. If successful, this method will allow for a more efficient way of providing steering assistance as it does away with the conventional control valves used to build pressure and regulate pump flow, and thus eliminating throttling losses. This method has also the advantage of having an intrinsic fail-safe mechanism with manual steering being always possible should the hydraulic or electric systems fail.</div></div>
44

Aveia branca e/ou casca de soja na dieta de bovinos alimentados com ou sem volumoso / White oat and/or soybean hull on the diet of bovines fed with or without roughage

Weise, Matheus Smidt 29 February 2016 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The aim of this work was to study the use of whole dry white oat grain (Avena sativa), soybean hulls (Glycine max L.), and the mixture of these ingredients (1:1), provided in two ways: with or without a roughage source on the diet. Sixty- eight male castrated steers, Charolais x Nelore crossbred, with initial average age of 20 months were used, distributed in a factorial scheme 3 x 2, with three energetic sources on the concentrate (white oat grain; soybean hulls and the mixture of these ingredients) and two ways of provision (with or without roughage). The roughage used was sorghum silage (Sorghum bicolor (L.) Moench), with roughage: concentrate of 50:50, based on DM. The ingestive behavior characteristics and the animal's performance response were measured and compared. The final weights of the steers did not differ statistically. The daily average gain of the mixture source (1.167 kg) was superior (P<0.05) to the soybean hulls (0.940 kg), being the oat grain intermediate (1.061 kg). It was observed higher (P<0.05) intake of dry matter and neutral and acid detergent fiber on the diets that contained roughage. Animals fed without roughage presented in the average better (P<0.05) feed conversion (6.291 kg) in relation to the animals fed with roughage (8.578 kg). Independently of the energetic source tested, steers fed with roughage remained more time (P<0.05) eating (4.23 h) and ruminating (7.88 h), compared to the ones fed without roughage (2.68 and 3.52 h, respectively). Steers fed with the energetic sources of oat grain and mixture, were more efficient in the dry matter intake (DM) when fed without roughage. On the average, steers fed without roughage were more efficient in the intake of neutral detergent fiber (NDF) and more efficient in the rumination of NDF. Steers fed with or without roughage presented difference (P<0.05) for the total chewing time (13.13 and 6.19h), for the number of ruminal bolus per day (502 and 184), and for the number of rumination chews (30,774 and 11,637, respectively). Steers from the soybean hulls energetic source chewed a few (P<0.05) number of times per ruminal bolus when fed without roughage (41.63), compared to the ones fed with roughage (62.66). / Objetivou-se neste trabalho, estudar a utilização do grão de aveia branca (Avena sativa) na forma inteiro seco, e a casca do grão de soja (Glycine max L.), e a mistura desses ingredientes (1:1), fornecidos de duas formas: com ou sem a fonte de volumoso na dieta. Foram utilizados 68 novilhos cruzas Charolês x Nelore, machos castrados, com idade média inicial de 20 meses, distribuídos em um esquema fatorial 3 x 2, com três fontes energéticas no concentrado (grão de aveia branca; casca do grão de soja e a mistura desses ingredientes) e duas formas de fornecimento (com ou sem volumoso). O volumoso utilizado foi silagem de sorgo (Sorghum bicolor (L.) Moench), com uma relação volumoso:concentrado de 50:50, com base na MS. Foram mensuradas e comparadas as características do comportamento ingestivo e respostas de desempenho dos animais. Os pesos finais dos novilhos não diferiram estatisticamente. O ganho médio diário da fonte energética Mistura (1,167 kg) foi superior (P<0,05) a Casca de Soja (0,940 kg), sendo Grão de Aveia intermediária (1,061 kg). Observou-se maiores (P<0,05) consumos de matéria seca e fibra em detergente neutro e ácido nas dietas que apresentavam volumoso. Animais alimentados sem volumoso apresentaram melhor (P<0,05) conversão alimentar (6,291 kg) em relação aos animais alimentados com volumoso (8,578 kg). Independente da fonte energética testada, novilhos alimentados com volumoso desprenderam mais tempo (P<0,05) se alimentando (4,23 h) e ruminando (7,88 h), comparados aos sem volumoso (2,68 e 3,52 h, respectivamente). Novilhos alimentados com as fontes energéticas Grão de Aveia e Mistura foram mais eficientes nos consumos de matéria seca (MS) quando alimentados sem volumoso. Na média os novilhos alimentados sem volumoso foram mais eficientes no consumo de fibra em detergente neutro (FDN), e mais eficientes na ruminação da FDN. Novilhos alimentados com e sem volumoso apresentaram diferença (P<0,05) para o tempo de mastigação total (13,13 e 6,19h), no número de bolos ruminais por dia (502 e 184), e no número de mastigadas merícicas (30.774 e 11.637, respectivamente). Novilhos da fonte energética Casca de Soja mastigam em menor (P<0,05) número de vezes por bolo ruminal quando alimentados sem volumoso (41,63), em comparação aos alimentados com volumoso (62,66).
45

Da formação socioespacial à diferenciação dos circuitos espaciais agropecuários na região de Araçatuba (SP) / From the sociospacial training to the differentiation of circuits in agricultural region of Araçatuba (SP)

Danton Leonel de Camargo Bini 03 March 2015 (has links)
A presente pesquisa analisa a formação socioespacial agropecuária da região de Araçatuba. Norteada pela periodização das ocupações hegemônicas no espaço agrícola regional, ponderou-se a trama apresentada a partir da análise das anexações dos sistemas de objetos superiores que alicerçaram no tempo diferentes divisões territoriais da produção e do trabalho. Café, algodão, pecuária bovina de corte e cana-de-açúcar configuraram ciclos de ocupações que se caracterizaram enquanto circuitos espaciais dominantes da agropecuária na região de Araçatuba. Usuárias da maioria das áreas agricultáveis do oeste paulista, a pecuária bovina de corte e a lavoura canavieira conformaram nas últimas décadas uma apropriação fundiária definida como sistema cana-boi. Em coexistência com essas ocupações hegemônicas, outras culturas alimentares atuaram produtivamente para o abastecimento prioritário do mercado interno local, regional e nacional. Dispostas em níveis diferenciados de tecnificação, capitalização e organizacional, essas atividades agropecuárias se fazem presentes na horizontalidade do território usado em circuitos espaciais de hegemonia complementar e subalternos. Característica do abastecimento de alimentos in natura nas regiões é a maioria do consumido ter origem distante. Resultado da divisão territorial da produção das diferentes culturas alimentares no espaço geográfico e do acúmulo de conhecimento técnico-organizacional dos produtores nas regiões agropecuárias, cada alimento possui predominantemente circuitos originários concentrados em pontos e manchas do território dados às especializações produtivas no mercado capitalista. Contudo, na manutenção de técnicas rudimentares sobrevive e se reproduz (nos interstícios das novas modernidades) racionalidades autóctones que persistem no oferecimento de produtos tradicionais da cultura regional. Para o período atual, apresenta-se nessa pesquisa a manifestação dessa multiterritorialidade vigente no espaço geográfico da região de Araçatuba. / This research analyzes the formation of the socio-spatial agriculture of Araçatuba / Sao Paolo / Brazil. Guided by the timeline of the hegemonic occupations in the regional agriculture space, weighed up the plot presented from the analysis annexations of upper objects that underpinned systems in different time territorial divisions of production and labor. Coffee, cotton, beef cattle and sugarcane configured cycles of occupations that were characterized as dominant spatial circuits of agriculture in Araçatuba. Users of most agricultural areas of Western Sao Paolo State, the beef cattle and sugarcane farming conformed in recent decades a land ownership defined as cane-ox system. In coexistence with these hegemonic occupations, other food crops worked productively for the priority supply of local, regional and national domestic market. Arranged in different levels of technological improvement, and organizational capitalizing, these agricultural activities are present in the horizontality of the used territory in spatial circuits complementary hegemony and subaltern. Characteristic of food supply in nature in the regions is the most distant source be consumed. Result of the territorial division of production of different food cultures in geographic space and the accumulation of technical-organizational knowledge producers in agricultural regions, each food has predominantly concentrated circuits originating in spots and stains the territory given to productive specializations in the capitalist market. However, in maintenance survives and reproduces rudimentary techniques (in the interstices of new modernities) autochthonous rationalities that persist in offering traditional products of regional culture. For the current period, is presented in this research the current manifestation of this multiterritoriality geographic space of Araçatuba.
46

Interface Design for Driver Operated Control Systems

Azamfirei, Victor, Preciado Navarro, Luis Donaldo January 2017 (has links)
No description available.
47

Digestibilidade de nutrientes e parâmetros ruminais e sanguíneos de novilhos nelore alimentados com fontes protéicas e energéticas com diferentes degradabilidades ruminais. / Protein and starch sources varying in rumen degradability on nutrient digestibilities, ruminal and blood parameters of nelore steers.

Paola Ranzani Gabarra 27 December 2001 (has links)
Foram utilizados 4 novilhos Nelore, pesando ao redor de 300 Kg, canulados no rúmen e duodeno, em um delineamento em Quadrado Latino 4x4, com o objetivo de se testar a possibilidade de melhor sincronização da degradação ruminal de fontes energéticas e protéicas, através da utilização de 2 formas de processamento de milho (moagem fina (1,5mm) x floculação (300g/l) e 2 fontes protéicas (farelo de soja x uréia). As dietas continham 13% de feno de gramínea tropical e 87% de concentrado, resultando em valores de PB ao redor de 13% e 83% de NDT. A floculação do milho resultou em menor concentração de amido no conteúdo duodenal, sugerindo uma maior degradação deste no rúmen, o que explica a redução de N-NH3 (P<0,01), de pH (P<0,15) e o aumento de C3 (P<0,01) no fluido ruminal. A concentração de uréia plasmática também foi reduzida com a floculação do milho em comparação com a moagem fina. O provável aumento da degradação ruminal do amido através da floculação do milho, resultou em aumento significativo (P<0,01) da digestibilidade deste nutriente no trato digestivo total, com um incremento ao redor de 10 unidades percentuais (89,22 x 98,90%) em comparação com a moagem fina. Entretanto, a digestibilidade da MS no trato digestivo total não foi aumentada (P>0,05) com a floculação do milho, provavelmente devido à redução (P<0,01) da digestibilidade do FDN. A substituição do farelo de soja por uréia não afetou (P>0,05) a fermentação ruminal, nem o consumo e a digestão de nutrientes no trato digestivo total. / Four Nelore steers, cannulated in the duodenum and in the rumen, averaging 300 kg of live weight, were used in a 4x4 Latin Square design, to test the improvement of ruminal synchronization of starch and protein degradation. Two methods of corn processing (fine grinding (1,5mm) vs steam flaking (300g/l)) and 2 protein sources (soybean meal vs urea) were compared in a 2x2 factorial arrangement. The diets contained 13% of tropical grass hay and 87% of concentrate, averaging 13% CP and 83% TDN. Steam flaking of corn decreased (P<0,01) starch concentration in duodenal digesta, suggesting a higher ruminal degradation of this nutrient. This would explain the actual decrease in ruminal N-NH3 (P<0,01) and pH (P<0,15) and the increase in molar concentration of ruminal C3 (P<0,01). PUN concentration was decreased (P<0,01) by steam flaking of corn compared to fine grinding. The probable increase of starch degraded in the rumen and post rumen, due to steam flaking, increased (P<0,01) digestibility of this nutrient in the total tract (89,22 x 98,90%), compared to fine grinding. However, the total tract DM digestibility was not increased (P>0,05) by steam flaking, probably due to the decrease (P<0,01) in NDF digestibility. The replacement of soybean meal by urea had no effect (P>0,05) on ruminal fermentation and on intake and total tract digestion of nutrients.
48

Road Feedback in a Steer-by-Wire System for a Passenger Car : enhancing the feeling of being connected

Finne, Alice, Ström, Louise January 2022 (has links)
Road feedback is an essential part of the driving experience, representing a connection betweenthe driver and the vehicle motion. Road feedback in a steer-by-wire system must berecreated and transferred to the driver through a feedback motor mounted on the steeringwheel. This project aimed to implement a function in the feedback motor control with thepurpose of giving the driver road feedback. The function should enhance the drivers trustand confidence in the steering system. Specifically, the function should provide the driverwith a feeling of being connected to the vehicle. A pre-study on the subject of steering feel was made as well as an interview study, whichresulted in a list of hypotheses. The hypotheses became a basis for generating conceptideas, together with measurement data of vehicle network signals for different drivingscenarios. Two different functions were then modelled and implemented in MathWorksSimulink. Function 1 models force components acting on the front road wheels in longitudinal,lateral and vertical direction. The forces result in a torque contribution fromeach dimension that acts around the steering axis and represents a reaction in the steeringsystem due to road disturbances. The torque is then translated to a steering wheel torque.Function 2 strives to capture road surface roughness through the high frequency informationin the steering rack motor torque. Three different road surfaces were studied; smoothasphalt, rough asphalt and gravel road. A test rig was used in order to verify the behaviour of the functions. The final step of theproject was to implement the functions in a test vehicle, where they could be further tunedand evaluated. The force component models of Function 1 captured different types of roadfeedback which were evaluated separately by timing, authenticity and desirability. Theresult of this evaluation was positive considering them separately. When the models werecombined it resulted in an unwanted behaviour. Function 2 gave torque feedback that feltauthentic and natural, especially for the gravel road case. However, it was more difficult todistinguish different asphalt types. The conclusion was that neither Function 1 nor 2 couldbe approved as finished functions, however both are considered as interesting concepts forfurther development. Fully steer-by-wire steering transmissions have now been approved for usage. This meansthat one of the remaining challenges for implementing steer-by-wire cars on today’s marketis the subjective views from the customers. Function 1 and 2 could be a way to providethe drivers with trust towards the steering, and at the same time, enhance the drivingexperience. / <p>The presentation was held at ACAS at Linköping University. The presentation included a summary and learnings from the project. A short demonstration was performed using a test-rig consisting of a steering wheel, a feedback motor and a control unit. </p>
49

Electrically powered manoeuvring of water jets / Elektrisk manövrering av vattenjetaggregat

Engström, Joel January 2021 (has links)
A shift towards electric and hybrid propulsion within the marine sector create new challenges for conventional water jet units manoeuvred by hydraulic systems. The high efficiency in high speed water jet crafts benefit from being powered by electricity but will be compromised by constantly running hydraulic pumps, draining available electric capacity on-board. Wear and tear on hydraulic components are also an environmental contamination hazard, due to high pressure oil and exposed cylinder rods. However, conventional hydraulic power packs with subsystems to manoeuvre water jet unit is a well proven and reliable marine application.Steer-by-wire is not an uncommon subject, as it is frequently used in several industries such as aviation, automotive and offshore. The purpose of the study is to prepare a concept design proposal with CAD-models and drawings of electrically powered manoeuvring system for Marine Jet Powers DRB 750 steering units. The study did a literature study on the topic and qualitative research to fulfil the purpose. A generic product and concept development is conducted and computer aided design is done to present proposed prototype design.Results from the research gave 4 commercially available electrical actuators, all with significantly different functionality from each other resulting in 4 different concepts and thereof 1 prototype proposal integrated in the waterjet unit according to DNV standards.The selected concept in the study will need some further manufacturing configuration and optimisation for a full installation and working prototype. / Ett skifte mot elektisk och hybriddrift inom marina fartyg och framdrivningssystem skapar nya utmaningar och möjligheter, även så för höghastighetsfartyg där vattenjet har en fördel i sin karaktäristiska höga effektivitet. Idag manövreras vattenjetsaggregat med hjälp av hydraulik, som många gånger drivs med framdrivningsmaskineriet och/eller med en elektisk pump. Dessa system blir en energitjuv i en elektrisk eller hybridlösning för framdrivningen och så saknar det en naturlig lösning på hur en hydraulisk pump ska drivas. Slitage och skador på hydrauliska system kan även leda till miljöfarliga utsläpp av hydraulolja. Framför allt då det handlar om höga hydrauliska tryck och bland annat kolvstänger som är utsatta för påfrestningar från fartygens yttre miljö. Dock är hydrauliska system väl beprövade och pålitliga i marina miljöer.Styrning med hjälp av elkraft är inget som är nytt, även kallat Steer-by-wire, det har gjorts och används inom många områden så som flygplans-, bil- och offshoreindustrin. Syftet med studien är att skapa ett prototypförslag för elektisk manövrering av Marine Jet Powers vattenjetaggregat DRB 750. För att uppnå detta har en litteraturstudie genomförts och kvalitativ forskning för att samla information och få förståelse för ämnet. En generisk product- och konceptutveckling har använts med hjälp av datorstödd konstruktion för att presentera ett prototypförslag.Det har resulterat i 4 koncept med integrerade lösningar från olika tillverkare, som alla skiljer från varandra i funktionalitet och skulle kunna användas på ett sätt för att uppnå målet. Varav ett koncept som valdes, det vidareutvecklades till ett prototypförslag med skruvförband i vattenjetaggregatet och som även sågs till att uppfylla DNV:s standarder och regler. Det valda konceptet behöver vidare utveckling, integrering och optimering för att kunna installeras och testas i fungerande prototyp.
50

National Beef Quality Audit - 2011: Survey of Instrument Grading Assessments of Beef Carcass Characteristics

Gray, Gatlan 1989- 14 March 2013 (has links)
The instrument grading assessments for the NBQA-2011 evaluated seasonal trends of beef carcass quality and yield attributes over the course of the year. One week of instrument grading data—HCW, gender, USDA QG, and YG factors—were collected every other month (n = 2,427,074 carcasses) over a 13-month period (November 2010 through November 2011) from four beef processing corporations, encompassing 17 federally inspected beef processing facilities, to create an overview of carcass quality and yield attributes and trends from carcasses representing approximately 8.5% of the U.S. fed steer and heifer population. Mean yield traits were: YG (2.86), HCW (371.3 kg), FT (1.19 cm.), and LM area (88.39 cm^2). The YG distribution was YG 1 (15.7%), YG 2 (41.0%), YG 3 (33.8%), YG 4 (8.5%), and YG 5 (0.9%). Distribution of HCW was <272.2 kg (1.6%), 272.2 kg to 453.6 kg (95.1%), ≥453.6 kg (3.3%). Monthly HCW means were: November 2010 (381.3 kg), January 2011 (375.9 kg), March 2011 (366.2 kg), May 2011 (357.9 kg), July 2011 (372.54 kg), September 2011 (376.1 kg), and November 2011 (373.5 kg). The mean FT for each month was November 2010 (1.30 cm), January 2011 (1.22 cm), March 2011 (1.17 cm), May 2011 (1.12 cm), July 2011 (1.19 cm), September 2011 (1.22 cm), and November 2011 (1.22 cm). The mean marbling score was Small49. USDA QG distribution was Prime (2.7%), Top Choice (22.9%), Commodity Choice (38.6%), and Select (31.5%). Interestingly, from November to May, seasonal decreases (P < 0.001) in HCW and FT were accompanied by increases (P < 0.001) in marbling. These data present the opportunity to further investigate the entire array of factors that determine the value of beef. Datasets utilizing the online collection of electronic data will likely be more commonly used when evaluating the U.S. fed steer and heifer population in future studies. These data indicate the wide array of carcasses produced by the beef cattle industry, and how the frequency of both YG and QG traits change from month-to-month.

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