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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.
871

Development and evaluation of ground and aerial robotic systems in commercial poultry houses

Parajuli, Pratik 06 August 2021 (has links) (PDF)
The live production sector of the poultry industry has a growing interest in robotics. Robotics have the possibility to monitor environmental conditions, assess bird welfare, and reduce labor for farm workers and owners. However, interactions of poultry with robotic systems in commercial poultry house environments is largely unknown. Therefore, the goal of this research was to assess the effect of ground and aerial robots on bird stress using avoidance distance (AD) and fleeing speed (FS) as indirect indicators. A low-cost, autonomous robot was also developed to aid in collecting data on environmental conditions in commercial broiler houses. AD and FS were measured for multiple breeds (broilers, brown hens, and white hens) at different bird ages. Poultry-robot AD was greater than poultry-human AD for both broilers and laying hens, indicating that birds tended to avoid the ground robot more than humans. However, birds did become accustomed to the ground robot as reflected by decreasing AD and FS over the trial periods. Aerial drones operated in a commercial broiler house were found to induce a larger AD and higher FS than a moveable sensor package attached to a fixed, overhead rail system. No significant difference was found in the performance of the low-cost, autonomous robot when tested on different substrates (hard tile and litter). However, some differences were found when the robot was operated at different speeds. Results from these studies have provided useful insight into the operation of ground and aerial robots in commercial poultry settings.
872

Sorption Characteristics of Veterinary Ionophore Antibiotics Monensin and Lasalocid and Soil Clay Constituents Kaolinite, Illite and Montmorillonite

Swan, Kathie Lanette January 2012 (has links)
No description available.
873

Responses of Rumen Microbes to Excess Carbohydrate

Hackmann, Timothy John 05 July 2013 (has links)
No description available.
874

Evolution of Influenza A Viruses in Exhibition Swine and Transmission to Humans, 2013-2015

Szablewski, Christine Marie 14 June 2018 (has links)
No description available.
875

Feasibility study: Biogas in Sonderborg

Lopes, Merwyn January 2009 (has links)
The purpose of this feasibility study has been to guide decision makers in the implementation of abiogas project for the region of Sønderborg, Denmark. The project has been part of Feasibility studies envisioned in the Master Plan for Sønderborg to go carbon neutral by 2029. The study tried to evolve abest alternative for the city and gives a ready document to refer all aspects of biogas. The intensive industrial farming in Sønderborg needs to evolve to compare favorably with the situationin other regions of Denmark. The interests of various stakeholders in the waste cycle should be alignedwith that of farming. Interesting developments in the Bioenergy space hold promise for farmers to usetheir capacities for additional or alternative livelihood in energy. The focus to promote biogas as part ofDanish energy strategy and multiply capacity over the next 3 years has attracted numerous biogas proposals all over Denmark. This study had started off with identifying and estimating very obvious substrate sources. At verymoderate assumptions the value of methane in these sources has been estimated at 9 million m3. Thispotential could easily be increased if economically feasible substrates like energy crops and algae areadded. The SWOT analysis of pig farming in the region brings out the perspectives of farming direction in the near future. The 5 scenarios developed help the decision maker understand the various aspects thatneed to be carefully considered when planning the plant. The best case scenario for the city would bethe energy mosaic scenario which would integrate the high tech focus of local industry, a renewable energy source and a showcase project to make the region stand out among the other regions focused inthe climate change debate. The technological system analysis should help decision makers understand the stakeholders and the various dimensions in biogas that although complicated are manageable. The business case approach to identify utilization of energy and its costs gives a clear picture on the need for using the energy in CHP.The present focus by potential investors on government subsidies to calculate profitability needs to be understood in the context of other similar plants accepting present subsidy levels and the societal benefits, which unfortunately cannot be valued in money terms. At the center of all this is the need for proper stakeholder management within a bound timeframe asidentified by the “Create acceptance process”. The various tools and data are all present in this study,that only need to be arranged and presented by the company eventually handling the strict Projectmanagement goals of this project. / <p>www.ima.kth.se</p>
876

[pt] DE UMA ERVA SÓ SE ENFARA O GADO: ECOLOGIA HISTÓRICA DE PASTAGENS NA MATA ATLÂNTICA / [en] ONLY ONE GRASS MAKES CATTLE SICK: HISTORICAL ECOLOGY OF PASTURES IN THE ATLANTIC FOREST

LUCAS SANTA CRUZ DE ASSIS BRASIL 13 November 2023 (has links)
[pt] O Vale do Paraíba recebeu no século XIX o empreendimento cafeeiro, profundo transformador das paisagens da região, que em menos de cem anos se esvaneceu da paisagem. Ao explorarmos as agências costumeiramente negligenciadas, novas possibilidades de análises sobre a ecologia histórica das áreas que resultaram do declínio cafeeiro emergem. Abordagens que consideram as relações multiespécies têm a oportunidade de revelar interações socioecológicas ocultadas pela historiografia,e (re) contar a história da paisagem. Assim, o objetivo geral desta tese foi compreender a distribuição de gramíneas africanas e os legados socioecológicos a elas associados na paisagem atual do vale em uma perspectiva temporal ampla. Para tanto foram utilizados levantamentos documentais iconográficos e textuais em acervos históricos em conjunção com a observação da paisagem em trabalhos de campo para aquisição de dados vegetacionais e de compactação do solo. Foram observadas relações entre pessoas negras e a prática de pecuária nas propriedades de plantation, assim como usos variados para gramíneas de origem africana nos registros históricos. A atividade econômica do tropeirismo produziu significativa mudança em áreas de difícil acesso da Serra do Mar, indicando a incrível necessidade de pastos distribuídos por rotas comerciais para que se efetivassem. A densidade aparente de pastagens e de locais que foram pastagens há no mínimo 30 anos mostram a heterogeneidade destes ambientes. Concluímos que as agências humanas e não humanas trazem perspectivas que podem auxiliar na explicitação da paisagem atual da região. / [en] In the nineteenth century, the Paraíba do Sul Valley received the coffee enterprise, a profound transformer of the region s landscapes, which in less than one hundred years has faded from the landscape. By exploring the usually neglected agencies, new possibilities for analyses of the historical ecology of these areas emerge. Approaches that consider multispecies relationships can reveal social-ecological interactions hidden by historiography and (re)tell the story of the landscape. Thus, the general objective of this thesis was to understand the distribution of African grasses and their associated social-ecological legacies in the current landscape of the valley from a broad temporal perspective. To this end, iconographic and textual documentary surveys in historical collections were used in conjunction with landscape observation in fieldwork to acquire vegetational and soil compaction data. Relations between Black people and the practice of cattle-raising on plantation properties were observed, as well as varied uses for grasses of African origin in the historical records. The economic activity of tropeirismo - the commercial trade made by free man in association with mules - produced a meaningful change in difficult access areas in the Serra da Bocaina, regional name for the larger Serra do Mar, indicating the dependence on pastures distributed by trade routes for their effect. Today, the apparent density of pastures and sites that were pastureland at least 30 years ago show the heterogeneity of environments in which ranching occurs or occurred, indicating multiple trajectories for land uses from grazing. We conclude that human and non-human agencies bring perspectives that can assist in explaining the current landscape of the region.
877

Water Resources in the Anthropocene / Assessing the impact of climate change on freshwater supply and the scope for adaptation in the livestock sector

Heinke, Jens 05 March 2021 (has links)
Der hydrologische Kreislauf versorgt die Menschheit mit Wasserressourcen, die für ihr Wohlergehen unabdingbar sind. Ziel dieser Arbeit ist es, das Verständnis über klimabedingte Veränderungen des hydrologischen Kreislaufs zu verbessern, wie diese die Verfügbarkeit von Wasserressourcen in der Zukunft beeinflussen und welche Möglichkeiten bestehen, den Druck auf die verfügbaren Wasserressourcen durch Verringerung des anthropogenen Wasserverbrauchs zu reduzieren. Diese Dissertation zeigt, dass der Klimawandel eine große Bedrohung für die Wasserversorgung der zukünftigen Bevölkerung darstellt. Durch Begrenzung des Anstiegs der globalen Mitteltemperatur auf 2 K oder sogar 1,5 K über das vorindustrielle Niveau können gravierende negative Auswirkungen auf die Wasserverfügbarkeit jedoch weitgehend vermieden werden. Dennoch wären einige Regionen wie der Mittelmeerraum "eher wahrscheinlich" von schwerwiegenden hydrologischen Veränderungen betroffen, und in großen Teilen der Welt könnten negative Auswirkungen auf die Wasserverfügbarkeit aufgrund der großen Unsicherheiten in den Projektionen nicht ausgeschlossen werden. Bei der Untersuchung der Nachfrageseite liegt der Schwerpunkt auf der Wassernutzung in der Tierproduktion. Diese Dissertation schätzt den gegenwärtigen Wasserverbrauch für die Produktion von Tierfutter auf 4666 km3/yr (44 % des gesamten landwirtschaftlichen Wasserverbrauchs). Große Verbesserungen der Wasserproduktivität können bei Schweinen und Geflügel durch Verbesserungen sowohl in der Futtermittelproduktion als auch in der Tierhaltung erzielt werden. Bei Wiederkäuern liegt das größte Potenzial in der Verbesserung der Tierhaltung. Allerdings geht eine effizientere Futterverwertung bei Wiederkäuern, die durch erhöhte Beigabe von Kraftfutter erzielt wird, mit einem erhöhten Wasserbedarf für die Produktion des Futters einher. Dadurch ist die Verbesserung der Wasserproduktivität bei Wiederkäuern begrenzt. / The hydrological cycle provides humanity with water resources that are essential for its well-being. The aim of this thesis is to advance the understanding of climate-related changes in the hydrological cycle, how they will affect the availability of water resources in the future, and what opportunities exist to reduce anthropogenic water use to lower the pressure on water resources. This thesis demonstrates that climate change is a large threat to freshwater supply for future populations. Limiting the increase in global mean temperature to 2 K or even 1.5 K above pre-industrial levels can mitigate most of the severe negative impacts on water resources. However, some regions such as the Mediterranean would still ‘more likely than not’ be affected by severe hydrological change, and in large parts of the world, negative impacts on water availability could not be ruled out due to the large uncertainties in the projections. On the demand side, the focus is on water use in the livestock sector. This thesis estimates that about 4666 km3/yr (44 % of total agricultural water use) are currently used for feed production for the livestock sector. Large improvements in livestock water productivity can be achieved for pigs and poultry by improvements in feed production and livestock rearing alike. For ruminants, the largest potential lies in improving livestock management. However, improving the feed use efficiency of ruminants through increased supplementation with forage crops comes at the cost of increased water requirements to produce the feed. This limits the potential for improving livestock water productivity in ruminant production.
878

Systems thinking methodology in researching the impacts of climate change on livestock industry: Policy paper

Nguyen, Quan Van, Nguyen, Nam Cao 14 November 2013 (has links)
The impacts of climate change on livestock production are complex problems, existing in the rela-tionship among this sector and others sectors such as environmental, social, economic and political systems. The complexity and dynamic of these impacts cannot be solved simply in isolation with the linear approach. A system thinking methodology is introduced in this paper to understand the impacts of climate change on livestock production, and identify effective interventions strategies to address this systemic problem. System thinking is a way of thinking about the world and relationships which has been developed far along way in the past. Today, systems thinking has become increasingly popular because it provides a \'new way of thinking\' to understand and manage complex problems, whether they rest within a local or global context. While four levels of thinking is a fundamental tool to identify systemic problems, Causal Loop Diagram (CLD) is a visual tool created by a computer program to illustrate the whole picture of climate change impacts. CLD consist of feedbacks for system, which help strategists identify appropriate intervention strategies in solving the systemic problem. / Ảnh hưởng của biến đổi khí hậu đến ngành chăn nuôi là một trong những vấn đề phức tạp, bởi mối quan hệ chặt chẽ có hệ thống của chúng với các lĩnh vực khác như môi trường, xã hội, kinh tế và chính trị. Những tác động phức tạp đa chiều này không thể giải quyết đơn thuần bằng các giải pháp mang tính đơn lẻ. Phương pháp tư duy hệ thống được giới thiệu trong bài này cho phép hiểu đầy đủ, có hệ thống các tác động của biến đổi khí hậu đến ngành chăn nuôi, đồng thời xác định được những giải pháp chiến lược phù hợp để giải quyết vấn đề mang tính hệ thống này. Tư duy hệ thống là cách tư duy và tiếp cận với sự vật, hiện tượng khách quan, và các mối quan hệ của chúng, phương pháp này đã được nghiên cứu và phát triển từ xa xưa. Ngày nay, tư duy hệ thống đang được ứng dụng phổ biến và rộng rãi hơn trong các nghiên cứu phát triển bền vững vì phương pháp này cung cấp một “tư duy mới” để hiểu và quản lý được các vấn đề phức tạp, dù chúng ở qui mô địa phương hay trên phạm vi toàn cầu. Trong đó, bốn cấp bậc của tư duy là công cụ cơ bản để nhận biết các vấn đề phức tạp, và sơ đồ các vòng tròn tác động (CLD) là công cụ trực quan được xây dựng bằng phần mềm máy tính để chỉ ra bức tranh toàn cảnh các tác động của biến đổi khí hậu. Các vòng tròn tác động này phản ánh các diễn biến thực tế và các thông tin giúp cho việc xác định các giải pháp chiến lược.
879

Selecting And Utilizing Recreational Reading Materials For The Middle School Classroom

Jones, Danielle N. 05 April 2009 (has links)
No description available.
880

Towards the Horsewoman: Performing Femininity in the American Horse Training and Riding Arenas

Ellison, Season M. 23 November 2009 (has links)
No description available.

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