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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.
81

Analýza obchodu s vybranými druhy z řádů Coraciiformes, Musophagiformes, Columbiformes a Piciformes / Analysis of Trade with selected species of Coraciiformes, Musophagiformes, Columbiformes and Piciformes

ZÁHOROVÁ, Lucie January 2018 (has links)
International trade in fauna and flora is curently considered as one of the greatest threats to populations of many wildlife species. According to available information, some species are declining mainly due to persecution by people for meat or for trade. Illegal trade is increasing as well. Its yearly turnover is estimated to be in the order of billions of US dollars. This diploma theses analyzes the international trade with selected bird species under the CITES Convention - Asian hornbills, African turacos, South American tukans and arassari, and pigeons and doves during the period from 1990 till 2015. Although the CITES Convention has proven to contribute to protecting biodiversity and protecting endangered species by monitoring and regulating the trade with them, it has its limitations and shortcomings. These are described in this diploma thesis on the example of some specific cases.
82

Consórcio de milho com adubos verdes e manejo da adubação nitrogenada no cultivo de feijão em sucessão no sistema integração lavoura-pecuária no cerrado / Nitrogen fertilization management in bean cultivated after maize-legumes intercropping in the Crop-Livestock Integration system in Brazilian Savannah

Priscila de Oliveira 29 June 2010 (has links)
Foram realizados dez experimentos envolvendo as culturas de feijão e milho consorciado com leguminosas e/ou Brachiaria brizantha, nas safras de verão de 2008/2009, inverno de 2009 e verão de 2009/2010, em dois municípios de estado de Goiás (GO). Em Ipameri-GO, a área foi cultivada com soja por vários anos e milho consorciado com B. brizantha na safra que precedeu a implantação dos experimentos. Em Santo Antônio de Goiás-GO, a área é mantida com a rotação de milho e soja com a forrageira B. brizantha, em esquema trienal. Os principais objetivos desses estudos foram avaliar: (i) a viabilidade do consórcio de milho com leguminosas, (ii) a resposta do feijoeiro cultivado em sucessão e (iii) o manejo do N nessas culturas. Foi constatado que em solos com média a alta fertilidade química, como os utilizados na experimentação, os consórcios de milho com B. brizantha ou com guandu-anão (Canajus cajan) ou crotalária (Crotalaria spectabilis) não interferiram na produtividade de grãos de milho na presença de N em cobertura, exceto no experimento conduzido em Santo Antônio de Goiás-GO, no qual a crotalária reduziu significativamente a produtividade do milho. Também, em ambos os locais, no consórcio simultâneo ou defasado de milho com crotalária ou guandu-anão não ocorreu liberação de nitrogênio (N) das leguminosas para o milho, medido pela produtividade de grãos, durante o ciclo das espécies. Já nos consórcios em que a B. brizantha foi mantida sem dessecação nas entrelinhas do milho, denominado de dessecação parcial, ocorreu decréscimo significativo na produtividade do milho, em relação ao cultivo em área totalmente dessecada. A análise de crescimento revelou maiores índice de área foliar (IAF) e acúmulo de massa de matéria seca da parte aérea (MSPA) para o guandu em monocultivo, sendo que para a crotalária cultivada na linha do milho, tanto o IAF quanto a MSPA aproximaram-se dos valores referentes ao monocultivo. As curvas de crescimento do milho revelaram a superioridade do cultivo com 90.kg.ha-1 de N tanto no IAF quanto na MSPA, quando comparado ao cultivo consorciado com leguminosas. No caso de Santo Antônio de Goiás-GO, na rotação trienal envolvendo espécies graníferas e forrageiras, registrou-se um acentuado aporte de N no solo, sendo obtidas altas produtividades de feijão cultivado em sucessão à pastagem, sem a aplicação de N mineral, ocorrendo, porém, aumento significativo na produtividade do feijoeiro nos tratamentos de palhadas que continham leguminosas. A aplicação de N mineral imediatamente antes da semeadura ou no estádio de plântulas do feijão e do milho teve efeito semelhante nas suas produtividades em relação à aplicação tradicional, ou seja, algumas semanas após a emergência dessas espécies. A aplicação de N mineral foi mais eficiente no aumento da produtividade de feijão irrigado quando feita próximo às fileiras de plantas ou quando o N foi incorporado mecanicamente no solo, comparados à aplicação a lanço. / Ten experiments were performed involving common beans and maize intercropped with legumes and/or Brachiaria brizantha, in the summer crops of 2008/2009, 2009 winter and summer of 2009/2010 in two municipalities in the Goiás (GO) state, Brazil. In Ipameri- GO, the area was planted with soybeans for several years and corn associated with B. brizantha in crop preceding the experiments. In Santo Antônio de Goiás-GO, the area is maintained with corn or soybean rotation with B. brizantha, in a three-year scheme. The main objectives of these studies were to evaluate the feasibility of intercropping maize with legumes and the response of common bean after it, in no-tillage system, on the mulching straws provided by the cultivation of maize intercropped with forage legumes and grasses and to study the management of nitrogen (N) in these two crops. It was found that in soils with medium to high chemical fertility, such as those used in the experiments, the intercropping of corn and B. brizantha or pigeonpea (Canajus cajan) and sunn hemp (Crotalaria spectabilis) had any influence on grain yield of maize in the presence of mineral N, except in the experiment conducted in Santo Antonio de Goiás-GO, where the sunn hemp significantly reduced corn productivity. Also, in both locations, simultaneous or lagged consortium of pigeonpea or sunn hemp with maize, there was no release of N from legumes to maize, as measured by grain productivity, during the cycle of the species. However, in the consortia in which B. brizantha is maintained without drying between the maize lines, called partial desiccation, there was a significant decrease in the yield of corn in relation to the totally desiccated area. The growth analysis showed higher leaf area index (LAI) and total dry matter accumulation (TDM) for pigeonpea grown in single system, but for sunn hemp cultivated in the corn rows, both LAI and TDM approached to its single cropping, confirming its competitiveness with corn in the intercropping system. Growth curves also showed the superiority of the corn crop with 90 kg N ha-1 in both LAI and TDM, compared to intercropping with legumes. In the case of Santo Antônio de Goiás-GO the three-year rotation involving grain species and grass forages caused an intake of N in the soil, and high yields of beans grown in rotation with pasture were obtained, without the application of mineral N, occurring, though, significant increase in grain yield in the treatments of straws containing legumes. The application of mineral N immediately before sowing or at the seedling stage of beans and corn had a similar effect on their productivity compared to traditional application, a few weeks after the emergence of these species. The application of mineral N was more efficient in increasing the productivity of beans when applied on the soil surface near the plants rows and in cases where the fertilizer was mechanically incorporated into the soil, comparing to surface-broadcasting.
83

Conceptual Design of a South Pole Carrier Pigeon UAV

Dlima, Kendrick M 01 June 2020 (has links)
Currently, the South Pole has a large data problem. It is estimated that 1.2 TB of data is being produced every day, but less than 500 GB of that data is being uploaded via aging satellites to researchers in other parts of the world. This requires those at the South Pole to analyze the data and carefully select the parts to send, possibly missing out on vital scientific information. The South Pole Carrier Pigeon will look to bridge this data gap. The Carrier Pigeon will be a small unmanned aerial vehicle that will carry a 30 TB solid-state hard drive from the South Pole to various destinations in the Southern Hemisphere, but it has been designed to y to Christchurch, New Zealand. This 87 lb. UAV will be able to y 3,650 nmi. up to 25,000 ft., using a 5.7 hp. engine. It will feature an de-icing system on the leading edge of its 8 ft. span wing to allow it to y through cold, moist climates. It will have a 39 in. long fuselage with a tail boom of 33 in. The aircraft has been designed to be made out of composites, thus reducing both the weight of the aircraft as well as its drag. It has been designed to come apart in order to be shipped successfully to the South Pole. There, it will be assembled and launched via a custom pneumatic launcher. It will y autonomously to 15,000 ft. and cruise climb throughout the flight to 25,000 ft., before descending to its destination. There, it will be caught by a net restraint system, where the hard drive will be extracted. The Carrier Pigeon is truly a unique vehicle for its size, range, and robustness.
84

Neural Processing of Magnetic Intensity Cues by Lesioned Homing Pigeons (Columba livia) in a Magnetic Conditioning Paradigm

Acerbi, Merissa Lynne 18 April 2017 (has links)
No description available.
85

Entre biodiversité et pratiques cynégétiques patrimoniales : étude comparée des chasses traditionnelles aux gibiers migrateurs terrestres dans le Sud-Ouest de la France et au Québec : le cas du pigeon ramier (France) et de l'oie blanche (Québec)

Difilippo, Gabriel 31 May 2022 (has links)
Ce mémoire est le fruit d'une recherche de Master, effectué dans le cadre de la formation « TEMA+ : European Territories: Heritage and Development program» et de la maitrise en Ethnologie et Patrimoine de l'Université de Laval à Québec. L'art cynégétique est un art de prédilection pour ce qui s'agit de modifier et d'influer directement sur la nature. L'Homme se doit d'ajuster et de maitriser le terrain afin de mettre en place des pièges efficaces, rendant ainsi possible la capture de proies jusque-là inatteignables. Les techniques de chasse, se transmettent et se perfectionnent ainsi de génération en génération à travers le temps et l'espace. C'est dans ce cadre que se situe l'essence de ce projet, il s'agit, en effet, d'effectuer une étude comparée entre des techniques traditionnelles de chasses au gibier migrateur terrestre dans le Sud-Ouest de la France et au Québec. L'objectif premier du projet est la confrontation transdisciplinaire de la notion de "nature" à celle de "culture". Plus précisément il s'agit de démontrer les interactions de l'Homme sur son milieu et des milieux sur l'Homme pour des pratiques sociales et culturelles données. En effet, l'observation de différentes pratiques cynégétiques fait émerger la relation particulière entre technique et sociabilité ainsi que le lien logique entre pratique traditionnelle et espaces naturels. Pour cela, le choix des cas d'études s'est porté sur la palombe pour l'exemple français et sur l'oie blanche pour l'exemple canadien, deux entités qui se révèlent d'abord fortement similaires puis porteuses d'identités fortes qui dévoilent tout un pan patrimonial et culturel sur les territoires concernés. Ce mémoire se propose d'apporter quelques éléments de réponses à la problématique suivante : « Comment des pratiques culturelles liées à la chasse de migrateurs terrestres, marqueurs d'identités et de patrimoines en France et au Québec, autorisent la création de zones biologiquement transformées avec potentiellement la mise en place d'écosystèmes complexes ? ». Par l'application d'une méthodologie exploratoire, d'observations participantes et in situ, et par la comparaison de données récoltées à l'occasion d'entretiens semi-dirigés, tenter de répondre à cette question a permis la mise en évidence d'archétypes foncièrement marqués malgré une distance géographique évidente. Fort des rémanences révélées entre les deux cas d'étude, une limite s'est établie au carrefour de l'histoire législative respective des deux univers cynégétiques mis en parallèle.
86

GIANT voice : An alternative destiny for city glitches

Tang, Yuqing January 2024 (has links)
My degree project aims to find an alternative destiny to the city glitches- the forgotten industrial buildings which are constantly being torn down. All the memories, the urban creatures that nest inside them, are considered disposable in city planning. The aim of this project is not to stop urban development but to create spaces where this endless force magically stops, a bubble of “utopia”, where the urban beings take their own time to flourish, undisturbed. I focus my project on the abandoned factory house Nitrolackfabriken in the southern part of Stockholm, a building threatened with demolition. I went through three stages in the design process: first background research, second a design proposal about turning the building into a functional culture house, and lastly landed on a design intervention where I gave up the previous culture house proposal, refused it on behave of the building itself, and gave the house back to what is already inside. I created three design interventions in this new part of the project: the garden, the pond, and the fire room. I see the building and all the small beings nesting inside as part of an intertwining relationship, a living being, a “GIANT.” I abstracted her into a human-like shape, wishing to create an emotional resonance between the GIANT and us. To remind us that we are all part of this complexity.
87

Johann Friedrich von Uffenbach. Sammler – Stifter – Wissenschaftler / Johann Friedrich von Uffenbach. Collector - Donor - Scientist

Meyerhöfer, Dietrich 28 January 2020 (has links)
No description available.

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