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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

Essays on the user cost of capital and financing of the agricultural firm /

Lagerkvist, Carl Johan, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
42

Η επίδραση των εισροών στην ποιότητα του εδάφους στο οροπέδιο της κοινότητας Ομαλών στη νήσο Κεφαλληνία

Βαγγελάτου, Πόλυ 13 July 2010 (has links)
Σκοπός της παρούσας εργασίας είναι η μελέτη της επίδρασης των εισροών στην ποιότητα του εδάφους των καλλιεργειών, στο οροπέδιο της κοινότητας Ομαλών στη νήσο Κεφαλληνία, μέσω της αξιοποίησης των στοιχείων που προκύπτουν από την δομή και την περιγραφή του συγκεκριμένου αγροτικού οικοσυστήματος. Η μελέτη έγινε σε βιολογικούς και συμβατικούς ελαιώνες και αμπελώνες και διήρκησε 1 χρόνο. Κατά την διάρκεια του χρόνου αυτού, πραγματοποιήθηκαν δειγματοληψίες από τα υπό μελέτη εδάφη και προσδιορίσθηκαν χημικές και βιολογικές ιδιότητες. Συγκεκριμένα προσδιορίστηκαν το pH, η Ικανότητα Ανταλλαγής Κατιόντων, η οργανική ουσία, η Ηλεκτρική αγωγιμότητα, ο φώσφορος, τα ανταλλάξιμα κατιόντα K, Na και Mg, το ολικό άζωτο, το βόριο τα νιτρικά και η εδαφική αναπνοή. Για την αξιοποίηση των αποτελεσμάτων των εδαφολογικών αναλύσεων ήταν απαραίτητη η γνώση των καλλιεργητικών πρακτικών που εφαρμόζονται στα αγροτεμάχια καθώς και οι ποσότητες των εισροών σε αυτά. Για το σκοπό αυτό πραγματοποιήθηκαν συνεντεύξεις σε αγρότες της περιοχής με την χρήση ερωτηματολογίων ανοιχτού τύπου. Από τα ερωτηματολόγια προέκυψε ότι η υψηλότερη ενεργειακή εισροή στο εδαφικό υποσύστημα είναι η κοπριά τόσο στην περίπτωση της βιολογικής καλλιέργειας όσο και συμβατικής καλλιέργειας ελιάς και αμπέλου. Η εντατική χρήση υψηλών ποσοτήτων κοπριάς συμβάλλει στην βελτίωση των χημικών και βιολογικών ιδιοτήτων του εδάφους αλλά εγκυμονεί κινδύνους για την ποιότητα του. / In the following research the effects of agroecosystem inputs on soil quality of crops at plateau Omala of Cephalonia island via the exploitation of elements that result through the study of the structure and the description of particular agroecosystem, were studied. The research had a duration of above 1 year, in which samplings from the soil and their chemical and biological attributes were not only realized but also evaluated concretely pH,Cation Exchange Capacity, organic matter, Electrical Conductivity, the phosphor, Exchangeable Cations K, Na and Mg, total N, NO3, the boron and the microbial rate, were measured. For the exploitation of results of soil analysis it was essential to have obtain knowledge of farming practices that is applied in the farmyards as well as the quantities of inputs. This aim was realised through interviews with farmers of the region with the use of open type questionnaires. The result of these questionnaires was that the higher energy input in the soil subsystem is manure. The intensive use of high quantities of manure contributes to the improvement of the chemical and biological attributes of soil but gestates dangers for soil quality.
43

Dissolved organic carbon (DOC) : Differences in reactivity amongst water sources to boreal streams in Sweden

Eriksson, Lukas January 2018 (has links)
The importance of dissolved organic carbon (DOC) to aquatic environments is well established in the scientific community. In boreal landscapes, small streams receive water from headwater lakes, mires, and discrete flow paths that drain riparian soils. The goal of this study was to investigate the importance of these discrete riparian inputs (DRIPs) as sources of DOC and to explore whether quantity and quality of DOC from DRIPs differs from other sources in the landscape, including groundwaters that are not as hydrologically connected to streams. To do this, I collected water from already established riparian groundwater wells installed at the Krycklan Catchment Study (KCS) in northern Sweden, as well as from an adjacent lake, stream, and mire. Microbial activity (respiration) was analyzed in 24-hour laboratory incubations using a metabolically active dye, resazurin (Raz) which in the presence of aerobic respiration transforms into resorufin (Rru). Rru is easily measured in the lab, and its production can serve as a proxy for rates of microbial respiration. DOC concentration was also measured at each location, along with specific absorbance at 254 nm (SUVA254) and the absorbance ratio (254/365 nm) as indices of DOC quality. The results show a large variation in DOC concentration among potential water sources to the stream. Furthermore, there was a strong correlation (R2=0.96) between Rru production and DOC concentration among these sources, but no significant difference (p=0.067) in median Rru production between DRIPs and non-DRIPs. Overall, these results highlight important spatial variability in DOC from different water sources in the landscape, which likely have important consequences for patterns of microbial respiration in streams.
44

Biofertilizantes: identificação das barreiras regulatórias e propostas para viabilizar esse insumo agrícola

Moraes, João Guilherme Vanzella 09 February 2015 (has links)
Submitted by João Guilherme Vanzella Moraes (jg_moraes@hotmail.com) on 2015-03-06T13:52:00Z No. of bitstreams: 1 DISSERTAÇÃO Joao Moraes MPAgro 28012015_revisado 03032015.pdf: 578821 bytes, checksum: b5c3c44b85620945e1ddf8255644cc3c (MD5) / Approved for entry into archive by Fabiana da Silva Segura (fabiana.segura@fgv.br) on 2015-03-06T13:53:40Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO Joao Moraes MPAgro 28012015_revisado 03032015.pdf: 578821 bytes, checksum: b5c3c44b85620945e1ddf8255644cc3c (MD5) / Made available in DSpace on 2015-03-06T13:56:12Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO Joao Moraes MPAgro 28012015_revisado 03032015.pdf: 578821 bytes, checksum: b5c3c44b85620945e1ddf8255644cc3c (MD5) Previous issue date: 2015-02-09 / The focus of this research study is to identify bottlenecks in the Brazilian legislation that regulate biofertilizers by means of a revision of the main rules, acts and normative instructions of the sector, and to propose measures that facilitate its development. Inputs are part of the Brazilian legislation since the publication of the first Fertilizer Law in 1980; its uses are also described in academic publications. However the lack of registration of biofertilizer products at the Ministry of Agriculture, Livestock and Food Supply (MAPA) until the end of 2014 requires immediate attention from the input sector, its leaders and legislative figures. Understanding the implication and effects of the current legislation towards the adoption of the input, as well as the implications of the revision of norms and regulations present in this work, will support the input sector, political leaders and research bodies to adequate norms and technical procedures that enable the registration of solutions for the biofertilizer sector and that facilitate the access to biofertilizers by farmers. This study has revised the Brazilian legislation relevant to the biofertilizer input, interviewed political leaders, institutional leaders and prominent figures of private companies about the main challenges for the development of the sector. It also investigated the situation of the biofertilizer sector in other countries such as Canada, the Unites States and countries of the European Union through the revision of laws and relevant documents, and by means of interviews conducted with professionals of the input sector and representative institutions present in the markets mentioned above. Although there are differences in the definitions proposed by the various countries and other corresponding categories, the difficulties faced by companies of the nutrition sector to register biofertilizers is consistent to the efforts of US companies to create the biostimulant class, and to those of the majority of the European countries analyzed. It was identified that the current legislation and its interpretation and the requirements to launch new products do not fully comply with the needs of the biofertilizer producing sector. The biofertilizer sector does not have the same regulatory expertise found in the crop protection sector in order to better define validation protocols with the responsible authority. Changes in legislation, better articulation among the production chain and greater interaction with the Ministry of Agriculture, Livestock and Food Supply (MAPA) are essential to secure the viability of the biofertilizer input. Keywords: biofertilizers, legislation, inputs. / O tema central dessa pesquisa é identificar gargalos da legislação brasileira por meio de revisão das principais leis, decretos e instruções normativas que norteiam o ambiente regulatório para os biofertilizantes, e propor medidas que facilitem o desenvolvimento do setor. O insumo faz parte da legislação brasileira desde a publicação da primeira lei de fertilizantes em 1980, e tem seu uso descrito em trabalhos acadêmicos. No entanto, a falta de registros de produtos biofertilizantes junto ao Ministério da Agricultura, Pecuária e Abastecimento (MAPA) até o final do ano de 2014 merece atenção do setor de insumos e das lideranças que legislam. O entendimento das implicações e efeitos da legislação na adoção do insumo, bem como as implicações para a revisão das normas, presentes no trabalho, apoiam o setor de insumos, as lideranças políticas e a pesquisa na adequação das normas e procedimentos técnicos que viabilizem o registro das soluções do setor de biofertilizantes e o acesso facilitado por parte dos agricultores. O trabalho revisou a legislação brasileira relevante para o insumo biofertilizante, e entrevistou lideranças políticas, institucionais e de empresas no que diz respeito às principais dificuldades enfrentadas para o melhor desenvolvimento do setor. Investigou-se também a situação apresentada em outros países, como Estados Unidos, Canadá e países da União Européia através da revisão de leis e documentos, e de entrevistas com profissionais do setor de insumos e representantes de instituições atuantes nos mercados mencionados. Apesar de diferenças nas definições propostas pelos vários países e outras classificações congruentes, as dificuldades que empresas do setor de nutrição enfrentam no registro de biofertilizantes correspondem aos desafios também enfrentados por empresas para criar a classe de bioestimulantes nos Estados Unidos, e principalmente àqueles da maioria dos países europeus analisados. Identificou-se que a legislação vigente e sua interpretação, e exigências para o lançamento de novos produtos não atendem plenamente o setor produtor de biofertilizantes, o qual ademais não possui a mesma expertise regulatória que o setor agroquímico para melhor definir seus protocolos de validação junto ao órgão anuente. Mudanças na legislação, melhor articulação da cadeia produtiva no entendimento das necessidades, e maior interação das entidades representativas com o Ministério da Agricultura, Pecuária e Abastecimento (MAPA) se fazem essenciais para viabilidade do insumo biofertilizante.
45

Alterações no solo, nutrição e crescimento de Eucalyptus sp. decorrentes do uso de diferentes qualidades de água / Changes in soil, nutrition and growth of Eucalyptus sp. due to the use of different water qualities

Rocha, Silvania Arreco 11 March 2011 (has links)
Made available in DSpace on 2016-12-23T13:51:55Z (GMT). No. of bitstreams: 1 Silvania Arreco Rocha.pdf: 712358 bytes, checksum: f494398f0a7b23cb4cefa387bc56f32f (MD5) Previous issue date: 2011-03-11 / O descarte de efluentes pode representar um problema ambiental quando seu destino final são os corpos hídricos. Entretanto, devido à presença de nutrientes em sua composição, o uso agroflorestal pode representar um aumento de produtividade e economia de fertilizantes. O objetivo desta pesquisa foi avaliar o crescimento inicial e a nutrição de três espécies de Eucalyptus sp., quando submetidas à irrigação com diferentes qualidades de água, bem como analisar as mudanças na fertilidade do solo. O delineamento experimental utilizado para montagem do experimento foi inteiramente casualizado no esquema fatorial 2×3×3 (dois períodos de avaliação, três níveis de qualidade de água e três espécies de eucalipto), com três repetições. Mudas de E. grandis, E. urophylla e urograndis com 90 dias foram plantadas em vasos de 5 L preenchidos com Latossolo Vermelho Amarelo. Vinte dias após o plantio das mudas nos vasos, iniciou-se a irrigação das mudas com as diferentes qualidades de água. Foram realizadas duas análises de crescimento para determinar a altura da parte aérea; o diâmetro do colo; a área foliar; a massa seca da parte aérea; a massa seca da raiz; a massa seca total; a relação entre a parte aérea e a raiz; a taxa de crescimento absoluto; a taxa de crescimento relativo; a razão de área foliar; a taxa de assimilação líquida; a relação entre a altura da parte aérea e o diâmetro do colo; e a porcentagem de raízes. No final do experimento, as folhas das plantas coletadas nas duas avaliações foram encaminhadas ao laboratório para determinação dos teores de nitrogênio, fósforo, potássio, cálcio, magnésio, enxofre, zinco, ferro, manganês, cobre e boro. Também foram determinadas as medidas de pH, fósforo, potássio, cálcio, magnésio, alumínio, acidez potencial, soma de bases, capacidade de troca catiônica efetiva, capacidade de troca catiônica a pH 7, saturação de bases, alumínio e saturação de alumínio. Os resultados indicaram que o efluente de esgoto proporcionou maior crescimento das mudas do que as águas de abastecimento e de piscicultura. Em relação às espécies, o urograndis apresentou maior diâmetro do colo, massa seca total, taxa de crescimento absoluto e taxa de assimilação líquida; e assim como o E. urophylla, maior taxa de crescimento relativo. Por outro lado, o E. grandis e o E. urophylla apresentaram maior razão de área foliar e maior relação entre altura da parte aérea e diâmetro do colo. Foram verificados maiores teores foliares de nitrogênio e ferro nas mudas fertirrigadas com efluente de esgoto doméstico, enquanto os teores de cálcio, manganês, cobre e boro foram maiores nas mudas irrigadas com água de abastecimento e nas mudas fertirrigadas com água de piscicultura. No solo, apenas o teor de potássio foi afetado pela qualidade de água utilizada, sendo maior com a utilização do efluente de esgoto e água de piscicultura / The discard of effluent can represent an environmental problem when its final destination is the hydric resources. However, due to the presence of nutrients in its composition, the agroforestry use may represent an increase in productivity and fertilizer economy. Accordingly, this research aims to study the initial growth and nutrition of three species of Eucalyptus sp. when subjected to irrigation with different water qualities, and analyzes changes in soil fertility. The experimental design used in the experiment was randomized in a factorial 2 × 3 × 3 (two periods of three levels of water quality and three species of eucalyptus), with three replications. Seedlings of Eucalyptus grandis, E. urophylla and urograndis with 90 days were planted in 5 L pots filled with Oxisol. Twenty days after planting, the seedlings started to be irrigated with different water qualities. Two growth analysis were performed to determinate the shoot height, stem diameter, leaf area, shoot dry weight, root dry mass, total dry weight, index between shoot and root, absolute growth rate, relative growth rate, leaf area ratio, liquid assimilation rate, index between shoot height and diameter and percentage of roots. In the end of the experiment, the plant leaves collected on the two tests were sent to the laboratory to determine the levels of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, zinc, iron, manganese, copper and boron. In addition, soil samples were sent to the laboratory to determine the levels of pH, phosphorus, potassium, calcium, magnesium, potential acidity, total bases, effective cation exchange capacity, cation exchange capacity at pH 7, base saturation, and saturation in aluminum. The results indicated that the sewage effluent gave a higher growth than the water supply and fish farming water. For the species, urograndis showed greater root mass, total dry matter, absolute growth rate, liquid assimilation rate, and as well as E. urophylla, higher relative growth rate. Furthermore, E. grandis and E. urophylla had higher leaf area ratio. With regard to leaf analysis, higher levels of leaf nitrogen and iron in seedling fertigated with sewage effluent were found, while the levels of calcium, manganese, copper and boron were higher in the seedlings irrigated with tap water and fertigated with fish farming water. In soil, only the potassium was affected by the quality of water used, being higher with the use of sewage effluent and fish farming water
46

Elementos-traço As, Ba, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Se e Zn em latossolos e plantas de milho após treze aplicações anuais de lodo de esgoto /

Andrade, Mauricio Gomes de. January 2011 (has links)
Orientador: Wanderley José de Melo / Banca: Ademir Sérgio Ferreira de Araújo / Banca: Beatriz Monte Serrat / Banca: Marcos Omir Marques / Banca: Otávio Antônio de Camargo / Resumo: O uso do lodo de esgoto (LE) com finalidade agronômica e/ou condicionador é uma das alternativas ambientalmente e economicamente atraente, quando comparadas a outros destinos (incineração, aterro sanitário, etc.). As substâncias inorgânicas potencialmente tóxicas contidas no LE são uma das maiores preocupações ao meio ambiente e à cadeia trófica. O objetivo deste trabalho foi avaliar os teores e o efeito cumulativo dos elementos As, Ba, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Se e Zn, em dois latossolos vermelhos (um eutroférrico - LVef, e um distrófico - LVd) e plantas de milho (Zea mays L.) cultivadas nos mesmos após a aplicação de LE por treze anos ininterruptos. Em condições de campo e delineamento experimental de blocos ao acaso, cada solo recebeu quatro tratamentos (0; 5; 10 e 20 t de LE ha1) com cinco repetições. Amostras dos insumos agrícolas aplicados na cultura do milho, LE, solos, materiais vegetais e materiais de referência certificados foram digeridas em forno de micro-ondas (método 3051A), e os analitos foram quantificados por ICP-OES. Após 13 aplicações anuais sucessivas de LE no LVef e LVd, os maiores teores dos ETs foram encontrados no LVef e ainda não atingiram o valor de investigação (VI) agrícola (mais restritivo) da resolução 420 do CONAMA. Persistindo a atual taxa de aplicação de LE e teores médios de ET incorporados aos solos, é de se esperar que o Ba, Cd, Cr, Cu, Ni e Zn serão os primeiros elementos a atingir o VI no LVef. Para o LVd, o primeiro elemento a atingir o VI é o Cr somente. Os teores de ET encontrados nos insumos agrícolas não devem causar impacto ambiental imediato. Os ETs não proporcionaram fitotoxidade ou contaminação nas partes aéreas, folhas para diagnose e grãos das plantas de milho / Abstract: The use of sewage sludge (SS) as agronomic and/or soil conditioner purposes presents a correct environmental and economically attractive alternative when compared to other disposal methods as incineration and landfills. The potentially toxic inorganic substances contained in SS is a major concern for the environment and food chain. This work aimed evaluate the content and the cumulative effect of the Trace Elements (TE) As, Ba, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Se, and Zn in two different soils: an Eutroferric Clayed Red Latosol (Typic Eutrorthox - "E") and a Dystrophic Red Latosol (Typic Haplorthox - "H") and with maize plants (Zea mays L.) growth after fertilize the soil with SS for thirteen years continuously. Under field conditions and under a randomized blocks experimental design each soil received four treatments (0, 5, 10, and 20 t of SS ha-1) with five replications. Fertilizers, SS, soils, vegetal materials, and the reference material were digested in microwave oven (method 3051A) and the analytes were quantified by ICP-OES. After thirteen years fertilizing the soil with SS in the soils "E" and "H", the higher amounts were found in the "E" and these amounts did not reach the agricultural investigation value (more restrictive) yet. Persisting the actual fertilization rate of SS and an average amount of TE incorporated in the soil, Ba, Cd, Cr, Cu, Ni, and Zn will be probably the firsts elements to reach the agricultural investigation value in the "E". To "H", the first element to reach this value will be probably Cr. The TE found in the fertilizers should not cause immediate environmental impact. The TE did not provide neither phytotoxicity nor contamination in the maize aerial part, diagnose leaf, and grains / Doutor
47

Uso da geoestatística e da lógica fuzzy no estudo da variabilidade espacial e temporal da produtividade e da fertilidade do solo em café conilon

Costa, Felipe Pianna 11 July 2011 (has links)
Made available in DSpace on 2016-12-23T14:37:37Z (GMT). No. of bitstreams: 1 Felipe Pianna Costa.pdf: 3475348 bytes, checksum: 7fefca7d2f234254e722f1148c4e3e44 (MD5) Previous issue date: 2011-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nos últimos anos, vem aumentando a adoção das técnicas de agricultura de precisão (AP) em culturas anuais e perenes no Brasil. Porém, para a cafeicultura de montanha estão sendo realizadas pesquisas para adaptação de soluções tecnológicas viáveis na aplicação das técnicas de AP. O objetivo desta pesquisa foi utilizar os conceitos e métodos da análise espacial e temporal no estudo da produtividade e fertilidade do solo e desenvolver uma metodologia de classificação fuzzy para a definição de zonas de aplicação de insumos em três safras de café conilon. O trabalho foi realizado em uma área experimental cultivada com a variedade de Coffea canephora Pierre ex Froenher (ROBUSTA TROPICAL Emcaper 8151‟). Os pontos de amostragens de produtividade (sc ha-1) e atributos químicos do solo (pH, P, K, CTC e V) foram georreferenciados, compondo uma malha irregular totalizando 109 pontos. Cada ponto amostral foi composto de cinco plantas para a colheita do café, com as amostras de solo coletadas na profundidade de 0,0 0,2 m na projeção da copa do cafeeiro. Foi utilizada a análise geoestatística para interpolação dos dados, recursos de geoprocessamento para determinação do índice de produtividade e fertilidade do solo entre as safras e lógica fuzzy para análise multicritério na definição de zonas de aplicação de insumos. Nas três safras, a produtividade e os atributos químicos do solo apresentam variabilidade espacial e temporal. A análise quantitativa por meio dos mapas possibilitou observar que os níveis de produtividade e fertilidade do solo apresentam regiões com alternância de valores entre as diferentes safras. Os índices quantitativos obtidos de produtividade de -18% e -57,1% e fertilidade de 24,3% e 12,3% entre a segunda e a primeira safra e a terceira e a segunda safra, respectivamente, representam a variabilidade temporal e a distribuição espacial da produtividade e da fertilidade do solo entre as diferentes safras. A classificação fuzzy auxilia na tomada de decisão para definição de zonas de aplicação de insumos na área, revelando em maior percentual da área, notas de média aplicação de insumos de 3,4 a 6,3 nas três safras. / In recent years, the adoption of precision agriculture techniques in annual and perennial crops was increasing in Brazil. However for the coffee cultivated in mountainous regions are still being conducted research to adapt technology solutions feasible to apply these techniques. The objective of this research was to use the concepts and methods of spatial and temporal analysis in the study of soil fertility and productivity and develop a fuzzy classification methodology for defining areas of application of inputs in three conilon coffee crops. The work was developed an area of Coffea canephora Pierre ex Froenher (ROBUSTA TROPICAL Emcaper 8151‟). In the selected area an irregular grid was built, including 109 points of samplings demarcated and georeferenced. Each sample point was composed of five plants to evaluate the productivity (sc ha-1) and chemical soil attributes (pH, P, K, CTC e V) in the layer of 0-20 cm of depth in canopy‟s projection. The geostatistic analysis was applied to data interpolation, geoprocessing resources to determinate the productivity and soil fertility level and a multicriteria analysis was carried out applying fuzzy logic to definition of inputs application zones. At the three crops, the productivity and soil atributes show spatial and temporal variability. The quantitative analysis showed alternating regions of rate productivity and soil fertility values between the different crops. The quantitative levels of productivity -18% and -57.1% and fertility 24.3% and 12.3% between the second and first crop and the third and second crop, respectively, represent temporal variability and spatial distribution of the productivity and fertility between the different crops. The classification fuzzy subsidizing the decision-making process to define inputs application zones, showing in the mainly percentage of the area, medium marks of inputs application 3.4 to 6.3 on the three crops.
48

Fatores relacionados à decisão de compra por produtores da Coopertinga

Calazans, Anna Flávia Santos 01 December 2016 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-16T20:34:17Z No. of bitstreams: 1 DISSERTAÇÃO Anna Flávia Santos Calazans.pdf: 1186242 bytes, checksum: ef0fa6b9211514d09a86cae5533e66d6 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-17T21:33:22Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO Anna Flávia Santos Calazans.pdf: 1186242 bytes, checksum: ef0fa6b9211514d09a86cae5533e66d6 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-17T21:35:14Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO Anna Flávia Santos Calazans.pdf: 1186242 bytes, checksum: ef0fa6b9211514d09a86cae5533e66d6 (MD5) / Made available in DSpace on 2018-07-17T21:35:21Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO Anna Flávia Santos Calazans.pdf: 1186242 bytes, checksum: ef0fa6b9211514d09a86cae5533e66d6 (MD5) Previous issue date: 2016-12-01 / Este trabalho objetivou estudar o cenário de produtores da cooperativa COOPERTINGA, localizada em Formoso, Minas Gerais, e discorrer sobre o perfil e os pontos mais importantes voltados para as atividades no campo. A pesquisa foi realizadacom 19 produtores associados da Coopertinga, localizada na Zona Rural do Município do Formoso - MG, na região Noroeste do Estado de Minas Gerais, a uma altítude média de 1.026 metros, cujas distâncias são: 36 Km de Formoso – MG, 120 Km de Buritis – MG, 300 km de Unaí – MG, 265 Km de Brasília – DF e 175 Km de Formosa – GO. Esta pesquisa foi composta por 56 questões, com o intuito de averiguar o insumo agrícola mais importante, detalhes da aquisição de insumos, marcas e marketing, custos, potencial produtivo e qualidade dos mesmos. Os dados foramexpressos em porcentagem simples, além da descrição qualitativa dos dados. Desta maneira, foi possível conhecer o cenário de produtores da cooperativa e suas necessidades. O marketing dos produtos provenientes de empresas do agronegócio deve agir em prol de satisfazer a necessidade dos produtores, tornando seus produtos vantajosos, principalmente no requisito custo x benefício. Os produtores avaliaram o vigor como requisito primordial na escolha de sementes, que é um dos insumos mais importantes para se obter a produtividade, e, consequentemente, a lucratividade. Assim, uma cooperativa, a partir de facilidades na aquisição de insumos, de assistência e de informação, dentre outros, possibilita que seus associados possam competir no mercado, assegurando meios de sobrevivência aos produtores. / This work aimed to study the scenario of producers of the cooperative COOPERTINGA, located in Formoso, Minas Gerais, and discuss the profile and the most important points for the activities in the field. The research was carried out with 19 Coopertinga Associated Producers, located in the Rural Area of the Municipality of Formoso - MG, in the Northwest region of the State of Minas Gerais, at an average altitude of 1,026 meters, whose distances are: 36 Km from Formoso - MG, 120 Km from Buritis - MG, 300 km from Unaí - MG, 265 Km from Brasília - DF and 175 Km from Formosa - GO. This research was composed of 56 questions, with the purpose of ascertaining the most important agricultural input, details of the acquisition of inputs, about brands and marketing, costs, productive potential and quality. Data wereexpressedas a simple percentage, besides the qualitative description of the data. In this way, it was possible to know the scenario of cooperative producers and their needs. The marketing of products from agribusiness companies should act to meet the need of producers, making their products advantageous, especially in the cost-benefit requirement. Producers have evaluated vigor as a primary requirement in seed selection, which is one of the most important inputs for achieving productivity, and hence the profitability. Thus, a cooperative, based on facilities in the acquisition of inputs, assistance and information, among others, enables its members to compete adequately in the market, ensuring means of survival for producers.
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Organisation of primary auditory cortex in the mouse : a topography of inputs and responses

Webb, Jonathan J. B. January 2013 (has links)
No description available.
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Design Exploration and Application of Reversible Circuits in Emerging Technologies

Kotiyal, Saurabh 07 April 2016 (has links)
The reversible logic has promising applications in emerging computing paradigms, such as quantum computing, quantum dot cellular automata, optical computing, etc. In reversible logic gates, there is a unique one-to-one mapping between the inputs and outputs. To generate a useful gate function, the reversible gates require some constant ancillary inputs called ancilla inputs. Also to maintain the reversibility of the circuits some additional unused outputs are required that are referred to as the garbage outputs. The number of ancilla inputs, the number of garbage outputs and quantum cost plays an important role in the evaluation of reversible circuits. Thus minimizing these parameters are important for designing an efficient reversible circuit. Reversible circuits are of highest interest in optical computing, quantum dot cellular automata and quantum computing. The quantum gates perform an elementary unitary operation on one, two or more two-state quantum systems called qubits. Any unitary operation is reversible in nature, and hence, quantum networks are also reversible, to conclude the quantum computers must be built from reversible logic components. The main contribution of this dissertation is the design exploration and application of reversible circuits in emerging nanotechnologies. The emerging technologies explored in this work are 1) Optical quantum computing 2) Quantum computing. The first contribution of this dissertation is Mach-Zehnder interferometer based design of all optical reversible binary adder. The all optical reversible adder design is based on two new optical reversible gates referred as optical reversible gate I (ORG-I) and optical reversible gate II (ORG-II) and the existing all optical Feynman gate. The two new reversible gates ORG-I and ORGI-II have been proposed and can implement a reversible adder with a reduced optical cost which is equal to the number of MZI switches required, less propagation delay, and with zero overhead in terms of number of ancilla inputs and the garbage outputs. The proposed all optical reversible adder design based on the ORG-I and ORG-II reversible gates are compared and shown to be better than the other existing designs of reversible adder proposed in the non-optical domain in terms of number of MZI switches, delay, the number of ancilla inputs and the garbage outputs. The proposed all optical reversible adder will be a key component of an all optical reversible arithmetic logical unit (ALU), that is a quite essential component in a wide variety of optical signal processing applications. In the existing literature, the NAND logic based implementation is the only known implementation available for reversible gates and its functions. There is a lack of research in the direction of NOR logic based implementation of reversible gates and functions. The second contribution of this dissertation is the design of NOR logic based n-input and n-output reversible gates, one of which can be efficiently mapped into optical computing using the Mach-Zehnder interferometer (MZI), while the other can be mapped efficiently in optical computing using the linear optical quantum gates. The proposed reversible NOR gates work as a corresponding NOR counterpart of NAND logic based Toffoli gates. The proposed optical reversible NOR logic gates can implement the reversible boolean logic functions with less number of linear optical quantum logic gates with reduced optical cost and propagation delay compared to the implementation using existing optical reversible NAND gates. It is illustrated that an optical reversible gate library having both optical Toffoli gate and the proposed optical reversible NOR gate is superior compared to the library containing only the optical Toffoli gate: (i) in terms of number of linear optical quantum gates when implemented using linear optical quantum computing (LOQC), (ii) in terms of optical cost and delay when implemented using the Mach-Zehnder interferometer. The third contribution of this dissertation is a binary tree-based design methodology for a NxN reversible multiplier. The proposed binary tree-based design methodology for a NxN reversible multiplier performs the addition of partial products in parallel using the reversible ripple adders with zero ancilla bit and zero garbage bit; thereby, minimizing the number of ancilla and garbage bits used in the design. The proposed design methodology shows improvements in terms of number of ancilla inputs and garbage outputs compared to all the existing reversible multiplier designs. The methodology is also extended to the design of NxN reversible signed multiplier based on modified Baugh-Wooley multiplication methodology.

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