A secagem para conservação de produtos agrícolas e alimentícios e feita geralmente com emprego de eletricidade ou combustível fóssil, que incrementa o custo do produto final. Dessa forma, faz-se necessário o desenvolvimento de sistemas que utilizam energia renovável, como a solar, de modo a reduzir custos sem prejuízo na qualidade do produto. Assim, um secador solar de convecção natural misto foi projetado e construído, bem como um sistema de aquisição de dados (SAD) utilizando telemetria, para monitorar temperatura e umidade relativa, ambas do ar, no interior do secador. Para o projeto do secador pesquisou-se na literatura diversos modelos já estudados, a m de reunir idéias para definição de um modelo particular. Apos construiu, um teste operacional foi realizado no secador, utilizando tomate cereja. O SAD foi construído em três partes: o transmissor com os sensores, protegido em caixa selada e afixado ao secador solar; o receptor, acoplado a um PC em local abrigado e cerda de 60 m distante do secador; e o software de aquisição de dados no PC. Os sensores foram fixados em três pontos diferentes do secador e protegidos com pedaços de tubo de PVC. O transmissor permite visualização instantânea de dados num LCD, gravação em cartão de memória SD e transmissão via RF para o receptor/PC. O software no PC e um aplicativo web, permitindo acesso externo e apresentando os dados em forma de gracos, tabela ou ilustração, alem de possuir um sistema de alerta via SMS para temperatura. Em testes de campo, o SAD apresentou bom funcionamento. Houve pouca perda de dados na transmissão, devido a veículos no caminho do sinal RF, e os sensores responderam corretamente as variações do ambiente. O secador apresentou boa resistência as intempéries, e o teste com tomate cereja mostrou que esta operacional. / Drying for preservation of agricultural and food products is usually done with the use of electricity or fossil fuel, increasing the cost of the nal product. Therefore, it is necessary to develop systems that use renewable energy such as solar, to reduce costs without impairing the quality of the product. Thus, a mixed-mode natural-circulation solarenergy dryer and a telemetry data acquisition system (DAS) to log air temperature and air relative humidity inside the dryer were designed and built. For the dryer design, in the literature several models already studied were investigated in order to gather ideas for dening a particular model. Once built, an operational test was conducted in the dryer, using cherry tomatoes. The DAS was built in three parts: the transmitter with the sensors, protected in a weather-resistant enclosure and xed in the solar dryer; the receiver, coupled to a PC in a sheltered place; and the PC software data acquisition. The sensors were put at three dierent points in the dryer and xed with PVC pipe pieces. The transmitter allows data instant viewing on an LCD, SD card logging and RF transmission to the receiver/PC. The PC software is a web application, allowing external access and presenting the data in graph, table or illustration, in addition to having an alert system to temperature by SMS. In eld tests, the DAS was worked well. There was little data loss in transmission due to vehicles in the RF signal path, and sensors correctly responded to the changing environment. The dryer had good weather resistance, and the test with cherry tomatoes showed that it is operational.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2006. / Härtill 4 uppsatser.

O presente trabalho tem por objetivo principal apresentar a avaliação térmica, energética e financeira para um sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios, o qual utiliza como fonte de energia a energia solar e uma fonte de energia auxiliar. Dois tipos de fonte de energia auxiliar são utilizados, uma fonte utiliza biomassa como combustível e a outra utiliza energia elétrica. O sistema é composto por um coletor solar térmico, tipo placa plana de exposição indireta, uma fonte de energia auxiliar. O software TRNSYS é utilizado como ferramenta para executar as simulações, tendo como meta alcançar a temperatura do ar de 70°C na entrada da câmara de secagem. Os resultados são apresentados em função das temperaturas da placa absorvedora, do ar de saída do coletor solar e do ar de entrada na câmara de secagem e em função da quantidade de energia, por hora, fornecida para o ar de secagem pelo coletor solar (ganho de energia útil) e pela fonte de energia auxiliar. Calcula-se o custo horário da energia considerando a utilização da biomassa e da energia elétrica, resultando no custo da biomassa equivalente a 42,5% do custo da energia elétrica.Embora os custos com insumos sejam mais baratos para a utilização do sistema com biomassa, a implementação desse sistema é mais cara, sendo viável apenas em longo prazo. O retorno do investimento para o sistema com biomassa ocorre no quarto ano, enquanto que o sistema com energia elétrica obtém retorno no primeiro ano. / This work aim to perform thermal, energy and financial analysis for an air heating system of a hybrid solar dryer for agricultural products, which uses as energy source a combination of solar energy and an auxiliary power source. Two types of external auxiliary power source for energy are used, biomass and electric power. The dryer is composed by an indirect flat plate flat plate collector, an external energy source and a drying chamber. The software TRNSYS is used to run the hybrid solar dryer simulations. The simulations goal is for the system to achieve 70°C air temperature at the drying chamber inlet. The results are showed as a function of the absorber flat plate temperature, the solar thermal collector outlet air temperature and the drying chamber inlet air temperature as a function of the energy amount per hour supplied to the drying air by the solar collector (useful energy gain) and by the external auxiliary power source. The energy cost per hour is calculated by assuming each one of the sources, biomass and electric power. It resulted that biomass costs 42.5% of the electrical power total costs. Although the source material costs are cheaper for biomass usage, it implies higher implementation costs, thus requiring long range usage analysis to prove practicable. The biomass system return of investment occurs at the fourth year while at the electrical power system return of investment occurs at the first year.

The objective of this diploma thesis is to recommend an optimal way of creating a reliable quality assessment system for products of crop and livestock origin. The selected companies have been searched for key aspects of these systems and evaluated. Further, the certification of quality systems in the Czech Republic was also examined.

As relações entre a União Europeia (UE) e os seus parceiros comerciais incluem Acordos Preferenciais de Comércio (APCs) com países em desenvolvimento para produtos agrícolas e industriais, destacando-se países da África, Caraíbas e Pacífico. A política de caráter cooperativo no setor agrícola da APC-UE, possui por objetivo a preservação do ambiente, segurança alimentar, crescimento econômico e desenvolvimento sustentável. Excetuando-se esses Acordos Preferenciais, a União Europeia possui no setor agrícola um dos segmentos de maior proteção comercial. Trata-se do principal mercado para os produtos agrícolas brasileiros. No entanto, esse setor, no Brasil, poderia obter melhor desempenho caso a UE não praticasse tarifas de importação elevadas aos seus produtos. Assim sendo, aplica-se no presente trabalho o modelo gravitacional para mensurar o efeito de criação ou desvio de comércio, resultado da aplicação de tarifas pela União Europeia com relação aos seus 48 parceiros comerciais selecionados, incluindo-se o Brasil, e também o impacto de um possível Acordo Preferencial de Comércio entre Brasil e União Europeia. A análise enfoca os efeitos para um grupo selecionado de produtos agrícolas, que recebem a incidência de picos tarifários, incluindo-se carne bovina congelada, carne bovina fresca, carne de frango, carne suína, açúcar bruto e suco de fruta. O período considerado para a análise compreende os anos de 1996 a 2013, ou seja, desde o alargamento da União Europeia no ano de 1995. O modelo gravitacional é estimado por meio do modelo de efeitos fixos e os resultados mostram a existência de desvio de comércio com relação às importações europeias de carne bovina fresca (SH 0202) e carne suína (SH 0203) e impacto positivo da concretização de um Acordo Preferencial de Comércio para carne bovina fresca (SH 0201), carne bovina congelada (SH 0202) e carne de frango (SH 0207). Tais resultados confirmam as hipóteses levantadas na literatura com relação à consolidação do referido acordo. Ou seja, os resultados indicam que o Brasil pode aumentar suas exportações de produtos agrícolas para a União Europeia caso ocorra um acordo preferencial que elimine as barreiras tarifárias impostas pelo bloco da UE. / Trade relations between the European Union (EU) and its trading partners have feature for the granting of tariff reduction or exemption for developing countries, through preferential agreements. With regard to preferential trade agreements (PTA) put in place by the European Union, stands out those performed with the group of African, Caribbean and Pacific (ACP) countries for agricultural and industrial products. The cooperative nature of politics in the ACP-EU agricultural sector has the objective of preserving the environment, food security, economic growth and sustainable development. Except for some preferred sealed agreements with some countries, the European Union has in the agricultural sector, one of the segments most subject to trade protection. With regard to Brazil, the European Union is the main market for its agricultural products. Even so, the Brazilian agricultural sector could have a better performance if the EU did not ascribe excessively high import tariffs to their products. Therefore, a gravity model is used in this analysis to measure the effect of trade creation or trade diversion as a result of the tariff applied by the European Union in relation for 48 selected trading partners, including Brazil and also the impact of a possible Preferential Trade Agreement between Brazil and the European Union. The analysis focuses on the effects for a selected group of agricultural products receiving the incidence of tariff peaks, including frozen beef, fresh beef, chicken, pork, raw sugar and fruit juice The period considered for the analysis covers the years from 1996 to 2013, which incorporates the enlargement of the European Union starting at 1995. The gravity model is estimated using the fixed effects model and the results show the existence of trade diversion with respect to European imports of fresh beef (HS 0202) and pork (HS 0203) and positive impact of the implementation of a Preferential Trade Agreement for fresh beef (HS 0201), frozen beef (HS 0202) and chicken (HS 0207). These results confirm the hypotheses rose in the literature with regard to the consolidation of the Agreement. That is, the results indicate that Brazil could increase its exports of agricultural products to the EU in the event of a preferential agreement eliminating tariff barriers imposed by the EU bloc.

O presente trabalho tem por objetivo principal apresentar a avaliação térmica, energética e financeira para um sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios, o qual utiliza como fonte de energia a energia solar e uma fonte de energia auxiliar. Dois tipos de fonte de energia auxiliar são utilizados, uma fonte utiliza biomassa como combustível e a outra utiliza energia elétrica. O sistema é composto por um coletor solar térmico, tipo placa plana de exposição indireta, uma fonte de energia auxiliar. O software TRNSYS é utilizado como ferramenta para executar as simulações, tendo como meta alcançar a temperatura do ar de 70°C na entrada da câmara de secagem. Os resultados são apresentados em função das temperaturas da placa absorvedora, do ar de saída do coletor solar e do ar de entrada na câmara de secagem e em função da quantidade de energia, por hora, fornecida para o ar de secagem pelo coletor solar (ganho de energia útil) e pela fonte de energia auxiliar. Calcula-se o custo horário da energia considerando a utilização da biomassa e da energia elétrica, resultando no custo da biomassa equivalente a 42,5% do custo da energia elétrica.Embora os custos com insumos sejam mais baratos para a utilização do sistema com biomassa, a implementação desse sistema é mais cara, sendo viável apenas em longo prazo. O retorno do investimento para o sistema com biomassa ocorre no quarto ano, enquanto que o sistema com energia elétrica obtém retorno no primeiro ano. / This work aim to perform thermal, energy and financial analysis for an air heating system of a hybrid solar dryer for agricultural products, which uses as energy source a combination of solar energy and an auxiliary power source. Two types of external auxiliary power source for energy are used, biomass and electric power. The dryer is composed by an indirect flat plate flat plate collector, an external energy source and a drying chamber. The software TRNSYS is used to run the hybrid solar dryer simulations. The simulations goal is for the system to achieve 70°C air temperature at the drying chamber inlet. The results are showed as a function of the absorber flat plate temperature, the solar thermal collector outlet air temperature and the drying chamber inlet air temperature as a function of the energy amount per hour supplied to the drying air by the solar collector (useful energy gain) and by the external auxiliary power source. The energy cost per hour is calculated by assuming each one of the sources, biomass and electric power. It resulted that biomass costs 42.5% of the electrical power total costs. Although the source material costs are cheaper for biomass usage, it implies higher implementation costs, thus requiring long range usage analysis to prove practicable. The biomass system return of investment occurs at the fourth year while at the electrical power system return of investment occurs at the first year.

The purpose of this thesis is to assess the implications of Information Communication Technologies (ICTs) on the agricultural supply chain in Greece by examining the relationships between farmers and their intermediaries, and their interactions during the buying and selling process. More specifically, the focus of the research takes place in Pouri, a small village in central Greece whose economy centers around Apple Farming, where we can observe the exchange of locally grown goods between farmers and intermediaries. The thesis consists of two parts; the first part examines how Greek farmers perceive the process of buying and selling agricultural products and how they respond to problems within their current structure; through observing processes, conducting interviews and collecting narrative stories to identify the issues, we assess whether it would be advantageous for farmers to implement ICTs as part of the solution. The second part consists of a review of the academic literature to examine the same or similar situations in the agricultural supply chain of other global regions and their economic contexts. Lastly, a thorough thematic analysis of the research data provides a better understanding of the issues facing farmers and their needs as they pertain to ICTs, to improve the agricultural supply chain and the entire rural sector.

Kooperasies, as werktuie ter doelwitbereiking vir graanprodusente, het sedert hul totstandkoming onderskeibare ontwikkelingsfases deurgegaan. Die toepassing van kooperasie as mededingingstrategie deur graanprodusente is grootliks bei"nvloed deur die veranderings wat tydens die ontwikkelingsfases voorgekom het. Aksies wat in die loop van hierdie ontwikkellngsfases ingestel was, het mettertyd onduidelikhede oor die bestaansgrondslag van die kooperasies laat ontstaan. Die klJmaat van politieke veranderings wat tans in die land heers, kan ook belangrike veranderings meebring ten opsigte van die grondslag waarop kooperasies funksioneer. Pie uitwerking van die verwagte veranderings kan kooperasies forseer om strategiese aanpassings in hul strukture te maak ten einde steeds suksesvol te kan bly voortbestaan. · Graanprodusente verkeer in 'n posisie wat vereis dat daar besin moet word oor strategiee wat gevolg kan word ten einde steeds suksesvol in die onsekere markomstandighede mee te ding. Die toepassing van kooperasie as mededingingstrategie waarvolgens graanprodusente deur lidmaatskap van die kooperasies in die mark deelgeneem het, kom nou ook onder die loep. Die hoofprobleem waarop daar dus in hierdie studie gefokus word, is om te bepaal of kooperasie as mededingingstrategie geskik is om die individuele en kollektiewe belange van graanprodusente te bevorder. Van die belangrikste bevindings van die studie is: Graanprodusente voorsien dat kooperasie individuele graanprodusente se markoptrede kan versterk. Graanprodusente is van mening dat hulle deur middel van kooperasie wat manifesteer in selfstandige besigheidsondernemings, genaamd ''kooperasies", 'n positiewe invloed vir graanprodusente op die mark kan uitoefen. Daar kcan nie 'n beduidende negatiewe, of positiewe persepsie oor onderlinge mededinging en die invloed wat die vryemarkbedeling daarop uitoefen, by graanprodusente gei"dentifiseer word nie. Dit blyk egter dat sommige graanprodusente die vryemarkbedeling as 'n belangrike markfaktor bejeen. Ander graanprodusente huldig 'n meer buigsame benadering jeens die vryemarkbedeling. Graanprodusente is, met enkele klemverskille, van mening dat die kooperasies nie daarin slaag om die tradisionele kooperasiebeginsels in die wyse waarop kooperasies hul besigheid bedryf, volledig toe te pas nie. Graanprodusente het oor die algemeen gesien duidelike menings oor die noodsaaklikheid daa.rvan dat die staat nie by die graanbedryf meet inmeng nie. Ander tipes ondersteuningstrategiee, soos die oprigting van beslote korporasies of maatskappye, geniet wisselende steun. 'n Beduidende groep graanprodusente is onseker oor moontlikhede om maatskappye met kapitaalgroei as basis te skep, om sodoende in geheel met kooperasies weg te doen. / Co-operatives have experienced distinguishable changes. The application of co-operation as a competitive strategy by g~in producers was largely influenced by the changes. The prevailing political changes can also instigate important changes with regard to co-operatives. Grain producers must revise strategies to maintain successful competition in the market. The study investigates co-operation as a competitive strategy to advance the individual and collective interests of grain producers, Findings are: Grain producers are convinced that co-operation enhances the market related actions of individual grain producers. Grain producers can, through co-operation, exercise a positive influence in the market. No definite negative or positive perception concerning the influence of the free market system upon mutual competition could be identified. Grain producers are convinced that the state should not interfere with the grain industry. / Business Management / M. Admin. (Business Management)

Kooperasies, as werktuie ter doelwitbereiking vir graanprodusente, het sedert hul totstandkoming onderskeibare ontwikkelingsfases deurgegaan. Die toepassing van kooperasie as mededingingstrategie deur graanprodusente is grootliks bei"nvloed deur die veranderings wat tydens die ontwikkelingsfases voorgekom het. Aksies wat in die loop van hierdie ontwikkellngsfases ingestel was, het mettertyd onduidelikhede oor die bestaansgrondslag van die kooperasies laat ontstaan. Die klJmaat van politieke veranderings wat tans in die land heers, kan ook belangrike veranderings meebring ten opsigte van die grondslag waarop kooperasies funksioneer. Pie uitwerking van die verwagte veranderings kan kooperasies forseer om strategiese aanpassings in hul strukture te maak ten einde steeds suksesvol te kan bly voortbestaan. · Graanprodusente verkeer in 'n posisie wat vereis dat daar besin moet word oor strategiee wat gevolg kan word ten einde steeds suksesvol in die onsekere markomstandighede mee te ding. Die toepassing van kooperasie as mededingingstrategie waarvolgens graanprodusente deur lidmaatskap van die kooperasies in die mark deelgeneem het, kom nou ook onder die loep. Die hoofprobleem waarop daar dus in hierdie studie gefokus word, is om te bepaal of kooperasie as mededingingstrategie geskik is om die individuele en kollektiewe belange van graanprodusente te bevorder. Van die belangrikste bevindings van die studie is: Graanprodusente voorsien dat kooperasie individuele graanprodusente se markoptrede kan versterk. Graanprodusente is van mening dat hulle deur middel van kooperasie wat manifesteer in selfstandige besigheidsondernemings, genaamd ''kooperasies", 'n positiewe invloed vir graanprodusente op die mark kan uitoefen. Daar kcan nie 'n beduidende negatiewe, of positiewe persepsie oor onderlinge mededinging en die invloed wat die vryemarkbedeling daarop uitoefen, by graanprodusente gei"dentifiseer word nie. Dit blyk egter dat sommige graanprodusente die vryemarkbedeling as 'n belangrike markfaktor bejeen. Ander graanprodusente huldig 'n meer buigsame benadering jeens die vryemarkbedeling. Graanprodusente is, met enkele klemverskille, van mening dat die kooperasies nie daarin slaag om die tradisionele kooperasiebeginsels in die wyse waarop kooperasies hul besigheid bedryf, volledig toe te pas nie. Graanprodusente het oor die algemeen gesien duidelike menings oor die noodsaaklikheid daa.rvan dat die staat nie by die graanbedryf meet inmeng nie. Ander tipes ondersteuningstrategiee, soos die oprigting van beslote korporasies of maatskappye, geniet wisselende steun. 'n Beduidende groep graanprodusente is onseker oor moontlikhede om maatskappye met kapitaalgroei as basis te skep, om sodoende in geheel met kooperasies weg te doen. / Co-operatives have experienced distinguishable changes. The application of co-operation as a competitive strategy by g~in producers was largely influenced by the changes. The prevailing political changes can also instigate important changes with regard to co-operatives. Grain producers must revise strategies to maintain successful competition in the market. The study investigates co-operation as a competitive strategy to advance the individual and collective interests of grain producers, Findings are: Grain producers are convinced that co-operation enhances the market related actions of individual grain producers. Grain producers can, through co-operation, exercise a positive influence in the market. No definite negative or positive perception concerning the influence of the free market system upon mutual competition could be identified. Grain producers are convinced that the state should not interfere with the grain industry. / Business Management / M. Admin. (Business Management)

Drying contributes a significantly important role in processing of agricultural products in Vietnam, particularly for high-value agricultural exports. Conventionally thermal-based drying techniques have remained critical disadvantages in term of enhancing product quality and process efficiency. The typical disadvantages include deterioration of organoleptic and nutritional properties, highenergy consumption, expensive costs yet low efficiency and hazards to environment change due to the consumption of fossil fuel sources. Electrohydrodynamics (EHD) drying technology has been demonstrated as an innovative solution for drying enhancement in various applications. This paper aims at an overview of the state-of-the-art EHD drying technology to enhance heat and mass transfer in agricultural drying processes. A case study is then presented to demonstrate an even better process efficiency, compared to the state-of-the-art EHD drying technology, and to shorten the gap “research-to-market”. Finally, this study shows obviously potential applications of this innovative technology in sustainable development of food and post-harvesting agricultural processing for Vietnam in the future. / Sấy khô đóng một vai trò quan trọng trong việc chế biến và bảo quản nông sản sau thu hoạch tại Việt Nam, đặc biệt đối với các mặt hàng nông sản cao cấp phục vụ xuất khẩu. Các phương pháp sấy khô bằng nhiệt truyền thống tồn tại nhiều nhược điểm trong việc nâng cao hiệu quả sấy và bảo đảm chất lượng nông sản. Những nhược điểm nổi bật bao gồm: biến đổi thành phần hóa học và giảm giá trị dinh dưỡng của nông sản sau sấy do sử dụng nhiệt trong quá trình sấy, tiêu hao nhiên liệu lớn, chi phí nhiên liệu, lắp đặt và duy trì hệ thống sấy cao nhưng hiệu suất thấp và đặc biệt ảnh hưởng tới môi trường do sử dụng các nguồn nhiên liệu hóa thạch. Công nghệ sấy cải tiến khíđiện động lực học (EHD) hiện tại đã cho thấy tiềm năng thay thế các phương pháp sấy truyền thống. Bài báo tập trung giới thiệu cơ chế sấy các sản phẩm nông sản bằng công nghệ EHD; qua đó tác giả giới thiệu một mô hình sấy đã chế tạo thành công cho hiệu quả thậm chí còn cao hơn các mô hình hiện tại, đồng thời dễ dàng triển khai trong ngành công nghiệp sấy khô nông sản. Nghiên cứu này chỉ ra tiềm năng ứng dụng to lớn của công nghệ EHD trong phát triển bền vững các quá trình sấy khô nông sản cao cấp tại Việt Nam trong tương lai.