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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.
111

E-xcursionismes 2.0. L'excursionisme català a l'inici del segle XXI. Una visió des de l'antropologia

Roma i Casanovas, Francesc 27 January 2010 (has links)
Aquesta tesi estudia la situació social de l'excursionisme a la Catalunya dels primers anys del segle XXI des de la perspectiva de l'antropologia de l'esport. Temàticament es divideix en dues parts clarament diferenciades. La primera d'elles fa una anàlisi descriptiva de la situació actual d'aquest fet social des d'aproximacions quantitatives i qualitatives. En la segona part s'estudien les noves comunitats virtuals que estan sorgint i que serveix per vehicular la sociabilitat pròpia d'aquest moviment. L'estudi analitza les principals línies de futur del fet excursionista a Catalunya. / Esta tesis estudia la situación social del excursionismo en la Cataluña de los primeros años del siglo XXI desde la perspectiva de la antropología del deporte. Temáticamente se divide en dos partes claramente diferenciadas. La primera de ellas hace un análisis descriptivo de la situación actual de este hecho social desde aproximaciones cuantitativas y cualitativas. En la segunda parte se estudian las nuevas comunidades virtuales que están surgiendo y que sirven para vehicular la sociabilidad propia de este movimiento.El estudio analiza las principales líneas de futuro del hecho excursionista en Cataluña. / This thesis examines the social situation of mountainneering in Catalonia in the early years of the 21th century from the perspective of anthropology of sport. Thematically is divided into two clearly differentiated parts. The first part is a descriptive analysis of the current situation of this social fact from quantitative and qualitative approaches. The second part focuses on the new virtual communities that are emerging and which serves to convey sociability characteristic of this movement.The study shows the main lines of future hikers made in Catalonia.
112

Innovative Milk Foamer : Product Development

Axelsson, Stefan January 2010 (has links)
This report presents the primary development process of an innovative milk foamer. The project is structured as the primary development process that is used at Electrolux Floor Care and Small Appliances AB, Global Primary Development and Innovation department in Stockholm, Sweden. The aim was to develop a milk foamer with innovative solutions to provide Electrolux with a unique product. The objective was to create a product that highly meets customer requirements and in the same time is feasible to develop into a selling product. All the aspects regarding a consumer product had to be considered. To create innovative solutions thorough investigations of the physics behind foaming and foam are studied and documented. The difference in foam quality when using different ways of foaming is documented and possible explanations is discussed. The primary development process range from pre-study and customer research to designing prototypes and verifications. Most of the report deals with standalone solutions but there is also a part of the report that deals with integrated solutions and cooperating solutions that would be used together with espresso machines. The result is a variety of concepts and four fully working standalone prototypes. Two prototypes are further developed and are highly interesting to Electrolux.
113

Essays on fuel efficiency and vehicle demand dynamics

Liu, Yizao 02 June 2011 (has links)
Reducing automobile-based gasoline consumption has been a major U.S. public policy issue recently. A key driving force behind policymakers' desire is the concern of environmental externalities and national security. Currently, there are three public policies towards reducing automobile gasoline consumption: raising federal gasoline tax, raising the Corporate Average Fuel Economy (CAFE) Standards and vehicle scrappage subsidies of government to retirement of old vehicles. My research studies the effectiveness of these policies in the United States. Among all polices, economists often argue that higher gasoline tax would be more effective in improving fuel economy efficiency. In my first chapter, I ask how gasoline prices influence households' automobile replacement decisions and thus market fuel economy efficiency, which is measured by average mileage per gallon in a city. I specify and estimate a structural dynamic model of consumer preference for new and used vehicles following the methodology proposed by Gowrisankaran and Rysman (2009). Since gasoline costs accounts for 65% of total operating costs, the current and future gasoline price must need to be taken into consideration for rational forward-looking consumers when they are making vehicle choices. Besides, the replacement decision for vehicles is dynamic as well: facing depreciation as the automobile ages and the improving features for new products, consumers need to decide whether to replace the vehicle in the current period or later. Therefore, a dynamic model of consumer choice would be crucial to correct policy evaluation of fuel economy efficiency, while previous literature fails to consider the dynamics. By taking dynamics into consideration, I am able to capture the inherent dynamic nature of a forward-looking consumer's decision, with rational expectation on the evolution of vehicle attributes and retail gasoline prices. I estimate the model using a rich dataset combing vehicle registration data on different cities, vehicle characteristic data, average gasoline price, etc. Although a high gasoline tax is never put in practice in the U.S. and may not be political feasible, I further conduct an experiment of raising gasoline tax to test how fuel economy efficiency is affected based on my model estimates. Experiments suggest that keeping a $4 gasoline price would result in a steady trend for a city's fleet fuel efficiency increase, while doubling current rate will only increase fuel efficiency in the first several years, but experience drops over time. The Corporate Average Fuel Economy (CAFE) are regulations in the United States that intended to improve the average fuel economy of cars and light trucks sold in the US. However, it is long been realized that with a more fuel efficiency car, consumers may be induced to drive more which partially offsets the original energy saving by the policy. Therefore, to assess the effectiveness of CAFE standards, it is crucial to ask: how fuel economy efficiency, which is measured by mileage per gallon (MPG), affects households' vehicle mileage traveled and its distribution. In my second chapter, I answer the question by estimating a structural model for joint determination of vehicle fuel efficiency choice and vehicle mileage traveled each year with a detailed micro-level data of National Household Travel Survey 2001. I further study the distributional effects on vehicle miles of fuel efficiency using instrumental quantile regression. Comparison on results and tests of weak instruments between my method and literature suggest that my model and choice of instruments provide consistent estimates, while using choice probabilities as instruments is not valid. My results support some earlier findings of rebound effects with a more precise quantitative estimation. In addition, I find new evidence that costs associated with raising CAFE standards vary across different quantiles of annual mileage driven and are especially high for those with below-average vehicle mileage driven. These findings also provide rationale in support of a tax on mileage, which is more effective in reducing gasoline consumptions, comparing to the costs of CAFE standards. My third chapter focus on 2009 CARS Program (Cash-for-Clunker). The 2009 CARS program attempted to boost the sale of new fuel efficient vehicles to replace old gas guzzlers. The program established a two-tier incentive system depending on whether buyers purchased a passenger vehicle or an SUV. The result is that many of the new purchased vehicles are indeed SUVs. The CARS program collected information about the old scrapped vehicles and linked it to the actual purchase of the new vehicles. It is thus possible to analyze the effect of preference inertia in choices by comparing the characteristics of old and new vehicles. The fact that effective prices that consumers face are determined by the mileage class of the old car also allows us to evaluate the distribution of valuation trade-offs between mileage and other characteristics such as size, performance, and vehicle class. My findings suggest that the 2009 Cash-for-Clunker is not very effective in terms of affecting consumers' choice of SUVs and big cars. For transactions under the program, consumers still prefer SUVs and large cars. The extra $1000 rebates actually increase consumers' tastes towards SUVs. / text
114

The decline of the Chinese matriarch : the struggle to reconcile "old" with "new"

Lee, Tara 05 1900 (has links)
The thesis examines representations of the matriarch in three Chinese Canadian texts: SKY Lee's Disappearing Moon Cafe, Wayson Choy's The Jade Peony, and Denise Chong's The Concubine's Children. The matriarch is the female head of the Chinese household who is able to gain substantial power by manipulating the assets granted to her in a patriarchal system. Dislocated from her home in China, she serves in these texts as the focal point for the collision between the New World, Canada, and the Old World, China. Confronted by a new environment, the matriarch must decide whether she will choose conformity or identity experimentation. The thesis is concerned with the way Chinese Canadian writers negotiate multiple identities through narrators who must come to terms with the divided loyalties of the women of the past. The analysis of the matriarch's identity shifts is informed by the work of the feminist theorists, Elspeth Probyn and Moira Gatens, who explore the productive potentials of rebelling against binary codes. The thesis is divided into three chapters that discuss how the texts come close to embracing identity fluidity, but cannot overcome the need to reach a coherent representation of the matriarch. The first chapter is devoted to Disappearing Moon Cafe, and argues that Lee's narrator sacrifices her female characters, albeit reluctantly, in order to privilege feminism over her Chinese heritage. The second chapter turns to The Jade Peony and discusses how Choy's child narrators give in to binary thinking by relegating Poh-Poh, the Old One, to the realm of memories to make room for the New Ways. The final chapter on The Concubine's Children explores Chong's desire to redeem a grandmother who wreaked havoc on the family when she defied traditional gender roles. The thesis concludes by determining that Lee, Choy, and Chong are reaching for a multi-voiced reading of the past, but cannot yet articulate a way out. The uncertainty of their representations of the matriarch signals their efforts to move beyond binaries to a state of coexisting identity categories.
115

Sata Ineko and Hirabayashi Taiko: The Café and Jokyû as a Stage for Social Criticism / Café and Jokyû as a Stage for Social Criticism

Kusakabe, Madoka 09 1900 (has links)
xii, 251 p. / Sedimentations of transformations and experiences empowered the 20th century writers Sata Ineko and Hirabayashi Taiko as writers. Because of their mutual belief in the early principles of the proletarian literary movement--writing the reality of the working class from their perspectives--both produced works centered on daily life. In not only delineating but also examining the daily occurrences, their stories and critiques acutely exposed the issues, the conditions, and the exploitation of the working class under capitalism, particularly the unfair and unreasonable treatment of women and women workers under the patriarchal slogan "Good Wives and Wise Mothers" and the discrimination of women workers and writers even within the proletarian movement. The café proved the best site for both to offer keen analyses. Materializing the actual working experiences of jokyû (café waitresses), they exposed the superficiality of Japanese modernity in the 1920s and 30s, the suppression and oppression of women under patriarchy, commodification and exploitation of working women under capitalism, and the ultimate consequences--social myopia and deterioration of human life. While the café was for jokyû a site of exploration and challenge by overturning the dominant power hierarchy practiced in society, for Sata and Hirabayashi, writing about the café challenged the prejudice and confinement of existing categorizations such as "women," "women workers," " jokyû ," "women writers," and "proletarian writers." Both Sata and Hirabayashi treated the café and jokyû as realistic and multifaceted. To strengthen this realism, both writers relied on their own corporeal experiences and sensations, supporting honest illustrations of power dynamics and the dual-system oppression of women at play within and beyond the café environment. Both acknowledged the body as a site of complication and possibility. Through their acknowledgments beyond the surface inscriptions that restrict and limit who and what lies within, both Sata and Hirabayashi contended that the body was an interactive and potentially productive catalyst for change. For them, the corporeal experience proved more effective for gaining consciousness, obtaining class-consciousness, and eventually achieving ideological resolution than through doctrinal readings and teachings. / Committee in charge: Stephen Kohl, Chairperson; Alisa Freedman, Member; Tze-Lan Sang, Member; Jeffrey Hanes, Outside Member
116

Mucilagem residual em cafe cereja descascado e seus efeitos na qualidade da bebida e na produção de cafes especiais / Residual mucilage in peeled coffee cherry and its effects on the quality of the drink and on the production on special coffee

Henao Cuellar, Jose Duban 26 September 2007 (has links)
Orientadores: Marlene Rita de Queiroz, Niurka Maritza Almeyda Hj-Isa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-09T21:28:05Z (GMT). No. of bitstreams: 1 HenaoCuellar_JoseDuban_D.pdf: 3961756 bytes, checksum: 4ae64eef41798beb73b9c2f5d34cba2b (MD5) Previous issue date: 2007 / Resumo: A crescente demanda por cafés de maior qualidade e menos contaminante como o café cereja descascado, aliada às escassas informações sobre este produto tipicamente brasileiro e a necessidade de melhorar sua secagem mecânica motivaram este trabalho que teve o objetivo de avaliar os efeitos de diferentes conteúdos de mucilagem residual no café cereja descascado sobre diferentes atributos da bebida e na operação de secagem. Grãos de café arábica (Coffea arábica L.) foram tratados para a obtenção de bebidas preparadas com amostras contendo diferentes teores de mucilagem residual. Uma equipe de provadores foi selecionada e treinada para avaliar sensorialmente as bebidas resultantes. Estudos da cinética de secagem sob diferentes temperaturas de secagem e tempos de repouso foram realizados para os cafés de baixo teor de mucilagem. Construíram-se as isotermas de dessorção para as temperaturas de 50 e 73°C e teores de mucilagem residual de 16,1 e 52,7%. Foi desenvolvido um modelo preditivo para a determinação do tempo de secagem requerido para atingir a umidade final de 12%, analisado através da metodologia de superfície de resposta. Os modelos de Fick e Page apresentaram bom ajuste aos dados experimentais de cinética de secagem, sendo a melhor representação obtida para o modelo de Page. Na secagem em camada delgada, para temperaturas do ar de exaustão entre 46,6 e 66,0°C com velocidade média de 0,21 m/s, as difusividades efetivas variaram entre 7,47x10-11 e 3,08x10-10 m2/s. Os modelos Peleg e Halsey modificado foram os que melhor representaram as isotermas de sorção de café cereja descascado. Para a estimativa das umidades de equilíbrio dinâmicas, a equação proposta por Fioreze mostrou-se altamente satisfatória. No estudo dos requerimentos de ar para a secagem em camada delgada de café cereja descascado, verificou-se que a velocidade deveria ser superior a 0,42 m/s. O melhor conceito sensorial correspondeu à faixa de menores conteúdos de mucilagem residual / Abstract: This work was based, partly, in the increasing demand for coffees of higher quality, like the peeled coffee cherry that has consolidated as a typical Brazilian product, in addition to being less contaminating than washed coffee. Because it is a relatively new product, information is scarce. As far as the problems associated to the quality of coffee, the phases of harvest and drying have been identified as the most important ones; and to increase competitiveness, the necessity to improve the mechanical drying is considered as a high-priority. Based on these considerations, the present work has as main objective the evaluation of the effects of different contents of residual mucilage of peeled coffee cherry on the diferents attribute of the drink and the operation of drying. The desorption isotherms for 50ºC and 73ºC and residual mucilage content of 16.1% and 52.7% were determined, finding that the models of Peleg and Halsey modified represented better the isotherms. In order to estimate the dynamic equilibrium moisture, the proposed equation by Fioreze turned out to be highly satisfactory. In thin layer drying, for temperatures of exhausted air between 46.6ºC and 66.0ºC and average air speed of 0,21 m/s, effective diffusivities varied from 7.47x10-11 to 3.08x10-10 m2/s. In the study of air requirements for the thin layer drying of peeled coffee cherry, it was verified that the average speed must be higher than 0,42 m/s. A panel for sensory evaluation of the resulting drinks, from coffees with different residual mucilage content, was selected and trained. The best sensorial concept corresponded to the lower residual mucilage content range, and for this range, through studies of kinetic of drying associated to different drying temperatures and tempering time, a predictive model for the determination of the required drying time was obtained in order to reach a final moisture of 12%, this analyzed through the response surface method. The drying experimental data showed good adjustment with the models of Fick and Page, being better for the last one / Doutorado / Tecnologia Pós-Colheita / Doutor em Engenharia Agrícola
117

Purificação da enzima polifenoloxidase do cafeeiro, sua relação com resistencia a pragas e o controle da sintese de seu principal substrato, o acido clorogenico / Coffee polyphenoloxidase purification, its relation with plague resistance and synthesis control of its maim substrate, chlorogenic acid

Melo, Geraldo Aclecio 30 June 2005 (has links)
Orientador: Paulo Mazzafera / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T10:18:49Z (GMT). No. of bitstreams: 1 Melo_GeraldoAclecio_D.pdf: 1320706 bytes, checksum: 5f501b7dd60a44ae72341950498d75f7 (MD5) Previous issue date: 2005 / Resumo: Polifenoloxidase - PFO (EC 1.14.18.1 ou EC 1.10.3.2) é uma enzima de ampla distribuição entre as plantas e catalisa a hidroxilação de monofenóis a o-difenóis e a oxidação destes para o-diquinonas. Sua função em plantas tem sido relacionada a mecanismos de defesa contra patógenos e pragas. Em cafeeiro, o ácido 5-cafeoilquínico, também conhecido como ácido clorogênico (CGA) é o principal substrato da PFO e ambos, enzima e substrato, estão presentes em quantidades expressivas nos frutos e nas folhas desta planta. O CGA também está relacionado com mecanismos de defesas das plantas e como tal é considerando importante substrato em reações de oxidação, principalmente aquelas mediadas pela PFO. No presente estudo, com objetivo de conhecer características da PFO de folhas do cafeeiro, de averiguar sua ação em mecanismos de defesa nessa planta e de entender fatores ligados à síntese e ao acúmulo de seu principal substrato foram feitas a purificação e caracterização dessa enzima, estudos da expressão de sua atividade, bem como estudos de expressão de enzimas da via de síntese do CGA em cafeeiro. Com o uso de técnicas de precipitação com sulfato de amônio, cromatografias de troca iônica, interação hidrofóbica e exclusão molecular foi possível obter a PFO com alto grau de pureza. A enzima apresentou massa molecular de 40,5 Kda e preferência pelo ácido 5-cafeoilquínico como substrato. Seqüências de peptídeos obtidas após digestão da proteína e análise por espectrometria de massas mostraram-se homólogas a seqüências de PFO de várias outras plantas. O nível constitutivo de atividade da PFO observado para quinze genótipos de café variou de 3,8 a 88,0 unidades de atividade/mg de proteína, entretanto não teve relação direta com resistência a pragas e doenças nessa planta. A resistência ao bicho mineiro foi significativamente relacionada ao nível de compostos fenólicos, entretanto, ácido 5-cafeoilquínico, o principal substrato da PFO em café, não teve relação com essa resistência, sugerindo a importância de outros compostos fenólicos como substratos da PFO. Dano mecânico, tratamento com ácido metiljasmônico, inoculação com esporos do fungo Hemileia vastatrix e a infestação com ovos do inseto Perileucoptera coffeella levaram a respostas variadas nos níveis de atividade de PFO nos genótipos avaliados. Baseando-se nesses resultados, conclui-se que a ação da PFO na resistência do cafeeiro a pragas e doenças pode estar relacionada ao potencial oxidativo do tecido e não simplesmente uma maior atividade; que o tipo e quantidade de substrato encontrado no tecido podem ser importantes na resistência do cafeeiro e que entre os genótipos pode existir a especialização de mecanismos de resistência envolvendo a ação da PFO. Estudos de expressão por RT-PCR de fenilalanina amônia-liase (PAL), cinamato 4-hiroxilase (C4H), coumarato 3-hidroxilase (C3H), hidroxicinamoil-CoA ligase (4CL) e hidroxicinamoil-CoA:D-quinato hidroxicinamoil transferase (CQT), enzimas da via de síntese do CGA, tiveram sua expressão reduzida à medida que o tecido envelhece. No endosperma foi observado um decréscimo acentuado de expressão no final da maturação dos frutos. Plântulas estioladas obtidas pela germinação de sementes no escuro e transferidas para luz mostraram aumentos significativos no conteúdo de CGA após 24 horas. Esses aumentos foram transientes e coincidiram com a expressão da PAL, C4H, C3H, 4CL e CQT. Os resultados indicam existência de controle da síntese de CGA e a existência de mecanismos de controle da expressão em comum para as cinco enzimas estudadas / Abstract: Polyphenoloxidase - PPO (EC 1.14.18.1 ou EC 1.10.3.2) is an enzyme with broad distribution among plants and catalyzes the hydroxylation of monophenols to o-diphenols and the oxidation of these to o-diquinones. Its function on plants has been related to defense mechanisms against pathogens and plagues. 5-Caffeoylquinic acid, also known as chlorogenic acid (CGA), is the main PPO substrate in coffee tissues and both, enzyme and substrate are present on substantial quantities in fruits and leaves. CGA is also referred to having connection with plants defense mechanisms and it is also an important substrate on oxidation reactions, mainly those mediated by PPO. Therefore, in order to increase our knowledge on the coffee PPO characteristics, to verify its role in defense mechanisms and also to understand the factors connected to the synthesis of CGA, coffee leaf PPO was purified and characterized regarding kinetic parameters and its activity in leaves of several coffee species exposed or not to pest (leaf miner) and disease (leaf rust). Also studies on the expression of the enzymes of CGA synthesis were carried out. By using ammonium sulfate precipitation followed by chromatographic steps on ionic exchange, hydrophobic interaction and molecular exclusion resins it was possible to purify PPO to homogeneity. The enzyme presented a molecular mass of 40,5 Kda and used 5-cafeoylquinic acid as the preferred substrate. Peptide sequences obtained after digestion of the purified PPO and analysis through mass spectrometry were homologous to PPO sequences of several other plants. The constitutive level of PPO activity observed for 15 coffee genotypes varied from 3,8 to 88,0 units of activity/mg of protein, but did not have a direct relationship with resistance to plagues in this plant. Resistance to leaf miner was significantly related to the level of phenolic compounds. However, 5-caffeoylquínic acid, the main substrate of PPO on coffee, was not related with resistance, suggesting the importance of other phenolic compounds as PPO substrates. Mechanical damage, treatment with methyljasmonic acid, inoculation with spores from Hemileia vastatrix and the infestation with the insect Perileucoptera coffeella led to varied results of the PPO activity in the evaluated genotypes. Based on these results, we conclude that the PPO role in the coffee resistance to plagues and diseases might be related to the oxidative potential of the tissue and not only on the PPO activity; that the kind and quantity of PPO substrate found in the tissue might be important for the resistance of the coffee tree and that there may be specific mechanisms of resistance involving PPO action among the genotypes. RT-PCR studies of the expression of phenylalanine ammonia-lyase (PAL), cinnamate 4-hyroxylase (C4H), coumarate 3-hydroxylase (C3H), hydroxycinnamoyl-CoA ligase (4CL) and hydroxycinnamoyl-CoA:D-quinate hydroxycinnamoyl transferase (CQT), which code for enzymes of the CGA biosynthetic pathway, showed that the expression of these enzymes decrease with tissue aging. In the endosperm, an evident decrease on the expression was observed in the end of the fruit ripening. Etiolated seedlings obtained by germination of coffee seeds in the dark and transferred into light showed significant increasing on the CGA content after 24 hours. The increase was transient and followed the expression pattern of PAL, C4H, C3H, 4CL and CQT. The results indicate that CGA biosynthesis is coordinately regulated by the expression of the five enzymes / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal
118

Uso de imagens de alta e media resolução espacial no estudo de areas cafeeiras / Use of high and medium spatial resolution images in the study of coffee areas

Ramirez, Glaucia Miranda 13 August 2018 (has links)
Orientador: Jurandir Zullo Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-13T05:57:27Z (GMT). No. of bitstreams: 1 Ramirez_GlauciaMiranda_D.pdf: 28885401 bytes, checksum: 676ec9c1c9823ae7accd5e51d3de1035 (MD5) Previous issue date: 2009 / Resumo: O café sempre foi sinônimo de progresso e contribuiu de maneira decisiva para a industrialização do Brasil sendo, ainda hoje, um dos seus produtos agrícolas mais importantes. A obtenção de informações precisas, em tempo hábil e com baixo custo, sobre a extensão e o rendimento da cultura, são instrumentos valiosos para um planejamento adequado da cultura no país. Dentre as técnicas que podem ser utilizadas, neste caso, o sensoriamento remoto é uma das que possuem um grande potencial de aplicação, principalmente considerando o aumento da disponibilidade de imagens de média resolução espacial e o advento das imagens de alta resolução espacial. Sendo assim, o objetivo geral do trabalho foi compreender as interações existentes entre os parâmetros biofísicos de cafezais e a resposta espectral registrada nas bandas de imagens dos satélites TM/LANDSAT e QUICKBIRD adquiridas em 24/01/2006 e 05/02/2006, respectivamente. Foram utilizados 30 talhões pertencentes a seis propriedades agrícolas, localizadas na região da Alta Mogiana, em São Paulo, entre os municípios de Ribeirão Corrente, Franca e Cristais Paulista. Os parâmetros biofísicos da cultura determinados a partir de dados de campo foram o espaçamento entre linhas e plantas, altura, IAF, diâmetro da copa, porcentagem de cobertura vegetal, rugosidade, variedade e biomassa. Foram utilizados valores de refletância real das bandas espectrais dos dois satélites e quatro índices de vegetação (NDVI, GVI, SAVI e RVI). Foi aplicado o teste de Tukey e realizadas análises de correlação, regressão e fatorial por componentes principais, utilizando os dados biofísicos e remotos disponíveis. Alguns parâmetros biofísicos não puderam ser estimados, mesmo com a melhoria da resolução espacial. Outros foram estimados (IAF, Biomassa e Altura) mesmo utilizando dados remotos de média resolução espacial. A análise de componentes principais permitiu separar plantios em produção, de áreas em formação, para as duas imagens, sendo que a associação dos parâmetros biofísicos "porcentagem de cobertura" e "densidade populacional" foi a principal responsável por estes resultados. Estes agrupamentos podem ser de grande utilidade na classificação automática de imagens. Apesar do avanço tecnológico proporcionado pelas imagens de alta resolução espacial, elas não se mostraram superiores a ponto de substituírem, mas complementarem as informações fornecidas pelas imagens de média resolução. / Abstract: Coffee has been synonymous of progress and has strongly contributed to the industrialization of Brazil. Nowadays, the coffee is still one of the most important Brazilian agricultural products. Precise, on time and low cost information about coffee area and yield are valuable tools for the crop planning in the country. For this purpose, remote sensing techniques show a great potential to be applied, especially considering the increased availability of medium spatial resolution images and the coming of high spatial resolution imagery. Thus, the main objective of this study was to understand the interactions between the biophysical parameters of coffee crops and the spectral response measured by the TM/LANDSAT and QUICKBIRD satellites spectral bands, acquired on 24/01/2006 and 05/02/2006, respectively. We used 30 coffee areas in six farms, located in the region of Alta Mogiana, in the State of São Paulo, between the municipalities Ribeirão Corrente, Franca e Cristais Paulista. The biophysical crop parameters determined from the field survey were the row and plants spacing, height, LAI, crown diameter, percentage of vegetation cover, roughness, variety and biomass. We used real values of reflectance from the spectral bands of both satellites and four vegetation indexes (NDVI, GVI, SAVI and RVI). Tukey test was applied and it was carried out the analysis of correlation, regression and factorial analysis through principal components by using the available remote and biophysical data. Some biophysical parameters could not be estimated, even with improved spatial resolution. Others were estimated (LAI, biomass and height), even using remote data of medium spatial resolution. The analysis of the main components allowed to separate crop lands in production and in formation in the two images. The combination of biophysical parameters "percentage of coverage" and "density" was the main responsible for these results. This technique can be very useful in the automatic classification of images. Despite the technological advances provided by the images of high spatial resolution, these images may not replace, but complement the information provided by medium-resolution images. / Doutorado / Planejamento e Desenvolvimento Rural Sustentável / Doutor em Engenharia Agrícola
119

Mapeamento de areas de cafe no municipio de Guaxupe/MG por meio de processamento digital de imagens Landsat / Coffee crop areas mapping in mountain relief through Principals Components Analysis

Nery, Luis Antonio 13 August 2018 (has links)
Orientador: Rubens Augusto Camargo Lamparelli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-13T09:46:25Z (GMT). No. of bitstreams: 1 Nery_LuisAntonio_M.pdf: 111375957 bytes, checksum: 05f2b3dc3fe0dece107d3e34a24a5a3e (MD5) Previous issue date: 2009 / Resumo: A importância econômica da produção brasileira de café no mercado mundial é notória e contribui com uma grande parcela na balança comercial de exportação do país. Minas Gerais se destaca como o centro da atual produção cafeeira no Brasil e tem na região sul do estado a grande concentração da lavoura de café (Coffea arabica), onde o seu cultivo é realizado em pequenas propriedades bastante dispersas pela região montanhosa. A necessidade de adequação da agricultura cafeeira por meio do planejamento, controle de custos e melhoria da produtividade, tem acelerado a procura por técnicas e ferramentas para a previsão da produção agrícola passando, necessariamente, pela localização e quantificação das áreas cultivadas. Neste contexto, o objetivo desta pesquisa foi avaliar o fornecimento de informações dos dados do sensor TM/Landsat 5 utilizando as técnicas de Análise por Principais Componentes (APC) e separação de classes de iluminação sobre as áreas de lavoura de café em região montanhosa. A área de estudo escolhida foi o município de Guaxupé/MG por conter uma forte lavoura cafeeira mantida sob um organizado sistema cooperativo. Foram utilizadas imagens dos satélites Landsat 7, Landsat 5 e do sensor MODIS para a aplicação das técnicas de processamento digital, para correção atmosférica e normalização radiométrica, visando a análise do cafeeiro nas datas de 15/08/2001, 05/12/2001 e 12/04/2002, que caracterizam os estágios fenológicos do cafeeiro como períodos de colheita (repouso e senescência dos ramos), florada e início do crescimento da gemas florais, respectivamente. Também foi utilizada uma máscara da área cafeeira obtida por método de interpretação visual extraído de imagens Ikonos. A utilização de um modelo digital de elevação gerado por imagens do sensor ASTER/TERRA possibilitou a aplicação da técnica de determinação do fator de iluminação, que consistiu na criação de classes de iluminação que contribuíram na identificação de áreas de lavoura e áreas de mata sombreadas pelo relevo. Dados de campo foram levantados para auxiliar na identificação da lavoura cafeeira, separadas pelas classes amostrais de café adensado e café adulto em função dos espaçamentos de ruas e linhas adotados no plantio. A Análise por Principais Componentes (APC) foi aplicada com o objetivo de reduzir a redundância dos dados obtidos das imagens orbitais de maneira a permitir a seleção de amostras de treinamento para a utilização em classificação supervisionada. Utilizando o método da Distância de Mahalanobis como classificador, as imagens nas datas selecionadas para a pesquisa, mostraram dados importantes quando comparados os resultados das classificações com a máscara da área de café extraída das imagens Ikonos do município. Os resultados dessas classificações foram validados por meio da determinação da Exatidão Global e coeficiente Kappa que mostraram os valores de EG= 0,78 e K= 0,40 para a imagem de 15/08/2001, EG= 0,81 e K= 0.29 para a imagem de 05/12/2001 e, EG= 0,76 e K= 0,24 para a data de 12/04/2002, confirmando que o período seco (maio até outubro) é favorável para a classificação do cafeeiro que, neste período está sob processo de colheita onde, a queda de folhas e remoção de frutos ocorre, diferenciando das outras coberturas do solo como as matas. Os maiores valores atingidos na validação dos dados ocorreram na classificação da imagem gerada pela composição dos resultados das três datas, atingindo valores de EG = 0,81 e Kappa = 0,56. O valor da área, quantificada como sendo da cultura do café, encontrado pelo método de soma dos resultados das classificações em cada data, produziu um valor 73,06 % do total de área quantificada na máscara de café, utilizada como referência. Neste sentido a metodologia se mostrou bem adequada na quantificação de áreas de café em relevo montanhoso. / Abstract: The economic importance of Brazilian coffee growing in the world market is notorious and makes up significant portion of the country's foreign trade exports. Minas Gerais stands out as the core of Brazilian coffee growing, with most of the planting areas (Coffea arabica) concentrated in the south, where it is grown in small plots widely spread throughout the hills. The need to adequate coffee agriculture by planning, cost control and productivity improvement has increased the search for techniques and tools for the prediction of agricultural production, necessarily involving the location and quantification of cultivated areas. In this context, the goal of this research has been to evaluate data from the TM/Landsat-5 remote sensor, providing information about coffee growing areas in hilly regions. The city of Guaxupé/MG/Brazil was chosen for this study due to its strong coffee growing, kept under an organized cooperate system. Images from the Landsat-7 and Landsat-5 satellites and from the MODIS sensor have been employed for the purpose of using digital processing tools for atmospheric correction and radiometric normalization, in order to analyze coffee crops in three dates: 08/15/2001, 12/05/2001 and 04/12/2002, characterizing phenological stages such as harvesting periods (rest and senescence of boughs), flowering and beginning of flower bud growing, respectively. The use of a digital elevation model generated from ASTER/TERRA sensor enabled the use of a lighting factor determination technique, consisting in the creation of lighting classes that contributed in the identification of crop areas and terrain-shadowed vegetated areas. Field data were gathered to help identifying coffee plantation separated by sample classes of dense coffee and adult coffee as a function of the spacing of the field foods and lines used in planting. PCA (Principal Component Analysis) was applied in order to reduce the redundancy of the data obtained from orbital imaging in a way that allows the selection of training samples for use in supervised classification. Using the Mahalanobis Distance as a classifier, the images in the selected dates showed highly positive result when the classification was compared to the coffee area mask extracted from Ikonos images. The results of these classifications were validated through the determination of Global Accuracy and Kappa Index, which showed values of GA= 0.78 and K= 0.40 for the 08/15/2001 image, GA= 0.81 and K= 0.29 for the 12/05/2001 image, and GA= 0.76 and K= 0.24 for 04/12/2002, confirming that the dry season (May through October) is favorable for the classification of coffee, which is under the harvesting process in this period, during which the falling of leaves and remotion of fruit separates it from other ground cover such as vegetation. The spectral data obtained from satellite imaging through digital processing have proven themselves adequate for the location of coffee-growing areas in hilly regions when aided by a digital elevation model. The value of the area as being coffee crop, calculated by sum of the areas found from each date classification, produced 73,06% of the agreement with coffee mask considered as a reference data. Due this the methodology showed very suitable to quantify coffee areas in hilly region. / Mestrado / Planejamento e Desenvolvimento Rural Sustentável / Mestre em Engenharia Agrícola
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Identificação e caracterização de cDNAs expressos diferencialmente e detecção de alterações metabolicas em folhas de cafeeiro inoculadas com Hemileia vastatrix / Identification and characterization of cDNAs differentially expressed and detection of metabolic alterations in coffee leavers inoculated with Hemileia vastatrix

Queiroz, Tania Marcia de 06 June 2007 (has links)
Orientador: Laura Maria Mariscal Ottoboni / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-09T07:40:24Z (GMT). No. of bitstreams: 1 Queiroz_TaniaMarciade_D.pdf: 1627218 bytes, checksum: 918b6b5965fc39fc4d4c34076a315249 (MD5) Previous issue date: 2007 / Resumo: A ferrugem alaranjada, cujo agente causal é o fungo Hemileia vastatrix Berk & Br., tem sido um dos principais problemas da cultura do cafeeiro em todas as regiões do mundo. Esta doença pode causar prejuízos de até 50% da produção. O fungo ataca todas as variedades de café, porém Coffee canephora apresenta cultivares resistentes, enquanto a maioria dos cultivares comerciais dentro da espécie Coffea arabica é suscetível à doença. Nesse trabalho foi feita a identificação e a caracterização de genes expressos diferencialmente em C. arábica cultivar Icatu Vermelho ¿ IAC 4045 (resistente ao agente da ferrugem). Para isso, foi utilizada a técnica de display diferencial de mRNA. A comparação entre os padrões de cDNAs nos géis permitiu o isolamento de cDNAs com expressão diferencial nos intervalos de 1 hora e 24 horas após a inoculação com o fungo. Alguns desses cDNAs foram clonados e seqüenciados. As seqüências obtidas foram comparadas com seqüências disponíveis no banco de dados do Genoma Café, sendo que oito cDNAs tiveram sua expressão confirmada e apresentaram similaridade com uma anexina, uma proteína M do fotossistema II, uma pirofosfatase prótoninorgânica vacuolar, um Citocromo P450, uma proteinase carboxil-terminal, uma proteína heat shock - HSP70, uma quinase C e uma proteína FIS1. Além da análise da identificação de genes com expressão diferencial, foi feita também uma análise das diferenças metabólicas em folhas de C. arabica cv. Icatu Vermelho - IAC 4045 e Mundo Novo - IAC 501 inoculadas com H. vastatrix. A técnica utilizada nas análises foi DRIFTS (diffuse reflectance infrared Fourier transform spectrometry ou espectroscopia no infravermelho por reflectância difusa com transformada de Fourier). Foram observados picos de reflectância proeminentes em regiões de números de onda 1075 'CM POT. ¿1¿, 1375 'CM POT. ¿1¿, 1555 'CM POT. ¿1¿, 1520 'CM POT. ¿1¿, 1150 'CM POT. ¿1¿ e 1645 'CM POT. ¿1¿. A análise de componentes principais demonstrou que houve uma discriminação entre Icatu Vermelho e Mundo Novo 48 horas após a inoculação e o teste de Tukey mostrou que para as regiões 1555 'CM POT. ¿1¿, 1520 'CM POT. ¿1¿ e 1645 'CM POT. ¿1¿ houve uma diferença significativa entre os cultivares a 5% de probabilidade / Abstract: The orange rust, caused by fungus H. vastatrix Berk & Br., has been the major problem of the coffee culture in all regions of the world. This disease can cause 50% damage in the plantation. The fungus attack all the coffee varieties, but C. canephora present resistant cultivars while the majority of the comercial cultivars into C. arabica is susceptible to disease. This experiment has the purpose of the identification and characterization of the differentially expressed cDNAs in C. arabica cultivar Icatu Vermelho (resistant to rust fungus). For this has been utilized mRNA differential display technique. The comparation between cDNAs in the display gels allowed the cDNAs isolation with differential expression in the intervals of 1 hour and 24 hours after inoculation of leaves with fungus. Some cDNAs were cloned and sequenced. The sequences were compared in Coffee Genome data bank and eight cDNAs had the expression confirmed and present similarity with a annexin, photosystem II M protein, a vacuolar proton inorganic pyrophosphatase, a cytochrome P450 family, a carboxyl-terminal protease, a heat shock 70 kDa protein, and a FIS1 protein. Beyond differential expression of the genes analysis, we also analysed the metabolic differences in C. arabica cultivars Icatu Vermelho (IAC 4045) and Mundo Novo (IAC 501) leaves inoculated with H. vastatrix. The technique utilized was DRIFTS (diffuse reflectance infrared Fourier transform spectrometry). Principal Component Analysis demonstrate there were a discrimination between Icatu Vermelho and Mundo Novo 48 hours after inoculation and Tukey Test showed to the regions 1555 'CM POT. ¿1¿, 1520 'CM POT. ¿1¿, 1645 'CM POT. ¿1¿ there were significative difference between cultivars to 5% of probability / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural

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