In 2011 Storvreta IK installed two solar collector systems in order to reduce the club’s electricity demand for domestic hot water. However, electricity use from 2012 to 2015 shows that the expected reduction in the electricity demand has not occurred. This project investigates the solar collector systems and the heat demand of Storvreta IK’s buildings in order to explain the “failure” in electricity savings. The results of the simulations show that the heat production of the solar collectors is lower than Storvreta IK’s expectations. This could be explained by that the domestic hot water is not used as much as Storvreta IK thought and the system is therefore over-dimensioned for their need. The rebound effect could be another reason to why the electricity saving is lower than expected.

Norton Simon was a unique collector because he let passion guide his collecting interests, but he controlled his passion by making his purchases based on smart economic decisions bolstered by years of experience in successful business negotiations. The Norton Simon Museum, today in Pasadena, California, displays the eccentric collectors life work as he created one of the greatest and most recognized collections on the west coast. By examining the progression and establishment of Norton Simon Inc., alongside the creation of the Norton Simon Art Foundation, multiple parallels can be drawn between Simons’ unique approach to business and the application of his unorthodox techniques to his purchases in the art world – Norton Simon’s “two hats”.

Thesis (M.A.)--University of the Witwatersrand, Faculty of Humanities, History of Arts, 2013 / This report examines the collecting practices of the private collector of South African art, situated in South Africa, and considers the way in which the act of collecting influences both the contemporary market and the construction of the art historical canon. The report questions the contribution made to the South African art world by collecting practices and considers what is involved in the collecting of fine art. I discuss the collector in relation to Sylvester Ogbechie’s (2010) notion of cultural brokerage; I examine notions of both public and private through the writings of Michael Warner (2002); and I consider what makes into one a collector, with reference to Thomas G. Tanselle’s (1998) text A Rationale of Collecting, while engaging several other sources. The report continues with a comparison between international collectors, with a focus on the ways in which they contribute to what becomes and remains relevant, as well as discussing some local collectors. I conclude with an examination of the way in which auction houses have played a seminal role in the establishment of the canon in South Africa, and the role of the collector in relation to this system. In summary, this paper examines the ways in which the private collector of South African art has a great influence on what is perceived as relevant to the canon, to culture and to art history.

This bachelor thesis evolves around the topic of art collectors as a phenomenon throughout different centuries. Ernest Thiel was a Swedish art collector at the turn of- and early 20th- century. Tom Böttiger is a contemporary art collector who acquired his first artwork during the 80’s. Both collectors are more like than alike, which points to and enforces certain common stereotypes as to whom could be a collector and what kinds of collectors exist. This thesis compares those two collectors from different times, from an art collectors perspective. The thesis concluded that collectors often bring upon themselves to act as patrons for the artists, both by promoting and purchasing their works, but also by aiding them financially.

Este trabalho apresenta um modelo inovador de coletor solar plano, com placa absorvedora fabricada por Estampagem Incremental e Soldagem FSW (Friction Stir Welding). Esta placa absorvedora é constituída de duas chapas de alumínio AA1200-H14 com espessura de 1 mm, estampadas e soldadas em simetria, a fim de que na união das chapas sejam deixados canais para passagem de água. Neste estudo foi realizada a caracterização do material por Ensaio de Tração e Ensaio Nakajima. Para determinação dos parâmetros de Estampagem Incremental foram realizados 16 experimentos com ferramenta de diâmetro df = 9,5 mm, variando a rotação de N = 50 rpm a 800 rpm e o incremento vertical de Δz = 2 mm a 0,2 mm, mantendo o avanço em = 250 mm/min. E também foram realizados 3 experimentos com ferramenta df = 22 mm, variando o incremento vertical de Δz = 2 mm a 0,5 mm, mantendo a rotação em N = 50 rpm e o avanço em = 250 mm/min. Para determinação dos parâmetros de Soldagem FSW foram realizados 4 experimentos com ferramenta de ombro de diâmetro 8 mm e pino roscado M3x0,5, mantendo a rotação em N = 1500 rpm e variando o avanço entre = 100 mm/min a 400 mm/min. Em seguida foi fabricado um protótipo de placa absorvedora de coletor solar com área de 0,12 m². Nos experimentos realizados foi constatado que é possível obter maiores deformações na Estampagem Incremental do que na Estampagem Convencional e que as deformações são mais elevadas quando se utiliza menores diâmetros, maiores rotações e menores incrementos verticais da ferramenta. Na Soldagem FSW não foi constatada influência na qualidade do cordão de solda em relação à variação do avanço da ferramenta. Neste estudo também se verificou que é possível fabricar protótipos de placas absorvedoras de coletores solares pelos processos de Estampagem Incremental e Soldagem FSW. No entanto, para coletores em tamanho comercial, novos estudos são necessários para melhorar a forma de fixação das chapas durante a Soldagem FSW. / This work presents an innovative model of flat plate solar collector, with absorber plate manufactured using Incremental Sheet Forming (ISF) and Friction Stir Welding (FSW). This absorber plate consists of two AA1200-H14 aluminum sheets with a thickness of 1 mm, stamped and welded in symmetry, in order to leave channels for the passage of water. In this study the characterization of the material by Nakajima Test and Traction Test was performed. In order to determine the parameters of ISF, 16 experiments were performed with a tool of diameter df = 9.5 mm, varying the rotation speed of N = 50 rpm at 800 rpm and the step down of Δz = 2 mm to 0.2 mm, maintaining the feed rate at = 250 mm/min. Also, 3 experiments with tool df = 22 mm were performed, varying the step down of Δz = 2 mm to 0.5 mm, maintaining the rotation speed at N = 50 rpm and the feed rate at = 250 mm/min. For determination of FSW parameters, 4 experiments with 8 mm diameter shoulder tool and M3x0.5 pin were performed, maintaining the rotation speed at N = 1500 rpm and varying the feed rate from = 100 mm/min to 400 mm/min. A prototype solar collector absorber plate with a 0.12 m² area was then manufactured. In the experiments carried out, it was found that it is possible to obtain greater deformations in the ISF than in the Conventional Stamping and that the deformations are higher when using smaller diameters, higher rotations and smaller step downs of the tool. In FSW, no influence was observed in the quality of the weld bead in relation to the variation of the tool feed rate. In this study it was also verified that it is possible to manufacture prototypes of solar collector absorber plates by the processes of ISF and FSW. However, for commercial size collectors, further studies are needed to improve the way the plates are fixed during FSW.

Made available in DSpace on 2016-10-13T14:10:22Z (GMT). No. of bitstreams: 1 Wagner Alexandre Silva.pdf: 3888345 bytes, checksum: edc97b19e24930dc64474d55a9e1598b (MD5) Previous issue date: 2015-03-27 / This thesis analyzes the sign production of bishoujo statues and dioramas, under the perspective of Communication, Consumption and Memory in the current context, and how important is its collecting for the maintenance of the records of the fans memory. This thesisrefers to the hybridization of pop culture and highlights its hybridization with the Japanese pop culture, allowing the conception of a socioeconomic and cultural individual emerged in this context, named as fan-collector. Through the testimonials of fans and collectors and the analysis of images and illustrations, also grounded by the studies of the theories of the concepts of intellectuals and mass culture presented by Edgar Morin (2002); of fans, brought by Cornell Sandvoss (2005); of collectors and collecting, discussed by Walter Benjamin (2009) and Jean Baudrillard (2008); of memory, conceived by Iuri Lotman (1981) and Andreas Huyssen (2000); of shôjo mangá and Japanese pop culture, established by Sônia Luyten (2015), Yuji Gushiken (2013) and Michiko Okano (2015); of cosplay, developed by Mônica Nunes (2014;2015); of communication and consumption, conceived by Grant McCracken (2003); of identity, proposed by Manuel Castells (2000); and hybrid cultures, presented by Néstor García Canclini (2013), and other authors related to the study developed by this thesis, we sought to assess how the consumption of bishoujo statues and dioramas has contributed in fan and collector memories operation, in the cosplay scene recoding and in the identity construction of the fan-collector. / Esta dissertação analisa a produção sígnica das estátuas e dioramas bishoujo, sob a ótica do campo da Comunicação, do Consumo e da Memória no contexto atual, e o quão importante é o seu colecionismo para a manutenção dos registros de memória do fã e do colecionador. O trabalho se refere à hibridização da cultura pop e destaca a ocorrida com a cultura pop japonesa, de modo a permitir conceituar um ator sócio-econômico-social surgido, neste contexto, denominado como fã-colecionador. Por intermédio de depoimentos de fãs e colecionadores e da análise de imagens e ilustrações, e fundamentado teoricamente pelos conceitos de cultura de massa e imaginários apresentados por Edgar Morin (2002); de fãs, trazidos por Cornell Sandvoss (2005); de colecionador e coleção, discutidos por Walter Benjamin (2009) e Jean Baudrillard (2008), de memória, concebidos por Iuri Lotman (1981) e por Andreas Huyssen (2000), de shôjo mangá e cultura pop japonesa, demonstrados por Sônia Luyten (2005), Yuji Gushiken (2013) e Michiko Okano (2015), de cena cosplay, desenvolvido por Mônica Nunes (2014; 2015); de comunicação e consumo, elaborados por Grant McCracken (2003); de identidade, proposto por Manuel Castells (2000); e culturas híbridas, apresentados por Néstor García Canclini (2013), e demais autores ligados ao estudo desenvolvido, buscou-se avaliar como o consumo das estátuas e dioramas bishoujo tem contribuído na operação de memórias do fã e do colecionador, na recodificação da cena cosplay e na construção identitária do fã-colecionador.

Entre outubro de 2009 e dezembro de 2012, foi realizado estudo no Laboratório de Hidrologia Florestal Walter Emmerich (L.H.F.W.E.), para avaliar o potencial hidrológico dos nevoeiros e a precipitação oculta em ambiente de Floresta Ombrófila Densa Montana, na Serra do Mar, em Cunha, a leste do Estado de São Paulo. Os objetivos específicos da pesquisa foram: 1) avaliar o desempenho de coletores de água de nevoeiro; 2) verificar o potencial de coleta de água de nevoeiro no laboratório; 3) analisar o potencial de coleta de água de nevoeiro em três setores da microbacia experimental D; 4) averiguar a distribuição espacial e temporal de ocorrência dos nevoeiros na microbacia D e 5) estimar a contribuição da precipitação oculta na floresta da microbacia D. Para alcançar os três primeiros objetivos foram usados coletores passivos tipo harpa, nas formas cilíndrica e plana. Para estudar a distribuição de nevoeiros, foram feitas observações diárias de três referências visuais situadas a distâncias conhecidas no interior da microbacia D. O método da medição da precipitação efetiva foi empregado para estimar a precipitação oculta na floresta. Sobre a distribuição espacial e temporal da ocorrência de nevoeiros na microbacia D, os resultados mostraram que os episódios de nevoeiro foram mais comuns à tarde, como decorrência da brisa marítima proveniente do Oceano Atlântico. Para 61,3% do tempo, em média, foi observada a presença de nevoeiro em algum setor da microbacia, com a ocorrência dos nevoeiros diminuindo de montante para jusante da área. No que concerne ao desempenho dos equipamentos, a média de coleta diferiu de coletor para coletor, exceto entre o coletor cilíndrico descoberto e o coletor plano, que interceptaram mais água que os coletores cilíndricos cobertos. O coletor plano foi o único a interceptar água em todos os episódios amostrados. Sobre o potencial de coleta de água de nevoeiros no laboratório, concluiu-se que é reduzido e resulta da combinação de três fatores: a grande ocorrência de nevoeiros de radiação, a curta duração dos ix episódios dos nevoeiros orográficos e a baixa intensidade dos ventos na região. No que concerne ao potencial de coleta de água de nevoeiro em três setores da microbacia D, árvores localizadas próximas aos coletores funcionaram como obstáculo à livre circulação dos nevoeiros orográficos, induzindo os coletores a interceptar exíguos volumes de água. Considerando apenas os eventos de nevoeiro sem chuva, a precipitação oculta foi de 2,3 mm, correspondendo a 0,12% da precipitação pluviométrica anual. Para os eventos de chuva com a presença de nevoeiro, a precipitação oculta gerou um total de 5,1 mm de água adicional ao piso da floresta, correspondendo a 0,27% da precipitação pluviométrica. Concluiu-se que a precipitação oculta na floresta não é um processo importante para a entrada de água na microbacia D. / Between October 2009 and December 2012 a study was conducted at the Walter Emmerich Hydrologic Laboratory (LHFWE) to assess the hydrological potential of fog and occult precipitation in the Montane Dense Ombrophilous Forest environment located in the Parque Estadual da Serra do Mar - Núcleo Cunha, east of the State of São Paulo, Brazil. The specific multiple objectives of the research were: 1) evaluate the performance of passive fog collectors, 2) evaluate the potential for collecting fog water in the laboratory, 3) evaluate the potential of collecting fog water in three sectors of experimental catchment \"D\", 4) determine the spatial and temporal distributions of fog occurrence in catchment \"D\", 5) estimate the contribution of occult precipitation in the rainforest in catchment \"D\". To achieve the first three objectives, cylindrical and flat harp collectors were used. To study the spatial and temporal distributions of fog occurrence, we made daily observations of three visual references located at known distances within the catchment. Net precipitation was measured and used to estimate the occult precipitation in the rainforest. Regarding the spatial and temporal distributions of fog occurrence, the results showed that episodes of fog were more common in the afternoon as a result of the sea breeze from the Atlantic Ocean. For 61.3% of the time on average, we observed the presence of fog in some sector of the catchment, with its occurrence decreasing in areas located from upstream to downstream. Concerning the comparison of the performance of the collectors, the average volume of water collected differed from collector to collector, except between cylindrical collector uncovered and flat collector, which captured more water than the cylindrical collectors covered to prevent rainwater input. The flat collector was the only gauge to intercept water in all episodes. The high incidence of fog radiation, the short duration of orographic fog, and the low intensity of winds combined to reduce the potential for harvesting fog water in the laboratory. Regarding the potential for collecting fog water in three sectors of the catchment \"D\", xi trees located next to collectors operated as an obstacle to the free movement of orographic fog inducing gauges to intercept exiguous volumes of water. Considering only fog, but no rain, occult precipitation was 2.3 mm, corresponding to 0.12% of annual rainfall. For rainfall events with the presence of fog, occult precipitation generated a total of 5.1 mm of additional water to the floor of the forest, equivalent to 0.27% of the rainfall. It was therefore concluded that occult precipitation in rainforest did not significantly contribute to water entering catchment \"D\".

O problema de investigação que originou esta tese foi o questionamento acerca de quais competências devem constituir o perfil de empreendedores dedicados à gestão de empreendimentos populares solidários. O estudo foi realizado com participantes de cooperativas de coleta e tratamentos de resíduos sólidos, buscando identificar, descrever e analisar as competências que melhor contribuem para que essas pessoas consigam dedicar-se aos processos de trabalho próprios dessas cooperativas, mas também exercerem funções administrativas e gerenciais que são essenciais à sobrevivência do empreendimento. Essas cooperativas integraram o Projeto de Implantação da Incubadora de Empreendimentos Solidários de São Bernardo do Campo, o que permitiu analisar se e como esse processo de incubação contribuiu para o desenvolvimento do perfil de competências desses empreendedores. O objeto de pesquisa dessa investigação foram os catadores participantes dessas cooperativas de coleta e tratamento de resíduos sólidos recicláveis que são acompanhadas pelo projeto, na região do Grande ABC Paulista. Foi realizada uma pesquisa de caráter exploratório e descritivo, com a utilização do método qualitativo do estudo de caso, com análise documental, entrevistas e a técnica etnográfica da observação participante. A problemática da pobreza, a desigualdade social e as iniciativas públicas, privadas e do terceiro setor visando criar oportunidades de trabalho e renda para os mais pobres no Brasil, constituem o pano de fundo dessa pesquisa. Os resultados apontam que as organizações solidárias necessitam das competências individuais para sua sustentação e que essas competências podem ser desenvolvidas em processos de incubação como esse que é apresentado no presente estudo. Os empreendimentos solidários são organizações que não possuem como objetivo estratégico o lucro e sim a remuneração regular daqueles que neles trabalham como associados e o fortalecimento das relações intragrupais com o desenvolvimento da confiança e da cooperação. Nesse sentido, para compreender esses empreendimentos e o desempenho de seus integrantes é necessário considerar duas dimensões da sua dinâmica, o empreendedorismo e a solidariedade que se sustentam sobre as competências das pessoas que lá trabalham. / The research problem that gave rise to this thesis was the question about which competencies should be the profile of entrepreneurs dedicated to the management of popular solidarity enterprises. The study was conducted with participants from the collection and treatment of solid waste cooperatives , seeking to identify, describe and analyze the capacities that better contribute to that these people are able to devote himself to the work processes of these cooperatives , but also exercise administrative and managerial functions that are essential to the survival of the enterprise . These cooperatives have integrated the Project Implementation of the Entrepreneurial Incubator Solidarity of São Bernardo do Campo , which allowed us to analyze if and how this incubation process contributed to the development of the competencies profile of these entrepreneurs. The research object of this investigation were the participants collectors such collection and processing of recyclable solid waste cooperative that is accompanied by the project, in the Greater ABC Paulista region. An exploratory and descriptive research, using the qualitative method of case study to document analysis, interviews and ethnographic technique of participant observation was conducted. The problems of poverty, social inequality and public, private and third sector initiatives aimed at creating job opportunities and income for the poorest people in Brazil, is the background of this research. The results indicate that the solidarity organizations require individual competences for their support and that these capacities can be developed in incubation processes like this that is presented in this study. The solidarity enterprises are organizations that do not have as a strategic motive the profit, but the regular remuneration of those who work in them as associates and strengthening of intragroup relationships with the development of trust and cooperation. Accordingly, to study them is necessary to consider a dimension of entrepreneurship and other associations of which they sustained on the skills of the people working there.

Biosensors are used for the detection of a range of analytes for applications in healthcare, food production, environmental monitoring and biodefence. However, many biosensing platforms are large, expensive, require skilled operators or necessitate the analyte to be labelled. Direct electrochemical detection methods present a particularly attractive platform due to the simplified instrumentation when compared to other techniques such as fluorescence-based biosensors. With modern integrated circuit capabilities electrochemical biosensors offer greater suitability for monolithic integration with any necessary signal processing circuitry. This thesis explores micro- and nanogap devices for both redox cycling and dielectric spectroscopy sensing mechanisms. By using two electrodes with interelectrode separation down to distances in the micro- and nanometre scale, several benefits can be realised. Firstly the close proximity of the two electrodes significantly reduces the interdiffusion time. This allows an electroactive species to be rapidly shuttled across the gap and switched between reduced and oxidised states. The result is feedback amplification of the amperometric response, increasing the signal. The second benefit is that the screening effect caused by electric double layers at the electrode–electrolyte interface is reduced due to the electric double layers occupying a larger fraction of the sensing volume. This significantly improves the sensor suitability for dielectric spectroscopy by increasing the potential drop across the biolayer. These two sensing mechanisms are demonstrated using a large area dual-plate microgap device for the detection of two different analytes. Utilising the first mode, detection of cysteine–cystine, an important redox couple involved in the signalling mechanism for the regulation of protein function, interaction and localisation is shown. The microgap device is then used for dielectric spectroscopy sensing of a mannose-specific uropathogenic Escherichia coli strain whilst also demonstrating the effect of ionic concentration on the capacitive response. The response of these devices is highly dependent on the interelectrode separation as well as the surface area of the electrodes. However, fabrication of large-area nanogap devices presents a significant challenge. This meant that careful optimisation and the development of novel techniques was necessary. This work reports the design, fabrication and characterisation of both a vertical and a horizontal coplanar large area nanogap device. The vertical nanogap device is fabricated using an inductively-coupled plasma reactive ion etching process to create a channel in a silicon substrate. A lower electrode is then optically patterned in the channel before anodically bonding a second identical electrode patterned on glass directly above. The horizontal nanogap device uses a different approach, utilising a state-of-the-art electron-beam lithography system to create a long serpentine nanogap with passivation to reduce fringing effects. The design allows the electron-beam lithography step to be substituted with nanoimprint lithography to reduce cost and improve throughput. Both of these devices have integrated microfluidic channels and provide a capacity for relatively high-throughput production.

Submitted by Maicon Juliano Schmidt (maicons) on 2015-07-08T14:09:52Z No. of bitstreams: 1 Daniel dos Santos Silva.pdf: 1207479 bytes, checksum: a37801e7a4a9fabd110fb80d5c179a85 (MD5) / Made available in DSpace on 2015-07-08T14:09:52Z (GMT). No. of bitstreams: 1 Daniel dos Santos Silva.pdf: 1207479 bytes, checksum: a37801e7a4a9fabd110fb80d5c179a85 (MD5) Previous issue date: 2012-01-31 / Nenhuma / O uso da energia solar, como alternativa energética renovável, tem tomado um destaque fundamental no cenário mundial. Em especial, esse tipo de energia utilizado para aquecimento de água, tanto para uso doméstico como industrial representa um mercado mundial com crescimento em torno de 15% ao ano. No Brasil, esse crescimento deve-se, principalmente, aos programas habitacionais patrocinados pelo governo federal, além dos apelos cada vez mais fortes no sentido de buscar-se uma sustentabilidade energética e de economia através da diminuição do consumo de eletricidade e gás. Um sistema de aquecimento de água com energia solar é composto basicamente por coletor e reservatório térmico. Esses dois componentes representam quase a totalidade dos custos de instalação e isso ocorre principalmente em função dos materiais utilizados (cobre, alumínio e aço inoxidável) e dos processos de fabricação utilizados. Uma das formas para reduzir esses custos é a utilização de outros materiais mais baratos para a confecção de coletores e reservatórios e também de novos processos, mais ágeis e autômatos.Para contribuir com a solução desse problema, esse trabalho apresentará o desenvolvimento de uma ferramenta computacional que facilite a avaliação do rendimento térmico de diferentes composições de coletores solares de placa plana. Essa ferramenta foi desenvolvida sobre a plataforma EES (Engineering Equation Solver), pela sua facilidade de implementação, disponibilidade de funções de propriedades térmicas de fluidos, materiais e de escoamento. O programa segue um modelamento matemático baseado na teoria de Hottel-Bliss_Whillier e permite a entrada de dados relacionados aos parâmetros construtivos do coletor, como diâmetro dos tubos e espaçamento, espaçamento absorvedor-cobertura, material dos tubos, material da placa coletora e espessuras, material da cobertura e espessuras de isolamento, além de variáveis ambientais. Como dados de saída o programa fornece o desempenho térmico do coletor, calor útil, perdas térmicas, temperatura de estagnação, entre outros dados fundamentais de projeto. Os modelos matemáticos adotados na construção do programa foram validados através do confronto dos resultados calculados com dados obtidos experimentalmente em testes realizados pelo Test Center for Thermal Solar Systems do Fraunhofer Institut Solare Energie Systeme e pelo Institut für Thermodynamik und Wärmetechnik. Após a validação, a ferramenta é utilizada para avaliar o rendimento térmico de coletores com outros materiais construtivos, características óticas e termodinâmicas e também aspectos construtivos como a otimização do espaçamento de tubos, distanciamento entre cobertura e placa coletora, entre outros apresentados no capítulo quatro. / The use of solar energy as an alternative renewable energy, has taken a key highlight in the scene in different parts of the world. In particular, this type of energy used for heating water for domestic use becomes for a growing world market, mainly due to housing programs sponsored by the federal appeals beyond the increasingly strong in the sense of trying to achieve a sustainable energy and economy by reducing the consumption of electricity and gas. A system for heating water with solar energy is basically composed of collector and storage tank. These two components account for almost the entire cost of installation and this is mainly due to the materials (copper, aluminum and stainless steel) and the manufacturing processes used. One way to reduce these costs is the use of other cheaper materials for the manufacture of collectors. and reservoirs as well as new processes, more agile. To contribute to solving this problem, the present study the development of a software tool that facilitates the evaluation of the thermal efficiency of different compositions of flat plate solar collectors. This tool was developed on the platform EES (Engineering Equation Solver) for its ease of implementation, availability of functions of the thermal properties of fluids, materials and marketing.the program follows a mathematical model based on the theory of Hottel-Bliss_Whillier and allows entry of data related to the construction parameters of the collector, such as pipe diameter and spacing, spacing absorber-cover, the pipe material, the absorber material and thickness of material coverage and thickness of isolation and environmental variables. As output data the program provides the thermal performance of the collector, useful heat, thermal losses, stagnation temperature, and other fundamental data design.the mathematical models adopted in the construction of the program were validated by comparing the calculated results with data obtained experimentally by renowned research centers in Germany, as test center for thermal solar systems of Fraunhofer Institut Solare Systeme and Institut für Energie und Wärmetechnik Thermodynamik. After validation, the tool is used to evaluate the thermal performance of collectors with other building materials, optical characteristics and thermodynamic aspects of construction as well as the optimization of the spacing tubes, distance between absorber plate and cover, among others presented in chapter four.