934 resultados para Activator appliances
Resumo:
Emissions from residential combustion appliances vary significantly depending on the firing behaviours and combustion conditions, in addition to combustion technologies and fuel quality. Although wood pellet combustion in residential heating boilers is efficient, the combustion conditions during start-up and stop phases are not optimal and produce significantly high emissions such as carbon monoxide and hydrocarbon from incomplete combustion. The emissions from the start-up and stop phases of the pellet boilers are not fully taken into account in test methods for ecolabels which primarily focus on emissions during operation on full load and part load. The objective of the thesis is to investigate the emission characteristics during realistic operation of residential wood pellet boilers in order to identify when the major part of the annual emissions occur. Emissions from four residential wood pellet boilers were measured and characterized for three operating phases (start-up, steady and stop). Emissions from realistic operation of combined solar and wood pellet heating systems was continuously measured to investigate the influence of start-up and stop phases on total annual emissions. Measured emission data from the pellet devices were used to build an emission model to predict the annual emission factors from the dynamic operation of the heating system using the simulation software TRNSYS. Start-up emissions are found to vary with ignition type, supply of air and fuel, and time to complete the phase. Stop emissions are influenced by fan operation characteristics and the cleaning routine. Start-up and stop phases under realistic operation conditions contribute 80 – 95% of annual carbon monoxide (CO) emission, 60 – 90% total hydrocarbon (TOC), 10 – 20% of nitrogen oxides (NO), and 30 – 40% particles emissions. Annual emission factors from realistic operation of tested residential heating system with a top fed wood pelt boiler can be between 190 and 400 mg/MJ for the CO emissions, between 60 and 95 mg/MJ for the NO, between 6 and 25 mg/MJ for the TOC, between 30 and 116 mg/MJ for the particulate matter and between 2x10-13 /MJ and 4x10-13 /MJ for the number of particles. If the boiler has the cleaning sequence with compressed air such as in boiler B2, annual CO emission factor can be up to 550 mg/MJ. Average CO, TOC and particles emissions under realistic annual condition were greater than the limits values of two eco labels. These results highlight the importance of start-up and stop phases in annual emission factors (especially CO and TOC). Since a large or dominating part of the annual emissions in real operation arise from the start-up and stop sequences, test methods required by the ecolabels should take these emissions into account. In this way it will encourage the boiler manufacturers to minimize annual emissions. The annual emissions of residential pellet heating system can be reduced by optimizing the number of start-ups of the pellet boiler. It is possible to reduce up to 85% of the number of start-ups by optimizing the system design and its controller such as switching of the boiler pump after it stops, using two temperature sensors for boiler ON/OFF control, optimizing of the positions of the connections to the storage tank, increasing the mixing valve temperature in the boiler circuit and decreasing the pump flow rate. For 85 % reduction of start-ups, 75 % of CO and TOC emission factors were reduced while 13% increase in NO and 15 % increase in particle emissions was observed.
Resumo:
As últimas décadas têm apresentado significativas mudanças no cenário intercapitalista mundial. Especialmente após a popularização internacional das filosofias e técnicas japonesas de gestão, partindo do Sistema Toyota de Produção, muitos estudos e metodologias têm sido desenvolvidos na busca da racionalização dos processos produtivos. Basicamente estes estudos foram centrados nas características da indústria de forma, vale dizer, bens de capital e bens duráveis de consumo. Neste sentido, surge um natural questionamento sobre a aplicabilidade destes conceitos e técnicas a outros tipos de processos produtivos, especialmente no caso da indústria de propriedade contínua, muitas vezes identifica da como indústria de transformação (incluindo refino de petróleo, petroquímica, papel e celulose, energia elétrica e outras), pelas características específicas apresentadas pela mesma. Assim, a presente dissertação analisa diferentes metodologias desenvolvidas para a indústria de forma, avaliando a possibilidade de aplicação de seus conceitos à indústria de propriedade contínua. Posteriormente, desenvolve um modelo analítico mais apropriado à realidade e característica deste tipo de indústria. A seguir, baseado nas conclusões do modelo analítico desenvolvido, estabelece os conceitos básicos de um modelo de gestão dos processos produtivos da indústria de propriedade contínua. Finalizando, são apresentadas as conclusões relativas à aplicação das diferentes metodologias, e em especial dos modelos desenvolvidos, à indústria de propriedade de produção contínua.
Resumo:
Bolsa Família is the major brazilian conditional cash transfer program. It provides money to poor families contingent on investments in human capital, such as sending children to school or bringing them to health centers. This work aims to investigate if this program, in its normative structure, can be considered an appropriate policy of income redistribution and if it is able, appliances of the Welfare State model in the brazilian society and to approach the program in two different ways: as an alternative to more traditional social assistance programs and as a demand-side complement to the supply of other social needs. We will work on the thesis that the program by itself can not provide vulnerable populations with enough means to overcome poverty and to participate effectively on the market. According to this assumption, this paper is going to consider the reasons why tackling income necessary, along with the program, that the Government - in both federal and local spheres shall place major investments in critical areas like education and health.
Resumo:
Esta dissertação é um estudo de caso sobre aprendizagem tecnológica que, considerando as evidências empíricas descritas no Capítulo 6 e à luz da Tabela 3.1, procurou identificar a trajetória de acumulação de competência tecnológica da Enxuta Industrial Ltda., ao longo do período estudado (1980 - 2000), para as funções tecnológicas de investimentos (decisão e controle sobre a planta e engenharia de projetos), de processos e organização da produção, de produtos e de equipamentos. Para construir a estrutura de competências tecnológicas para a indústria de eletrodomésticos foi utilizada a estrutura desenvolvida por Figueiredo (2000). Por outro lado, considerando as evidências empíricas descritas no Capítulo 7 e à luz da Tabela 3.2, procurou-se identificar a influência dos processos de aprendizagem utilizados pela empresa sobre a sua trajetória de acumulação de competência tecnológica. Os processos de aprendizagem são avaliados à luz de quatro características chave: variedade, intensidade, funcionamento e interação, a partir do uso da estrutura desenvolvida por Figueiredo (2000). Este estudo verificou que o modo e a velocidade de acumulação de competência tecnológica na Enxuta Industrial Ltda. foram influenciados pelos processos e mecanismos de aprendizagem usados para adquirir conhecimento tecnológico e convertê-lo em organizacional. Estes processos e mecanismos de aprendizagem propiciaram a empresa alcançar uma maior velocidade na acumulação de capacidades tecnológicas, quando de sua entrada na indústria de eletrodomésticos, o que proporcionou alcançar o desenvolvimento tecnológico necessário para atuar nesta indústria. Porém, a simples incidência desses processos na empresa não garantiu uma implicação positiva para a acumulação de competência tecnológica. Pois, no período de 1991 - 1995, verificou-se a deterioração do funcionamento dos processos de aprendizagem utilizados na empresa, o que pode ter influenciada negativamente a repetibilidade e a interação daqueles processos. Isto parece ter contribuído para que a empresa falhasse em construir e acumular competências tecnológicas inovadoras naquele período. Através do uso de estrutura existente na literatura, aplicada a uma indústria diferente de estudos anteriores, esta dissertação sugere que deve existir um esforço organizado, contínuo e integrado para a geração e disseminação de conhecimento tecnológico na empresa, o que pode acelerar a acumulação de competências tecnológicas, desta forma propiciando à empresa a construção de uma trajetória de aproximação da fronteira de desenvolvimento tecnológica da indústria.
Resumo:
A crise financeira internacional de 2008 afetou tanto a economia dos Estados Unidos quanto a economia mundial. Assim, discutiu-se as origens da crise do “subprime”, em uma contextualização histórica e entendeu-se a repercussão dessa crise, com foco nas medidas anticíclicas brasileiras adotadas em nível setorial. Através de estudos econométricos que visavam avaliar a eficácia dessas medidas de políticas fiscal, monetária e creditícia, direcionadas aos setores automotivo, de construção civil e de móveis e eletrodomésticos, buscou-se entender a eficácia das medidas anticíclicas tanto como incentivo econômico, quanto na manutenção do nível de emprego, dois dos principais focos das políticas anticíclicas brasileiras. A análise empírica revelou, no lado do incentivo dos setores, que a política monetária expansionista não teve o efeito esperado em nenhum dos três setores testados, enquanto que as políticas creditícia e fiscal, também expansionistas, tiveram efeitos positivos sobre os setores em estudo. Pelo lado da eficácia na manutenção do emprego, as políticas fiscal e monetária foram eficazes para os três setores analisados, o que nos permite concluir que as medidas do governo tiveram alguma forma de eficácia. É importante ressaltar que se assumiu a premissa para as séries de IPI sobre o setor de móveis e eletrodomésticos e a série de desemprego, que não estavam disponíveis de forma específica, constituindo uma limitação ao trabalho.
Resumo:
Organizations are Complex systems. A conceptual model of the enterprise is needed that is: coherent the distinguished aspect models constitute a logical and truly integral comprehensive all relevant issues are covered consistent the aspect models are free from contradictions or irregularities concise no superfluous matters are contained in it essential it shows only the essence of the enterprise, i.e., the model abstracts from all realization and implementation issues. The world is in great need for transparency about the operation of all the systems we daily work with, ranging from the domestic appliances to the big societal institutions. In this context the field of enterprise ontology has emerged with the aim to create models that help to understand the essence of the construction and operation of complete systems; more specifically, of enterprises. Enterprise ontology arises in the way to look through the distracting and confusing appearance of an enterprise right into its deep kernel. This, from the perspective of the system designer gives him the tools needed to design a successful system in a way that’s reflects the desires and needs of the workers of the enterprise. This project’s context is the use of DEMO (Design and Engineering Methodology for Organizations) for (re)designing or (re)engineering of an enterprise, namely a process of the construction department of a city hall, the lack of a well-founded theory about the construction and operation of this processes that was the motivation behind this work. The purpose of studying applying the DEMO theory and method was to optimize the process, automating it as much as possible, while reducing paper and time spent between tasks and provide a better service to the citizens.
Resumo:
Two b-N-acetylhexosaminidases (F11 e F15) were purified from Echinometra lucunter gonads extracts. The purified enzymes were obtained using ammonium sulfate fractionation, followed by gel filtration chromatographies (Sephacryl S-200, Sephadex G-75 and Sephacryl S-200). The F11 fraction was purified 192.47 -fold with a 28.5% yield, and F15 fraction 85.41 -fold with a 32.3% yield. The molecular weights of the fractions were 116 kDa for F11 and 42 kDa for F15 using SDS-PAGE. In Sephacryl S-200, F15 was 84 kDa, indicating that it is a dimeric protein. When p-nitrophenyl-β-D-glycosaminide was used as substrate, we determined an apparent Km of 0.257 mM and Vmax of 0.704 for F11 and for F15 the Km was 0.235 mM and Vmax of 0.9 mM of product liberated by hour. Both enzymes have optimum pH and temperature respectively at 5.0 and 45 °C. The enzymes showed inhibition by silver nitrate, while the glucuronic acid was a potent activator. The high inhibition of F15 by N-etylmaleimide indicates that sulphydril groups are involved in the catalysis of synthetic substrate
Resumo:
The general objective of this study was to contribute to the understanding of the chemical evolution of fluids that percolate through carbonate rocks of the Jandaíra Formation. The oxidation and reduction conditions in which grains, source and cement were formed was investigated using the cathodoluminescence technique (CL). The study area is located in the west part of the Potiguar Basin (Fazenda Belém field) and Rosário Ledge (Felipe Guerra municipality, State of Rio Grande do Norte, Brazil). The analysis of thin sections of carbonate rocks under CL revealed that grains (allochemical or not) and diagenetic products (micritization, dolomitization, neomorphism and cementation) exhibit since absence of luminescence the various luminescence colors (yellow, orange, red, brown, and blue) in a variety of intensities. As pure calcite shows dark blue luminescence, the occurrence of different luminescence colors in calcite crystals suggest one or more punctual crystal defects such as free electron, free space and impurity. The dyeing of thin sections with alizarin and potassium ferrocyanide revealed the absence of ferrous carbonate in the different lithotypes of Jandaíra Formation. Therefore, the different colors and intensities of CL observed in these rocks are probably caused by the presence of ion activators such as Mn2+ and is not an activator/inhibitor combination. In the same way, the absence of luminescence is very probably caused by the absence of activator ions and not due to the low concentration of inhibitor ions such as Fe2+. The incorporation of Mn2+ in the different members of the Jandaíra Formation must have been controlled by the redox state of the depositional environment and diagenesis. Therefore, it is possible that the luminescent members have been formed (e.g.,ooids) or have been modified (gastropod neomorphism) under reduction conditions in the depositional environments, in subsurface during the burial, or, in the case of Rosario Ledge samples , during the post-burial return to surface conditions. As regards the sudden changes from low to moderate and to strong luminescence, these features should indicate the precipitation of a fluid with chemical fluctuations, which formed the frequent zonations in the block cement of the Rosario Ledge samples. This study suggests that the different intensities and colors of CL should be correlated with the Mn2+ and Fe2+ contents, and stable isotopes of samples to determine the salinity, temperature, pH e Eh conditions during deposition
Resumo:
The present work, based on the methodological principles of the Comprehensive Discourse Analysis, aimed, through the speech of twelve newly arrived students at the Pedagogy course of the Federal University of Rio Grande do Norte, to understand the moment students start university. It also aimed to analyze the relationship between the schools they were coming from and university entrance as well as the relationship between university and their new students. In the first part of the work, which focused on school knowledge, a comprehensive listening of the speeches of the students led primarily to a distinction, established by the students, between public and private schools, a distinction especially based on the view of superiority of private schools against public ones. The abovementioned interpretation is found in the discussion of the structural duality of Brazilian education which, historically, offers different pedagogical appliances among students of more priviledged social classes and those who come from lower levels of society. The overcome of this duality, aspired by the Brazilian Constitution of 1988, was stopped by the advent of a new economic model neoliberalism, which reinforced the differences between public and private when it prioritized the market on the economic, political and social relations, including educational projects. Impoverishment of public institutions and pauperization of the work of professors affected also the relationship between teachers and studens at the current institution. This is how the teacher becomes the greatest villain at the public management system. All of these references concerning differences in the quality of teaching at public and private schools, expressed by the students interviewed, however, were centered in the preparation for the entrance exam, called vestibular, thus showing a view that the relationship between the student and the school he came from is of a propedeutic kind and even so, reduced to a preparation for an entrance exam. In the second part of the work, which analyzed the relationship between newly arrived students and their university, it was noticed that the latter represents a whole new world. This world is seen as the change at the student´s social statute for now he is grown, takes more responsibilities and is socially respected. This change of attitude established by society and the discovery of a new world which requires more independence from the students, creates in them feelings of pride and fear and they feel insecure when it comes to making decision in the campus because now their decisions deliver a greater load of responsibility. This is when students understand they need to develop autonomy, which is seen, in this work, as the capacity to make conscious decisions. Nevertheless students expressed an understanding of autonomy as something that comes as a gift for those who enter university and not as a process that is constructed from social experiences. For these students, the need to be autonomous refers to the relationships with their teachers and the search for information. This search, however, is also related, according to interviews, to public school financial cuts, which penalize university, and to the lack of employers
Resumo:
A soil sample was taken from the top 0-20cm at Jaboticabal county, São Paulo State, Brazil, air dried, sieved to 5mm, and placed into pots (2700g per pot). Sewage sludge was air-dried, ground to 2mm, and thoroughly mixed to the top 0-10cm soil of each pot, which were irrigated with distilled water in a total volume equivalent to the last 30years average rainfall in the region. Sorghum was sowed 120days after sewage sludge incorporation and then the irrigation was made according to the plants' requirement. When the plants were about 10 cm high, they were thinned to two per pot. Soil samples (0-10, 10-20, and 20-30 cm depth) were obtained immediately after the incorporation of sewage sludge and at 30, 60, 120, and 170 days after, air dried, sieved to 2 mm and analyzed for organic matter (OM), pH (0,01 mol L-1 CaCl2), extractable P (resin), potassium (K), calcium (Ca), and magnesium (Mg), amylase and cellulase activity. Sewage sludge increased soil OM, pH, extractable phosphorus (P), K. Ca. amylase and cellulase activity, especially at the rate 16 t ha(-1). Organic matter, extractable P, K, Ca, Mg. and amylase activity were higher in the top 0-10cm, while pH was higher in the 20-30cm layer. Amylase activity was not affected by sampling depth. Organic matter, pH, extractable P. K, Ca, and Mg decreased during the experimental period. Amylase activity decreased until sorghum was sowed and increased afterwards. Cellulase activity increased until 90 days after sewage sludge application and then decreased. Sewage sludge used in the experiment should already contain some amylase activity or a substance that was a soil enzyme activator and also a substance that was an inhibitor of soil cellulase inhibitor. Sonic of the plant nutrients contained in sewage sludge, mainly P, did not migrate down the soil column. an indication that sewage sludge should be incorporated into the soil to improve nutrient bioavailability. Sorghum roots increased amylase activity but did not affect cellulase activity.
Resumo:
The fishing is made possible by the handiwork of a fisherman, not using appliances that achieve the same levels of industrial fishing productivity and not causing environmental impacts on fish stocks with the same intensity. The adoption of sustainability practices in this type of fishing has been requested for the achievement of environmental and socioeconomic improvements, since its production has been decreasing over the years and overfishing has led to reduced stocks also stand out environmental aggressions such as pollution. Thus, this research aims to analyze the interference of environmental aspects/impacts that permeate the activity performed by fisherman on the beach of Ponta Negra, Natal-RN, in order to propose recommendations for environmental sustainability. We used a methodology based on the ergonomic work analysis (WISNER, 1987; GUERIN, 2001; VIDAL, 2008) using techniques such as observational and interactional observation protocols, photographs, videos, conversational action, and listening to verbalizations. To understand the vulnerability of the environment in which the activity is carried fisherman and the interferences that it suffers, we used the study of environmental aspects/impacts (SÁNCHEZ 2008). As a result, it appears that from the observations located and reports raftsmen, changes in the sea, the search for new fishing grounds farther from the coast, reducing fishery production, waste generation and pollution of the workplace, and the difficulty in docking rafts, factors arising from the pressures both for society as Seen by fisherman, denoting the necessity of drawing up recommendations and actions proposed by management activity by promoting discussion among raftsmen and accountable institutions, and training through workshops on environmental education, aiming to positive changes in the activity fisherman from Ponta Negra and the environment in which raftsmen are inserted in order to seek a sustainable activity, preserving its characteristics
Resumo:
This work aims to predict the total maximum demand of a transformer that will be used in power systems to attend a Multiple Unit Consumption (MUC) in design. In 1987, COSERN noted that calculation of maximum total demand for a building should be different from that which defines the scaling of the input protection extension in order to not overestimate the power of the transformer. Since then there have been many changes, both in consumption habits of the population, as in electrical appliances, so that this work will endeavor to improve the estimation of peak demand. For the survey, data were collected for identification and electrical projects in different MUCs located in Natal. In some of them, measurements were made of demand for 7 consecutive days and adjusted for an integration interval of 30 minutes. The estimation of the maximum demand was made through mathematical models that calculate the desired response from a set of information previously known of MUCs. The models tested were simple linear regressions, multiple linear regressions and artificial neural networks. The various calculated results over the study were compared, and ultimately, the best answer found was put into comparison with the previously proposed model
Resumo:
Fuzzy intelligent systems are present in a variety of equipment ranging from household appliances to Fuzzy intelligent systems are present in a variety of equipment ranging from household appliances to small devices such as digital cameras and cell phones being used primarily for dealing with the uncertainties in the modeling of real systems. However, commercial implementations of Fuzzy systems are not general purpose and do not have portability to different hardware platforms. Thinking about these issues this work presents the implementation of an open source development environment that consists of a desktop system capable of generate Graphically a general purpose Fuzzy controller and export these parameters for an embedded system with a Fuzzy controller written in Java Platform Micro Edition To (J2ME), whose modular design makes it portable to any mobile device that supports J2ME. Thus, the proposed development platform is capable of generating all the parameters of a Fuzzy controller and export it in XML file, and the code responsible for the control logic that is embedded in the mobile device is able to read this file and start the controller. All the parameters of a Fuzzy controller are configurable using the desktop system, since the membership functions and rule base, even the universe of discourse of the linguistic terms of output variables. This system generates Fuzzy controllers for the interpolation model of Takagi-Sugeno. As the validation process and testing of the proposed solution the Fuzzy controller was embedded on the mobile device Sun SPOT ® and used to control a plant-level Quanser®, and to compare the Fuzzy controller generated by the system with other types of controllers was implemented and embedded in sun spot a PID controller to control the same level plant of Quanser®
Resumo:
A agregação plaquetária avalia a função das plaquetas através de diferentes vias de ativação plaquetária in vitro, fornecendo traçados de ondas equivalentes à propriedade física dessa agregação. Sabendo-se que a aspirina acetila irreversivelmente a enzima cicloxigenase prevenindo a geração de tromboxana A2, potente ativador da agregação plaquetária, esta droga tem sido analisada há mais de trinta anos na clínica médica em pacientes com doenças cardiovasculares como uma potente droga antitrombótica. Foram nossos objetivos obter traçados de ondas correspondentes às fases da agregação plaquetária para nossa padronização utilizando nosso grupo controle de doadores de sangue e compará-las com nosso grupo estudo, frente a diferentes agentes agonistas em diferentes concentrações: ADP 1µM e 3µM; AA, 0,5mM; ADR, 0,05 mg/mL, 0,025 mg/mL e 0,010 mg/mL. Os grupos analisados foram constituídos por 41 cardíacos e 40 doadores de sangue considerados controle. Dos cardíacos, 33 faziam uso regular do AAS na concentração de 200 mg/dia e oito na concentração de 100 mg/dia, sendo todos considerados hipertensos. A padronização da agregometria estava na dependência do encontro de traçados correspondentes a ondas de agregação, sendo esses obtidos em porcentagem no tempo de cinco minutos estandartizados pelo aparelho utilizado. Comparando os resultados entre os pacientes e o grupo controle, foi possível observar que, na presença dos agentes agregantes ADP 1µM e ADP 3 µM, ADR 0,05 mg/mL, 0,025mg/mL e 0,010 mg/mL, os pacientes apresentaram 1ª onda, mas não 2ª onda. Por sua vez, no caso do AA 0,5 mM não houve o encontro de traçados de ondas.