845 resultados para guyed tower


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In this article I analyze the relationships between space and the main characters in La Tour d’amour, by Rachilde. More specifically I focus on how space has already stunned one of the character’s speech and communicative abilities and it is now in the process of impairing speech in the other. By analyzing the novelist’s use of myths, references to the divinity and, especially, the many instances that offer evidence of widespread corruption in the characters’ language, I show how the lighthouse in which the characters dwell can be interpreted as a decadent Tower of Babel.

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A EGEO Solventes S.A. é uma empresa com atividade na área da gestão de resíduos, focando-se na regeneração de solventes. Na unidade industrial da empresa recorre-se à destilação de misturas de solventes usados para obtenção do solvente regenerado. Esta operação exige água para o arrefecimento e condensação dos destilados das misturas de solventes, que, posteriormente, é arrefecida em torres de refrigeração instaladas na unidade. Durante o tempo de operação da unidade foram identificados problemas na condensação dos solventes limpos, obrigando a que se ligassem dois condensadores em série para assegurar a condensação do vapor produzido na destilação e à necessidade de caudais maiores de utilidade fria. Outro dos problemas identificados foi a baixa eficiência das torres de refrigeração, uma vez que a diferença de temperaturas da água à entrada e à saída do equipamento é muito baixa. Assim sendo, o objetivo principal deste trabalho é identificar as principais causas para a baixa eficiência dos equipamentos e propor alterações aos equipamentos ou soluções de melhoria do processo. Para diagnosticar estes problemas foram recolhidas amostras para determinação da composição do solvente limpo obtido e registadas as condições de operação para obtenção da mistura ECOSOLVE MET. Recorrendo a metodologias de projeto determinou-se o fator de resistência do fouling no condensador C1 e seguidamente a geometria, a alocação de correntes e a orientação do condensador mais adequadas e concluiu-se que este está sujeito a uma forte acumulação de material nas paredes e que a melhor opção seria recorrer a um permutador horizontal com condensação na carcaça, mas aumentando o número de passagens da água nos tubos. No que diz respeito à operação da torre de arrefecimento, determinou-se o caudal mínimo de ar para determinadas condições de operação e verificou-se que o caudal de ar alimentado à torre era superior ao mínimo determinado. Foram observadas diferenças quando comparadas as condições de operação experimentais com a performance da unidade usando oito enchimentos estruturados e aleatórios para os quais há dados na literatura São também apresentadas alternativas de operação e o projeto de uma torre de arrefecimento de água, sustentada numa análise económica de todo o processo. As simulações foram realizadas com recurso ao AspenPlus®.

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The Parabolic Trough (PT) is the most used concentrator in CSP (Concentrated Solar Power). However, this concentrator technology is facing a significant challenge to increase its overall efficiency and cost-effectiveness. Meanwhile, other low-cost solutions such as Fresnel concentrators are also being perceived as potentially attractive. In order to achieve the lower cost goal, new optical solutions can be considered, in parallel with improvements coming, for instance, through the use of new materials or manufacturing solutions. But conventional PTs can still be improved to yield, for instance, higher concentration values, a possible starting point for higher conversion efficiency. These new solutions, in turn, can also be useful for other technologies and applications (Fresnel Concentrators, Central Tower Receivers, etc.). However it is easier to develop and test these solutions in conjunction with parabolic primaries (continuum primary). And that is the topic of this paper: to present a new Compound Elliptical-type Concentrator for a parabolic primary with a tubular receiver. A comparison is made between this new concentrator and two other concentrators (a conventional PT concentrator and a XX SMS (Simultaneous Multiple Surface) concentrator), as well as a calculation of the total amount of collected energy (kW h) for a particular location, Faro (Portugal). The paper ends with a discussion of the results obtained, their impact and possible applications in the future.

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This dissertation seeks to discern the impact of social housing on public health in the cities of Glasgow, Scotland and Baltimore, Maryland in the twentieth century. Additionally, this dissertation seeks to compare the impact of social housing policy implementation in both cities, to determine the efficacy of social housing as a tool of public health betterment. This is accomplished through the exposition and evaluation of the housing and health trends of both cities over the course of the latter half of the twentieth century. Both the cities of Glasgow and Baltimore had long struggled with both overcrowded slum districts and relatively unhealthy populations. Early commentators had noticed the connection between insanitary housing and poor health, and sought a solution to both of these problems. Beginning in the 1940s, housing reform advocates (self-dubbed ‘housers') pressed for the development of social housing, or municipally-controlled housing for low-income persons, to alleviate the problems of overcrowded slum dwellings in both cities. The impetus for social housing was twofold: to provide affordable housing to low-income persons and to provide housing that would facilitate healthy lives for tenants. Whether social housing achieved these goals is the crux of this dissertation. In the immediate years following the Second World War, social housing was built en masse in both cities. Social housing provided a reprieve from slum housing for both working-class Glaswegians and Baltimoreans. In Baltimore specifically, social housing provided accommodation for the city’s Black residents, who found it difficult to occupy housing in White neighbourhoods. As the years progressed, social housing developments in both cities faced unexpected problems. In Glasgow, stable tenant flight (including both middle class and skilled artisan workers)+ resulted in a concentration of poverty in the city’s housing schemes, and in Baltimore, a flight of White tenants of all income levels created a new kind of state subsidized segregated housing stock. The implementation of high-rise tower blocks in both cities, once heralded as a symbol of housing modernity, also faced increased scrutiny in the 1960s and 1970s. During the period of 1940-1980, before policy makers in the United States began to eschew social housing for subsidized private housing vouchers and community based housing associations had truly taken off in Britain, public health professionals conducted academic studies of the impact of social housing tenancy on health. Their findings provide the evidence used to assess the second objective of social housing provision, as outlined above. Put simply, while social housing units were undoubtedly better equipped than slum dwellings in both cities, the public health investigations into the impact of rehousing slum dwellers into social housing revealed that social housing was not a panacea for each city’s social and public health problems.

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In this study, thermal, exergetic analysis and performance evaluation of seawater and fresh wet cooling tower and the effect of parameters on its performance is investigated. With using of energy and mass balance equations, experimental results, a mathematical model and EES code developed. Due to lack of fresh water, seawater cooling is interesting choice for future of cooling, so the effect of seawater in the range of 1gr/kg to 60gr/kg for salinity on the performance characteristics like air efficiency, water efficiency, output water temperature of cooling tower, flow of the exergy, and the exergy efficiency with comparison with fresh water examined. Decreasing of air efficiency about 3%, increasing of water efficiency about 1.5% are some of these effects. Moreover with formation of fouling the performance of cooling tower decreased about 15% which this phenomena and its effects like increase in output water temperature and tower excess volume has been showed and also accommodate with others work. Also optimization for minimizing cost, maximizing air efficiency, and minimizing exergy destruction has been done, results showed that optimization on minimizing the exergy destruction has been satisfy both minimization of the cost and the maximization of the air efficiency, although it will not necessarily permanent for all inputs and optimizations. Validation of this work is done by comparing computational results and experimental data which showed that the model have a good accuracy.

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Mirocaris fortunata were sampled from the Lucky Strike hydrothermal vent area (Eiffel Tower site) on the mid-Atlantic ridge during the French DIVA 2 cruise (June 1994). Small adults (17 to 22 mm total length), although morphologically identical, could be divided into 2 categories on the basis of pigmentation, lipid composition and C-13/C-12 stable isotope ratios of fatty acids. Highly pigmented small adults (8.6 to 9.2 mu g carotenoid shrimp(-1)) contained higher levels of total lipid than similar-sized individuals containing lower levels of pigment (0.9 to 2.9 mu g carotenoid shrimp(-1)). Lipid class analysis indicated that wax esters comprised 62.5% of total lipid in the former group. These pigmented shrimp also contained high proportions of polyunsaturated fatty acids (PUFA), particularly the phototrophic microplanktonic markers 20:5(n-3) and 22:6(n-3) (14.0 and 33.5% respectively). By contrast small adults (22 mm) and adult shrimp (25 to 26 mm) with low levels of carotenoid pigmentation contained lower amounts of total lipid, little or no wax ester and low levels of 20:5(n-3) and 22:6(n-3), but did contain 16:2(n-4) and 18:2(n-4) and the non-methylene interrupted dienes 20:2 Delta 5,13 and 22:2 Delta 7,15. GC-IRMS analysis of all fatty acids and fatty alcohols in the pigmented small adults indicated delta(13)C values of -18.2 to -27.7 parts per thousand, which is consistent with a photosynthetic carbon source for these compounds. The C-13/C-12 isotope composition of fatty acids from low-pigmented small adults and adults was more variable (-12.5 to -33.1 parts per thousand) and suggests a bimodal distribution which may be attributable to differing nutritional sources or the physiological/reproductive status of these shrimp. Samples of eggs, which are carried by the female on the pleopods, represented approximately 57% of total somatic lipid which indicates a substantial reproductive investment by this species. The egg lipids comprised high proportions of triacylglycerols (64.4 to 78.0% of total lipid) whilst the fatty acid composition was dominated by the monounsaturated fatty acids 16:1(n-7), 18:1(n-7) and 18:1(n-9), which accounted for 65.7 to 33.5% of total fatty acids. By contrast, PUFA were relatively minor components of egg lipids, particularly 20:5(n-3) and 22:6(n-3), which accounted for only 1.1 and 2.9% of total egg fatty acids respectively. This indicates that the reproductive investment by this species is supported mainly by material derived from bacterial chemosynthesis. The potential for M. fortunata hedge betting by producing larvae which either metamorphose at the vent site or adopt a bathypelagic lifestyle and delay metamorphosis to facilitate more widespread dispersal is discussed.

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Los hidrocarburos pesados son el mayor recurso del petróleo en el mundo, sin embargo en el pasado se habían dejado de lado como recurso energético debido a las dificultades y costos asociados de su producción [1]. La industria financia estas investigaciones por la importancia del tema en producción y caracterización. Al trabajar con una torre de vacio los datos necesarios para los cálculos son las temperaturas ASTM (10mmHg) y la densidad del crudo con la cual se obtiene la curva TBP760 (True Boiling Point), también se necesita las especificaciones de los productos y los rendimientos respecto de la alimentación. Para poder correlacionar los distintos puntos de ebullición con los porcentajes de vaporizado para cada cambio de presión de los distintos productos, se construye un diagrama de fases con las temperaturas EFV760 (Equilibrium Flash Vaporization) y EFV10. El simulador a través de cálculos internos resuelve automáticamente el diagrama de fases, en comparación con la dificultad que representan los cálculos manuales del mismo, tal como son explicitados precedentemente. En este trabajo se desarrolla la simulación de una torre de vacío mediante el simulador Aspen HYSYS V8.3, empleando como alimentación un crudo pesado. Lo antes expuesto constituye una importante ventaja el uso del simulador frente al cálculo convencional, considerando los tiempos de resolución de los diseños de procesos.

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Objetivo: Investigar o efeito de dois programas de reabilitação psicomotora (atividade contínua versus atividade intervalada) na capacidade neuromotora de idosos institucionalizados. Metodologia: A amostra integrou 17 participantes (85,81±6,26 anos) que, numa fase inicial, mantiveram as atividades durante 6 semanas (período de controlo) e, posteriormente, 9 integraram um programa com intervenção intervalada (GI) e 8 um programa com intervenção contínua (GC). Ambos os programas tiveram a duração de 12 semanas, com uma periodicidade de 2 sessões por semana e duração de 60 minutos. Foram avaliadas as variáveis atenção (Trail Making Test), capacidade de planeamento (Torre de Londres), o desempenho em situação de dupla tarefa (Timed Up and Go modificado) e equilíbrio (Timed Up and Go e Índice de Tinetti). Resultados: O GI evidenciou melhorias significativas nas variáveis da atenção, da capacidade de planeamento, dupla tarefa e equilíbrio (p<0,05), enquanto que o GC apenas o evidenciou na variável capacidade de planeamento (p<0,05). Conclusão: Os resultados sugerem que o programa de reabilitação psicomotora com atividade intervalada será mais benéfico para os idosos institucionalizados que programa com atividade contínua, particularmente na atenção, no desempenho em situação de dupla tarefa e no equilíbrio; ABSTRACT: Objective: To research the effect of two psychomotor rehabilitation programs (continuous activity against intervealed activity) in the neuromotor ability of institutionalized elderly people. Metodology: The sample had 17 participants (85.81 ± 6.26 years), that in an initial phase retained activity for 6 weeks (control period) and then, 9 integrated a program with intervealed intervention (GI) and 8 a program with continuous intervention (GC). ). Both of the programs had 12 weeks, 2 sessions per week and 60 minutes per session. Was evaluated the variables attention (Trail Making Test); planning capacity (London Tower); dual task capacity (modified Timed Up and Go) and balance (Timed Up and Go and Tinetti Index). Results: The GI showed significant improvements in the variables attention, performance in dual task ability and balance (p<0,05), while GC revealed significant improvements in planning capacity (p<0,05). Conclusion: The results suggest that the psychomotor rehabilitation program with intervealed activity will be more beneficial for the institutionalized elderly than the program with continuous activity, particularly in the attention, planning capacity, performance in dual task ability and balance.

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Estudou-se a Camada Limite Noturna ? CLN sobre área de floresta tropical primária a nordeste do Estado do Amazonas, no Observatório Amazônico da Torre Alta ? OATA ou Amazon Tall Tower Observatory ? ATTO. Foi aplicada a metodologia disponível na literatura que permitiu a caracterização da CLN em três regimes turbulentos: 1º) de turbulência fraca, com velocidade média do vento baixa; 2º) de turbulência forte, com velocidade do vento alta e, 3º) turbulência intermitente e condições de não estacionariedade. Existem variações sazonais nos valores de ?c? e ao passar de um regime para outro. Foram investigadas algumas das principais características estatísticas das concentrações de CO2 ? ?c? de cada um dos regimes turbulentos. ?c? aumenta levemente com a elevação do valor de uma escala característica de velocidade turbulenta, VTKE, até um valor limiar, VL, a partir do qual tem-se um aumento súbito nos valores de ?c?. Esses resultados têm importantes consequências para a parametrização de grandezas meteorológicas na CLN e modelagem do escoamento atmosférico na interface floresta-atmosfera.

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In this study, was used a very promising technique called of pyrolysis, which can be used for obtaining products with higher added value. From oils and residues, since the contribution of heavier oils and residues has intensified to the world refining industry, due to the growing demand for fuel, for example, liquid hydrocarbons in the range of gasoline and diesel. The catalytic pyrolysis of vacuum residues was performed with the use of a mesoporous material belonging the M41S family, which was discovered in the early 90s by researchers Mobil Oil Corporation, allowing new perspectives in the field of catalysis. One of the most important members of this family is the MCM-41, which has a hexagonal arrangement of mesopores with pore diameters between 2 and 10 nm and a high specific surface area, making it very promising for use as a catalyst in petroleum refining for catalytic cracking, and their mesopores facilitate the access of large hydrocarbon molecules. The addition of aluminum in the structure of MCM-41 increases the acidity of the material, making it more positive for application in the petrochemical industry. The mesoporous material of the type Al-MCM41 (ratio Si / Al = 50) was synthesized by hydrothermal method starting from the silica gel, NaOH and distilled water added to the gel pseudobohemita synthesis. Driver was used as structural CTMABr. Removal of organic driver (CTMABr) was observed by TG / DTG and FTIR, but this material was characterized by XRD, which was observed the formation of the main peaks characteristic of mesoporous materials. The analysis of adsorption / desorption of nitrogen this material textural parameters were determined. The vacuum residues (VR's) that are products of the bottom of the vacuum distillation tower used in this study are different from oil fields (regions of Ceará and Rio de Janeiro). Previously characterized by various techniques such as FTIR, viscosity, density, SARA, elemental analysis and thermogravimetry, which was performed by thermal and catalytic degradation of vacuum residues. The effect of AlMCM-41 was satisfactory, since promoted a decrease in certain ranges of temperature required in the process of conversion of hydrocarbons, but also promoted a decrease in energy required in the process. Thus enabling lower costs related to energy expenditure from degradation during processing of the waste

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This work aims to obtain a low-cost virtual sensor to estimate the quality of LPG. For the acquisition of data from a distillation tower, software HYSYS ® was used to simulate chemical processes. These data will be used for training and validation of an Artificial Neural Network (ANN). This network will aim to estimate from available simulated variables such as temperature, pressure and discharge flow of a distillation tower, the mole fraction of pentane present in LPG. Thus, allowing a better control of product quality

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In my eight years as a professional journalist, I have been a front line observer of the extreme level of violence which occurs everyday in our society. As victims, consumers or perpetrators of violence, this phenomenon is now a part of our existence. As a reporter for the Spanish national newspaper El País I have been witness to the most terrible acts of violence. In Venezuela, with one of the highest rates of criminality in the world, I saw piles of bodies stacked up in mortuaries. In Argentina, I reported on the most brutal crimes including the rape of children by policemen. I believe that my interest in the manifestations and causes of violence was aroused during my time as a journalist. On a personal level, I was deeply affected by the twin poles of attraction/repulsion which the violent images produced in me. The first time I visited New York in 2003, I talked to various people who were selling photos of the victims of the Twin Tower attacks. They had laid out their wares along the wire fence that separated Ground Zero from the main public areas. One particular photograph made an indelible impression on my mind: a ghost like corpse covered in white dust which was streaked with blood. It is an image I will never forget. If I remember well, a complete album of these gruesome images cost about ten dollars. At the same time, I also became interested in islamic terrorism: its complexity and the great impact it has made on Western society. One only has to look at the front page of the press around the world to read about war, terrorism or the constant violation of human rights. The words Al-Qaeda, Daesh, Boko Haram and Islamic State have sadly become parts of our everyday language. The nihilistic philosophy which promisess eternal life in exchange for self-inmolation is a new, highly worrying reality, especially painful when it involves young people who become indoctrinated through the social media. They have become the most loyal supporters of a fanatical and uncompromising version of Islam. The stark reality is that these young recruits to Jihad (holy war) were born in places like London, Paris, Rome or Madrid...

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This paper is on a wind energy conversion system simulation of a transient analysis due to a blade pitch control malfunction. The aim of the transient analysis is the study of the behavior of a back-to-back multiple point clamped five-level full-power converter implemented in a wind energy conversion system equipped with a permanent magnet synchronous generator. An alternate current link connects the system to the grid. The drive train is modeled by a three-mass model in order to simulate the dynamic effect of the wind on the tower. The control strategy is based on fractional-order control. Unbalance voltages in the DC-link capacitors are lessen due to the control strategy, balancing the capacitor banks voltages by a selection of the output voltage vectors. Simulation studies are carried out to evaluate not only the system behavior, but also the quality of the energy injected into the electric grid.

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This paper is on modeling and simulation for an offshore wind system equipped with a semi-submersible floating platform, a wind turbine, a permanent magnet synchronous generator, a multiple point clamped four level or five level full-power converter, a submarine cable and a second order filter. The drive train is modeled by three mass model considering the resistant stiffness torque, structure and tower in deep water due to the moving surface elevation. The system control uses PWM by space vector modulation associated with sliding mode and proportional integral controllers. The electric energy is injected into the electric grid either by an alternated current link or by a direct current link. The model is intend to be a useful tool for unveil the behavior and performance of the offshore wind system, especially for the multiple point clamped full-power converter, under normal operation or under malfunctions.

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An integrated mathematical model for the simulation of an offshore wind system performance is presented in this paper. The mathematical model considers an offshore variable-speed turbine in deep water equipped with a permanent magnet synchronous generator using multiple point full-power clamped three-level converter, converting the energy of a variable frequency source in injected energy into the electric network with constant frequency, through a HVDC transmission submarine cable. The mathematical model for the drive train is a concentrate two mass model which incorporates the dynamic for the blades of the wind turbine, tower and generator due to the need to emulate the effects of the wind and the floating motion. Controller strategy considered is a proportional integral one. Also, pulse width modulation using space vector modulation supplemented with sliding mode is used for trigger the transistors of the converter. Finally, a case study is presented to access the system performance.