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[EN] The study, monitoring and control of environmental phenomena such as the air pollution, climate control or homogenization temperature and humidity indoors, or understanding and extinguishing forest fires pose a constant challenge to the personnel responsible and especially to the researchers. Compete this problematic economic sectors where greenhouse crops, post-harvest cameras, chillers tractor ruminant farms, smart buildings, urban environmental studies, among many others used. In all of them there is a concern for consistency in production, for energy efficiency and environmental impact generated. It is for this homogenization, dispersion and stratification of climate variables and gases, closely related to the ventilation of outdoor spaces and venues of interest. For the understanding of physical phenomena that are generated and subsequent improvement in the structural design and automatic systems, we need a modeling and energy analysis, there are currently several methods: tracer gas techniques, intensive data collection accompanied with box-empirical modeling Black and resolution simulation of physical laws that govern the behavior of study spaces. Previous techniques independently are insufficient to provide practical solutions and are costly or highly particularized to the case study. That is why the technique Fluid Dynamics Computer (CFD), as a tool that is used to numerically solve the equations of continuity and momentum that govern energy exchange system in order to obtain the fields of speed and direction airflow, the distribution of temperature, humidity and specific gases, becomes viable for later models were used with advanced control systems. However, the CFD technique requires a validation of the results with intensive shooting (space-time) data. Most published studies refer in their conclusions to the need for such validation of the data produced and how it is done. This document, by means of case studies, seeks to address the complexity of some environmental phenomena using models with the technique of CFD, whose validation also requires a protocol systematically executed a System Data Acquisition (DAS) spatially distributed and temporally controlled, which is achieved with the design and installation of a Wireless Sensor Network (WSN). Then it finds a first justification case where having the need to study the homogenization of the microclimate of a greenhouse, a DAS is created through the integration of different technologies wired. It shows in addition to extensive technical development, an urgent need to move to a non-wired technology to achieve the spatial coverage required in rooms or spaces with greater volume. It is followed by a case study in the laboratory, which seeks to understand the distribution and stratification of a gas in a chamber with controlled ventilation. Using a CFD model, which in turn feeds and validated with a database generated from a gas sensor WSN becomes. Then, a case study where space analysis moves to a real environment and highly complex, as it is a street in the city of Valencia, Spain. / [ES] El estudio, monitoreo y control de fenómenos ambientales como lo es la contaminación atmosférica, el control del clima o la homogenización de la temperatura y la humedad en recintos cerrados, o el entendimiento y extinción de incendios forestales, plantean un reto constante a el personal responsable y especialmente a los investigadores. Compete esta problemática a sectores económicos donde se utilice cultivos bajo invernadero, cámaras de pos-cosecha, cámaras de refrigeración de tractores, explotaciones de rumiantes, edificaciones inteligentes, estudios ambientales urbanos, entre muchos otros. En todas ellas existe una preocupación por la uniformidad en la producción, por una eficiencia energética y por el impacto ambiental que se genera. Se encuentra pues dicha homogenización, dispersión y estratificación de las variables climáticas y de los gases, íntimamente relacionada con la ventilación de los espacios exteriores y los recintos de interés. Para la comprensión de los fenómenos físicos que se generan y posterior mejora del diseño estructural y de los sistemas automáticos, es necesario un modelado y estudio energético, existiendo actualmente varias metodologías: Técnicas con gas trazador, toma intensiva de datos acompañada con modelado empírico tipo caja negra, y simulación por resolución de las leyes físicas que gobiernan el comportamiento de los espacios de estudio. Las anteriores técnicas de forma independiente resultan insuficientes para dar soluciones prácticas, y resultan costosas o altamente particularizadas al caso de estudio. Es por ello que la técnica de Dinámica de Fluidos Computacionales (CFD), como herramienta que se emplea para resolver numéricamente las ecuaciones de continuidad y de momento que rigen los intercambios energéticos de un sistema con el fin de obtener los campos de velocidad y de dirección del flujo de aire, la distribución de la temperatura, de la humedad y de gases específicos, se hace viable para obtener los modelos que posteriormente se utilizaran con sistemas de control avanzado. Sin embargo, la técnica CFD requiere de una validación de los resultados con una toma (espacio-tiempo) intensiva de datos. La mayoría de los trabajos publicados hacen referencia en sus conclusiones a la necesidad de dicha validación de los datos arrojados y la forma en la que se hace. El presente documento, por medio de unos casos de estudio, busca abordar la complejidad de algunos fenómenos ambientales haciendo uso de modelos con dicha técnica de CFD, cuya validación exige además de un protocolo sistemáticamente ejecutado, un Sistema de Adquisición de Datos (DAS) espacialmente distribuido y temporalmente controlado, lo cual se alcanza con el diseño e instalación de una Red Inalámbrica de Sensores (WSN). Se encuentra entonces un primer caso justificativo, donde teniendo la necesidad del estudio de la homogenización del microclima de un invernadero, se genera un DAS gracias a la integración de diferentes tecnologías cableadas. Demuestra además de un extenso desarrollo técnico, una imperiosa necesidad de pasar a una tecnología no cableada para lograr la cobertura espacial requerida en recintos o espacios con mayor volumen. Le sigue un caso de estudio a nivel de laboratorio, donde se busca entender la distribución y estratificación de un gas en un recinto con ventilación controlada. Se hace uso de un modelo con CFD, que a su vez se alimenta y valida con un banco de datos generado gracias a una WSN con sensores de gases. Luego, un caso de estudio donde el espacio de análisis se traslada a un ambiente real y con alta complejidad, como lo es una calle de la ciudad de Valencia, España. / [CA] L'estudi, monitoratge i control de fenòmens ambientals com és la contaminació atmosfèrica, el control del clima o l'homogeneïtzació de la temperatura i la humitat en recintes tancats, o l'enteniment i extinció d'incendis forestals, plantegen un repte constant al personal responsable i especialment als investigadors. Competeix aquesta problemàtica a sectors econòmics on s'utilitza cultius sota hivernacle, càmeres de pos-collita, cambres de refrigeració de tractors, explotacions de remugants, edificacions intel ligents, estudis ambientals urbans, entre molts altres. En totes elles hi ha una preocupació per la uniformitat en la producció, per una eficiència energètica i per l'impacte ambiental que es genera. Es troba doncs aquesta homogeneïtzació, dispersió i estratificació de les variables climàtiques i dels gasos, íntimament relacionada amb la ventilació dels espais exteriors i els recintes d'interès. Per a la comprensió dels fenòmens físics que es generen i posterior millora del disseny estructural i dels sistemes automàtics, cal un modelatge i estudi energètic, existint actualment diverses metodologies: Tècniques amb gas traçador, presa intensiva de dades acompanyada amb modelatge empíric tipus caixa negra, i simulació per resolució de les lleis físiques que governen el comportament dels espais d'estudi. Les anteriors tècniques de forma independent resulten insuficients per donar solucions pràctiques, i resulten costoses o altament particularitzades al cas d'estudi. És per això que la tècnica de dinàmica de fluids Computacionals (CFD), com a eina que s'uilitilza per resoldre numèricament les equacions de continuïtat i de moment que regeixen els intercanvis energètics d'un sistema per tal d'obtindre els camps de velocitat i de direcció del flux d'aire, la distribució de la temperatura, de la humitat i de gasos específics, es fa viable per obtindre els models que posteriorment s'utilitzaran amb sistemes de control avançat. No obstant això, la tècnica CFD requereix d'una validació dels resultats amb una presa (espai-temps) intensiva de dades. La majoria dels treballs publicats fan referència en les seves conclusions a la necessitat d'aquesta validació de les dades llançats i la forma en què es fa. El present document, per mitjà d'uns casos d'estudi, busca abordar la complexitat d'alguns fenòmens ambientals fent ús de models amb aquesta tècnica de CFD, la validació exigeix a més d'un protocol sistemàticament executat, un Sistema d'Adquisició de Dades (DAS) espacialment distribuït i temporalment controlat, la qual cosa s'aconsegueix amb el disseny i instal lació d'una Xarxa Sense fil de Sensors (WSN). Es troba llavors un primer cas justificatiu, on tenint la necessitat de l'estudi de l'homogeneïtzació del microclima d'un hivernacle, es genera un DAS gràcies a la integració de diferents tecnologies cablejades. Demostra a més d'un extens desenvolupament tècnic, una imperiosa necessitat de passar a una tecnologia no cablejada per aconseguir la cobertura espacial requerida en recintes o espais amb més volum. El segueix un cas d'estudi a nivell de laboratori, on es busca entendre la distribució i estratificació d'un gas en un recinte amb ventilació controlada. Es fa ús d'un model amb CFD, que al seu torn s'alimenta i valida amb un banc de dades generat gràcies a una WSN amb sensors de gasos. Després, un cas d'estudi on l'espai d'anàlisi es trasllada a un ambient real i amb alta complexitat, com ho és un carrer de la ciutat de València, Espanya. / Marulanda Tobón, A. (2016). MODELOS EN DINÁMICA DE FLUIDOS COMPUTACIONAL PARA APLICACIONES AMBIENTALES Y SU VALIDACIÓN CON SISTEMAS DE ADQUISICIÓN DE DATOS BASADOS EN REDES DE SENSORES INALÁMBRICAS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63461

Functional and cost effective systems for the full electrification of a bus network are areas of intense research and development. The electrification can be accomplished using different technological solutions, for example using opportunity charging or using an electric road system – ERS. Both opportunity charging and ERS have the potential to be integrated into already existing bus lines. With opportunity charging, the regular dwell time at the end stops is used for the bus to recharge its batteries and with an ERS the bus can charge dynamically along the road. The purpose of this report is to analyze how the existing Alfa- and Beta line at Stockholm Arlanda Airport, in a functional and cost effective way, can be electrified using either opportunity charging or an ERS. The tradeoff between required charging power, battery capacity and the necessity to change the existing running schedule is explained in detail. In addition, the impact on the electrical grid is analyzed based on different load profiles of different charging stations using different power levels. The analysis is based on real data from the Alfa – and Beta line with its existing buses, the electrical grid at Arlanda and data provided by both the leading (electrical) bus manufacturers and the leading charging infrastructure manufacturers.  The outcome of this report suggests that a full electrification of the existing Alfa- and Beta line has the potential to lower CO2-emissions and energy use at a functional and cost effective way.

My dissertation address is to describe the long distance bus (LDB) transport, its structure, service adequacy and the role it plays in linking the core to the periphery of Ethiopia. The study applied both qualitative and quantitative data analyses. The quantitative data was mainly collected by using questionnaires, from the selected passengers and operators by longitudinal survey, 384 passengers, or 10 %, from each bus took part in the survey. Of these, only 241 questionnaires (63%) were fully completed and used for this analysis. And 6 % of buses or operators (64) were selected by systematic sampling. The routes and towns were also selected by lottery method. The qualitative data was mainly collected by interview. Among these, 5 % (twenty-five) of experts from the City Transport Bureau; the heads of LDB Associations; the owners of LDB; the Federal Transport bureau; and the Mercato Bus terminal. An interview was analyzed based on their own explanations. FGDs were carried out with passengers awaiting departure in the terminal (off-journey). The secondary sources were taken from both the EFTA and Mercato bus terminal dispatch report. The analysis was made mostly by integrating method, and in some cases with separate analysis. Beside with other inferential statistical, Pearson correlation was also applied. The growth rate for level one and level two buses had risen more than 100 % per annum, whereas level three buses showed a decline of 18 % per year. The whole sector shows a 6.6 % growth rate, which is double that of the population growth (2.6 %). The rate of bus dispatch is very high, approximately 38 per day, on the Dessie and Mojo route. The average bus dispatch in all directions is about 32. In terms of service provision and area coverage, level one buses interlink about 23 major towns. Level two buses service more than 70 major towns, and level three more than 110. The highest record of both area and service coverage was occupied by first level buses servicing Dessie, Mekele, Shashemene, Hawassa, and Jimma. On average, the majority of towns are being serviced by one bus, irrespective of their levels. The area and service coverage is thus very high for level three buses, compared with levels two and one. The Dessie and Mojo lines enjoy the highest bus coverage. LDBs typically provide transport for distances of less than 400 kilometres. They contribute towards core to peripheral ties of the nation. This result is expressed by Krugman’s (1991) core-periphery theory. The service adequacy of the industry indicates that above half of the operators would have to wait approximately one hour to pick up passengers and 1 or 2 days per week to get the turn too. This reveals that Levels one, two and three operators are dormant for 1 or 2 days per week. Supply is thus greater than demand, causing the emergence of an informal LDB service. The fact that about 60 % of passengers have to wait for approximately an hour to catch a bus, after collecting tickets, indicates the demand. The buses’ downtimes in order to secure a full load on each departure are positively correlated with bus levels. The LDB provide more for mobility of goods and peoples that can be shape land use and development patterns, and it generate jobs. This enable more for economic growth. Thus, level one is more attractive than other levels. The study identifies the major challenges facing LDB transport. Integration within stakeholders, both internally and externally, is crucial to satisfy the passenger. / Geography / D. Phil. (Geography)

Made available in DSpace on 2014-12-17T14:54:54Z (GMT). No. of bitstreams: 1 ClovisBMO_TESE_1_a_75.pdf: 2549651 bytes, checksum: d03d835bba88763c08a8cb99eac15cd8 (MD5) Previous issue date: 2010-03-12 / Universidade Federal do Rio Grande do Norte / This study presents a description of the development model of a representation of simplified grid applied in hybrid load flow for calculation of the voltage variations in a steady-state caused by the wind farm on power system. Also, it proposes an optimal load-flow able to control power factor on connection bar and to minimize the loss. The analysis process on system, led by the wind producer, it has as base given technician supplied by the grid. So, the propose model to the simplification of the grid that allows the necessity of some knowledge only about the data referring the internal network, that is, the part of the network that interests in the analysis. In this way, it is intended to supply forms for the auxiliary in the systematization of the relations between the sector agents. The model for simplified network proposed identifies the internal network, external network and the buses of boulders from a study of vulnerability of the network, attributing them floating liquid powers attributing slack models. It was opted to apply the presented model in Newton-Raphson and a hybrid load flow, composed by The Gauss-Seidel method Zbarra and Summation Power. Finally, presents the results obtained to a developed computational environment of SCILAB and FORTRAN, with their respective analysis and conclusion, comparing them with the ANAREDE / Este trabalho apresenta uma descri??o do desenvolvimento de modelo para representa??o de rede simplificada aplicado em fluxo de carga h?brido para c?lculo das varia??es de tens?o em regime permanente provocadas pela conex?o de aerogeradores na rede el?trica. Al?m disso, se apresenta um fluxo de carga ?timo capaz de controlar remotamente o fator de pot?ncia na barra de conex?o e minimizar perdas. O princ?pio do processo de an?lise do sistema, conduzido pelo acessante, tem como base dados t?cnicos fornecidos pela rede acessada. Assim, se prop?e um modelo para simplifica??o de redes que permita a necessidade do conhecimento apenas dos dados referente a rede interna, ou seja, a parcela da rede de interesse para an?lise. Dessa forma, pretende-se fornecer meios para auxiliar na sistematiza??o das rela??es entre concession?ria e acessante. O modelo para simplifica??o de rede proposto identifica a rede interna, rede externa e as barras de fronteira a partir de dados provenientes de um estudo de vulnerabilidade da rede, atribuindo-as pot?ncias l?quidas flutuantes, ou seja, modelando-as como barras slack. Aplica-se o referido modelo no fluxo de carga Newton-Raphson e em um fluxo de carga h?brido, composto pelos m?todos de Gauss Seidel Zbarra e Soma de Pot?ncias. Ao final, apresentam-se os resultados obtidos por um ambiente computacional desenvolvido do SCILAB e FORTRAN, com suas respectivas an?lises e conclus?es, comparando-os com o ANAREDE

MURP / Department of Urban and Regional Planning / This study focuses on the evaluation of intelligent transport systems making use of the BRT-Rea-vaya in Johannesburg as a case study. This study was motivated by the observation that few studies have been conducted in the study area that tackle explicitly intelligent transport systems evaluation. Intelligent transport systems can assist in improving private and public transportation systems and operations performance. In the public sector where various modes of transport such as the taxi, metro bus, metro rail, Gautrain and the BRT Rea-vaya operates, intelligent transport systems present opportunities for improving Level of Service (LOS) delivery. In Johannesburg, the BRT Rea vaya system was adopted by the Johannesburg metropolitan municipality to provide a safe, reliable, efficient and accessible public transport system. The BRT Rea vaya system is aimed at providing a better public transport, operating systems and service. For the BRT Rea vaya systems to achieve its primary goals and objectives, an intelligent transport system was incorporated to better manage the BRT Rea-vaya systems operations and activities. The study disclosed the status quo, opinions and attitudes of commuters regarding their experiences with the BRT Rea vaya public transport systems in Johannesburg. Furthermore, the study investigated whether the original objectives and aims of intelligent transport system in the BRT Rea-vaya have been meet. A central theme of the investigation is seeking to understand constraints and opportunities regarding BRT Rea-vaya intelligent transport systems‘ operations and activities in Johannesburg. The use of primary and secondary data such as questionnaires, key informant interviews, observation, journals and previous researches related to intelligent transport systems were used to acquire an in-depth understanding of the operational management of BRT Rea-vaya intelligent transport system. Collected data was analyzed using Statistical Package for Social Sciences (SPSS) with the aid of Microsoft Excel making use of descriptive statistics, regression analysis, cross tabulation and chi-square test. This was presented using tables, graphs, maps etc. Qualitative data was analyzed making use of a thematic approach. The study resonates in the need for rapid public transport systems to provide lessons for improving and adopting intelligent transport systems. As an end product, the research provided a framework of analysis on how to integrate intelligent transport systems in the context of Bus rapid transit systems.

Controlling the balance of production and consumption of electricity will become increasingly challenging as the transport sector gradually converts to electric vehicles along with a growing share of wind power in the Swedish electric power system. This puts greater demand on resources that maintain the balance to ensure stable grid operation. The balancing act is called frequency regulation which historically has been performed almost entirely by hydropower. As the power production becomes more intermittent with renewable energy sources, frequency regulation will need to be performed in higher volumes on the demand side by having a more flexible consumption. In this report, the electrification of 17 buses Svealandstrafiken bus depot in Västerås has been studied. The aim has been to assess different charging strategies to efficiently utilize the available time and power but also to investigate if Svealandstrafiken can participate in frequency regulation. A smart charging model was created that demonstrated how smart charging can be implemented to optimize the charging in four different cases. The simulated cases were: charging with load balancing, reduced charging power, frequency regulation, and electrifying more buses. The results show that the power capacity limit will be exceeded if the buses are being charged directly as they arrive at the depot and without scheduling the charging session. By implementing smart charging, Svealandstrafiken can fully charge the 17 buses within the power capacity limit of the depot with 82 minutes to spare. By utilizing this 82-minute margin in the four different charging strategies, it was found that Svealandstrafiken can save 88 200SEK per year by load balancing, save 30 000 SEK per year by reducing the charging power by 10 %, earn 111 900 SEK per year by frequency regulation or electrify five more buses. Reducing the charging power may also increase the lifetime of the batteries but quantifying this needs further studies. Conclusively, there is economic potential for Svealandstrafiken for implementing smart charging.

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MENEZES, Patricia. Fortaleza de ônibus: quebra-quebra, lock-out e liberação na construção do serviço de transporte coletivo de passageiros entre 1945 e 1960. 2009. 244 f. Dissertação (Mestrado em História) - Universidade Federal do Ceará, Departamento de História, Programa de Pós-Graduação em História Social, Fortaleza-CE, 2009. / Submitted by Raul Oliveira (raulcmo@hotmail.com) on 2012-06-28T14:26:44Z No. of bitstreams: 1 2009_Dis_PMenezes.pdf: 9548339 bytes, checksum: 29a145cd86f43d79dedae117b5941238 (MD5) / Approved for entry into archive by Maria Josineide Góis(josineide@ufc.br) on 2012-07-05T14:06:48Z (GMT) No. of bitstreams: 1 2009_Dis_PMenezes.pdf: 9548339 bytes, checksum: 29a145cd86f43d79dedae117b5941238 (MD5) / Made available in DSpace on 2012-07-05T14:06:48Z (GMT). No. of bitstreams: 1 2009_Dis_PMenezes.pdf: 9548339 bytes, checksum: 29a145cd86f43d79dedae117b5941238 (MD5) Previous issue date: 2009 / This paper aims to rebuild the process of consolidation of public transportation system with buses in Fortaleza, from 1945 to 1960. It focus on the years after trolley cars stopped to circulate in Fortaleza, in the late days of 1947, highlighting the transformations in the city and the conditions of public mobility in the 1950’s. On a time of city growth and diversification of urban experiences, it shows the first days of social groups related to public transportation, with their methods in the struggle that happened with the attempts to normalize the service offered to the population of the city. / Este trabalho pretende reconstruir o processo de formação do sistema de transporte coletivo de passageiros realizado por ônibus em Fortaleza entre 1945 a 1960. O estudo compreende os anos posteriores à retirada de circulação dos bondes elétricos da Ceará Light, no final do ano de 1947, assinalando as transformações da cidade e as condições da mobilidade pública no decorrer dos anos de 1950. Num universo de ampliação de territórios e de diversificação das experiências urbanas, a narrativa percorre a constituição recíproca dos grupos sociais ligados ao transporte, percorrendo seus discursos e suas práticas políticas nos conflitos que envolveram as tentativas de normalização do serviço.