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Modelagem estruturada e sistemas inteligentes : uma aplicação a sistemas de transporte ferroviario

Magali Mercedes Rondon Gonzalez
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/09/2000 PT
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Modelos de linhas ferroviárias são essenciais para análise e decisão em sistemas ferroviários. Estes modelos fornecem meios para análise de movimento e despacho, fornecendo meios para simulação, análise de operações, otimização, controle de circulação e expansão de capacidade, entre outros problemas. Este trabalho apresenta um modelo estruturado de linha que estende o modelo clássico proposto por Petersen e Taylor em 1982. O modelo proposto acrescenta funcionalidades que não foram consideradas no modelo original e foi construído com uma visão que privilegia a orientação a objetos. Como conseqüência, um sistema computacional foi implementado em linguagem Java com o intuito de fornecer uma ferramenta de análise e suporte na tomada de decisão. Mais especificamente, o modelo aqui desenvolvido acrescenta as seguintes funcionalidades ao modelo original: criação de modelos de trens, percursos e escalas, circulação de trens numa malha ferroviária e perturbação de trens. A ferramenta computacional fornece mecanismos para caracterizar modelos de linha, simular a circulação de trens em uma malha ferroviária, visualizar dados e obter resultados de simulação que traduzem o desempenho do sistema ferroviário. Além disso...

Estrategias de decisão para o planejamento de circulação de trens em tempo real; Decision making strategies for real time trains movement planning

Alexandre Tazoniero
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/06/2007 PT
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36.45%
O transporte ferroviário tem grande participação no transporte de cargas e passageiros em todo o mundo. No Brasil a malha ferroviária sofreu um processo de abandono e deterioração no período de 1960 a 1990. A partir de 1990 a privatização da rede ferroviária nacional iniciou uma retomada de investimentos e nos últimos anos à demanda por transporte ferroviário vem crescendo significativamente. É necessário, então, que os recursos da ferrovia sejam utilizados de maneira eficiente para atender a crescente demanda, o que exige planejamento estratégico, táctico e operacional. No nível operacional uma das principais etapas e também umas das mais carentes de ferramentas computacionais é o Planejamento de Circulação de trens. O processo operacional de uma ferrovia é dinâmico, sujeito a inúmeras interferências imprevisíveis e uma ferramenta computacional para o apoio ao planejamento de circulação de trens deve fornecer soluções com tempo de processamento compatível com essa realidade. Este trabalho propõe algoritmos para o planejamento de circulação de trens em tempo real, utilizando metodologias de inteligência computacional e conjuntos nebulosos. Um algoritmo objetiva decidir localmente a preferência entre trens concorrendo pelo uso de um segmento de linha singela de modo a seguir uma referência de percurso fornecida por algum algoritmo de otimização ou por um especialista. Outro algoritmo decide...

Surveillance for West Nile, Dengue, and Chikungunya Virus Infections, Veneto Region, Italy, 2010

Gobbi, Federico; Barzon, Luisa; Capelli, Gioia; Angheben, Andrea; Pacenti, Monia; Napoletano, Giuseppina; Piovesan, Cinzia; Montarsi, Fabrizio; Martini, Simone; Rigoli, Roberto; Cattelan, Anna M.; Rinaldi, Roberto; Conforto, Mario; Russo, Francesca; Palù
Fonte: Centers for Disease Control and Prevention Publicador: Centers for Disease Control and Prevention
Tipo: Artigo de Revista Científica
Publicado em /04/2012 EN
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In 2010, in Veneto Region, Italy, surveillance of summer fevers was conducted to promptly identify autochthonous cases of West Nile fever and increase detection of imported dengue and chikungunya in travelers. Surveillance highlighted the need to modify case definitions, train physicians, and when a case is identified, implement vector control measures

Cholera Prevention Training Materials for Community Health Workers, Haiti, 2010–2011

Rajasingham, Anu; Bowen, Anna; O’Reilly, Ciara; Sholtes, Kari; Schilling, Katie; Hough, Catherine; Brunkard, Joan; Domercant, Jean Wysler; Lerebours, Gerald; Cadet, Jean; Quick, Robert; Person, Bobbie
Fonte: Centers for Disease Control and Prevention Publicador: Centers for Disease Control and Prevention
Tipo: Artigo de Revista Científica
Publicado em /11/2011 EN
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Stopping the spread of the cholera epidemic in Haiti required engaging community health workers (CHWs) in prevention and treatment activities. The Centers for Disease Control and Prevention collaborated with the Haitian Ministry of Public Health and Population to develop CHW educational materials, train >1,100 CHWs, and evaluate training efforts.

Green Power Grids: How Energy from Renewable Sources Affects Networks and Markets

Mureddu, Mario; Caldarelli, Guido; Chessa, Alessandro; Scala, Antonio; Damiano, Alfonso
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 03/09/2015 EN
Relevância na Pesquisa
16.06%
The increasing attention to environmental issues is forcing the implementation of novel energy models based on renewable sources. This is fundamentally changing the configuration of energy management and is introducing new problems that are only partly understood. In particular, renewable energies introduce fluctuations which cause an increased request for conventional energy sources to balance energy requests at short notice. In order to develop an effective usage of low-carbon sources, such fluctuations must be understood and tamed. In this paper we present a microscopic model for the description and for the forecast of short time fluctuations related to renewable sources in order to estimate their effects on the electricity market. To account for the inter-dependencies in the energy market and the physical power dispatch network, we use a statistical mechanics approach to sample stochastic perturbations in the power system and an agent based approach for the prediction of the market players’ behavior. Our model is data-driven; it builds on one-day-ahead real market transactions in order to train agents’ behaviour and allows us to deduce the market share of different energy sources. We benchmarked our approach on the Italian market...

An Auction-Based Method for Decentralized Train Scheduling

Parkes, David C.; Ungar, Lyle H.
Fonte: Association for Computing Machinery Publicador: Association for Computing Machinery
Tipo: Conference Paper
EN_US
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We present a computational study of an auction-based method for decentralized train scheduling. The method is well suited to the natural information and control structure of mod- ern railroads. We assume separate network territories, with an autonomous dispatch agent responsible for the ow of trains over each territory. Each train is represented by a self-interested agent that bids for the right to travel across the network from its source to destination, submitting bids to multiple dispatch agents along its route as necessary. The bidding language allows trains to bid for the right to enter and exit territories at particular times, and also to represent indifference over a range of times. Computational results on a simple network with straight-forward best-response bid- ding strategies demonstrate that the auction computes near- optimal system-wide schedules. In addition, the method appears to have useful scaling properties, both with the number of trains and with the number of dispatchers, and generates less extremal solutions than those obtained using traditional centralized optimization techniques.; Engineering and Applied Sciences

Improving the transfer experience at intermodal transit stations through innovative dispatch strategies

Desautels, Andrew T. (Andrew Thomas)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 169 p.
ENG
Relevância na Pesquisa
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This research introduces the concept of a bus hold light system that is based on headways of arriving trains in an effort to improve rail-to-bus transfer connectivity through a simple-to-implement, low-cost dispatching strategy. An analytical model and a simulation model are developed to analyze the impacts of the proposed headway-based hold light system on total passenger wait time and other relevant measures of transfer performance. The application of the two models to the cases of Alewife and Wellington Stations in the Massachusetts Bay Transportation Authority (MBTA) system and to 79 Street Station in the Chicago Transit Authority (CTA) system shows that the headway-based hold light system can produce substantial passenger wait time savings if implemented in an appropriate setting. Throughout these analyses, the sensitivity of the headway-based hold light system to various factors is analyzed, and the results obtained with the headway-based hold light system are compared with those obtained from the application of other bus dispatching strategies, most notably the strategy of holding each departing bus for passengers transferring from the next train arrival.; (cont.) Based on the case study results and sensitivity analyses, a set of guidelines for the implementation of headway-based hold light systems is proposed. In .the comparison of the headway-based hold light system and the hold-all-buses strategy...

Loco sheds, Harden, New South Wales

Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Formato: 21591008 bytes; Black and white photograph; 12.7cm x 20.5cm; image/tiff
EN_AU
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Photograph of railway yard with tracks in the foreground, various buildings in the background and wagons loaded with coal on the left. Two of the buildings have many chimneys and contain engines within their large openings. The long, high structure on the right surmounted by metal trusses is the coal stage where coal is loaded onto wagons. A number of lofty power and light poles are evident and on the ground are point levers for changing track directions. One source of the dark smoke on the horizon is a tall pipe. From the 1880s, Harden was an important railway junction with its own loco depot. In its heyday, around 1926, the depot employed 272 men, including fitters, to marshall and dispatch 40 trains a day. Cottages, shops and barracks were built near the station to serve this workforce. The Harden repair workshops closed in 1967.; Inscribed verso in ink: LOCO SHEDS HARDEN/ JAN 1932; alternative number: K2092; Ellis entered NSW Railways Service in 1882 and retired May 1924. He was a fitter and turner at the Eveleigh workshops and for 13 years was examining fitter and fitter in charge of the Sydney accident train. His career in the Railways was disrupted by an incident in 1909 when he was dismissed from his position because he had suggested to the NSW Railway Commissioner that some senior officers be removed. Ellis maintained they were negligent in their duties to the safety of the train-travelling public. On 25/3/12 a Select Committee recommended that Ellis be reinstated and compensed for losses. The last was done but Chief Commissioner Johnson did not reinstate him. It was only when Johnson left NSW in 1915 that Ellis was re-employed in the workshops. In July 1926 he was a witness in the coronial inquiry into the Aberdeen railway accident of 10/6/1926.

Empty houses, Harden, New South Wales

Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Formato: 19892080 bytes; Black and white photograph; 11.1cm x 19.5cm; image/tiff
EN_AU
Relevância na Pesquisa
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Photograph of a row of similar style cottages with timber walls and corrugated iron roofs. They have front verandahs, pointed roof features and outside toilets. The house on the right has a water tank. A paling and wire fence separates the allottments. A sheet of corrugated iron over one window and a sheet fallen from another attest to their abandonment. A windmill can be seen in the distance. These houses are probably a few of the many cottages that, like shops and barracks, were built near the railway station in order to accommodate the once large workforce that serviced the Harden loco depot. From the 1880s, Harden was an important railway junction and depot. In its heyday, around 1926, it employed 272 men, including fitters, to marshall and dispatch 40 trains a day. The repair workshops closed in 1967.; Inscribed verso in ink: EMPTY HOUSES HARDEN/DEC 1931; alternative number: K2; Ellis entered NSW Railways Service in 1882 and retired May 1924. He was a fitter and turner at the Eveleigh workshops and for 13 years was examining fitter and fitter in charge of the Sydney accident train. His career in the Railways was disrupted by an incident in 1909 when he was dismissed from his position because he had suggested to the NSW Railway Commissioner that some senior officers be removed. Ellis maintained they were negligent in their duties to the safety of the train-travelling public. On 25/3/12 a Select Committee recommended that Ellis be reinstated and compensed for losses. The last was done but Chief Commissioner Johnson did not reinstate him. It was only when Johnson left NSW in 1915 that Ellis was re-employed in the workshops. In July 1926 he was a witness in the coronial inquiry into the Aberdeen railway accident of 10/6/1926.

Empty houses and coal stage, Harden, New South Wales

Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Formato: 19623996 bytes; Black and white photograph; 11.1cm x 19.5cm; image/tiff
EN_AU
Relevância na Pesquisa
16.25%
Photograph of a row of cottages that back onto the railway yard. The timber houses have corrugated iron roofs and front verandahs with diagonal cross railings or vertical rails. A paling fence that runs in front is punctuated by white painted gates. In the background is the coal stage which loads coal onto trains. It is connected to a conveyor belt and is a long, high structure surmounted by metal trusses. These houses are probably a few of the many cottages that, like shops and barracks, were built near the railway station in order to accommodate the once large workforce that serviced the Harden loco depot. From the 1880s, Harden was an important railway junction and depot. In its heyday, around 1926, it employed 272 men, including fitters, to marshall and dispatch 40 trains a day. The repair workshops closed in 1967.; Inscribed verso in ink: EMPTY HOUSES AND COAL STAGE/ HARDEN DEC 1931; alternative number: K2094; Ellis entered NSW Railways Service in 1882 and retired May 1924. He was a fitter and turner at the Eveleigh workshops and for 13 years was examining fitter and fitter in charge of the Sydney accident train. His career in the Railways was disrupted by an incident in 1909 when he was dismissed from his position because he had suggested to the NSW Railway Commissioner that some senior officers be removed. Ellis maintained they were negligent in their duties to the safety of the train-travelling public. On 25/3/12 a Select Committee recommended that Ellis be reinstated and compensed for losses. The last was done but Chief Commissioner Johnson did not reinstate him. It was only when Johnson left NSW in 1915 that Ellis was re-employed in the workshops. In July 1926 he was a witness in the coronial inquiry into the Aberdeen railway accident of 10/6/1926.

Humphreville wins in Islip Sloop Race, newsclipping

Houston Post-Dispatch
Fonte: Houston Yacht Club via Rice University Publicador: Houston Yacht Club via Rice University
Tipo: newsclippings (information artifacts); Text
ENG
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17.5" x 23" newsclipping. Article begins" W.E. Humphreville, Jr. sailing his sloop "Jeanne" won the first race staged over the Houston Launch Club's race course off Sylvan Beachfor the new Islip class boats."

Houston Post Dispatch Trophy

Houston Yacht Club
Fonte: Houston Yacht Club via Rice University Publicador: Houston Yacht Club via Rice University
Tipo: photographs; Image
ENG
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original size black and white photograph 8''x10''; Photograph of Houston Post Dispatch Trophy for Opening Race of the Season. In 1924 Ross Sterling merged the Houston Dispatch with the Houston Post and the newspaper was known as the Houston Post Dispatch until the 1930s. This trophy, dedicated in 1930, is one of several donated to the Houston Yacht Club by the Houston Post.

Railways in Sub-Saharan Africa

World Bank
Fonte: World Bank Publicador: World Bank
Tipo: Economic & Sector Work :: Other Infrastructure Study
ENGLISH
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The changed role of rail in Africa over the last thirty years has seen it move from a situation where many of the systems were carrying a high share of their country's traffic to one in which their market share has declined, their assets have steadily deteriorated, their quality of service has reduced, and they are in many instances only a minor contributor to solving the transport problems of the continent. The first railways south of the Sahara were built in South Africa in the 1860's and 1870's, with lines heading inland from the ports at Cape Town and Durban. The networks in what were then Cape Province, Natal and Transvaal continued to develop but it was not until the turn of the twentieth century that large-scale railway development began in other parts of the continent. In almost every case, the pattern was the same, with isolated lines heading inland from a port to reach a trading centre or a mine, and a few branch lines then being built over a period of time. As almost all the lines were constructed under colonial administrations...

Green power grids: how energy from renewable sources affects network and markets

Mureddu, Mario; Caldarelli, Guido; Chessa, Alessandro; Scala, Antonio; Damiano, Alfonso
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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The increasing attention to environmental issues is forcing the implementation of novel energy models based on renewable sources, fundamentally changing the configuration of energy management and introducing new criticalities that are only partly understood. In particular, renewable energies introduce fluctuations causing an increased request of conventional energy sources oriented to balance energy requests on short notices. In order to develop an effective usage of low-carbon sources, such fluctuations must be understood and tamed. In this paper we present a microscopic model for the description and the forecast of short time fluctuations related to renewable sources and to their effects on the electricity market. To account for the inter-dependencies among the energy market and the physical power dispatch network, we use a statistical mechanics approach to sample stochastic perturbations on the power system and an agent based approach for the prediction of the market players behavior. Our model is a data-driven; it builds on one day ahead real market transactions to train agents behaviour and allows to infer the market share of different energy sources. We benchmark our approach on the Italian market finding a good accordance with real data.