820 resultados para Road infrastructure


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In recent years there has been renewed interest in using preventive maintenance techniques to extend pavement life and to ensure low life cycle costs for our road infrastructure network. Thin maintenance surfaces can be an important part of a preventive maintenance program for asphalt cement concrete roads. The Iowa Highway Research Board has sponsored Phase Two of this research project to demonstrate the use of thin maintenance surfaces in Iowa and to develop guidelines for thin maintenance surface uses that are specific to Iowa. This report documents the results of test section construction and monitoring started in Phase One and continued in Phase Two. The report provides a recommended seal coat design process based on the McLeod method and guidance on seal coat aggregates and binders. An update on the use of local aggregates for micro-surfacing in Iowa is included. Winter maintenance guidelines for thin maintenance surfaces are reported herein. Finally, Phase One's interim, qualitative thin maintenance surface guidelines are supplemented with Phase two's revised, quantitative guidelines. When thin maintenance surfaces are properly selected and applied, they can improve the pavement surface condition index and the skid resistance of pavements. For success to occur, several requirements must be met, including proper material selection, design, application rate, workmanship, and material compatibility, as well as favorable weather during application and curing. Specific guidance and recommendations for many types of thin maintenance surfaces and conditions are included in the report.

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A water quality resource concern has come to the forefront in the Upper Miller Creek watershed in Black Hawk County after five to seven inches of rain fell on the area on May 22nd and 23rd of 2004 and unprecedented amounts of soil and organic debris were washed from cultivated areas, clogging most culverts and roadside ditches. The quantity of soil deposited in ditches gave a good indication of the amounts that were transported into the stream. The estimated total cost to Black Hawk County for cleanup and repair within the road right-of-way was $345,000. There were undetermined environmental costs incurred when the incredibly high volumes of soil washed from the fields into Miller Creek which flows directly into the Cedar River that is identified by the Department of Natural Resources as an impaired water body. The Upper Miller Creek Watershed Project is an innovative, collaborative project intended to meet a specific need identified by a local steering committee made up of concerned community agencies and local landowners. Led by the Soil and Water Conservation District and the Black Hawk County Board of Supervisors, the Miller Creek Watershed Project seeks to reduce soil erosion, improve water quality, and reduce county road infrastructure cost by implementing conservation practices, reducing nutrient and pesticide use and improving wildlife habitat.

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This paper analyzes the effects of parliamentary representation on road infrastructure expenditure during the Spanish Restoration. Using a panel dataset of Spanish provinces in 1880-1914 we find that the allocation of administrative resources among provinces depended both on the delegation characteristics (such as the share of MPs with party leadership positions, and their degree of electoral independence), and the regime"s global search for stability. These results point to the importance of electoral dynamics within semi-democratic political systems, and offer an example of the influence of government tactics on infrastructure allocation.

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This paper analyzes the effects of parliamentary representation on road infrastructure expenditure during the Spanish Restoration. Using a panel dataset of Spanish provinces in 1880-1914 we find that the allocation of administrative resources among provinces depended both on the delegation characteristics (such as the share of MPs with party leadership positions, and their degree of electoral independence), and the regime"s global search for stability. These results point to the importance of electoral dynamics within semi-democratic political systems, and offer an example of the influence of government tactics on infrastructure allocation.

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Maritime transport is the foundation for trade in the Baltic Sea area. It represents over 15% of the world’s cargo traffic and it is predicted to increase by over 100% in the future. There are currently over 2,000 ships sailing on the Baltic Sea and both the number and the size of ships have been growing in recent years. Due to the importance of maritime traffic in the Baltic Sea Region, ports have to be ready to face future challenges and adapt to the changing operational environment. The companies within the transportation industry – in this context ports, shipowners and logistics companies – compete continuously and although the number of companies in the business is not particularly substantial because the products offered are very similar, other motives for managing the supply chain arise. The factors creating competitive advantage are often financial and related to cost efficiency, but geographical location, road infrastructure in the hinterland and vessel connections are among the most important factors. The PENTA project focuses on adding openness, transparency and sharing knowledge and information, so that the challenges of the future can be better addressed with regard to cooperation. This report presents three scenario-based traffic forecasts for routes between the PENTA ports in 2020. The chosen methodology is PESTE, in which the focus in on economic factors affecting future traffic flows. The report further analyses the findings and results of the first PENTA WP2 report “Drivers of demand in cargo and passenger traffic between PENTA ports” and utilises the same material, which was obtained through interviews and mail surveys.

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Logistics infrastructure and transportation services have been the liability of countries and governments for decades, or these have been under strict regulation policies. One of the first branches opened for competition in EU as well as in other continents, has been air transports (operators, like passenger and freight) and road transports. These have resulted on lower costs, better connectivity and in most of the cases higher service quality. However, quite large amount of other logistics related activities are still directly (or indirectly) under governmental influence, e.g. railway infrastructure, road infrastructure, railway operations, airports, and sea ports. Due to the globalization, governmental influence is not that necessary in this sector, since transportation needs have increased with much more significant phase as compared to economic growth. Also freight transportation needs do not correlate with passenger side, due to the reason that only small number of areas in the world have specialized in the production of particular goods. Therefore, in number of cases public-private partnership, or even privately owned companies operating in these sub-branches have been identified as beneficial for countries, customers and further economic growth. The objective of this research work is to shed more light on these kinds of experiments, especially in the relatively unknown sub-branches of logistics like railways, airports and sea container transports. In this research work we have selected companies having public listed status in some stock exchange, and have needed amount of financial scale to be considered as serious company rather than start-up phase venture. Our research results show that railways and airports usually need high fixed investments, but have showed in the last five years generally good financial performance, both in terms of profitability and cash flow. In contrary to common belief of prosperity in globally growing container transports, sea vessel operators of containers have not shown that impressive financial performance. Generally margins in this business are thin, and profitability has been sacrificed in front of high growth – this also concerns cash flow performance, which has been lower too. However, as we examine these three logistics sub-branches through shareholder value development angle during time period of 2002-2007, we were surprised to find out that all of these three have outperformed general stock market indexes in this period. More surprising is the result that financially a bit less performing sea container transportation sector shows highest shareholder value gain in the examination period. Thus, it should be remembered that provided analysis shows only limited picture, since e.g. dividends were not taken into consideration in this research work. Therefore, e.g. US railway operators have disadvantage to other in the analysis, since they have been able to provide dividends for shareholders in long period of time. Based on this research work we argue that investment on transportation/logistics sector seems to be safe alternative, which yields with relatively low risk high gain. Although global economy would face smaller growth period, this sector seems to provide opportunities in more demanding situation as well.

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La rapide progression des technologies sans fil au cours de ces dernières années a vu naître de nouveaux systèmes de communication dont les réseaux véhiculaires. Ces réseaux visent à intégrer les nouvelles technologies de l’information et de la communication dans le domaine automobile en vue d’améliorer la sécurité et le confort sur le réseau routier. Offrir un accès Internet aux véhicules et à leurs occupants peut sans doute aider à anticiper certains dangers sur la route tout en rendant plus agréables les déplacements à bord des véhicules. Le déploiement de ce service nécessite que des messages soient échangés entre les véhicules. Le routage constitue un élément crucial dans un réseau, car définissant la façon dont les différentes entités échangent des messages. Le routage dans les VANETS constitue un grand défi car ces derniers sont caractérisés par une forte mobilité entraînant une topologie très dynamique. Des protocoles ont été proposés pour étendre Internet aux réseaux véhiculaires. Toutefois, la plupart d’entre eux nécessitent un coût élevé de messages de contrôle pour l’établissement et le maintien des communications. Ceci a pour conséquence la saturation de la bande passante entrainant ainsi une baisse de performance du réseau. Nous proposons dans ce mémoire, un protocole de routage qui s’appuie sur des passerelles mobiles pour étendre Internet aux réseaux véhiculaires. Le protocole prend en compte la mobilité des véhicules et la charge du réseau pour l’établissement et le maintien des routes.

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Se realiza un análisis de riesgo prospectivo para determinar los posibles efectos socioeconómicos (población, vivienda, infraestructura económica y vial principal y el producto interno bruto) del aumento del nivel del mar en la cabecera urbana de la Isla de San Andrés, Colombia. Como alternativa a los resultados críticos, se plantean tres modelos de ocupación del territorio que podrían reducir la vulnerabilidad del asentamiento humano.

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Teniendo en cuenta la importancia de la infraestructura de transporte en el desarrollo económico, ya que de esta depende el intercambio de bienes y servicios dentro y fuera del país, y dado el entorno de globalización de mercados, se hace relevante hacer un diagnóstico de la evolución de la inversión en infraestructura de transportes en Colombia durante los últimos años. El análisis de la actividad de transporte dentro del Producto Interno Bruto Nacional a lo largo del periodo 2002 - 2010, muestra un aporte importante al mismo, confirmando así la relevancia que tiene el sector de transporte en la economía del país. El modo de transporte que cobra más importancia es el transporte por carreteras pues es el medio más utilizado en Colombia, tanto para mercancías como para pasajeros, por lo cual se enfatiza en la inversión y evolución de la infraestructura vial. En este contexto se presenta un estudio de la legislación del sector, los principales proyectos ejecutados durante la última década, los objetivos propuestos por cada uno de estos y el estado actual de los mismos.

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En la actualidad, la actividad económica de Colombia se divide en sectores y subsectores que contribuyen al crecimiento del país en términos mercantiles. Al no existir un estudio sobre la logística en cada uno de estos, muchas condiciones favorables para el desarrollo económico tales como la excelente ubicación del país, puertos estratégicamente localizados que facilitan el comercio exterior y demás, se desaprovechan y no permiten a las empresas lograr un mayor control respecto al flujo tanto de productos como de información. Ahora bien, para la movilización de los productos de cada sector se debe hacer uso de transporte terrestre, marítimo, aéreo o sistemas multimodales que sean manejados de la forma más eficiente. Sin embargo, por términos de infraestructura vial en caso del transporte terrestre, las empresas deben incurrir en altos costos que afectan todo el rendimiento de la cadena de valor, no solo a nivel monetario sino también en tiempos de respuesta. Poder evidenciar el impacto de la infraestructura vial interna en la cadena de suministro, además de las diferentes etapas que se deben tener en cuenta para el comercio a nivel internacional, permitiría a los empresarios de los diferentes sectores económicos en Colombia, poder desarrollar planes de mejora en sus procesos internos y externos, así como prósperas relaciones con clientes. Adicionalmente, respecto a los procesos de exportación, la diversificación de mercados y productos contribuye a un mejor aprovechamiento de tratados de libre comercio, factor que favorece la competitividad y la posibilidad de alianzas estratégicas que permitan hacer frente a la globalización de la economía, que a su vez asegura la perdurabilidad de una empresa en cada uno de los sectores estudiados. El desarrollo de este proyecto permitirá no solamente conocer los costos promedio en los que se incurre para movilizar productos según las condiciones de las cadenas de valor de cada sector, sino también las rutas alternativas que puede tomar la mercancía con el fin de lograr una efectividad del proceso del transporte y de igual forma, tomar medidas respecto a la competitividad de una empresa a nivel de almacenamiento y distribución.

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Introducción: Los conductores de transporte público, están expuesto a factores de riesgo ergonómicos y de condiciones de trabajo que pueden estar asociados a la aparición de síntomas osteomusculares, afectando su estado de salud. Objetivo: evaluar los factores de riesgo ergonómico y las condiciones de trabajo asociadas a sintomatología osteomuscular en conductores de una cooperativa del sector de transporte público. Metodología: estudio de corte transversal realizado a 158 conductores. La evaluación de las condiciones de trabajo se realizó por medio de la “Encuesta Nacional de Condiciones de Trabajo” y para la identificación de los síntomas y factores de riesgo ergonómicos, se usó el “Cuestionario Ergopar”. Resultados: La prevalencia de los síntomas osteomusculares fue mayor en espalda lumbar (41.1%), seguida del síntoma en cuello, hombros y/o espalda dorsal (36.7%). los factores asociados significativamente con la prevalencia de síntomas osteomusculares en cuello/hombros y/o espalda dorsal fueron: edad (p= 0.04) y el movimiento que realiza el cuello y la cabeza (p= 0.039); en espalda lumbar: intensidad del esfuerzo físico (p=0.011) y la frecuencia con la que la iluminación les permitía trabajar en una postura adecuada (p=0.025); en manos y muñecas: puesto de trabajo (p= 0.019), acción que realizan con las manos (p= 0.019), peso que manipulan (p=0.028), la frecuencia de huecos, aberturas, escaleras, plataformas y desniveles (p=0.021). Conclusiones: La morbilidad osteomuscular presentó una asociación mayor con las condiciones no ergonómicas (postura, manipulación de carga, movimientos repetitivos) y condiciones de trabajo (infraestructura de vías, velocidad del trabajo, plazos y metas para realizar el trabajo).

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Esta tese oferece uma explicação para a existência de políticas governamentais que não alcançam estabilidade após conjunturas críticas que afetam seu equilíbrio, enfocando a gestão da infraestrutura rodoviária no Brasil. A política do setor entrou em crise financeira e institucional em meados da década de 70, que se acentuou na década de 80, pressionando os Governos democráticos a perseguiram uma agenda de reformas que envolviam a revisão dos mecanismos de financiamento e investimento públicos, a mudança estrutural dos órgãos e competências do setor e a parceria com o mercado, através de políticas de concessões rodoviárias. Através de estudos de caso dos Governos da Nova República entre os anos de 1985 e 2010, a pesquisa responde o porquê de as reformas intentadas no setor apresentarem uma seqüência de falhas e sucesso parciais, proporcionando novos desequilíbrios e tentativas de reforma. Por intermédio do referencial teórico do institucionalismo, demonstramos que as transformações institucionais ocorridas no Brasil a partir do fim da década de 70 contribuíram para a configuração de um setor mais pluralista e sob menor autonomia dos órgãos setoriais, levando a contradições institucionais com as quais os sucessivos Governos lidaram sob dilemas estratégicos entre manter a governabilidade política e perseguir um bom desempenho. Esta interação entre um setor competitivo e estratégias políticas conduziu a um equilíbrio desarticulado, que sacrifica o desempenho setorial e demanda permanentes agendas de reformas.

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As concessões e as Parcerias Público-Privadas (PPP) são mecanismos cada vez mais utilizados pelo setor público para alavancar os investimentos em infraestrutura no país. Para que haja viabilidade econômica das mesmas, as suas taxas internas de retorno (TIR) apresentam-se como variáveis que precisam refletir os riscos e a realidade do negócio. O presente estudo busca analisar as taxas de retorno utilizadas para a modelagem das tarifas-teto do setor de rodovias federais frente às especificidades do seu mercado. Para tal, são seguidas três frentes: a primeira é analisar a metodologia da taxa de retorno utilizada para a modelagem das concessões mais recentes de rodovias; a segunda é estimar uma taxa de retorno a partir de pesquisa bibliográfica; e a terceira é, por meio de dados de rentabilidade de balanços de concessionárias do setor, observar se as taxas de retorno das primeiras concessões foram devidamente calculadas na época. Na dissertação, concluímos que a atual metodologia da taxa de retorno do Tesouro Nacional pode ser aprimorada, principalmente em relação aos parâmetros de grau de alavancagem e capital de terceiros, e observamos que a taxa de retorno tem se aproximado do custo de oportunidade do setor ao longo das últimas etapas de concessão. O estudo visa contribuir para o debate sobre a rentabilidade dos projetos de infraestrutura rodoviária, em meio a um período de intensos investimentos no setor.

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The search for a sustainable urban mobility, has recast the public policy of transport and movement for all, in order to contribute to the welfare economic, social and environmental. Within this context, has as its main objective review here in the city of Natal in the state of Rio Grande Norte, the deployment of the new road infrastructure of the transport corridor of Bernardo Vieira Avenue and checking at least with regard to urban areas and environmental chosen here, as will indicators to assess sustainable urban mobility, that the theory has been well constructed, but in practice little way to apply the proposed guidelines for sustainability. To achieve this result, is initially a literature review with the principal investigators of the matter, since the concepts of indicators of sustainable urban mobility. And a second time, participating in to the case study, using the methodology of environmental awareness, through analysis photographs, notes and testimony in the study area ace to reach conclusions

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)