958 resultados para Air traffic control -- Human factors


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Internet protocol TV (IPTV) is predicted to be the key technology winner in the future. Efforts to accelerate the deployment of IPTV centralized model which is combined of VHO, encoders, controller, access network and Home network. Regardless of whether the network is delivering live TV, VOD, or Time-shift TV, all content and network traffic resulting from subscriber requests must traverse the entire network from the super-headend all the way to each subscriber's Set-Top Box (STB).IPTV services require very stringent QoS guarantees When IPTV traffic shares the network resources with other traffic like data and voice, how to ensure their QoS and efficiently utilize the network resources is a key and challenging issue. For QoS measured in the network-centric terms of delay jitter, packet losses and bounds on delay. The main focus of this thesis is on the optimized bandwidth allocation and smooth datatransmission. The proposed traffic model for smooth delivering video service IPTV network with its QoS performance evaluation. According to Maglaris et al [5] First, analyze the coding bit rate of a single video source. Various statistical quantities are derived from bit rate data collected with a conditional replenishment inter frame coding scheme. Two correlated Markov process models (one in discrete time and one incontinuous time) are shown to fit the experimental data and are used to model the input rates of several independent sources into a statistical multiplexer. Preventive control mechanism which is to be include CAC, traffic policing used for traffic control.QoS has been evaluated of common bandwidth scheduler( FIFO) by use fluid models with Markovian queuing method and analysis the result by using simulator andanalytically, Which is measured the performance of the packet loss, overflow and mean waiting time among the network users.

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IPTV is now offered by several operators in Europe, US and Asia using broadcast video over private IP networks that are isolated from Internet. IPTV services rely ontransmission of live (real-time) video and/or stored video. Video on Demand (VoD)and Time-shifted TV are implemented by IP unicast and Broadcast TV (BTV) and Near video on demand are implemented by IP multicast. IPTV services require QoS guarantees and can tolerate no more than 10-6 packet loss probability, 200 ms delay, and 50 ms jitter. Low delay is essential for satisfactory trick mode performance(pause, resume,fast forward) for VoD, and fast channel change time for BTV. Internet Traffic Engineering (TE) is defined in RFC 3272 and involves both capacity management and traffic management. Capacity management includes capacityplanning, routing control, and resource management. Traffic management includes (1)nodal traffic control functions such as traffic conditioning, queue management, scheduling, and (2) other functions that regulate traffic flow through the network orthat arbitrate access to network resources. An IPTV network architecture includes multiple networks (core network, metronetwork, access network and home network) that connects devices (super head-end, video hub office, video serving office, home gateway, set-top box). Each IP router in the core and metro networks implements some queueing and packet scheduling mechanism at the output link controller. Popular schedulers in IP networks include Priority Queueing (PQ), Class-Based Weighted Fair Queueing (CBWFQ), and Low Latency Queueing (LLQ) which combines PQ and CBWFQ.The thesis analyzes several Packet Scheduling algorithms that can optimize the tradeoff between system capacity and end user performance for the traffic classes. Before in the simulator FIFO,PQ,GPS queueing methods were implemented inside. This thesis aims to implement the LLQ scheduler inside the simulator and to evaluate the performance of these packet schedulers. The simulator is provided by ErnstNordström and Simulator was built in Visual C++ 2008 environmentand tested and analyzed in MatLab 7.0 under windows VISTA.

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Traffic Control Signs or destination boards on roadways offer significant information for drivers. Regulation signs tell something like your speed, turns, etc; Warning signs warn drivers of conditions ahead to help them avoid accidents; Destination signs show distances and directions to various locations; Service signs display location of hospitals, gas and rest areas etc. Because the signs are so important and there is always a certain distance from them to drivers, to let the drivers get information clearly and easily even in bad weather or other situations. The idea is to develop software which can collect useful information from a special camera which is mounted in the front of a moving car to extract the important information and finally show it to the drivers. For example, when a frame contains on a destination drive sign board it will be text something like "Linkoping 50",so the software should extract every character of "Linkoping 50", compare them with the already known character data in the database. if there is extracted character match "k" in the database then output the destination name and show to the driver. In this project C++ will be used to write the code for this software.

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Internet protocol TV (IPTV) is predicted to be the key technology winner in the future. Efforts to accelerate the deployment of IPTV centralized model which is combined of VHO, encoders, controller, access network and Home network. Regardless of whether the network is delivering live TV, VOD, or Time-shift TV, all content and network traffic resulting from subscriber requests must traverse the entire network from the super-headend all the way to each subscriber's Set-Top Box (STB). IPTV services require very stringent QoS guarantees When IPTV traffic shares the network resources with other traffic like data and voice, how to ensure their QoS and efficiently utilize the network resources is a key and challenging issue. For QoS measured in the network-centric terms of delay jitter, packet losses and bounds on delay. The main focus of this thesis is on the optimized bandwidth allocation and smooth data transmission. The proposed traffic model for smooth delivering video service IPTV network with its QoS performance evaluation. According to Maglaris et al [5] first, analyze the coding bit rate of a single video source. Various statistical quantities are derived from bit rate data collected with a conditional replenishment inter frame coding scheme. Two correlated Markov process models (one in discrete time and one in continuous time) are shown to fit the experimental data and are used to model the input rates of several independent sources into a statistical multiplexer. Preventive control mechanism which is to be including CAC, traffic policing used for traffic control. QoS has been evaluated of common bandwidth scheduler( FIFO) by use fluid models with Markovian queuing method and analysis the result by using simulator and analytically, Which is measured the performance of the packet loss, overflow and mean waiting time among the network users.

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The rapid growth of urban areas has a significant impact on traffic and transportation systems. New management policies and planning strategies are clearly necessary to cope with the more than ever limited capacity of existing road networks. The concept of Intelligent Transportation System (ITS) arises in this scenario; rather than attempting to increase road capacity by means of physical modifications to the infrastructure, the premise of ITS relies on the use of advanced communication and computer technologies to handle today’s traffic and transportation facilities. Influencing users’ behaviour patterns is a challenge that has stimulated much research in the ITS field, where human factors start gaining great importance to modelling, simulating, and assessing such an innovative approach. This work is aimed at using Multi-agent Systems (MAS) to represent the traffic and transportation systems in the light of the new performance measures brought about by ITS technologies. Agent features have good potentialities to represent those components of a system that are geographically and functionally distributed, such as most components in traffic and transportation. A BDI (beliefs, desires, and intentions) architecture is presented as an alternative to traditional models used to represent the driver behaviour within microscopic simulation allowing for an explicit representation of users’ mental states. Basic concepts of ITS and MAS are presented, as well as some application examples related to the subject. This has motivated the extension of an existing microscopic simulation framework to incorporate MAS features to enhance the representation of drivers. This way demand is generated from a population of agents as the result of their decisions on route and departure time, on a daily basis. The extended simulation model that now supports the interaction of BDI driver agents was effectively implemented, and different experiments were performed to test this approach in commuter scenarios. MAS provides a process-driven approach that fosters the easy construction of modular, robust, and scalable models, characteristics that lack in former result-driven approaches. Its abstraction premises allow for a closer association between the model and its practical implementation. Uncertainty and variability are addressed in a straightforward manner, as an easier representation of humanlike behaviours within the driver structure is provided by cognitive architectures, such as the BDI approach used in this work. This way MAS extends microscopic simulation of traffic to better address the complexity inherent in ITS technologies.

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O calor, no ambiente onde o ser humano vive ou trabalha, atribui-se a: -fatores físicos: relação entre temperatura, radiação, umidade e movimento do ar; fatores humanos: o ser humano atua como fonte de energia através de seu metabolismo e atividade física. o calor caracterizado por um determinado meio ambiente é o resultado da atuação de diferentes variáveis, tais como: sistema de construção, situação geográfica do ambiente físico, climatização artificial, etc.; idade, sexo, capacidade física, estado de aclimatação, vestuário, tipo, carga e regime de trabalho, etc. A partir do momento em que o indivíduo for introduzido num determinado meio ambiente térmico, todos estes fatores vão influenciar a transmissão de calor entre ele e o ambiente. Na pretensão de haver equilíbrio térmico no meio ambiente quente, constata-se a necessidade de providenciar medidas de proteção a nível do sujeito e do ambiente, para que prevaleçam situações ambientais "confortáveis", ou pelo menos, "tolerantes". Desse modo, através da: definição das condições térmicas tolerantes e de conforto, parte-se para projetar meios ambientes de trabalho, que tornem praticáveis um isolamento térmico do calor exterior, assim como a perda de calor de dentro para fora. Atuando-se sobre variáveis individuais e ambientais estaremos incidindo diretamente sobre os meios de transmissão, procurando-se diminuir a quantidade de calor que o organismo produz e/ou recebe e aumentar a possibilidade de dissipá-lo.

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O presente trabalho investiga a possibilidade de aumentar o espectro de participação política na Administração, pela consideração de que o Estado brasileiro tem fins, objetivos a realizar e é uma democracia do tipo “procedimental-deliberativa”, em que o povo deve participar das decisões que afetem sua vida. Além disso, a realização do interesse geral só tem a ganhar em eficácia se as decisões estatais escaparem, o mais possível, da lógica tecnocrática do “segredo administrativo”, porque, graças à participação dos interessados, pelo conhecimento dos dados concretos e dos fatores humanos e técnicos que condicionam uma decisão, estes podem trazer algum elemento que a modifique, obrigando a Administração a explicar os motivos de sua ação, facilitando, assim, a execução. Por isso, estuda-se, tanto o significado do princípio democrático quanto do princípio da publicidade, as formas possíveis de participação dos cidadãos na Administração e as concretizações da publicidade administrativa em direito de saber, direito de controle e direito de participar do processo administrativo.

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The São Paulo State has 36 million people, 25 million living in three metropolitan areas. Only the São Paulo Metropolitan Region (SPMR) includes the state capital (São Paulo City) plus 38 cities, where ≈ 18 million people live, affected by frequent episodes of ozone, NOx, and fine particulate matter. In 2003, it was estimated that 15.1% of the SPMR vehicles used ethanol and 70.2% used the local gasoline. Natural gas vehicles have witnessed a booming participation in the last years, mainly through conversion of gasoline cars, and the present fleet is almost one million vehicles. To face the problems generated by light vehicles emissions the Federal Government set a program called PROCONVE - Program of Air Pollution Control from Vehicles - in 1986 and since then until now a significant reduction was reached, but the growth of the fleet hides most of the emission cuts. A discussion covers the evolution of the air pollution management in São Paulo; and innovative tools for air pollution management - both for mobile and stationary sources. This is an abstract of a paper presented at the 98th AWMA Annual Conference and Exhibition (Minneapolis, MN 6/21-24/2005).

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The risk for venous thromboembolism (VTE) in medical patients is high, but risk assessment is rarely performed because there is not yet a good method to identify candidates for prophylaxis. Purpose: To perform a systematic review about VTE risk factors (RFs) in hospitalized medical patients and generate recommendations (RECs) for prophylaxis that can be implemented into practice. Data sources: A multidisciplinary group of experts from 12 Brazilian Medical Societies searched MEDLINE, Cochrane, and LILACS. Study selection: Two experts independently classified the evidence for each RF by its scientific quality in a standardized manner. A risk-assessment algorithm was created based on the results of the review. Data synthesis: Several VTE RFs have enough evidence to support RECs for prophylaxis in hospitalized medical patients (eg, increasing age, heart failure, and stroke). Other factors are considered adjuncts of risk (eg, varices, obesity, and infections). According to the algorithm, hospitalized medical patients ≥40 years-old with decreased mobility, and ≥1 RFs should receive chemoprophylaxis with heparin, provided they don't have contraindications. High prophylactic doses of unfractionated heparin or low-molecular-weight-heparin must be administered and maintained for 6-14 days. Conclusions: A multidisciplinary group generated evidence-based RECs and an easy-to-use algorithm to facilitate VTE prophylaxis in medical patients. © 2007 Rocha et al, publisher and licensee Dove Medical Press Ltd.

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This paper presents an application to traffic lights control in congested urban traffic, in real time, taking as input the position and route of the vehicles in the involved areas. This data is obtained from the communication between vehicles and infrastructure (V2I). Due to the great complexity of the possible combination of traffic lights and the short time to get a response, Genetic Algorithm was used to optimize this control. According to test results, the application can reduce the number of vehicles in congested areas, even with the entry of vehicles that previously were not being considered in these roads, such as parked vehicles. © 2012 IEEE.

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The ALADI - ECLAC Seminar Latin American Association for Integration - Economic Commission for Latin America and the Caribbean Santiago, Chile, 15-17 April, 1997 Experts from the public and private sectors of Brazil, Chile, Colombia, Paraguay, Peru, Uruguay, and Venezuela participated on a private basis in an open debate. Representatives from the International Association of Latin American Air Transport (AITAL), the Latin American Civil Aviation Commission (CLAC), and the International Civil Aviation Organization (OACI) also attended the meeting.The topics analyzed in the Seminar were: 1. The situation and prospects for international air-transport: policies and tendencies in the United States and the European Union. 2. South American sub-regional agreements. 3. The evolution of national policies in the region. 4. Structural changes in corporate management. 5. The use of commercial air-traffic rights. 6. Security in air-navigation. 7. The challenges facing regional airlines.

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Traffic congestion has become a severe scourge in large cities, in both the industrialized and developing countries. Increasing demand for urban transport and transit has led to longer travel times, and a greater incidence of accidents, environmental problems and deterioration in the quality of life than is considered acceptable for citizens. A multidisciplinary approach is required in order to keep the negative effects of congestion under control and to ensure standards of living remain sustainable. In view of the seriousness of the problem, ECLAC with the support of the German Agency for Technical Cooperation (GTZ) is carrying out a project to study measures that contribute to traffic control. As part of this project, initiatives regarding the supply of, and the demand for, transport have been examined, and a programme to disseminate information is being conducted.For further information, please contact Mr Alberto Bull .

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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We evaluated the effects of cigarette smoke (CS) on lung inflammation and remodeling in a model of ovalbumin (OVA)-sensitized and OVA-challenged mice. Male BALB/c mice were divided into 4 groups: non-sensitized and air-exposed (control); non-sensitized and exposed to cigarette smoke (CS), sensitized and air-exposed (OVA) (50 mu g + OVA 1% 3 times/week for 3 weeks) and sensitized and cigarette smoke exposed mice (OVA + CS). IgE levels were not affected by CS exposure. The increases in total bronchoalveolar fluid cells in the OVA group were attenuated by co-exposure to CS, as were the changes in IL-4, IL-5, and eotaxin levels as well as tissue elastance (p < 0.05). In contrast, only the OVA + CS group showed a significant increase in the protein expression of IFN-gamma, VEGF, GM-CSF and collagen fiber content (p < 0.05). In our study, exposure to cigarette smoke in OVA-challenged mice resulted in an attenuation of pulmonary inflammation but led to an increase in pulmonary remodeling and resulted in the dissociation of airway inflammation from lung remodeling. (C) 2012 Elsevier B.V. All rights reserved.