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Human Error Contribution in Collision and Grounding of Oil Tankers

MARTINS, Marcelo Ramos; MATURANA, Marcos Coelho
Fonte: WILEY-BLACKWELL PUBLISHING, INC Publicador: WILEY-BLACKWELL PUBLISHING, INC
Tipo: Artigo de Revista Científica
Português
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The purpose of this article is to present a quantitative analysis of the human failure contribution in the collision and/or grounding of oil tankers, considering the recommendation of the ""Guidelines for Formal Safety Assessment"" of the International Maritime Organization. Initially, the employed methodology is presented, emphasizing the use of the technique for human error prediction to reach the desired objective. Later, this methodology is applied to a ship operating on the Brazilian coast and, thereafter, the procedure to isolate the human actions with the greatest potential to reduce the risk of an accident is described. Finally, the management and organizational factors presented in the ""International Safety Management Code"" are associated with these selected actions. Therefore, an operator will be able to decide where to work in order to obtain an effective reduction in the probability of accidents. Even though this study does not present a new methodology, it can be considered as a reference in the human reliability analysis for the maritime industry, which, in spite of having some guides for risk analysis, has few studies related to human reliability effectively applied to the sector.

Synchronous collision malignant melanoma and adenocarcinoma of the rectum

DIAS, A. R.; PINTO, R. A.; MORY, E.; SILVA, I. C.; SIQUEIRA, S. A. C.; NAHAS, S. C.; CECCONELLO, I.; WEXNER, S. D.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
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Collision tumors consist of two independent but coexisting tumors. This uncommon situation might be easily mistaken for a composite tumor where one histogenetic event originates from two apparently distinct neoplasms. Colorectal collisions are particularly unusual; here, we report the exceedingly rare case of a 61-year-old man with malignant melanoma and adenocarcinoma colliding in the rectum. Collision tumors have an idiopathic pathophysiology and in fact ""accidental meeting"" is accepted by many authors. This article discusses the concepts about cancer development, which are overlooked by this hypothesis, another theory to explain that this rare occurrence involves microenvironment changes.

Aplicação de Redes Bayesianas na análise da contribuição do erro humano em acidentes de colisão.; Application of Bayesian Networks in the human error contribution analysis of collision accidents.

Maturana, Marcos Coelho
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 04/02/2010 Português
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Recentemente, na indústria naval, a normatização por sociedades classificadoras e pela IMO (International Maritime Organization) tem apresentado uma mudança paulatina, migrando dos procedimentos prescritivos para uma estrutura regulatória baseada em risco. Tal perspectiva oferece algumas vantagens para operadores e armadores (empresas que exploram comercialmente as embarcações): 1) maior capacidade de incorporar projetos inovadores, tecnicamente superiores, a custos aceitáveis; 2) maior confiança quanto à segurança; 3) melhor entendimento de eventos de periculosidade, dos riscos enfrentados em novos projetos e de medidas de mitigação. Especificamente no setor petrolífero, a análise, a avaliação e o gerenciamento de risco são vitais, em face da potencial gravidade dos acidentes no que diz respeito à vida humana, ao meio-ambiente e ao patrimônio. Dado que a maior parte dos acidentes nesta área são motivados por fatores humanos, o propósito deste trabalho é apresentar uma metodologia e técnicas eficientes de análise de confiabilidade humana aplicáveis a esta indústria. Durante as últimas décadas, se desenvolveram várias técnicas para o estudo quantitativo da confiabilidade humana. Na década de oitenta foram desenvolvidas técnicas que modelam o sistema por meio de árvores binárias...

Estimação de probabilidade de colisão com obstáculos móveis para navegação autônoma; Mobile obstacle collision probability estimation for autonomous navigation

Sant'Ana, Felipe Taha
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 01/07/2015 Português
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Na área de robótica móvel autônoma é importante que o robô siga uma trajetória livre de obstáculos. Estes podem ser desde obstáculos estáticos, como paredes e cadeiras em um ambiente interno, ou mesmo obstáculos móveis, como pessoas caminhando na calçada e carros passando pela rua, quando consideramos ambientes externos. No caso de um ambiente estático, o problema pode ser resolvido planejando uma trajetória livre de colisões, sendo que não é necessário um replanejamento se todos os obstáculos estáticos foram considerados. Para ambientes onde os obstáculos estão em constante movimento, é necessário um constante replanejamento da trajetória para que se evite colisões. Alternativamente, pode ser verificada a possibilidade de se manter na rota planejada, alterando apenas a velocidade de cruzeiro do robô para que este desvie dos obstáculos móveis. Este trabalho propõe uma metodologia para calcular uma velocidade de cruzeiro para o robô de forma a minimizar a probabilidade de colisão com os obstáculos detectados pelos seus sensores. A escolha da variação de velocidade para o robô considera a sua velocidade atual, e as velocidades estimadas para os obstáculos. A metodologia para resolução deste problema é apresentada considerando incertezas na posição do robô e obstáculos. São apresentados resultados de simulação que exemplificam a aplicação da metodologia.; Following a free path is an important issue in the area of autonomous mobile robotics. The obstacles can be anything from walls and chairs in an indoor environment...

Possibility of collision between co-orbital asteroids and the Earth

Domingos, R. C.; Winter, O. C.
Fonte: Sociedade Brasileira de Matemática Aplicada e Computacional Publicador: Sociedade Brasileira de Matemática Aplicada e Computacional
Tipo: Artigo de Revista Científica Formato: 99-107
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Considering hypothetical co-orbital asteroids with the Earth, Tatum (1997) presented a study about the necessary radial distance in order to produce collision. He adopted an analysis considering a composition of circular two-body systems, Sun-Earth and Sun-Asteroid. He found that asteroids with radial positions between 0.9943 and 1.0057 AU would necessarily collide with the Earth. In the present work, we show that this problem cannot be treated in this way. Adopting the circular restricted three-body problem, we verified that asteroids in the supposed region of collision with the Earth have stable horseshoe trajectories. Therefore, in the co-orbital region the dynamical system has to be studied as a restricted three-body problem since the composition of two-body problems gives a misleading result.

LGMD based neural network for automatic collision detection

Silva, Ana; Silva, Jorge Bruno; Santos, Cristina
Fonte: SciTePress Publicador: SciTePress
Tipo: Conferência ou Objeto de Conferência
Publicado em //2012 Português
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Real-time collision detection in dynamic scenarios is a hard task if the algorithms used are based on conventional techniques of computer vision, since these are computationally complex and, consequently, time-consuming. On the other hand, bio-inspired visual sensors are suitable candidates for mobile robot navigation in unknown environments, due to their computational simplicity. The Lobula Giant Movement Detector (LGMD) neuron, located in the locust optic lobe, responds selectively to approaching objects. This neuron has been used to develop bio-inspired neural networks for collision avoidance. In this work, we propose a new LGMD model based on two previous models, in order to improve over them by incorporating other algorithms. To assess the real-time properties of the proposed model, it was applied to a real robot. Results shown that the LGMD neuron model can robustly support collision avoidance in complex visual scenarios.

Joint design of RFID reader and tag anti-collision algorithms: a cross-layer approach

Gameiro, Atílio; Samano, Ramiro
Fonte: IARIA Publicador: IARIA
Tipo: Conferência ou Objeto de Conferência
Português
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This paper investigates the potential interactions between reader and tag anti-collision algorithms of passive RFID (radio frequency identification) systems. Conventionally, reader and tag anti-collision algorithms are designed by assuming that they are independent from each other. In practice, however, readers and tags usually operate in the same frequency band. Therefore, contention between their transmissions can also potentially arise. Furthermore, reader anti-collision policies directly influence the way in which tags are activated, and thus also the way in which they collide when responding to reader’s requests. In view of this and considering the growing numbers of readers and tags, independence of both schemes can not longer be considered as a realistic assumption. This paper partially fills this gap by proposing a new cross-layer framework for the joint evaluation and optimization of reader and tag anticollision algorithms. Furthermore, the paper proposes a new approach, based on a Markov model, which allows capacity and stability analysis of asymmetrical RFID systems (i.e., when readers and tags experience different channel and queuing states). The model captures the dynamics of tag activation and tag detection processes of RFID. It also represents a first step towards a joint design of physical (PHY) and medium access control layers (MAC) of RFID. The results indicate that the proposed approach provides benefits in terms of stability and capacity over conventional solutions even when readers and tags operate in different channels. The results also provide useful guidelines towards the cross-layer design of future RFID platforms.

Possibility of collision between co-orbital asteroids and the Earth

Domingos,R. C.; Winter,O. C.
Fonte: Sociedade Brasileira de Matemática Aplicada e Computacional Publicador: Sociedade Brasileira de Matemática Aplicada e Computacional
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2005 Português
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Considering hypothetical co-orbital asteroids with the Earth, Tatum (1997) presented a study about the necessary radial distance in order to produce collision. He adopted an analysis considering a composition of circular two-body systems, Sun-Earth and Sun-Asteroid. He found that asteroids with radial positions between 0.9943 and 1.0057 AU would necessarily collide with the Earth. In the present work, we show that this problem cannot be treated in this way. Adopting the circular restricted three-body problem, we verified that asteroids in the supposed region of collision with the Earth have stable horseshoe trajectories. Therefore, in the co-orbital region the dynamical system has to be studied as a restricted three-body problem since the composition of two-body problems gives a misleading result.

Report on the collision between a spinner dolphin and a boat in the Fernando de Noronha Archipelago, Western Equatorial Atlantic, Brazil

Camargo,Fernanda Scarano; Bellini,Claudio
Fonte: Instituto Virtual da Biodiversidade | BIOTA - FAPESP Publicador: Instituto Virtual da Biodiversidade | BIOTA - FAPESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2007 Português
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This paper reports a case of collision between an individual spinner dolphin and a boat in the Fernando de Noronha Archipelago, as an example of disturbance potentially caused by tourism industry activities. Photos illustrating the inflicted injuries on the animal are presented, and preventive measures to avoid this kind of accidents are proposed. This is the first report on a collision between spinner dolphins and boats.

Collision frequencies in the D-region

Vuthaluru, R.; Vincent, R.; Holdsworth, D.; Reid, I.
Fonte: Pergamon-Elsevier Science Ltd Publicador: Pergamon-Elsevier Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2002 Português
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Partial reflection differential absorption and differential phase observations have been used to systematically study collision frequencies (ν) in D-region of the lower ionosphere. The observations made with the large MF radar located at Buckland Park (35°S, 138°E) near Adelaide in the period September 1996–December 2000 show ν values larger than predicted by previously used models. The new estimates are compared with values calculated using new collision frequency momentum cross-sections for N₂(σ) measured in the laboratory. The two types of measurements are found to be in good agreement, with a moderate seasonal variation of ν at a constant height. No change due to solar cycle variations is found.; http://www.elsevier.com/wps/find/journaldescription.cws_home/211/description#description; R. Vuthaluru, R. A. Vincent, D. A. Holdsworth and I. M. Reid

Subducted upper and lower continental crust contributes to magmatism in the collision sector of the Sunda-Banda arc, Indonesia

Elburg, M.; van Bergen, M.; Foden, J.
Fonte: Geological Soc America Inc Publicador: Geological Soc America Inc
Tipo: Artigo de Revista Científica
Publicado em //2004 Português
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Pb isotopes in igneous rocks from the Banda-Sunda arc show extreme along-arc variations, which correspond to major lithologic changes in crustal components entering the subduction system. An increase in 206Pb/204Pb ratios toward the zone of collision with the Australian continent reflects input of subducted upper-crustal material; maximum values coincide with anomalously radiogenic 3He/4He ratios that have been earlier attributed to the involvement of the continental margin. The collision zone is further characterized by 208Pb/204Pb ratios that are higher for a given 207Pb/204Pb value than observed in the noncollisional sectors, and in the central part of the collision zone, the 206Pb/204Pb ratios are lower than the most radiogenic values in the adjacent areas. We propose that these Pb isotope signatures reflect input of subducted lower crust, mobilized as a result of slab-window formation during arc-continent collision. Variations in Pb isotopes in the collision zone are solely determined by variations in the nature and proportions of different subducted components. The Pb isotope arrays in the noncollision area may be dominated by slab components as well and could reflect mixing between subducted oceanic crust and entrained sediments...

New expression for collision efficiency of spherical nanoparticles in Brownian coagulation

Chen, Z.L.; You, Z.
Fonte: Shanghai Univ Publicador: Shanghai Univ
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
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The collision efficiency of dioctyl phthalate nanoparticles in Brownian coagulation has been studied. A set of collision equations is solved numerically to find the relationship between the collision efficiency and the particle radius varying in the range of 50 nm to 500 nm in the presence of Stokes resistance, lubrication force, van der Waals force, and elastic deformation force. The calculated results are in agreement with the experimental data qualitatively. The results show that the collision efficiency decreases with the increase of the particle radii from 50 nm to 500 nm. Based on the numerical data, a new expression for collision efficiency is presented.; Zhong-li Chen and Zhen-jiang You

Improved Collision Detection and Response Techniques for Cloth Animation

Mezger, Johannes; Kimmerle, Stefan; Etzmuß, Olaf
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Report (Bericht)
Português
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In the animation of deformable objects, collision detection and response are crucial for the performance. Contrary to volumetric bodies, the accuracy requirements for the collision treatment of textiles are particularly strict because any overlapping is visible. Therefore, we apply methods specifically designed for deformable surfaces that speed up the collision detection. In this paper the efficiency of bounding volume hierarchies is improved by adapted techniques for building and traversing these hierarchies. An extended set of heuristics is described that allows to prune the hierarchy. Oriented inflation of bounding volumes enables us to detect proximities with a minimum of extra cost. Eventually, the distance of the mesh faces is computed accurately, and constraints respond to the collisions.

Collision detection and post-processing for physical cloth simulation; Kollisionsdetektion und Nachbearbeitung bei der physikalischen Textilsimulation

Kimmerle, Stefan
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
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Um deformierbare Materialien wie Textilien oder menschliches Gewebe physikalisch simulieren zu können, muss eine Reihe komplexer Probleme gelöst werden. Diese Arbeit befasst sich dabei im Speziellen mit der Detektion und Behandlung von auftretenden Kollisionen sowie der Nachbearbeitung simulierter Netze zur Steigerung der visuellen Qualität. Dabei werden Anwendungen aus dem Bereich simulierter Textilien und der virtuellen Anprobe von Kleidung vorgestellt. Insbesondere wird auf das am WSI/GRIS entwickelte Textilsimulationssystem TüTex eingegangen. Zunächst wird der State of the Art zur Kollisionsdetektion deformierbarer Objekte vorgestellt, und es wird ausführlich diskutiert, welches Verfahren am besten für welche Anwendung geeignet ist. Für die Anforderungen, die TüTex an die Kollisionsdetektion stellt, wird gezeigt, dass sich dafür besonders Bounding-Volume-Hierarchien eignen. Diese werden im Weiteren mit einem stochastischen Sampling zu einer neuen Kollisionsdetektionsmethode kombiniert. Dieses neue Verfahren erlaubt eine Abwägung zwischen Geschwindigkeit und Qualität der Detektion und erhöht damit auch deutlich ihre Performance. Im Folgenden wird eine Impuls-basierte Methode zur Auflösung komplexer Kollisionen und Selbstkollisionen vorgestellt...

Case report, esophageal collision tumor (oat cell carcinoma and adenocarcinoma) in Barrett´s esophagus: immunohistochemical, electron microscopy and LOH analysis

González, L.M.; Sanz Esponera, J.; Saez, C.; Alvarez, T.; Sierra, E.; Sanz Ortega, J.
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
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We report a case of an esophageal collision tumor composed of adenocarcinoma and oat cell carcinoma. Both tumors appeared to arise from dysplastic Barrett's mucosae in a 75-year-old man. Immunohistochemical stains and electron microscopy demonstrated a separate identity for each of the tumors in collision. Molecular analysis of microsatellite regions was performed in different microdissected areas. Identical loss of heterozygosity (LOH) at 9p21 and 17p13 was determined in the three different microdissected areas of the adenocarcinoma component. LOH was not determined in any area of the oat cell carcinoma. This is the first study that analyzes the allele status of an esophageal collision tumor. Our findings suggest a biclonal origin for both components of the collision tumor.

Collision-free prioritized medium access control in wireless networks with hidden nodes

Andersson, Björn; Pereira, Nuno; Tovar, Eduardo
Fonte: IPP Hurray! Research Group Publicador: IPP Hurray! Research Group
Tipo: Relatório
Publicado em //2006 Português
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We propose a collision-free medium access control (MAC) protocol, which implements static-priority scheduling and works in the presence of hidden nodes. The MAC protocol allows multiple masters and is fully distributed; it is an adaptation to a wireless channel of the dominance protocol used in the CAN bus. But unlike that protocol, our protocol does not require a node having the ability to sense the channel while transmitting to the channel. Our protocol is collision-free even in the presence of hidden nodes and it achieves this without synchronized clocks or out-of-band busy tones. In addition, the protocol is designed to ensure that many non-interfering nodes can transmit in parallel and it functions for both broadcast and unicast transmissions.

Gondwanide continental collision and the origin of Patagonia

Pankhurst, Robert J; Rapela, Carlos W; Fanning, Christopher; Marquez, M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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A review of the post-Cambrian igneous, structural and metamorphic history of Patagonia, largely revealed by a five-year programme of U-Pb zircon dating (32 samples), geochemical and isotope analysis, results in a new Late Palaeozoic collision model as the

Spinel granulite in Odesan area, South Korea: Tectonic implications for the collision between the North and South China blocks

Oh, Chang Whan; Kim, Sung Won; Williams, Ian
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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Spinel granulite formed in the Fe-Al-rich layers in migmatitic gneiss adjacent to a late Paleozoic collision-related mangerite intrusion in the Odesan area, eastern Gyeonggi Massif, South Korea, contains the high-temperature (HT) assemblage Crd + Spl + Cr

Game Theoretic Modelling of a Human Driver?s Steering Interaction with Vehicle Active Steering Collision Avoidance System

Na, Xiaoxiang; Cole, David J.
Fonte: IEEE Publicador: IEEE
Tipo: Article; accepted version
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This is the accepted manuscript. The final version is available from IEEE at http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6951458&refinements%3D4262294079%26sortType%3Dasc_p_Sequence%26filter%3DAND%28p_IS_Number%3A7008592%29.; Development of vehicle active steering collision avoidance systems calls for mathematical models capable of predicting a human driver?s response so as to reduce the cost involved in field tests whilst accelerate product development. This article provides a discussion on the paradigms that may be used for modelling a driver?s steering interaction with vehicle collision avoidance control in path-following scenarios. Four paradigms, namely decentralized, noncooperative Nash, noncooperative Stackelberg and cooperative Pareto are established. The decentralized paradigm, developed based on optimal control theory, represents a driver?s interaction with the collision avoidance controllers that disregard driver steering control. The noncooperative Nash and Stackelberg paradigms are used for predicting a driver?s steering behaviour in response to the collision avoidance control that actively compensates for driver steering action. These two are devised based on the principles of equilibria in noncooperative game theory. The cooperative Pareto paradigm is derived from cooperative game theory to model a driver?s interaction with the collision avoidance systems that take into account the driver?s target path. The driver and the collision avoidance controllers? optimization problems and their resulting steering strategies arise in each paradigm are delineated. Two mathematical approaches applicable to these optimization problems...

Development of deterministic collision-avoidance algorithms for routing automated guided vehicles

Pai, Arun S.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
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A manufacturing job spends a small portion of its total flow time being processed on machines, and during the remaining time, either it is in a queue or being transported from one work center to another. In a fully automated material-handling environment, automated guided vehicles (AGV) perform the function of transporting the jobs between workstations, and high operational costs are involved in these material-handling activities. Consequently, the AGV route schedule dictates subsequent work-center scheduling. For an AGV job transportation schedule to be effective, the issue of collisions amongst AGV during travel needs to be addressed. Such collisions cause stalemate situations that potentially disrupt the flow of materials in the job shop, adding to the non-value time of job processing, and thus, increase the material handling and inventory holding costs. The current research goal was to develop a methodology that could effectively and efficiently derive optimal AGV routes for a given set of transportation requests, considering the issue of collisions amongst AGV during travel. As part of the solution approach in the proposed work, an integer linear program was formulated in Phase I with the capability of optimally predicting the AGV routes for a deterministic set of transportation requests. Collision avoidance constraints were developed in this model. The model was programmed using OPL / Visual Basic...