• 제목/요약/키워드: Risk Speed

검색결과 555건 처리시간 0.04초

Collision Risk Probability Considerations for Small Divided Areas

  • 국승기
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2013년도 추계학술대회
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    • pp.387-389
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    • 2013
  • In order to determine the collision risk, the probability estimation is very important part for accurate risk estimation. Recently, the collision risk at the Busan North Port is studied for making the risk map by authors. The result has been found some connections with previous collision places. For more precise estimation, the probability calculation is necessary. Recently the Bayesian matrix is mainly used for calculating the probabilities. Also considering the oil spill risk with tankers, ships' speed, relative angle and ships' size are key aspect whether breaking the double hull or not. This research presents the way of estimating the probabilities not her research and also the collision risk probability considerations for small divided areas.

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대용량 모빌리티 궤적 자료를 이용한 과속 위험노출도 분석 방법론 (Analysis Method for Speeding Risk Exposure using Mobility Trajectory Big Data)

  • 이숭봉;장현호;강태석
    • 한국재난정보학회 논문집
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    • 제17권3호
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    • pp.655-666
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    • 2021
  • 연구목적:본 연구는 대용량 차량궤적 자료를 이용하여 동적 과속 위험성을 측정하기 위한 방법론을 개발하고, 개발된 과속 지표의 적용성을 증명하는데 있다. 연구방법: 개별 차량 궤적을 이용하여 차량의 속도 변화를 미시적 시공간으로 분석하고, 사고 위험성 관점에서 과속의 경계(즉, 경계속도)를 결정하였다. 결정된 경계속도를 이용하여 미시적 시공간 기반 과속 노출도 지표를 개발하였다. 연구결과: 검증 연구는 대용량 차량 GPS 궤적 자료와 실제 교통사고 자료를 이용하여 수행되었다. 분석결과, 개발된 과속 노출도 지표는 고속도로 교통사고에 대해 우수한 설명력 (R2=0.7)을 보였다. 이는 미시적 시공간 차원에서 과속이 분석되어야 함을 직접적으로 의미한다. 결론:차량 속도 상태의 시공간적 변화는 매우 가변적이다. 따라서 본 연구에서 제시된 방법론은 차량 궤적 자료를 이용한 미시적인 공간기반 교통사고 요인 및 사고 위험 노출도 분석에 효과적으로 활용될 수 있을 것으로 판단된다.

Efficient navigation of mobile robot based on the robot's experience in human co-existing environment

  • Choi, Jae-Sik;Chung, Woo-Jin;Song, Jae-Bok
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2024-2029
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    • 2005
  • In this paper, it is shown how a mobile robot can navigate with high speed in dynamic real environment. In order to achieve high speed and safe navigation, a robot collects environmental information. A robot empirically memorizes locations of high risk due to the abrupt appearance of dynamic obstacles. After collecting sufficient data, a robot navigates in high speed in safe regions. This fact implies that the robot accumulates location dependent environmental information and the robot exploits its experiences in order to improve its navigation performance. This paper proposes a computational scheme how a robot can distinguish regions of high risk. Then, we focus on velocity control in order to achieve high speed navigation. The proposed scheme is experimentally tested in real office building. The experimental results clearly show that the proposed scheme is useful for improving a performance of autonomous navigation. Although the scope of this paper is limited to the velocity control in order to deal with unexpected obstacles, this paper points out a new direction towards the intelligent behavior control of autonomous robots based on the robot's experience.

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가려진 동적 장애물을 고려한 이동로봇의 안전한 주행기술개발 (Safe Navigation of a Mobile Robot Considering the Occluded Obstacles)

  • 김석규;정우진
    • 제어로봇시스템학회논문지
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    • 제14권2호
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    • pp.141-147
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    • 2008
  • In this paper, we present one approach to achieve safe navigation in indoor dynamic environment. So far, there have been various useful collision avoidance algorithms and path planning schemes. However, those algorithms have a fundamental limitation that the robot can avoid only "visible" obstacles. In real environment, it is not possible to detect all the dynamic obstacles around the robot. There exist a lot of "occluded" regions due to the limitation of field of view. In order to avoid possible collisions, it is desirable to consider visibility information. Then, a robot can reduce the speed or modify a path. This paper proposes a safe navigation scheme to reduce the risk of collision due to unexpected dynamic obstacles. The robot's motion is controlled according to a hybrid control scheme. The possibility of collision is dually reflected to a path planning and a speed control. The proposed scheme clearly indicates the structural procedure on how to model and to exploit the risk of navigation. The proposed scheme is experimentally tested in a real office building. The presented result shows that the robot moves along the safe path to obtain sufficient field of view, while appropriate speed control is carried out.

A Study on Risk Response against Ship Fire using Robot

  • Park, Dea-Woo;Park, Young-Suk;Nam, Jae-Min
    • Journal of information and communication convergence engineering
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    • 제9권2호
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    • pp.230-234
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    • 2011
  • It is endeavoring for sea safety and fire[1] at sea prevention solidifying control of standard technology and safety supervision aspect in IMO[2] but sea accident and ship fire are happening continuously. Because using Robot in artistic talent of ship in this treatise, studied that correspond to Risk and manage. Attach fire perception sensor for Robot's Risk confrontation, and because using infrared rays sensor, TOUCH SWITCH, sound perception sensor, gas perception sensor, light perception sensor that is threaded in Robot and is achieved, controlled Robot, and establish Low-High value the speed of sound output use and DC MOTOR and COM SEN of when indicate Risk confrontation to Robot and establish Robot's Risk confrontation administration action.

확률기반 비신호교차로의 우회전 전용차로 설치 기준 정립 (Establishing Probability-Based Warrants for Right-Turn Lanes at Unsignalized Intersections)

  • 문재필
    • 한국도로학회논문집
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    • 제19권6호
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    • pp.183-190
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    • 2017
  • PURPOSES : The objective of this study is to establish the traffic volume-based warrants of right-turn lanes at unsignalized intersections and to introduce a risk probability methodology based on the warrants. METHODS : In this study, a risk probability of a potential rear-end collision is applied between a right-turn vehicle and the immediately following through vehicle. Using the shifted negative exponential model and the compound probability theorem, the risk probability can be expressed as the function of directional volumes and the percentage of right-turns for a two-lane and four-lane highway, respectively. RESULTS : Based on the risk probablity, guidelines for installing right-turn lanes on two-lane and four-lane highways were developed. The risk probability also showed rationality by comparing with right-turn same-direction conflicts observed in-situ. CONCLUSIONS : The results of our study define the total approaching volumes to encourage a right-turn lane as a function of operating speed, percentage of right-turn, and number of lanes.

Contemplation of Risk Management for Internet Banking System

  • Seo, Jang-Hoon;Park, Myeong-Kyu
    • 대한안전경영과학회지
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    • 제5권2호
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    • pp.41-51
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    • 2003
  • Next Generation internet banking service for important role of banking business competitive power separates service function of individual banking and should equip various service that coincides in each special qualities these are customer management, portfolio management, global corporation support etc. The past few years have been characterized by rapid changes in technology and the introduction of corporate and retail banking services through the Internet. the integration of e-banking platforms with legacy systems and the increasing dependence of banks on third party information service providers, all dramatically amplify the magnitude of risks to which banks are exposed. Risk management disciplines have not evolved at the same speed and many institutions, especially the smaller ones, have not been able to incorporate Internet banking risk controls within their existing risk management structures. This article provides an overview of the various risks which are heightened with Internet banking, and a holistic approach to managing these risks. In addition, the presentation will explain the different risk areas and the controls to be adopted to mitigate these risks.

대기행렬이론을 이용한 병목지점 충돌위험 저감 가변속도제어 운영모형 (A Variable Speed Limits Operation Model to Minimize Confliction at a Bottleneck Section by Cumulative Demand-Capacity Analysis)

  • 이준형;손봉수
    • 대한교통학회지
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    • 제33권5호
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    • pp.478-487
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    • 2015
  • 본 연구에서는 검지기에서 수집가능한 교통정보를 이용한 대기행렬이론 기반 가변속도제어 운영모형과 그 효과를 제시하였다. 모형분석결과 가변속도제어를 실시할 때 총 지체가 3개 영역으로 나뉘어 발생하며, 총 통행시간의 증감없이 총 지체가 감소하였다. 이와 같은 가변속도제어 모형의 효과는 이론적 분석 후 VISSIM 미시 시뮬레이터를 통하여 검증하였으며, SSAM을 이용한 고위험 상충건수 분석이 이루어졌다. 분석결과 총 지체가 감소한 것으로 나타났으나, 총 통행시간이 동일하고 운전자의 희망통행속도는 가변속도제어 유무와 관계없이 동일하므로 실제 총 지체가 줄어든 것으로 볼 수 없다. 하지만 위 가변속도제어 모형은 자유속도 유지시간을 증가시키고, 속도편차발생 주기를 늘렸다. 이는 반복적인 지정체의 규모와 횟수 저감을 통해, 상하류부 교통류간 속도 차이를 줄여줌으로써 고위험 상충건수를 약 36.0% 저감하는 것으로 나타난다. 즉, 본 연구에서 제시한 가변속도제어값을 이용하여 가변속도제어를 실시할 경우 총 지체를 최소화함으로써 고위험 상충건수를 저감하는 안전성 향상효과를 기대할 수 있다.

고속 여객선의 교각 충돌에 대한 연구 (A Study on the Bow Collapse of High-Speed Passenger Craft in Collision with Bridge Pier)

  • 신영식;박명규
    • 해양환경안전학회지
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    • 제5권1호
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    • pp.1-8
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    • 1999
  • During the last 10 years, the various type of high speed craft have been greatly developed, and since around of 1990 the large size of high speed passenger and/or cargo vessels are also introduced and took into the service in the various routes over the world. In a marine traffic way some bridge need to build across a rivers, cannals or a waterways. This one will be an obstruction and potential risk of collision in the way of high speed craft. Accordingly some of collision accident have been reported, which were caused by a lost control, wind and hydrodynamic forces, fog or human errors. In this paper a high speed craft having 40 m length is assumed to be collided with a circular type of bridge piers at right angle. The mode of deformation, penetration depth of collapse, impact forces, reduction of speed, loss of kinetic energy, and influence of scantlings, etc. have been calculated in each speed with a time variation to find a maximum values within a limit, and are graphically presented.

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Use of Information Technologies to Explore Correlations between Climatic Factors and Spontaneous Intracerebral Hemorrhage in Different Age Groups

  • Ting, Hsien-Wei;Chan, Chien-Lung;Pan, Ren-Hao;Lai, Robert K.;Chien, Ting-Ying
    • Journal of Computing Science and Engineering
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    • 제11권4호
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    • pp.142-151
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    • 2017
  • Spontaneous intracerebral hemorrhage (sICH) has a high mortality rate. Research has demonstrated that sICH occurrence is related to weather conditions; therefore, this study used the decision tree method to explore the impact of climatic risk factors on sICH at different ages. The Taiwan National Health Insurance Research Database (NHIRD) and other open-access data were used in this study. The inclusion criterion was a first-attack sICH. The decision tree algorithm and random forest were implemented in R programming language. We defined a high risk of sICH as more than the average number of cases daily, and the younger, middle-aged and older groups were calculated as having 0.77, 2.26 and 2.60 cases per day, respectively. In total, 22,684 sICH cases were included in this study; 3,102 patients were younger (<44 years, younger group), 9,089 were middle-aged (45-64 years, middle group), and 10,457 were older (>65 years, older group). The risk of sICH in the younger group was not correlated with temperature, wind speed or humidity. The middle group had two decision nodes: a higher risk if the maximum temperature was >$19^{\circ}C$ (probability = 63.7%), and if the maximum temperature was <$19^{\circ}C$ in addition to a wind speed <2.788 (m/s) (probability = 60.9%). The older group had a higher risk if the average temperature was >$23.933^{\circ}C$ (probability = 60.7%). This study demonstrated that the sICH incidence in the younger patients was not significantly correlated with weather factors; that in the middle-aged sICH patients was highly-correlated with the apparent temperature; and that in the older sICH patients was highly-correlated with the mean ambient temperature. "Warm" cold ambient temperatures resulted in a higher risk of sICH, especially in the older patients.