• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.89-94
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• 2004

선박운항시스템은 첨단화 되고 있으며, 선박충돌회피시스템에 관한 연구가 활발히 진행되고 있다. 그럼에도 선박 충돌사고 빈도수는 줄어들지 않는 설정이다. 시스템에 의한 충돌회피 조종에도 불구하고 근접거리로 충돌위험이 계속 존재한다면, 충돌위험 결정 및 판단기준에 있어서 단순히 TCPA, DCPA만의 입력변수 사용은 근접상황에서 충돌위험회피에 도움을 주지 못한다. 최근 5년간 국내 선박충돌사고 상대선 초인거리 조사에 의하면 약 $45\%$가 2마일 이하 근거리 초인하는 것으로 분석된다. 이런 요소는 선박조종성능 특성과 행위결정을 위한 시간적 특성의 영향을 많이 받는 근접조우를 유발한다. 따라서 근접상황에서 선박충돌회피동작 결정에 관한 연구는 안전항해의 필수적인 요소라고 할 수 있을 것이다. 본 논문에서는 선박조종성능 특성에 따른 선회조종과 선박의 거동을 분석하여 근접상황에서 신속하고 올바른 충돌회피 조선을 지원할 수 있는 선박충돌회피지원 모델을 제시한다.

• 한국해양공학회지
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• 제15권3호
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• pp.120-127
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• 2001

The potential pollution problems resulting from tanker collision necessitate the requirement for an effective structural design and the development of relevant safety regulations. During a few decades, the great effort has been made by the international Maritime Organization and the Administration, etc, to reduce oil spillage from collision accidents. However there is still a need for investigation in the light of structural evaluation method for the experiments and rational analysis, and design development for an operational purpose of ships. This study aims for investigating a complicated structural response of bow structures of simplified models and oil carriers for assessing the energy dissipation and crushing mechanics of the striking vessels through a methodology of the numerical analysis for the various models and its design changes. Through these study an optimal bow construction absorbing great portion of kinetic energy at the least penetration depth prior to reach to the cargo area and an effective location of collision bulkhead are investigated. In order to obtain a rational results in this study, three stages of collision simulation procedures have been performed step by step as follows; 1) 16 simplified ship models are used to investigate the structural response against bow collision with variation of primary and secondary members. Mass and speed are also varied in four conditions. 2) 21 models consisted of 5 sizes of the full scaled oil carriers are used to perform the collision simulation with the various sizes and deadweight delivered in a recent which are complied with SOLAS and MARPOL. 3) 36 models of 100l oil carrier are used to investigate the structural response and its influence to the collision bulkhead against bow collision in variation with location of collision bulkhead, primary members, framing system and colliding conditions, etc. By the first study using simplified models the response of the bow collision is synthetically evaluated for the parameters influencing to the absorbed energy, penetration depth and impact force, etc.

• 한국항해항만학회지
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• 제28권10호
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• pp.827-832
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• 2004

선박운항시스템은 첨단화 되고 있으며, 선박충돌회피시스템에 관한 연구가 활발히 진행되고 있다. 그럼에도 선박 충돌사고율은 줄어들지 않는 실정이다. 시스템에 의한 충돌회피 조종에도 불구하고 근접거리로 충돌위험이 계속 존재한다면, 충돌위험 결정 및 판단기준에 있어서 단순히 TCPA, DCPA만의 입력변수 사용은 근접상황에서 충돌위험회피에 도움을 주지 못한다. 최근 5년간 국내 선박충돌사고 상대선 초인거리 조사에 의하면 약 $45\%$가 2마일 이하 근거리 초인하는 것으로 분석된다. 이런 요소는 선박조종성능 특성과 행위결정을 위한 시간적 특성의 영향을 많이 받는 근접조우를 유발한다. 따라서 근접상황에서 선박충돌회피동작 결정에 관한 연구는 안전항해의 필수적인 요소라고 할 수 있을 것이다. 본 논문에서는 선박조종성능 특성에 따른 선회조종과 선박의 거동을 분석하여 근접상황에서 신속하고 올바른 층돌회피 조선을 지원할 수 있는 선박충돌회피지원 모델을 제시한다.

• 한국군사과학기술학회지
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• 제12권2호
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• pp.213-221
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• 2009

An aircraft collision accident is a disaster that causes great losses of inventories and lives. Though a collision avoidance warning function is provided automatically to pilots in the aircrafts by the enhancement of the aircraft capability, achieving fast decision-making to escape a collision situation is a complex and dangerous work for pilots. If an in-flight collision situation is controlled by the air traffic control system which monitors all airplanes in the air, it would be more efficient to prevent in-flight collisions because it can handle the emergency before the pilot's action. In this paper, we develop the collision avoidance warning function in the air traffic control system. Specifically, we design and implement the five stages of the collision avoidance function, and propose a visualization method which could effectively provide the operators with the trajectories and altitudes of the aircrafts in a collision situation. By developing an in-flight collision warning function in the air traffic control system that visualizes flight patterns through the state transition data of in-flight aircrafts on the flight path lines, it can effectively prevent in-flight collisions with traffic alerts. The developed function allows operators to effectively select and control the aircraft in a collision situation by providing the operators with the expected collision time, the relative distance, and the relative altitude while assessing the level of alert, and visualizing the alert information which includes the Attention-Warning-Alert phase via embodying the TCAS standard. With the developed function the air traffic control system could sense an in-flight collision situation before the pilot's decision-making moment.

• 한국산학기술학회논문지
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• 제22권2호
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• pp.514-521
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• 2021

수식적 해법을 이용하여 교차로 교통사고 충돌 속도를 산정을 위해서는 충돌 전 차량 진입각 및 충돌 후 차량 이탈각 추정은 비교적 쉽지만, 충돌 후 차량의 감속을 분석하기는 매우 어렵다. 충돌 지점부터 최종 위치까지 이동하는 과정에서 노면 흔적이 발생하지 않으면, 충돌 후 차량의 감속을 분석하기 어렵다. 차량의 주행 특성에 따른 관성력과 충돌 부위 및 충돌 속도에 따른 편심력 등의 작용으로 충돌 후 차량 운동 궤적은 불규칙한 곡선 궤적을 보인다. 그러므로, 정확한 충돌 속도 분석을 위해서는 충돌 후 적정한 이탈각을 설정하는 것이 매우 중요하다. 본 연구에서는 컴퓨터 시뮬레이션(PC-Crash)을 이용한 모의 충돌 실험 자료에 근거하여 충돌 후 적정한 차량 이탈각과 충돌 속도와의 상관관계를 분석하여 회귀 분석 모형을 제안하고, 교차로 충돌사고에 차량 이탈각만을 적용한 충돌 속도 산출 방법을 제시하였다. 본 연구의 회귀 분석 모형에서 결정 계수는 0.864이므로 제시한 회귀 분석 모형이 매우 적합하다는 것을 알 수 있다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.68-68
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• 2017

• 한국자동차공학회논문집
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• 제20권3호
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• pp.113-118
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• 2012

Collision detection plays a key role in collision mitigation system. The malfunction of the collision mitigation system can result in another dangerous situation or unexpected feeling to driver and passenger. To prevent this situation, the collision time, offset, and collision decision should be determined from the appropriate collision detection algorithm. This study focuses on a method to determine the time to collision (TTC) and frontal offset (FO) between the ego vehicle and the target object. The path prediction method using the ego vehicle information is proposed to improve the accuracy of TTC and FO. The path prediction method utilizes the ego vehicle motion data for better prediction performance. The proposed algorithm is developed based on laser scanner. The performance of the proposed detection algorithm is validated in simulations and experiments.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.559-564
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• 2008

A prediction of binary droplets collision is important in the formation of falling drops and the evolution of sprays. The droplet velocity, impact parameter and drop-size ratio have influence on the interaction of the droplets. By the effect of these parameter, the collision processes are generated with the complicated phenomena. The droplet collision can be classified into four interactions such as the bouncing, coalescence, reflexive separation and stretching separation. In this study, the two-phase flow of the droplet collision was simulated numerically by using the Level Set method. 2D axi-symmetric simulations on the head-on collisions in the coalescence and reflexive separation, and 3D simulation on the off-center collisions in the coalescence and stretching separation were performed. These numerical results showed good agreements with the experimental and analytical results. For tracking the identity of droplets after the collision, transport equation for the volume fraction of the each initial droplet were used. From this, the identities of droplets were analyzed on the collision of droplets having different size.

• 한국자동차공학회논문집
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• 제7권8호
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• pp.233-247
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• 1999

Traffic accidents are normally caused by late or faulty judgements due to the driver's inaccurate estimation of the distance, velocity, and acceleration from the surrounding vehicles as well as his carelessness or inattention. Thus, the development of collision avoidance systems is motivated by their great potential for increased vehicle safety. A typical collision avoidance system consists of the forward-looking sensor, the criteria for activation of collision warming and avoidance, the collision avoidance maneuvers, and the user interface. This thesis is concerned with the development of a collision warning algorithm in which the driver is warned of approaching collision with the visual and/or the audible signals . The warning algorithm based on fuzzy logic is presented here based on new warning criteria. It has been newly derived from the conventional warning equation by adding a new input variable of the required deceleration to avoid collision. The algorithm is also able to adapt to the individual driver's taste along with the different road conditions by externally controlling the warning intensity. Finally , the proposed algorithm has been validated using computer simulation.

• 로봇학회논문지
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• 제2권3호
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• pp.234-241
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• 2007

Effective tools which can alleviate the complexity and computational load problem in collision-free motion planning for multi-agent system have steadily been demanded in robotics field. To reduce the complexity, the extended collision map (ECM) which adopts decoupled approach and prioritization is already proposed. In ECM, the collision regions which represent the potential collision of robots are calculated using the computational power; the complexity problem is not resolved completely. In this paper, we propose a mathematical analysis of the extended collision map; as a result, we formulate the collision region as an equation with 5-8 variables. For mathematical analysis, we introduce realistic assumptions as follows; the path of each robot can be approximated to a straight line or an arc and every robot moves with uniform velocity or constant acceleration near the intersection between paths. Our result reduces the computational complexity in comparison with the previous result without losing optimality, because we use simple but exact equations of the collision regions. This result can be widely applicable to coordinated multi-agent motion planning.