• 한국도로학회논문집
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• 제16권1호
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• pp.91-98
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• 2014

PURPOSES : Recently, there are increasing bicycle accidents along with increasing bicycles users. Bicycle accidents occurred frequently by perpendicular collision form at intersection inner. In order to improve safety of bicycle, drivers need to be aware of bicycles on the road and intersection geometric designs need to be designed to reduce risk associated with collisions between bicycles and car. This study aims to review the location of bicycle crossing in the viewpoint of bicycle safety. METHODS : Four types of bicycle crossing by curve radius and driver's check around the behavior are set to simulate the risk of collisions between bicycles and car turning right. Simulation using fortran programming are conducted on total 60 cases. RESULTS : Bicycle crossing located behind of crosswalk is lower the risk of collisions with car in all cases. In addition to the larger curve radius of pavement edge at intersection and the more pay attention to the rear by the turn head to the right is too low the risk of collisions with car. CONCLUSIONS : It is show that the location of bicycle crossing is safer behind than in front of crosswalk in the viewpoint of bicycle safety.

• Ocean Systems Engineering
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• 제5권3호
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• pp.181-198
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• 2015

An OSV (Offshore Support Vessel) is being used to install a structure which is laid on its deck or an adjacent transport barge by lifting off the structure with its own crane, lifting in the air, crossing splash zone, deeply submerging, and lastly landing it. There are some major considerations during these operations. Especially, when lifting off the structure, if operating conditions such as ocean environmental loads and lifting off velocity are not suitable, the collision can be occurred due to the relative motion between the structure and the OSV or the transport barge. To solve this problem, this study performs the physics-based simulation of the lifting off step while the OSV installs the structure. The simulation includes the calculation of dynamic responses of the OSV and the structure, including the collision detection between the transport barge and the structure. To check the applicability of the physics-based simulation, it is applied to a problem of the lifting off step by varying the ocean environmental loads and the lifting off velocity. As a result, it is confirmed that the operability of the lifting off step are affected by the conditions.

• 한국정보통신학회논문지
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• 제13권9호
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• pp.1795-1802
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• 2009

웹캠을 사용한 체감형 기능성게임은 손과 팔 머리 등 온몸을 인터페이스로 사용하는 게임과 운동을 병행하는 새로운 형태의 게임이다. 이때 게이머의 움직임이 미치는 공간이 게임 정보공간으로 이 공간상에 가상객체와의 상호작용이 발생하는 곳이다. 이 공간을 효과적으로 분할, 분석하여 게이머의 공격으로부터 적 캐릭터가 효과적으로 피할 수 있는 방법을 제안한다. 본 논문에서는 게임 공간을 9등분하여 적 캐릭터의 위치와 상, 하, 좌, 우의 게이머의 움직임 정보를 이용하여 충돌 회피를 구현한다. 이를 검증하기 위하여 웹캠, 게임플레이어, 적 캐릭터로 구성된 체감형 기능성 게임을 제작하고, 제안한 기법을 사용하여 충돌 회피를 실험하여 그 타당성을 확인하였다. 특히 적 캐릭터 앞 공간 영역에 움직임 정보가 있는 경우 제자리 뛰기를 하면서 기다리며 충돌회피 공간을 찾음으로써 보다 재미있고, 효과적인 충돌회피가 가능하였다. 제안한 알고리즘은 웹캠을 이용한 체감형 기능성게임의 효과적인 상호작용과 레벨조정 등 개발 알고리즘으로 활용될 수 있다.

• 한국정보통신학회논문지
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• 제21권4호
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• pp.731-736
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• 2017

본 논문에서는 능동형 RFID 시스템의 표준인 ISO/IEC 18000-7의 성능을 개선하기 위하여 간소화된 태그 수집 알고리즘을 제안한다. 제안한 알고리즘에서는 태그 수집 라운드의 시작을 나타내는 수집 명령을 수정하여, 이전 라운드의 LP 구간 응답에 대한 결과를 포함시킨다. 수집 명령을 수신한 태그는 자신이 응답한 슬롯의 충돌 여부를 확인하고, 별도의 점대점 읽기 명령과 슬립 명령 없이 자신의 데이터 슬롯으로 추가적인 데이터를 전송하고 슬립 상태로 천이한다. 표준에서의 수집 라운드는 일련의 수집 명령, 수집 응답, 읽기 명령, 읽기 응답, 및 슬립 명령으로 구성된다. 반면, 제안한 태그 수집 알고리즘은 표준과는 달리 하나의 수집 라운드가 수집 명령 및 수집 응답으로만 구성된다. 성능 분석결과, 태그의 수가 300개일 때 제안한 기법의 평균 식별지연은 표준에 비하여 16% 개선됨을 알 수 있었다.

• 수산해양기술연구
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• 제52권3호
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• pp.232-240
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• 2016

Marine casualties originated from fishing vessels occupied about 71.2% of the whole marine casualties in Korea from 2008 to 2014, which has not changed much for a long time. Therefore, a pragmatic counterplan to decrease in casualties in fishing vessel is indispensable for reduction of marine casualties in Korea. Since the casualties occurred by fishing vessels may incline to a specific type of casualties according to the difference in the operating type; in this paper, 11 fishing types which occurred casualties frequently in numbers and occupied ratio were selected. Since the most frequent occurring casualties in fishing vessels were from collisions and fire explosion in statistics from KMST (2008~2014), the study focused on them. The collision is given a great deal of weight in all the casualties mostly due to the negligence of duty regardless of the job types. Gill netter, trap fishing boat, jig boat, multiple fishing boat and stow netter have their own specific causes of casualties in collision according to the operating types. The cause of fire explosion was mainly due to poor inspection and maintenance the electric cord. For this reason, it may be necessary for an operator to make strict precaution on the other vessels under way systematically, keep the regulation for preventing collisions, and for an engineer on watch to make a check the electricity periodically to reduce the fire explosion.

• 수산해양기술연구
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• 제49권1호
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• pp.29-39
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• 2013

Fishing vessels have been causing more than 70% of marine casualty in Korea. As a view of the occurring number of marine casualty, it is obvious for fishing vessel to account for the absolute high portion of that in comparison with the non-fishing vessels. That is a natural outcome because fishing vessels have occupied more than 90% of all registered Korean vessels. If we consider it not occurring number, but occurring ratio, we could find out that fishing vessels accounted for 5 times lower than non-fishing vessels in marine casualties. Nevertheless, fishing vessels have not immunity from responsibility for marine casualties at all, because the tendency of it in fishing vessel has been dominating the whole marine casualties in Korea. So for reduction of them, it is indispensable to decrease the casualties of fishing vessel. In this study, the authors tried to carry out many items of them to compare the occurring number with the occurring ratio, and dealt with the casualties of collision and machine damage in detail, because those have not only been occurring most frequently in casualties in Korea, but also led to the death and injury of lives. To reduce the collision and the machine damage, the operator have to keep the watch more strictly and check and keep the machine in good order. And it is necessary for the operator to take more education and training intended to decrease those systematically and continuously, especially for the crews of fishing vessels.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.402-408
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• 2021

기계 설계를 기반으로 제작한 자동차에 의한 사고 발생 시 차량 공학적인 분석은 심도 있게 조사하지 않고 조사자의 주관적인 경험 지식을 토대로 분석하는 경우가 있다. 본 연구는 실제 발생한 중앙선 침범 사고 자료를 토대로 캐드(CAD) 프로그램을 이용하여 현장 상황을 도면화하고, 도면화 한 자료를 시뮬레이션 프로그램(PC-Crash)에 적용하여 250번의 충돌 상황을 반복적으로 수행하여 최종 정지 위치 및 최종 정지 자세와 부합하는 충돌 속도, 진행 자세, 조향 작동 여부 및 제동 여부 등의 상관 관계를 분석했다. 충돌 속도가 낮을수록 이탈각의 영향을 크게 받지 않고 속도가 높은 차량의 속도에 영향을 크게 받고 충돌 이후에는 유효 충돌 속도와 같이 속도가 낮은 차량은 높아지고, 속도가 높은 차량은 낮아진다. 본 연구의 시뮬레이션 결과는 마이티가 중앙선을 넘은 자세로 오르막 좌커브 구간을 진행하다가 마주오던 포터를 인지하고 자기 진행 차로로 복귀하는 과정과 포터의 전면 좌측면이 충돌하여 포터가 우대각선 방향으로 밀려나 전면이 약 11시 방향을 향해 최종 정지하는 것을 규명하였다.

• 대한조선학회논문집
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• 제49권5호
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• pp.400-409
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• 2012

It is not easy to know the accurate mass and mass moment of inertia of robot. Because of this uncertainty, error may exist when we control the robot based on the inaccurate mass information. Moreover the properties of the portable robot can change during its operation. Therefore we developed the motion simulator based on the adaptive control. First, the computed torque control was carried out in order to minimize an error between target angles and real angles. The computed torque control is based on the equation of robot motion, which is derived from the Lagrange-Euler equation. To minimize the error between the real model and the approximated model, the adaptive control was carried out. During this simulation, the interference check was also carried out. The interference check verifies that the robot can move successfully without any collision.

• 대한기계학회논문집B
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• 제28권3호
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• pp.256-264
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• 2004

The granular flow has been numerically studied by using DEM(Discrete Element Method). The eve교 particle is checked if it collides neighbor particles, and the next motion of the particle is predicted. The computing time has been drastically reduced by improving the collision check against neighboring particles. The comparison of the present method with ail experiment for the vibrating floor problem shows the good accuracy. The broken tower problem has been calculated to show the good comparison with the other computational result. This DEM(Discrete Element Method) can be a useful tool for constructing the constitute equation of the continuum approach of the granular flow.

• 한국자동차공학회논문집
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• 제11권6호
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• pp.118-126
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• 2003

Digital Manufacturing is a technology facilitating effective developments and agile productions of the product via digital computer models representing physical and logical schema and the behavior of the real manufacturing systems including manufacturing resources, environments and products. For the successful application of this technology, a digital factory as a well-designed and an integrated environment is essential. In this paper, we constructed the sophisticated digital factory of a Korean automotive company's body shop, and conducted precise simulations of unit cell, lines and the whole factory for the collision check, the production flow analysis and the off-line programming. We expect that this digital factory of the body shop helps us achieve great savings in time and cost for many manufacturing preparation activities of the new car development.