• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.3B
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• pp.248-253
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• 2011

Collision avoidance algorithm of vessels have been studied to avoid collision and grounding of a vessel due to human error. In this paper, We propose a collision avoidance algorithm using bayesian estimation theory for safety sailing and reduced risk of collision accident. We calculate collision risk for efficient collision avoidance using bayesian algorithm and determined the safest and most effective collision risk is predicted by using re-planned with re-evaluated collision risk in the future(t=t'). Others ship position is assumed to be informed from AIS. Experimental results show that we estimate the safest and most effective collision risk.

• Korean Journal of Psychosomatic Medicine
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• v.15 no.2
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• pp.107-112
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• 2007

Introduction : A positive thinking has been known to affect the enhancement of performance. One of temperament characters, harm avoidance is thought to be associated with anxiety related behaviors. Golfer showed highest anxiety and lowest score of harm avoidance, compared to any other sports. We hypothesized that positive feedback and reinforcement in golfer would decrease the anxiety and improve the performance. Methods : Fifty one golfers with the age from 15 to 19 were classified into two groups; 25 golfers who used Zinsser's Changing Negative thoughts to Positive thoughts and Beswick's positive self talk when exercise and competition (P-FB) and 26 golfers who had not (controls). Harm avoidance, Spielberg's Trait and State Anxiety, and Golf scores has been assessed at baseline and 6 months later. Results : There was no significant difference in baseline harm avoidance, anxiety, and golf scores between P-FB and controls. The total golf scores in both groups have improved after 6 month later. However, P-FB group showed greater improvement of total scores and putting scores, compared to controls. The state anxiety in PFB group has been decreased, while there was no change in controls. The change in the state anxiety was correlated with harm avoidance and the change in total golf scores. Discussions : The positive thinking has enhanced performance and state anxiety. The improvement of performance and anxiety in golfers was associated with high harm avoidance. The current study showed that the regulation of anxiety with positive thinking was helpful to the performance enhancement in subject with high harm avoidance.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1503-1510
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• 2012

This paper presents an Integrated Risk Management System (IRMS), which is designed to integrate longitudinal and lateral collision avoidance systems. Indices representing longitudinal and lateral collision risks are designed. From the designed indices, an integrated control strategy is designed. A collision avoidance algorithm is designed to assist the driver in avoiding collisions by using a vehicle-driver-controller integrated linear model. The performance of the proposed algorithm is investigated via computer simulations conducted using the vehicle dynamics software CARSIM and Matlab/Simulink.

• The Journal of Fisheries Business Administration
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• v.32 no.1
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• pp.41-55
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• 2001

본 논문의 목적은 김 양식 있어서 무기산 또는 유기산 사용 문제와 김 양식 어업인들의 생산위험 회피행위를 고찰하기 위한 이론적 틀을 개발하고, 정책함의를 도출하는데 있다. 김 양식의 생산위험 또는 가격위험은 김 양식 어업인들이 직면하고 있는 가장 중요한 의 사길정변수라고 할 수 있으며, 특히 문제가 되고 있는 무기산(또는 폐염산) 또는 유기산은 농업에 있어서 농약처럼 김 양식 어업인들이 생산위험을 최소화하기 위한 일종의 보험 생산요소(insurance production inputs)으로 볼 수 있다. 김 양식 어업인들의 생산위험은 평균(1차 적률 mean), 분산(2차 적률 variance), 왜곡도(3차 적률 skewnesss)에 의해 측정될 수 있으며, 특히 김 양식 어업인들은 확률이 낮을지라도 일단 첫병과 잡태(예: 파래 등)가 광범위하고 심각하게 발생하게 되면 생산물의 심각한 질적 저하가 야기된다는 사실을 경험적으로 인식하고 있다. 따라서 김 양식 어업인들은 평균생산 뿐만 아니라 생산의 분산과 하향성 확률 분포를 최소화할 수 있는 생산기술을 이용하게 된다. 이러한 김 양식 어업인들의 위험회피행위를 분석하기 위해 기대효용이론을 채택하고, 미지의 진효용함수를 테일러 시리즈 확장에 의해 3차 적률까지를 근사치로 이용하였다. 이윤에 대한 기대효용 극대화를 위한 1차 최적조건을 구하면, 어떤 산(무기산 또는 유기산)을 얼마만큼 이용하느냐 하는 문제는 생산량의 분산과 하향성 분포에 대한 김 양식 어업인들의 위험회피계수의 크기와 생산요소의 탄성치에 의해 결정된다. 특히 하향성 위험회피계수가 높고 3차 적률에 대한 생산요소 산의 탄성치가 클 경우 김 양식 어업인들른 하향성 위험을 줄이기 위해 상대적으로 강력하고 가격이 저렴한 산을 더 많이 이용하게 된다. 또한 두 가지 산의 효과가 같다면 무기산/유기산의 시장가격과 정부 산 가격 정책이 김 양식 어업인들의 산 종류 선택과 사용량 결정에 유의한 영향을 미치게 될 것이다. 무기산의 사용이 광범위하고 집약적으로 이루어질 경우 김 양식부문에서 폐공업용 염산 이용에 의한 생산위험 감소는 해양생태환경 파괴위험 증가로 이어질 수 있으며 여기에 바로 정부 산정책의 딜레마가 있다. 따라서 김 양식의 생산성 증대와 환경보전의 균형 유지에 대한 확고한 정책목표가 필요하며, 이러한 정책목표가 흔들릴 경우 산 문제에 대한 정부정책은 생산성 증대와 환경보전 어느 한쪽 부문에 심각한 왜곡현상을 초래할 수 있다.

• Journal of the Korean Institute of Intelligent Systems
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• v.27 no.2
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• pp.113-118
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• 2017

Various studies on the method of ship collision risk assessment for alarm have been reported constantly, and the result of the studies is applied to navigation devices. However, it is known that navigators ignore or turn off frequent alarms from the devices of predicting collision risk, because they may avoid collisions in the most of situations. In oder to make the prediction of ship collision risk more useful, it is necessary to consider the customary actions of ship collision avoidance. This paper proposes a system of analyzing collision avoidance measures of ships according to the types of encounter and managing the avoidance history of each ship. The core module of the system is designed as a neuro-fuzzy based inference system, and the test of the module validates the proposed system.

• Korean small business review
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• v.39 no.2
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• pp.89-107
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• 2017

This study investigates the effect of risk avoiding activities and characteristic of venture capital on the financial performance of invested companies. Based on the review on the literature, we present staged financing, syndicated investment and preferred stock investment as the measurements for risk avoiding activities. Types and age of venture capital were chosen as the variables for characteristic. The financial performance data of the invested companies was derived from their publicly announced yearly financial report. Data were analysed using logistic regression technique. The result show that syndicated investment and independent venture capital have positive influence on the growth of sales revenue and asset of the invested companies. Age of venture capital appears to be positively associated with growth of sales revenue. Staged financing and preferred stock investment, however, have no impact on any financial growth and profitability. Activities and characteristic of venture capital show no influence on the profitability.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.171-179
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• 2013

The primary function of navigation system is to provide route search and road guidance for safe driving for drivers. However, the existing route search system provides a simple service that looks up the shortest route using a safe driving DB without considering different road characteristics for the safety of the drivers. In order to maintain the safe driving, rather than searching the shortest path, a navigation system, in which the danger areas and/or the dangerous time zones have been considered, is required. Therefore, in this paper we propose a strategy of searching a navigation path to avoid danger areas for safe driving by using the A* algorithm. In the strategy, when evaluating the path-specific fitness of the navigation nodes, different heuristic weights were assigned to different types of risk areas. In particular, we considered three kinds of danger areas, such as accident-prone sections where accidents occur frequently, school zones, and intersection regions, as well as the time slots when the probability of danger is high. From computer simulation, the results demonstrate that the proposed scheme can provide the way to avoid danger areas on the route searching and confirm the possibility of providing the actual service.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.319-320
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• 2022

본 논문에서는 '지능형 해상교통정보 서비스'로 축적된 선박 위치데이터를 가공하여 선박의 조우상황 데이터를 추출하고 분석하였다. 선박의 위치, 침로, 속력을 통해 TCPA, DCPA와 선박간 거리를 계산함으로써 선박의 충돌위험 인지 후 회피 상황에서 보이는 데이터의 형태와 분포를 분석하였다. 추후 상대방위와 SOG가 TCPA 변화량에 미치는 영향에 대한 연구가 진행되면, 실제 사용자의 충돌위험 판단과 근접한 충돌위험도 분석 모델로 활용할 수 있을 것으로 보인다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.195-196
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• 2019

Studied for multiple obstacle avoidance algorithm based on COLREG for autonomous navigation vessel's safety navigation. By used VECTOR value of external obstacle provided by RADAR, CPA and TCPA of each obstacle are analyzed, and the obstacle is classified based on the value, the risk level is calculated considering multiple obstacle avoidance situations, and the avoidance action is applied to secure minimum safety situation.

• Journal of Navigation and Port Research
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• v.26 no.1
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• pp.8-14
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• 2002

The collisions of vessel at sea show high among the whole marine accidents. Especially, the accidents of fishing vessels take the largest portion of the collisions. Therefore, a technique to reduce these accidents should be developed. The automatic control for avoiding collision suggested in this study consists of two steps. The first is recognizing collision risk with fuzzy Theory and the other is maneuvering the model ship on the basis of collision risk calculated from the first step. The information form the position and estimated time of collision point(DCPA and TCPA) is used to assess the collision risk. To verify this system, a fishing vessel was simulated according to MMG mathematical model. The simulations result shows quite good application in avoiding the collision of ship.