• 한국항해항만학회지
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• 제27권2호
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• pp.103-109
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• 2003

충돌위험도의 정량적인 평가는 항해 충돌방지 전문가 시스템 개발에 있어서 중요한 역할을 한다. 이 연구에서는 기존의 충돌위험도 평가 방법을 분석하여 문제점을 비교 검토하였으며, 그 대안으로 Sech 함수를 이용한 충돌위험도 평가 방법을 새롭게 시도하였다. 이를 충돌위험도 평가에 적용하고 본선의 안전한 행동구간을 결정할 수 있는 방법을 제시하였다.

• 한국항해항만학회지
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• 제27권4호
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• pp.351-357
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• 2003

충돌위험도의 정량적인 평가는 항해ㆍ충돌방지 전문가 시스템 개발에 있어서 중요한 역할을 한다. 이 연구에서는 sech 함수를 이용한 새로운 충돌위험도 평가법에서 나타난 기울기계수를 결정하는 방법을 이론적으로 분석하고 실제 상황에 적용할 수 있는 값을 제시하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.83-88
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• 2006

Evaluation of collision risk plays a key role in developing the expert system of navigation and collision avoidance. This paper presents a new collision risk model formula that is one modification model on the basis of one approach to the evaluation of collision risk using sech function produced by Prof. Jeong in his relevant $articles^{[2][3][4][5]}$. And as a grope in collision risk evaluation field, this paper applied the new model in appraising the collision risk, suggested how to decide the safe range of own ship’'s action. Moreover this paper also analyzed theoretically how to determine the coefficients as describes in the new modification model formula, and suggested the appropriate values as applicable.

• 한국항해항만학회지
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• 제31권2호
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• pp.121-126
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• 2007

Evaluation of collision risk plays a key role in developing the expert system of navigation and collision avoidance. This paper presents a new collision risk model formula that is one modification model on the basis of one approach to the evaluation of collision risk using sech function produced in earlier studies. And as a tool of the evaluation field of ship collision, this paper applied the new model in appraising the collision risk and represented how to decide the safe range of own ship's action. Moreover this paper also analyzed theoretically how to determine the coefficients as described in the new modification model, and suggested the appropriate values as applicable.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.57-60
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• 2004

충돌위험도의 정량적인 평가는 항해${\cdot}$충돌방지 전문가 시스템 개발에 있어서 중요한 역할을 한다. 이 연구에서는 sech 함수를 이용한 새로운 충돌위험도 평가법에서 피항구역의 문턱값을 결정하는 방법을 분석하고 실제 상황에 적용 가능한 식을 개발하였다.

• 한국항해항만학회지
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• 제27권6호
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• pp.619-624
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• 2003

Evaluating the risk of collision quantitatively plays a key role in developing the expert system of navigation and collision avoidance. This study analysed thoroughly how to determine the threshold function related to the avoidance time as described in the new evaluation of collision risk using sech function, and developed the appropriate equation as applicable.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.146-154
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• 2004

Evaluating the risk of collision quantitatively plays a key role in developing the expert system of navigation and collision avoidance. This study suggested and developed a new approach to the evaluation by using the sech function as an alternative to the existing methods of appraising the collision risk. This study also investigated and built up theoretically how to determine the gradient coefficients in this approach and suggested the appropriate values as much as applicable. Finally this study analyzed thoroughly how to determine the threshold function of avoiding time and developed the appropriate equation.

• 천문학논총
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• 제7권1호
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• pp.231-253
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• 1992

A model for the distribution of stars in the disk and the spheroid of our Galaxy is reexamined from an edge-on view of the Galaxy obtained by selecting infrared sources from the IRAS Point Source Catalog. The sources are counted as a function of galactic latitude. longitude and $12{\mu}m$ apparent magnitude. The source counts are reasonably separated into the disk component and the spheroid component contributions and each of the contributions is further interpreted as a convolution of a spatial density distribution and a luminosity function based on the least-square fit method. The spatial density of the disk component has an exponential radial scale length of $h_R{\sim}2.6\;kpc$ and the vertical distribution follows a canonical $sech^2$ law with a scale height $h_z{\sim}240\;pc$. The distribution of the spheroid component can be represented by an oblate spheriod with an axis ratio $k{\sim}0.61$ and a de Vaucouleurs' $r^{1/4}$ law with an effective radius of $R_e{\sim}120\;pc$. The steep density gradient of the spheroid component is consistent with that of late M giants in the central bulge. The luminosity functions of the disk and the spheroid component stars resemble respectively those of the K luminosity function of disk M giants (Garwood and Jones 1986) and the bolometric luminosity function of M giants in bulge fields (Frogel et al, 1990).