• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2005년도 공동학술대회 논문집
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• pp.273-280
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• 2005

MT 전달함수의 추정과정에서 로버스트 방법의 적용은 현재 전자탐사 분야에서 일반적이다. 적절하게 고안되고 적용된 로버스트 방법은 출력 채널인 전기장에 포함되어 있는 외치의 영향을 감소시킬 수 있으나, HLP(High leverage point)라 불리 우는 자기장(입력 채널)의 외치에 종종 민감하지 못하다. 이 문제를 해결하기 위해 HLP의 영향을 최소화할 수 있는 BI(Bounded Influence) 추정이 제안되었고, 전통적인 로버스트 방법보다 신뢰성 있는 전달함수를 제공하는 것으로 보고되었다. 이는 BI 추정이 M-추정을 적용함과 동시에 자기장 성분만으로 결정되는 모자행렬의 통계적인 특성을 고려하여 가중치를 부여하는 방법이기 때문이다. 본 연구에서는 전달함수 추정과정에 BI 추정을 적용하고, 이와 더불어 전처리 단계로서 전자기장의 통계적 분포를 이용해 주파수 영역에서 극단적인 전기장과 자기장 자료의 영향을 감소시키는 기법을 개발하였다. 개발된 전처리 기법은 BI 추정으로 제거될 수 없는 자료를 주파수 영역에서 효과적으로 제거하는 것으로 생각된다. 본 연구에서 개발된 기법의 효율성과 장점은 합성 자료와 현장 자료를 이용하여 도시될 것이다.

• 통상정보연구
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• 제11권3호
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• pp.339-361
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• 2009

This paper attempts to provide a way to improvement in trade & commerce between Korea and Russia, analyzing the influence of the circumstances of the Russian economy on economic relations between the two countries. The study briefly reviews the current situation of the Russian economy, and tries to examine the strong points to be considered as leverage for cooperation and the weak points to be overcome. Previous studies have determined that the Russian economy has unlimited potential for growth, because it is endowed with abundant resources, and has a government willing to reform for the opening of the economy, as well as high-quality labor. However, the economic structure is vulnerable to impact of the worldwide financial crisis. It is not possible to overlook its institutional fragility and vulnerability such as a corrupt bureaucracy or a relatively large black market. These undesirable factors may not only undermine the basis of Russia economy but also a hindrance to economic cooperation by increasing economic uncertainty. This paper attempts to analyze comprehensively the socio-economic factors that influence the open-economy of Russia, and to illustrate strategies for improvement in trade and commerce through the viewpoint of Korean firms that are already in business or are trying to enter in the near future. Some measures to improve their economic cooperation are suggested at the end.

• International Commerce and Information Review
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• 제2권1호
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• pp.83-103
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• 2009

This paper attempts to provide a way to improvement in trade & commerce between Korea and Russia, analyzing the influence of the circumstances of the Russian economy on economic relations between the two countries. The study briefly reviews the current situation of the Russian economy, and tries to examine the strong points to be considered as leverage for cooperation and the weak points to be overcome. Previous studies have determined that the Russian economy has unlimited potential for growth, because it is endowed with abundant resources, and has a government willing to reform for the opening of the economy, as well as high-quality labor. However, the economic structure is vulnerable to impact of the worldwide financial crisis. It is not possible to overlook its institutional fragility and vulnerability such as a corrupt bureaucracy or a relatively large black market. These undesirable factors may not only undermine the basis of Russia economy but also a hindrance to economic cooperation by increasing economic uncertainty. This paper attempts to analyze comprehensively the socio-economic factors that influence the open-economy of Russia, and to illustrate strategies for improvement in trade and commerce through the viewpoint of Korean firms that are already in business or are trying to enter in the near future. Some measures to improve their economic cooperation are suggested at the end.

• 로봇학회논문지
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• 제16권3호
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• pp.189-198
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• 2021

In this paper, we introduce the software/hardware system that can reliably calculate the distance from sensor to the model regardless of point cloud density. As the 3d point cloud map is widely adopted for SLAM and computer vision, the accuracy of point cloud map is of great importance. However, the 3D point cloud map obtained from Lidar may reveal different point cloud density depending on the choice of sensor, measurement distance and the object shape. Currently, when measuring map accuracy, high reflective bands are used to generate specific points in point cloud map where distances are measured manually. This manual process is time and labor consuming being highly affected by Lidar sparsity level. To overcome these problems, this paper presents a hardware design that leverage high intensity point from three planar surface. Furthermore, by calculating distance from sensor to the device, we verified that the automated method is much faster than the manual procedure and robust to sparsity by testing with RGB-D camera and Lidar. As will be shown, the system performance is not limited to indoor environment by progressing the experiment using Lidar sensor at outdoor environment.

• 응용통계연구
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• 제20권3호
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• pp.551-559
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• 2007

로지스틱회귀에서 일반적으로 사용되는 최대우도추정법은 이상점에 대해 로버스트 하지 않다. 따라서 본 논문에서는 로지스틱회귀모형의 로버스트 추정을 위한 알고리즘을 제안하고자 한다. 이 알고리즘은 V-마스크 형태의 경계기준에 의해 나쁜 지렛점과 수직이상점을 식별하고, 식별 결과를 바탕으로 이상점의 영향력을 감소시키기 위한 효과적인 방안을 모색한다. 이상점의 영향력 감소는 가중치와 조정치를 적절히 선정함으로 가능하며, 그 결과 붕괴점이 높은 추정치를 얻게 된다. 제안된 알고리즘을 다양한 자료에 적용하여 정분류율을 측정하여 비교하였는데, 새로운 알고리즘이 최대우도추정보다 정확한 분류를 해 주는 것으로 평가되었다.