• Spatial Information Research
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• 제18권3호
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• pp.73-83
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• 2010

본 연구는 정지장면의 연속영상간 각 픽셀위치에서 일어나는 통계적 특성을 활용하여 영상을 분할하는 기법을 제안한다. 공간정보의 획득과 분석에서 디지털 영상 처리 기법의 활용은 아주 중요한 의미를 가진다. 특히 디지털 영상의 영역 구분을 위해 다양한 영상 분할(image segmentation) 기법들이 활용되고 있다. 본 연구에서는 선행 연구한 연속프레임 영상의 분광학적 특성 분석의 결과를 바탕으로 연속 프레임 간 Randomness를 활용한 이미지 분할 방법을 제안하였다. 우선 연속 프레임 간 각 화소에 통계학적인 분석 방법을 적용하여 각 화소의 평균과 표준편차 값을 구하고, 이를 통하여 대상 영상에서 가장 신뢰할 만한 화소들을 찾아 씨앗 점(seed point)을 결정하였다. 그리고 이 씨앗 점들을 시작으로 이웃 화소 간 T-test를 실시하였으며, 이를 기반으로 영역 성장(region growing)의 개념을 적용하여 영상을 분할 할 수 있는 기법을 연구하였다. 제안방식의 성능을 검증하기 위하여 실험을 통하여 기존의 방식과 비교분석을 수행하였다. 이러한 실험의 결과 영상분할에서 영상의 단일 프레임을 활용한 것보다 연속 프레임을 활용한 경우가 유리함을 확인 할 수 있었다.

• 항공우주정책ㆍ법학회지
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• 제1권
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• pp.125-146
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• 1989

This paper is examine the problems of U.S.-Korea Air Service Agreement and recommend some directions for its improvement under the rapidly changing circumstance and growing importance of Korean penisula. Since the provisional agreement of 1949, U.S. -Korea Air Service Agreement has consistently been favorable to U.S. side. Fair and equal opportunity is the principle and basis of the bilateral air agreement. Notwithstanding such principle, it is only the U.S. carriers who can freely enter into any market, under the discretion of business strategy, while Korean carrier can serve only three points including Honolulu. In an effort to recitify such serious imbalance, Korea continuousely requested additional rights and has given utmost efforts to accommodate requests made by U.S. carries without much success. When we review aviation market between Korea and U.S. under the present agreement, Korea is fully open to U.S. carries as they can connect from any or all points in the U.S. via any or all points in Korea and all points beyond Korea. Increased number of U.S. carriers are enjoying greater utilization of the opportunity accorded them. Four(4) U.S. carries now operate to Korea using thirteen(13) gateway points and about one hundred fifty(150) on-line points in the U.S. such imbalance can be well understood when we review the exchange of traffic rights between the U.S. and the Pacific rim countries. During the yeras following the 1978 agreement with Korea, the U.S. proceeded to sign liberal agreements with Thailand, Taiwan, Singapore and the Phillipines. In exchange, the U.S. granted the four Pacific rim countries substantially greater rights than were granted to Korea, although Korea was the first Asian nation to sign a pro-competitive aviation agreement which granted U.S. carriers unrestricted market access and pricing flexibility. Moreover, Korea ranks the 2nd trading and tourist partner to the U.S. among the Pacific rim countries (Japan is the largest partner to the U.S. in terms of both trade and tourist market). In this paper such problems in the Korea-U.S. Air Services Agreement are analyzed in terms of historical perspective, U.S. Aviation policy, imbalance status in detail cases, discrimination to Korea comparing to other Asian countries, and theoretical application. And further it discusses current aviation issues between Korea and U.S. such as the ratification of 1980 MOU and various doing business issues of U.S. carriers in Korea. Finally, this paper concludes the analysis and suggests some directions to improve and rectify the problems and imbalance of U.S.-Korea Air Services Agreement in question.

• 한국측량학회지
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• 제35권2호
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• pp.75-80
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• 2017

Recently, there has been growing interest in spatial data that combines information and communication technology with smart cities. The high-precision LiDAR (Light Dectection and Ranging) equipment is mainly used to collect three-dimensional spatial data, and the acquired data is also used to model geographic features and to manage plant construction and cultural heritages which require precision. The LiDAR equipment can collect precise data, but also has limitations because they are expensive and take long time to collect data. On the other hand, in the field of computer vision, research is being conducted on the methods of acquiring image data and performing 3D reconstruction based on image data without expensive equipment. Thus, precise 3D spatial data can be constructed efficiently by collecting and processing image data using CCTVs which are installed as infrastructure facilities in smart cities. However, this method can have an accuracy problem compared to the existing equipment. In this study, experiments were conducted and the results were analyzed to increase the number of extracted matching points by applying the feature-based method and the area-based method in order to improve the precision of 3D spatial data built with image data acquired from stereo CCTVs. For techniques to extract matching points, SIFT algorithm and PATCH algorithm were used. If precise 3D reconstruction is possible using the image data from stereo CCTVs, it will be possible to collect 3D spatial data with low-cost equipment and to collect and build data in real time because image data can be easily acquired through the Web from smart-phones and drones.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.792-799
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• 2022

Building Information Modeling (BIM) technology is a key component of modern construction engineering and project management workflows. As-is BIM models that represent the spatial reality of a project site can offer crucial information to stakeholders for construction progress monitoring, error checking, and building maintenance purposes. Geometric methods for automatically converting raw scan data into BIM models (Scan-to-BIM) often fail to make use of higher-level semantic information in the data. Whereas, semantic segmentation methods only output labels at the point level without creating object level models that is necessary for BIM. To address these issues, this research proposes a hybrid semantic-geometric approach for clutter-resistant floorplan generation from laser-scanned building point clouds. The input point clouds are first pre-processed by normalizing the coordinate system and removing outliers. Then, a semantic segmentation network based on PointNet++ is used to label each point as ceiling, floor, wall, door, stair, and clutter. The clutter points are removed whereas the wall, door, and stair points are used for 2D floorplan generation. A region-growing segmentation algorithm paired with geometric reasoning rules is applied to group the points together into individual building elements. Finally, a 2-fold Random Sample Consensus (RANSAC) algorithm is applied to parameterize the building elements into 2D lines which are used to create the output floorplan. The proposed method is evaluated using the metrics of precision, recall, Intersection-over-Union (IOU), Betti error, and warping error.

• Korean Journal of Acupuncture
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• 제26권2호
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• pp.15-25
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• 2009

Objective: This paper aimed to understand influences on EEG conducting acupuncture stimulation, by comparing the changes in the acupoints on the body before and after normal people are treated with acupuncture at PC9 and TE3, which are referred to as Wood points(木穴), and PC5 and TE1, which are referred to as the Metal points(金穴) among the five shu points of Yin pericardium Meridian and Yang Triple Energizer Meridian. Methods: The study was performed on 30 healthy female volunteers in their 20's. EEG was measured for 5 minutes before acupuncture stimulation was conducted on PC9, TE3, PC5 and TE1. During 20 minutes of acupuncture treatment, the same items were continuously measured to find out whether there were any changes in them, and they were measured for 5 minutes after removing the acupuncture needles in order to implement a comparative analysis. Results: Comparision of EEG data before and after the treatment at PC9 shows no significant differences in all wave. Compared with the pre-acupuncture period at TE3, $\delta-\theta$ wave decreased significantly (P<0.05) during the acupuncture stimulation periods. Compared with the pre-acupuncture period at PC5, $\delta-\theta$ wave and high $\alpha$ wave increased significantly (P<0.05) during the acupuncture stimulation periods. And Mid $\beta$ wave and high $\beta$ wave decreased significantly (P<0.05) during the acupuncture periods and the post acupuncture periods. Compared with the Pre-acupuncture period at TE1, $\delta-\theta$ wave, $\theta$ wave and high $\alpha$ wave increased significantly (P<0.05) during the acupuncture stimulation periods. And Low $\beta$ wave decreased significantly (P<0.05) during the acupuncture periods. Conclusion: When acupuncture stimulation was performed on PC9 and TE3, referred to as the "Wood points", brain waves were stabled, while when acupuncture was performed on PC5 and TE1, called the "Metal points", a brain was waked. From the findings of this study, we hypothesize that the wood properties, from which growing starts in all things, are related with fast waves of EEG, and the metal properties, which stabilize and converge in all things, are related with slow waves of EEG.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.646-648
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• 2012

본 논문에서는 다양한 휴대단말 환경에서 획득한 영상에서 관심 객체의 특성을 추출하여 검출하는 내용 기반 영상 검색 기술을 제안한다. 검출하고자 하는 모델 영상의 HSI 컬러 정보를 이용한 컬러 히스토그램 정합법을 사용하여 관심 객체가 존재하는 템플릿을 검출한다. 해당 영역에서 해리스코너 검출 기법을 사용하여 코너 포인트를 검출 후 영역 성장법을 적용하여 관심 객체를 검출해내는 기법을 제안한다. 객체 검출 성능을 향상시키며 휴대단말 간의 속도를 향상시키기 위해 색상(Hue) 영역 정보만을 이용하여 연산량을 감소시키며 실시간 처리가 가능하도록 한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.107-110
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• 1996

Continuing advances in the formulation and solution of risk-sensitive control problems have reached a point at which this topic is becoming one of the more intriguing modern paradigms of feedback thought. Despite a prevailing atmosphere of close scrutiny of theoretical studies, the risk-sensitive body of knowledge is growing. Moreover, from the point of view of applications, the detailed properties of risk-sensitive design are only now beginning to be worked out. Accordingly, the time seems to be right for a survey of the historical underpinnings of the subject. This paper addresses the beginnings and the evolution, over the first quarter-century or so, and points out the close relationship of the topic with the notion of optimal cost cumulates, in particular the cost variance. It is to be expected that, in due course, some duality will appear between these notions and those in estimation and filtering. The purpose of this document is to help to lay a framework for that eventuality.

• 혜화의학회지
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• 제21권1호
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• pp.23-31
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• 2012

Allopathic medicine has had a lot of limits though it has maintained the status of mainstream medicine, therefore these days there has been a growing interests in traditional medicine of East Asia. According to this trend, the integration between allopathic medicine and traditional medicine has become a hot issue and the need of mutual understanding on their physiology and pathology increases. However, understanding of traditional medical theory based on ying-yang, five phases, viscera and bowels is still difficult to be accepted to allopathic medical fields. Therefore, this research tried to investigate the similarity and differences of the structures between five viscera and organs. As a result, this research found that the investigation and understanding on viscera in traditional medicine or organs in allopathic medicine has in common in some degree. However, the integration and comparison between two medicines should be done cautiously because there still are the basal different points of understanding of human structure and function.

• 한국압력기기공학회 논문집
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• 제7권2호
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• pp.21-25
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• 2011

Although many defects in PZR heater sleeve have been reported continually from operating experiences in oversea nuclear power plant, utilities get into difficulties in finding appropriate methods for diagnostics of the components due to the limited access or high radiation problems. Recently, as an alternative, diagnostics using Guided Wave Testing(GWT) are proposed and the attention of the methods has been growing gradually because of their long range inspection capability. This study is to investigate the effectiveness of GWT to detect PWSCC in welding points of PZR heater sleeve. Moreover, mode sensitivity analysis of GWT and optimal frequency for the diagnostics of PWSCC are presented by testing the mock-ups specimens that contain artificial flaws.

• 산업공학
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• 제17권3호
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• pp.314-329
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• 2004

The rapid growth of investments in mobile service to reach a large and growing body of customers, coupled with low communication costs, has made user acceptance an increasingly critical management issue. The study draws upon the task-technology fit (TTF) model as its theoretical basis and its empirical findings to pragmatically explain the key factors that affect the performance and user acceptance of mobile service in medical field. A total of 110 usable responses were obtained. The findings indicate that the task, technology, and individual user characteristics positively affect task-technology fit and mobile service usage. The task-technology fit and mobile service usage are the dominant factors that affect mobile service performance. The result points out the importance of the fit between technologies and users' tasks in achieving individual performance impact from mobile service in medical arena.