• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.208-208
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• 2009

최근 광섬유 센서기술의 수요는 전 산업분야에 걸쳐 높아지고 있으며, 이에 비례하여 기업 간, 국가 간 경쟁이 첨예화되고 있다. 또한 소형화, 경량화, 고성능화 센서에 대한 요구도 높아지고 있어 종래의 각종 센서들의 형태와 개선을 위한 연구개발이 매우 활발하게 전개되고 있으므로 이를 대체할 수 있는 광섬유 센서의 수요가 급격히 늘어날 전망이다. 기존 침입자 감지 시스템은 태풍, 낙뢰, 폭설, 폭우 등의 기상변화나 지반 흔들림, 통행차량 진동 및 전자기 간섭 등에 영향을 받아 오작동, 오경보가 빈번히 발생된다. 이러한 문제의 해결책으로 광섬유 센서 케이블을 이용한 시스템이 대안으로 부각되고 있다. 현재 국내에서 군부대, 공항을 중심으로 펜스와 휴전선 철책에 힘입자 감지를 위하여 도입되고 있다. 광섬유 센서 케이블을 사용하는 광망경비시스템은 광섬유 센서 케이블을 그물망 형태(광망)로 만들어 경계 지역에 설치된다. 광망경비시스템의 원리는 광섬유에 광펄스를 입사시켜 순환시키는데 침입자가 광망을 절단하거나 외력을 가할 경우 발생되는 레일리 산란에 기인하는 후방산란과 접속점과 파단점에서 생기는 반사광을 OTDR(Optical Time Domain Reflectometer)로 검출하여 침입상황 및 침입위치를 탐지한다. 그러나 이러한 침입자 감지를 위한 광망경비시스템의 핵심부품인 광섬유 센서 케이블은 기존에 전량 해외수입에 의존하고 있는 실정이며, 지금까지 국내에서 생산하기 위한 제작 기술과 노하우가 초보단계에 머물러 있다. 이러한 광섬유 센서 케이블 제작에 있어서 중요한 부분이 패키징 기술이라 할 수 있다. 이는 광섬유 센서를 일반적인 피복 구조로 패키징하게 되면, 센서 고유의 특성이 패키징 과정과 운반과정, 포설과정에서 변하게 되고 센서로써의 신뢰성이 크게 저하된다. 본 연구에서는 힘입자 감지용 광섬유 센서 케이블의 설계와 제작을 위한 제조공법을 확립하고, 이를 이용해 제작된 광섬유 센서 케이블의 신뢰성 특성을 평가하였다. 설계 제작된 광섬유 센서 케이블의 구조는 멀티모드광섬유(MMF) 에 0.9 mm Tight buffer를 코팅하고, 광심선 주위에 아라미드 얀을 삽입시킨 후 고문자 수지를 적용하여 외부 피복 (jacket)을 하였다. 제작된 광섬유 센서 케이블의 외경 측정결과 기준치 ($2.95\;{\pm}\;0.03$ mm)를 모두 만족하였고, 850 nm 파장에서의 광 손실 측정 결과 4.0 dB/km 이하였다. 또한 주요 항목의 신뢰성 특성 시험결과, 인장강도는 8~10 kg의 인장력을 갖으며 온도순환시험 ($-30^{\circ}C\;{\sim}\;+75^{\circ}C$)에서의 광 손실은 0.6 dB 이하로 나타나 침입자 감지용 광섬유 센서 케이블로 적합함을 확인할 수 있었다.

• Journal of the Korean association of regional geographers
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• v.8 no.2
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• pp.270-279
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• 2002

1997년 IMF 경제위기 이후 한국사회의 뚜렷한 변화의 하나는 빈부격차의 확대와 함께 사회계층의 양극화가 진행되고 있다는 점이다. 이 논문의 목적은 사회적 양극화의 주요 원인은 무엇이며, 사회적 양극화가 공간적으로는 어떻게 나타나는가를 서울을 사례로 하여 규명하는 데 있다. 서구 선진자본주의 국가에서 사회적 양극화에 대한 논의는 이미 1990년대 초 세계화 또는 세계도시가 주요한 연구주제로 등장하면서 시작되었다. 1980년대 이후 선진자본주의 국가를 중심으로 한계에 도달한 포드주의 축적체계가 포스트 포드주의로 급속히 전환되면서 사회적 양극화가 자본의 유연화 및 세계화 전략과 맞물리는 현상으로 인식되었기 때문이다. 이런 점에서 최근 전개되고 있는 한국의 사회적 양극화는 서구 선진국과 유사하다. 1997년 경제위기 이후 세계화가 급속히 진행되는 가운데 지식기반경계의 대두로 고소득 전문직이 등장하는 반면, 중산층의 몰락과 더불어 임시적 고용이 확대되고 실업이 만성화되는 등 자본의 세계화와 유연화 과정에서 나타나는 양극화 양상이 보이기 때문이다. 이와 같은 맥락에서 한국의 사회적 양극화는 이미 1990년대 초부터 진행되어 왔으며, IMF 경제위기는 단지 그러한 사회적 양극화를 급속히 진행시키는 방아쇠 역할을 하였다고 할 수 있다. 그러나 양국의 사회적 양극화는 직업구조와 임금소득의 격차만으로 설명하기 어려운 또 다른 특성을 갖는다. 왜곡된 시장구조에서 무엇보다도 부동산과 같은 자산소득의 격차가 큰 역할을 하기 때문이다. 서울은 이와 같은 한국의 사회적 양극화가 한 도시 내에서 전형적으로 전개되는 곳이라고 할 수 있다. 한국 내 어떤 도시보다도 세계화되어 있고 전문지식을 기반으로 하는 산업이 발달하고 있기 때문이다. 서울의 사회적 양극화는 공간적으로도 나타난다. 일반적으로 서울은 크게 주거지로서는 공동화되고 있는 중구 종로구 용산구 등 사대문안의 구도심지역, 강남구 서초구 송파구 등을 중심으로 한 1970년대 이후 계획적으로 계발된 이른바 강남의 신흥주택 및 신산업 지역, 영등포구 구로구 금천구 성동구 동대문구 등 제조업 중심의 구 산업 및 저소득층 주거지역 그리고 그 나머지 강북 강서 강동 등의 전형적인 주거지역 등 4개 유형으로 지역이 구분된다. 그러나 IMF 경제위기 이후에 강남구 서초구 송파구를 중심으로 하는 고소득증의 주거지와 그 나머지 주거지로 공간적 양극화가 이루어지고 있다. 사회적 양극화의 이와 같은 공간화 과정에는 자산소득의 격차를 확대하는 강남구 서초구 송파구의 높은 지가 및 아파트 가격이 중요한 역할을 하고 있다. 높은 부동산 가격이 이 지역에 대한 일종의 진입장벽을 참음으로써 고소득층에 의한 공간독점을 가능하게 하기 때문이다. 공간적 양극화를 촉진하는데는 지하철 및 문화복지시설의 집중 둥 불균형적인 공공투자와 강북에서 이전한 명문고등학교를 중심으로 형성된 8학군 등 양호한 교육환경 또한 중요한 역할을 하고 있다. 서울의 사례에서 확인할 수 있듯이, 한국에서의 사회적 양극화는 직업구조와 임금소득이라는 일반적인 요인 외에도 부동산 가격 및 소득 그리고 생활인프라의 격차를 통해 공간적 양극화물 야기하고 있다. 이러한 현상이 한국내 다른도시에서도 전개되고 있는지, 공간적 양극화로 인한 도시문제는 무엇이고 대처방안은 무엇인지 등에 대해서 후속연구가 요구된다.

• Journal of Internet Computing and Services
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• v.10 no.6
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• pp.99-111
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• 2009

The result of Image segmentation, an indispensable process in image processing, significantly affects the analysis of an image. Despite the significance of image segmentation, it produces some problems when the variation of pixel values is large, or the boundary between background and an object is not clear. Also, these problems occur frequently when many objects in an image are placed very close by. In this paper, when the shape of objects in an image is circular, we proposed an algorithm which segment an each object in an image using the geometric characteristic of circular shape. The proposed algorithm is composed of 4 steps. First is the boundary edge extraction of whole object. Second step is to find the candidate points for further segmentation using the boundary edge in the first step. Calculating the representative circles using the candidate points is the third step. Final step is to draw the line connecting the overlapped points produced by the several erosions and dilations of the representative circles. To verify the efficiency of the proposed algorithm, the algorithm is compared with the three well-known cell segmentation algorithms. Comparison is conducted by the number of segmented region and the correctness of the inner segment line. As the result, the proposed algorithm is better than the well-known algorithms in both the number of segmented region and the correctness of the inner segment line by 16.7% and 21.8%, respectively.

• The Journal of Korean Philosophical History
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• no.52
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• pp.157-183
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• 2017

Korean Modernization is the period which Western Culture is settled as common sense, but modern introsepction of Confucianism acted as a sign to ask what is the basis of Korean modern subject. Park Eun-Sik transformed the basis of our thinking from Confucianism to the philosophy of Wang Yangming in the crash time of the Confucianism metaphysical structure. Park Eun-sik organized Definition of Real Me(眞我論) with the idealogical basis, that is, benevolence of the whole creation of the universe(萬物一體之仁) and the origin of the mind(良知) of Wang Yangming. He tried to realize the Basis of Confuciasism in the modern era with the origin of the mind(良知). And also he tried to figure out the origin of Confucianism by The public(民衆). He suggested the Public(民衆) as the unity to realize the Confucianism as equalitarianism. Park Eun-Sik declared the thought of great unity and peace of Korea(大同平和思想) with the idea of Real Me(眞我論) and benevolence of the whole creation of the universe(萬物一體之仁). Great unity and peace of Korea(大同平和思想) is based with the origin of the mind(良知) of Wang Yangming and is realized to be fulfilled as the thought of great unity and peace of Korea(大同平和思想).

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.1
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• pp.287-325
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• 2017

Considering the development of aerospace, military science and technology since the 20th century, the sky is very important for the nation's existence and prosperity. The proverb "Whosoever commands the space commands the world itself!" emphasizes the need for the command of the air. This essay is the first study on the status of airspace after reunification. First, the territorial airspace is over the territory and territorial sea, and its horizontal extent is determined by the territorial boundary lines. Acceptance of the present order is most reasonable, rather than attempting to reconfigure through historical truths about border issues, and it could be supported by neighboring countries in the reunification period. For peace in Northeast Asia, the reunified Korea needs to respect the existing border agreement between North Korea and China or Russia. However, the North Korean straight baselines established in the East Sea and the Yellow Sea should be discarded because they are not available under United Nations Convention on the Law of the Sea. It is desirable for the reunified Korea to redefine the straight baselines that comply with international law and determine the territorial waters up to and including the 12-nautical mile outside it. Second, the Flight Information Region (hereinafter "FIR") is a region defined by the International Civil Aviation Organization (hereinafter "ICAO") in order to provide information necessary for the safe and efficient flight of aircraft and the search and rescue of aircraft. At present, Korea is divided into Incheon FIR which is under the jurisdiction of South Korea and Pyongyang FIR which is under the jurisdiction of North Korea. If North Korea can not temporarily exercise control of Pyongyang FIR due to a sudden change of circumstances, it is desirable for South Korea to exercise control of Pyongyang FIR, and if it is unavoidable, ICAO should temporarily exercise it. In reunified Korea, it is desirable to abolish Pyongyang FIR and integrate it into Incheon FIR with the approval of ICAO, considering systematic management and control of FIR, establishment of route, and efficiency of management. Third, the Air Defense Identification Zone (hereinafter "ADIZ") is a zone that requires easy identification, positioning, and control of aircraft for national security purposes, and is set up unilaterally by the country concerned. The US unilaterally established the Korea Air Defense Identification Area (KADIZ) by the Declaration of Commitment on March 22, 1951. The Ministry of Defense proclaimed a new KADIZ which extended to the area including IEODO on December 13, 2013. At present, North Korea's military warning zone is set only at maritime boundaries such as the East Sea and the Yellow Sea. But in view of its lack of function as ADIZ in relations with China and Russia, the reunified Korea has no obligation to succeed it. Since the depth of the Korean peninsula is short, it is necessary to set ADIZ boundary on the outskirts of the territorial airspace to achieve the original purpose of ADIZ. Therefore, KADIZ of the reunified Korea should be newly established by the boundary line that coincides with the Incheon FIR of the reunified Korea. However, if there is no buffer zone overlapping with or adjacent to the ADIZs of neighboring countries, military tensions may rise. Therefore, through bilateral negotiations for peace in Northeast Asia, a buffer zone is established between adjacent ADIZs.

• Korea journal of population studies
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• v.20 no.1
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• pp.47-63
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• 1997

Problems concerning the vital registration system and its management, errors and methods to adjust them in the vital registration data in Korea have been studied. It is found that birth and death registration rates were above 95% in 1994. The registration rates rose rapidly since 1970 due to 1) simplification of registration form, 2) improving accessibility by allowing registration at the current residence, 3) enforcing fine against non-registration, and 4) improvements in social security system. However, there should be some continuing efforts for further improvement of the vital registration system. The content error in the data could be substantially reduced following the rapid rise of the registration rates in the 1980s, though this has never been actually studied. There are still substantial registrations with false date of death. The false date of events may affect the computed vital rates specially when the registration rates are rapidly rising. Especially the death rates of the young can be seriously affected. A study on the data in the 1970s shows that death of age between 3 to 19 has been over-registered up to 67% compared with the expected. It is a serious matter that some researchers analyze the registration data without adjusting the errors. It is strongly recommended for the Government Statistical Office to undertake a study on the registration behavior of the people.

• Journal of the Korean Data and Information Science Society
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• v.26 no.6
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• pp.1353-1366
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• 2015

These days Shewhart control chart for evaluating stability of the process is widely used in various field. But it must follow strict assumption of distribution. In real-life problems, this assumption is often violated when many quality characteristics follow non-normal distribution. Moreover, it is more serious in multivariate quality characteristics. To overcome this problem, many researchers have studied the non-parametric control charts. Recently, SVDD (Support Vector Data Description) control chart based on RBF (Radial Basis Function) Kernel, which is called K-chart, determines description of data region on in-control process and is used in various field. But it is important to select kernel parameter or etc. in order to apply the K-chart and they must be predetermined. For this, many researchers use grid search for optimizing parameters. But it has some problems such as selecting search range, calculating cost and time, etc. In this paper, we research the efficiency of selecting parameter regions as data structure vary via simulation study and propose a new method for determining parameters so that it can be easily used and discuss a robust choice of parameters for various data structures. In addition, we apply it on the real example and evaluate its performance.

• The Journal of the Acoustical Society of Korea
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• v.34 no.1
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• pp.36-45
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• 2015

Recently, a lot of studies have been made about the methods used to generate turbulent velocity fields stochastically in order to effectively predict broadband flow noise. Among them, the FRPM (Fast Random Particle Mesh) method which generates turbulence with specific statistical properties using turbulence kinetic energy and dissipation obtained from the steady solution of the RANS (Reynolds Averaged Navier-Stokes) equations has been successfully applied. However, the FRPM method cannot be applied to the flow noise problems involving intrinsic unsteady characteristics such as centrifugal fan. In this paper, to effectively predict the broadband noise generated by centrifugal fan, U-FRPM (unsteady FRPM) method is developed by extending the FRPM method to be combined with the unsteady numerical solutions of the unsteady RANS equations to generate the turbulence considered as broadband noise sources. Firstly, an unsteady flow field is obtained from the unsteady RANS equations through CFD (Computational Fluid Dynamics). Then, noise sources are generated using the U-FRPM method combined with acoustic analogy. Finally, the linear propagation model which is realized through BEM (Boundary Element Method) is combined with the generated sources to predict broadband noise at the listeners' position. The proposed technique is validated to compare its prediction result with the measured data.

• Journal of Korean Philosophical Society
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• v.126
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• pp.79-108
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• 2013

Is the development of linguistic competence due to the learning process or the maturational process? According to Piaget, its development is a genuine learning process involving authentic constructions with gradual disclosure of new possibilities. But According to Chomsky, the acquisition of linguistic competence is due to a genetically conditioned maturational process. So it merely involves the actualization of a set of possibilities existing from the beginning Consequently, Piaget supposes that interaction with the environment plays a shaping role, while Chomsky allows it to have a mere triggering role. In broad respective, Chomsky supposes the rationalism that knowledge is largely inborn, while Piaget in the constructivist position which strives to find a middle course between radical rationalism and radical empiricism. In the one hand, an ultra-rationalistic concept such as 'fixed nucleus' supposed by Chomsky is, in my eye, nor plausible. In the other hand, if Piagetian constructivism is to be sustained, it must be sustained independently of its dubious biological fundament, and merely as a developmental psychological theory. In one word, we need to synthesize Piagetian cognitive approach and Chomskian syntactical, in order to explain exactly the source of human linguistic competence.

• Korean Journal of Comparative Education
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• v.27 no.3
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• pp.23-48
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• 2017

The purpose of this study is to analyze the meaning of Joseon school or Korean school (hereafter, Korean school) education in the context of Japanese foreign education through oral history of Korean residents in Japan. I focused on how educational experience of Korean residents who were born and raised in Japan formed through the Korean school education was implemented and applied in Japanese society. Participants were 7 Korean residents in Japan who were educated at Korean school. They all grew up in Kansai region including Osaka Prefecture and Hyogo Prefecture. The oral data was collected three times from September 17, 2014 to February 29, 2016. The oral interviews were conducted two times, two hours per session. As to the analysis of oral data, we first prepared the classification table according to the detailed themes and then cross-checked between the history of Korean residents in Japan as well as related literatures and the memories of the oral interviewees. The results of this study are as follows. The oral interviewees recognized that there was no relation between the development process of foreign education policy in Japan and Korean school education. They said that the education of foreigners in Japan was "consistent with the exclusion of Korean schools." However, unlike the Japanese central government, local governments implemented the policies such as providing subsidies to Korean schools, accepting the graduates of Korean schools in public and private universities, and providing fare discounts for students of Korean schools in local private railways.