• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.437-442
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• 1998

Film boiling is the heat transfer mechanism that can occurs when large temperature differences exist between a cold liquid and hot material. In the nuclear reactor safety analysis, film boiling has become an important issue in recent years. During severe accident, hot molten corium fall into relatively cool water, and fragment into spheres or sphere-like particles. If the steam explosion is triggered, the thermal energy of corium is converted into the mechanical energy that can threaten the integrity of reactor vessel or reactor cavity. One of the important concerns in the heat transfer analysis during pre-mixing stage is the film boiling heat transfer between the corium and water/steam two-phase flow. Until now, considerable works on film boiling heat been performed. However, there is no available correlation adequate for severe accident analysis. In this study, boiling heat transfer correlations have been developed, and their applicable ranges heat been enlarged and their prediction accuracy has been enhanced.

• 제어로봇시스템학회논문지
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• 제13권6호
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• pp.560-567
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• 2007

The objective of this research is to optimize the designing parameters of the parallel manipulator with large orientation workspace at the boundary position of the constant orientation workspace (COW). The method uses a simple genetic algorithm(SGA) while considering three different kinematic performance indices: COW and the global conditioning index(GCI) to evaluate the mechanism's dexterity for translational motion of an end-effector, and orientation workspace of two angle of Euler angles to obtain the large rotation angle of an end-effector at the boundary position of COW. Total fifteen cases divided according to the combination of the sphere radius of COW and rotation angle of orientation workspace are studied, and to decide the best model in the total optimized cases, the fuzzy inference system is used for each case's results. An optimized model is selected as a best model, which shows better kinematic performances compared to the basis of the pre-existing model.

• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1395-1403
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• 2016

In recent years, researches of security threats reported that various types of social engineering attack were frequently observed. In this paper, we propose secure keypad scheme for mobile devices. In our scheme, every edge of keypad is linked each other, and it looks like a sphere. With this keypad, users input their password using pre-selected grid pointer. Because of circulation of the keypad layout, even though the attacker snatch the user password typing motion through the human eyes or motion capture devices, attacker do not estimate the original password. Moreover, without the information of grid pointer position, the attacker do not acquire original password. Therefore, our scheme is resistant to password guessing attack.

• 한국학교ㆍ지역보건교육학회지
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• 제1권1호
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• pp.1-9
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• 2000

The purpose of this study were to assess the effect on health promotion behavior of health instruction in elementary school and to provide a basis of school health education. Subjects of this study were random sampled 80 students for control group in elementary 6th grade students. the treatment group systematically studied five sphere instruction: individual hygiene, disease prevention, first-aid & safety, oral health, health & nutrition in two hours a week, from April 20, till July 10. Each group was pre-tested and post-tested by health behavior promotion questionnaire. The conclusions as follows; 1. Compare analysis of control group and treatment group in the pre-test according to health condition of children were no significant difference physical health condition, health anxiety, disease-absent(P>.05). 2. Health promotion behaviors in the post-test according to concern quotient significantly correlated with individual hygiene(r=.249, P<.05), disease prevention(r=.477, P<.01), oral health(r=.228, P<.05), health & nutrition(r=.323, P<.01) in the treatment group, on the contrary the disease prevention, first-aid & safety, oral health, health & nutrition(P>.05). 3. The difference of health promotion behavior within & between group were as follow; 1) The difference of individual health hygiene with in the treatment group was significant in pre-post test, the comparison of the two groups was significant difference in post-test(treatment group: $3.965{\pm}.568$, control group: $3.645{\pm}.573$). 2) The difference of disease prevention with in the treatment group was significant in pre-post test, the comparison of the two groups was significant difference in post-test(t group : $3.475{\pm}.619$, c group: $3.964{\pm}.600$). 3) The difference of first-aid & safety with in the treatment group was significant in pre-post test, the comparison of the two groups was significant difference in post-test(t group : $3.700{\pm}.466$, c group: $4.140{\pm}.545$). 4) The difference of oral health with in the treatment group was significant in pre-post test, the comparison of the two groups was significant difference in post-test(t group: $3.163{\pm}.665$, c group: $3.753{\pm}.544$). 5) The difference of health & nutrition with in the treatment group was significant in pre-post test, the comparison of the two groups was significant difference in post-test(t group : $3.255{\pm}.515$, c group: $3.698{\pm}.558$).

• 한국지능시스템학회논문지
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• 제12권4호
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• pp.306-310
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• 2002

본 논문은 글자 문서를 배경으로 사용자의 손가락 이동에 의하여 일정한 영역을 그린 후, 영역내의 한글 영상을 편집 가능 한 에디터에 출력하는 시스템을 구현하였다. 영상의 전처리 단계에서는 문서 배경과 손 영역을 분리하고 최대 원형 이동법을 이용하여 손의 무게 중심점을 추출한다. 원형 패턴 벡터 알고리즘을 사용하여 손을 인식한 후, 거리 스펙트 럼으로 손가 락 위치를 찾는다. 손가락의 움직임에 의해 선택되어진 문자 영역을 추출한 후, 한글 자소 간 히스토그램을 이용하여 추출 된 문자 이미지 영역에서 문자단위로 분할하고 다양한 크기의 문자를 표준화한다. 퍼지 추론을 적용한 원형 패턴 벡터 알고리즘을 이용하여 표준 패턴문자와 입력문자의 특징벡터를 비교하여 문자를 인식하게 함으로써 사용자가 원하는 영역의 문자들을 수정 가능한 문서로 변환하였다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.205-211
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• 2002

The purpose of this paper is 1) to extract managerial factor into each cell which is classified by the characteristic grill of new products 2) to construct a management model of new product development for korean companies. For this purpose, the characteristic grill of new products is classified by which is market/technology sphere. Moreover the focus of this analysis is on examination of success/failure factors, which have an important effect upon new product success or failure. The variables for this study were selected from literature survey and pre-interview was implemented specially. The subject of study was project leaders of electronics industry where have taken the leading part in product development activities in Korean manufacturing industries. Enquete survey was conducted in each firm and project managers were asked to respond. Conclusion of this study based on many significant results gained by the various multi-variate analysis are summarized as follows. First, it can he noted that success/failure factors are different by each classified model and characteristic grill of a new product. Second, it has been identified that the important factors of success products were technical & management support and market ability, the important factor of failure product were lacking in ability of technical development and R&D management system construction. This paper presents some useful guidelines in strategic and managerial aspects for development of new products. Concurrently, the model of this study should be a great practical approach for application of actual affairs.

• Journal of Information Science Theory and Practice
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• 제2권2호
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• pp.6-15
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• 2014

Initial based disambiguation of author names is a common data pre-processing step in bibliometrics. It is widely accepted that this procedure can introduce errors into network data and any subsequent analytical results. What is not sufficiently understood is the precise impact of this step on the data and findings. We present an empirical answer to this question by comparing the impact of two commonly used initial based disambiguation methods against a reasonable proxy for ground truth data. We use DBLP, a database covering major journals and conferences in computer science and information science, as a source. We find that initial based disambiguation induces strong distortions in network metrics on the graph and node level: Authors become embedded in ties for which there is no empirical support, thus increasing their sphere of influence and diversity of involvement. Consequently, networks generated with initial-based disambiguation are more coherent and interconnected than the actual underlying networks, and individual authors appear to be more productive and more strongly embedded than they actually are.

• Medical Lasers
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• 제10권4호
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• pp.229-237
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• 2021

Background and Objectives To assess the effectiveness of overnight orthokeratology (OK) in myopia using a new contact lens design over a one-month wearing period. Materials and Methods Participants were required to have myopia between -3.00 and -7.50D and astigmatism ≤ 2.00 D to participate in the study. The participants underwent OK with the White OK lens^® (Interojo, Pyungtek, Korea), which has a 6-curve lens design. Participants were assessed at weeks 1, 2, and 4 using slit-lamp bio-microscopy, and tested for refraction, uncorrected distance visual acuity, and corneal topography. Success was defined as achieving a Logarithm of the Minimum Angle of Resolution (logMAR) ≤ 0.1. Results A total of 46 eligible subjects with a mean age of 23.11 ± 7.89 years were recruited. Baseline logMAR was 1.18 ± 0.30 and a consistent decrease in logMAR was observed from week 1 to week 4. The success rate was 95.35% at week 4. The mean sphere significantly decreased from a mean pre-fitting value of -4.58 ± 1.28 D to a mean value of -0.65 ± 0.69 D at week 4 (p < 0.0001). Statistically significant corneal flattening was detected during keratometry at week 4. Conclusion Overnight OK with the White OK lens is effective for the correction of moderate and high myopia with astigmatism over a one-month wearing period.

• Acta Via Serica
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• 제9권1호
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• pp.67-90
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• 2024

India, Southeast Asia in general, and Siam in particular share a long history of cultural and commercial relations. Located in each other's extended neighbourhood, India and Thailand have a shared maritime boundary in the Andaman Sea. Situated in the strategic position, midway between West Asia on the one hand and East Asia on the other, India and Siam combined played a significant role in the maritime transactions in Asia and beyond. The geographical proximity between India and Siam led to multifaceted maritime interactions and exchanges. Siam was in the Indian sphere of cultural, religious, philosophical, technical, and linguistic influence much before the Common Era. The cultural and mercantile networks between India and Siam are well-attested by archaeological and literary sources. The archaeological findings in Siam and other Southeast Asian countries have revealed the dynamic trade and cultural exchange between India and Southeast Asia since the pre-Common Era. The Takola (modern Takua Pa) area served as a more suitable landing place for Indian merchants and there existed the settlement of the Indian mercantile community. Ligor (Nakhon Si Thammarat), Jaya (Chaiya), Patalung (Phatalung), U Thong, Ban Don Tha Pet, Ban U Taphao, Khao Sam Kaeo, and many other sites in Siam have brought to light a large variety of objects which demonstrate that ancient Siam had close mercantile contact with India as well as the Mediterranean world and China. The paper discusses in detail the cultural and trade links between India and Siam and their impact on the Maritime Silk Road.

• 한국항공우주법학회:학술대회논문집
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• 한국항공우주법학회 2008년도 제40회 국제학술발표대회
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• pp.219-231
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• 2008

" Analyzing on an object in the sphere of domestic law with the method of international law" has been already on the horizon in international law. For the lawyers of international law and space law, it is quite natural that they utilize the method of international law, whatever objects they may choice. The reason is that the characteristic of international law do not depend upon object in itself, but depend upon method in itself. The object of this paper is the idea of Peaceful Use(IPU or PU) in Japanese Space Policy. The method to be applied to this analysis is the international law's interpretation theory on legal principles, i.e., the method of international law. One of the aims of this paper is to explain critically the need of review on IPU in Japanese Space Policy; in particular with respect to the positive reconstruction of IPU through historical analyzing on the transfiguration and the mere shell of the Post-War Japanese Pacifism(PJP) as the starting point of IPU The historical process of the transfiguration and the mere shell is as followed .i.e.," from the ultranationalism in the pre-war Japan to PJP in the post-war Japan, from PJP to IPU, and from IPU to IPU's regression. In particular with respect to the interpretation theory, the meaning of the teleological, aims and objects school's approach on the interpretation of legal principles(P) has been emphasized. The reason is that the promising development of IPU will be realized by cooperating with the interpretation theory on P in international law. At the end of the beginning, I'd like to quote K. Marx's thesis in order to make the positions and missions the lawyers of international law and space clear. It is as follows, i.e.," THE PHILOSOPHERS HAVE ONLY INTERPRETED THE WORLD IN VARIOUS WAYS - THE POINT, HOWEVER IS TO CHANGE IT.