• 농촌의학ㆍ지역보건
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• 제16권1호
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• pp.61-69
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• 1991

Serodiagnosis of Clonorchis sinensis infections will probably be a first choice tool for screening of clonorchiasis in a future because of increasing difficulties in collection and examination of stools. The sensitive test such as ELISA can he used effectively. However there are some limitations in serological diagnosis for the detection of serum antibody. One of the major problems is the non-specificity of the antigens which produce cross reaction with other helminthic infection sera. To solve this problem. many investigators have tried to purify the antigens used. In this study, we determined the antigenic profile of the crude saline extract antigen of C. sinensis at early developmental stage based on SDS-PAGE and immunoblotting techniques for the purpose of understanding the nature of C. sinensis worm antigen The following results were obtained : 1) The SDS-PAGE showed many protein hands ranging from 10Kd to 91Kd relative molecular weight. Among them, 66, 46, 40, 33, 27, 24, 16, 14 and 10Kd bands were observed as a principle bands. The protein components of C. sinensis changed chronologically during their early developmental period. 44Kd band was stained unclearly in antigen of 2 weeks worm, but changed to concentrated state in antigen of 5 weeks worm. 35Kd band was found in antigen of 2 weeks worm, however this band was disappeared in antigen of 5 weeks worm. 22Kd band also lost its staining property gradually. 2) In spite of differences in antigenic profile, there was no differences in the data obtained by microplate ELISA using each antigen preparation. Absorbance value began to rise in between 2 to 3 weeks after infection. 3) By EITB. serum antibody recognized major protein bands with molecular weight of 91, 85, 63, 46, 40, 33, 24, 14 and 10Kd hand respectively. Among them 66, 33, 17 and 14Kd bands were observed as non-specific band because they reacted even in normal control sera. Generally, gradual increase of positive reactions were observed as the infection period of C. sinensis was prolonged. In other hand, the reaction of 10Kd hand did not occurred when 26th week sera was tested. 4) The positive reactions using antigens of 2 weeks worm, especially on 40 and 24Kd bands, were most strong and sharply demarcated compared to those of 3~5 weeks worm antigen.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.744-749
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• 2005

In this paper, a lens actuator for mobile devices is proposed using stack type piezoelectric materials. In general, the deformation of PZT actuators is not enough for lens motion when the allowed voltage is applied. The small stroke problem can be solved by accumulating a lot of small displacements in high frequency. In this paper, a new inch-worm type model for focusing actuator is suggested based on the interaction of inertial and frictional forces. Theoretical analysis and simulation using ANSYS are performed to verify the feasibility of the inch-worm PZT actuator model. Various types of clamps are considered to determine the effect of frictional force on the motion, and appropriate clamp-actuator models are proposed. The proposed models are experimentally verified and the experimental results show high correspondence with theoretical and simulated values. The inch-worm type focusing actuator enable a large stroke with 7.79 mm/sec with 10kHz and 10V.

• 한국통신학회논문지
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• 제32권8B호
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• pp.529-538
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• 2007

본 논문에서는 2003년 전 세계의 인터넷망에서의 심각한 소통 장애를 일으켰던 슬래머 웜 보안공격의 전파 전과정을 NS-2를 이용한 시뮬레이터로 분석하였다. 기존 연구에서는 Detailed Network-Abstract Network(DN-AN) 모델 기반의 Abstract Network-Abstract Network(AN-AN)모델을 이용한 분석이 수행되었다. 이러한 AN-AN모델은 패킷 레벨까지 정확한 분석이 가능하지만, 초기 300초의 감염구간을 모의실험 하는데 240시간이 소요되는 시간상 문제점이 있었다. 본 논문에서는 이러한 문제점을 해결하기 위한 축소된 모델링 기법을 제시하여 모의실험에 필요한 소요시간을 단축함으로써 소통 장애가 일어난 3.5시간을 107시간에 분석할 수 있었다. 아울러 기존 분석에서는 감염 호스트가 인위적인 치료나 격리 조치가 있을 때까지는 모두 동작하는 것으로 가정하였지만, 슬래머의 과도한 감염 트래픽으로 중계 라우터의 동작이 중지되는 현상에 의해 해당 장비가 감염과정에서 자연적으로 격리되는 격리율 0.00022도 함께 고려하였다. 모의실험 결과, 국제관문국의 국외$\Longrightarrow$국내방향은 4,787초에 정상 상태로 돌아온 반면, 국내$\Longrightarrow$국외방향이 3.5시간동안 포화가 되어 소통 장애가 지속됨을 알 수 있었다.

• 한국콘텐츠학회논문지
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• 제5권5호
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• pp.172-181
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• 2005

유해 트래픽의 최근 유형은 트래픽 폭주 공격에서 더 발전되어 웜, 봇과 같이 다양화, 지능화, 은닉화, 자동화되어 기존의 방법으로는 탐지하기 어렵다. SNMP 기반의 추이 분석 방법은 인터넷 사용의 큰 비중을 차지하고 있는 정상적인 P2P(메신저, 파일 공유) 및 기타 응용 프로그램 사용 시 유해 트래픽으로 분류하는 문제점과, 웜 및 봇과 같은 발전된 유해 트래픽을 분석해내지 못하는 큰 취약점을 가지고 있다. 제안한 방법은 프로토콜 추이 및 포트 트래픽 분석 방법을 적용하였다. 발생된 트래픽을 프로토콜, well-known포트, P2P포트, 기존 공격 포트, 특정 포트로 분류하고 이상 가중치를 적용하며, 실험 결과 P2P 트래픽 분석, 웜 및 봇 탐지, 트래픽 폭주 공격 등을 효과적으로 검출 할 수 있었다.

• 한국환경과학회지
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• 제20권1호
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• pp.137-146
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• 2011

In this research, food waste source reduction model for apartment was investigated. In spite of prohibition of direct landfill of food waste and continuous efforts made by government and local government, food waste production increases steadily. Recycling ratio of the food waste increases every year, but its products have many problems like low quality, stability, salt, odor etc. Household occupies 63.3% of whole food waste production and this is subject to be a key factor to control food waste. We surveyed S apartment in Kwangju city as a model case, in which administrative office and women's association adopted clean plate eating, separation of raw food waste and earth worm composting as a series of method for source reduction and recycling inside the apartment. With the help of residents' participation and practice, food waste production decreased 15.6% from 0.31 g/capita/day in 2007 to 0.26 g/capita/day in 2009 (domestic average 0.30 g/capita/day). Separation of raw food waste and its composting using earth worm were very effective, and were subject to resolve the problems of present food waste treatment technologies. And earth worm composting was very useful in environmental, economical, societal and educational aspects. Instead of economical incentive, educational programs about food value, environmental problem and critical method for food waste separation were more effective for promotion of source reduction. From the analyses on the process and success factors in this model, we could conclude that leader's role was one of the key factors for the settlement of source reduction, and that was to understand the seriousness of the food waste and to seek solution, to test techniques, and to practice by oneself. Furthermore, networking and collaboration among residents, local government, NGO and local press promoted residents' participation, and it was through various education and investigation. Finally, source reduction and self recycling model of food waste in the apartment, that applies separating raw food waste and earth worm composting based on the collaboration among residents, local government, NGO, and local press, should be disseminated, and environmental policy also should be changed to make it possible.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제11권4호
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• pp.19-38
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• 2007

Graph theory is becoming increasingly significant as it is applied of mathematics, science and technology. It is being actively used in fields as varied as biochemistry(genomics), electrical engineering(communication networks and coding theory), computer science(algorithms and computation) and operations research(scheduling). The powerful results in other areas of pure mathematics. Rhis paper, besides giving a general outlook of these facts, includes new graph theoretical proofs of Fermat's Little Theorem and the Nielson-Schreier Theorem. New applications to DNA sequencing (the SNP assembly problem) and computer network security (worm propagation) using minimum vertex covers in graphs are discussed. We also show how to apply edge coloring and matching in graphs for scheduling (the timetabling problem) and vertex coloring in graphs for map coloring and the assignment of frequencies in GSM mobile phone networks. Finally, we revisit the classical problem of finding re-entrant knight's tours on a chessboard using Hamiltonian circuits in graphs.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.65-66
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• 2010

To improve the gear noise quality, gear tooth grinding machine are widely used in automotive industry. While using the gear profile grinding machine to improve the gear tooth quality of the transmission, several defects such as chattering, tooth waves that cause the gear noise occasionally happened. But it is very difficult to solve that problem, because there is no one who knows the setting up the optimal grinding condition appropriately. The abnormal manufacturing conditions which make the gear noise make the engineer to spend a lot of time, effort, and money. Due to demands for solving the serious abnormal gear noise happened in the new FF 6th stage automatic transmission in the mass product stage, the vibration checking process in the worm wheel axis, work rotation and fixed axis of the grinding machine were adapted to find the root causes. As a result, gear profile wave are affected by the work rotation axis's unbalance which is caused by worm wheel feeding speed. And a primary and the secondary grinding feeding speed, cutting oil, work fixed forces are also proved as the important factors. After setting up the grinding condition reported in this paper, it was adapted successfully to the grinding machine to manufacture the new FF 6th speed automatic transmissions' output gear. The gear noise was dramatically disappeared and the process and results will offer good guides to the engineers who manufacture the gear with the grinding machine.

• 한국소음진동공학회논문집
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• 제20권7호
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• pp.665-671
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• 2010

To improve the gear noise quality, gear tooth grinding machine are widely used in automotive industry. While using the gear profile grinding machine to improve the gear tooth quality of the transmission, several defects such as chattering, tooth waves that cause the gear noise occasionally happened. But it is very difficult to solve that problem, because there is no one who knows the setting up the optimal grinding condition appropriately. The abnormal manufacturing conditions which make the gear noise make the engineer to spend a lot of time, effort, and money. Due to demands for solving the serious abnormal gear noise happened in the automatic transmission in the mass product stage, the vibration checking process in the worm wheel axis, work rotation and fixed axis of the grinding machine were adapted to find the root causes. As a result, gear profile wave are affected by the work rotation axis's unbalance which is caused by worm wheel feeding speed. And a primary and the secondary grinding feeding speed, cutting oil, work fixed forces are also proved as the important factors. After setting up the grinding condition reported in this paper, it was adapted successfully to the grinding machine to manufacture the new automatic transmissions' gear. The gear noise was dramatically disappeared and the process and the results will offer good guides to the engineers who manufacture the gear with the grinding machine.

• 한국통신학회논문지
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• 제28권7C호
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• pp.712-718
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• 2003

C.elegans 선충은 유전자 기능 연구에 주로 쓰이고 있으나, 변종들의 구분이 육안으로는 쉽지 않다. 이를 해결하기 위하여 컴퓨터 비젼을 이용하여 자동으로 분류할 수 있는 시스템이 연구 중이며, 이전 논문［1］에서 선충의 자동 분류 시스템에 사용될 영상의 전처리 과정에 대하여 서술한 바 있다. 본 논문에서는 전처리 된 영상 데이터를 이용하여 추출해 낼 수 있는 선충의 형태적 특징들을 제시한다. 선충의 크기와 관련한 특징과 자세에 관련한 특징으로 나누어, 각 특징의 추출 알고리즘을 수학적으로 표현하였다. 실험에서 제시된 형태적 특징 정보를 이용하여 직접 분류해 봄으로써 성능을 확인하였다. 분류 알고리즘은 Hierarchical Clustering을 사용하였다. 그 결과 실험에 이용된 선충의 4 종류 모두 90% 이상 옳게 분류되었다.

• 한국통신학회논문지
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• 제41권2호
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• pp.277-284
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• 2016

인터넷 서비스의 질을 떨어뜨리고 온라인 범죄를 유발시키는 네트워크 공격들은 오늘날 현대 사회에서 해결해야 될 문제 중 하나이다. 이러한 문제 해결을 위해 시그니처 IDS(Intrusion Detection System)라는 침입 탐지 시스템이 개발되었지만 이들은 기존에 알려진 유형의 공격만 탐지해 낸다. 결과적으로 알려지지 않은 공격들에 대해서는 탐지하지 못하기 때문에 네트워크 공격 탐지를 위한 근본적인 해결책이라 할 수 없다. 본 논문에서는 시그니처 IDS의 단점을 보완하고자 K-평균 알고리즘 기반의 네트워크 유해트래픽 탐지 방법을 제안한다.