비동기 카오스 비밀통신의 변복조 기술평가

곽부동,김성곤,최희주,변건식 동아대학교 정보기술연구소 2000 情報通信硏究所論文誌 Vol.8 No.1

During the past five years, there has been tremendous interest worldwide in the possibility of exploiting chaos in wideband communication systems. Many different demodulation techniques have been proposed up to date. They can be divided into two basic categories. In the first approach, like the conventional coherent demodulation techniques, the chaotic signal has to be recovered from the received noisy signal by synchronization. However, the chaotic synchronization techniques published to data are so sensitive to the channel noise and distortion that these techniques can not be used in radio communications. In the second approach, the demodulation is carried out nonsynchronization. This paper surveys the different chaotic communication techniques that can be implemented nonsynchronization and compares the threshold and BER of the different methods. Finally, FM-DCSK is introduced the first step for apply to wideband chaos digital CDMA, where the data is not limited by the inherent nonperiodic property of the chaotic signal.

V79 배양 세포에 있어 인삼추출물이 DNA복제 및 회복 합성에 미치는 분자생물학적 연구

卞富亨,徐富一,卞晟僖 대한본초학회 1999 大韓本草學會誌 Vol.14 No.2

본 연구는 인삼추출물이 DNA 복제 및 회복 합성에 미치는 영향을 조사하기 위해 수행되었다. DNA 복제 및 회복 합성도의 측정은 V79 chinese hamster lung cell의 핵 내 DNA에 [3H]-tymidine이 유입되는 양으로 측정하였다. 그 결과 인삼추출물의 농도(0~1ug/㎖)가 높을수록 점점 더 크게 감소하였다. 이와 같이 인삼추출물에 의하여 DNA 복제 합성도가 감소하는 현상은 농도가 더 높을수록 효과적인 것으로 보아 농도에 의존한다는 것을 알 수 있었다. 한편 DNA 회복 합성도에 인삼추출물이 미치는 영향을 알아보기 위해 우선 DNA를 손상시켰다. DNA를 손상시키는 물질은 여러 가지 있으나, 본 실험에서는 자외선과 methylmethane sulfonate(MMS)를 사용하였다. 이렇게 손상된 DNA가 인삼추출물(0~1ug/㎖)에 의하여 얼마나 회복되었는가를 알아보기 위하여 인삼추출물의 농도를 각각 달리하여 V79 cell에 첨가하였다. 그 결과 인삼추출물의 농도가 높을수록 DNA 회복합성도는 증가하였다. 이와 같이 인삼추출물이 DNA 복제 합성은 억제하고, DNA 회복 합성은 증가시키는 상반된 효과를 보여 주었다. 이러한 상반된 효과는 복제합성과 회복합성의 두 과정에서 서로 다른 효소체계가 관여하기 때문인 것으로 보인다. 인삼추출물이 DNA복제 및 회복합성에 미치는 영향에 대하여 보다 더 구체적인 분자생물학적 메커니즘 연구가 이루어져야 할 것이다.

분해성 폴리에틸렌 필름의 생분해 및 광분해성에 관한 연구

신부영,장상희,정병욱 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.2

Photo-biodegradable master batch was prepared by using mechanical and thermal oxidation that in general occur during polymer processing operation. Master batches were prepared by melt mixing in air circumstance, respectively. High density polyethylene(HDPE) sheets containing 20 wt.% photo-biodegradable M/Bs were prepared by compression molding and we observed the photodegradability under the mercury-vapor lamp. The sheet of containing M/B prepared above 95% of its original elongation and very brittle within 120 hours irradiation, however, pure HDPE sheet still retained about 80% original elongation for 120 hours irradiation. Under the natural sunlight, photo-biodegradable HDPE films lost about 98% of its original elongation at break for 8weeks outdoor exposure in summer. The common film still retained 75% of its original elongation at the same period. Surface morphology of the films was examined by using scanning electron microscopy(SEM). The effects of water on the mechanical properties and morphology of film were examined during the irradiation. In the case of biodegradation test, incubator test were performed simultaneously. Microorganism (fungi) growth in photo-biodegradable film surface was augmented by exposed time increasingly.

척수손상·비손상인의 신체부위별 신체구성 및 골밀도 비교

김성수,황부근,김태수,이충일,양정수,이동희 한국특수체육학회 2003 한국특수체육학회지 Vol.11 No.1

This study was designed to compare segmental body composition and bone mineral density in spinal cord-injured(SCIS; n=9, SCIA; n=9) and non-injured control(AB; n=9) subjects. Dual-energy X-ray absorptiometry(DEXA) was used to measure %body fat, body fat mass, lean body mass, bone mineral contents, and bone mineral density in total and various body regions(arms, legs, trunk). The present results showed that body fat mass and %body fat were significantly higher and lean body mass was significantly lower in the SCIS group compared to AB group, while there was no difference between the SCIA and AB group in those of parameters. In BMC, there was no difference among groups and in BMD, SCI group was significantly lower that AB group, but there was no difference between SCIA group and AB group. Based on these results, in can be suggested that long-term regular exercise can reduce the negative changes in body composition, bone mineral density by spinal cord injury.

대학생의 운동과 스포츠 장애에 관한 연구

황향희,이상진,부기원 강원대학교 체육과학연구소 2000 江原大學校附設體育科學硏究所論文集 Vol.- No.23

The purpose of this study was to survey and analyze the response of college students on the barriers to exercise and sport with 1,000 students(female : 500, male :500) on the Chunchon city in Kangwon province were answered by the questionnaire. Analyse of the data with 732(female:374, male:358) for the evaluation of the questionnaire can be acquired the more basis materials of sports environment for the university students. As result, we have the conclusion as follow. 1.There are no difference(P> .05) in their sex and factor of sport barriers, but there is a different(P <.001) between the factors of sport barriers. 2.Their major and factor of sport barriers weren't a difference, but there is a difference<P <.01) between the factors of sport barriers. 3.Whether they was a member of exercise group or not and factor of sport barriers. There is no significant differences according to whether they was a member of exercise group or not level at P> .05, but there is a difference(P <.001) between the factors of sport barriers. 4.In their grade and factor of sport barriers, there is a meaningful difference level at P <.01, but there is no difference between the factors of sport barriers level at P <.001. Group of 2d, 3d, 4th more disturbed than average in order of barriers of resources, club, and program, but the reflection of 1st grade;s group in order to barriers of resources, program, club, and satisfaction at the program. Approximately, 1st grade's reflection seemed level at average. 5.As a result of the analysis of variance that their sex, major, whether they was a member of exercise group or not, grade and the factors of sport barriers. Generally, they were so many disturbed by barriers of resources, and then they showed strong rejection symptoms toward high price they should pay for using exercise facilities. The college student's exercise and sports activities weren't disturbed by their health. In addition, there is no significant difference in the effect of interaction that in their sex, major, whether they was a member of exercise group or not, grade and the factors of sport barriers.

대청호 식물플랑크톤의 계절별 밀도변화와 주요종의 미세구조

이상희,강현숙,부성민 忠南大學校 環境問題硏究所 2002 環境硏究 Vol.20 No.-

The change of density and ultrastructure of representative phytoplankton in Daechungho was studied on May 30, August 1, September 10, and November 12, 2002. A total of 50 phytoplankton species were identified, representing 7 classes. A total of 646 phytoplanktons per 1 ㎖ at Seonchakjang (1% of Cyanophyceae, 19% of Chlorophyceae, 76% of Bacillariophyceae, 3% of Crysophyceae, and 1% Dinophyceae) and 1378 per 1 ㎖ at Hoeincheon (1% of Cyanophyceae, 19% of Chlorophyceae, 78% of Bacillariophyceae, and 2% of Crysophyceae) occurred on May 30. A total of 1141 phytoplanktons per 1 ㎖ at Seonchakjang (60% of Cyanophyceae, 24% of Chlorophyceae, 12% of Bacillariophyceae, and 2% of Crysophyceae) and 2566 per 1 ㎖ at Hoeincheon (55% of Cyanophyceae, 21% of Chlorophyceae, 23% of Bacillariophyceae, and 1% of Crysophyceae) occurred on August 1. A total of 1946 phytoplanktons per 1 ㎖ at Seonchakjang (74% of Cyanophyceae, 17% of Chlorophyceae, and 9% of Bacillariophyceae) and 984 per 1 ㎖ at Hoeincheon (39% of Cyanophyceae, 57% of Chlorophyceae, and 2% of Bacillariophyceae) occurred on September 10. A total of 364 phytoplanktons per 1 ㎖ at Seonchakjang (5% of Cyanophyceae, 44% of Chlorophyceae, 48% of Bacillariophyceae, and 1% of Crysophyceae) and 469 per 1 ㎖ at Hoeincheon (6% of Cyanophyceae, 46% of Chlorophyceae, and 46% of Bacillariophyceae) occurred on November 12. Anabaena planctonica, Anabaena sp., Microcystis aeruginosa, Oscillatoria sp. of Cyanophyceae, Ankistrodesmus sp., Dictyospaerium pulchellum, Micractinium pusillum, Pediastrum simplex var. doudenarium, Staurastrum cingulum of Chlorophyceae and Ceratium hirundinella of Dinophyceae were observed by scanning electron microscopy.

달팽이관내 기저막의 유한요소 모델링

강희용,양성모,김봉철,임재중,용부중 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.1

Cochlea is well known to have the ability to analyze a wide frequency and this ability seems to be caused to the Basilar Membrane(BM) configuration. However, the relationship between the Cochlea frequency-position map is not clear. In this paper, the three-dimensional BM model was made using the Finite Element Method. Then, an attempt was made to examine the influence of the BM configuration on the Cochlea frequency-position map.

분해성 고분자를 이용한 지속성 비료에 관한 연구

장상희,신부영,조무환,이일희 嶺南大學校 環境問題硏究所 1997 環境硏究 Vol.16 No.2

요약문농작물에 사용된 비료중 30~705가 농작물의 영양분으로 이용되고, 나머지는 지표수 에 의하여 하천으로 유입되거나, 지하수로 스며든다. 이러한 이유로 경제적 손실과 더불어 지하수에 질소 성분이 농축되어 식수 오염에 큰 영향을 미친다. 본 연구에서는 고분자 가공 기술을 응용하여 120。C에서 무정형 폴리 프로필렌과 요소비료를 혼합하여 지속성 비료 제 조를 제조하였다. 제조된 지속성 비료는 25。C 수중에서 비료성분의 방출속도를 측정하였 다. AbstractIt is estimated that only 30∼70% of the fertilizer applied in agriculture is used for plant nutrition, the rest is carried away by ground water or lost through mtrification-denitrification. Apart from the economic loss due to wastage, severe environmental problems arise due to increasing nitrate concentration in public drinking water. The fertilizer urea was mixed with APP (atactic polypropylene) by super mixer at 120 'C. The rate of fertilizer release was determined by checking dissolution rate in water at 25。C.

완전 생분해성과 광분해성을 갖는 필름에 대한 연구

이상일,서석훈,홍경민,신용섭,장상희,신부영 영남대학교 공업기술연구소 2001 工業技術硏究所論文集 Vol.29 No.1

Bio-and-photodegradable polymer composites were prepared by blending biodegradable aliphatic polyester and photodegradable master batch(M/B). Photodegradability, biodegradability, thermal properties and mechanical properties were investigated. The biodegradability of EnPol(G4600) composites decreased wish increasing the amount of M/B, while that of EnPol(G8000) composites increased. Tensile strength and elongation decreased with increasing the time of outdoor exposure and the amount of M/B but modulus comparatively maintained. The mechenical properties decreased as the content of M/B increased, while the melting temperature unchanged.

제품생산자동화를 위한 로봇제어

남부희,이상재,이석원 강원대학교 석재복합신소재제품연구센터 1996 석재연 논문집 Vol.1 No.-

본 연구에서 신경망 회로를 이용하여 토크계산제어기를 갖는 로봇 매니퓰레이터의 비선형성과 불확실성을 보상하는 제어기를 설계한다. 여기서 사용한 신경망 회로는 앞되먹임구조의 자율학습을 하는 제어기이며 Ishiguro등이 제안한 학습 데이터가 필요로 하는 감독학습 방법의 보상기제어기 구조보다 간단하다. In this research we research the controller using neural network to compensate for the nonlinearities and uncertainties of the robotic manipulators with the computed torque method. This neural network is used as the feed forward controller which is trained on-line by unsupervised learning and is simpler in the control scheme than the neural network controller proposed by Ishiguro et al. which needs the teaching signals of the neural network compensators and whose learning is supervised.