개방 EDI의 보안 서비스 모델에 관한 연구

주해종,안익수,김길준 聖潔大學校 自然科學硏究所 1996 自然科學硏究 Vol.1 No.-

기업간 전자문서교환이라고 불리우는 EDI(Electronic Data Interchange)는 90년대에 들어서면서 모든 부문에 걸쳐서 주목 받고 있으며, 여러 국제 표준화 기구들이 EDI에 관련된 각종표준 제정에 노력하고 있다. 특히, 무역, 유통, 운송 등 각 분야에서 EDI 시스템의 도입이 필수적인 현 시점에서 정보 전송시의 정보 보호가 가장 중요한 문제로 대두되고 있다. 본 논문에서는 개방형 시스템에 적합한 개방 EDI 보안 구조 모델을 제시하였고 EDI위협 요소에 대한 보안 서비스중 몇 가지를 선정하여 그 기법을 분석하여 구현하였다.

DCT 부호화 영상의 비트 선택적 에러정정부호 적용

주언경,蔡鍾吉 慶北大學校 1992 論文集 Vol.52 No.-

DCT coding, using energy compaction and decorrelation by transform, is proved to be efficient in the absence of channel error, but its performance degrades rapidly over noisy channel. In this paper, bit selective error correction coding technique is presented for protecting DCT coefficients over noisy channel. Since each bit transmitted in a block has different error sensitivity, bit error sensitivity is computed and analyzed for various binary codes, images and DCT block sizes. Then the bits with higher error sensitivity are selected to be protected by BCH error correction codes. As a result, without increasing transmission bits, PSNR can be improved up to 8-10dB and the image with improved quality is reconstructed.

QMF를 이용한 대역 압축 시스템에서의 스크램블링 효과

주언경,蔡鍾吉 慶北大學校 1992 論文集 Vol.52 No.-

Scrambling has been used as a method to encrypt the transmission signal for purpose of service protection from illegal use of unauthorized subscribers in Conditional Access system. More recently it is proposed to be used in a HDTV system such as MIT-CC in order to turn ghost, correlated noise, to uncorrelated white noise. In this paper, band rotation scrambling method using a modified line rotation is proposed for the band-compressed system using QMF. And scrambling effects on conversion of ghost to white noise and service protection are studied and analyzed. As results, effects of whitening ghost and service protection by the proposed method are shown to be superior to the existing line rotation method.

이동형 생체계측을 위한 임베디드 컴퓨팅

홍주현,진계환,박경순,조명찬,박길선,차은종,이태수 충북대학교 의과대학 충북대학교 의학연구소 2003 忠北醫大學術誌 Vol.13 No.2

연구목적: 초소형 정밀 기계 기술로 제작된 2차원 가속도 센서와 916 MH2 단거리 고주파 데이터 통신 기술을 응용하여 인체의 운동상태를 자동으로 감지하고 분류하는 기법을 제안 하고자 하였다. 재료 및 방법: 인체의 신호를 획득하기 위하여 미국 버클리대에서 제작한 무선 센서를 등 산용 조끼의 전면상단에 부착해서, 대상자의 흉골 부위에 위치하도록 하고, 앉은 상태에서 일어서거나 눕거나 하는 동작 및 그 역동작이 일어날 때, 가속도 센서에서 감지되는 4가지 종류의 파형 현화에 해당되는 데이터를 무선센서 네트웍을 통해 획득하였다. 결과: 획득한 신호를 주성분분석(Principal Component Analysis)과 지원벡터머신(Support Vector Machine)을 사용하여, 2차주성분까지를 도표화하고 클러스터링 함으로써, 4개의 영역으로 분할하는 것이 가능함을 말 수 있었다 결론: 소형 센서들이 작동되는 임베디드 컴퓨팅 환경에서 일상생활 중에 발생하는 인체의 4가지 동작을 자동으로 감지하고 분류하는 것이 가능함을 보였다. Purpose: New monitoring and classifying method of human motion contort was pro- posed by using 2-axial MEMS accelerometer and 916 MHz short-range data communica-tion technology. Materials and Methods: The wireless sensor of MICA mote was attached to a woman mountain vest and located close to the subject's sternum. During four types of sub-ject's motion, that is, sit-to-stand, stand-to-sit, sit-to-tying, and tying-to-sit, waveform changes of the accelerometer data were acquired by wireless sensor network. Results: The acquired signal was analyzed by Principal Component Analysis(PCA) and Support Vector Machine(SVM) technique. By clustering the first and second principal components, four regions corresponding to the four types of motion, were clearly segment-ed. Conclusion: Human motion context during daily life could be monitored and classified automatically by using small sensors in embedded computing environment

연안 도시 대기오염 물질의 농도분포 특성

박종길,석경하,김지형,차주완 한국환경과학회 2002 한국환경과학회지 Vol.11 No.12

This paper aims to find the characteristics of concentration distribution of coastal urban air pollutants. For this purpose, It was used the daily meteorological data and hourly concentration data O_3 and NO_2 in Busan metropolitan city from 1994 to 1996. It was investigated the annual and monthly distribution of ozone and nitrogen dioxide concentration at each site in Busan, and also investigated the characteristics of concentration change of air pollutants with time under the sea breeze. As a results, the concentration of nitrogen dioxide and ozone tend to be increased every year and nitrogen dioxide concentration is higher than ozone concentration at all site in Busan. The concentration of ozone is high in summer season and low in winter season, but the concentration of nitrogen dioxide have a reversed trend. The monthly peak concentration of ozone occurred in April and September, while the monthly minimum concentration of nitrogen dioxide occurred in August. Their trend were indentified by sites near the coastline than sites stands apart from the coastline. The sea breeze occurred annual mean 81 days in Busan from 1994 to 1996. The main wind direction of sea breeze was classified into southeasterly. In case of southwesterly, It was pronounced the south wind and southwest wind. In case of southeasterly, the occurrence frequency of east wind was high. Especially, the concentration of urban air pollutants, such as ozone and nitrogen dioxide, were high on time which the sea breeze flow, and the areas that ozone concentration was high moved from outside part to central part of city with time. In costal urban such as Busan, the wind direction of sea breeze is influenced the influenced the change of ozone and nitrogen dioxide concentration on time which the sea breeze flow at each site and air pollutants concentration of sites on the pathway of sea breeze.

광주기변화가 초파이의 우화리듬에 미치는 영향

송기덕,추종길,한영주 高神大學校 1987 論文集 Vol.15 No.-

An examination was carried out with Drosophila melanogaster to analyze the genetic effect of different photoperiod on the mean eclsion time and eclosion rhythm. 1. The mean eclosion time in accordance with changes of photoperiod showed the high speed under the situation of LL (constant light). The eclosion phae of strain managed under LD (periodical light and dark) developed the clear rhythm of eclsion restricted in dark time and realized in light time. The synchronization of its rhythm was most strongly realized right upon the illumination. 2. The mean eclsion time (hours) of five region of natural populations was ranged from 206.6 hours (cheju) to 217.3 hours (Anyang). The eclosion time under LL as faster than DD and LD and male was faster than female. 3. From these resuts, eclsion rhythm in D. melanogaster was synchronized by the circadian cycle under the periodical light and dark environment (12L : 12D).

향류분배 장치에 의한 주광성 행동의 인위도태와 자연도태의 유전적 효과

추종길,한영주,임귀순 中央大學校 自然科學硏究所 1987 自然科學硏究所 論文集 Vol.1 No.-

Directional selections for positive and negative phototaxis were carried out with hte populations, derived from Jeju and L-F strain of Drosophila melanogaster, using the countercurrent distribution apparatus. Effects of selection for positive and negative phototaxis were clearly recognized in the early generations, and the populations were reached a selection plateau from the 5th generation onwards. After 9 generations of artificial selection, the populations selected for positive and negative phototaxis were relaxed in the following 16 generations. The phototactic responses to natural selection of positive and negative populations were not returned to their neutral states. As a result of artificial and natural selection, genes of phototactic behaviors measured by means of countercurrent distribution apparatus are possibly controlled by major genes, and they seem to be fixed in the early generations of artificial selection. Walking behavior in populations of flies with positive and negative phototactic respones at the 9th, 16th and 17th generations was measured by the connected test tube apparatus. The negative populations turned out slow walking behavior. It seems reasonable to assume that genes controlling negative phototaxis and slow walking behavior were accumulated and selected within populations simultaneously.

정신분열병 환자에서 Haloperidol이 99m-Tc-ECD SPECT로 측정한 국소뇌혈류량에 미치는 영향

천근아,이종두,민성길,김세주,안석균 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.4

연구목적 : 정신분열병 환자에서의 뇌혈류량은 약리학적 상태를 포함한 다양한 요소들에 의하여 영향을 받는다. 항정신병약물이 국소뇌혈류량에 미치는 영향에 관한 많은 연구가 행해져 왔으나 항정신병약물의 종류와 노출기간, 약물용량의 차이로 인해 다양하고도 상반된 결과를 보여왔다. 따라서 본 연구에서는 정신분열병 환자에서 항정신병약물의 종류와 노출기간을 통제한 상태에서 약물 투여시 국소뇌혈류량의 변화를 관찰하고자 하였다. 방 법 : 항정신병약물 비노출(antipsychotic drug-naive) 정신분열병 환자 18명과 haloperidol을 투여받은 환자 19명을 대상으로 안정 상태(resting state)에서 SPECT를 촬영하여 국소뇌혈류량을 측정한 후 두군 사이의 상대적 뇌혈류량을 비교하였다. Haloperidol은 D2 수용체에 비교적 선택적으로 작용하고 활성대사산물이 적기 때문에 실험약물로 선택되었고 약물노출기간은 1∼3주동안으로 제한하였다. 결 과 : 우측 저측두엽, 좌측 저전두엽, 좌·우측 기저신경절, 좌측 시상에서의 상대적 평균 혈류지표는 halo-peridol 투여군에서 비노출군에 비해 유의하게 증가되어 있었다. 또한 좌·우측 두정-후두엽과 우측 두정엽에서의 상대적 평균 혈류지표도 haloperidol 투여군에서 비노출군에 비해 유의하게 증가되어 있었다. 반면 좌측 저측두엽의 상대적 평균 혈류지표는 haloperidol 투여군에서 항정신병약물 비노출군에 비해 유의하게 감소되어 있었다. 그러나 우측 저전두엽, 우측 시상, 좌·우측 고측두엽, 좌·우측 고전두엽, 좌측 두정엽에서 두 군 사이의 상대적 평균 혈류지표는 유의한 차이를 보이지 않았다. 결 론 : 정신분열병 환자에서 항정신병약물이 국소뇌혈류량에 영향을 미치며, 항정신병약물 투여상태가 뇌혈류량 측정시 고려되어야할 중요한 변수임을 시사한다. Objectives : Regional cerebral blood flow(rCBF) in schizophrenics is confounded by various factors including medication status. Previously, there have been numerous studies regarding the effects of antipsychotics on rCBF. However, these works have shown contradictory and inconsistent findings due to the different of type, dose and exposed duration of antipsychotics. The aim of this study was to observe the effect of antipsychotic medication on rCBF and exposed duration of antipsychotics under control. Methods : Eighteen drug-naive schizophrenics and 19 schizophrenics medicated with halo-peridol were included in the study. Regional cerebral blood flow was assessed with single-photon emission computed tomography(SPECT) under a resting state. Relative rCBF was compared between two groups. Haloperidol was selected as the antipsychotic drug as it has relatively selective action at the D2 receptor and less active metabolites. Exposed duration was limited from one to three weeks. Results : Haloperidol-medicated schizophrenic patients had a significantly greater increase of relative cerebral perfusion in the right inferior temporal lobe, left inferior frontal lobe, both basal ganglia, left thalamus, both parieto-occipital lobes, and right parietal lobe than drug-naive schizophrenic patients. Haloperidol-medicated schizophrenic patients had a significant decrease of relative cerebral perfusion in left inferior temporal lobe. However, no significant differences in relative rCBF were found between drug-naive and haloperidol-medicated schizophrenic patients in right inferior frontal lobe, right thalamus, both superior temporal lobes, both superior frontal lobes, and left parietal lobe. Conclusion : These findings suggest that antipsychotics affect regional cerebral blood flow, and antipsychotic medication status must be considered in the relative rCBF studies of schizophrenic patients.

QT연장 증후군 환자에서 Head-Up Tilt Test에 의해 유발된 Torsades De Pointes 1례

전익수,차태준,김길수,김동완,김규종,김찬욱,김성만,주승재,이재우 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.8

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.