국제환경탐구올림피아드 참가 방안에 관한 연구

이현욱,심규철,임영득,정구흥,장남기 韓國生物敎育學會 1997 생물교육 Vol.25 No.2

The purpose of this study is to establish the strategies for participating in International Environmental Project Olympiad(INEPO). The aims of INEPO are to improve the environmental conscious of the students, to get the students cope with the environmental problem with the permanent and positive attitudes. In the projects the evaluation will be made according to scientific and economic existence, practicability and productivity etc. For the participation of our country in INEPO, the students who will be participated in INEPO must be selected by the Korean Environmental Project Olympiad(KEPO). For this goal, the Commitee of Korean Environmental Project Olympiad must be organized. Educational effects through holding of KEPO and participating in INEPO are to increase the capability of environmental problem of our country through international exchange, to find talented students in this area. to activate environment education and to contribute to national economy and environment conservation by practicing the products.

중국 조선족의 인구이동 패턴과 중국 연안도시의 역동적 변화

이현욱 한국문화역사지리학회 2014 한국문화역사지리학회 학술대회 자료집 Vol.2014 No.1

비대칭 오류 비용을 고려한 SVM 기반 지능형 침입탐지모형 개발

이현욱,안현철 한국지능정보시스템학회 2011 한국지능정보시스템학회 학술대회논문집 Vol.2011 No.5

최근 인터넷 사용의 증가에 따라 네트워크에 연결된 시스템에 대한 악의적인 해킹과 침입이 빈번하게 발생하고 있으며, 각종 시스템을 운영하는 정부기관, 관공서, 기업 등에서는 이러한 해킹 및 침입에 의해 치명적인 타격을 입을 수 있는 상황에 놓여 있다. 이에 따라 인가되지 않았거나 비정상적인 활동들을 탐지, 식별하여 적절하게 대응하는 침입탐지 시스템에 대한 관심과 수요가 높아지고 있으며, 침입탐지시스템의 예측성능을 개선하려는 연구 또한 활발하게 이루어지고 있다. 본 연구 역시 침입탐지시스템의 예측성능을 개선하기 위한 새로운 지능형 침입탐지모형을 제안한다. 본 연구의 제안모형은 비교적 높은 예측력을 나타내면서 동시에 일반화 능력이 우수한 것으로 알려진 Support Vector Machine(SVM)을 기반으로, 비대칭 오류비용을 함께 고려하여 침입을 효과적으로 차단할 수 있도록 설계되었다. 제안모형의 우수성을 확인하기 위해, 기존 기법인 로지스틱 회귀분석, 의사결정나무, 인공신경망과의 결과를 비교하였으며 그 결과 제안하는 SVM 모형이 다른 기법에 비해 상대적으로 우수한 성과를 보임을 확인할 수 있었다.

비기주식물(非寄主植物)의 전(前),혼작(混作)에 의(依)한 고추역병(疫病) 억제효과(抑制效果)

이현욱,김충회,이은종 한국식물병리학회 1990 Plant Pathology Journal Vol.6 No.4

작부체계(作付體系)에 의(依)한 고추역병(疫病) 발생억제(發生抑制)

이현욱,김충헌,남기웅 한국식물병리학회 1991 Plant Pathology Journal Vol.7 No.3

평면회로 기법에 의한 SIW Cavity 공진기를 이용한 X-밴드 발진기

이현욱,이종철,이일우,남희 한국ITS학회 2008 한국ITS학회논문지 Vol.7 No.1

The substrate integrated waveguide (SIW) structure can be approximated as the rectangular waveguide using common dielectric substrate with via-holes. To realize reflection-type resonator, 50-Ω microstrip line can be used for coupling with the center plane of the cavity. The oscillator is designed to operate at 9.45 GHz using the reflection-type SIW cavity resonator. The phase noise of oscillator shows -98.1 dBc/Hz at 100 KHz offset. In experiment, the reflection type SIW cavity resonator improves the loaded quality factor making the low phase noise oscillator possible. Due to the entirely planar structure of this resonator, this technique can also be adequate in oscillator applications for a low cost and low phase noise performance. SIW (Substrate Integrated Waveguide) cavity 공진기의 구조는 유전체기판에 다수의 via-hole 을 이용함으로써 나타낼 수 있으며, rectangular waveguide 와 유사한 특성을 갖는다. 그리고 50-Ω 마이크로스트립라인과 SIW cavity 공진기 중앙간의 결합구조를 통하여 대역저지 특성이 나타나도록 하였다. 이러한 특성을 갖는 SIW cavity 공진기를 이용하여 X-band(9.45 GHz) 발진기를 제작하였고, 위상잡음은 100 kHz offset에서 -98.1 dBc/Hz 로 측정되었다. SIW cavity 공진기는 높은 QL 값을 갖고, 2차원 구조이기 때문에 저비용에 우수한 위상잡음 특성을 갖는 발진기 설계에 응용할 수 있다.

선반가공공정에서 RSM을 이용한 가공공정의 포괄적 최적화

이현욱,권원태,Lee, Hyun-Wook,Kwon, Won-Tae 한국생산제조학회 2010 한국생산제조학회지 Vol.25 No.3

Optimization of the turning process has been concentrated on the selection of the optimal cutting parameters, such as cutting speed, feed rate and depth of cut. However, optimization of the cutting parameters does not necessarily guarantee the maximum profit. For the maximization of the profit, parameters other than cutting parameters have to be taken care of. In this study, 8 price-related parameters were considered to maximize the profit of the product. Regression equations obtained from RSM technique to relate the cutting parameters and maximum cutting volume with a given insert were used. The experiments with four combinations of cutting inserts and material were executed to compare the results that made the profit and cutting volume maximized. The results showed that the cutting parameters for volume and profit maximization were totally different. Contrary to our intuition, global optimization was achieved when the number of inserts change was larger than those for volume maximization. It is attributed to the faster cutting velocity, which decreases processing time and increasing the number of tool used and the total tool changing time.

심폐소생술에서 아트로핀은 필요한가?

이현욱,박득현,윤유상,김양원,이준엽,박경혜,권인호,여운형,박하영,조준호 대한응급의학회 2014 大韓應急醫學會誌 Vol.25 No.5

Purpose: According to the 2010 guidelines for cardiopulmonary resuscitation (CPR) of the American Heart association, administration of atropine for non-shockable rhythm is no longer recommended, however, there are insufficient data in humans. This study was conducted to evaluate the results of CPR, whether the combined administration of atropine and epinephrine (Atropine combined group, AG) compared with epinephrine only injection (epinephrine only group, EG) for patients with non-shockable rhythm. Methods: A total of 449 patients who underwent CPR in the emergency department from 2009 to 2012 were included. Retrospective analysis was performed according to atropine administration during CPR. We investigated Return of Spontaneous Circulation (ROSC), sustained ROSC, 30-day survival, and 30-day neurological outcome using Utstein templates. Results: There were 178 (48.9%) patients in the AG. There were no significant differences in the baseline characteristics. The two groups had similar rates of ROSC, sustained ROSC, and 30-day survival. However, AG had a significantly poor neurological outcome compared to EG, with an adjusted odds ratio of 0.074 (95% CI 0.012-0.452, p=0.005). Conclusion: The combination therapy of atropine and epinephrine during CPR showed poor neurological outcome compared with epinephrine alone. Atropine is not useful for adults with non-shockable rhythm in terms of 30-day neurological outcome. The two groups had similar rates of ROSC, sustainedROSC, and 30-day survival. However, AG had a significantlypoor neurological outcome compared to EG, with anadjusted odds ratio of 0.074 (95% CI 0.012-0.452, p=0.005). Conclusion: The combination therapy of atropine and epinephrineduring CPR showed poor neurological outcomecompared with epinephrine alone. Atropine is not useful foradults with non-shockable rhythm in terms of 30-day neurologicaloutcome. Purpose: According to the 2010 guidelines for cardiopulmonary resuscitation (CPR) of the American Heart association, administration of atropine for non-shockable rhythm is no longer recommended, however, there are insufficient data in humans. This study was conducted to evaluate the results of CPR, whether the combined administration of atropine and epinephrine (Atropine combined group, AG) compared with epinephrine only injection (epinephrine only group, EG) for patients with non-shockable rhythm. Methods: A total of 449 patients who underwent CPR in the emergency department from 2009 to 2012 were included. Retrospective analysis was performed according to atropine administration during CPR. We investigated Return of Spontaneous Circulation (ROSC), sustained ROSC, 30-day survival, and 30-day neurological outcome using Utstein templates. Results: There were 178 (48.9%) patients in the AG. There were no significant differences in the baseline characteristics. The two groups had similar rates of ROSC, sustained ROSC, and 30-day survival. However, AG had a significantly poor neurological outcome compared to EG, with an adjusted odds ratio of 0.074 (95% CI 0.012-0.452, p=0.005). Conclusion: The combination therapy of atropine and epinephrine during CPR showed poor neurological outcome compared with epinephrine alone. Atropine is not useful for adults with non-shockable rhythm in terms of 30-day neurological outcome.

フ一ドデザ一卜問題: 無연社會が生む"食砂漠" (푸드사막화 문제)

이현욱 한국도시지리학회 2013 한국도시지리학회지 Vol.16 No.2

국제생물올림피아드 참가 방안에 관한 연구

이현욱,심규철,목창수,박인근,장남기 韓國生物敎育學會 1997 생물교육 Vol.25 No.2

The purpose of this study is to establish the strategies for participating in International Biology Olympiad(IBO). This study was conducted to investigate the membership and the successive results of IBO, to analyze the contents of competition. The aims of IBO are to encourage gifted students, to expand their talents and to promote their career as a scientist. The competition consists of two part, theoretical and practical examinations. China, Czech and Poland have acquired better fruits than others in successive olympiads. For the participation of our country in IBO, the students who will be participated in IBO must be selected by the Korean Biology Olympiad(KBO). Far this goal, the Commitee of Korean Biology Olympiad must be organized. Educational effects through holding of KBO and participating in IBO are to find the gifted students in biology, to activate biology education much more and to utilize the results of Olympiad as the important informations on biology education policy.