Hollow-Fiber LPME를 이용한 잔류농약 검출

조현우,이상섭,신윤지,장미애 경기대학교 기초과학연구소 2008 기초과학논문집 Vol.21 No.-

A method for the determination of trace amount of pesticides in aqueous samples using hollow fiber-liquid phase microextraction(HF-LPME) and capillary gas chromatograph/micro electron capture detector(GC/μ ECD) has been established. HF-LPME method has been optimized with respect to several experimental parameters including the effects of extraction solvent, extraction time and extraction temperature for the determination of pesticides from aqueous samples. The calibration curves for pesticides showed good linearity (above r²=0.98). The established method is feasible for the determination of trace amounts of pesticides in several aqueous sample. The limit of detection(LOD) and the limit of quantitation(LOQ) have been found to be 0.05~1.0 and 0.5~2.5 ng/mL, respectively. The established HF-LPME method for the analysis of pesticides from aqueous sample can be used for the determination of biological, food and environmental samples.

건축공사시방서에서의 KS규격의 국제인증방안에 관한 연구

김경식,이재섭,김용수,이규진,조용훈,최완철,전재열,이현수,구재동,이기환 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1

The purpose of this research is make out construction specifications for International Construction. Using off-shore products incur cost increase and longer delivery term of construction. and inconvenient on International Construction. Expand the range of additional local products conforming to performance. Life Cycle Cost. maintainability. operability. user's acceptability, etc.. And this study is suggest the standard formats and the techniques for construction specification.

일개 자동차 부품공장 근로자에서 초음파로 측정한 수근관 형태와 수근관증후군 위험도

김덕수,정해관,임현술,권용욱,이종민,조대현,최대섭 大韓産業醫學會 2002 대한직업환경의학회지 Vol.14 No.3

목적 : 일개 사업장의 생산직 근로자를 대상으로 손목 계측치 및 초음파를 이용한 수근관 계측치의 상관성 분석을 통하여 수근관증후군 발생에 관여하는 개인의 감수성 및 위험요인을 파악하여 생산직 근로자들의 수근관증후군 예방에 활용하고자 본 연구를 수행하였다. 방법 : 경주시에 위치한 자동차 방음재를 생산하는 사업장에 생산직 근로자 남자 24명, 여자 11명 등 총 35명을 대상으로 2000녀 4월과 2000년 10월 반드시 각 설문조사, 이학적검사, 전기진단검사를 실시하였으며, 2000년 10월에는 초음파를 이용한 수근관계측도 실시하였다. 결과 : 수근관증후군의 신체계측 요인에 따른 분석에서는 수근관 전치/폭 비가 0.17 미만인 군에 비하여 0.17 이상인 군에서 통계적으로 유의하게 높았다(p<0.05). 총 수근관 면적(두께×폭)은 300 ㎟이상인 군에 비하여 300㎟ 미만인 군에서 통계적으로 유의하게 높았다(p<0.05). 성별을 통제변수로 처리한 신체 계측치간 상간 분석에서는 수근관폭은 전기진단 검사와 음의 상관성을 보였으며, 수근관 두께는 전기진단 검사와 양의 상관성을 보였다. 수근관 두께/폭 비는 전기진단 검사와 양이 상관성을 보였으며, 수근관비 전치/두께 비는 전기진단 검사 결과와 음의 상관성을 보였다. 하부 수근관 면적[폭×(두께-전치)]은 전기진단 검사와 양의 상관성을 보였으며, 상부 수근관 면적(폭×전치)은 전기진단 검사와 음의 상관성을 보였다. 또한 수근관 전치의 상대적 비가 클수록 수근관증후군의 회복이 유의하게 좋았다. 결론 : 수근관증후군은 수근관 폭이 좁을수록, 수근관 두께가 두꺼울수록, 수근관 전치가 작을수록 수근관증후군 위험도가 증가한다. 저자들은 초음파를 이용한 수근관 형태의 측정은 수근관증후군의 발생의 내적 요인에 대한 중요한 정보를 제공하면 수근관증후군 발생 및 회복의 개별적 위험요인을 예측하는데 중요한 근거를 제공하는 것으로 판단하였다. Objectives: This study was conducted to evaluate individual susceptibility to carpal tunnel syndrome (CTS) by ultrasonographic measurement of the carpal tunnel configuration in workers doing repetitive work. Methods: The study subjects consisted of 24 male and 11 female workers in a soundproof material manufacturing company in Gyeongju. We conducted a self-reported questionnaire survey, a physical examination and an electrodiagnostic study (EDS) in April 2000. After the examination, jobs were rearranged for workers with CTS. A follow up physical examination. EDS, and measurement of the carpal tunnel by ultrasonography was done six monsths later. Results: Of those studied. prevalence or CTS was 63.6/100 persons among women and 29.2/100 persons among men. Mean depth and width of wrist was shorter in those with CTS compareal to the controls (p<0.05). The risk of CTS was higher in workers whose carpal tunnel ratio (displacement/width) was 0.17 or higher (OR 7.13, 95% confidence interval 1.18-43.1), and in workers whose carpal tunnel area was less than 300 ㎟ (OR 8.00, 95% confidence interval 1.18-68.5). Carpal tunnel depth and depth/width ratio had a positive correlation with motor latency of the median nerve and median-ulnar sensory latency difference (p<0.05). whereas the carpal tunnel width. displacement/depth ratio, and area (width×displacement) had a negative correlation with median nerve latencies after adjusting for gender. Workers who showed an improvement in the clinical stage of CTS after job rearrangement had a significantly lower carpal tunnel displacement/width ratio and displacement/depth ratio. They also had smaller upper carpal tunnel area (width×displacement) and larger upper carpal tunner\l area [(depth-displacement)×width] than the controls (p<0.05). Conclusions:Ultrasonographic measurement of the carpal tunnel is a good predictor of susceptibility and prognosis of CTS in workers doing repetivive work.

황 첨착 활성탄에 의한 구리제거

김영환,박정훈,김정섭,유현철,이봉섭,곽명화,우성훈,박승조 東亞大學校 環境問題硏究所 2005 硏究報告 Vol.27 No.1

This study was carried out to remove copper ion in case of activated carbon impregnated sulphur(ACS) dose and different pH using activated carbon impregnated sulphur that prepared from activated carbon at sulphur dioxide atmosphere. Removal copper ion concentration was increased as increasing the ACS dose when copper ion concentration was 10 mg/L. Optimum dose of ACS 13.3 g ACS/L and maximum removal efficiency was 93%. The results obtained from adsorption experiment in the condition of ACS optimum dose when the pH was 3, 4, 5 respectively was pH 5 was excellent.

골분을 이용한 구리 흡착 첨착

김은정,박정훈,김정섭,유현철,이봉섭,곽명화,우성훈,박승조 東亞大學校 環境問題硏究所 2005 硏究報告 Vol.27 No.1

Spent pig bone was consist of hydroxyapatite. And then we thought that it have a possibility as a adsorbent. The preparation of bone char prepared from spent pig bone in this study. We study on the recycling possibility as a adsorbent is able to adsorb copper ion from their single aqueous solutions. The results are summarized as follows. Bone char that prepared from spent pig bone at 105, 400, 700℃. The adsorption removal efficiency of copper ion onto bone char as adsorbent was above 90% for 15 hours. Increase in the initial pH of the copper ion solution result in an increase in the copper ion uptake per unit weight of the adsorbent. Freundlich isotherm model was found to be applicable for the experiment data of copper ion. The results showed that spent pig bone can be used for the absorption of the copper ion.

Dynamic Neural Units and Genetic Algorithms With Applications to the Control of Unknown Nonlinear Systems (pp.1943-1944)

Hyun-Seob Cho(조현섭),Jin-Kyoung Min(민진경),Yong-Gi Roh(노용기),Byung-Jo Jung(정병조),Sung-Whan Jang(장성환) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.7

"Dynamic Neural Unit"(DNU) based upon the topology of a reverberating circuit in a neuronal pool of the central nervous system. In this thesis, we present a genetic DNU-control scheme for unknown nonlinear systems. Our methodis different from those using supervised learning algorithms, such as the backpropagation (BP) algorithm, that needs training information in each step. The contributions of this thesis are the new approach to constructing neural network architecture and its trainin

A Study on Adaptive Control of Nonlinear Dynamic Systems using Neural network Evolutionary Algorithm

Hyun-Seob Cho,Ho-Ik Jun,Man-Oh Kim 보안공학연구지원센터 2013 International Journal of Control and Automation Vol.6 No.6

A Video Retrieval System for Electric Safety Education based on Mobile Agent

Hyun-Seob Cho(조현섭),Keun-Wang Lee(이근왕),Hee-Sook Kim(김희숙) 대한전기학회 2005 대한전기학회 학술대회 논문집 Vol.2005 No.7

Study on Properties of Piezoelectric Ceramic Transformers

Hyun-Seob Cho(조현섭),In-Ho Ryu(유인호) 한국산학기술학회 2009 한국산학기술학회논문지 Vol.10 No.10

본 논문은 압전 세라믹 변압기(PT)의 특징과 회로 설계를 제시하였다. 그리고 회로 요소로써 사용하는 PT는 인버터 설계의 일반적인 접근법을 보여주기 위한 것이다. 또한 압전기 영향의 기술(記述)은 다수의 연구에서 복잡한 방정식과 공식도 쉽게 찾을 수 있다. 특히 압전기 세라믹 EMT가 변화하지 않으며 PT기초 전기소자의 여러 가지 예 는 더욱 효과적인 PT의 강점을 이용하는데 도움이 될 것이다. In this paper, it is reviewed is to acquaint a circuit design with features of piezoelectric ceramic transformers(PT) and to show the general approach to the design of inverters utilizing PT as a circuit element. The description of the piezoelectric effect is not present here and can be easily found in numerous publications as well as complex equations and formulae. What is the most important to understand is that "they are different" –one cannot just change an electromagnetic transformer (EMT) for a piezoelectric one. Several examples of PT-based circuitry will help to start and use PT’s advantages most effectively.

A Study on Optimized Adaptive Control of Nonlinear Plants Using Neural Network

Hyun-Seob Cho(조현섭),Yong-Gi Roh(노용기),Sung-Whan Jang(장성환) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.7

In this paper, a direct controller for nonlinear plants using a neural network is presented. The controller is composed of an approximate controller and a neural network auxiliary controller. The approximate controller gives the rough control and the neural network controller gives the complementary signal to further reduce the output tracking error. This method does not put too much restriction on the type of nonlinear plant to be controlled. In this method, a RBF neural network is trained and the system has a stable performance for the inputs it has been trained for. Simulation results show that it is very effective and can realize a satisfactory control of the nonlinear system.