DC 배전용 3상 AC/DC 컨버터의 병렬 운전시 발생하는 순환전류 제어 알고리즘

정철호(Chul-Ho Jung),신수철(Soo-Cheol Shin),정태복(Tae-Bok Jung),이택기(Taeck-Kie Lee),원충연(Chung-Yuen Won) 전력전자학회 2011 전력전자학술대회 논문집 Vol.2011 No.11

주의력결핍 과잉행동장애 아동과 정상 아동의 지능, 기억 및 전두엽 관리 기능에 대한 비교 연구

정철호(Chul-Ho Jung),류설영(Seol-Young Ryu),김희철(Hee-Cheol Kim) 대한생물치료정신의학회 2007 생물치료정신의학 Vol.13 No.2

Objectives:We aimed to prove that disinhibition in children with ADHD affects other cognitive function and learning achievement by comparing the intelligence, memory and frontal-executive function between children with ADHD and normal children. Methods:Twenty children with ADHD and nineteen normal children were sampled, their age range was 7 to 14. They were assessed using Conners scale, K-WISC-Ⅲ, Rey-Kim Memory test for children, Kims Frontal-Executive Function Neuropsychological Test. Results:There were no significant differences between children with ADHD and normal children in scores of total intelligence, VIQ, PIQ, VCI, POI and FDI in K-WISC-Ⅲ. However, children with ADHD showed lower memory function, especially delayed recall, visual immediate recall, visual delayed recall and memory retention compared to those of normal children. It might be assumed that lower memory function in children with ADHD is affected by retention among memory process(registration-retention-retrieval). And children with ADHD showed poor EIQ, interference index, word fluency/information DI, and FIQ/EIQ DI compared to normal children. Conclusion:Children with ADHD show poor memory function, especially retention and frontal-executive function, especially interference inhibition and word fluency compared to normal children, although there are no significant differences on measures of intelligence in children with ADHD and normal children. These results suggest that it need to train for children with ADHD to use frontal-executive function, especially behavioral inhibition to enhance the ability and skill of learning.

연마 방법과 칫솔질이 아크릴릭 레진의 표면 거칠기에 미치는 영향

이주리,정철호,최정한,황재웅,이동환,Lee, Ju-Ri,Jeong, Cheol-Ho,Choi, Jung-Han,Hwang, Jae-Woong,Lee, Dong-Hwan 대한치과보철학회 2010 대한치과보철학회지 Vol.48 No.4

연구 목적: 본 연구는 연마 술식에 따른 polymethyl methacrylate (PMMA)의 표면 거칠기의 차이를 비교하고, 광중합 광택제가 PMMA의 표면 거칠기에 주는 영향과 이후 칫솔질에 의한 거칠기의 변화를 알아보는데 그 목적이 있다. 연구 재료 및 방법: 총 60개의 $10{\times}10{\times}5\;mm$ 크기의PMMA 시편을 만들었다. 중합 방법 (압력 하 중합과 대기압 하 중합)과 표면 연마 방법 (기계적 연마와 화학적 연마)에 따라 대조군을 포함하여 각 10개씩 총 6군으로 나누었다. 기계적 연마는 카바이드 덴처버로 표면 마무리 한 후, 러버 포인트와 퍼미스를 이용하여 하였으며, 화학적 연마는 표면 마무리 후 광중합 광택제 ($Plaquit^{(R)}$; Dreve-Dentamid GMBH)를 도포하여 실시 하였다. 연마가 완료된 후 비 접촉식 3차원적 표면 형상 분석장치인 Accura $2000^{(R)}$으로 표면거칠기를 측정하였으며, 그 3차원적 영상을 얻었다. 그 후 칫솔질에 의한 마모의 영향을 평가하기 위해 초음파 전동 칫솔을 이용하여 각 시편당 칫솔질을 행하고 다시 Accura $2000^{(R)}$에 의한 표면 분석을 시행하였으며, 거칠기의 정도는 Ra 값으로 표시하였다. 연마 후와 칫솔질 후의 표면 거칠기를 비교하기 위한 통계적 분석은 Mann-Whitney test와 t-test를 이용하여 95% 유의수준에서 실시하였다. 결과: 화학적 연마군은 기계적 연마군에 비해 통계적으로 유의한 작은 평균 표면 거칠기 값을 보였으며 (P = .0045), 일반 대기압 하에서 중합시킨 군에서 그 차이가 더 크게 나타났다 (P = .0138). 초음파 전동 칫솔에 의한 모의 칫솔질 후 표면 거칠기는 기계적 연마군을 제외한 모든 군에서 크게 증가하였으며, 칫솔질 후의 표면 거칠기는 각 군에서 통계적으로 유의한 차이를 보이지 않았다. 결론: 비록 칫솔질에 의한 마모의 영향으로 표면 거칠기가 증가하기는 하지만, 화학적 연마가 기계적 연마에 비해 우수한 표면 거칠기를 보인다고 할 수 있다. Purpose: This study evaluated the effect of polishing techniques on surface roughness of polymethyl methacrylate (PMMA), as well as the influence of light-cured surface glaze and subsequent brushing on surface roughness. Materials and methods: A total of 60 PMMA specimens ($10{\times}10{\times}5\;mm$) were made and then divided into 6 groups of 10 each according to the polymerization methods (under pressure or atmosphere) and the surface polishing methods (mechanical or chemical polishing) including 2 control groups. The mechanical polishing was performed with the carbide denture bur, rubber points and then pumice and lathe wheel. The chemical polishing was performed by applying a light-cured surface glaze ($Plaquit^{(R)}$; Dreve-Dentamid GmbH). Accura $2000^{(R)}$, a non-contact, non-destructive, optical 3-dimensional surface analysis system, was used to measure the surface roughness (Ra) and 3-dimensional images were acquired. The surface roughness was again measured after ultrasonic tooth brushing in order to evaluate the influence of brushing on the surface roughness. The statistical analysis was performed with Mann-Whitney test and t-test using a 95% level of confidence. Results: The chemically polished group showed a statistically lower mean surface roughness in comparison to the mechanically polished group (P = .0045) and the specimens polymerized under the atmospheric pressure presented a more significant difference (P = .0138). After brushing, all of the groups, except the mechanically polished group, presented rougher surfaces and showed no statistically significant differences between groups. Conclusion: Although the surface roughness increased after brushing, the chemical polishing technique presented an improved surface condition in comparison to the mechanical polishing technique.

Clozapine에 의한 백혈구 및 호산구 증다증 1례

김희철(Hee-Cheol Kim),서영록(Young-Log Suh),박영남(Young-Nam Park),정철호(Cheol-Ho Chung),김정범(Jung-Bum Kim) 대한생물치료정신의학회 1997 생물치료정신의학 Vol.3 No.2

최근에 만성 난치성 정신분열병 환자에 대한 clozapine의 투여가 증가하면서 이 약물로 유발된 여러 가지 혈액학적 부작용이 많이 알려져 있으며 국내에서는 무과립구혈증과 혈소판 감소증이 증례로 보고되었다. 외국의 보고에 의하면 호산구 증다증이 비교적 빈번히 발생하고 호산구가 과립구 생성을 억제하여 백혈구 감소증을 초래할 수 있다고 제시된 바 있다. 저자들은 과거 알르지의 병력이 없는 만성 난치성 정신분열병 환자에게 clozapine을 투여하던 중 호산구 증다증이 발생하면서 뒤이어 백혈구 증다증이 나타났다가 clozapine 투여를 중지한 후에 혈구수가 점차적으로 정상화되었고 그후 clozapine을 재투여하면서는 혈액학적 이상소견이 없었던 환자 1례를 경험하였기에 문헌고찰과 더불어 보고하였다. Recently, the use of clozapine in patients with chronic refractory schizophrenia slowly increased and various hematological side effects of clozapine were found. The case of clozapine-induced agranulocytosis and thrombocytopenia was reported in domestic area. By the foreign reports, the clozapine-induced eosinophilia is relatively frequent and eosinophil may inhibit production of granulocyte. The authors reported one case of leukocytosis and eosinophilia associated with clozapine in chronic refractory schizophrenia. This case had no previous allergy history and was developed to leukocytosis following eosinophilia after clozapine ingestion. The leukocyte and eosinophil count were gradually normalized after discontinuation of clozapine administration and were continuously maintained normal level in spite of readministration of clozapine.

한국인 정신분열병 환자에서 항정신병 약물의 치료 반응과 도파민 D2, D3 및 D4 수용체 유전자 다형성

김희철,정성원,김대광,정철호,Kim, Hee-Cheol,Jung, Sung-Won,Kim, Dae-Kwang,Jung, Chul-Ho 대한생물정신의학회 2007 생물정신의학 Vol.14 No.3

항정신병 약물의 치료 반응을 예측해 줄 수 있는 유전자 지표를 찾기 위한 최근의 많은 약물유전학 연구들은 일관된 결과를 보고하지 못하고 있다. 본 연구는 항정신병 약물의 치료 반응과 도파민 D2, D3 및 D4 수용체 유전자 다형성과 관련성을 조사하였다. 연구 대상은 18~60세에 해당되면서 정신분열병의 DSM-IV 진단기준을 만족하고 본 연구에 대해 서면 동의한 국립부곡병원의 입원 환자 200명이었다. 연구는 대상자들의 입원 당시 병록지를 검토하여 후향적으로 이루어졌다. 대상자들은 퇴원할 당시를 기준으로 약물치료 반응 정도에 따라'반응군'과'비반응군'으로 구분되었으며 양군 사이의 도파민 수용체 유전자 다형성 차이를 비교하였다. 대상자 200명 중에서 188명(94%)이 비전형 항정신병 약물을 사용하였고 반응군은 141명(70.5%)이었다. 도파민 D2 수용체 유전자 Ser311Cys 다형성, 도파민 D3 수용체 유전자 Ser9Gly 다형성, 도파민 D4 수용체 유전자 exon III의 48개 염기반복 다형성에서 반응군과 비반응군 사이의 대립유전자 및 유전자형 빈도의 차이를 보이지 않았다. 결론적으로 본 연구에서는 항정신병 약물의 치료 반응과 도파민 D2 수용체 유전자 Ser311Cys 다형성, 도파민 D3 수용체 유전자 Ser9Gly 다형성, 그리고 도파민 D4 수용체 유전자 exon III의 48개 염기반복 다형 성과는 연관성이 없었다. 향후에는 단일의 항정신병 약물에 대한 전향적인 방법의 통제된 연구가 필요하다. Objectives:A considerable number of pharmacogenetic studies have been performed in recent years to define the association of antipsychotic drug response with dopamine receptor polymorphisms. The purpose of this study was to investigate the relationship between the therapeutic response to antipsychotic drugs and the polymorphisms of the dopamine D2, D3, and D4 receptor genes(DRD2, DRD3 and DRD4, respectively). Methods:We conducted retrospective chart review of 200 consecutively hospitalized patients with the diagnosis of schizophrenia(DSM-IV) who were treated with various antipsychotics(94% atypical antipsychotics) at Bugok National Hospital, Korea. The patients were divided into two groups, responders and non-responders, by responsiveness to antipsychotic drugs according to a four-point scale used in previous studies; responders included moderate to marked responded patients and non-responders included none to minimal responded patients. We analyzed the Ser311Cys polymorphism in the DRD2, the Ser9Gly polymorphism in the DRD3, and the exon III 48 bp repeat polymorphism in the DRD4. Results:Among the total patients of 200, 141(70.5%) were categorized as responders. There were no significant differences in the frequencies of the DRD2, DRD3, and DRD4 alleles and genotypes between responders and non-responders. Conclusion:These results suggest that the Ser311Cys polymorphism in the DRD2, the Ser9Gly polym- orphism in the DRD3, and the exon III 48bp repeat polymorphism in the DRD4 are not associated with the therapeutic response to antipsychotic drugs in Korean schizophrenic patients. A larger prospective study is needed to elucidate the association between antipsychotic response and dopamine receptor gene polymorphism.

빌딩용 DC 배전 시스템의 병렬 운전 시 발생하는 순환전류를 저감시키기 위한 제어 기법

김학성(Hack-Seong Kim),신수철(Soo-Cheol Shin),이희준(Hee-Jun Lee),정철호(Chul-Ho Jung),한동우(Dong-Woo Han),원충연(Chung-Yuen Won) 전력전자학회 2013 전력전자학회 논문지 Vol.18 No.3

DC 배전용 3상 AC/DC 컨버터의 병렬운전 시 발생하는 순환전류 저감 제어 기법

한동우(Dong-Woo Han),신수철(Soo-Cheol Shin),이희준(Hee-Jun Lee),정철호(Chul-Ho Jung),정태복(Tae-Bok Jung),원충연(Chung-Yuen Won) 전력전자학회 2012 전력전자학술대회 논문집 Vol.2012 No.7

조현병 환자에서 음성증상과 사회인지의 연관성

현지원(Jie Won Hyun),우정민(Jung Min Woo),정철호(Chul Ho Jung),김희철(Hee Cheol Kim),김양태(Yang Tae Kim) 대한생물치료정신의학회 2016 생물치료정신의학 Vol.22 No.2

Objectives:Although negative symptoms play important role in daily functioning of patients with schizophrenia, it remains unclear which symptoms clearly related to each other, and whether these symptoms develop sequentially or simultaneously. The current study examined negative and positive symptoms along with social cognition ability, to determine which symptoms are more strongly correlated. We also examined two subdomains of negative symptom, motivation/pleasure and expression, to investigate which subdomain has more strong correlation with social cognition. Methods:120 patients with schizophrenia were enrolled from three different hospitals. All patients were evaluated with Scale for the Assessment of Negative Symptoms(SANS), Positive And Negative Symptom Scale(PANSS), Clinical Assessment Interview for Negative Symptoms(CAINS), Korean Facial Expressions of Emotion(KOFEE) and Eyes task. Correlation analysis, structural equation modeling(SEM), and stepwise regression analysis were used to analyze data. Results:Social cognition was significantly correlated with negative symptoms rather than positive symptoms. Eyes task was negatively correlated with CAINS total score and both two subdomains. Although Eyes task was a significant predictor for both subscales of CAINS, it had more explanatory power for motivation/pleasure subdomain than expression subdomain. The results of SEM, model that KOFEE effects Eyes task and Eyes task effects each negative symptoms, motivation/pleasure, expression indicated most good fit. Conclusion:These findings confirmed the hypothesized relations that social cognition has more strong correlation with negative symptoms rather than positive symptoms. In addition these results provide empirical support for pathway which reduced social cognition ability impacts on developing negative symptoms.

HFLC에 의한 유도전동기 드라이브의 직접 토크제어

문주희(Ju-Hui Mun),고재섭(Jae-Sub Ko),최정식(Jung-Sik Choi),정철호(Cheol-Ho Jung),강성준(Sung-Jun Kang),장미금(Mi-Geum Jang),정동화(Dong-Hwa Chung) 대한전기학회 2010 대한전기학회 학술대회 논문집 Vol.2010 No.4

An induction motor operated with a conventional direct self controller(DSC) shows a sluggish response during startup and under changes of torque command. Fuzzy logic controller(FLC) is used in conjection with DSC to minimize these problems. AFLC chooses the switching states based on a set of fuzzy variables. Flux position, error in flux magnitude and error in torque are used as fuzzy state variables. Fuzzy rules are determinated by observing the vector diagram of flux and currents. This paper proposes hybrid fuzzy controller for direct torque control(DTC) of induction motor drives. This controller is controlled speed using hybrid fuzzy logic controller(HFLC) and estimation of speed using ANN. The performance of the proposed induction motor drive with HFLC controller and ANN is verified by analysis results at various operation conditions.

유도전동기의 최대토크 제어를 위한 AIPI 제어기 개발

강성준(Sung-Jun Kang),고재섭(Jae-Sub Ko),최정식(Jung-Sik Choi),정철호(Cheol-Ho Jung),백정우(Jeong-Woo Baek),장미금(Mi-Geum Jang),정동화(Dong-Hwa Chung) 대한전기학회 2010 대한전기학회 학술대회 논문집 Vol.2010 No.4

The maximum output torque developed by the machine is dependent on the allowable current rating and maximum voltage that the inverter can supply to the machine. Therefore, to use the inverter capacity fully, it is desirable to use the control scheme considering the voltage and current limit condition, which can yield the maximum torque per ampere over the entire speed range. This controller is controlled speed using artificial intelligent PI(AIPI) controller. Also, this paper is proposed control of maximum torque per ampere(MTPA) of induction motor. The performance of the proposed induction motor drive with maximum torque control using AIPI controller is verified by analysis results at dynamic operation conditions.