고속전철 추진 시스템의 미끄럼 방지 제어기법에 관한 연구

황돈하,김동희,노채균,심광열,조규판,정원영 영남대학교 공업기술연구소 1999 工業技術硏究所論文集 Vol.27 No.2

Induction motor drive with PWM inverter control has been developed for Korean High Speed Railways. To improve traction performance, the anti-slip control(ASC) to recover adhesion must be considered. This paper describes a novel hybrid anti-slip control method for the induction motor drive. By introducing the vector control for drive system, quick response of the motor torque can be achieved when wheels are going to slip. A hybrid control scheme by mixing two conventional control methods (slip velocity feedback control and slip detection pattern control) for wheel slip and re-adhesion is proposed. This control method is simulated by motor drive, train load, and friction-creep models. The train running simulation results based on induction motor vector control with PWM inverter show that good re-adhesion characteristics are obtained.

인버터 구동용 유도전동기 고정자 권선의 절연특성 연구

황돈하,김동희,이광식,정원영,김영훈,오승훈 영남대학교 공업기술연구소 1999 工業技術硏究所論文集 Vol.27 No.2

Inverters with high speed switching and advanced PWM techniques are widely used for variable speed applications. But some adverse effects on the stator winding insulation are reported due to excessive voltage stress, which results in the premature insulation breakdown. This is aggravated by the high switching speed of modem switching devices such as IGBT (Insulated Gate Bi-polar Transistor) with which the rate of rise in voltage (dv/dt) increases considerably. In this paper, the test results for evaluation on the stator winding insulation of 310V induction motors are presented. Also, the insulation characteristics are presented in order to analyze the insulation strength under high voltage due to high switching speed of IGBT PWM inverter. 26 induction motors of 6 types with different wires and insulation techniques are built and thoroughly tested. The maximum partial discharge (PD) magnitude (Qm) and the discharge inception voltage (DIV) are obtained by PD test. Under AC current test, the rate of change in AC current (ΔI) and the change in dissipation factor (Δtanδ) are measured. From the above test data, the effects due to different wires and insulation techniques on the insulation characteristics of low-voltage induction motors are compared and analyzed. The insulation technique to enhance the insulation strength is suggested from the test results.

실관막에 의한 Cd(Ⅱ) 및 Cu(Ⅱ)의 액-액 추출에 관한 연구

황덕기,박동원 동아대학교 환경문제연구소 1993 硏究報告 Vol.16 No.2

The extraction of Cd(Ⅱ) and Cu(Ⅱ) in mixed aqueous solution was studied with TOA(tri-n-octylamine) dissolved in aromatic organic solvents using HFSLM(hollow fiver supported liquid membrane). HFSLM module with constant volume was used to measure mass transfer coefficients of the extraction with mixed aqueous solution under acidic condition at 25℃, and overall mass transfer coefficients were increased with increasing initial concentration of HCI in mixed aqueous solution, with increasing velocity of inner fibers.

한국인 정신분열병과 HLA-DRB1 대립유전자의 관련성

황나영,김종원,오흥범,조지희,오선영,홍진표,박종익,이동은 大韓神經精神醫學會 2000 신경정신의학 Vol.39 No.5

연구목적: 유전이 정신분열병의 중요한 원인이라는 것은 널리 인정되어 왔다. 본 연구는 한국인 정신분열병과HLA-DRB1 유전자좌와의 관련성을 알아보고 외국인 대상의 보고들과 비교함으로써 한국인 정신분열병의 유전적 특성을 밝히고자 시행하였다. 방법: 정신분열병 환자 70명을 대상으로 HLA-DRB1 대립유전자를 고해상도 수준까지 분석하였다. 저해상도 수준의 HLA-DR결과는 정상 한국인 2,000명의 연구 보고와 비교하였으며 고해상도 수준의 HLA-DRB1 결과는 정상 한국인 229명의 연구 보고와 비교하였다. 결과: 저해상도 수준에서는 HLA-DR11이 정신분열병 환자군에서 9.0%, 정산인에서는 3.8%의 빈도를 보여 환자군에서 통계적으로 유의하게 높은 빈도를 보였으며(p=0.005), 고해상도 수준에서는 HLA-DRB1*1101이 환자군에서 9.0%로 정상인의 1.8%보다 유의하게 높은 빈도를 보였다(p<0.001). 결론: 본 연구에서는 한국인 정신분열병과 HLA-DR11(HLA-DRB1*1101)이 양적 상관관계를 보여 백인에서 DR4와 부정적 상관관계를 보인 결과나 일본인에서 DR1(DRB1*0101)과 양적 상관관계를 보인 결과와 상이하였다. 이러한 한국인 정신분열병 환자의 유전적 특성은 가족연구 혹은 더 많은 수의 환자를 대상으로 한 관련연구를 통하여 재확인되어야 할 것이다. 중심단어:정신분열병·HLA-DRB1·관련연구. Objective: A genetic predisposition is widely accepted in schizophrenia. This study was intended to fine any association of HLA-DRB1 alleles with korean schizophrenics and thereby compare the results of other ethni groups. Method: The subjects were 70 unrelated Korean patients. Low and high resolution typing of HLA-DRB1 alleles were performed. The comparison groups were 2,000 unrelated healthy Koreans for low resolution HLA-DR and 229 unrelated healthy Koreans for HLA-DRB1 alleles. Results: Gene frequencies of HLA-DR11(patients 9.0%, healthy control 3.8%, p=0.005) and HLA-DRB1*1101(patients 9.0%, healthy control 1.8%, p<0.001) were significantly higher in Korean schizophrenics. Conclusion: The frequency of HLA-DR11(HLA-DRB1*1101) is significantly higher in Korean schizophrenics than in healthy Koreans. HLA-DR4 and HLA-DR1, which were known to be associated with Caucasian and Japanese schizophrenics, respectively, did not show statistical association with Korean schizophrenics. This association need to be reassured though further studies with families or association study with larger numbers of subjects. KEY WORDS:Schizophrenia·HLA-DRB1·Association study.

그라프트 중합에 의한 클로로프렌 고무의 물성에 관한 연구

황승순,이상호,손진언,박동원 동아대학교 생산기술연구소 2002 生産技術硏究所硏究論文集 Vol.7 No.1

Graft-copolymerization were performed with poly(chloroprene) and methyl methacrylate (MMA) in order to determined the effects of initiator concentration, reaction time, and nitrogen purging on the kinetics of the copolymerization and physical properties of the copolymer. At high concentrations of initiator poly(chloroprene-graft-methyl methacrylate) is more viscous in case that nitrogen is purged during the copolymerization, compare to the copolymerization under air environment. The conversion of MMA increases with the concentration of initiator while the elongation of the copolymer maintains relatively steady. After the copolymerization elapses around 3 hours with nitrogen purging, the viscosity of the copolymer increases rapidly. However, the viscosity is almost steady regardless of time under air environment. Whereas the conversion of MMA increases with reaction time, the efficiency of grafting decreases. The graft copolymer prepared in air has relativity constant tensile strengths of 200 Kgf/cm2. The copolymer prepared with nitrogen purging has tensile strengths grater than 250 Kgf/cm2 and shows a maximum value, 275 Kgf/cm2, at the reaction time of 2.5 hours. Drying the solvents used to make chloroprene adhesive is faster in order of methyl alcohol, methyl cyclopentane, o-xylene, and cyclohexane.

상아세관의 주행방향에 따른 상아질 접착제의 침투양상에 대한 공초점레이저주사현미경적 연구

김동준,황윤찬,김선호,오원만,황인남 전남대학교 치의학연구소 2003 구강과학 Vol.15 No.1

The purpose of this study was to evaluate the penetration pattern of dentin adhesives according to the orientation of dentinal tubules with confocal laser scanning microscopy Specimens having perpendicular, parallel and oblique surface to dentinal tubules were fabricated. The primer of dentin adhesives (ALL BOND�2, CLEARFIL^(TM) SE BOND and PQ1) was mixed with fluorescent material, rhodamine B isothiocyanate (Aldrich Chem. CO., Milw., USA). It was applied to the specimens according to the instructions of manufactures. The specimens were covered with composite resin (Estelite, shade A2) and then cut to a thickness of 500 ㎛ with low speed saw (Isomet^(TM), Buehler, USA). The adhesive pattern of dentin adhesives were observed by fluorescence imaging using confocal laser scanning microscopy. The results were as follows. 1. For the groups with tubules perpendicular to bonded surface, funnel shape of resin tag was observed in all specimen. However, resin tags were more prominent in phosphoric acid etching system (ALL BOND� 2 and PQ1) than self etching system (CLEARFIL^(TM) SE BOND). 2. For the groups with tubules parallel to bonded surface, rhodamine-labeled primer penetrated into peritubular dentin parallel to the orientation of dentinal tubules. But rhodamine-labeled primer of PQ1 diffused more radially into surrounding intertubular dentin than other dentin adhesive systems. 3. For the groups with tubules oblique to bonded surface, resin tags appeared irregular and discontinuous. But they penetrated deeper into dentinal tubules than other groups.

鐵道騷音의 豫測技法에 關한 硏究

윤해동,황원택,김재수 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

With rapidly industrial development, a railway has become of a main traffic means. But, the railway noise has caused much annoyance for the residents living nearby railway tracks. The result has been indiscreet installation of soundproof walls. But, even after soundproof walls were installed, the residents in the area would complain about the railway noise. In this study. The characteristics of Propagation and Attenuation of railway noise were compared among regions where the Honam Line travels. For this focus, the characteristics of sound field distribution of the soundproof walls in the area were investigated, and the results were supposed to serve as a basic data for effective and rational noise prevention measures.

공정제어에의 應用을 위한 마이크로 콤퓨터 시스템의 개발

李秀東,禹治水,李泰鎬,朴源深,黃德浩 울산대학교 1978 연구논문집 Vol.9 No.2

마이크로 프로세서를 이용한 디지탈 공정제어 수단이 고찰되었다. 관심의 초점은 분산-종합제어에 적합한 단말제어 프로세서에 두었다. 시험 제작된 프로세서는 8개의 제어 루우프를 운전하는 독립된 제어장치이며 동시에 종합제어를 위하여 상위 전산기와 데이타 교환이 가능하도록 설계 되었다. 주기적 샘플링에 의한 비례-적분-미분(PID)제어방식을 기본으로 하고 있으며 파라메터 값에 의하여 PI,PD등으로 축소될 수 있도록 하였다. 시험 장치에서는 주기를 2초로 하였는데 A/D변환기의 적절한 선정에 의하여 0.2초정도 까지는 쉽게 단축할 수 있다. 조작자용의 프로세서에 대한 고찰은 최소한의 기능을 가진 것에 한정하였으며 이는 실제 적용 현장과 관련하여 기능이 확장되어야 할 것이다. 사용된 마이크로 프로세서는 범용의 것으로 단말용에는 M6800계통을, 조작자용에는 SC/MP계통을 사용하였다. A microprocessor based digital process controller has been studied. The objective was to develope a stand-alone terminal processor for distributed on-line control systems. The prototype terminal proposed in this paper has the capability of handling eight independent control loops under the supervisory control of main computer and/or operator console. The control algorithm follows analog PID action based on periodically sampled data. The control action can also be reduced to PI,PD and so forth through parameter assignment. Availability of A/D converters to the authors limited sampling period to 2 seconds, but it could easily be reduced to 0.2 sec. employing appropriate A/D devices. The number of operational functions of console processor is kept minimum in this study, the expansion of which should be done for particular application. Hardware implementation was done with general purpose microprocessors; M6800 system for terminal and SC/MP system for console.

주의력결핍/과잉행동장애와 양극성장애 공존 환아군과 주의력결핍/과잉행동장애 환아군의 비교연구

정동선,하규섭,정희연,구훈정,황준원,김붕년,신민섭,조수철,홍강의 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.6

Objective : Attention deficit hyperactivity disorder (ADHD) is frequently comorbid with a variety of psychiatric disorders. Among them, bipolar disorder (BPD) has especially attracted growing interest. This is partly due to the fact that early onset BPD has been frequently misdiagnosed as ADHD because of symptomatic overlap. The aim of the present study is to find the differences in demographic data and clinical features of ADHD+BPD and ADHD in children and adolescents. Method : Children and adolescents patients participating in the present study have been enrolled at the child psychiatric clinic since 2004. 14 patients meeting the DSM-IV chteria for ADHD+BPD and 19 patients meeting the criteria for ADHD and 15 healthy comparison subjects were recruited. All groups were evaluated through the Schedule for Affective disorders and Schizophrenia for School-Age Children-Present and Life Time version-Korean version (K-SADS-PL-K). Demographic data and clinical charactehstics of the subjects were also collected. Parents were asked to complete the Child Behavior Check List(CBCL) and the Toddler Temperamental Scale (TTS) clinical ratings were obtained using the Young Mania Rating Scale(YMRS), the Children's Depression Iventory (CDI) and the Dupaul ADHD scale. Clinical variables between ADHD+BPD and ADHD were analyzed using the Mann-Whitney U test. YMRS, CDI, Dupaul ADHD scale (inattention and hyperactivity), CBCL, and TTS among the three groups were analyzed using the Kruskal-Wallis test with post-hoc Mann-Whitney U test. Results : 1) ADHD+BPD group had an earlier onset age of ADHD than ADHD group 2) ADHD+BPD group had more co-morbid psychiathc disorders than ADHD group. 3) Compared to ADHD group, ADHD+BPD had more psychiathc family history, especially mood disorders. 4) ADHD+BPD group had prodromal symptoms such as irritability, anger dyscontrol and academic dysfunction, compared to ADHD group who rarely showed prodromal symptoms. 5) ADHD+BPD group had higher ADHD scores than the ADHD group in the Dupaul ADHD inattentive scale. 6) In global functions of CBCL, ADHD+BPD group showed more impaired functions at home and school than ADHD group. 7) In Attention diagnostic system (ADS), ADHD+BPD group had more omission and commission errors than ADHD group, especially in the visual system. 8) In the subtests of the IQ profile, ADHD+BPD group had lower arithmetic and block design scores than ADHD group. Conclusion : Clinicians have to rule out underlying bipolarity in children and adolescents with ADHD who show earlier age of onset and severe clinical features. Bipolarity should be explored intensively in ADHD children and adolescents who have early onset of symptoms and severe functional impairment.

폴리에스터 흡음재가 조합된 다공판 시스템의 흡음성능에 관한 연구

서성원,황윤,이동훈 서울産業大學校 2002 논문집 Vol.53 No.1

The sound absorption coefficients for perforated plate systems containing several compartments with airspaces and polyester absorbing materials are estimated using the transfer matrix method developed in the previous paper. The absorption coefficients from transfer matrix method agree well with the values measured by the two-microphone impedance tube method for various combinations of perforated plates, airspaces or absorbing materials. Based on these results. a guidance for the design of perforated plate systems combined with airspaces and absorbing materials is discussed in detail.