망막전위도의 전력 산출

원철호,조진호,김상하,임정훈 경북대학교 의학연구소 1999 경북대학교병원의학연구소논문집 Vol.3 No.1

주파수영역에서 망막전위도의 총전력을 계산하고, 시간영역에서 망막전위도의 면적을계산할수 있는 프로그램을 개발함으로써 전기생리학적 진단의 효능을 향상시키는데 목적을 두었다. 총전력은 망막전위도 신호를 Fourier 변환을 이용하여 주파수 영역의 신호로 바꾼 다음 스펙트럼의 제곱을 적분함으로써 구하였다. 우세전력은 우세주파수의 전력으로 이부분의 전압을 제곱후 적분하여 얻은 값이다. 원하는 부분은 수동입력하여 구간주파수의 제곱적분을 할 수 있게 하였다. 이 소프트웨어는 시간 영역에서 진동양소파의 진폭의 합 및 면적도 구할 수 있는 기능을 가졌으며, 사용자에게 편리하도록 그래픽 환경 하에서 마우스와 팝업 메뉴에 의하여 각 기능들이 작동되며, UTAS-E2000 시스템과도 상호 호환성을 갖고 있다(한안지 38:817∼823, 1997). The Calculation of the Electroretinographic Power Chul Ho Won*, Jin Ho Cho, Ph.D.**, Sang Ha Kim, M. D., Jung Hoon Lim, M. D. To promote the electrophysiologic diagnostic efficiency, the program for calculation of the total power in the frequency domain and of the area in the time domain of the electroretinogram was designed. The total power is calculated by integration of the squared power spectrum obtained by Fourier transform (Parseval theorem) in the time domain. The dominant power is the power of the dominant frequency in power spectrum and is calculated by integration of the squared peak area spectrum. The sectional integration of the square power spectrum can be established by manual input. The implemented software also has the functions that calculate the summed amplitude and area of the oscillatory potentials in the time domain. And it performs each functions by selection of pop-up menu with mouse to use conveniently under graphic interface, compatible with UTAS-E2000 system (J Korean Ophthalmol Soc 38:817∼823, 1997).

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

쉘 요소를 이용한 박판 성형 공정 해석의 산업현장 적용에 관한 연구

정동원,고형훈,문원섭 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.2

Finite element analysis of sheet metal forming process is generally carried out by the explicit and implicit time integration method. And membrane, shell and continuum element are applied to finite element analysis. Membrane analysis can not provides sufficient information for the process which involve considerable bending effects. Shell element allows the consideration of bending effects, but involves too much computational time. In order to estimate in sheet metal forming processes used Auto-Form software using static-implicit method and shell element. Result, by applying this to an industrial site the productivity improvement and cost reduction etc. effect able was predicted.

정적-내연적 이론을 이용한 Cowl Top Otr 판넬 해석에 관한 연구

정동원,안현길,고형훈,문원섭 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.1

The static implicit finite element method has been effectively applied to analyze total cowl top otr panel stamping processes, which include the forming stage. Complicated and abnormal large size cowl top otr panel was analyzed by using commercial program called AutoForm. Analysis results examining possibility and validity of the AutoForm software and the factor study are presented. Furthermore, the simulated results for the total cowl top otr panel stamping processes are shown and discussed. Its application is being increased especially in the automotive industry for the cost reduction, weight saving, and improvement of strength.

오토폼 소프트웨어를 사용한 원통형상의 드로잉 공정해석

정동원,고형훈,문원섭 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.1

Drawing process at the household goods until industrial site is used in the various filed. This study are drawing process analysis using Auto-Form software which used a Static-implicit time integration method. Analysis simulation result, it was possible to know that choice of a bead and blank size choice can be optimized through a forming analysis. By making apply this to an industrial site the productivity improvement and cost reduction etc. effect able was predicted.

On the Strengthening Effects Affecting Tensile and Low Cycle Fatigue Properties of Low-Alloyed Seismic/Fire-Resistant Structural Steels

Jung‑Ho Sim,Tae‑Yeong Kim,Jun‑Yeon Kim,Chi‑Won Kim,Jun‑Ho Chung,Joonoh Moon,Chang‑Hoon Lee,Hyun‑Uk Hong 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.2

In the present study, low carbon ferritic and bainitic steels with different contents of Mo, Ti, and Nb were designed for bothseismic and fire-resistant applications. The microstructure of steels containing 0.3 wt% Mo–0.02 wt% Nb (‘A’ hereinafter)was mainly composed of bainite. By contrast, the microstructure of steels with 0.2 wt% Mo–0.13 wt% Ti (‘B’ hereinafter)consisted of ferrite with a high density of nano-sized (Ti,Mo)-rich MX precipitates. The results showed that the bainiticmicrostructure (‘A’ steel) was quite favorable to high-temperature strength and thermal stability. The yield strength of ‘A’ steelat both room and 600 °C temperatures increased consistently with increasing thermal exposure time (600 °C/200–1000 h),since the precipitation of NbC particles occurred while maintaining bainitic ferrite platelets with a high density of dislocationsduring exposure. In the ‘B’ steel, the formation of nano-sized (Ti,Mo)-rich MX particles was effective to impededislocation movement, leading to excellent plasticity (lower yield ratio) at room temperature. However, their contributionto precipitation hardening was not so much at 600 °C, as compared to the bainitic strengthening. During low cycle fatiguetests at room temperature, the main different feature between the two steels is that the ‘A’ steel showed cyclic softeningwhile cyclic hardening was evident in the ‘B’ steel. The bainitic microstructure showed a better fatigue life due to increasedductility manifested by cyclic softening, by which dislocation cell was developed.

발열을 동반한 호중구감소증에서 Cefepime 단독투여와 Ceftazidime 및 Tobramycin 병합투여의 효능비교

정현욱,채제욱,강미라,양정채,문치숙,기현균,장현하,오원섭,김기현,백경란,이남용,송재훈 대한감염학회 2004 감염과 화학요법 Vol.36 No.6

목적 : 국내에서 발열을 동반한 호중구감소증이 있는 악성 종양환자에게 경험적 항생제로 베타락탐계 항생제와 아미노배당체의 병합요법의 사용이 일반적이다. Cefepime은 광범위 항균 작용을 가지고 있어, 그람 음성균 뿐만 아니라 그람 양성균에 대해서도 우수한 효과를 나타낸다. 재료 및 방법: 발열을 동반한 호중구감소증이 있는 악성 종양환자를 대상으로 무작위, 공개, 비교 연구를 시행하였다. 대상 환자를 무작위로 cefepime 단독요법군과 ceftazidime 및 tobramycin 병합요법군으로 나누어 투여하고 각각의 임상적 효능과 안전성을 비교하였다. 구강및 인후 점막염이 있는 환자에서 분리된 녹색 연쇄알 구균에 대한 항생제 내성 정도를 조사하였다. 결과 : 대상환자 89명 중 CA 투여군이 48예(53.9%), CT 투여군이 41예(46.1%)이었다. 발열의 유형별로 MDI는 18예(20.2%), CDI는 9예(10.1%), UF는 62예(69.7%)로 두 군 간에 차이가 없었다. CA 투여군과 CT 투여군의 임상적 호전률은 시험약 투여 후 2-4일째 각각 91.7%, 85.4% (P=0.31), 치료 종료 시 각각 91.7%, 100% (P=0.15)로 두 군간에 유의한 차이가 없었다. 치료 종료 시 CA 투여군과 CT 투여군의 세균학적 소실률은 모두 100%로 두 군간의 유의한 차이가 없었다(P=0.78). 점막염이 있는 환자로부터 녹색 연쇄알 구균이 분리된 경우는 25예(28.1%)이었으며, 분리된 녹색 연쇄알 구균은 penicillin, ceftriaxone, cefepime, vancomycin에 모두 감수성을 보였다. 약제 관련 이상 반응의 발생 빈도도 두 군간에 유의한 차이가 없었다. 결론 : 발열을 동반한 호중구감소증이 있는 악성 종양환자의 경험적 항생제로서 cefepime 단독요법은 ceftazidime 및 아미노배당체의 병합요법만큼 효과적이고 안전하였다. Background : Broad-spectrum antibiotic therapy has been recommended as an empirical regimen in cancer patients with febrile neutropenia. Cefepime is a fourth generation cephalosporin with good activity against both gram-positive cocci and gram-negative bacilli. Materials and Methods : To compare the efficacy and safety of cefepime alone with ceftazidime plus tobramycin as empirical regimen for adult cancer patients with febrile neutropenia, a randomized, open label, comparative trial was performed. If the patient showed clinical improvent 72 hours, antibiotic could be changed to oral ciprofloxacin. Clinical and microbiological responses were determined at 72 hours and at the end of therapy. To investigate the antimicrobial resistance of viridans streptococci, swab cultures were obtained from throat in all enrolled patients and antimicrobial susceptibility tests were performed by using microdilution method according to the NCCLS. Results : A total of 89 patients were enrolled. Forty-eight patients received cefepime alone (CA), and 41 patients received ceftazidime plus tobramycin (CT). Demographic and baseline clinical characteristics were similar in both groups (P>0.05). The initial clinical success rate at day 2-4 in group CA (91.7%) was similar with that in CT group (85.4%) (P=0.31). At the end of therapy, the final clinical success rate in CA group (91.7%) was similar to that in CT group (100%) (P=0.15). In 18 patients, with microbiologically defined infections, the eradication rate was 100% in both groups. Adverse events including liver dysfunction (21.3%) and renal dysfunction (2.2%), were similar in both groups (P=0.87). Viridans streptococci were isolated from the throat cultures in 25 cases, and all of these strains were susceptible to penicillin (MIC_(90) 0.12 ㎍/mL), cefepime (1 ㎍/mL), and vancomycin (0.12 ㎍/mL). Conclusion : Efficacy and safety of cefepime monotherapy was comparable to the combination of ceftazidime and tobramycin. It could be used as an alternative empirical regimen for treating cancer patients with febrile neutropenia.

PNL S/ABS HUS’G L/R 제품개발을 위한 성형해석

정동원,고형훈,문원섭 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.1

The characteristic of sheet metal process is the few loss of material during process, the short processing time and the excellent price and strength. FEA applications with the sheet metal forming process is purpose that increasing due to the potential of time and cost saving. This study are industrial field problem solve using AutoForm which used a Static implicit way. According to this study, the results of simulation will give industrial site good information to access the Design sheet metal forming.

구분모우드합성법을 이용한 판의 모우드해석

정재훈,박영필,유원희 연세대학교 산업기술연구소 1991 논문집 Vol.23 No.2

Component mode synthesis which is one of substructure synthesis methods is studied for the determination of vibration characteristics of plate problem. Comparisons are made in terms of accuracy and computational efficiency. As a result, computation time of component mode synthesis is much shorter than that of whole structure analysis. In lower modes natural frequencies obtained from component mode synthesis are almost equal to those obtained from whole structure analysis, but in higher the differences of results obtained from two methods are increased.

실내기상인자의 다중회귀분석에 의한 라돈농도 예측

이원근,김정훈 경희대학교 산학협력기술연구원 2002 산학협력기술연구논문집 Vol.8 No.-

The purpose of this study was examine the relationship of meterological factors, including temperature, pressure and pressure difference, to indoor radon concentration in a bid to set up an equation to predict indoor radon concentration. When their relationship was analyzed, it's found that temperature exerted the greatest influence on the change in radon concentration. There appeared positive correlation between the two. But the radon concentration was negatively correlated to indoor pressure or pressure difference. An equation for radon concentration prediction was established in consideration of these results. It' attempted to substitute temperature, pressure and pressure difference for the equation to find out how much radon existed, and then no significant discrepancy was detected between the predicted concentration and actually gauged one. This finding suggested that in case indoor temperature rises, radon concentration could be reduced in the same space by lowering it through ventilation. In addition, information on temperature, pressure and pressure difference would be enough to predict average radon concentration left in a specific space, without actually measuring it.