대형물의 RP 작업을 위한 절단 알고리즘의 개발

채희창,강희용,유상훈,이승현,문홍렬 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.2

Nowadays, as the development period of new products becomes shorter and consumer's requirement is more various, the importance of Rapid Prototyping Technology has been rapidly increased. Rapid Prototyping makes prototypes or functional parts directly using the 3D CAD data. But RP machines can make protypes in limit size. For making large size prototype, we slice solid, which is made of STL file, and then glue sliced solid. And if contact area of part is small, union solid will be easily destroyed for going down of adhesion. So we need to expand contact area, I suggest making a section into stair shape. This paper is concerned with slicing solid on STL file and improving on adhesion.

LPE법에 의한 InGaAsP/InP 양자우물 구조 성장

김의훈,오차환,문승준,김채옥 漢陽大學校 自然科學硏究所 1997 自然科學論文集 Vol.16 No.-

InGaAsP /InP 양자우물 구조를 액상 에피탁시법으로 성장하여, 그 구조적 특성을 secondary ion mass spectroscopy(SIMS), scanning emission microscopy(SEM), transmission electron microscopy(TEM)을 이용하여 조사하였다. SIMS 결과로 부터 well과 barrier의 interface에서 P와 As의 성분이 매우 급준한 변화를 보이고 있는 것으로 보아 LPE로 성장된 시료의 계면구조도 비교적 잘 control이 되었다고 판단된다. SEM과 TEM단면 사진으로 부터 well과 barrier의 계면 상태가 양호하고 well size가 270Å이고 barrier size가 1200Å임을 알 수 있었다. InGaAsP /InP quantum well structures have been grown by liquid phase epitaxy(LPE) and its structural properties have been studied by SIMS, SEM and TEM. In SIMS measurement, the P - and As-components were varied abruptly between wells and barriers, which means that interfacial structures of sample grown by LPE were controlled very well. From the analysis of cross sectional images by SEM and TEM, we know that the interfaces between wells and barriers are very abrupt and that the thickness of well layers and barrier layers are 270Å and 1200Å, respectively .

InGaAsP/InP 양자우물 구조의 물성연구

김채옥,오차환,문승준,김의훈 漢陽大學校 自然科學硏究所 1997 自然科學論文集 Vol.16 No.-

Liquid phase epitaxy(LPE)법에 의해 InGaAsP quantum well(QW)구조를 성장하여 특성을 photoluminescence(PL)와 double crystal rocking curve(DCRC)를 이용하여 조사하였다. PL 측정결과, 상온 PL의 경우 well특성의 피크 에너지는 0.97eV이 FWHM은 80.41meV이며, 저온PL결과 well특성의 피크 에너지는 1.025eV이고 FWHM은 33meV이었다. 여기광의 세기를 증가시킴에 따라 PL 세기가 비교적 선형적으로 급준한 증가를 보이고 있어 well발광 특성임을 관찰할 수 있었다. DCRC결과, 격자부정합도가 0.32이고 한 쌍의 주기는 600Å이며 전형적인 Quantum Well특성의 위성피크를 관찰할 수 있다. In this work, We have grown the InGaAsP/InP quantum well by liquid phase epitaxy(LPE) and its some physical properties have been studied by photoluminescence(PL) and double crystal x-ray rocking curve(DCRC). In low temperature PL, the characteristic emission peak of well is observed at 1.025eV with a full-with-half-maximum of 33meV. As we increase the excitation intensities the emission intensities are drastically increased. From the DCRC analysis, we know that lattice mismatch between epitaxial layer and substrate is very low with a value of 0.32.

제대혈액에서 골조직 특이세포로의 분화

홍승진,이은아,채규태,한훈 Official Journal of the Korean society for immunol 2002 Immune Network Vol.2 No.3

통풍성 관절염의 임상적 고찰

윤채중,정승문,김영학,김동규,허광식,김태원,배학연,정종훈,이승일,김평남 朝鮮大學校 附設 醫學硏究所 1997 The Medical Journal of Chosun University Vol.22 No.2

통풍은 Purine 대사의 이상으로 발생하는 질환으로, 고뇨산혈증인 사람의 전부가 통풍으로 발현되지 않고 증상의 출현 양상이 다양하여 진단과 치료에 주의가 필요하며, 조기에 적절한 조치를 한다면 충분히 조절이 가능한 질환이다. 본대학 내과학교실에서는 통풍으로 치료한 32명의 환자에서 임상양상, 병력과 검사소견을 분석하여 다음과 같음 결과를 얻었다. 1. 32명 모두 남자이며, 최초 발병 시기는 24세에서 72세로 평균 43.8±11.9세이었으며, 30대에서 40대까지가 19명(59.4%)으로 대부분을 차지하였다. 내원 당시 나이는 27세에서 75세까지로 평균 52.3±10.4세였으며, 내원시 까지 평균 유병기간은 8.5±6.8년으로 나타났다. 2. 동반 질환으로는 고지혈증 12례, 신장질환 10례, 고혈압 12례, 비만 8례, 당뇨 2례 등이었다. 3. 이환된 관절은 단관절 침범이 19례(59.4%), 다관절 침범이 13례 이었으며, 최초 이한된 관절은 족무지 중족골지골 관절로 19례(59.4%)로 가장 많았고, 통풍 결절은 20례(62.5%)에서 관찰되었으며, 유병기간이 10년 이상된 12례중 11례 (91.7%)에서 결절이 관찰되었다. 4. 평균 혈중 요산치는 9.17±1.75 ㎎/dl이었으며, 8.0 ㎎/dl에서 9.9 ㎎/dl 사이가 19명으로 전체의 59.4%를 차지하였다. Objective: The gout is a heterogeneous group of diseases resulting from tissue deposition of monosodium urate or uric acid crystals from extracellular fluids supersaturated with respect to this end product of human purine metabolism. The clinical manifestations are such as hyperuricemia, gouty arthritis, gouty nephropathy, uric acid nephrolithiasis. We analyze of clinical manifestations and associated factors in gout. Method: We have reviewed the medical records, radiologic findings and clinical results of thirty-two patients admitted at our department from April 1996 to July 1997. Result: 1) All patients were male. The mean age at initial attack was 43.8 years old, ranging from 24 to 72 years old. 2) The mean level of serum uric acid was 9.17mg/dl on admission. 3) The first metatarsopharyngeal joint was involved in 19 cases (59.4%). Tophus was observed in 20 cases (62.5%). 4) Hyperuricemia was associated with hypertension, obesity, nephrolithiasis and hyperlipidemia.

BGA패키지에서의 무연솔더 접합부 전단 시험법의 최적화

김종웅,문정훈,서창제,정승부 대한금속ᆞ재료학회 2006 대한금속·재료학회지 Vol.44 No.3

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.

Lung Segmentation Using Prediction-Based Segmentation Improvement for Chest Tomosynthesis

Seung-Hoon Chae,Jeongwon Lee,Chulho Won,Sung Bum Pan 보안공학연구지원센터 2014 International Journal of Bio-Science and Bio-Techn Vol.6 No.3

Parallel Processing of the Fuzzy Fingerprint Vault based on Geometric Hashing

( Seung-hoon Chae ),( Sung Jin Lim ),( Sang-hyun Bae ),( Yongwha Chung ),( Sung Bum Pan ) 한국인터넷정보학회 2010 KSII Transactions on Internet and Information Syst Vol.4 No.6

User authentication using fingerprint information provides convenience as well as strong security. However, serious problems may occur if fingerprint information stored for user authentication is used illegally by a different person since it cannot be changed freely as a password due to a limited number of fingers. Recently, research in fuzzy fingerprint vault system has been carried out actively to safely protect fingerprint information in a fingerprint authentication system. In addition, research to solve the fingerprint alignment problem by applying a geometric hashing technique has also been carried out. In this paper, we propose the hardware architecture for a geometric hashing based fuzzy fingerprint vault system that consists of the software module and hardware module. The hardware module performs the matching for the transformed minutiae in the enrollment hash table and verification hash table. On the other hand, the software module is responsible for hardware feature extraction. We also propose the hardware architecture which parallel processing technique is applied for high speed processing. Based on the experimental results, we confirmed that execution time for the proposed hardware architecture was 0.24 second when number of real minutiae was 36 and number of chaff minutiae was 200, whereas that of the software solution was 1.13 second. For the same condition, execution time of the hardware architecture which parallel processing technique was applied was 0.01 second. Note that the proposed hardware architecture can achieve a speed-up of close to 100 times compared to a software based solution.

Relationship Between Coronavirus Disease 2019 Vaccination Rates and Rare But Potentially Fatal Adverse Events: A Regression Discontinuity Analysis of Western Countries

Chae Seung Hoon,Park Hyung Jun,Radnaabaatar Munkhzul,Park Hojun,정재훈 대한의학회 2023 Journal of Korean medical science Vol.38 No.11

Background: Owing to limited experience with the new vaccine platforms, discussion of vaccine safety is inevitable. However, media coverage of adverse events of special interest could influence the vaccination rate; thus, evaluating the outcomes of adverse events of special interest influencing vaccine administration is crucial. Methods: We conducted regression discontinuity in time analysis to calculate the local average treatment effect (LATE) using datasets from Our World in Data and Johns Hopkins University Center for Systems Science and Engineering. For the United States, the United Kingdom, and Europe, the cutoff points were April 23rd and June 23rd, April 7th, and the 14th week of 2021, respectively. Results: The LATE of the Advisory Committee on Immunization Practices (ACIP) meeting held on April 23rd was −0.249 for all vaccines, −0.133 (−0.189 to −0.076) for Pfizer, −0.064 (−0.115 to −0.012) for Moderna, and −0.038 (−0.047 to −0.030) for Johnson & Johnson. Discontinuities were observed for all three types of vaccines in the United States. The June 23rd meeting of the ACIP (mRNA vaccines and myocarditis) did not convene any discontinuities. Furthermore, there was no significant drop in the weekly average vaccination rates in Europe following the European Medicines Agency (EMA) statement on April 7th. Conversely, there was a significant drop in the first-dose vaccination rates in the United Kingdom related to the EMA report. The first-dose vaccination rate for all vaccines changed by −0.104 (−0.176 to −0.032). Conclusion: Although monitoring and reporting of adverse events of special interest are important, a careful approach towards public announcements is warranted.