헬름홀츠 코일을 이용한 강자성체의 와전류검사

성제중,서동만,신용훈,엄태건,서동섭 한국비파괴검사학회 2003 학술대회 논문집 Vol.- No.1

Ferromagnetic material like the steel tubes can easily distort eddy current testing signal due to increased magnetic permeability for defects. Because magnetic field of the test probe is affected in an inconsistent way when the material under the testing has permeability. This permeability effect can be reduced by magnetic saturation. In this paper eddy current testing system was developed to detect flaws on the steel tubes. Magnetic saturation probe with helmholtz coil was designed for saturation and inspection of the steel tubes. When using the designed test probe, the relationship between flaw signals and noises was obviously discriminated. Additionally, a high pass filter was included in the eddy current board to minimize noises due to DC magnetic field.

급성 림프구성 백혈병 환자에서 발생한 침습성 국균 심내막염 2예

신성철,백경란,정재홍,송봉근,김동희,전경만,채제욱,손준성,정숙인,오원섭,송재훈 대한감염학회 2003 감염과 화학요법 Vol.35 No.5

국균은 호흡기를 통해 유입되며 심한 면역기능저하 환자에서 기회감염을 일으키는 진균이며 주로 혈관을 따라 폐를 침범하고 심장과 골침범은 매우 드문 것으로 알려져 있다. 저자들은 급성 림프구성 백혈병 환자에서 발생한 침습성 국균 심내막염을 2예을 경험하였다. 19세 남자환자로 동종 조혈모세포이식 후 발생한 고열과 요통의 원인으로 감염성 심내막염 진단하에 수술결과 국균에 의한 감염으로 확증되어 수술적 절제술과 liposomal amphotericin B로 치료하였으나 국균 심내막염의 재발과 국균 척추염의 악화, 뇌 출혈로 사망하였다. 23세 남자환자로 관해요법 후 발생한 고열과 요통의 원인으로 국균 심내막염과 국균 척추염 진단하에 수술적 절제술과 amphotericin B로 치료하여 1년 2개월 동안 국균 심내막염의 재발은 없었으나 지속적인 백혈병의 재발과 국균 척추염의 악화, 침습성 폐 국균증으로 사망하였다. Although Aspergillus endocarditis has rarely been reported, it can cause fatal complications in hematologic malignancy patients and allogeneic stem cell transplant recipients. We experienced two cases of aspergillus endocarditis developed in acute lymphoblastic leukemia patients. Case; A 19-year-old patient developed Aspergillus endocarditis after allogenic hemopoietic stem cell transplantation. He was treated with surgical intervention and liposomal amphotericin B. He died of recurred Aspergillus endocarditis and cerebral hemorrhage probably related with aspergillosis of central nervous system. Case 2; A 23-year-old patient developed invasive Aspergillus endocarditis after induction chemotherapy. Aspergillus endocarditis was successfully treated by surgical intervention and amphotericin B. He died of refractory neutropenic fever and sepsis after the third relapse of leukemia and repetitive chemotherapy. He probably had invasive pulmonary aspergillosis without evidence of endocarditis recurrence. Because the mortality of Aspergillus endocarditis is very high, early diagnosis and surgical intervention are very important for better outcome.

운동전략이 기립자세의 기능적 전방 팔뻗기에 미치는 영향

박제상,권오윤,최흥식,김택훈 한국전문물리치료학회 2000 한국전문물리치료학회지 Vol.7 No.1

The purpose of this study is to determine whether movement strategies affect functional forward reach distance in a standing position. Forty-seven healthy subjects were selected for this study: 23 men and 24 women, with an average age of 22.3. Functional forward reach distances were measured as hip strategy and squat strategy(included knee and ankle movement strategy) in a standing position, respectively. The mean values of functional forward reach distance in hip strategy, squat strategy were 33.57㎝, 29.48㎝, respectively. There was significantly difference in functional forward reach distance between hip strategy and squat strategy(p<.001). There was no difference of functional forward reach distance between male and female in hip strategy, but there was significant difference in other strategy(p<.05). These results suggest that movement strategies should be considered during functional forward reach test in standing. Further study is required to determine whether movement strategies affect functional reach distance in elderly and disabled groups.

레니텍^(�) 정(말레인산 에날라프릴, 10mg)에 대한 에나레이스 정의 생물학적 동등성

조성희,하용화,홍성제,서성훈,류재환,김동현,이경태 한국약제학회 2003 Journal of Pharmaceutical Investigation Vol.33 No.3

The purpose of present study was to evaluate the bioequivalence of two enalapril maleate tablets, Renitec^(™) (MSD Korea Ltd.) and Enalace ^(™) (Welfide Korea Ltd.), according to the guidelines of Korea Food Drug Administration (KFDA). Twenty-four normal male volunteers, 22.33±2.55 year in age and 66.54±8.30 ㎏ in body weight, were divided into two groups and a randomized 2×2 cross-over study was employed. After two tablets containint 10 ㎎ of enal-april maleate per tablet wre orally administered, blood was taken at predetermined time intervals and concentrations of enalapril in plasma were determined using LC-MS-MS. Pharmacokinetic parameters such as AUC_(t), C_(max) and T_(max) were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed AUC_(t) and C_(max) untransformed T_(max). There were no sequence effects between two formulations in these parameters. The 90% confidence intervals for the log transfored data were acceptance range of log0.8 to log1.25(e.g., log1.02∼log1.14 and log1.03∼log1.19 for AUC_(t) and C_(max), respectively). The major parameters, AUC_(t) and C_(max), met the criteria of KDFA for bioequivalence indicating that Enalace^(™) tablet is bioequivalent to Renitec^(™) tablet.

IEEE 802.11a 기저대역 프로세서의 설계 및 구현

김상인,최원철,이제훈,조경록 충북대학교 컴퓨터정보통신 연구소 2006 컴퓨터정보통신연구 Vol.14 No.2

본 논문에서는 IEEE 802.11a 표준안에 적합한 기저대역 프로세서를 설계하였다. 프로세서의 크기 감소 및 성능 향상을 위해 새로운 알고리즘이 적용되었다. 구현된 IEEE 802.11a baseband processor는 기존의 OFDM 방식 모뎀의 성능향상을 위해 고속의 IFFT/FFT를 이용하고, 다중경로 채널과 페이딩에 강한 새로운 채널 보상기법과 등화기, tan^(-l) 기법을 이용한 동기회로 그리고 에러 예측 회로를 사용한 비터비 디코더등 개선된 알고리즘을 이용하여 성능향상을 도모하였다 설계된 기저대역 프로세서의 구현 및 검증을 위해 SoC플랫폼을 이용하였다. 플랫폼 기반의 IEEE 802.11a WLAN을 설계하기 위한 환경은 기저대역 프로세서 칩을 테스트하기 위한 테스트 보드와 MAC을 이행할 SoC 플랫폼으로 구성되어 있다. 설계된 IEEE 802.11a baseband processor는 AWGN, 다중 경로 페이딩 채널에서 데이터 전송을 확인하였다.

한국인의 우울증 진단기준의 특성

장성만,손지훈,이준영,최지환,조성진,전홍진,함봉진,이동현,조맹제 大韓神經精神醫學會 2007 신경정신의학 Vol.46 No.5

목적 국내의 여러 역학 조사에 따르면 한국인은 서구에 비하여 우울증의 유병률이 낮은 것으로 보고되고 있다. 낮은 유병률에 대하여 서구에서 정의하는 우울증의 진단 기준이 한국인의 문화에 맞지 않다는 진단 기준의 오류를 제시하거나, 실제로 유병률이 낮다는 설명을 시도하기도 하였다. 본 연구는 DSM-IV에서 제시하는 우울증의 진단 기준에 대하여 한국인의 반응 특성을 알아보고자 한다. 방법 2001년 KECA 연구에 응답한 만 18세 이상 65세 미만의 6,275명을 대상으로 하였다. 한국어판 CIDI (K-CIDI)를 통해 정신장애의 이환을 진단하였으며, K-CIDI 내의 우울장애 진단 기준만을 추출하여 분석하였다. 분석은 문항반응이론(Item Response Theory)을 적용하였다. 결과 한국인에서 DSM-IV의 주요우울장애 진단 기준의 오류는 없었으나, 진단 기준의 역치는 높았다. 한국인이 호소하는 우울증상으로서 "피로감"과 "집중력 저하", "수면 변화"는 진단되는 우울증의 초기부터 잘 나타나는 증상 들이며, "정선운동변화", "죽음/자살사고", "무가치함/죄책감"은 보다 심한 우울증에서 잘 나타나는 증상들이었다. 결론 DSM-IV가 제시하는 주요우울장애 진단 기준은 한국인의 우울증을 평가하는 데 있어 타당하기는 하나, 진단 기준의 역치가 높다. 우울증의 중증도에 따라 호소하는 증상들이 달랐다. Baekgrounds : Many Korean epidemiologic studies reported lower prevalence rates of depression than those of Western countries. For the low prevalence, it is explained that there's something wrong in the direct application of diagnostic criteria of depression to Korean culture, i.e. categorical fallacy, or it may be truly low-prevalent. We will analyze diagnostic criteria for depression detined by Western. Methods : Six thousand and two hundred seventy-five cummunity dwelling subjects, aged 18-64 years were interviewed by using Korean version of Composite International Diagnostic Interview (K-CIDI). Diagnostic criteria for depression defined by DSM-IV were analyzed using the item response theory. Rcsults : We could not find any fallacies of diagnostic critcria tbr depression defined by DSM-IV when assessing depre-ssion among Koreans. Fatigue, concentration difficultics, and sleep disturbance appeared more fequently in mild depression, while psychomotor change, death/suicide, and worthlessness/guilt did not appear until severe depression. Cunclusion : The diagnostic criteria for depression defined by DSM-IV arc appropriate for the Koreans. There are different responding levels, i.e. threshold, of depressive criteria according to severities of depression. Koreans with depression are more likely to complain of appetite change, but less of worthless or guilty feelings than Western people.

9-12%Cr강의 첨가원소 및 열처리에 따른 미세조직거동과 경도변화

주성욱,유정훈,신기삼,허성강,이재현,석진익,김병훈,김정태 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

9-12%Cr steel are getting increasing attention for expanded application as high temperature materials applicable for gas turbine compressors, steam turbine rotors, blade and casing. For efficient and extensive application of 9-12%Cr steel, the data in addition to the improvement of mechanical properties on the correlation of microstructural evolution and mechanical properties are inevitable and thus the investigation in this study is performed for the determination for the specimens heat-treated at 600, 650 and 700℃ for 1000, 3000 and 5000hrs. The microstructure of as-received specimen was tempered martensite, with a high dislocation density and secondary phases. Upon high temperature heat-treatment, the martensite lath got larger and dislocation density decreased resulting the reduction of the strength. In addition, sharp growth of secondary phases was observed in the specimen heat-treated at 700℃ for 5000hrs. A specimen aged at 600℃ and 650℃ Laves phase was observed. The hardness showed close relationship with the secondary phase particle and dislocation density.

정상 성인에서 갈근(Radix puerariae)의 장기투여가 혈중 알콜 농도에 미치는 영향

박제민,김지훈,김명정,김성곤,정영인 大韓神經精神醫學會 1996 신경정신의학 Vol.35 No.6

알콜 의존에서 알콜 소비량을 감소시키고 음주 재발을 방지하는데 효과가 있다는 약물들이 몇 가지 있으며 갈근이 알콜 의존증의 치료에 효과가 있다는 자료들이 있다. 저자들은 정상 성인을 대상으로 알콜을 섭취하게 한 후 갈근 투여 전, 후의 혈중 알콜 농도를 비교함으로써 갈근이 알콜 대사를 방해하여 혈중 알콜 농도를 상승시키는지를 검증하고자 하였다. 알콜을 비롯한 약물 남용이나 의존증이 있거나 기타 정신 질환이 없고 주요 신체질환이 없는 20∼29세 남자 의과 대학생들을 대상으로 하였다. 대상자는 모두 25% 알콜을 3ml/kg(100%알콜 0.75ml/kg)을 마시게 한 후 투여 전, 투여 후 10, 30, 60, 90, 그리고 120분에 혈중 알콜 농도를 측정하게 한 다음 14일간 갈근 하루 6g을 투여한 후 첫날과 같은 방법으로 알콜을 복용하게 한 후 알콜 혈중 농도를 측정하여 약물 투여 전, 후의 알콜 혈중 농도를 비교한 결과 갈근 투여 후에 음주시 30, 60, 90, 그리고 120분에 혈중 알콜 농도가 유의하게 상승하였다. In alcohol dependence, some drugs reduce alcohol consumption and prevent the recurrence of alcohol drinking. There were some evidences that Radix puerariae was effective in the treatment of alcohol dependence. We studied the effect of Radix puerariae on blood alcohol concentration in healthy adults. The subjects were medical students, who did not have major physical disorders, drug abuse or dependence including alcohol, and other psychiatric disorders. After drinking 25% alcohol 3ml/kg, all subjects were measured for blood alcohol concentration at 0, 10, 20, 30, 45, 60, 120 minutes by Alco-sensor Ⅳ. Next day, all subjects were made to take Radix puerariae 6g/day(3g bid) for 14 days. And then blood alcohol concentration were measured by the same method. The results were significant increase in blood alcohol concentration at 30, 60, 90 and 120 minutes.

전산유체 기법을 이용한 DAF 부상조에서의 수리 특성 고찰

김성훈,유제선,김영미,박희경 대한상하수도학회 2002 상하수도학회지 Vol.16 No.4

Dissolved air flotation is a solid-liquid separation process that uses fine rising bubbles to remove particles in water. DAF is found most effective in treating algae and lower density flocs that are hard to remove in sedimentation process. Some researcher reports the results of an experimental study which examined the flow within the flotation zone of a DAF tank (ONeill at al., 1997). I would be concluded that, in general, the flow within flotation zone is robust and that differences in the performance of individual DAF tanks must be the result of processes occurring within the contact zones of these tank, not as the result of flotation processes. In this research, the authors thought that the efficiency of the DAF process is strongly related to bubble size. It means bubble rising velocity at the air injection nozzle is most important factor of DAF process. However, bubble movement in DAF tank is somewhat complicate, so it is hard to make up conceptual model through simple mass balance as other researchers did (Leppinen at. al., 2000). For the modeling of turbulent 2-phase flow in the tank, the standard k-ε model was used in CFD code because it is widely accepted and the coefficients for the model are well established. This model uses the eddy-viscosity hypothesis for the turbulence. As the result of this study, the authors concluded that bubble size and its rising velocity is very important factor of DAF process and the recycle ratio must be also consider for the flotation zone parameter. Also, For the improved model, relation between turbulent intensity and bubble-particle attachment must be studied.

전산유체 기법을 이용한 용존공기부상법에서의 접촉도 조건변화에 따른 충돌효율평가

김성훈,유제선,박희경 대한상하수도학회 2004 상하수도학회지 Vol.18 No.2

Dissolved air flotation (DAF) is a solid-liquid separation process that uses fine rising bubbles to remove particles in water. Most of particle-bubble collision occurs in the DAF contact zone. This initial contact considered by the researchers to play a important role for DAF performance. It is hard to make up conceptual model through simple mass balance for estimating collision efficiency in the contact zone because coupled behavior of the solid-liquid-gas phase in DAF system is 90 complicate. In this study, 2-phase(gas-liquid) flow equations for the conservation of mass, momentum and turbulence quantities were solved using an Eulerian-Eulerian approach based on the assumption that very small particle is applied in the DAF system. For the modeling of turbulent 2-phase flow in the reactor, the standard k-ε mode Ⅰ(liquid phase) and zero-equation(gas phase) were used in CFD code because it is widely accepted and the coefficients for the model are well established. Particle-bubble collision efficiency was calculated using predicted turbulent energy dissipation rate and gas volume fraction. As the result of this study, the authors concluded that bubble size and recycle ratio play important role for flow pattern change in the reactor. Predicted collision efficiency using CFD showed good agreement with measured removal efficiency in the contact zone. Also, simulation results indicated that collision efficiency at 15% recycle ratio is higher than that of 10% and showed increasing tendency of the collision efficiency according to the decrease of the bubble size.