사출기 유압 시스템 분석용 해석 모델 개발

윤영환,노대경,장주섭,전윤선,어승룡 유공압건설기계학회 2013 유공압건설기계학회 학술대회논문집 Vol.2013 No.6

한 개의 지중 전열선에 의한 열전달 분포에 관한 연구

윤영환,전계웅 산업기술연구소 1999 産技硏論文集 Vol.13 No.-

화병과 주요우울증 환자의 신경인지기능

윤영환,이소희,최종혁,Yun, Young Hwan,Lee, So Hee,Choi, Jong Hyuck 대한생물정신의학회 2005 생물정신의학 Vol.12 No.2

Objectives:Hwa-byung has been studied clinically for several years and introduced as Korean Culture- Bound Syndrome. However, the definition and the diagnostic method are not yet clarified, and there has not been any sufficient comparative study on this disease entity. This study was conducted to determine the clinical symptoms and the profile of the neurocognitive functions in Hwa-byung(HB) and Major Depressive Disorder(MDD), and We wish to identify any critical factors that differentiate the disorders. Methods:A total of 102 participants were examined, including 34 participants with MDD, 34 with HB, and 34 healthy controls. The MDD and HB patients were recruited from among inpatients and outpatients at the National Medical Center for the period from May to December of 2004. As a major diagnostic tool of MDD, diagnostic reference of DSM-IV-TR was used and as HB's diagnostic tool, We used computerized neurocognitive function test. Psychiatric symptomatology was evaluated by the Beck Depression Inventory(BDI), and Symptom Checkist-90-Revision(SCL-90-R). Oneway ANOVA, Scheffe post-hoc test and Chi-Squre Tests were used for statistical analysis. Results:The participants in three groups did not differ in terms of age, sex, and education. Assessment of BDI indicated that the MDD group had significantly higher total score than the HB group. MDD and HB groups showed significantly higher total scores on the SCL-90-R in comparison to the controls. The MDD group was found to have significantly more symptoms of depression than the HB group, based on the depression subscale of the SCL-90-R. The computerized neurocognitive function test suggest several results 1) Within the memory domain, it was found that one of the two memory tests in MDD and HB groups were significantly impaired in comparison to the control group. 2) Within the attention domain, it was found that only the MDD group was significantly impaired in comparison to the control group. 3) Within the higher cortical function domain, it was found that significant impairment exist in MDD group and HB group compared to the control group; the severity of impairment was found to be more profound in the MDD group than in the HB group. Conclusion:These results suggest that both HB group and MDD group have significantly decreased neurocognitive function than the control group, and neurocognitive function of the HB group is better than that of the MDD group.

[병영일기] 김 하사님, 「충성!」

윤영환 샘터사 1999 월간 샘터 Vol.30 No.9

평판 핀 튜브 열교환기의 공기측 강제대류 열전달 계수에 대한 실험 및 수치계산

윤영환,팽진기,윤건식 대한설비공학회 2006 설비공학 논문집 Vol.18 No.9

Air-side forced convective heat transfer of a plate fin-tube heat exchanger is investigated by experimental measurement and numerical computation. The heat exchanger consists of staggered arrangement of refrigerant pipes of 10.2mm diameter and the pitch of fins is 3.5mm. In the experimental study, the forced convective heat transfer is measured at Reynolds number of 1082, 1397, 1486, 1591 and 1649 based on diameter of refrigerant piping and mean velocity. Average Nusselt number for the convective heat transfer coefficient is alsocomputed for the same Reynolds number by commercial software of STAR-CD with standard turbulent model. It is found that the relative errors of average Nusselt numbers between experimental and numerical data are less than 6 percentage in Reynolds number of 1082∼1649. The errors between experiment and other correlations are ranged from 7% to 32.4%. But the correlation of Kim at al is closest to the experimental data within 7% of the relative error.

AMESim Software 소개

윤영환,Yoon Y.H. 유공압건설기계학회 2005 드라이브·컨트롤 Vol.2 No.1

벼 생육중기 및 출수기 태풍 "올가" 건풍에 의한 엽신 피해의 품종간 차이와 수량 및 품질 변화

윤영환,김정곤,정남진,곽강수,강양순 한국국제농업개발학회 2003 韓國國際農業開發學會誌 Vol.15 No.4

1999년 8월3일~8월4일간 태풍 올가 도래시 건풍에 의한 생육중기 엽신 피해의 품종간 차이와 출수기 이삭 갈변에 따른 수량 및 품질에 미치는 영향을 조사하여 다음과 같은 결과를 얻었다. 1. 잎의 증산량 및 수분저하속도가 클수록, 잎이 길이가 길고 폭이 넓을수록 엽신의 피해정도가 컸다. 2. 이삭의 피해 정도가 증가될수록 임실 및 등숙비율은 현저히 낮아지는 경향이며, 쌀 수량은 무피해 대비 피해 3~5는 14~16%, 피해 7은 28%, 피해 9는 48% 감수하였다. 3. 이삭의 피해 정도별 백미 완전미 비율은 피해 정도가 클수록 감소를 보였으며 피해 0~3에서 63~65%, 피해 5~9에서 42~58%의 분포를 보였다. 4. 이삭의 피해정도가 증가할수록 백도 및 색도치가 낮아지며, 단백질 함량은 증가하고 식미치는 저하하는 경향을 보였다. This study was carried out to characterize the influence of dry wind by typhoon "Olga" during Aug. 3~Aug. 4, 1999 on the rice plant(Oryza sativa L.). For the purpose, the affection of the dry wind during the mid-growing stage and heading stage on the leaf damage, yield and rice quality were investigated. The extent of the leaf damage increased with the increase of leaf size and transpiration rate, and also with the decrease of moisture content in the leaves. The percentage of fertile grain decreased in proportion to the increase of the extent of the panicle damage. Compared with none-damaged rice plants in the panicle, the milled rice yield decreased by 14~16% in the degree 3~5 of the panicle damage, and 28~48% in the degree 7~9. The percentage of head rice was the same in the both milled and brown rice in the degree 0~3 of the panicle damage. Above the degree 5, however, it decreased with the increase of the panicle damage. The whiteness and lightness decreased in proportion to the increase of the degree in the unhulled, brown and milled rice. And, there was a tendency that the protein content in the milled rice increased but eating quality decreased with the increase of the panicle damage.

곡면 엘보우를 가진 사각덕트 내의 유속측정 및 수치계산에 관한 연구

윤영환,박원구 대한설비공학회 2003 설비공학 논문집 Vol.15 No.11

Fluid flow in a rectangular duct for 90$^{\circ}$ bend elbow with the ratio of 1.5 between its curvature radius and width is measured by 5 W laser doppler velocity meter. The fluid flow is also computed by commercial software of STAR-CD for comparison between measured and computed velocity profiles in the duct. Reynolds numbers for the comparison are 11,643, 19,746 and 24,260. From the comparison, computation of principal velocity components in the duct predicts the experimental data somewhat satisfactorily even though those of minor velocity components and turbulent kinetic energy do not match with the experimental data quite well. K-factor for the bend elbow is computed to be average 0.086 while the equivalent ASHRAE data is 0.07.

열교환기내의 유속분포에 관한 연구

윤영환 國立 昌原大學校 産業技術硏究所 2000 産技硏論文集 Vol.14 No.-

Experimental measurement of velocities in branches of a heat exchanger is performed in order to examine fluid flow distribution in the equipment since un-uniform flow distribution makes hot spots on the heat transfer material or reduced heat transfer coefficients. The measurement apparatus is simplified into a system of a dividing manifold, 8 branches of glass tubes and a combining manifold. Velocities in the glass tubes are measured by Ar-ion LDV system. From the experiments, it is found that uneven flow distributions are obtained as flow rate is increased, on the contrary, the fluid flow in the branches are almost evenly distributed as diameter of manifold is increased with the same flow rate. It is also found that turbulence intensities are increased as diameter of the manifold and flow rate are increased.

산업용 GAS TURBINE의 시운전에 관한 열역학적 SIMULATION 연구

윤영환,김현석 산업기술연구소 1997 産技硏論文集 Vol.11 No.-