급성내경동맥폐쇄로 인한 제3뇌신경 불완전마비를 동반한 안동맥폐쇄

안재환,이슬기,김현웅,Jae Hwan Ahn,MD,Sul Gee Lee,MD,Hyun Woong Kim,MD 대한안과학회 2009 대한안과학회지 Vol.50 No.4

Purpose: We report a case of ophthalmic artery occlusion with third nerve paresis in the left eye due to acute occlusion of the left ICA. Case summary: A 37-year-old man visited our emergency room with “black out” in the left eye, headache, and nausea. The corrected visual acuity was 20/25 in the right eye, and hand motion in the left eye. In the left eye, a relative afferent papillary defect was noted, with an intraocular pressure of six mmHg. Twenty prisms of exotropia in the primary position was observed, and ocular motor examination revealed limitations of supraduction, infraduction, and adduction in the left eye, suggesting third nerve palsy of the left eye. Fundus examination revealed a pale retina in the macula of the left eye. Brain MRI demonstrated multifocal faint low densities in the left caudate nucleus as well as the frontal and parietal lobes. CT angiography and four-vessel angiography demonstrated complete occlusion in the proximal part of the left internal carotid artery ICA. After five months the corrected visual acuity of the left eye improved to 20/200. The 20 prism diopters of exotropia persisted, and ocular motor examination revealed only a mild limitation of adduction in the left eye. J Korean Ophthalmol Soc 2009;50(4):624-629

특집 제2차 과학기술기본계획-(4) 과학기술인력 양성.활용

안재환,An, Jae-Hwan 한국과학기술단체총연합회 2008 과학과 기술 Vol.41 No.3

교수 계약임용제도 운영 사례-아주대학교 계약제 교수 임용을 중심으로-

안재환,An, Jae-Hwan 한국대학교육협의회 1999 大學敎育 Vol.99 No.-

단안 선천 상사근마비 환자에서 하사근절제술, 후전술, 전치술의 효과 비교

안재환,이슬기,Jae Hwan Ahn,Sul Gee Lee 대한안과학회 2010 대한안과학회지 Vol.51 No.1

Purpose: To compare the clinical outcomes of myectomy, recession, and anterior transposition (AT) of the inferior oblique muscle in congenital unilateral superior oblique palsy. Methods: A total of 40 patients who were followed for longer than three months postoperatively and, who underwent inferior oblique myectomy, recession, or AT were evaluated retrospectively. Results: We compared the result of inferior oblique myectomy, recession, and AT in congenital unilateral superior oblique palsy. The decreased amounts of inferior oblique overaction (IOOA) were 2.24±0.67, 2.00±0.76, 3.00±1.15 for myectomy, recession, and AT, respectively. Improvement of superior oblique underaction was 0.80±0.66, 0.86±0.83, 1.00±0.58, and the changes in hyperdeviation were 10.96PD, 8.25PD, 14.86PD for myectomy, recession, and AT, respectively. There were no significant differences among the surgical methods. The proportion of patients who showed IOOA in the contralateral eye after operation were 20.0% in myectomy, 25.0% in recession, and 57.1% in AT. Conclusions: The efficacies of myectomy, recession, and AT of inferior oblique muscle in the congenital unilateral superior oblique palsies showed no significant differences among methods. The AT group tended to show a larger effect than did the other methods, along with a high development percentage of contralateral eye IOOA. Based on these results, AT of the IO shoud be selectively chosen in more severe cases. J Korean Ophthalmol Soc 2010;51(1):76-80

퇴적물 준설에 따른 수환경 영향 예측 모의

안재환(Jae Hwan Ahn),김미경(Mee Kyung Kim),이미경(Mi Kyung Lee),황병기(Byung Gi Hwang) 大韓環境工學會 2005 대한환경공학회지 Vol.27 No.11

VFSMOD를 이용한 경작지의 고형물질 유출 저감효과

안재환(Jae Hwan Ahn),윤상린(Sang Leen Yun),김석구(Seog Ku Kim),박윤식(Youn Shik Park),임경재(Kyoung Jae Lim) 大韓環境工學會 2012 대한환경공학회지 Vol.34 No.12

본 연구는 남한강과 북한강 유역 내 경작지 각 3개소(site A, B, C)를 대상으로 Web GIS-based VFSMOD System의 HUFF & SCS UH-based VFS Design Module을 적용하여 강우 시 경작지에서 유출되는 고형물질 유출저감을 모의하였다. 북한강 유역 내에 위치한 site A의 노지 밭의 토지경사도 5%, 강우 106.2mm 조건에서 고추 및 옥수수를 재배할 경우, 70% 이상의 고형물질 유출저감 효율을 얻기 위해서는 초생대 폭이 최소 0.5m 이상, 토지경사도 10%인 경우 70% 이상의 고형물질 유출저감 효율을 얻기 위해서는 초생대 폭이 최소 1.0∼1.5m 이상 유지해야 한다. 남한강 유역 내에 site B의 노지 밭의 토지경사도 5%, 강우량 95.1mm 조건에서 토마토 및 땅콩을 재배할 경우, 70% 이상의 고형물질 유출저감을 위해서는 초생대의 폭이 최소 0.5m, 토지경사도 10%인 경우 50% 이상의 고형물질 유출저감을 위해서는 최소 1.0m 이상의 폭을 갖는 초생대를 설치 해야 하는 것으로 나타났다. 남한강 유역 내에 site C의 노지 밭의 토지경사도 5%, 강우량 102.6mm 조건에서 고구마 및 콩을 재배할 경우, 64.0% 이상의 고형물질 유출저감을 위해서는 초생대의 폭이 최소 1.0m, 초생대를 설치해야 하는 것을 분석 되었다. 또한, 동일한 조건에서 강우지속시간 2시간의 강우량을 151.2mm로 증가시킬 경우, 62.0% 이상의 고형물질 유출저감을 위한 초생대의 최소 폭은 1.0m 이상 설치해야 하는 것으로 분석되었다. 초생대 시설은 경작지와 같은 토지이용 시 친환경적인 고형물질 유출저감 방안으로 검토될 수 있으며, Web GIS-based VFSMOD System을 이용하여 다양한 토지특성과 강우 사상을 반영하여 적정한 규모의 초생대 설계가 가능할 것으로 분석되었다. The study was performed to simulate the reduction efficiency of suspended solids (SS) for cultivated land located at riverine area at the Namhan River and the Bukhan River watershed sites (site A, B, C) under the rainfall conditions using HUFF & SCS UH-based VFS Design module of Web GIS-based VFSMOD System. The study indicates that the field 5% sloped, located at Bukhan River watershed (site A), requires at least 0.5m width of Vegetative Filter Strip (VFS) to reduce 70% of SS while the field 10% sloped requires the at least 1.0∼1.5m width of VFS to reduce 70% SS, under the condition 106.2mm of rainfall event and bell pepper or corn of crops. Against the conditions 95.1mm of rainfall event and sweet potato or soy bean of crops, the field 5% sloped, located at Namhan River watershed (site B) requires at least 0.5m width of VFS to reduce 70% of SS while the field 10% sloped requires at least 1.0m width of VFS to reduce 50% SS. The crops sweet potato and soy bean are cultivated in the site C, located at Namhan River watershed, 1m of VFS is capable of 64.0% and 62.0% of SS reduction against 102.6mm and 151.2mm rainfall conditions respectively, for the 5% sloped field. The result supports that VFS is one of most potential methods to reduce SS from cultivated area, which is environment-friendly hydrologic structure. The VFS design, however, needs to be simulated before its installation in the field, the simulation needs to consider not only various characteristics of the field but also different conditions affecting the VFS, using a model capable to consider a lot of factors.

실험실 규모의 음향정재파를 이용한 수중의 입자분리 특성

안재환(Jae Hwan Ahn),강성원(Sung Won Kang),안광호(Kwang Ho Ahn),김이태(I Tae Kim),김석구(Seog Gu Kim),안호상(Ho Sang Ahn),이영섭(Young Sup Lee) 大韓環境工學會 2012 대한환경공학회지 Vol.34 No.12

실험실 규모의 음향정재파 장치를 이용하여 수체에 포함된 입자의 분리특성을 알아보았다. 음향정재파는 음파 또는 초음파와 유사한 파장으로 반사벽에 의해 발생된 파가 돌아오면서 일정한 파장을 형성한다. 이때 수중에 분산되어 있던 미세한 입자들은 음압이 0인 파장의 절점(node) 부분에 모이게 된다. 주파수 28.0kHz와 1.0MHz의 음향정재파 트랜스듀서를 이용 하였고, 수체에 포함된 입자는 평균 입경 6.8μm의 카올린과 100.5μm의 레드머드를 사용하였다. 수체 내에 음향정재파가 형성되면 발생된 파장에 의한 음압으로 수온이 0.15∼0.20℃/min 정도 상승된다. 카올린과 레드머드의 초기 농도는 0.1, 0.2, 0.3, 0.4, 0.5g/L로 동일하게 제조하였다. 1.0MHz의 주파수에서 5분경과 후 음향정재파가 가장 뚜렷하게 형성되었을 때의 반응조내의 탁도 제거율은 카올린은 18.2%∼56.2%로, 입경이 큰 레드머드는 23.0%∼53.6%의 분리효율을 나타내었다. 28.0kHz 주파수에서는 입자분리가 이루어지지 않았다. Characteristics of particle separation in water using labscale acoustic standing wave were studied. Acoustic standing wave is similar to either sound wave or ultrasonic, which makes a constant wave while returning to the origin by reflector. During that time, particulates dispersed in water are collected on the node of wave, where a sound pressure is zero. Acoustic standing wave transducer as of 28.0kHz and 1.0MHz were utilized and 6.8μm kaolin and 100.5μm redmud in average diameter were used as experimental materials in water. Once acoustic standing wave are generated in water, water temperature rises by 0.15∼0.20℃/min due to a sound pressure. Initial concentration of kaolin and redmud were controlled to have same as of 0.1, 0.2, 0.3, 0.4, 0.5g/L, respectively. Removal efficiency of the turbidity in a reacting chamber after 5 minutes, when acoustic sound wave was formed in most distinct, was measured to have 18.2∼56.2% for kaolin and 23.0∼53.6% for redmud at 1.0MHz. Particle separation was not observed at 28.0 kHz.

혐기성 소화효율 향상을 위한 초음파를 이용한 슬러지 전처리 및 ADM1 모의

안재환(Jae Hwan Ahn),김미경(Mee Kyung Kim),배재호(Jae Ho Bae),김희준(Hee Jun Kim) 大韓環境工學會 2007 대한환경공학회지 Vol.29 No.1

저임계 열적산화공법에 의한 슬러지 감량화

안재환(Jae-Hwan Ahn),김미경(Mee-Kyung Kim),이미경(Mi-Kyung Lee) 한국유체기계학회 2006 유체기계 연구개발 발표회 논문집 Vol.- No.-

Sludge reduction by the sub-critical wet air oxidation (SCWAO; at <250℃ and 30 atm) was studied to find out the optimal operational parameters such as time, temperature, pressure, and oxidant dose. The initial suspended solids (SS) and total chemical oxygen demand (TCOD) concentrations of sludge used for the laboratory-scale experiment were 6,500 and 7,500 ㎎/L, respectively. When the temperature changed from 180 to 260℃ with 20℃ intervals, higher temperature was shown with higher TCOD removal efficiency at around 75%, and the soluble chemical oxygen demand (SCOD) was increased abruptly up to 2,000 ㎎/L within 10 min. At the same time, SS was decreased as SCOD increasing, implying organicsolids were liquefied during the process, with about 70% of SS decomposed within 10 min, whereas the organic acid concentration increased rapidly within 20 min. The higher temperature also resulted in higher organic acid concentration. Based on the results from the lab-scale experiments, a pilot plant with the capacity of 3 ㎥/d was designed and then operated at 60 min hydraulic retention time (HRT), 220℃, and <30 atm. Air was injected into the WAO reactor for the higher oxidation efficiency, at the flow rate of 50% of the stoichiometric oxygen requirement. The removal efficiencies for total solids and TCOD at 220℃, 30 atm, and 60 min HRT were over 70% and 40%, respectively, and the yields of volatile fatty acids (VFAs) and SCOD were 115 g VFAs/㎏ SS and 730 g SCOD/㎏ SS, respectively.

슬러지처리 : 습식산화에 의한 하수슬러지에 포함된 영양염류의 변화

안재환 ( Jae Hwan Ahn ),박인숙 ( In Sook Park ),홍준식 ( Joon Sik Hong ),조완선 ( Wan Seon Cho ) 대한상하수도학회 2003 공동추계 학술발표회 논문집 Vol.2003 No.-