10~30대 정상인에서의 상대구심성동공운동장애

이인범,최병훈,문연성,황정민,In-Bum Lee Candidate,Byung-Hun Choi Candidate,Yeon-Seong Mun,Jeong-Min Hwang 대한안과학회 2005 대한안과학회지 Vol.46 No.6

Purpose: In order to investigate the incidence of relative afferent pupillary defect (RAPD) in normal adolescence and if there is any interocular difference in the case with RAPD. Methods: Fifty-eight adolescence in 14 to 36 years of age who showed normal findings on measurement of visual acuity, intraocular pressure, slit lamp examination, and funduscopic examination except refractive errors underwent swinging flashlight test and infrared pupillography. The case with RAPD further underwent optical coherence tomography, color vision test, Humphrey visual field test, and Bryngelson test (hole-in-the-card test). Results: One out of 58 cases, in whom more pronounced myopic astigmatism and lower mean deviation on Humphrey visual field test within normal limits were found, showed RAPD in the dominant right eye with swinging flashlight test and infrared pupillography. Conclusions: The incidence of RAPD in normal adolescence was 1.7%. Myopic astigmatism was higher in the eye with RAPD.

TPV 효율 향상을 위한 태양전지판의 각도 및 방향 제어에 관한 연구

이인범(In Bum Lee),전성훈(Sung Hoon Jun),이응기(Eung Ki Lee) 한국생산제조학회 2012 한국생산제조시스템학회 학술발표대회 논문집 Vol.2012 No.4

류마티스 관절염의 질병활성도 지표로써 모발의 미세원소 농도

전재범 ( Jae Bum Jun ),김태환 ( Tae Hwan Kim ),김승영 ( Seung Young Kim ),김평남 ( Pyoung Nam Kim ),정성수 ( Sung Soo Jung ),이인흥 ( In Hong Lee ),배상철 ( Sang Cheol Bae ),유대현 ( Dae Hyun Yoo ),주경빈 ( Kyung Bin Joo ),김성윤 대한류마티스학회 1995 대한류마티스학회지 Vol.2 No.1

연구 배경: 아연과 구리는 인체에서 두번째와 세번째로 많이 존재하는 미세원소로, 면역기능에 관계하는 것으로 알려져 있다. 류마티스 관절염은 대표적인 자가면역성 질환으로 혈청 아연은 감소하고 혈청 구리는 증가한다고 한다. 최근 미세원소를 모발에서 측정하는 연구가 많은데, 이는 모발이 갖는 여러가지 장점때문이다. 그러나 류마티스 관절염 환자의 모발에서 미세원소를 측정한 연구는 없다. 저자들은 류마티스 관절염 환자의 모발에서 미세원소를 측정하고 질병 활성도와의 연관성을 알아보고자 한다. 방법: 류마티스 관절염 환자 50명과 퇴행성 관절염 환자 22명을 대상으로 유도결합플라즈마 원자방출분광법으로 모발의 아연과 구리농도를 측정하였다. 결과: 1) 구리의 농도는 류마티스 관절염 환자에서 15.42±6.29 ppm이었고, 퇴행성 관절염 환자에서는 15.41±7.49 ppm (p>0.05)으로 유의한 차이를 보이지 않았다. 아연의 농도도 각각 197.59±80.18ppm, 201.14±60.68 ppm(p<0.05)으로 유의한 차이를 보이지 않았다. 2) 질병활성도를 나타내는 여러가지 지표들과 류마티스 관절염 환자 모발의 미세원소 농도는 유의한 연관성을 보이지 않았다. 결론: 류마티스 관절염 환자 모발의 미세원소는 퇴행성 관절염 환자의 미세원소 농도와 유의한 차이가 없었으며, 질병활성도를 나타내는 지표와 의미있는 연관성을 보이지 않아 질병활성도의 지표로는 유용하지 않을 것으로 사료된다. Objective: Zinc and copper are the second and third most abundant trace elements following iron in the human body. Zinc and copper have important effects on humoral and cell-mediated immunity. In patients with rheumatoid arthritis, it has been reported that serum zinc level is decreased and seurm copper level increased. But no reports are available for the trace element level of hair in patients with rheumatoid arthritis. We studied to investigate the significance of trace element level of hair in rheumatoid arthritis patients, particularly its relation to disease activity. Methods: The trace element level of hair was estimated in 50 patients with rheumatoid arthritis and 22 osteoarthritis patients by inductively coupled plasma atomic emission spectrometry and was investigate the correlation to various disease activity indices of rheumatoid arthritis. Results: The results were as follows: 1) There was no significant difference in either the zinc or copper level in hair between patients with rheumatoid arthritis and osteoarthritis. 2) No correlation was observed between the zinc or copper level in hair and age or disease duration for rheumatoid arthritis patients. 3) Zinc and copper levels of hair did not correlate with various indices of disease activity in rheumatoid arthritis patients. Conclusions: Zinc and copper levels of hair in rheumatoid arthritis patients were not different from those of osteoarthritis and did not correlate with disease activity indices. Studies on the effect of antirheumatic drug therapy on trace element level of hair are necessary.

Numerical visualization of mixing in a circular chamber by two opposite impinging jets

Hamidreza Karbasian(하미드 카바시안),Youngwoo Kim(김영우),In Bum Lee(이인범),Beom Jeong Han(한범정),Yong Chai Jeong(정용채),Kyung Chun Kim(김경천) 한국가시화정보학회 2016 한국가시화정보학회지 Vol.14 No.3

In this study, the mixing process of two distinct flow is numerically investigated. Two flow with different physical properties (resin and hardener) are mixed through the opposing mixing jets. At a high pressure mixing process, the high speed flow is provided by two in-line nozzles. In the case of numerical modeling, Reynolds-Averaged Navier-Stokes Equations (RANS) is conducted to model the flow pattern inside the chamber. Additionally, SST k-omega turbulence model is selected to predict the kinetic energy of flow in impingement zone. The results show that mixing of two distinct flows would be efficient if the velocity of jet is high enough and nozzle diameter is a predominant parameter. Also, this velocity would create higher shear stress between two distinct flows which increases the mixing quality as well as strength of formed vortices. Eventually, the histogram of concentration fraction of resin is examined in order to show the quality of mixing and the range of concentration fractions in the output of chamber.

Phospholipase C-γ Activation by Direct Interaction with β-Tubulin Isotypes

이인범,김성국,최장현,서판길,장종수,Lee, In-Bum,Kim, Sung-Kuk,Choi, Jang-Hyun,Suh, Pann-Ghill,Chang, Jong-Soo Korean Society of Life Science 2006 생명과학회지 Vol.16 No.4

Phosphoinositide-specific phospholipase $C-{\gamma}\;1\; (PLC-{\gamma}\;1)$ has pivotal roles in cellular signaling by producing second messengers, inositol 1,4,5-trisphosphate $(IP_3)$ and diacylglycerol (DG). Tubulin is a main component of microtubules and mitotic spindle fibers, which are composed of ${\alpha}-$ and ${\beta}-tubulin$ heterodimers in all eukaryotic cells. In humans, six ${\beta}-tubulin$ isotypes have been identified which display a distinct pattern of tissue expression. Previously we found that $PLC-{\gamma}\;1$ and one of four ${\beta}-tubulin$ isotypes including ${\beta}1$, ${\beta}2$, ${\beta}3$ and ${\beta}6$, colocalized in COS-7 cells and cotranslocated to the plasma membrane to activate $PLC-{\gamma}\;1$ upon agonist stimulation. In the present study, we demonstrate that the remaining two, tubulin ${\beta}4$ and ${\beta}5$, also showed a potential to activate $PLC-{\gamma}\;1$. The phosphatidylinositol 4,5-bisphosphate $(PIP_2)$ hydrolyzing activity of $PLC-{\gamma}\;1$ was substantially increased in the presence of purified ${\beta}4$ and ${\beta}5$ tubulin in vitro, whereas the activity was not promoted by bovine serum albumin, suggesting that tubulin ${\beta}4$ and ${\beta}5$ also activate $PLC-{\gamma}\;1$. Taken together, our results suggest that all the ${\beta}-tubulin$ isotype activates $PLC-{\gamma}\;1$ activity to regulate cellular signaling. 포스포리파제 C-감마1$(phospholipase\;C-{\gamma}\;1;\;PLC-{\gamma}\;1)$은 활성화될 경우 세포 내의 이차전령인 inositol 1,4,5-trisphosphate$(IP_3)$와 diacylglycerol(DG)을 생성하는 중요한 세포 신호전달 분자이다. 튜불린은 미세소관과 방추사의 주요 구성 단백질로서 알파형과 베타형의 두 가지 동위형이 있는데 이들은 모든 진핵세포에 존재하면서 이형 이합체를 형성한다. 이 중 베타형 튜불린은 사람의 경우 6종의 또 다른 동위형이 존재하는 것으로 밝혀졌는데 이들은 각 조직에서 그 발현양상이 서로 다르게 나타난다. 이전의 연구에서 우리들은 $PLC-{\gamma}\;1$과 4종의 베타튜불린 동위형 즉, ${\beta}1$, ${\beta}2$, ${\beta}3$ 및 ${\beta}6$이 세포 내에서 서로 결합할 수 있으며 또한 외부의 자극이 전달될 경우 이들 4종의 동위형이 $PLC-{\gamma}\;1$을 활성화시켜 준다는 사실을 보고한 바 있다. 이번 실험에서는 이전의 연구에서 조사하지 못하였던 베타 튜불린의 나머지 두 가지 동위형 즉, ${\beta}4$및 ${\beta}5$가 $PLC-{\gamma}\;1$에 결합하여 $PLC-{\gamma}\;1$의 활성을 증가시켜줌으로서 세포 내에서의 신호전달계를 조절하고 있음을 확인하였다. 이 결과는 이전의 연구결과와 연관 지워볼 때, 6종의 모든 베타형 튜불린은 세포 외부의 자극이 있을 경우 $PLC-{\gamma}\;1$을 활성화시켜줌을 시사한다.

5MW 풍력용 피치드라이브의 유성기어 Micro-geometry 최적화에 관한 연구

이인범(In-Bum Lee),김동영(Dong-Young Kim),허철수(Zhe-Zhu Xu),이도영(Do-Young Lee),류성기(Sung-Ki Lyu) 한국기계가공학회 2014 한국기계가공학회지 Vol.13 No.1

The rotation of a spindle unit must be accurate for high-quality machining and to improve the quality of the machine tools. Therefore, the proper measurement of the rotation accuracy and ensuring a proper analysis are very important. Separate processes are necessary because spindle errors and roundness errors associated with the test balls can both factor into the measured rotation error values. We used three methods to discern test ball errors and analyzed which could be deemed as the most proper technique in a test of the rotation accuracy of the main spindle of a machine tool.

탄산을 첨가한 슬러리 쉴드 터널에서의 침투 거동 및 굴진면 안정성 평가

이익범,최기훈,이인모,Lee, Ik-Bum,Choi, Ki-Hoon,Lee, In-Mo 한국터널지하공간학회 2013 한국터널지하공간학회논문집 Vol.15 No.4

최근 연약지반 터널 현장에 활용되는 슬러리 쉴드 TBM은 굴진면으로 슬러리가 주입됨으로 그 안정성을 확보하는 공법이다. 하지만 간극이 과다하여 슬러리에 의한 폐색이 발생하지 않는 조립질 지반에서는 적용이 어렵기 때문에 첨가제를 혼입하여 사용하기도 한다. 본 연구에서는 첨가제의 역할로서 탄산가스를 주입함으로 슬러리가 주입되었을 때에 간극 내에 탄산가스가 흡착하여 폐색현상을 촉진시키는 효과를 규명하였다. 실내실험 결과 탄산 혼입에 따라 슬러리 쉴드 터널이 적용 가능한 유효입경이 1.0 mm에서 2.6 mm가량으로 증가하였고, 필터계수 ${\lambda}$가 $0.007sec^{-1}$이상인 경우에 탄산에 의한 효과가 발생함을 알 수 있었다. Slurry shield tunnelling ensures stability by pressurizing the tunnel face with the slurry contained in the chamber. It resists water and earth pressure in order to prevent the failure in the tunnel face during tunnel excavation. If the ground is relatively coarse, slurry can not clog the tunnel face and excessive slurry infiltration will occur. In this case chemical compounds or additives should be added to the slurry in order to improve the clogging phenomena at the tunnel face. In this study, the effect of the carbon dioxide gas as an additive to the slurry instead of chemical compounds on the capability of enhancing the clogging in the tunnel face is investigated. Bubbles arising from the carbonate-added slurry are trapped in the soil voids enhancing the clogging capability. This effect is studied in this paper by performing laboratory model tests simulating in-situ conditions, and by adopting the fine particle clogging theory. Tunnel face stability analysis was also performed and it was found that the effective size ($D_{10}$) of soils which can guarantee tunnel stability utilizing the carbonate-added slurry increased from 1.0 mm up to 2.6 mm. Moreover, Stability analysis showed that the tunnel face is stable if the ${\lambda}$(deposition coefficient) value is greater than $0.007sec^{-1}$.

Numerical visualization of mixing in a circular chamber by two opposite impinging jets

하미드 카바시안,김영우,이인범,한범정,정용채,김경천,Karbasian, Hamidreza,Kim, Youngwoo,Lee, In Bum,Han, Beom Jeong,Jeong, Yong Chai,Kim, Kyung Chun The Korean Society of Visualization 2016 한국가시화정보학회지 Vol.14 No.3

In this study, the mixing process of two distinct flow is numerically investigated. Two flow with different physical properties (resin and hardener) are mixed through the opposing mixing jets. At a high pressure mixing process, the high speed flow is provided by two in-line nozzles. In the case of numerical modeling, Reynolds-Averaged Navier-Stokes Equations (RANS) is conducted to model the flow pattern inside the chamber. Additionally, SST k-omega turbulence model is selected to predict the kinetic energy of flow in impingement zone. The results show that mixing of two distinct flows would be efficient if the velocity of jet is high enough and nozzle diameter is a predominant parameter. Also, this velocity would create higher shear stress between two distinct flows which increases the mixing quality as well as strength of formed vortices. Eventually, the histogram of concentration fraction of resin is examined in order to show the quality of mixing and the range of concentration fractions in the output of chamber.

SCM420H 유성기어의 연삭효과에 관한 연구

안인효(In-Hyo An),허남수(Nam-Soo Hur),이인범(In-Bum Lee),류성기(Sung-Ki Lyu) 한국기계가공학회 2012 한국기계가공학회지 Vol.11 No.5

This study dealt with effect of the grinding in SCM420H planetary gears. The hardness, tooth profile, lead and roughness of the gear surface can be improved by grinding process. Therein, the grinding techniques are widely used especially as one of the physical surface improvement methods. As the results, the gear grinding process reduced vibration and noise, and increased the life of the gear. And the gear grinding improved the surface of gear tooth in a short time and low cost, thus, it is a very important process in manufacturing industry. But nowadays, it is hard to find the detail information of gear grinding process. The test piece is a planetary gear which is used in the industrial machine. The manufacture process of the test piece contains hobbing, shaving, carburizing and grinding. This study investigated the effect of the grinding process to the physiognomy and the fatigue strength of test piece which was made by SCM420H.

5MW 풍력용 Pitch Drive 구성품의 부하에 관한 연구

김동영(Dong-Young Kim),이인범(In-Bum Lee),양용군(Long-jun Liang),류성기(Sung-Ki Lyu) 한국기계가공학회 2014 한국기계가공학회지 Vol.13 No.1

Wind power is a type of clean energy source which does not produce carbon dioxide. The wind turbine industry is considered as a major growth industry in many countries. The main cause of wind turbine failure arises in the wind turbine gearbox, and the main type of damage occurs in the bearings and gears. Therefore, predictions ofgear and bearing damage are very important to ensurethe reliability of the wind turbine reducers used in these systems. In this research, in order to optimize the wind turbine reducer, a series of simulations and redesigns was done using the tool RomaxDesigner. The RomaxDesigner model was used to analyze the bearing life of the duty cycle for a 5 MW wind-turbine pitch drive and to calculate the load in operating states. The reducer was designed to satisfy the life requirement by analyzingbearing damage and calculating the stress values of the main parts of the reducer.