운전면허시험 강화에 따른 교통안전 효과 분석 연구

이창민,이철기,이상수,윤일수,Lee, Chang Min,Lee, Choul Ki,Lee, Sang Soo,Yun, Ilsoo 한국ITS학회 2020 한국ITS학회논문지 Vol.19 No.5

2011년 운전면허시험 간소화 제도가 도입된 이후 변별력이 없어 교통안전에 미흡하다는 부정적인 견해가 많았다. 이에 2016년 12월 22일부터 개선된 운전면허시험이 도입되었고 현재까지 운영되고 있다. 따라서 본 연구는 개선된 운전면허시험이 도입된 이후 어떤 효과가 있었으며 무엇이 유효했는지 살펴보고자 교통안전 통계자료 분석, 체감도 조사를 수행하였다. 분석 결과, 현재 시험이 적정한 변별력을 갖췄다고 보여 지며, 과거보다 공정성 체감은 상당 수준 올라온 것으로 인식된다. 실효성 부문에서는 아직까지 운전자의 눈높이를 만족하지 못한 것으로 사료되며, 향후에는 보다 심도 있는 연구와 교통선진국 사례를 검토할 필요가 있다. After the driver test was simplified in 2011, there were criticisms of its inadequate level of safety standards. A new and improved test was adopted in December 2016. This study investigated the impact of the changes to the test on safety, and analyzed traffic safety statistics and sensory evaluations to determine the effect of the improved driving license test. The analysis concluded that the current test has a proper discrimination and that fairness has increased considerably. The analysis also identified measures that, once adopted, will improve the conduct of driver tests. In the future, it will be necessary to conduct more in-depth studies and to review cases of advanced countries.

모과내 기능성 유용성분 용매추출공정의 최적화

전주영 ( Ju Yeong Jeon ),조인희 ( In Hee Jo ),경현규 ( Hyun Kyu Kyung ),김현아 ( Hyun A Kim ),이창민 ( Chang Min Lee ),최용희 ( Yong Hee Choi ) 한국산업식품공학회 2010 산업 식품공학 Vol.14 No.2

본 연구에서는 모과내의 여러 가지 기능성 유용성분을 효과적으로 추출하기 위해서, 모과나무의 익은 열매로 만든 약재인 모과를 사용 하였다. 모과의 기능성 유용성분용매 추출 공정의 최적 조건을 확립하고자 하였다. 모과를 에탄올에 추출하여 반응표면 분석법으로 모니터링하여 최적 용매 조건을 설정하였다. 중심합성계획법에 따라 시료에 대한 용매비(X1)와 추출온도(X2), 추출시간(X3)을 요인변수로 하고 추출수율(Y1), 총페놀 함량(Y2), 전자공여능(Y3), 갈색도(Y4), 환원당(Y5)을 종속변수로 하여 시행하였다. 실험 결과 추출수율은 추출 온도와 추출 시간에 유의하게 영향을 받음을 알 수 있었다. 안장점에서 추출조건은 시료에 대한 용매비는 26.38mL/g, 추출온도는 72.82oC, 추출시간은 74.86 min에서 최대값을 나타내었다. 총페놀 함량은 용매비와 시간에 영향을 거의 받지 않았고 추출시간에는 영향을 받았으며, 최대값은 20.70mg/mL 로 나타났다. 이때의 추출조건은 시료에 대한 용매비는 22.61mL/g, 추출온도는 84.49oC, 추출시간은 77.25 min으로 나타났다. 전자공여능은 추출온도에 따라 유의하게 영향을 받은 것으로 나타났다. 안장점에서의 추출조건인 시료에 대한 용매비 10.65mL/g, 추출온도 67.78oC, 추출시간 96.75 min에서 추출수율은 94.12%로 예측되었다. 갈색도에 대한 추출조건은 시료에 대한 용매비 23.77mL/g, 추출온도 87.27oC, 추출시간 96.68 min 일 때 안장점이 나타났다. 환원당은 시료에 대한 용매비 26.83mL/g, 추출온도 82.167oC, 추출시간 81.94 min에서 10.55mg/mL로 최대값을 나타내었고 추출시간에 영향을 받았다. In this study, various active functional components in Chinese Quince were extracted by solvent extraction method. A central composit design for optimization was applied to investigate the effects of independent variables such as solvent to sample ratio (X1), extraction temperature (X2), and extraction time (X3) on the soluble solid contents (Y1), total phenols (Y2), electron donating ability (Y3), browning color (Y4) and reducing sugar contents (Y5). It was found that extraction temperature and extraction time were the main effective factors in this extraction process. The maximum soluble solid contents of 35.77% was obtained at 26.38mL/g (X1), 72.82oC (X2) and 74.86 min (X3) in saddle point. Total phenols were rarely affected by solvent ratio and extraction time, but it was affected by extraction temperature. The maximum total phenols of 20.70% was obtained at 22.61mL/g (X1), 84.49oC (X2), 77.25 min (X3) in saddle point. The electron donating ability was affected by extraction time. The maximum electron donating ability of 94.12% was obtained at 10.65mL/g (X1), 67.78oC (X2), 96.75 min (X3) in saddle point. The maximum browning color of 0.32% was obtained at 23.77mL/g (X1), 87.27oC (X2), 96.68 min (X3) in saddle point. The maximum value of reducing sugar content of 10.55% was obtained at 26.83mL/g (X1), 82.167oC (X2), 81.94 min (X3). Reducing sugar content was affected by extraction time.

추돌시 Head Restraints 시스템의 구속 효과와 인체 상해에 관한 연구

이창민,Lee, Chang-Min 대한인간공학회 1998 大韓人間工學會誌 Vol.17 No.3

Focuses of this study are to investigate the usage status of head-restraint system(H/R) in usual driving and to simulate usage conditions of H/R at rear-end crashes. The usage of H/R was categorized into five classes according to the height and distance from occupant's head ; Large-$90^{\circ}$ H/R for enough height and short distance. Large-$70^{\circ}$ H/R for enough height and long distance. Small-$90^{\circ}$ H/R for low height and short distance. Small-$70^{\circ}$ H/R for low height and long distance. and No H/R. Then. these five conditions were tested to find out the degree of neck injuries by using a car-crash simulation package, DYNAMAN. Results from the investigation of H/R usage show that most of drivers(60%) have Small-$70^{\circ}$ H/R for low height and long distance. Results from the simulation performed at 15mph and 30mph show that: 1) at 15 mph, there is a possibility for neck injury in Small-$90^{\circ}$ H/R and Small-$70^{\circ}$ H/R. 2) at 30 mph. there is a high possibility of death in Small-$70^{\circ}$ H/R and Small-$90^{\circ}$ H/R.

PSS 상 버퍼층 종류에 따른 GaN 박막 성장 특성 비교

이창민,강병훈,김대식,변동진,Lee, Chang-Min,Kang, Byung Hoon,Kim, Dae-Sik,Byun, Dongjin 한국재료학회 2014 한국재료학회지 Vol.24 No.12

GaN is most commonly used to make LED elements. But, due to differences of the thermal expansion coefficient and lattice mismatch with sapphire, dislocations have occurred at about $109{\sim}1010/cm^2$. Generally, a low temperature GaN buffer layer is used between the GaN layer and the sapphire substrate in order to reduce the dislocation density and improve the characteristics of the thin film, and thus to increase the efficiency of the LED. Further, patterned sapphire substrate (PSS) are applied to improve the light extraction efficiency. In this experiment, using an AlN buffer layer on PSS in place of the GaN buffer layer that is used mainly to improve the properties of the GaN film, light extraction efficiency and overall properties of the thin film are improved at the same time. The AlN buffer layer was deposited by using a sputter and the AlN buffer layer thickness was determined to be 25 nm through XRD analysis after growing the GaN film at $1070^{\circ}C$ on the AlN buffer CPSS (C-plane Patterned Sapphire Substrate, AlN buffer 25 nm, 100 nm, 200 nm, 300 nm). The GaN film layer formed by applying a 2 step epitaxial lateral overgrowth (ELOG) process, and by changing temperatures ($1020{\sim}1070^{\circ}C$) and pressures (85~300 Torr). To confirm the surface morphology, we used SEM, AFM, and optical microscopy. To analyze the properties (dislocation density and crystallinity) of a thin film, we used HR-XRD and Cathodoluminescence.

상호안전성을 고려한 차대차 정면 충돌 안전성 선행 연구

이창민,신장호,김현우,박건호,박영준,Lee, Chang min,Shin, Jang ho,Kim, Hyun woo,Park, Kun ho,Park, Young joon 한국자동차안전학회 2017 자동차안전학회지 Vol.9 No.1

In recent years, NCAP regulations of many countries have induced automaker to improve the vehicle crashworthiness. But, the current NCAP regulations don't cover all types of traffic accidents. And rapid-increasing market share of compact cars and SUVs has brought for both consumer and automaker to pay more attention on crash compatibility. So, many countries have tried to develop the new crash test mode and update the present crash test mode. Especially, Euro NCAP has been developing a new impact protocol of the car-to-car frontal offset impact including the crash compatibility assessment. There are plans to introduce this new protocol in 2020, and it will be replaced the current Euro NCAP frontal offset impact. The test dummy in the front seats of this new test mode will be changed from 50% Hybrid-III male to 50% THOR male. This paper will address the vehicle responses, the occupant responses and the vehicle compatibility performance from a full vehicle crash test using the new car-to-car frontal offset test protocol of Euro NCAP.

식도에 발생한 거대 해면혈관종 수술치험 - 1례 보고 -

이창민,박성달,조성래,허방,Lee, Chang-Min,Park, Sung-Dal,Cho, Sung-Rae,Huh, Bang 대한흉부심장혈관외과학회 1998 Journal of Chest Surgery (J Chest Surg) Vol.31 No.3

식도에 발생하는 혈관종은 식도에 드물게 발생하는 양성종양의 2% 내지 3% 정도 차지할 정도로 매우 희귀하여 세계적으로 보고된 증례수가 많지 않다. 저자들은 식도에 발생한 매우 희귀한 해면혈관종 1례를 수술치험하였기에 문헌고찰과 더불어 보고하고자 한다. 환자는 40세 남 米\ulcorner경미한 연하장애를 주소로 내원하여 식도조영술, 식도 내시경검사, 조영제를 이용한 흉부 전산화 단층촬영등을 시행하여 하부 식도의 점막하층에서 발생하여 근육층 밖으로 돌출되어 나온 식도 종양이 추정되어 수술을 시행하였다. 수술소견상 하부 식도 및 식도-위 문합부에 걸쳐 과혈관성의 7x7x3.5cm 크기의 거대한 종괴가 식도점막하층과 식도근육층 그리고 주위조직으로의 침범이 심하게 되어 있어 종양을 포함한 식도절제술 및 식도-위 문합술을 시행하여 병리 조직학적으로 해면 혈관종으로 확진되었으며 환자는 특별한 문제없이 술후 제14일째 건강한 상태로 퇴원하였다. Esophageal hemangioma is an extremely rare benign tumor that causes dysphagia and massive upper gastrointestinal bleeding. Although certain abnormalities seen on a barium swallow esophagography or at endoscopy may suggest an esophageal hemangioma, a contrast CT and radionuclide angiography using a blood-pool radiopharmaceutical can characterize the intense vascularity of the tumor. We experienced the ase of a 7$\times$7$\times$3.5 cm in size giant cavernous hemangioma of the lower 1/3 of esophagus in a 40 year old man. A mural cavernous hemangioma was diagnosed with a barium swallowed esophagogaphy, endoscopy, and a contrast CT. It was treated successfully by transthoracic esophagectomy including the tumor and esophagogastrostomy.

망막질환이 동반된 난치성 녹내장에서의 유리체절제술과 평면부를 통한 아메드장치삽입술

이창민,김은아,조영욱,Chang Min Lee,Eun Ah Kim,Young Wook Cho 대한안과학회 2011 대한안과학회지 Vol.52 No.1

Purpose: To evaluate the efficacy and long-term prognosis of pars plana vitrectomy and Ahmed valve implantation for intractable glaucoma comorbid with retinal disorders. Methods: A retrospective review of 34 eyes of 30 patients receiving pars plana vitrectomy and Ahmed valve implantation for intractable glaucoma comorbid with retinal disorders was performed. Preoperative and postoperative intraocular pressure (IOP) and visual acuity, the usage of IOP-lowering medications and postoperative complications, and surgical success rate were evaluated. Results: IOP and the number of IOP-lowering medications showed a significant decrease after pars plana vitrectomy and Ahmed valve implantation, as compared to before surgery (p < 0.001). The success rate was 88%, 88%, 84% and 85% postoperatively at 1 month, 6 months, 1 year and 3 years respectively. The mean follow up period was 24.21 ± 14.99 months. Complications related to surgery included hyphema in 2 eyes, recurrent corneal epithelial erosion and defect in 2 eyes, corneal ulcer in 2 eyes and vitreous hemorrhage in 4 eyes. Visual acuity improved in 14 eyes (41.1%), no changes in 13 eyes (38.2%) and decreased in 7 eyes (20.6%). Conclusions: Pars plana vitrectomy and Ahmed valve implantation for intractable glaucoma comorbid with retinal disorders show long-term efficacy in lowering IOP. J Korean Ophthalmol Soc 2011;52(1):46-52

구두 굽의 형태가 인체의 근골격계에 미치는 영향에 관한 연구

이창민,정은희,Lee, Chang-Min,Jeong, Eun-Hui 대한인간공학회 2004 大韓人間工學會誌 Vol.23 No.1

In terms of women engaged in clerical job. working time of the workers who mainly keep standing with their high-heeled shoes on has been increasing. According]y. they are exposed to many kinds of foot deformation caused by loads of lower back and lower extremities due to high-heeled shoes. The type of heels they usually wear are diverse though the hight is same. In this study. we investigated most women's favorite styles of shoes concerned with heights. types and contact areas of the heels. Hence. we designed three kinds of shoes for an experiment: their contact areas with ground are 1 cm2. 2-4 cm2 and over 9 cm2 according to the heel heights. respectively. To investigate the biomechanical effects. analysis of motion and EMG were applied to the experiments. In addition. foot pressure distribution was measured for more detailed analysis. Six healthy young women were participated in this experiments. The result showed the heel becoming higher and narrower increased not only fluctuation of CBM(Center of Body Mass). but also the load of low back muscle and lower extremities. Accordingly. there was significant difference among types of the heel in terms of the role supporting load of the body. though the height is same. Especially. the difference among the pressures on a foot was most significant. In conclusion. we verified biomechanical effects are related with the contact area of a heel with ground as well as the hight.

생체역학적 분석을 통한 보행 부하 감소용 인솔 개발

이창민,오연주,Lee, Chang-Min,Oh, Yeon-Ju 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.4

The mailman's shoes should be designed in due consideration of occupational features they spend most of times to walk. For that reason, the shoes required functions to reduce the foot fatigue and to protect body by dispersing the body weight to the whole foot. In this research, for the functional improvement of the insole, insoles are investigated and analyzed by biomechanics experimentation. Under the base of these experimental results, we develop insoles that can reduce the body load and muscular-skeletal disorder. The pressures are concentrated on the metatarsus and heel by the result of analyzing pressure distributions of the using shoes. Accordingly, we offer the prototype functional insole that is ranked from high pressure to low pressure on the base of a shock absorb function. This prototype functional insole is examined for statistical significance by pressure distribution areas. The experimental results show that pressure areas are dispersed to whole foot, for this reason, pressures of the metatarsus and heel are reduced. Results of this research can not only improve the function of insoles which is suitable for occupational features, but also be a base on constructing data bases for biomechanics gait insoles.

급성 특발성 양측성 아래눈꺼풀겉말림 1예

이창민,곽미선,박대진,Chang Min Lee,MD,Mi Sun Kwak,MD,PhD,Dae Jin Park,MD 대한안과학회 2010 대한안과학회지 Vol.51 No.1

Purpose: Ectropion is an eversion of the eyelid due to various causes, and it mainly develops in the lower lid. Usually it shows a slow progression, and it is classified as involutional, cicatricial, paralytic and congenital. Acute idiopathic bilateral lower lid ectropion is very rare; few cases have been reported worldwide, and none have been seen in Korea. Case summary: A 79-year-old male patient visited our department with a six-day history of epiphora and lower lid eversion in both eyes. On slit-lamp examination, lower lid ectropion was present in both eyes, and mild corneal punctate epithelial erosion was also observed. Two weeks after conservative treatment, the lower lid eversion disappeared and the lower lid returned to its original position. No changes were observed three months after treatment. We report a case of acute idiopathic bilateral lower lid ectropion with a literature review. J Korean Ophthalmol Soc 2010;51(1):126-130