The effects of secondary task on the control of vehicle under driving simulator: a study among 50s taxi drivers

Han Soo Kim,Jin Seung Choi,Dong Won Kang,Hong Won Yeon,Mi Hyun Choi,Doo Hwan Ji,Byung Chan Min,Soon Cheol Chung,Gye Rae Tack 대한인간공학회 2011 대한인간공학회 학술대회논문집 Vol.2011 No.5

Objective: The aim of this study is to quantitatively evaluate the effects of the secondary task during simulated driving using the variable indicating control of vehicle. Background: There are so many researches for simulated driving and performance. For instance, some researches show that the effects of cell phone conversations on simulated driving. Cell phone conversations impaired explicit recognition memory. Method: Participants included 50s taxi drivers; 15 males and 15 females. All subjects were instructed to keep a distance (30m) from the car ahead and a constant speed (80km/hr or 100km/hr). Sending text message (STM) and Searching navigation (SN) were selected as the secondary task. Experiment consisted of rest for 3min., driving alone for 1min. and driving with secondary task for 1 min.. We were analyzed anterior-posterior coefficient of variation (APCV) and medial-lateral coefficient of variation (MLCV). Results: APCV was increased by 175.4% in STM and 223.8% in SN at 80km/hr. MLCV was increased by 242.3% in STM and 323.4% in SN at 100km/hr. There was no significant difference between genders. Conclusion: Consequently, performing secondary task during driving impaired the control of vehicle.

미더덕의 생리활성이 향상된 아임계수 추출물의 제조

조민지(Min-Ji Jo),한지경(Ji-Kyoung Han),성수창(Su-Chang Sung),이승철(Seung-Cheol Lee) 한국식품영양과학회 2018 한국식품영양과학회지 Vol.47 No.11

미더덕의 이용 다변화를 위하여 아임계수 추출물을 제조하고 생리활성을 평가하였다. 미더덕은 동결건조 분말 상태로 10, 30, 60분 동안 다양한 온도(50, 100, 200, 300℃)에서 추출되었다. 아임계수 조건은 ACE 저해 활성, 항산화 활성, AChE 저해 활성과 같은 중요한 생리학적 특성을 상당히 증가시켰다. 200℃, 60분 추출물에서 가장 높은 ACE 저해활성을 나타냈으나 더 높은 온도 조건인 300℃에서는 급격히 감소하였다. DPPH 라디칼 소거능과 ABTS라디칼 소거능은 300℃, 30분 추출물에서 공통적으로 가장 높은 값을 보였고, AChE 저해 활성 또한 같은 경향을 나타냈다. 이러한 결과는 아임계수 추출이 미더덕의 생리활성을 증가시키는 유용한 가공방법이 될 수 있음을 시사한다. For diverse application of Styela clava (Korean name: miduduck) as a food material, subcritical water (SCW) extract was prepared and its physiological activity was evaluated. To accomplish this, S. clava powder (0.1 g) was placed in a stainless vessel containing 10 mL of distilled water, after which SCW extraction was carried out at 50, 100, 200, and 300℃ for 10, 30, and 60 min. SCW treatment significantly increased important physiological properties of the extract such as angiotensin converting enzyme (ACE) inhibitory activity, antioxidant activity, and acetylcholinesterase (AChE) inhibitory activity. The highest ACE inhibitory activity was found in samples subjected to SCW extraction at 200℃ for 60 min; however, the activity decreased at higher temperature (300℃). The SCW extract of S. clava prepared at 300℃ for 30 min showed the highest antioxidant activity [1,1-diphenyl-2-picrylhydrazyl and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities] and AChE inhibitory activity. These results indicate that SCW extraction might be a useful method for increasing the physiological activity of S. clava.

유화처리 바이오디젤이 도포된 콘크리트의 침투깊이 판정

백철 ( Baek Cheol ),김태우 ( Kim Tae-woo ),이재진 ( Lee Jae-jin ),이동윤 ( Lee Dong-yun ),한민철 ( Han Min-cheol ),한천구 ( Han Cheon-goo ) 한국건축시공학회 2017 한국건축시공학회 학술발표대회 논문집 Vol.17 No.2

This study is to provide a evaluation method for the penetration depth of emulsified refined bio diesel(ERBD)applied to a surface of the concrete by using water absorption capability of the concrete. The concrete applied with ERBD was immersed at water for 1 min., 5min., and 10 min. and then was checked the brightness with elapse of time. Test results indicated that there was clear difference between ERBD part and non ERBD part in concrete specimen after measuring the brightness until 120min.

대장내시경검사의 전처치로서 항콜린제 사용에 관한 연구 : 전향적, 이중맹검법으로

박경남,한동수,이민호,최호순,박준용,손주현,이오영,함준수,전용철,송승찬,기춘석,윤병철,이종희 대한소화기내시경학회 1997 Clinical Endoscopy Vol.17 No.3

Background: Use of antispasmodic medication prior to colonoscopy is controversial but someone believes antispasmodic may improve visualization of colonic mucosa and ease colonoscope insertion. So, we designed a study to assess the effect of premedication with the antispasmodic, hyoscine-N-butyl bromide(Buscopan') on the performance of colonoscopy. Methods: This study was prospective, double blinded, randomized, controlled study, One hundred three consecutive patients were randomized to receive intravenous buscopan lml(n=52) or placebo(n=51) combined with our standard initial medication(me- peridine 50 mg and midazolam 2 mg). Insertion of colonoscopy was timed, and 100 mm visual analogue scales (VAS) were used for asscssing difficulty of procedure, colonic motility, frequency of positional change, frequency of external compression, difficulty of assistance and degree of discomfort experienced by the patients. Results: There were no significant differences of intubation time between buscopan group(mean time, 7.23 min., range 2~15) and placebo group(7.07 min., range 3-25), (p=0.83) and withdrawal time between buscopan group (6.46 min., range 2-22) and placebo group(6.76 min., range 2 25), (p=0.69). Also, there was no significant differences in intubation time between males and females(buscopan; males 7.00 min., females 7.60 min., p=0.34, placebo; males 7.0~5 min., females 7.08 min., p 0.44). The VAS scores checked by endoscopist(p=0.29), assistant(p=0.32) and patient (p=0.15) were not significantly different in both groups. There were no significant differences in intubation time, VAS scores nf endoscopist, assistant, and patients. Conclusion: Premedication with intravenous bu.opan has no advantage on colonoscopy procedure. Use of antispasmodic medication prior to colonoscopy was not considered as recommendable agent.

단신 : 실리콘의 염소화반응에 의한 사염화규소 제조

박균영 ( Kyun Young Park ),이미선 ( Mi Sun Lee ),김민철 ( Min Cheol Kim ),이찬희 ( Chan Hee Lee ),박회경 ( Hoey Kyung Park ),강태원 ( Tae Won Kang ),정해성 ( Hae Seong Jeong ),한경아 ( Kyoung Ah Han ),허원회 ( Weon Hoe Huh ),유지 한국화학공학회 2013 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.51 No.3

직경 25 mm의 파이렉스 튜브 내에서 실리콘의 유동층 염소화 반응이 수행되었다. 반응기에 공급되는 질소 유량0.8~1.0 L/min, 염소 유량 0.2 L/min, 반응온도 450℃, SiCl4 응축기의 냉매온도는 -5℃로 설정하였다. 반응기에 도입되는 가스 내 염소의 몰분율이 증가하면 SiCl4의 수율이 증가하였다. 반응가스 중 염소의 몰분율 0.2의 조건에서 SiCl4의 수율은 28% 이었다. 염소의 몰분율 증가는 반응열 상승에 의해 반응온도 상승을 가져옴으로써 안전을 고려하여 염소의 몰분율을 0.2 이상으로 올리지 못했다. 실리콘의 유동층 염소화 반응에 의한 사염화실리콘의 제조 가능성이 입증되 었으며, 향후 보다 가혹한 조건에서의 실용화 연구를 위한 기초로 활용될 수 있을 것으로 기대된다. The chlorination of a metallurgical-grade silicon was carried out in a fluidized bed reactor, 25 mm in diameter. The flow rate of the chlorine admitted into the reactor was 0.2 L/min and that of the carrier nitrogen was 0.8~1.0 L/ min. The reactor temperature was maintained at 450℃ and the temperature of the coolant at the SiCl4 condenser was at -5℃. The SiCl4 yield increased with increasing the mole fraction of chlorine in the feed gas, exhibiting 28% at the mole fraction of 0.2. Further increase of the chlorine mole fraction was not attempted in a worry that the reactor might be failed due to the high exothermicity of the reaction. The production of SiCl4 from silicon by fluidized bed chlorination was demonstrated on a laboratory scale, which is a stepping stone for future studies under more severe conditions toward industrial application.

우리나라 한중콘크리트 적용기간의 변화에 관한 고찰

한민철,김경민,신동안,윤기원,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

In this paper. variations of the period of cold weather concrete in Korea are discussed based on the climate data of Korean Meteorological Adminstration(KMA). Determination of the period of cold weather concrete with the region is done by following Korean Concrete Institute(KCD, American Concrete Institute(ACD and AIJ(Architectural Institute of Japan(AIJ) specification. Present study is compared with previous study done by the authors. Period of cold weather concrete is found to increase with high altitude and in-land and mountain area. Period of cold weather concrete by present study is shorted compared with that of previous study by about 3~6 days regardless of applied specification. Especially. the period of cold weather concrete at southern region near sea is reduced remarkably compared with that of previous study. This is due the rise of mean air temperature by global warming. In the scope of present study, period of cold weather concrete is provided with table and map diagram.

초지연 콘크리트의 응결시간 예측을 통한 강도증진 해석

한민철 청주대학교 산업과학연구소 2006 産業科學硏究 Vol.24 No.1

In this paper, the applicability of maturity approach to the estimation of compressive strength of concrete using super retarding agent(SRA) is described based on apparent activation energy at the final set time, which is derived from Arrhenius function. Arrhenius function to obtain apparent activation energy(E_(a)) and Freisleben-Hansen maturity function to achieve the equivalent age were applied in this paper. To obtain apparent activation energy during setting time, modification of Arrhenius function prescribed by ASTM C 1074 was done by substituting ln(kT) for ln(1/t) for Y axis. Apparent activation energy derived from Arrhenius function ranged from 30∼35 KJ/mol for plain concrete and it also ranged from 20∼40 KJ/mol for concrete with SRA. Good agreement between predicted strength and measured strength was obtained based on the estimation of compressive strength applying equivalent age computed from apparent activation energy at final set time. It was found that apparent activation energy derived from setting time could be used to predict the setting time as well as strength estimation of concrete containing SRA successfully.

양측 양성성대질환에 대한 연구

안철민,정덕희,한규철,박상준,이건영 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.7

슈미트햄머의 반발도 및 초음파속도에 미치는 결합재의 영향

한민철,이백수,윤기원,최영화,한천구 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

This paper reports the influence of kinds of cement and replacing ratio of fly ash(FA) and blast furnace slag powder(BS) on estimation of compressive strength by non-destructive test. According to the results, the compressive strength, the rebound value of schmidt hammer and ultrasonic pulse velocity show the higher value in order of AMC, UHC and OPC. In concrete replaced with mineral admixture, they are lower at early age, but higher at the age of 91 days compared with plain concrete. As the influence of the kinds of cement, estimated compressive strength by Schmidt hammer is almost same in the case of UHC, but much lower at the same rebound value in the case of AMC, in comparison with OPC. But the influence of mineral admixture is very insignificant. Compressive strength estimated by ultrasonic pulse velocity method shows the higher value by 10MPa, 12.5MPa in the case of UHC and AMC respectively compared with OPC, and the influence of mineral admixture on ultrasonic pulse velocity is insignificant.

AHP 기법에 의한 고강도 콘크리트의 화재시 폭렬방지 성능의 중요도 결정

한민철,백대현 청주대학교 산업과학연구소 2009 産業科學硏究 Vol.26 No.2

Currently, with the drastic increase of high rise and huge scale building construction, the use of high strength concrete has been increasing. High strength concrete has dense pore structure, which is susceptible to be damaged due to fire attack. There are various fire resistant methods of high strength concrete in the fields. However, it's hard to adapt a proper method reflecting various performance include economical profits, constructability and spalling resistance. In this paper, to provide the priority for selecting fire endurance method in high strength concrete execution, Analytical hierarchy Process (AHP) technique is applied based on expert questionnaire. Fire endurance performance efficiency and ordinary performance efficiency was selected for level 1. Fire endurance performance efficiency had larger weight than ordinary one. Adding organic fiber has superiority to board attachment methods.