• 한국대기환경학회지
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• 제30권6호
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• pp.619-630
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• 2014

Two butanol-based Condensation Particle Counters (CPC 3022, CPC 3025), three water-based CPCs (CPC3781, CPC3785${\times}$2), a Gardner Counter, a Fast Mobility Particle Sizer (FMPS), and an Aerosol Electrometer (AE) were deployed to measure the number concentrations from atomized aerosol under six different conditions. Comparisons of particle number concentrations measured by the CPCs, FMPS, and AE were conducted to evaluate the performance of the each CPCs using laboratory generated artificial particles such as NaCl, succinic acid ($C_4H_6O_4$), and particles generated by propane torch & heat gun in the chamber. Good correlation between the CPC3025 and FMPS was observed for the total particle number concentrations in the size range 15 nm to 90 nm. In addition, this paper suggests that photometric mode in water-based CPC3785 could not be used as quantitative of number concentrations for CPC3785.

• 한국자동차공학회논문집
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• 제19권1호
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• pp.109-116
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• 2011

To measure the traffic pollutants with high temporal and spatial resolution under real conditions a mobile emission laboratory (MEL) was designed and built in KIST with close-cooperation with KIMM and Yonsei university. The equipment of the mini-van provides gas phase measurements of CO, NOx, $CO_2$, THC (Total hydrocarbon) and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and a condensation particle counter (CPC). The inlet sampling port above the bumper enables the chasing of different type of vehicles. This paper introduces the construction and technical details of the MEL and presents data from the car chasing experiment of diesel and CNG city bus. The dilution ratio was increased rapidly according to the chasing distance. Most particles from the diesel city bus were counted under 300 nm and the peak concentration of the particles was located between 40-60 nm. However, the most particles from the CNG city bus were nano particle counted under 50 nm.

• 대한기계학회논문집B
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• 제36권7호
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• pp.737-744
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• 2012

차량에 의한 대기오염을 실제 주행 조건에서 시간과 공간에 구애받지 않고 실시간으로 측정하기 위하여 이동형 배출가스 측정장치(MEL)가 제작되었다. 미니밴 차량에 CO, NOx, $CO_2$와 같은 배출가스 측정 장비와 입자의 수농도 및 입경별 개수농도 분포 측정을 위한 FMPS, CPC가 탑재되었다. 차량 전단에 장착되는 흡입 샘플링 포트를 사용하여 여러 종류의 차량 추적 실험을 수행하였다. 본 연구에서는 MEL의 상세 사양 및 이를 이용하여 디젤 및 가솔린 연료를 사용하는 승용차량들을 추적 실험한 결과를 나타내었다. 디젤 차량에서 배출되는 입자의 수농도는 가솔린 차량에서 배출되는 입자의 수농도보다 높았으며 다량의 극미세입자를 포함하고 있었다. 하지만, 직접분사식 가솔린 차량은 DPF가 장착된 디젤 차량에 비하여 50 nm 이상의 입경 영역에서 입자의 농도가 높은 경향을 보였다.

• 대한불안의학회지
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• 제12권2호
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• pp.103-112
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• 2016

Objective : This study was conducted to examine the reliability and validity of the Measure of Constructs Underlying Perfectionism-Korean version (M-CUP-K). Methods : Two hundred and six normal subjects completed a battery of measures including M-CUP-K, Frost Multidimensional Perfectionism Scale-Korean version (FMPS-K), and Beck Depression Inventory (BDI). Psychometric properties of the M-CUP-K were analyzed. Results : The principal component analysis for construct validity resulted in 56 items composed of 6 factors (factor 1 : Dissatisfaction-Reactivity to Mistakes; factor 2 : Order-Details and Checking ; factor 3 : Satisfaction ; factor 4 : High standards ; factor 5 : Perceived Pressure from Others-Perfectionism toward Others ; factor 6 : Black and White Thinking about Tasks and Activities), compared to the original version. The M-CUP-K total and subscale scores were more strongly correlated with those of the other perfectionism-specific measure, FMPS-K, with a correlation of 0.822 (convergent validity) than with those of the nonspecific depression measure (discriminant validity). The Cronbach's ${\alpha}$ value for internal consistency of M-CUP-K was in an excellent range (r=0.872-0.935). The test-retest reliability for external validity suggested a good temporal stability with a total score correlation of 0.827. Conclusion : This study revealed that the M-CUP-K has good reliability and validity. Therefore, the M-CUP-K can be used as a promising measure of perfectionism in Korea.

• 대한기계학회논문집B
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• 제35권4호
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• pp.409-416
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• 2011

차량에 의한 대기오염을 실제 주행 조건에서 시간과 공간에 구애받지 않고 실시간으로 측정하기 위하여 이동형 배출가스 측정장치 (MEL)가 제작되었다. 미니밴 차량에 배출가스 측정을 위한 장비와 입자의 수 농도 및 입경분포 측정을 위한 FMPS, CPC가 탑재되었다. 차량 전단에 장착되는 흡입 샘플링 포트를 사용하여 여러 종류의 차량 추적 실험을 수행하였다. 본 연구에서는 MEL의 구축 과정 및 디젤, CNG, LPG 연료를 사용하는 버스를 추적 실험한 결과를 나타내었다. 배출가스의 희석비는 추적차량의 엔진 배기 NOx 및 MEL 차량에서 샘플링 되는 NOx의 비로 계산하였다. 디젤버스에서 배출되는 입자의 대부분은 300 nm 이하의 크기이며 입경분포의 피크값은 30~60 nm 사이에 위치하였다. 하지만, 가스연료인 CNG와 LPG를 사용하는 버스에서 배출되는 입자들은 극미세입자 영역인 50 nm 이하로 측정되었다.

• The Journal of Asian Finance, Economics and Business
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• 제8권1호
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• pp.285-294
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• 2021

The most basic forces of stock market are supply and demand, which increases or decreases on the basis of information. The crucial point is that investor's perception is depending on the availability of information at a particular time. But it is very difficult to understand what they take from a piece of information, and the decision varies from person to person; hence, it is important to understand the behavior of investors in the stock market. In this context, this study is focusing on behavioral investor-type diagnosis testing among financial market players (FMPs) in Oman. The study conducted a review of behavioral types among stock market investors, and attempted to assess the influence of age and gender factors on investor bias. It classifies investor type biases according to the gender and age of respondents. This study employs primary data with a structured questionnaire distributed to an equal number of male and female stock market investors in Muscat Securities Market. The study used sample t-test, one-way ANOVA, CATPCA and ALSCAL to identify the significant difference among age, gender and experience of the respondents. The present study found that all of the investors are influenced by different cognitive biases and, moreover, it depends on investor's gender.

• 한국자동차공학회논문집
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• 제20권6호
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• pp.24-32
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• 2012

A large fraction of urban $PM_{10}$ concentrations is due to non-exhaust traffic emissions including road dust, tire wear particles, and brake lining particles. Although potential health and environmental impacts associated with tire wear debris have been increased, few environmentally and biologically relevant studies of actual tire wear debris have been conducted. Tire wear particles (TWP) are released from the tire tread as a result of the interaction between the tire and the pavement. Roadway particles (RP), meanwhile, are particles on roads composed of a mixture of elements from tires, pavements, fuels, brakes, and environmental dust. The main objective of present study is to identify the contribution of tires to the generation of RP and to assess the potential environmental and health impacts of this contribution. First, a mobile measurement system was constructed and used to measure the roadway particles on asphalt road according to vehicle speed. The equipment of the mobile system provides $PM_{10}$ concentrations by Dusttrak DRX and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and an aerosol particle sizer (APS). When traveling on an asphalt road at constant speed, there is a clear tendency for PM10 concentration to increase slightly in accordance with an increase in the vehicle speed. It was also found that considerable brake wear particles and particles from tire/road interface were generated by rapid deceleration of the vehicle. The morphology and elements of the roadway particles were also analyzed using SEM-EDX technique.

• 한국자동차공학회논문집
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• 제20권3호
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• pp.88-97
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• 2012

To measure the traffic pollutants with high temporal and spatial resolution under real conditions, a mobile emission laboratory (MEL) was designed. The equipment of the mini-van provides gas phase measurements of CO, NOx, CO2 and THC (Total hydrocarbon), and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and a condensation particle counter (CPC). The inlet sampling port above the bumper enables the chasing of different type of vehicles. This paper introduces the technical details of the MEL and presents data from the experiment in which a MEL chases a city bus fuelled by diesel, DME and Bio-diesel. The dilution ratio was calculated by the ratio of ambient NOx and tail-pipe NOx. Most particles from the bus fuelled by diesel were counted under 300 nm and the peak concentration of the particles was located between 30 and 60 nm. However, most particles in the exhaust of the bus fuelled by DME were nano-particles (diameter: less than 50 nm). The bus fuelled by Bio-diesel shows less particle emissions compare to diesel bus due to the presence of the oxygen in the fuel.

• 한국대기환경학회지
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• 제28권2호
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• pp.131-141
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• 2012

A large fraction of urban $PM_{10}$ concentrations is due to non-exhaust traffic emissions including road dust, tire wear particles, and brake lining particles. Although potential health and environmental impacts associated with tire wear debris have increased, few environmentally and biologically relevant studies of actual tire wear debris have been conducted. Tire wear particles (TWP) are released from the tire tread as a result of the interaction between the tire and the pavement. Roadway particles (RP), meanwhile, are particles on roads composed of a mixture of elements from tires, pavements, fuels, brakes, and environmental dust. The main objective of present study is to identify the contribution of tires to the generation of RP and to assess the potential environmental and health impacts of this contribution. First, a mobile measurement system was constructed and used to measure the RP on asphalt roads according to vehicle speed. The equipment of the mobile system provides $PM_{10}$ concentrations by Dusttrak DRX and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and an aerosol particle sizer (APS). When traveling on an asphalt road at constant speed, there is a clear tendency for $PM_{10}$ concentration to increase slightly in accordance with an increase in the vehicle speed. It was also found that considerable brake wear particles and particles from tire/road interface were generated by rapid deceleration of the vehicle. As a result, the $PM_{10}$ concentration and particle number of ultra-fine particles were measured to be very high.

• 한국자동차공학회논문집
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• 제19권5호
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• pp.92-99
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• 2011

To measure the traffic pollutants with high temporal and spatial resolution under real conditions, a mobile emission laboratory (MEL) was designed. The equipment of the mini-van provides gas phase measurements of CO, NOx, $CO_2$, THC (Total hydrocarbon) and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and a condensation particle counter (CPC). The inlet sampling port above the bumper enables the chasing of different type of vehicles. This paper introduces the technical details of the MEL and presents data from the car chasing experiment of diesel bus equipped with aftertreatment system. The dilution ratio was calculated by the ratio of ambient NOx and tail-pipe NOx. Most particles from the diesel bus were counted under 300 nm and the peak concentration of the particles was located between 30 and 60 nm. The total PM number emission from diesel bus equipped with DPF was 10 orders of magnitude lower compared to those emitted from base diesel bus. And the total PM number emission from diesel bus equipped with SCR was comparable to the particle emission from base diesel bus.