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

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제22권1호
• /
• pp.13-17
• /
• 2017

Over 30% of domestic soil contamination has occurred via petroleum products and complex oil. Moreover, contamination by complex oil is more intense than it is by a single petroleum product species. In this study, we analyzed sectional TPH (total petroleum hydrocarbon) pattern and sectional ratio of current domestically distributed petroleum products, such as kerosene, diesel, bunker C, and lubricant and complex oils, to determine pollution characteristics of the soil. In the TPH pattern, kerosene, which is a light distillate, had an early retention time, and lubricant oil, which is a heavy distillate, had a late retention time in the gas chromatogram. In addition, we obtained a complexly contaminated soil via diesel and lubricant oil from the Navy and inspected it for its ratio of complex oil species. The inspection results showed that this soil was contaminated with 85% diesel and 15% lubricant oil. The method developed in this study could be used to determine complex petroleum sources and ratios at sites with accidentally contaminated soil.

• 한국추진공학회지
• /
• 제5권2호
• /
• pp.32-37
• /
• 2001

본 논문에서는 현재 시판되고 있는 주요 정유회사의 MTBE 가솔린을 이용하여 차량 배출 배기가스를 측정하였다. 배출 가스량은 차량 동력계상에 실제차량을 탑재하여 시험차량의 배기관에서 배출된 배출가스를 포집 하였으며, 우리나라의 공인배출가스 시험방법인 CVS-75 모드를 추적 주행하여 측정 하였다. CVS-75 모드는 cold start cycle, hot stabilized cycle 및 hot start cycle로 구성되며, 본 실험에서 분석한 배출가스는 일산화탄소, 질소산화물 및 탄화수소 등이다. 실험결과 배출 가스의 양에 있어서 근소한 차이만 보이고 있음을 알 수 있었다.

• 대한기계학회논문집A
• /
• 제31권12호
• /
• pp.1157-1164
• /
• 2007

Ceramic honeycomb structures have performed successfully as catalyst supports for meeting hydrocarbon, carbon monoxide and nitrous emissions standards for gasoline-powered vehicles. Three-way catalyst converter has to withstand high temperature and thermal stress due to pressure fluctuations and vibrations. Thermal stress constitutes a major portion of the total stress which the ceramic catalyst support experiences in service. In this study, temperature distribution was measured at ceramic catalyst supports. Thermal durability was evaluated by power series dynamic fatigue damage model. Radial temperature gradient was higher than axial temperature gradient. Thermal stresses depended on direction of elastic modulus. Axial stresses are higher than tangential stresses. Tangential and axial stresses remained below thermal fatigue threshold in all engine operation ranges.

• 한국염색가공학회지
• /
• 제6권4호
• /
• pp.17-26
• /
• 1994

Poly(ethylene terephthalate)(PET) filaments were treated in binary mixtures of organic solvents such as benzyl alcohol/perchloroethylene(BA/PER), benzyl alcohol/trichloroethylene(BA/TRI), benzyl alcohol/ethylene chloride(BA/EC), methanol/perchloroethylene (ME/PER), and methanol/trichloroethylene(ME/TRI). From the equilibrium swelling of PET, total and partial isotherms of PET for sorption of solvent mixtures and isotherms for distribution of the components between the phases were taken. Also the shrinkage and the crystallinity of PET treated with binary mixtures were investigated. The results obtained were summerized as follows: 1. All isotherms for distribution of the components between the phase deviated from the diagonal in system of PET-binary mixtures. Especially in the binary mixtures of ME/PER or ME/TRI, selectivo sorption of chlorinated hydrocarbon PER and TRI by PET occured. 2. The shrinkage of PET treated in binary mixrures was increased to compare with single solvent-treated, but the composition of binary mixtures corresponding to maximum values of shrinkage was not always agreed with the composition of binary mixtures corresponding to maximum values of shrinkage was not always agreed with the composition of binary mixtures exhibiting of the maximum swelling of PET. 3. The crystallinity of PET treated in binary mixtures generally increased than that of single solvent-treated.

• 환경위생공학
• /
• 제15권3호
• /
• pp.75-87
• /
• 2000

This study was conducted to investigate the composition, detection rate, and exposure concentration of the airborne organic solvents from the working environmental measurements of total 4181 different type of workplace in 3280 workshops in which organic solvents are used. The results are as follows : 1. For all workplaces except washing, the detection rate of toluene and benzene were 80% and 20%, respectively. 2. The number of detection of aromatic hydrocarbon and ketone were ranged 1.41-2.39 and 0.62-0.90 per a sample in all workplaces except that showed 1.01 in washing. 3. The mean of detection frequency was $3.3{\pm}2.5$ in all workplaces and there was no significant difference among that of each workplaces. 4. The airborne concentrations of methyl methacrylate, ethyl alcohol, methyl alcohol, and ethyl ether were $43.5{\pm}47.0{\;}ppm,{\;}22.5{\pm}51.0{\;},{\;}19.8{\pm}57.6{\;}ppm,{\;}19.8{\pm}40.14{\;}ppm, respectively. And those of cellosolve, methyl cellosolve acetate, and N,N-dimethyl formamide were $4.1{\pm}4.5$ ppm, $4.0{\pm}18.5{\;}ppm$, and $5.6{\pm}7.7{\;}ppm$, respectively and exceeded the occupational exposure limits enforced by Ministry of Labor in Korea. As the above results, it is suggested that the components of organic solvents should be indentified to efficient management, of working environment and conducted the engineering control for the workplaces using the hazardous materials.

• Toxicological Research
• /
• 제31권3호
• /
• pp.265-271
• /
• 2015

This study was carried out to investigate contents of 8 polycyclic aromatic hydrocarbons (PAHs) from frequently consumed seafood and dairy products and to evaluate their chemical analysis methods. Samples were collected from markets of 9 cities in Korea chosen as the population reference and evaluated. The methodology involved saponification, extraction with n-hexane, clean-up on Sep-Pak silica cartridges and gas chromatograph-mass spectrometry analysis. Validation proceeded on 2 matrices. Recoveries for 8 PAHs ranged from 86.87 to 103.57%. The limit of detection (LOD) 8 PAHs was $0.04{\sim}0.20{\mu}g/kg$, and limit of quantification (LOQ) of 8 PAHs was $0.12{\sim}0.60{\mu}g/kg$. The mean concentration of benzo[a]pyrene (BaP) was $0.34{\mu}g/kg$ from seafood and $0.34{\mu}g/kg$ from dairy products. The total PAHs concentration was $1.06{\mu}g/kg$ in seafood and $1.52{\mu}g/kg$ in dairy products.

• 한국대기환경학회지
• /
• 제30권3호
• /
• pp.211-222
• /
• 2014

Pork belly meat is one of the most preferred food items for many Korean people. The odorants released from cooking of pork belly meat were measured by three kinds of cooking methods (Charcoal-grill (C), Electric Pan (E), and Gas burner-pan (G)). A total of 16 target compounds including carbonyl compounds, volatile organic compounds, and poly aromatic hydrocarbon were selected and analyzed for comparative purposes. Their emission concentrations were quantified using HPLC-UV, GC-MS, GC-TOF-MS, etc. The gas samples collected by Charcoal-grill cooking showed generally enhanced concentrations of most target compounds among all three kinds of cooking methods. In Charcoal-grill, concentration of benzene, formaldehyde and pyrene went up to 543, 516, and 402 ppb, respectively. It the results are compared in terms of the sum of odor intensity, the highest value (4.25) was also seen from Charcoal-grill. The results of this study confirm that the significantly reduced emission of harmful pollutants can be attained, it pork belly meat is cooked by the Gas or electric pan instead of Charcoal-grill.

• Geomechanics and Engineering
• /
• 제8권3호
• /
• pp.461-476
• /
• 2015

Rankine's theory of earth pressure cannot be directly employed to c-${\phi}$ soils backfill with a sloping ground subjected to complex loadings. In this paper, an analytical solution for active earth pressures on retaining structures of cohesive backfill with an inclined surface subjected to surcharge, pore water pressure and seismic loadings, are derived on the basis of the lower-bound theorem of limit analysis combined with Rankine's earth pressure theory and the Mohr-Coulomb yield criterion. The generalized active earth pressure coefficients (dimensionless total active thrusts) are presented for use in comprehensive design charts which eliminate the need for tedious and cumbersome graphical diagram process. Charts are developed for rigid earth retaining structures under complex environmental loadings such as the surcharge, pore water pressure and seismic inertia force. An example is presented to illustrate the practical application for the proposed coefficient charts.

• Structural Engineering and Mechanics
• /
• 제68권2호
• /
• pp.237-245
• /
• 2018

This study proposes an empirical formulation to predict the maximum deformation of offshore blast wall structure that is subjected to impact loading caused by hydrocarbon explosion. The blast wall model is assumed to be supported by a simply-supported boundary condition and corrugated panel is modelled. In total, 1,620 cases of LS-DYNA simulations were conducted to predict the maximum deformation of blast wall, and they were then used as input data for the development of the empirical formulation by regression analysis. Stainless steel was employed as materials and the strain rate effect was also taken into account. For the development of empirical formulation, a wide range of parametric studies were conducted by considering the main design parameters for corrugated panel, such as geometric properties (corrugation angle, breadth, height and thickness) and load profiles (peak pressure and time). In the case of the blast profile, idealised triangular shape is assumed. It is expected that the obtained empirical formulation will be useful for structural designers to predict maximum deformation of blast wall installed in offshore topside structures in the early design stage.