• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.2
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• pp.56-63
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• 2012

Environment has become a main issue nowadays. People began to show big interest in "futuristic means of transportation", which is an efficient method in $CO_2$ emissions reduction and decreasing use of oil. Due to the noise and emissions of two-wheel vehicle of internal combustion engine, electric two-wheeled vehicles have been supplied in downtown. The electric two-wheeled vehicles use battery as power source. The performance of lithium-ion battery changes as the ambient temperature changes. In this paper, analysis of performance variance of electric two-wheeled vehicles influenced by the temperature using the chassis dynamometer and the environmental chamber was carried out.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.4 s.27
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• pp.233-239
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• 2006

This paper aims to evaluate the operation efficiency of Korean RCC(Rescue Co-ordination Center)/RSC(Rescue Sub-Center) using DEA(Data Envelopment Analysis). for this evaluation, this paper use the quantitative data for DEA analysis with two inputs and four outputs and a qualitative data analysis with the use of expert assessment. The tool for integrating heterogeneous data is fuzzy logic model to decision support system. In this paper, therefore, RCC/RSC evaluates the priority for operation efficiency. The result are found as order as Inchon, Mokpo, Jeju, Donghae, Busan, Pohang, Yosu, Sokcho, Tongyeong, Ulsan, Taean, Gunsan RSC.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.67-72
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• 2005

This paper aims to evaluates the operation efficiency with two inputs and four outputs with the use of DEA(Data Envelopment Analysis), a qualitative data analysis with the use of expert assessment in Korean RCC(Rescue Co-ordination Center)/RSC(Rescue Sub-Center). The tool for integrating heterogeneous data is model that applies fuzzy logic to decision support system In this paper, therefor, RCC/RSC evaluates the priority for operation efficiency. The result are found as order as Inchon, Mokpo, Jeju, Donghae, Busan, Pohang, Yosu, Sokcho, Tongyeong, Ulsan, Taean, Gunsan RSC.

• Journal of Climate Change Research
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• v.9 no.1
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• pp.75-80
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• 2018

The problem of water shortages and water related disasters caused by climate change has increased the seriousness of water problems and the importance of water treatment technology capable of securing clean water is expanding. In this study, we analyzed not only the water pollutant generated by the filtration system technology of various water treatment technologies but also the indirect greenhouse gas emissions generation, and analyzed the influence on the environment. The subjects of study are Fabric Filter, Reverse Osmosis System and Pressurized Microfiltration Device which are widely used for water treatment and we analyzed the impact on the environment using the Life Cycle Assessment (LCA) method using the electricity amount necessary for use, the water purification efficiency, the throughput per ton and the cost. The amount of greenhouse gas generated when the Pressurized Microfiltration Device operates for 1 year is $2.15E+04kg\;CO_2-eq$., Fabric Filter is $3.29E+04kg\;CO_2-eq$., and Reverse Osmosis System is $1.68E+05kg\;CO_2-eq$. As a result of analyzing the amount of greenhouse gas generated at the time of purifying 1 ton of the Pressurized Microfiltration Device and the conventional filtration system, the Pressurized Microfiltration Device was $20.5g\;CO_2-eq$., Fabric Filter was $34.7g\;CO_2-eq$., and Reverse Osmosis System was $191.7g\;CO_2-eq$. The amount of greenhouse gas generated was calculated to be 41.0% less than that of the Fabric Filter by the Pressurized Microfiltration Device and 89.3% less than the Reverse Osmosis System. From the viewpoint of climate change, it is necessary to select a filtration system that takes climate change into account, not from the viewpoint of water quality removal efficiency and economic efficiency according to future water treatment applications, and it is necessary to select a water treatment filtration system more researches and improvements will be made for.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2207-2219
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• 2018

Activated carbon (AC) was synthesized from Phoenix dactylifera stones and then modified by $CoFe_2O_4$ magnetic nanocomposite for use as a Cr(VI) adsorbent. Both $AC/CoFe_2O_4$ composite and AC were fully characterized by FTIR, SEM, XRD, TEM, TGA, and VSM techniques. Based on the surface analyses, the addition of $CoFe_2O_4$ nanoparticles had a significant effect on the thermal stability and crystalline structure of AC. Factors affecting chromium removal efficiency like pH, dosage, contact time, temperature, and initial Cr(VI) concentration were investigated. The best pH was found 2 and 3 for Cr adsorption by AC and $AC/CoFe_2O_4$ composite, respectively. The presence of ion sulfate had a greater effect on the chromium sorption efficiency than nitrate and chlorine ions. The results illustrated that both adsorbents can be used up to seven times to adsorb chromium. The adsorption process was examined by three isothermal models, and Freundlich was chosen as the best one. The experimental data were well fitted by pseudo-second-order kinetic model. The half-life ($t_{1/2}$) of hexavalent chromium using AC and $AC/CoFe_2O_4$ magnetic composite was obtained as 5.18 min and 1.52 min, respectively. Cr(VI) adsorption by AC and $AC/CoFe_2O_4$ magnetic composite was spontaneous and exothermic. In general, our study showed that the composition of $CoFe_2O_4$ magnetic nanoparticles with AC can increase the adsorption capacity of AC from 36 mg/L to 70 mg/L.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.163-166
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• 2003

Laser-Induced Thermal Imaging (LITI) is a laser addressed patterning process and has unique advantages, such as high-resolution patterning with over-all position accuracy of the imaged stripes within 2.5 micrometer and scalability to large-size mother glass. This accuracy is accomplished using real-time error correction and a high -resolution stage control system that includes laser interferometers. Here the new concept of mixed hybrid system which complement the advantages of small molecular and polymeric materials for use as an OLED; our system can realize the easy processing of polymers and high luminance efficiency of recently developed small molecules. LITI process enables to pattern the stripes with excellent thickness uniformity and multi-stacking of various functional layers without using any type of fine metal shadow mask. In this study, we report a full-color hybrid OLED using the multi-layered structure of small molecular/polymeric species.

• Corrosion Science and Technology
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• v.11 no.2
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• pp.37-42
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• 2012

Recent issues in the automotive industries are, improvement of fuel efficiency according to the worldwide $CO_2$ regulation, passenger safety through enhanced crashworthiness, superior design and cost reduction due to price fluctuation of raw material. To meet these demands, steelmaking companies are developing advanced high strength steel and new process technologies such as hydroforming, TWB(Tailor Welded Blank), hot stamping and so on. In addition, eco-friendly and high corrosion resistant coating technologies are getting more attention to comply with the environmental regulations. In this paper, reviews and prospects of recent coating technologies for automotive use are presented.

• Economic and Environmental Geology
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• v.49 no.6
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• pp.469-477
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• 2016

To evaluate the $CO_2$ storage capacity for the reservoir rock, the laboratory scale technique to measure the amount of $scCO_2$, replacing pore water of the reservior rock after the $CO_2$ injection was developed in this study. Laboratory experiments were performed to measure the $scCO_2$ displacement efficiency of the conglomerate and the sandstone in Janggi basin, which are classified as available $CO_2$ storage rocks in Korea. The high pressurized stainless steel cell containing two different walls was designed and undisturbed rock cores acquired from the deep drilling site around Janggi basin were used for the experiments. From the lab experiments, the average $scCO_2$ displacement efficiency of the conglomerate and the sandstone in Janggi basin was measured at 31.2% and 14.4%, respectively, which can be used to evaluate the feasibility of the Janggi basin as a $scCO_2$ storage site in Korea. Assuming that the effective radius of the $CO_2$ storage formations is 250 m and the average thickness of the conglomerate and the sandstone formation under 800 m in depth is 50 m each (from data of the drilling profile and the geophysical survey), the $scCO_2$ storage capacity of the reservoir rocks around the probable $scCO_2$ injection site in Janggi basin was calculated at 264,592 metric ton, demonstrating that the conglomerate and the sandstone formations in Janggi basin have a great potential for use as a pilot scale test site for the $CO_2$ storage in Korea.

• New & Renewable Energy
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• v.5 no.4
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• pp.46-51
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• 2009

The purpose of this study is to investigate selective adsorption of $CO_2$ from LFG (Landfill gas) by using commercialized NaX-type zeolite adsorbent under the ambient temperature and pressure. The experiment of $CO_2$ adsorption was carried out by using simulated LFG. The $CO_2$ adsorption capacity and separation efficiency of NaX-type adsorbent were investigated by analyzing gas flow rate and gas composition at inlet and outlet of the adsorption reactor. The adsorbed $CO_2$ were desorbed under decompression condition which 0.5 Torr or by air purge. Through the result to use simulated LFG, when the method of VSA was used, 73.2~75.3 mg of $CO_2$ was adsorbed per 1 g commercial adsorbent, when the method of air purge was used, 78.4~83.2 mg of $CO_2$ was adsorbed per 1 g of commercial adsorbent.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.303-309
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• 2006

The study examined the effects of $CO_2$ enrichment on growth of soybean (Glycine max). Two soybean varieties were used, Taekwang and Cheongja. The plants were grown in growth chambers with a 12-h photoperiod and a day/night temperature of $28/21^{\circ}C$ at the seedling stage and $30/23^{\circ}C$ from the flowering stage. The plants were exposed to the two elevated $CO_2$ levels of 500 and 700 ppm and the ambient level of 350 ppm. Results of the experiment showed that at the second-node trifoliate stage of the two varieties, the elevated $CO_2$ increased plant height, leaf area and dry weight. The elevated $CO_2$ also raised the photosynthetic rate of soybean as compared to the ambient level. From the beginning bloom stage to the full maturity stage of the two varieties, the elevated $CO_2$ increased plant height, leaf area, seed weight and photosynthetic rate. The stomatal conductance and transpiration rate decreased on long days relative to short days of treatment. Through the entire stages, the elevated $CO_2$ increased the water use efficiency of soybean plants because stomatal conductance and transpiration rate decreased at the elevated $CO_2$ levels relative to the ambient level.