• Journal of Korean Society for Atmospheric Environment
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• v.28 no.2
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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.

• Journal of the Korea Convergence Society
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• v.7 no.5
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• pp.161-167
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• 2016

Distribution channels are changing its industry paradigm from quantitative increase to qualitative improvement. In addition, it incorporates new characteristics and consumption tread of customers and the core value of service is developing focused around on online to offline (O2O) business model of omnichannel. In this respect, companies are integrating various distribution channels and in order to provide high content business service to customers, their interest in finding a new business strategy is increasing. Currently, most of the service being provided to customers are formed based on distribution structure centered around big companies and financial industry and the problems faced by small to medium and micro enterprises, which are expansion and improvement of channels, discovery of new distribution channels and finding O2O marketing strategy, can be said as very important task. Accordingly, this research purports to create added values which can serve as the driving force of growth of "creative economy" by improving distribution channels in which anyone who incorporates needs of smart consumers can enter into the smart commerce market and to further form sustainable win-win market that is strategic through business platforms for small to medium and micro enterprises therefrom.

• Journal of the Korean Geographical Society
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• v.46 no.4
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• pp.425-441
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• 2011

Ridge traversing trail in Mount Jiri National Park is classified as flat, gully-like, unilateral, and asymmetric bilateral, paths based on a location and gradient of paths. These types are interchangeable due to a drainage condition of trail surfaces. Using a rapid survey, the trail is 135.9 cm wide, 23.6 cm deep and $5.1^{\circ}$ in a gradient, respectively. All treads have been compacted due to human trampling. The path width is affected by a slope aspect and a distribution of Sasa borealis. An asymmetric path is wider than a symmetric path. A soil erosion rate is equivalent to $68.9cm^2/year$ for the period from 1960 to 2009, suggesting that the trail has been widened 2.7 cm/year and the tread lowered 0.4 cm/year. Trampling and needle ice action combined with rainwash induced by a pipeflow are dominant erosion processes contributing to the trail expansion.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.547-555
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• 2016

The wheel wear of a railway vehicle is mainly generated when maneuvering on a curved track. The change in the wheel profile affects the dynamic stability of the vehicle. In this analysis, the wheel wear volume was calculated while changing the velocity and radius of the curve to analyze the wear characteristics of a wheel at a curved section. The wear index was calculated from a vehicle dynamic analysis based on a multibody dynamics analysis and wear volume from a wear model by British Rail Research. The wear volume at a radius of 300 m is dominant compared with other radii. The wear volume was calculated by assigning different coefficients of friction to the tread and flange of the wheel to investigate the effect of lubrication on the wear characteristics. The effect of the improvement by lubrication is calculated by varying the radius of the track, and is assessed on an actual urban railway section.

• Elastomers and Composites
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• v.50 no.2
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• pp.110-118
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• 2015

In this study, diethylaminoethyl methacrylate-styrene-butadiene terpolymer (DEAEMA-SBR), in which diethylaminoethyl methacrylate (DEAEMA) was introduced to the SBR molecule as a third monomer, was synthesized by cold emulsion polymerization. It is expected that amine group introduced to a rubber molecule would improve dispersion of silica by the formation of hydrogen bond (or ionic coupling) between the amine group and silanol groups of silica surface. The chemical structure of DEAEMA-SBR was analyzed using proton nuclear magnetic resonance spectroscopy (H-NMR), Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). Then, various properties of DEAEMA-SBR/silica composite such as crosslink density, bound rubber content, abrasion resistance, and mechanical properties were evaluated. As a result, bound rubber content and crosslink density of DEAEMA-SBR/silica compound were higher than those of the SBR 1721 composite. Abrasion resistance and moduli at 300% elongation of the DEAEMA-SBR/silica composite were better than those of SBR 1721 composite due to the high bound rubber content and crosslink density. These results are attributed to high affinity between DEAEMA-SBR and silica. The proposed study suggests that DEAEMA-SBR can help to improve mechanical properties and abrasion resistance of the tire tread part.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.1
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• pp.23-28
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• 2006

The purpose of this paper was to clarify the actual conditions of the 'Dietary externalization' mainly by using the economic and nutrition-related data, accompanied by the economic development in Korea and Japan. 'Modernization of food style' and other modernization have taken place, among which 'Dietary externalization' in particular has recently drawn interest. At the time this paper clarified with econometric analysis whether there are differences between the two countries in term of the modernization of food style and dietary externalization trend. The trends of Dietary externalization of both Korea and Japan were studied using Principal Component Analysis method. The food subgroup were investigated based on the annual report on the household income and expenditure survey of Korea and the annual report on the family income and expenditure survey of Japan. The statistical data from both country were analyzed by SAS program. The results are as follows; 1. In Korea, the ratio of carbohydrates in the total calorie intake is quite high and animal protein is rather low compared to those in Japan. 2. Traditional food such as grains and vegetables are consumed much more in Korea than in Japan. 3. The Principal Component 1, 2 were extracted in both countries during the whole analysis period, which suggested the 'Dietary externalization' 4. Principal Component 1 has a positive factor loaded in all food items including meals outside the home and process food. In other words, it is apparent that the 'Dietary externalization' tread in Korea has a simple pattern suggesting that all externalization related items are on the rise. 5. Principal component 1, 2 which indicated the dietary externalization, were detected in Japan.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.3
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• pp.145-153
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• 2009

The purpose of this research is to propose a system to detect a strip defect on a iron plate using an image processing, one way of finding defects on an iron plate. An existing way of image processing is using a light source which release a light energy in a certain frequency and a light absorbing display which responds to the light source. This research attempts to detect defects by using a image processing and multi-Tread which handles an illumination, without depending on characteristics of light frequency. One of the advantages of this method is that it makes up for the weakness of the existing method which was too difficult for users to notice a defect. Also this method makes it possible to realize a real-time monitoring on a plate of iron. The other advantage of this method is that it reduces the price of hardwares on demand to match the frequency of light emitting display and light absorbing display because this method only needs a hardware which is easy to buy in any market.

• Journal of architectural history
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• v.20 no.1
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• pp.23-39
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• 2011

The Sungnyemun roofing tiles were twice disassembled for maintenance work, in 1963 and 1997, and modern tiles were applied in 1997. However, besides differing in visual appearance, the modern tiles had distinctly different physical properties. A study has been carried out on 22 different tiles, including original Sungnyemun tiles, modern tiles applied during maintenance, traditional tiles made by tile-makers, and others, to examine their physical properties, such as bending strength, frost resistance, absorption, whole-rock magnetic susceptibility, chromaticity, differential thermal analysis, and other characteristics. Since the method of making modern tiles involves compressing clay in a vacuum, modern tiles showed relatively greater bending strength and specific gravity, while Sungnyemun tiles and those made by tile-makers, in comparison, demonstrated less bending strength and specific gravity owing to their production method of 'treading,' in which clay is mixed by having someone tread upon it repeatedly. Over time, the absorption rate of the original tile used for Sungyemun gradually decreased from 21% to 14.7%; traditional tiles from tile-makers showed absorption rates of 17%, while the absorption rate of modern tiles was just 1%, which is significantly low. As for frost resistance, Sungnyemun tiles and traditional tiles from tile-makers showed cracking and exfoliation after being subjected to testing 4 or 5 times, while slight cracking was seen on the surface for modern tiles after 1ngy, or 3 times. In other words, no significant difference from influence by frost was found. According to the results of differential thermal analysis, the plastic temperature was shown to have been no less than 1, $on^{\circ}C$ for all types of tile, and cristobalite was measuredthrough XRD analysis from a Sungnyemun female tile applied during maintenance in 1963, which appeared to have been plasticized at between $1,200^{\circ}C{\sim}1,300^{\circ}C$. Based on these research results on the physical properties of tiles from the Sungnyemun roof, a fundamental production method for tiles to be applied in the restoration of Sungnyemun has been identified.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.262-264
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• 2016

In order to check the status of tire wear, a driver or auto mechanic generally checks tires with the naked eyes or with a coin. Those are easy for anyone but make it difficult to obtain precise information. But the result is a measure of mechanic wear out due to subjective judgment. Since we can not give correctly measure the stability of the tire. This may lead to an accident of the operator. Therefore, there is a need for a system checking tires precisely, accurately and easily, while making up for the aforementioned defect. This thesis has implemented a system with the aforementioned function. This system tire surface scanner data unit to determine the tread wear on the car and a storage unit for the data save, And a Web service unit allows the user to easily check the information.

• Korean Journal of Rural Living Science
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• v.9 no.1
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• pp.1-7
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• 1998

The purpose of this study is to investigate the effect of wearing sweat suit on sweating rate during jogging. 4 healthy female students served as subjects in the experimental chamber which was controlled 22$\pm$1$^{\circ}C$, 60$\pm$10%RH and no wind. The experimental clothes were Sweat Suit (SS) and General Suit (GE), SS was the product of R sports wear company which was consisted of long-sleeved jumper (100% polyester) and full length trousers (100% polyester) and GE were consisted of long sleeved shirt (100% cotton) and full length trousers (100% cotton). The subject wore same socks and shoes in both experimental clothes SS and GE. The subject reported at the experimental chamber at the same time on each experimental day. exchanged their clothes to the experimental clothes SS or GE, wore all sensors for the physiological measurements and had a rest in a sitting posture about 40 minutes. After rest, the subject carried out 30 min jogging on the tread mill with the speed 3.6miles/hour and during the jogging rectal temperature, skin temperatures (7 sites of the skin surface), heart rate, VO2, and evaporative weight loss were measured continuously and compared between two experimental clothes SS and GE. The major findings were as follows : The increase in rectal temperature during 30 min jogging was higher in experimental clothes SS than in GE and mean slim temperature kept higher in SS than in GE. VO2 and heart rate were a little bit higher in the later period of jogging in SS than in GE. The evaporative weight loss was greater in SS than in GE. These results indicate that the thermophysiological responses and sweating rate differs according to the wearing suit even though the subject performed same exercise.