• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.6
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• pp.367-380
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• 2014

Tsunami take away life, wash houses away and bring devastation to social infrastructures such as breakwaters, bridges and ports. The targeted coastal structure object in this study can be damaged mainly by the tsunami force together with foundation ground failure due to scouring and liquefaction. The increase of excess pore water pressure composed of oscillatory and residual components may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, the solitary wave was generated using 2D-NIT(Two-Dimensional Numerical Irregular wave Tank) model, and the dynamic wave pressure acting on the seabed and the estimated surface boundary of the vertical revetment. Simulation results were used as an input data in a finite element computer program(FLIP) for elasto-plastic seabed response. The time and spatial variations in excess pore water pressure, effective stress, seabed deformation, structure displacement and liquefaction potential in the seabed were estimated. From the results of the analysis, the stability of the vertical revetment was evaluated.

• Journal of Wetlands Research
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• v.11 no.2
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• pp.67-76
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• 2009

The contribution of pollutant loadings from non-point source (NPS) to the four major rivers in Korea exceeded 22~37 % of the total loadings in 2004 and is expected to reach 60 % in 2020. Most of NPS loadings are coming from urban areas, especially from paved areas. Because of high imperviousness rate, many types of NPS pollutant are accumulating on the surface during dry periods. The accumulated pollutants are wash-off during a storm and highly degrading the water quality of receiving water bodies. For this reason, the Korean Ministry of Environment (MOE) developed the Total Maximum Daily Load (TMDL) program to protect the water quality by managing the point source and NPS loadings. NPS has high uncertainties during a storm because of the characteristics of rainfall and watershed areas. The rainfall characteristics can affect on event mean concentrations (EMCs), mass loadings, flow rate, etc. Therefore, this research was performed to determine EMCs for rainfall ranges from transportation landuses such as road and parking lot. Two sites were monitored over 45 storm events during the 2006/06 through 2008/10 storm seasons. Mean TSS EMCs decrease as rainfall ranges increase and highest at less than 10mm rainfall. The results of this study can be used to determine the efficient scale of BMP facility considering specific rainfall range.

• Clean Technology
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• v.27 no.1
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• pp.39-46
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• 2021

A road structure washing vehicle equipped with a 4 HP, 80 LPM ultrafine bubble generator was used to clean a tunnel wall and the surface of the surrounding structure, consisting of concrete and tiles, in a heavy traffic area around an apartment complex in the city. Ultrafine bubbles were generated by supplying air at 2 to 3 LPM and using a specially designed nozzle, whereas fine bubbles made by an impeller in a gas-liquid mixing self-priming pump were produced with an average diameter of 165.4 nm and 6.81 × 107 particles mL-1. Using a high pressure washer gun that can perform high-pressure cleaning at 150 bar and 30 LPM, ultrafine bubbles were used to wash dust adsorbed on the surface of the road structures. The experimental analysis was divided into before and after washing. The samples were analyzed by applying ISO 8502-3 to measure surface contamination of dust adsorbed on the surface. Using the transparent tape attached to the surface, the removal rate was calculated by measuring the weight of the dust, and the number of particles was calculated using the gravimetric method and the software, ImageJ. The results of the experiment showed that the number of dust particles adsorbed on the tile wall surface before and after washing were 3,063 ± 218 particles mL-1 and 20 ± 5 particles mL-1, respectively, with weights of 580 ± 82 mg and 13 ± 4 mg. Particles on the surface of the concrete structure before and after washing were 8,105 ± 1,738 particles mL-1 and 39 ± 6 particles mL-1, respectively, with weights of 1,448 ± 190 mg and 118 ± 32 mg.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.6
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• pp.788-799
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• 1999

This study was performed to investigate the effect of mordants on the dyeability colorfastness to light and to laundering and biological properties of mordanted and natural-dyed cotton and silk substrates. Natural red dyes were extracted from Caesalpinia Sappan L. (Sappan wood) and Rubia Akane Nakai (Madder) by boil water Five different compounds of Al, Cr, Cu, Fe and Sn were used as mordanting agents. The result of this study are sumarized as follows ; 1. In the of the fabrics mordanted and dyed with sappan wood K/S value increases and λmax shifts to the longer wavelength as mordant concentration increases. Color of the fabrics dyed with sappan wood and madder change to redder bluer and lighter after mordanting. 2. As the number of repetition of dyeing-mordnating process increase the color of the dyed fabrics tend to be redder bluer and darker. Mordanted dyes with Al and Sn make chroma increase. The quantity of mordant absorbed in the silk fabric increase as mordant concentration increase. More Fe is absorbed in silk than Cr is. 3. After being exposed to light the fabrics dyed with sappan wood and madder change to less red Fe and Cu mordanting yeild better colorfastness to light than others does. Natural-dyed fabrics exposed to light tend to be faded and whitened in CIELAB chromaticity co-ordinates. So we might trace back the original color of ancient faded fabrics by changes in color of natural dyes. 4. After washing the colors of natural dyes change to more blue, Fe and Cu mordanting give better colorfastness to wash than others do. 5. The soil-burial cotton is more susceptible to mildew and rot than the silk is. Antimicrobial activity of the natural-dyed cotton can be enhanced by Cu and silk can be enhanced by Cu and Cr mordanting respectively.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.241-250
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• 2012

Objectives: This study was performed to investigate hygienic behavior of food handlers and general population focusing on awareness of hand-washing and the microbial load of their hands. Methods: A questionnaire survey and microbiological analysis were carried out for sixty-four people each. Samples for microbiological analysis were collected through the glove-juice method from the hands, and were analyzed for the presence of aerobic plate counts, total coliform, fecal coliform, Escherichia coli, Staphylococcus aureus, and Salmonella spp. according to the Food Code of Korea. Results: In the survey, significant differences between the food handlers and general population (p < 0.01) were found in hand-washing frequency, duration, use of hand-washing agents, washing parts of hands, hand-drying method, and method of turning off water. In eight different situations among the ten particular situations in their daily life, more food handlers responded to wash their hands than general population (p < 0.05). Bacterial load on hands with general population was consistently higher than with food handlers (p < 0.05), however, percentages of positive hands of S. aureus and Salmonella spp. were not. Conclusions: Poor hand hygiene practices were indicated by the positive results for E. coli, S. aureus, and Salmonella spp. on the hands of some respondents in both groups. This study reveals that there is the need for programs or campaigns to increase hand-washing practices of both groups.

• Textile Coloration and Finishing
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• v.23 no.4
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• pp.263-273
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• 2011

Digital textile printing(DTP) technology made considerable advances in recent years. In this study, a pre-treatment agent has been prepared for the better coloration of digital textile printing. The ink formulation contained three kinds of 5g thickener (CMC, Sodium alginate, Dextrin), 25g urea, 5g sodium carbonate, and 465g distilled water. The optimal sharpness of outline was found in the 1-3% concentration of the pre-treating agent with a viscosity of 10-15 cSt. Even if the color difference between untreated and treated samples was not apparent in the printing step, the color appearance increased after steaming. The color appearance of cyan, magenta, yellow, black reactive colorants increased in the order of CMC>Sodium alginate>Dextrin. Wash fastness to shade change and staining for the treated samples were 4-5 rating, while untreated sample was 1-2 rating. Also, the pre-treated sample with 1:1 mixtures had 4-5 rating. Both dry and wet rubbing fastness to shade change and staining were excellent in the treated samples, whereas rubbing fastness of untreated sample was 1-2 rating. With exception of 3 rating to black color, light fastness properties were 4 rating for the remaining three colors in the regardless of treatment condition and mixing of pre-treating agents. Dry cleaning fastness of all samples were also 4-5 rating irrespective of treatment condition and mixing of pre-treating agents.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.6
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• pp.487-495
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• 1997

The most desirable diesel oxidation catalyst (DOC) should have the properties of oxidizing CO, HC and SOF effectively at low exhaust gas temperature while minimizing the formation of sulfate at high exhaust gas temperature. Precious metals such as platinum and palladium have been known to be sufficiently active for oxidizing SOF and also to have high activity for the oxidation of sulfur dioxide $(SO_2)$ to sulfur trioxide $(SO_3)$. There is a need to develop a highly selective catalyst which can promote the oxidation SOF efficiently, on the other hand, suppress the oxidation of $SO_2$. In this study, a Pt-V catalyst was prepared by impregnating platinum and vanadium onto a Ti-Si wash coated ceramic monolith substrate. A prepared Pt-V catalytic converter was installed on a heavy duty diesel engine and the effect of fuel sulfur on particulate matter (PM) of heavy duty diesel engine was measured. The effect of fuel sulfur on PM of Pt-V was also compared with that of a commercialized Pt catalyst currently being used in some of the heavy duty diesel engines in advanced countries. Only 1 $\sim$ 3% of sulfur in the diesel fuel was converted to sulfate in PM for the engine without catalyst, but almost 100% of sulfur conversion was achieved for the engine with Pt catalyst at maximum loading condition. In the case of Pt-V catalyst, there was no big difference in conversion with the base engine even at maximum loading condition. The reason of SOF increase according to the increase of suflate emission was identified as the washing off effect of bound water in sulfate.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11a
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• pp.76-100
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• 2000

A brief general discussion of the nature and function of biosensors is presented. While the primary motivator for biosensor development has been the health-care industries, recent research efforts have spread to problems in agriculture and biological production systems. To illustrate some of the research from our laboratory, three example biosensors and their corresponding applications are presented. The first of these is an immunosensor for measurement of the hormone progesterone during milking as a method to improve reproductive management of dairy herds. The second example is an enzyme sensor for measurement of urea in milk as a menas to determine the efficiency of conversion of input protein to milk protein and, thus, improve nutritional management of dairy herds. The third example is a DNA sensor using polymerase chain reaction to detect pathogenic bacteria in the wash water of fresh and minimally processed fruits and vegetables. The potential for application of biosensors in agriculture, agrobiotechnology, food processing, and environmental monitoring has barely been realized.

• Korean Institute of Interior Design Journal
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• v.20 no.3
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• pp.182-189
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• 2011

This research suggests a way of hygienic space planing of the customer space in the university student restaurant of E University in Seoul. For this study. the behavior observation in the restaurant was conducted in order to analyze the sequence of customer behavior related space planing applying HACCP (Hazard Analysis And Critical Control Point). Also the survey was conducted to analyze opinions of customers about hygiene of the space. The results of the analyses of the observation and the survey were similar in terms of hygiene. In conclusion, for hygienic space planing of the customer space in restaurant, the space circulation should be planned according to the hygienic sequence of customer behavior. The spaces in restaurant should be divided into two areas: the clean area and the contaminated area to prevent cross-contamination. The clean area, such as spaces preparing dishes and food including water and table hall where customers eat, should be separated from the contaminated area such as the spaces where waste is handled and where dirty dishes are kept. In order to prevent cross-contamination, hygiene facility to remove contamination should be located before going to the clean area. More specifically, the hygiene facility should be located between a cash counter and a space preparing dishes so that customers can wash their hands before they touch dishes. Space arrangement with feed-back process to check the possible points of cross-contamination and correct space arrangement until the possibility of cross-contamination is removed in the restaurant.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1935-1940
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• 2009

This study investigates the actual wearing conditions of functional mountaineering garments in Korea and provides suggestions on the development of more effective functional mountaineering garments through the examination of consumer data. This survey was based on 107 respondents who enjoy mountaineering and was composed of 5 sections consisting of personal information, purchasing habits, essential features for mountaineering garments, satisfaction levels based on features and functions, and additional comments on the improvement of mountaineering garments. Respondents said that essential features for mountaineering garments are quick absorbing/drying, insulation, water and wind proof, and elasticity. These properties become more effective when users wear mountaineering garments in layers. They want lower prices and easy to wash garments. Therefore, it is necessary to consider not only the main functions, but also the needs of consumers for easy washing and price.