• Food Science and Preservation
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• v.5 no.3
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• pp.239-246
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• 1998

Polyimide membrane system was designed for manufacturing nitrogen-enriched gas, and basic technical data was suggested for appling this system to controlled atmosphere storage. The permeability characteristics of pure oxygen and nitrogen could be explained by dual-mode sorption model. There was substantial decrease in the permeation rates of oxygen, which is the more permeable gas, through the polyimide membrane due to the presence of nitrogen in comparison with pure oxygen. However, the permeation rates of nitrogen was increased by the presence of oxygen. The ideal separation factor was in the range of 5 to 6 in the range of temperature and pressure difference studied, and the separation factor of air was lower than the ideal separation factor. The increase of ideal separation factor with increasing temperature is due to the fact that the activation energy for oxygen is larger than that for nitrogen. Nitrogen concentration decreased rapidly with increasing product recovery, and it was found that this is a major operating factor to obtain nitrogen concentration required for controlled atmosphere storage. A relation equation, by which nitrogen concentration in storehouse can be predicted, was suggested under the establishment of a hypothetical model for controlled atmosphere storage process using polyimide membrane system.

• Journal of the Ergonomics Society of Korea
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• v.35 no.1
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• pp.1-10
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• 2016

Objective: This study aimed to find good design for summer functional farm shoes under the agricultural environment and working characteristics, which can help safe farm work and further promote the efficiency of working. Background: Most accidents at farms were overturn accidents caused by slipping or falling, and it was found that the main factors which caused the overturn accidents were inappropriate work shoes for the working conditions. These inappropriate work shoes often cause overturn accidents in the rural areas with steep paths. Method: A survey on work shoes was conducted with 174 farmers, and the outcome of this survey was used to find problems of work shoes and improvement ideas for the design of work shoes which can be used at farms. Results: Regarding the form of farm shoes, the ankle height was set at 6 inches to prevent the bending of the ankle and the inflow of foreign substances. The size and groove of the pattern of the outsole were extended to prevent catching of foreign substances. In the upper part, polyurethane and cordura were used in combination to secure air permeability, which was pointed out as the reason for the discomfort during the work wearing existing work shoes. Conclusion: Since farmers felt discomfort with the shoes which they were currently wearing, this study suggested a design of farm shoes by analyzing the important matters of the work shoes in development in order to improve such discomfort. Application: This study can help develop farm shoes that would practically ease farmers' burden of working at farm worksites and keep them safe.

• Journal of Environmental Science International
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• v.25 no.6
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• pp.889-895
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• 2016

In Danseong-myeon (myeon is a subdivision of), Sancheong-gun, and Sugok-myeon, Jinju City, pot seedling culture was used at the rates of 100% and 62%, respectively. Root restriction seedling culture was used relatively more frequently than pot seedling culture in Yangchon-myeon, Nonsan City, Guryong-myeon, Buyeo-gun, and Wolsan-myeon, Damyang-gun. Open-field seedling culture was used at the rates of 80% and 54% in Samnangjin-eup (eup is a subdivision of a gun), Miryang City and Ssangnim-myeon, Goryeong-gun, respectively. In Danseong, Sancheong, and Sugok, Jinju, granite soil was used as the medium for pot seedling culture at the rates of 90% and 80%, respectively. In Yangchon, Nonsan, Wolsan, Damyang, and Ssangnim, Goryeong, commercial bed soil and coir dust were used for seedling culture at the rates of 73%, 64%, and 60%, respectively. At the main production sites, the use of granite soil for seedling culture, highest rate in 2000-2005, continued to decrease; in 2011-2013, granite soil was used at the rate of 37%, while commercial bed soil and coir dust were used at the rates of 32% and 14%, respectively. The bulk density of commercial bed soil, expanded rice hulls, and coir dust was $0.11-0.16g/cm^{-3}$. Coir dust was the lightest material but had the highest and, 36.7% and 21.8%, respectively. In sandy loam soil and granite soil was low. The pH of all growth media was between 5.4 and 7.0, and the values were in the range of $0.15-0.66dS{\cdot}m^{-1}$. However it was necessary, to adjust the pH levels and enhance the of expanded rice hulls, sandy loam soil, and granite soil. Similarly, the fertilizer concentration and air permeability of coir dust need to be adjusted.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.4
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• pp.191-195
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• 2017

The microstructures of nonwoven fabric with and without nanofibers used as a filter for air purification type mask were investigated using scanning electron microscope. Moreover, we proposed a new mask design which is effective in the improvement of the fine dust blocking property. When comparing to nonwoven fabrics of which an average diameter was $25{\mu}m$, the nanofibers formed by the electrospinning process had a tight mesh structure arranged irregularly with a relatively large specific surface area, which could be associated with their much smaller diameter ranging from 25 to 120 nm. Such a prominent structural feature at nanofibers led to mechanical adsorption of fine particles, resulting in enhancement of filtering behavior maintaining high permeability. In addition to the excellent performance of the mask filter, wearing the mask properly is expected to maximize the blocking property of fine dust. To meet such a requirement, a new mask design that can be closely attached to the face in order to effectively block fine dust entering the gap between the face and the mask.

• Journal of the Korea Concrete Institute
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• v.18 no.3 s.93
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• pp.371-378
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• 2006

Recently sewage facilities mainly consisted of concrete structures are being deteriorated seriously by biodeterioration originated from sulfur-oxidizing bacteria. In this study, to prevent biochemical corrosion of the sewer concrete, antibiotics which prevent growth of sulfur-oxidizing bacteria were developed and antimicrobial performance of it was investigated. After that, to consider applicability of antibiotics to concrete, physical properties of concrete covered with antibiotics were investigated. As a results of the study, it was proved that the antimicrobial performance of antibiotics was available. Also compressive strength and bond strength of concrete didn't closely connected with antibiotics, and resistance to abrasion, water absorption, air permeability, carbonation, salt damage and chemical attack of concrete was improved remarkably by covering with it.

• Fashion & Textile Research Journal
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• v.16 no.4
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• pp.645-652
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• 2014

This study identifies consumer needs and a pattern sensory evaluation of jacquard fabrics for raincoats using quick-drying-absorbing polyester. We investigate the consumer's consciousness and raincoat improvements. Twelve kinds of jacquard fabrics were developed for use in this study. Developed jacquard fabrics were assessed subjectively by 152 university students using a 7-point scale of 26 consumer needs and 31 pattern image sensory descriptors. Data were analyzed by SPSS. The major results were: There was a need for consumers to improve the front fastener type, cuff fastener, mesh patch position, and raincoat pocket position. The most important parameter to choose raincoat fabric was waterproof and the other parameters were vapor-porous/water repellent, design, color, fashionability, air-permeability and easy-put on/off. The pattern image sensibility of jacquard fabrics was explained by seven factors: gorgeous, simple, cute, futuristic, ethnic, feminine, and cool. A higher pattern preference was found in the jacquard fabrics of unique, sporty, natural, luxurious, and trendy images. The pattern preference was predicted at 45.3% with gorgeous, simple, pure, cute, futuristic factors. The correlation coefficient between the pattern image sensibility factor 1 (gorgeous) and pattern preference was 0.674 and with factor 3 (cute) was 0.416, and with factor 6 (cool) was 0.209. The 4 factors (gorgeous, simple, cute, futuristic) were selected as a significant pattern image sensibility that influenced preference.

• Fashion & Textile Research Journal
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• v.16 no.4
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• pp.614-624
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• 2014

This study is intended to offer basic data for developing outdoor clothing exported to China by identifying how Chinese consumers use outdoor clothing. To accomplish the objective, a survey was conducted on 300 male and female Chinese tourists in their 10s to 40s who have purchased outdoor clothing before. As more than twice as many respondents said they wear sweatsuit or everyday clothes for mountain-climbing instead of outdoor clothing, the necessity of outdoor clothing is obviously perceived at a low level. Among them, 57.4% wear outdoor clothing as townwear in everyday lives, and other respondents are dissatisfied with the design. Thus, it is necessary to develop townwear-style design. When buying outdoor clothing, wearability was the biggest consideration. Also, the first criteria for evaluating outdoor clothing was practicality for mountain-climbing activities. The functionality of outdoor clothing they needed the most was air permeability. As for outdoor clothing top, the main inconvenience was tightness around the neck. As for bottoms, it was tightness of pants when bending knees. In terms of areas to be improved, the No. 1 was unformed design. Thus, it is imperative to develop design of diverse styles. As the Chinese outdoor clothing market has grown significantly in recent years, the following should be executed by domestic companies before advancing to the market. First, they should form Korean brand image and boost the brand awareness with various activities, amid Korean Wave. Second, they should develop preferred designs among Chinese consumers and strengthen functionality of products, based on consumer survey.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.317-328
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• 2012

In this study, printing was introduced to the common dip-dyeing method of persimmon juice dyeing so as to develop two different colored persimmon juice dyed fabrics with printings of 'jorangmal' patterns (a national monument) instead of producing a plain textile. Following are the results of a comparative study between the persimmon dyed fabric and undyed fabric, both with printings, in terms of its properties, and hand values. Cotton and rayon were chosen as samples and were compared separately. Firstly, the samples showed differences in terms of clarity and visual sensation depending on the presence of persimmon dye, even if the same pattern and color was used. Secondly, the air permeability of two samples improved after persimmon dyeing even though their thickness increased, and their moisture regain increased as well in all humidity conditions. Thirdly, protectiveness against UV increased in dyed samples, and sweat, sunlight, and compound colorfastness improved in printed dye-fabrics compared to plain dyed ones. Therefore, printing proved to be effective in preventing discoloration. Fourthly, tensile linearity and resilience, bending rigidity, compressive linearity and resilience, and shearing stiffness increased more in the dyed samples compared to undyed ones. However, shearing recovery decreased in both dyed fabrics. Fifthly, the result of its hand value showed that Koshi value increased in all samples than undyed ones, whereas Fukurami, Numeri, and Softosa values decreased. Incorporating printing in persimmon dyeing process could expect creative outcomes not only in today's diverse fashion but in areas of arts or crafts as well.

• Journal of the Korean Society of Costume
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• v.57 no.3 s.112
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• pp.53-62
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• 2007

The purpose of this study was to investigate mechanical and comfort performances of the material for the improved working uniform for a volunteer fire brigade member, to get basic data for its evaluation and to help its material and design development. The results were as follows; The material of the newly developed working uniform was thinner and lighter than the material of the current used working uniform. It had better breathability, air permeability and heat transmission rate than the current one. It also had superior anti-flammability In all mechanical properties(tensile, bending, shearing, compression and surface properties), it showed better performances than the current one. It elongated and bended easier and more in both warp and weft directions. The elastic recovery and shape stability after elongation were also higher. The recovery and resistance to shearing and the resiliency and recovery after compression were also better than the current one. It was more flexible, softer and smoother in primary hand value, and was more suitable for the material for winter suit which needs softness and fullness in total hand value. The material of the improved working uniform showed lower thermal insulation value and higher evaporative resistance value compared to the material of the currently used working uniform from the sweating thermal manikin test. It was shown that the physical performances and the hand value of the textile material used in the newly developed working uniform for a volunteer fiber brigade member was improved compared to the one used in the currently used working uniform.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.427-435
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• 2012

In order to evaluate the effects of exposure conditions on the resistance to sulfate attack of normal and blended cement mortars, several mechanical characteristics of the mortars such as expansion, strength and bulk density were regularly monitored for 52 cycles under sodium sulfate attack. The mortar specimens were exposed to 3 different types of exposure conditions; 1) continuous full immersion(Exposure A), continuous half-immersion(Exposure B) and cyclic wetting-drying(Exposure C). Experimental results indicated that the maximum deterioration was noted in OPC mortar specimens subjected to Exposure B, showing the wide cracks in the portions where attacking solution is adjacent to air. Additionally, the beneficial effect of ground granulated blast-furnace slag and silica fume was clearly observed showing a superior resistance against sodium sulfate attack, because of its lower permeability and densified structure. Thus, it is suggested that when concrete made with normal cement is exposed to sulfate environment, proper considerations on the exposure conditions should be taken.