• Journal of the Korean Solar Energy Society
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• v.35 no.5
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• pp.57-65
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• 2015

The Potential Induced Degradation(PID) in PV module mainly affected by various performance conditions such as a potential difference between solar cell and frame, ambient temperature and relative humidity. The positive charges as sodium ions in front glass reach solar cell in module by a potential difference and are accumulated in the solar cell. The ions accelerate the recombination of generation electrons within solar cell under illumination, which reduces the entire output of module. Recently, it was generally known that PID generation is suppressed by controlling the thickness of SiNx AR coating layer on solar cell or using Sodium-free glass and high resistivity encapsulant. However, recovery effects for module with PID are required, because those methods permanently prevent generating PID of module. PID recovery method that voltage reversely applies between solar cell and frame contract to PID generation begins to receive attention. In this paper, PID recovery tests by using voltage under various outdoor conditions as humidity, temperature, voltage are conducted to effectively mitigate PID in module. We confirm that this recovery method perfectly eliminates PID of solar cell according to repeative PID generation and recovery as well as the applied voltage of three factors mainly affect PID recovery.

• Land and Housing Review
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• v.10 no.4
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• pp.13-30
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• 2019

Parking lot within housing site contains public interest of relieving parking space shortage problem and subject to public restriction. If auctioned off at higher price by excessive competition in general competitive bid for land bidders, the development of parking lot will be made against its original purpose supply. The core issue is that a bid price is quite often to be blown out of proportion by 150%~ 250% due to extreme competition and, could face serious problem if a winning bidder runs sale business. If it is rental business, although about 30% of the total floor space of the whole building to be used as neighborhood facilities, too high winning bid price cause to lose transparency. In case of sale at aggregate buildings, most business operators would sell 30% of the neighborhood facilities, spare the parking lot and manages thereof separately. According to Aggregate Buildings Act, neighborhood facilities are allowed for individual registration and ownership of parking lot by business operator or designated person by business operator. In this case, the parking lot becomes 70% of the total floor space of the whole building and 70% of the land share which makes the mortgage very valuable and easier for business operator to get financial loan. There used to be many cases such as owners of neighborhood facilities (aggregate buildings partial owners) who run parking lot to repay their loan running parking lot to repay loan, but found that very tough and reached auction and relatively disadvantaged. For parking lot within housing site, it is recommend to exclude the public factors that land has and take into account of public restriction in area (housing site). Business opportunity for operators and protection of property rights for buyers in aggregate buildings, land supply method is recommended to replace from highest bid method into draw or private contract. In terms of price, supply at estimated price (construction price) and restriction on usage (Co-ownership of parking lot) proposals are submitted.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2749-2757
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• 2014

The purposes of the study are to understand how multicultural efficacy is different and to affecting the multicultural efficacy. To achieve the goals, the study conducted surveys to examine an interrelation of multicultural efficacy on 272 elementary school students in Namyangju-si with questionnaires. First, the results showed that multicultural efficacy of elementary school students scored 2.84 on five point scale. Second, the elements that affected multicultural efficacy of elementary school students include 'openness', 'acceptance', 'respect' of elementary school student toward multiculture awareness, at the same time, elementary students' indirect experience of multiculture and direct experience also make significant influence. The study suggests to develop multiculture-related educational programs, in order to enhance multicultural efficacy and multicultural awareness of elementary students.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.338-345
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• 2007

This study surveyed on the actual conditions of using sanitizers and disinfectants for improvements of sanitization on food utensils at 105 school and 20 industry foodservice operations. The questionnaire which was administered to 125 foodservices was used as a mail or visitation method. The answers of asking "Perception on temporary authorization system of sanitizers and disinfectants on food utensils" were 75% in contract managed school foodservices, 81.8% in self operated school foodservices, and 50% in industry. Main factors to choose sanitizers were sterilizing power (38.6%, 28.6%, 38.9%) and safety (32.6%, 46.1%, 33.3%) at every foodservices. Keeping ratio of sanitizers and disinfectants guidelines in contract managed school, self operated school and industry foodservices were 64.8%, 52% and 73.7%, respectively. If easy and practical guideline is developed, most foodservices replied to use if for disinfection of foodservices. Most of the foodservices were not only knowing sanitizers and disinfectants but also possessing a guideline. However, they didn't perform disinfection according to the guideline due to its complexity. Consequently, we suggest that it is necessary to provide an easy and practical "sanitizers and disinfectants guideline" and useful information.