• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.36-41
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• 2011

BIPV system that can alternate building envelope by making materials of PV module should be considered in initial design step for applying PV system efficiently in office building. Mean while, area of the building skin also increases as the number of floors increases, but the valid area that can apply BIPV system in effect decreases relatively. Despite of this weak point, installing BIPV system is still being evaluated as the only measure left that can reduce electronic energy consumption in the building. Therefore, the impact on building energy consumption according to the increase of the number of floors when BIPV system is applied in the building was analyzed. And it will be used as basic information for application of BIPV in office building. Conomic about application of BIPV is interpreted to be secured within the 10 story high. Forover the 11 floors, the methods of increasing the contribution ratio produced by BIPV system through the optimization of install angle and increase in install area of south, high efficiency should be considered. The ways to reduce basic load by integrated design with another renewable energy besides BIPV should be found. Later, the study on the total building energy comsumption with PV generation according to the various type of the basic load and ratio of the width and depth will be performed based on this study.

• Imaging Science in Dentistry
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• v.42 no.4
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• pp.237-242
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• 2012

Purpose: The objectives of this study were to survey the radiographic exposure parameters, to measure the patient doses for intraoral dental radiography nationwide, and thus to establish the diagnostic reference levels (DRLs) in intraoral dental X-ray examination in Korea. Materials and Methods: One hundred two intraoral dental radiographic machines from all regions of South Korea were selected for this study. Radiographic exposure parameters, size of hospital, type of image receptor system, installation duration of machine, and type of dental X-ray machine were documented. Patient entrance doses (PED) and dose-area products (DAP) were measured three times at the end of the exit cone of the X-ray unit with a DAP meter (DIAMENTOR M4-KDK, PTW, Freiburg, Germany) for adult mandibular molar intraoral dental radiography, and corrections were made for room temperature and pressure. Measured PED and DAP were averaged and compared according to the size of hospital, type of image receptor system, installation duration, and type of dental X-ray machine. Results: The mean exposure parameters were 62.6 kVp, 7.9 mA, and 0.5 second for adult mandibular molar intraoral dental radiography. The mean patient dose was 2.11 mGy (PED) and 59.4 $mGycm^2$ (DAP) and the third quartile one 3.07 mGy (PED) and 87.4 $mGycm^2$ (DAP). Doses at university dental hospitals were lower than those at dental clinics (p<0.05). Doses of digital radiography (DR) type were lower than those of film-based type (p<0.05). Conclusion: We recommend 3.1 mGy (PED), 87.4 $mGycm^2$ (DAP) as the DRLs in adult mandibular molar intraoral dental radiography in Korea.

• Journal of Practical Engineering Education
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• v.7 no.2
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• pp.113-117
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• 2015

In this academic paper, we introduce a bread board simulation which is developed based on HTML language. this program is developed because actual electronic practices have some problems. Electronic circuit practice using bread board is widely practiced in colleges or high schools in South Korea, but actual electronic circuit practice needs lots of consumable stuff, and they are needed to be purchased and managed continuously. Besides, composing complicated electronic circuit restricts the efficiency of studying. Therefore, we propose breadboard simulation program which helps to resolve those problems.

• Cartoon and Animation Studies
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• s.47
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• pp.81-101
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• 2017

The present study argues that film director Lee Ae-rim animation works depict the world of the grotesque and not only are important sociocultural phenomena but also hold the significance of humor and subversion. The grotesque exhibits the intriguing characteristics of expressing a perspective critical of the existing society through the sensibilities of minorities and is used broadly as a term not only in the aesthetic sense but also designating sociocultural phenomena. Although discussed separately in terms of Mikhail Bakhtin's carnival grotesque and Mary Russo's uncanny grotesque, the grotesque fundamentally rejects existing order and conventions and is externalized through unique expressions, thus opening up a rich possibility for rejection, humor, satire, transformation, and deconstruction of and regarding the authority of the mainstream. Although they constitute a fictional medium, animation films are social products as well so that they are affected by society, culture, and history and stand as important texts that must be interpreted in terms of the relationships between humans' instinctive desires and society and between the overall culture and artistic media. However, the rarity of grotesque portrayals in South Korean animation films also proves that it is a society where even problems that are in themselves sensitive must be manifested ingeniously on a conventional level. South Korean society has a unique history of colonialism and national division and is simultaneously in the unique situation of a society that has undergone growth at a nearly unprecedented rate. Consequently, the society exhibits closed yet dynamic particularity where everyday tension and rigidity, wariness of others and extreme competition are intertwined in a complex manner. Intensively analyzed in the present discussions, director Lee's animation films and are characterized mainly by grotesque images, nonlinear narratives, and vivid depictions. In such a context, these works not only are artistic products of South Korean society but also rejections of a rigid society and share the significance of the aesthetics of the carnival grotesque, which consists of subversive expressions directed at a new world.

• Korean journal of communication and information
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• v.50
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• pp.50-72
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• 2010

The purpose of this study was to investigate representation of media on Korean controversial historical incidents and its myth and ideology. Especially the authors paid attention to the MBC-TV Documentary which had dealt with many controversial issues in Korean society. Those issues had never been dealt by other Korean media before it began to do. Three episodes about the South-North Korea related issues were selected as main object of this study and were analyzed with various semiotic research methods, especially, paradigmatic analytical method, narrative analytic method and mythical analytic method. As a main result of this study, it was found that the Documentary tended to represent such controversial historical issues very differently from the previous representations of old newspapers'. Th e old newspapers tried to establish old myths; that is, 'myth of national crisis', 'myth of anti-communism', 'myth of scapegoat of college students', 'myth of intelligent agency's monopoly', 'myth of social stablization', etc, while the documentary changed to build up new myths; that is, 'myth of humanities', 'myth of peaceful unification', 'myth of freedom and democracy', 'myth of human rights, etc.' In short, it was concluded that the documentary was able to change some previous myths and ideologies through its changing representations.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.464-471
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• 2013

In this study, the resource efficiency and future metal resource requirement in photovoltaic (PV) production system were evaluated by using material balance data and life cycle assesment (LCA) method. As a result, in the resource efficiency of ferrous and non-ferrous metal, lead and tin had higher resource efficiency than other materials in all PV systems (SC-Si, MC-Si, CI(G)S, CdTe). In the resource efficiency of rare metals, gallium and rhenium in silicon system and rhenium and rhodium in thin-film system ranked as the first and second high resource efficiency. In case of rare earth metal, gadolinium and samarium took higher resource efficiency. The results of the future metal resource requirement in PV systems showed that 2,545,670 ton of aluminium, 92,069 ton of zinc, 22,044 ton of copper, 1,695 ton of tin and 31 ton of nickel will be needed by 2030 in South Korea, except resource recycling supplement.

• Journal of the Korean Vacuum Society
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• v.16 no.3
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• pp.161-166
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• 2007

Photovoltaic (PV) technology permits the transformation of solar light directly into electricity. For the last five years, the photovoltaic sector has experienced one of the highest growth rates worldwide (over 30% in 2006) and for the next 20 years, the average production growth rate is estimated to be between 27% and 34% annually. Currently the cost of electricity produced using photovoltaic technology is above that for traditional energy sources, but this is expected to fall with technological progress and more efficient production processes. A large scale production of solar grade silicon material of high purity could supply the world demand at a reasonably lower cost. A shift from crystalline silicon to thin film is expected in the future. The technical limit for the conversion efficiency is about 30%. It is assumed that in 2030 thin films will have a major market share (90%) and the share of crystalline cells will have decreased to 10%. Our research at Sungkyunkwan University of South Korea is confined to crystalline silicon solar cell technology. We aim to develop a technology for low cost production of high efficiency silicon solar cell. We have successfully fabricated silicon solar cells of efficiency more than 16% starting with multicrystalline wafers and that of efficiency more than 17% on single crystalline wafers with screen printing metallization. The process of transformation from the first generation to second generation solar cell should be geared up with the entry of new approaches but still silicon seems to remain as the major material for solar cells for many years to come. Local barriers to the implementation of this technology may also keep continuing up to year 2010 and by that time the cost of the solar cell generated power is expected to be 60 cent per watt. Photovoltaic source could establish itself as a clean and sustainable energy alternate to the ever depleting and polluting non-renewable energy resource.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.343-347
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• 2010

Heavy application of fertilizer and manure in excess from the optimum requirement for crop growth can increase phosphorus (P) accumulation and P release potential in soils. In this study, the relationship between soil test P and 0.01M $CaCl_2$ extractable P was analysed to evaluate the P release potential of agricultural soils under different land-use. The paddy, upland, plastic film house(PFH) soils were sampled from Tongyoung and Changnyeong, and Daegok areas in Gyeongnam province, respectively. With respect to the P accumulation, available P contents in upland and PFH soils were 619 and 796 mg $P_2O_5$/kg, respectively indicating that different land-use types can greatly impact soil P accumulation. As soil available P was increased in the paddy soil, the content of 0.01M $CaCl_2$ extractable P also linearly increased without change point. Comparatively, P threshold were detected at 520 mg $P_2O_5$/kg in both upland and PFH soils, indicating that P release potential were higher in these land-use systems. For reducing P release from agricultural soils, management of optimum P content is needed in soils possessing high P release potential. Further, the change point value, if it is to be used as an environmental indicator, requires more detailed investigation to cover a wide range of soil characteristics.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.49-55
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• 1999

This study aims at analyzing environment factors of two tier cropping systems and suggesting effective structures of two tier cropping systems. The environment factors in two tier cropping systems are temperature, relative humidity, solar radiation, temperature of nutrient solution, and wind velocity. Especially, The most important factors are the solar radiation and the solar incident area between the two tiers. During the experiment, observations were made of the two levels in the plastic greenhouse. The highest temperatures were 38.3$^{\circ}C$ in the top level and, 35.5$^{\circ}C$ in the bottom level, respectively. The temperature of the nutrient solution between the two levels showed little difference. The relative humidity in the top level was 60~7o% and that in the bottom 65~80%, exhibiting that the bottom is approximately 10% higher. Change of photosynthetic photon flux density and solar radiation both have a tendency to be similar. The wind velocities for both levels were recorded at 0.1m.s$^{-1}$ in the afternoon and 0.05m.s$^{-1}$ in the evening. The solar incident areas in the bottom level increased by approximately 25% at an East-West position and 17.7% at a South-North position, respectively.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.117-122
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• 1997

The conditions of cold storage of Citrus unshiu Marc. var. miyagawa produced in Cheju were investigated. Compared to the citrus fruits stored at room temperature, the content of soluble solids, total sugar, vitamin C and specific gravity decreased slightly on the fruits stored at $4^{\circ}C$ and 87% relative humidity. Decay ratio and weight loss were below 10% on keeping freshness relatively till late of March during cold storage. Weight loss, decrease of firmness and soluble solids occured gradually during cold storage. Nevertheless seal-packaging with 0.02 mm LDPE film or wax-coating of citrus fruits were effective on weight loss and appearance, decay ratio increased for long-term storage. It was needed to control humidity in cold chamber for preventing from decay and weight loss. Edible part ratio was decreased gradually by respiration, and peel and tissue of fruits were softened slightly by 60 days of cold storage. Decay ratio and weight loss of full-ripened citrus fruits were little during the storage for 100 days, compared to the fruits harvested early. Appearance and taste of citrus fruits stored for 4 month were good relatively, but decay occured rapidly on seal-packaging fruits putting out of cold room for a few days. Because of the difficulty of long-term storage for early variety of Citrus unshiu, the conditions and periods of cold storage would be determined after considering the physicochemical properties of fruits.