• Solar Energy
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• v.10 no.3
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• pp.66-78
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• 1990

The purpose of this study is to provide materials necessary for planning and designing of passive solar school buildings by comparing and analyzing the satisfaction degree on old passive solar school building environment characteristics according to the school building pattern. In conclusion, passive solar systems are effective and economical when they are applied to school buildings for heating systems.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.486-491
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• 2009

To evaluate the potential value of the major bioenergy crops which are wheat, canola, barley, corn, and sweet potato in Korea, we investigated the production of biomass and calorific value of crops, and also compared input and output factors among bioenergy crops during the cultivation period. There was difference between the biomass values in Agricultural and Forestry statistical yearbook(2006) and the one investigated in this experiment, also there was difference in crops and in species. Among the crops investigated, sweet potato(Jinhongmi, Yulmi) was shown the highest amount of biomass production and corn(Gangdaok) was shown the highest amount of the total biomass which is the total aboveground biomass at harvest. Oilseed canola which is presently a major source of bio-diesel had highest calorific value as $6,673{\sim}6,725cal\;g^{-1}$. Wheat and corn grains which are source of bio-ethanol were in the range of $3,879{\sim}4,317cal\;g^{-1}$. Gangdaok(Corn) produce the highest total calorific value in unit cultivating area among the crops as $8,263kcal\;m^{-2}$. Corn was shown that the input and output factors were the highest level among bioenergy crops during cultivation period. Sweet potato also was shown that output factor was the highest level though its input factors were average level. It is needed to be investigated more crops for collecting the higher potential value of bioenergy production further considering small land area and its effective utilization in Korea.

• Progress in Medical Physics
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• v.19 no.3
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• pp.164-171
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• 2008

One of the most important task in commissioning intensity modulated radiotherapy (IMRT) into a clinic is the characterization of dosimetry performance under small monitor unit delivery conditions. In this study, method of evaluating dose monitor linearity, beam flatness and symmetry, and MLC positioning accuracy using a diode array is investigated. Siemens Primus linear accelerator (LA) with 6 and 10 MV x-rays was used to deliver radiation and the characteristics were measured using a multi array diodes. Monitor unit stabilities were measured for both x-ray energies. The dose linearity errors for the 6 MV x-ray were 2.1, 3.4, 6.9, 8.6, and 15.4 % when 20 MU, 10 MU, 5 MU, 4 MU, and 2 MU was delivered, respectively. Greater errors were observed for 10 MV x-rays with a maximum of 22% when 2 MU was delivered. These errors were corrected by adjusting D1_C0 values and reduced to less than 2% in all cases. The beam flatness and symmetry were appropriate without any correction. The picket fence test performed using diode array and film measurement showed similar results. The use of diode array is a convenient method in characterizing beam stability, symmetry and flatness, and positioning accuracy of MLC for IMRT commissioning. In addition, adjustment of D1-C0 value must be performed when a Siemens LA is used for IMRT because factory value usually gives unacceptable beam stability error when the MU/segment is smaller than 20.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.2
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• pp.44-52
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• 2012

As an alternative strategy in the era of high level petroleum cost, the study focused to suggest the way on the revitalization of renewable energy through the impact on introduction effect of renewable energy in green village. Total feasible solar energy production is 6.73 GWh/yr along with the biomass energy producing electric power energy is 134.06 GWh/yr, the two category's total electric power energy is 233.19 GWh/yr, which is possible to achieve the selfsufficiency of energy by 33% for total energy consumption of 705.80 GWh/yr in the region. The calculated feasibility on the carbon dioxide reduction, carbon dioxide reduction level is 1,891 ton_$CO_2$ by agricultural byproducts, 43,635 ton_$CO_2$ by livestock waste, 395 ton_$CO_2$ by municipal waste, 50,324 ton_$CO_2$ by forest byproducts, the total biomass shows 96,245 ton_$CO_2$, while the carbon dioxide reduction of solar light energy is 2,251 ton_$CO_2$, 1,383.3 ton_$CO_2$ by solar heat energy, the total solar energy shows 3,634 ton_$CO_2$. So total carbon dioxide reduction effect shows 99,879 ton_$CO_2$.

• JOURNAL OF ELECTRICAL WORLD
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• no.6 s.2
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• pp.33-38
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• 1974

우리나라 남${\codt}$서해안선의 총 연장은 5,000천에 달하며 크고 작은 섬들만도 2,000여개가 산재하고 있다. 여기에 밀려드는 조석 및 파력에너지의 포장량은 전력으로 환산하여 줄잡아 $10^{8}KW$ Order의 ''이론적 포장에너지량''이 부존하고 있다고 생각된다. 수력의 경우 구주각국이나 일본에 있어서는 ''기술적 포장수력''의 $25{\~}50{\%}$가 ''기술적 포장수력''으로, 그리고 $10{\~}20{\%}$가 ''경제적 포장수력''이라는 통계치가 나와 있다. 조력의 경우 이와같은 수치를 그대로 적용할 수는 없겠지만, 수천만kw Order의 기술적 또는 경제적 포장능력이 우리나라 남서해안에 부존할 수 있음에 수긍이 간다. 이론적으로 포장량을 기술적 포장량으로 바꾸고 이를 다시 실현성있는 경제적 포장량화하는 원동력은 인간의 지혜 곧 ''기술''과 역사의 흐름 곧 ''시운''에 좌우된다고 하겠다. 정부는 국내 부존에너지자원의 활용 극대화를 위하여 ‘74년도 우리나라 서해안의 조력발전기초조사를 과학기술처 산하 ${\ulcorner}$한국해양개발연구소${\lrcorner}$를 중심으로 하여 실시하게 된다. 국내 관계기관 및 전문가들의 적극적 참여와 협조를 바란다.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.127-129
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• 2020

높은 에너지 밀도, 장 수명 등의 특성을 갖는 리튬계열 축전지는 다양한 어플리케이션에 활용되고 있다. 그러나, 리튬계열 축전지의 열화로 인한 출력 특성 저하는 원전 사고 시, 안정적인 전력 공급을 저해하므로 원전 적용을 위해서 리튬계열 축전지의 열화를 일으키는 방사선에 대한 리튬계열 축전지의 강건성 검토가 필요하다. 본 논문은 방사성 동위원소 Co-60, 총 방사선량 100Gy의 저 준위 방사선 조사 시험을 진행하였으며, 이에 따른 리튬계열 축전지의 특성 비교를 위해서 전기적 특성분석 방법을 이용하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.411-417
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• 2017

It is necessary to determine the current and future energy consumption by farm households for the rational specification of energy related policy in the Korean agricultural sector. Especially, It is important to identify the consumption by source of energy and by the crops. On the other hand, the world has tried to reduce the production of greenhouse gases and, in line with this, the Korean government established related legislations to contribute to this reduction (30% reduction in emissionsby 2020). The reduction target of the agricultural sector is specified as 5.2% of the national total. This study focuses on sampling design to determine the energy consumption and emission of greenhouse gases, and suggests several alternatives to improve the confidence level and to make a dent survey and estimation errors. The population for the energy consumption survey of the agricultural sector was derived from agricultural census data. In the case of commodities with high skewness, we cut the sample range to within the statistical significant range. The number of samples in each class is specified using the Neyman allocation method and 95% significance level. The estimation results are compared with the population to verify the statistical significance and several management methods of sampling errors are suggested.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.133.1-133.1
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• 2011

우리나라는 2012년부터 신재생에너지 공급의무화제도(Renewable Portfolio Standards, RPS)의 도입을 확정하였다(지식경제부 고시 제2010-244호). RPS 제도는 기존의 발전사업자에게 총 발전량 중 일정량 이상을 신재생에너지 전력으로 공급토록 의무화하는 제도이다. RPS의 도입을 통해 일차적으로 신재생에너지의 보급 확대를 도모할 수 있으며, 부차적으로 신재생에너지 공급확대의 비용의 소비자 귀착을 기대할 수 있다. 본 연구는 RPS 제도로 인한 신재생에너지 보급확대의 비용이 소비자에게 전가된다는 가정 하에, 조건부가치평가법(Contingent valuation)을 적용하여 신재생에너지 전력에 대한 지불의사액(Willingness to pay)을 분석하였다. 본 연구의 주된 목적은 신재생에너지 전력에 대한 지불의사액을 분석하는 데 있어 지역별로 어떠한 차이가 나타나는지 알아보는 데 있다. 이에, 서울, 울산, 강원도, 전라남도의 4개 지역을 설문대상 지역으로 선정하였다. 서울은 신재생에너지를 포함한 에너지 관련 시설에 대한 경험이 거의 없는 비교군에 해당하며, 강원도와 전라남도는 신재생에너지의 이용이 활발한 지역을 대표하는 대조군에 해당된다. 울산은 신재생에너지 이용이 활발하지는 않으나 굴지의 산업단지가 입지한 지역으로, 대형 에너지 관련 시설에 대해 특수한 선호를 보일 것이라 추측되어 대조군으로 선정하였다. 본 연구에서는 이 4개 지역의 주민들을 대상으로 조건부가치평가법을 적용한 설문조사를 시행하여 신재생에너지 전력에 대한 지불의사액을 도출한 후, 이를 비교 분석하였다. 본 연구결과를 통해 신재생에너지에 관련된 경험이 선호에 어떠한 영향을 미치는지 파악할 수 있으며, 도출된 신재생에너지 전력에 대한 지불의사액은 향후 RPS 정책 도입시 전기요금 산정 관련 논의의 참고자료로 활용될 수 있을 것으로 기대된다.

• Tunnel and Underground Space
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• v.24 no.6
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• pp.418-429
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• 2014

Induced seismicity related to four energy development technologies that involve fluid injection or withdrawal: geothermal energy, conventional oil and gas development including enhanced oil recovery (EOR), shale gas recovery, and carbon capture and storage (CCS) is reviewed by literature investigation. The largest induced seismic events reported in the technical literature are associated with projects that did not balance the large volume of fluids injected into, or extracted from the underground reservoir. A statistical observation shows that the net volume of fluid injected and/or extracted may serve as a proxy for changes in subsurface stress conditions and pore pressure, and other factors. Energy technology projects that are designed to maintain a balance between the amount of fluid being injected and the amount of fluid being withdrawn, such as geothermal and most oil and gas development, may produce fewer induced seismic events than technologies that do not maintain fluid balance, such as long-term wastewater disposal wells and CCS projects.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.383-391
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• 2021

To develop a cultivation method for the mass production of sweetpotato cultivars, 'Juhwangmi' (orange tuber) and 'Sinjami' (puple tuber), the yield of tuber roots and content of various functional substances were analyzed according to planting intervals and growing periods. For 'Juhwangmi, the total yield of tubers was increased by respectively 36% and 54% and the yield of tubers over 300 g was increased by respectively 170% and 221% in the 140-day and 160-day cultivation plots compared with that in the 120-day cultivation plot at the 70×20 cm planting interval. Similarly, the total content of beta-carotene in the tubers increased as the cultivation period was extended. In particular, beta-carotene content at the 70×20 cm planting interval was the highest. For 'Sinjami', at the same planting interval, the total yield of tubers and yield of tubers over 300 g significantly increased as the growing period was extended. Within the same cultivation period, the yield of tubers over 300 g and the total anthocyanin content of 'Sinjami' were higher at the 70×30 and 70×35 cm planting intervals than at the 70×20 and 70×25 cm planting intervals in the 140-day and 160-day cultivation plots. Moreover, the total polyphenol and flavonoid content was significantly higher in 'Sinjami' than in 'Juhwangmi', and the values were the highest in the 160-day cultivation plots. In particular, the content of these two functional substances in tubers over 300 g was the highest at the 70×30 and 70×35 cm planting intervals.