• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.357-360
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• 2005

Soil loss is widely recognized as a threat to farm livelihoods and ecosystem integrity worldwide. Soil loss prediction models can help address long-range land management planning under natural and agricultural conditions. Even though it is hard to find a model that considers all forms of erosion, some models were developed specifically to aid conservation planners in identifying areas where introducing soil conservation measures will have the most impact on reducing soil loss. Revised Universal Soil Loss Equation (RUSLE) computes the average annual erosion expected on hillslopes by multiplying several factors together: rainfall erosivity (R), soil erodibility (K), slope length and steepness (LS), cover management (C), and support practice (P). The value of these factors is determined from field and laboratory experiments. This study calculated soil erosion using GIS-based RUSLE model in Imha basin and examined soil erosion source area using SPOT 5 high-resolution satellite image and land cover map. As a result of analysis, dry field showed high-density soil erosion area and we could easily investigate source area using satellite image. Also we could examine the suitability of soil erosion area applying field survey method in common areas (dry field & orchard area) that are difficult to confirm soil erosion source area using satellite image.

• 정보보호학회논문지
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• 제19권4호
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• pp.63-75
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• 2009

해킹에 의한 개인정보의 유출 또는 기업의 관리 소홀로 인한 개인정보 유 노출 등의 침해사고가 다양한 형태로 발생하고 있으며, 이로 인한 피해범위도 확대되고 있다. 개인정보 유 노출 사고의 발생시 기업의 손실비용을 산출하는 일은 정보보호 투자에 대한 의사결정을 위해 필요하다. 본고는 개인정보 유 노출 사고로 인한 기업의 직접적이고 정량적인 손실비용 산출방안을 제시하고자 한다. 먼저 개인정보 침해사고에 의해 발생할 수 있는 손실비용을 범주에 따라 분류하고, 비용을 구성하는 요소들을 구체적으로 분석하였다. 또한 제시된 모형으로 2005${\sim}$2007년 동안 국내에서 발생한 개인정보 유 노출 사고의 손실을 추정하였고, 이를 일본의 사례와 비교 분석하여 시사점을 도출하였다.

• 대한치과보철학회지
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• 제42권4호
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• pp.458-470
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• 2004

Statement of problem: Br${\aa}$nemark or ITI are two currently most widely used implant systems but with contrasting design, surgical and restoration methods. Purpose: The purpose of this study was to compare changes and its statistical significance in bone height and shape which may rise due to the differences between two implant systems. Also to analyse the effect of inter-implant distance on annual bone height changes. Material & Method: Those patients who were treated with two or more of either Br${\aa}$nemark or ITI implants at posterior mandibular area at Yonsei University Dental Hospital, Implant Clinic were selected. At annual examination appointments, standardised radiographs using parallel technique were taken. Marginal bone and inter-implant crestal bone changes were measured and following results were obtained. Results: 1) When ITI and Br${\aa}$nemark system were compared, both annual marginal and inter-implant crestal bone height changes in ITI system in the first two years were smaller than Br${\aa}$nemark and they were statistically significant. On the third year, however, there was no statistical difference between two implant systems on their annual bone level changes (p>0.05). 2) The Marginal and inter-implant crestal bone changes were compared when inter-implant distance was less than 4mm. Statistically significant bone level changes were noted on the first year only for ITI implants but in the first and second year for Br${\aa}$nemark implants (p>0.05). 3) When comparing angulation changes between marginal bone and implant fixture, ITI system had smaller angulation changes but the annual changes were not statistically significant (p>0.05). Conclusion: Within the limitation of this study, it could be concluded that Br${\aa}$nemark implant systems had more changes in marginal and inter-implant crestal bone level in the first and second year after loading with statistical significance. Further studies are recommended to see the effects of these bone loss during the first and second year after loading on the long term prognosis of Br${\aa}$nemark Implants.

• 한국지리정보학회지
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• 제6권4호
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• pp.24-36
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• 2003

본 연구는 유역규모에서의 토양침식위험도를 평가하기 위해서 GIS 및 수정범용토양유실공식(RUSLE)을 활용하였다. 토양유실량 예측공식인 RUSLE 인자를 생성하기 위하여 토지이용도, 지형도, 토양도, 그리고 강수량 등의 자료들을 사용하였고, 최종적으로 grid 기반의 10m 셀의 격자형 데이터로 구축한 RUSLE 인자들의 중첩분석을 통하여 연간 토양유실량을 예측할 수 있었다. 분석결과에 따르면, 대상지의 83.5%는 연간 토양유실량이 1ton/ha 미만으로 비교적 낮은 것으로 나타났으나, 농업지역은 30% 이상이 연간 토양유실량 10ton/ha 이상으로 다른 토지이용에 비해 토양침식위험도가 상대적으로 높은 것으로 평가되었다. 따라서 이들 지역에 대한 철저한 현장조사를 토대로 토양침식의 위험도를 최소화하기 위한 토양보전계획의 수립이 필요하리라 판단된다.

• 대한건축학회논문집:구조계
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• 제35권6호
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• pp.153-164
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• 2019

The presence of thermal bridges in a building envelope cause additional heat loss which increases the heating energy. Given that a higher building insulation performance is required in these cases, the heat loss via thermal bridges is a high proportion of the total heat energy consumption of a building. For the dry exterior insulation system that uses mullions and transoms to fix insulation and exterior materials such as stone and metal sheet, the occurrence of thermal bridges at mullions and transoms is one of the main reasons for heat loss. In this study, a dry exterior insulation system using the truss insulation frame (TIF) was proposed as an alternative to metal mullions. To evaluate the building envelope performance, structural, air-leakage, water-leakage, fire-resistance, thermal, and condensation risk tests were conducted. In addition, the annual energy consumption associated with heating and cooling was calculated, including the linear thermal transmittance of the thermal bridges. As a result, the dry exterior insulation system using TIF achieved the allowable value for all tests. It was also determined that the annual heating load of a building was reduced by 36.7 % when the TIF dry exterior insulation system was used, relative to the dry exterior insulation system using steel pipes without additional insulations.

• 상하수도학회지
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• 제35권3호
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• pp.237-246
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• 2021

The ILI, developed by the IWA (International Water Association), has been used in many countries as an indicator of water leakage. In Korea, the revenue water has been used as a performance indicator for waterworks although there is an opinion to replace it with the ILI. Hence, it has been necessary to investigate whether the ILI can replace the revenue water in Korea. The four main operating indicators (i.e., water service population, profit-loss ratio, fiscal self-reliance, and aged pipe rate) of 162 Korean waterworks were compared with the ILI with the linear regression method. Local water authorities with more than 1 million water service population, with more than 60% profit-loss ratio, more than 40% and less than 60% fiscal self-reliance, and more than 20% aged pipe rate showed meaningful correlation between the four parameters and the ILI. In the remaining cases, their correlations were little or weak. This means that using the ILI may not be an efficient method to represent the performance of the water supply system in Korea because of the lack of UARL (Unavoidable Annual Real Losses) data accuracy. To use the ILI in Korea, it will be required to carry out an additional research to accumulate reliable CARL (Current Annual Real Losses) and UARL data in the future.

• 대기
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• 제16권2호
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• pp.111-124
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• 2006

This study examines seasonal variability of the surface energy balance at the King Sejong Station, Antarctica, using measurements and estimates of the components related to the balance for the period of 1996 to 2004. Annual average of downward shortwave radiation at the surface is 81 $Wm^{-2}$ which is 37% of the extraterrestrial value, with the monthly maximum of 188 $Wm^{-2}$ in December and the minimum of 8 $Wm^{-2}$ in June. These values are relatively smaller than those at other stations in Antarctica, which can be attributed to higher cloudy weather conditions in Antarctic front zone. Surface albedo varies between ~0.3 in the austral summer season and ~0.6 in the winter season. As a result, the net shortwave radiation ranges from 117 $Wm^{-2}$ down to 3 $Wm^{-2}$ with annual averages of 43 $Wm^{-2}$. Annual average of the downward longwave radiation shows 278 $Wm^{-2}$, ranging from 263 $Wm^{-2}$ in August to 298 $Wm^{-2}$ in January. The downward longwave radiation is verified to be dependent strongly on the air temperature and specific humidity, accounting for 74% and 79% of the total variance in the longwave radiation, respectively. The net longwave radiation varies between 25 $Wm^{-2}$ and 40 $Wm^{-2}$ with the annual averages of 30 $Wm^{-2}$. Accordingly, the annual average energy balance is dominated by radiative warming of a positive net all-wave radiation from September to next March and radiative cooling of a negative net all-wave radiation from April to August. The net all-wave radiative energy gain and loss at the surface is mostly balanced by turbulent flux of sensible and latent heat. The soil heat flux is of negligible importance in the surface energy balance.

• 한국토양비료학회지
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• 제43권6호
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• pp.828-836
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• 2010

본 연구에서는 1:25,000 정밀토양도 등 가용한 공간자료를 이용하여 작성된 토양유실도를 이용하여 한강 상류지역 10개 중권역 108 소유역에 대하여 토양유실량 평가하고 토지이용별 토양유실 위험지역을 분석하였다. 대상유역 총 토양유실량은 895만 Mg $yr^{-1}$으로 예측되었으며, 면적당 평균 토양유실량은 6.1 Mg $ha^{-1}yr^{-1}$ 이었다. 중소유역 단위로 살펴보면 남한강지역이 북한강 지역의 유실량 뿐만 아니라 면적당 유실량이 더 많았다. 이는 북한강 권역의 경우 화강암 및 화강편마암이 주요모재인 반면에 남한강 권역의 경우 토양모재가 퇴적암지대를 많이 포함있어 토양침식성 인자 (K factor)와 경사인자 (LS factor)가 상대적으로 높고, 남한강 지역의 경우 농경지 토양이 상대적으로 많이 분포하고 있기 때문으로 판단된다. 대상유역의 토지이용별 연평균 토양유실량을 분석한 결과 산림/초지 > 밭 ${\gg}$ 도심/대지 ${\gg}$ 논 > 과수의 순로분석 대상유역 중 10.7%를 차지하고 있는 농경지에서 유실되는 토양의 추정량은 41.3%이였으며, 이중 6.2% 면적을 차지하는 밭이 40.6%으로 44.2%의 산림/초지와 비슷한 수준이었다. 한강상류지역 토양유실 위험성 평가시 분포형 토양침식지도와 항공사진을 비교한 결과 토양유실에 대한 공간인 정보를 확실하게 보여주고 있으며, 토양침식위험성은 남한강권역의 남한강 상류 (1001), 평창강 (1002), 충주댐 (1003) 권역에서 각각 토양침식위험성이 "보통" 이상으로 높은 지역이 각각 8.7%, 7.9%, 7.8%로 평균인 5.9%보다 높았으며, 이에 대한 보전방안이 강구될 필요가 있고 판단된다.

• Journal of Applied Biological Chemistry
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• 제42권1호
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• pp.29-33
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• 1999

The present study examined annual runoff loading of nitrogen and phosphorus in the paddy field from 1 May, 1997 to 30 April, 1998. In the investigated area, the amount of rainfall was 1,095.6 mm and 414.6 mm during cropping season and non-cropping season. The annual rainfall was 1,510.2 mm. The total amount of runoff water was 1,043.2 mm and 281.0mm during cropping season and non-cropping season, and the added total amount of runoff water during two seasons was 1,324.2 mm. The runoff loading of nutrients caused by runoff water was measured as follows. The total-N was 149.23 and $8.67kg\;ha^{-1}$ (total amount=$157.90kg^{-1}ha^{-1}yr^{-1}$), the ammonia-N 102.98 and $4.44kg\;ha^{-1}$ ($107.42kg^{-1}ha^{-1}yr^{-1}$), the nitrate-N 28.45 and $1.23kg\;ha^{-1}$ ($29.68kg^{-1}ha^{-1}yr^{-1}$), the total-P 4.16 and $0.38kg\;ha^{-1}$ ($4.54kg^{-1}ha^{-1}yr^{-1}$) during cropping and non-cropping season respectively. When the loss ratio was calculated based on amounts of chemical fertilizer, about 68.6% of nitrogen and 16.7% of phosphorus was lost by runoff from applied fertilizer amount.

• KIEAE Journal
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• 제16권1호
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• pp.29-36
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• 2016

Purpose: The purpose of this study is to present basic data which would be applied on the early stage of the architectural design. And that determines the introduction of the atrium by comparing and analysing the environmental performance of atrium building. Method: The building forms are classified into low storied building, middle storied building and high storied building. This study compares and analyses energy performance of the standard building without atrium and the atrium building which has one-side, two-side, three-side, four-side, and linear atrium by measuring of annual heating and cooling load with EnergyPlus. Result: As a result of the analysis of the relative annual heating and cooling load by building type, it is shown that the fluctuation of cooling load in low storied building is large because heat storage in atrium affects building, and the fluctuation of heating load in high storied building is large owing to the effect of external wall area of atrium which makes heat loss. Especially, it indicated the largest annual heating and cooling load in four-side atrium of low storied building, and in one-side atrium of high storied building.