• KIEAE Journal
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• 제12권1호
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• pp.99-104
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• 2012

In event of selecting construction materials, taking ones found easily around make embodied energy saved. The earth construction could be an eco-friendly engineering from a views of keeping the embodied energy. The pour earth method construction, as one of earth constructions, improves liquidity of earth-mixed properties to build walls or foundations. This study is aimed at evaluating possibilities as to machinery constructions using pumping cars or excavators to be applied on natural non-dried earth which are purchased from sites neighboring to subject building. The study showed that the pumping car used construction was smoothly carried out without any remarkable difficulties and further, a compressed strength was found to keep a certain degree to possibly construct low-story buildings. However, it showed some different levels as to a compressed strength by locations of buildings. In the construction course, we couldn't use remicon plants or a remicon due to field conditions and we are forced to take excavators in compounding or mixing works. But, it is evaluated that actually liquidity or compressed strength will be better than in case of using machineries like remicon plants. These results make us determine that the wall construction using machineries is possible.

• KIEAE Journal
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• 제7권6호
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• pp.91-97
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• 2007

This research examines the characteristics of the "rammed earth form" based on the criteria for the selection of forms. For this purpose, the paper first reviews the characteristics and orientation of the earth-construction and looks into the outline, the prerequisite, the current status and the tendency of the rammed earth form system through previous studies. Consequently, we aims to contribute to the criteria for the selection of rammed earth forms in the future through a comparative analysis of the construction cost, quality, safety and easiness of works between the veneer board form and the euroform, which are most widely used at earth housing project in the domestic country. The results reveals that the euroform is better than the veneer board with 21% of total cost in the cost analysis. But this better than that in the side of easiness of construction. In both cases, the buckling of wall panel form and the labor-oriented characteristics of the methods are the future research issues in the rammed earth form system.

• 한국농공학회지
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• 제45권6호
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• pp.83-95
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• 2003

In this study, a new concept in a paddy consolidation project is introduced in that curved parallel terracing with contour-lined layout is adopted in sloping areas instead of conventional rectangular terracing. The contoured layout reduces earth-moving considerably compared to rectangular methods in consolidation projects. The objective of the paper is to develop a combinatorial optimization model using the network theory for the design of contour-lined plots which minimizes the volume of earth moving. The results showed that as the length of short side of plot is longer or the land slope is steeper, the volume of earth moving for land leveling increases. The developed optimization model is applied for three consolidated districts and the resulting optimal earth moving is compared with the volume of earth from the conventional method. The shorter is the minimum length of short side of a polt with increases the number of plots, the less is the volume of earth. As the minimum length of short side is 20 m for efficient field works by farm machinery, the volume of earth moving of optimal plot is less by 21.0∼27.1 % than that of the conventional consolidated plots.

• KIEAE Journal
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• 제13권6호
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• pp.137-143
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• 2013

The purpose of this study is to suggest optimum micro-filler experiment method to select the optimal particle size of earth for using in earth construction works and test this suggestion through compressive strength measurement. According to the results of selecting the method to choose the optimum micro-filler mixing of earth and sand, three-stage filling(plate tamping) showed relatively high results and so was estimated to be the proper filling method. According to the results of optimum micro-filler experiment of earth and sand by the maximal sizes of sand, between 80% and 90% showed the highest result values. The larger the maximum size of sand was, the lower the addition ratio of sand was in optimum micro-filler mixing. According to the results of compressive strength experiment by the particle sizes of earth and sand, 90% in the addition ratio of sand showed the highest results, and so tended to be similar to the results of unit volume weight experiment.

• 한국경영과학회지
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• 제22권4호
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• pp.37-50
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• 1997

We consider the channel allocation problem for the earth orbit (LEO) satellite systems. This problm is known to be NP-complete and a couple of heuristic algorithms have been developed. In this paper, we convert the problem into a simpler form through the concept of pattern. And we suggest another algorithm based on Simulated Annealing for this simplified problem. The results of performance comparison show that our method works very well. Simulation results are reported.

• 한국농공학회지
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• 제13권3호
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• pp.2372-2387
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• 1971

평균적기온(平均的氣溫) $3^{\circ}C$이상(以上)의 일수(日數)는 표20에서 보는 바와 같이, 최고(最高) 365일(日)로서 제주(濟州)이고, 다음이 부산(釜山)으로 334일(日) 그리고 해안지역(海岸地域)인 울산(蔚山), 포항(浦項), 목포(木浦), 여수(麗水) 및 울릉도(鬱陵島)가 306일(日)이고 기타(其他) 대구(大邱), 광주(光州) 이북(以北) 지역(地域)은 공(共)히 275일(日)로 최고(最高)와 최하(最下)는 90일(日)의 간격(間隔)이 있다. 2. 토공(土工)(전압(轉壓))작업(作業)에 영향(影響)을 미치는 동토기간(凍土期間)은 표-22에서 보는 바와 같이 1년(年) 365일(日)에서 표-26(1)항(項)의 일수(日數)를 감(減)하면 된다. 3. 월평균기온(月平均氣溫) $3^{\circ}C$이상(以上)의 일(日) 중(中)에서 1mm이상(以上)의 강우일수(降雨日數)는 토공(土工)(전압(轉壓))작업(作業)에 영향(影響)을 미치는 요소(要素)로서 표-18에서 보는 바와 같이 최고(最高)는 100(日)로서 제주(濟州)이고, 최하(最下) 60일(日)은 대구(大邱)이다. 타지역(他地域)은 거의 모두가 70일(日) 내외(內外)이고 다만 울릉도(鬱陵島)만이 90일(日)이다. 4. 년중(年中) 토공(土工)(전압(轉壓))가능일수(可能日數)(4)는 표-26에서 보는 바와 같이 월평균기온(月平均氣溫) $3^{\circ}C$이상(以上)의 일수(日數)(1)에서 이 기간중(期間中)의 1mm이상(以上)의 강우일수(降雨日數)에 1.27(토공지장계수(土工支障係數)을 승(乘)한 값(3)을 감(減)하면 [(1)-(3)=(4)] 된다. 5. 지역별(地域別) 년중(年中) 토공(土工)(전압(轉壓))가능일수(可能日數)는 최고(最高) 242일(日)로서 부산(釜山)이며 다음은 제주(濟州)로서 239일(日), 기타(其他)는 181일(日)${\sim}$218일(日) 양(郞) 200일(日) 내외(內外)로 되어 있다.

• 자원환경지질
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• 제16권2호
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• pp.79-81
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• 1983

The effeet of the mass of the earth's atmosphere for gravity is studied. The computed correction value of the air mass effect is g=+0.86-0.0978 h (km) mgal and has always positive sign. In comparision with usual gravity works. this value is relatively large. So that, all gravity works always carry out this correction.

• 터널과지하공간
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• 제5권3호
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• pp.223-229
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• 1995

During excavation works for underground facilities, temporary tieback wall with earth anchor system was investigated for safety's sake. An excavation 9.7 meter deep was monitored by slope inclinometer in twelve measuring points. Instrumented lateral displacements of the wall during 177 days are represented. Especially, lateral displacements of the two positions under completely different condition are compared to investigate the effect of backfilling between soldier pile and the soil behind wall. The deformation behaviors of the wall according to both depth and elasped time are discussed. Finally, a numerical analysis by the program FLAC was performed, and calculated displacements are compared to measured ones.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2011년도 한국우주과학회보 제20권1호
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• pp.30.1-30.1
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• 2011

We present construction of 3D Earth optical Model for in-orbit performance prediction of L1 halo orbiting earth remote sensing instrument; the Albedo Monitor and Radiometer (Amon-Ra) using Integrated Ray Tracing (IRT) computational technique. The 3 components are defined in IRT; 1) Sun model, 2) Earth system model (Atmosphere, Land and Ocean), 3)Amon-Ra Instrument model. In this report, constructed sun model has Lambertian scattering hemisphere structure. The atmosphere is composed of 16 distributed structures and each optical model includes scatter model with both reflecting and transmitting direction respond to 5 deg. intervals of azimuth and zenith angles. Land structure model uses coastline and 5 kinds of vegetation distribution data structure, and its non-Lambertian scattering is defined with the semi-empirical "parametric kernel method" used for MODIS (NASA) missions. The ocean model includes sea ice cap with the sea ice area data from NOAA, and sea water optical model which is considering non-Lambertian sun-glint scattering. The IRT computation demonstrate that the designed Amon-Ra optical system satisfies the imaging and radiometric performance requirement. The technical details of the 3D Earth Model, IRT model construction and its computation results are presented together with future-works.

• 대한공간정보학회지
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• 제18권1호
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• pp.63-72
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• 2010

본 연구에서는 단지 설계과정 중 토공사의 효율성을 증진시키고, 토공계획에서 시공에 이르는 연결방안으로 3차원 지형공간기반의 토공모델링에 의한 설계가 가능하도록 토공설계 프로그램을 제작하였다. 토공량 산정시 측량자료를 3차원 격자 DEM을 작성하여 정밀한 토공량 산정을 가능하게 하였고, 이를 기반으로 토공이동과 장비활용이 가능하도록 토적표를 구성하였다. 토공작업에 소요되는 각종 건설장비의 재원을 고려하여 이동토량 및 경로가 표시되도록 하였으며, 공사진행상황파악이 가능하도록 open API 기반의 KML 형식으로 결과를 저장하여 3차원 가시화의 직관적 이해를 높이고 분석 결과의 공유가 용이하도록 제작하였다.