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A Study on Sustainable Earth Architecture Characteristic from Ecological Aesthetic Point of View - Focus on the thoughts of Lao-tzu - (생태미학적 관점에서의 지속가능한 흙건축 특성에 관한 연구 - 노자사상을 중심으로 -)

  • Kim, Seol-Hyi;Hur, Bum-Pall
    • Korean Institute of Interior Design Journal
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    • v.20 no.4
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    • pp.54-62
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    • 2011
  • Fast industrialization caused from Descartes' dichotomy has enormously developed our world, but endangered the ecosystem. In this study, the ecosystem aesthetics is not only a critique against existing growth-ideology and technical civilization, but also the art pursuing the life as an artistic state and achieving the dream for qualitatively different new future. Lao-tzu's Natural Beauty assumes that the adaptation to natural laws can lead every purpose's achievement. Based on such theoretical alternative, the earth construction as a medium for coexisting mankind, nature and construction interacts with the other objects through the natural affinity, the energy efficiency, the material generation. The earth construction provides the images of naivety, naturalness, folk as well as emotional stability in cultural terms. This study's direction and method are as follows. First, it researches the ecosystem aesthetics from the Taoism viewpoint, the alternative for environmental healing based on theoretical reviews about the ecosystem aesthetics. Second, it researches the earth construction's ecosystem aesthetic features and construction features from the low-tech aspect in continual construction genealogy. Third, it analyzes some cases targeting domestic buildings by drawing out expression methods and features through the connectivity of earth construction and ecosystem aesthetics. The earth construction lies between the heaven and the earth, but coexists in natural cycle. The earth construction caused from ecosystem aesthetics will be a future alterative, and various studies about its features and methods should be continued.

Study on critical buckling load calculation method of piles considering passive and active earth pressure

  • Chen, Yong-Hui;Chen, Long;Xu, Kai;Liu, Lin;Ng, Charles W.W.
    • Structural Engineering and Mechanics
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    • v.48 no.3
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    • pp.367-382
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    • 2013
  • Different types of long slender pile shall buckle with weak soil and liquefied stratum surrounded. Different from considering single side earth pressure, it was suggested that the lateral earth pressure can be divided into two categories while buckling: the earth pressure that prevent and promotes the lateral movement. Active and passive earth pressure calculation model was proposed supposing earth pressure changed linearly with displacement considering overlying load, shaft resistance, earth pressure at both sides of the pile. Critical buckling load calculation method was proposed based on the principle of minimum potential energy quoting the earth pressure calculation model. The calculation result was contrasted with the field test result of small diameter TC pile (Plastic Tube Cast-in-place pile). The fix form could be fixed-hinged in the actual calculation assuring the accuracy and certain safety factor. The contributions of pile fix form depend on the pile length for the same geological conditions. There exists critical friction value in specific geological conditions that the side friction has larger impact on the critical buckling load while it is less than the value and has less impact with larger value. The buckling load was not simply changed linearly with friction. The buckling load decreases with increased limit active displacement and the load tend to be constant with larger active displacement value; the critical buckling load will be the same for different fix form for the small values.

Mechanism of Seismic Earth Pressure on Braced Excavation Wall Installed in Shallow Soil Depth by Dynamic Centrifuge Model Tests (동적원심모형실험을 이용한 얕은 지반 굴착 버팀보 지지 흙막이 벽체의 지진토압 메커니즘 분석)

  • Yun, Jong Seok;Park, Seong Jin;Han, Jin Tae;Kim, Jong Kwan;Kim, Dong Chan;Kim, DooKie;Choo, Yun Wook
    • Journal of the Earthquake Engineering Society of Korea
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    • v.27 no.5
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    • pp.193-202
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    • 2023
  • In this paper, a dynamic centrifuge model test was conducted on a 24.8-meter-deep excavation consisting of a 20 m sand layer and 4.8 m bedrock, classified as S3 by Korean seismic design code KDS 17 10 00. A braced excavation wall supports the hole. From the results, the mechanism of seismically induced earth pressure was investigated, and their distribution and loading points were analyzed. During earthquake loadings, active seismic earth pressure decreases from the at-rest earth pressure since the backfill laterally expands at the movement of the wall toward the active direction. Yet, the passive seismic earth pressure increases from the at-rest earth pressure since the backfill pushes to the wall and laterally compresses at it, moving toward a passive direction and returning to the initial position. The seismic earth pressure distribution shows a half-diamond distribution in the dense sand and a uniform distribution in loose sand. The loading point of dynamic thrust corresponding with seismic earth pressure is at the center of the soil backfill. The dynamic thrust increased differently depending on the backfill's relative density and input motion type. Still, in general, the dynamic thrust increased rapidly when the maximum horizontal displacement of the wall exceeded 0.05 H%.

Earth Albedo perturbations on Low Earth Orbit Cubesats

  • Khalifa, N.S.;Sharaf-Eldin, T.E.
    • International Journal of Aeronautical and Space Sciences
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    • v.14 no.2
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    • pp.193-199
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    • 2013
  • This work investigates the orbital perturbations of the cubesats that lie on LEO due to Earth albedo. The motivation for this paper originated in the investigation of the orbital perturbations for closed- Earth pico-satellites due to the sunlight reflected by the Earth (the albedo). Having assumed that the Sun lies on the equator, the albedo irradiance is calculated using a numerical model in which irradiance depends on the geographical latitude, longitude and altitude of the satellite. However, in the present work the longitude dependency is disregarded. Albedo force and acceleration components are formulated using a detailed model in a geocentric equatorial system in which the Earth is an oblate spheroid. Lagrange planetary equations in its Gaussian form are used to analyze the orbital changes when $e{\neq}0$ and $i{\neq}0$. Based on the Earth's reflectivity data measured by NASA Total Ozone Mapping Spectrometer (TOMS project), the orbital perturbations are calculated for some cubesats. The outcome of the numerical test shows that the albedo force has a significant contribution on the orbital perturbations of the pico-satellite which can affect the satellite life time.

Analyzing Gifted Students' Explanations for Daily Celestial Motion Based on the Earth-based and Heliocentric Frames of Reference

  • Chae, Donghyun;Han, Jejun;Kim, Eunjeong
    • Journal of The Korean Association For Science Education
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    • v.33 no.3
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    • pp.664-678
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    • 2013
  • This study aims to investigate gifted students' explanations for daily celestial motion from the Earth-based and heliocentric frames of reference. Eleven sixth-grade elementary school students were chosen for this study and data was collected through a questionnaire and an in-depth interview. The collected data was analyzed into celestial objects which are the Sun, the moon and the stars and analyzed based on the Earth-based and heliocentric perspectives again. As a result of the research, most gifted students were able to connect the Earth-based and heliocentric frames of reference with the Sun's daily apparent motion. However, they understood the daily apparent motion of the moon and the stars far less frequently compared to the Sun's motion and could not explain the Earth's rotation clearly. The result of the interview showed that the lack of understanding about the daily celestial motion was caused by inaccurate understanding of the Earth's rotation such as using memorized knowledge learned in school and guessing the answer.

Optimal Design of Contour-Lined Plots for Land Consolidation Planning in Sloping Areas (경사지 경지정리지구의 등고선 구획 최적설계)

  • 강민구;박승우;강문성;김상민
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.45 no.6
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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.

A study on the lateral Earth Pressure and Stress Relaxation Region According to the Infinitesimal Deformation of the Wall and Backside Earth Built by Non-excavation Method Under Railroad (철도하부 비개착공법의 벽면배면토사의 미소변형에 따른 수평토압 및 응력이완영역에 관한 연구)

  • Park, Yoon-Sik;Lee, Jun-Seok;Cho, Kook-Hwan
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.2393-2399
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    • 2011
  • In the case where the bottom of railroad is penetrated by non-excavation construction method, the design is performed based on the assumption that there is no displacement and no change of stress However, measurement data showed that reduction of earth pressure and relaxation of stress take place by the displacement. In this study, we investigated the earth pressure on the structure under the railroad constructed by a non-excavation method and the stress relaxation region. The design based on earth pressure is non-economical because it is an over design. Relaxation of stress may lead to road base settlement and rail irregularly due to the reduced railroad supporting stiffness, to ballast crack in the case of concrete roadbed. The result showed that it is reasonable to set the stress on the structures as active earth pressure not as earth pressure at rest. Additionally, the study on the stress relaxation region identified the regions that should be supported in future construction by a non-excavation method.

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The Study on Three-portion and Nine-position Pulse Taking Diagnosis (삼부구후진단(三部九候診斷)에 대한 고찰(考察);"내경"과 "난경"을 중심으로)

  • Eom, Dong-Myung
    • Journal of Korean Medical classics
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    • v.20 no.3
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    • pp.57-65
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    • 2007
  • This present study tried to observe an each feature that the difference of Neijing(內經) and Nanjing(難經) descriptions about the three-portion and nine-position pulse taking(三部九候脈). It was interpreted and contradistinguished that discrimination of position, diagnosis object, and the perceptions of Earth of the center among the Five Phase of each literature were described in Neijing and Nanjing for the three-portion and nine-position(三部九候). In Neijing, the three-portion and nine-position method divided three parts the whole body. Then the each three parts again divided with Heaven, Earth and Man(天地人). About the corresponding parts of pulse diagnosis, there mentioned for the head and the Zang-Fu organs(臟腑), but not mentioned for the hand and foot. In addition, Earth is assigned to the Earth(土), an each Earth accounted for the source of life. In Nanjing, three-portion divided Chon, Gwan, and Cheok(寸關尺) and each spots separated three stage of pulse taking. For the pulse taking spots and diagnosis, there mentioned the hand and foot instead of the unclear mention of Zang-Fu organs. Then Gwan spot and middle stage of pulse taking were assigned to the Earth, respectively. It was emphasized stomach Qi(胃氣) that the region of Earth, Gwan spot and middle stage among the pulse taking spots each literature were described in Neijing, Nanjing.

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A Study on the Variation of the Thermal Load for a House According to the Earth Sheltering Method (복토 주택의 복토 방법에 따른 열부하의 변화에 관한 연구)

  • Lee, Jae-Hyuk;Choi, Won-Ki;Suh, Seung-Jik;Cho, Dong-Woo
    • 한국태양에너지학회:학술대회논문집
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    • 2008.04a
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    • pp.166-171
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    • 2008
  • We cannot imagine any more the environment and energy problems are separated from our lives. The various attempts to solve these problems are made all over the world. In this study it was performed to analyze a different heating and cooling load depending on the earth-sheltering method and kind of soils by using TRNSYS 16 as the first step to establish the design guidelines for earth-sheltered architecture, one of the eco-friendly and low energy consuming building types. After performing this simulation, we found the result like this. It is the most lowest load in case of all of walls and roof being earth-sheltered. But considering of the load reduction rate, the effect of earth-sheltering the exterior vertical wall is more efficient for load reduction than the one of earth-sheltering a roof. And we got a lower thermal load in case of a lower heat conductivity of soil. Afterwards we will conduct a further study for boundary condition at earth-sheltered surface and the simulation analysis about the sensitivity variables. The final goal of this study is preparing the design guidelines for earth-sheltered architecture. so we will contribute to building energy saving.

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3-D Optical Earth System Model Construction and Disk Averaged Spectral Simulation for Habitable Earth-like Exoplanet

  • Ryu, Dong-Ok;Kim, Sug-Whan
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.27.2-27.2
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    • 2011
  • The Kepler(NASA) and CoRoT(ESA) space telescopes are surveying thousands of exoplanet for finding Earth-like exoplanets with similar environments of the Earth. Then the TPF(NASA), DARWIN(ESA) and many large-aperture ground telescopes have plan for spectroscopic observations of these earth-like exoplanets in next decades. Now, it has been started to simulate the disk averaged spectra of the earthlike exoplanets for comparing the observed spectra and suggesting solutions of environment of these planets. Previous research, the simulations are based on radiative transfer method, but these are limited by optical models of Earth system and instruments. We introduce a new simulation method, IRT(Integrated Ray Tracing) to overcome limitations of previous method. The 3 components are defined in IRT; 1)Sun model, 2)Earth system model (Atmosphere, Land and Ocean), 3)Instrument model. The ray tracing in IRT is simulated in composed 3D real scale space from inside the sun model to the detector of instrument. The Sun model has hemisphere structure with Lambertian scattering optical model. Atmosphere is composed of 16 distributed structures and each optical model includes BSDF with using 6SV radiative transfer code. Coastline and 5 kinds of vegetation distribution data are used to land model structure, and its non-Lambertian scattering optical model is defined with the semi-empirical "parametric kernel method" used for MODIS(NASA) and POLDER(CNES) missions. The ocean model includes sea ice cap structure with the monthly sea ice area variation, and sea water optical model which is considering non-lambertian sun-glint scattering. Computation of spectral imaging and radiative transfer performance of Earth system model is tested with hypothetical space instrument in IRT model. Then we calculated the disk averaged spectra of the Earth system model in IRT computation model for 8 cases; 4 viewing orientation cases with full illuminated phase, and 4 illuminated phase cases in a viewing orientation. Finally the DAS results are compared with previous researching results of radiative transfer method.

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