• 건축역사연구
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• 제27권5호
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• pp.7-16
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• 2018

This study investigated the dimensional plan of Kor Sork temple in Preah Pithu complex, Angkor by civil surveying, 3D scan, measured integer ratio and regularity. According to epitaph and preceding researches, Khmer temples were built based on structural planing with the constant ratio and regularity by using special construct measure scales "Hasta" and "Byama". The study assumed the same unit method was applied in Kor Sork temple and identified the regularity of actual measurement value about the temple. The assumed construct measure scale (Hasta) used for the design of this temple is 413mm. The overall apart arrangement of the temple is different in the East-West direction and the North-South direction. In the East-West direction, the whole scale is 180 hasta, and it is divided into 20 hastas. On the other hands, it was confirmed that the North-South direction is 96 hasta and it was divided four quadrants in 24 hastas. Regarding the detailed design, the regularity according to the constant ratio was confirmed. 7 hasta was used as the basic unit on the first floor and 6 hasta were used as the basic unit on the second floor of the terrace. the basement and the central sanctuary is of 6 hasta and 8 hasta were used as the basic standard.

• 한국결정성장학회지
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• 제4권4호
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• pp.388-394
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• 1994

단결정 Hg(1-x)Cd(x)Te (MCT,X=0,21)가 특수 제작된 고압로에서 Traveling Heater Method(THM)으로 성장되었다.X-선 회절 실험으로 MCT는 입방ZnS 구조임을 확인하였다. 측정된 격자상수는 $6.464 {\AA}$이엇으며, J.C.Wooley가 측정한 값과 비교하여 얻은 MCT의 성분비는 0.21이었다.MCT의 결정 구조를 분석하기 위하여 X-선 회절 강도로 부터 전자 밀도를 계산하였다.전자 분포 밀도도로 부터 MCT는 주로 공유 결합을 하고 있으며, 인접 원자들 상에는 사면체 구조를 이루고 있음을 알 수 있다. 격자 상수가 Vegard line으로 부터 편이 되는 원인은 성분비x가 증가될 때 원자간 거리 변화의 비선형적 증가로 판단되며, 이것은 결합 에너지와 관련될 것으로 추축된다.

• 한국제4기학회지
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• 제19권2호
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• pp.50-54
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• 2005

Some basic summer precipitation features over East Asia during the $20^{th}-21^{st}$ century as simulated / projected by the 22 coupled climate models under the IPCC AR4 program are investigated. Keeping in view that these are climate runs without prescribed SSTs, models perform well in simulating the regional annual cycle, spatial patterns (not shown) and the inter-annual variability. The projections under the 1% increase in $CO_2$ compounded until reaching double and held constant thereafter reveal that (a) Precipitation is likely to increase in all the months in particular during the summer monsoon (JJA) months. (b) The mean summer monsoon rainfall can increase from 4.2 to 13.5% and its variability is also likely to increase in the warming world due to increase in $CO_2$ (c) Extreme excess and deficient seasonal monsoons are likely to become more intense (not shown here) (d) Once the increase in $CO_2$ is cut-off, the system will reach a state of equilibrium, and then the rate of increase in precipitation is also expected to remain constant.

• 물과 미래
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• 제29권5호
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• pp.235-244
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• 1996

호수에서의 수직온도분포를 모의하기 위하여, 수리학적 특성 즉 유속분포가 필요없는 일차원 와확산모델 및 혼합층모델이 개발, 적용되었으며 각 모델의 결과가 비교, 검토되었다. 전자는 지배방정식 유도시 분자확산을 모델적용시 년간 수면변화를 무시했으며, 후자는 간단한 해석을 위하여 일정한 층의 두께를 가정하였다. 호수표면과 바닥에서의 온도경계조건이 각각 열 에너지의 이동에 의해서 결정되도록 하는 와확산모델은 explicit 유한차분법을, 두층을 이용하는 혼합층모델은 Runge-Kutta 방법을 사용하였다. 측정된 데이타와 와확산모델 및 혼합층모델의 계산치와 비교해본 결과, 만족한 결과를 도출하였다. 따라서, 호수관리의 수단으로 이 모델들을 유용하게 이용할 수 있을 것으로 사료된다.

• 한국결정성장학회지
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• 제5권4호
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• pp.394-399
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• 1995

산소 팔면체의 tilting에 의한 초격자 구조를 하고 있는 $(Na_{0.5}Sr_{0.5})(Ti_{0.5}Nb_{0.5})O_{3}$의 온도 변화에 다른 유전 특성 및 X-선 회절에 의한 구조의 변화를 살펴보았다. 유전 손실 측정에서 관측되는 380 K 부근의 peak는 primitive cell이 정방정에서 입방정으로 변화함에 따라 생기는 peak임을 알 수 있었으며 이 때 유전율의 변화는 관측되지 않았다. 따라서 유전 손실이 재료 내의 구조적 변화를 인지하는데 유전율보다 민감하다는 것을 알 수 있었다. Primitive cell 이 입방정으로 변화한 후에도 산소 팔면체의 tilting에 의한 초격자 회절선은 여전히 관측되었으며 500 K 정도에서 완전히 사라짐을 알 수 있었다. 하지만 이때 유전 특성의 변화는 관측되지 않았다.

• 대한치과교정학회지
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• 제22권1호
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• pp.135-146
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• 1992

It was the purpose of this study to analyze and compare the mechanical properties of ortho dontic open coil springs. Four variable factors were presented - wire diameter (.008", .009", .010"), lumen size (.030", .032", .036"), arch wire size and shape (.016" round, $ .016^{{\prime}{\prime}}{\times}.022^{{\prime}{\prime}}$ rect.) and alloy type (HiT II, Elgiloy, Sentalloy). The total 104 specimens were divided into 13 groups, and compression test was performed on an Instron test machine. The load deflection curve of each open coil spring was obtained, from which, the load-deflection relations, stiffnesses, percent recoveries were computed statistically. The results were obtained as follows: 1. When the lumen size of the coil spring remained constant, stiffness and percent recovery increased as the wire diameter increased. 2. When the wire diameter of the coil spring remained constant, stiffness and percent recovery decreased as the lumen size increased. 3. The effect of size and shape of arch wire on the coil spring was not statistically significant. 4. In alloy types, stiffness was the greatest in HiT II (55.21), Elgiloy (42.61) and Sentalloy (7.74) in that order. Sentalloy exhibited superior percent recovery and long range of action.

• 물과 미래
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• 제10권1호
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• pp.20-24
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• 1977

43,000 shallow water wells have been installed as a part of all weather irrigation water supply project executed during 1969 to 1970 in all over Korea penninsula in order to solve water shortage problem of farming land by developing shallow ground water reserved in unconsolidated materials. But after 3 years later it was reported that 34% of the wells were abandoned by the reasons of artificial and natural defects. 48 wells distributed uniformly in the penninsula are selected to determine their well loss constants, relation between well loss and specific capacity, and tophographic classification of the well loss on the shallow water well. The results show that average well loss consatnt and the value of $CQ^2/S_w$ is ranged from $5.95{\times}10^{-5}\;to\;3.65{\times}10^{-8}Day^2M^{-5}$ and from 35.5% to maximum 68.48% respectvely and that relation between specific capacity and well loss constant can be approximately formulated as $C=0.61S_p2.246$ However this result indicates that most wells installed in this time have too high value of well loss constant $CQ^2/S_w$ in comparison with properly deseigned well. The most favorable and producable water bearing formation among unconsolidated deposits such as sand & gravel, boulderly gravel, clayey boulderly gravel, and sand formation in Korea is sand formation deposited in center of valley.

• 분석과학
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• 제9권4호
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• pp.411-415
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• 1996

The new potentially heptadentate $N_7$ ligand 1, 15-bis(2-pyridyl)-2, 5, 8, 11, 14-pentaazapentadecane(pytetren) has been synthesized and characterized by EA, IR, NMR, and mass spectrometry. Its proton association constants (log $K{_H}^n$) and stability constants(log $K_{ML}$) for $Co^{2+}$, $Ni^{2+}$, $Cu^{2+}$, and $Zn^{2+}$ ions were determined at 298.1K and ionic strength=0.100M($KNO_3$) by potentiometry: log $K{_H}^1=9.36$, log $K{_H}^2=9.12$, log $K{_H}^3=8.09$, log $K{_H}^4=6.62$, log $K{_H}^5=4.02$, log $K{_H}^6=2.54$: log $K_{ML}(CO^{2+})=22.67$, log $K_{ML}(Ni^{2+})=26.25$. log $K_{ML}(Cu^{2+})=28.46$, log $K_{ML}(Zn^{2+})=19.90$.

• PNF and Movement
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• 제5권1호
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• pp.49-56
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• 2007

Objectives : We find that the reaction force on the elbow joint during elbow flexion, extension with and without an object in the hand can be calculated the equations of motion that the sum of the torque and the sum of the force acting on the elbow joint must be zero and (moment of inertia x angular acceleration) and (mass x acceleration). Methods : we have calculated the equations of motion (${\Sigma}F=0$, ${\Sigma}{\tau}=0$, ${\Sigma}F=ma$, ${\Sigma}{\tau}=Ia$) to investigate the reaction force on the elbow joint during elbow flexion, extension by means of the simplified free-body technique for coplanar forces. Results : we found that the reaction force on the elbow joint during elbow flexion, extention as constant acceleration motion is more than constant velocity, static motion. Also, we found that the relation between during flexion and during extension like this ; $J_{flexion}$ < $J_{extension}$.

• 물과 미래
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• 제29권4호
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• pp.177-186
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• 1996

하천 만곡부에서의 하상 횡경사 결정은 유수와 유수의 소류력에 의해 변동하는 하상면과의 상호관계를 규명하는 이론적인 접근에서 출발하게 된다. 이러한 경우 흐름은 완전히 발달한 흐름으로 해석하게 되며 하상에서는 소류사가 일어나고 있는 상태에서 유수력과 하상물질에 의한 저항력간의 평형을 바탕으로 해석을 시도하게 된다. 한계소류력을 대표하는 연구로서 Shields diagram이 많이 이용되고 시동조건으로 Shields parameter를 0.06으로 대표해 주고 있다. 지금까지 만곡부의 하상횡경사 결정에서는 대부분의 방법들이 Shields parameter 의 적용에서 0.06을 일률적으로 채택하고 있다. 본 연구에서는 Shields parameter에서의 실험조건인 균일입경하상이라는 조건이 적용되지 않는 일반 자연하천에서 혼합입경하상의 입도분포곡선 형태에 따라 생기는 Shields parameter의 변동을 고려할 수 있도록 하므로써 보다 정확한 만곡부 하상횡경사 추정이 가능한 방법을 제시하였다.