• Tunnel and Underground Space
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• v.1 no.2
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• pp.218-228
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• 1991

Natural stress measurements have been made at two sites at the depth of 280m from surface by means of stress relief overcoring methods using three directonal deformation gage. Attempts have been made to determine the state of natural stress in the rock and provide useful basic data to investigate the stress distribution and the determination of yield zone around powerhouse cavern. The magnitude and the direction of the miximum principal stress obstained from in-situ stress measurements is -96.1kgf/$\textrm{cm}^2$ and N38$^{\circ}$W, N35$^{\circ}$W respectively. Vertical stresses are in approximately agreement with the theoretical value. The ratio of measured to theoretical stresses are 85% at two sites. The ratio of average horizontal to vertical stresses(k=($\sigma$h)ave/$\sigma$v is 1.07.

• The Journal of the Korean dental association
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• v.54 no.12
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• pp.996-1023
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• 2016

There are many kinds of maintenance care services for removable denture patient. Adjustment of the denture base and occlusion should be performed regularly not only for pain relief but also for maintaining the denture function. Direct and indirect relining are needed frequently in specific cases including mandibular distal extension case or non-symmetric residual teeth situation. Surface treatments for metal and resin are essential in the relining procedure. Clinical process for the denture repair is similar to indirect relining which needs inter-occlusal registration. Especially, the peridontal maintenance care and caries prevention are most important way to preserve the abutment teeth in partial edentulism. Moreover, the caring method for the denture and the tissue should be instructed to the denture patient.

• The Journal of Engineering Geology
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• v.3 no.1
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• pp.75-81
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• 1993

Four tecbniques are treated. The technique using the area and the perimeter is very easy but considerable error can be made and commonly the technique using grid is used. Particularly, simaar technique using computer makes possible to represent the slope at each point of the grid and to compare with other data. The tehcnnique using vector product, with which a cuuved surface can be measured directly by segmenting by triangles, is useful but it represent considerable error where the relief is rugged.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.2
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• pp.117-125
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• 2004

This paper describes the orthometric correction for determining the orthometric height obtained from height difference by precise leveling or GPS leveling. Five formulas are used to calculate the orthometric correction for two level lines as an examples. Based on the comparison results Strang van Hees' formula that use the surface gravity is better than the others to compute the orthometric corrections on spirit leveling and GPS/Leveling in an area where mean hight is high and terrain relief show high variability. Further research is necessary to improve the results of this study using Mader method, etc..

• Journal of Information Display
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• v.9 no.1
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• pp.14-19
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• 2008

We demonstrated the capillary force lithography (CFL) method for controlling the azimuthal anchoring energy of a liquid crystal (LC) alignment layer. When a thermoplastic polymer film is heated to over the glass transition temperature, the melted polymer is filled into the mold structure by the capillary action and the aspect ratio of the pattern is determined by the dewetting time of the CFL process. Here, the proposed method showed that the azimuthal anchoring energy of the LC alignment layer could be simply controlled by the surface relief patterns which were determined by the dewetting times during the CFL patterning.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.248-249
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• 2003

아조벤젠 고분자는 광 정보저장 및 광 스위치 소자 등의 응용가능성 때문에 많은 연구가 진행되어왔다. 이것은 바로 아조 분자가 가지고 있는 두 이성체 간의 광 이성화 과정에 의한 아조 분자의 정렬과 이 때문에 야기되는 광 유도 anisotropy가 생기는 특성 때문이다. 이와 더불에 아조 분자 필름에 빛을 쪼여 주었을 때 표면에 주기적인 부조 격자(SRG)가 형성됨이 보고 된 이후에 광 정보 저장은 물론 액정의 anchoring 이나 phase mask로의 응용, 특히 photonic band gap(PBG) 효과를 기대 할 수 있는 주기구조 형성에의 응용성 때문에 더욱 관심이 집중되고 있다. (중략)

• Journal of the Speleological Society of Korea
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• no.69
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• pp.49-60
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• 2005

This Study is about the wetlands in the GyunggiDo Mountains. It is written in the point of the hydrogeomorphology, geology, and soil. And it has accessed to ecological environment. Wetlands are divided into mountain wetlands and river wetlands by location, relief, processes, hydrology, and the type of inlet and outlet of water in wetlands. Mostly mountain wetlands are formed by the process of destruction of mountain slope. So they are to be located in the knickpoint. Therefore the underground surface is visible and underground water is rising or leaking. At this process, the environment forming wetlands are made by soil that was influenced by geology and composed by fine and very fine granules.

• Korean Journal of Optics and Photonics
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• v.4 no.4
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• pp.390-396
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• 1993

When a one-dimensional telecentric paraxial holographic kinoform is used as a Fourier transform lens, we analyzed three surface-relief structures, i.e., plano-convex, convex-plano and biconvex shapes, employing exact raytracing method based on Snell's law. For the kinoform of E/8 and focal length of 15 mm, the number of zones, the thickness, and the slope of parabolic surfaces are varied by changing the refractive indicies of kinoform material and surrounding medium. It is found that biconvex shape gives the best results in general, although off-axis performance degrades in all cases as the slope of parabolic surfaces increases.

• Journal of the Optical Society of Korea
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• v.12 no.3
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• pp.205-209
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• 2008

We demonstrated a simple way of evaluating the duty cycle error in periodically polled lithium niobate(PPLN) based on the method of binary phase diffraction grating. To demonstrate this method, -Z face etched PPLN of desired periods were fabricated by the standard electric field poling technique. The etched PPLN was considered as a surface-relief binary phase grating. The diffraction patterns were recorded for different spatial locations along the length of the sample. The experimentally observed efficiencies of the diffracted orders were compared with the theoretically calculated values to estimate the duty cycle error.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.109-112
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• 2007

A new concept of the microlens array is fabricated using a birefringent layer on the concave microlens array. The stacked layers of liquid crystalline polymer (LCP) and the UV epoxy focus an incident light due to the surface relief structure. The ferroelectric liquid crystal layer was added to control the focusing intensity with a fast switching time.