• Journal of the Korean Institute of Gas
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• v.8 no.2 s.23
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• pp.35-41
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• 2004

This paper presents the stress and deformation characteristics of $9\%$ nickel based inner tank bottom plate in full containment LNG storage tank. When a . maximum hydrostatic pressure applies the bottom plate of inner tank, the maximum = f stress and displacement distributions of the bottom plate have been analyzed as ' functions of inclined angle of the bottom plate, and the thickness and length of the annular plate between the shell plate and bottom one. The calculated results indicate that the taper of the bottom plate is recommended by 100${\~}$200 : 1 for $140,000m^3$ storage capacity of the inner tank. The results recommend that the thickness of the annular plate is around 20mm and the length is greater than 3m for a maximum hydrostatic pressure of $140,000m^3$ tank capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3894-3906
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• 2014

The aim of this study was to classify the central Buddhist temple among the state-designated cultural assets, which were measured precisely, into the gable roof buildings and the gambrel roof buildings to analyze the Ang-Goak, Inside waist, ridge ratio, and roof inclination represented on the roof, and prepare basic objective material for the restoration and repair of cultural assets. As a result, as for the relationship between the roof curve and the inclination of the gable roof building and gambrel roof building, the following conclusions could be drawn. First, the Ang-Goak and Inside waist of the gable roof building had a close correlation with the building size, and the internal high pillar existence. In addition, the Ang-Goak and Inside waist were shown in the 7-ryangga structure, which is greater in size than in the 5-ryangga structure. This was found to be related to the building size. Second, the Ang-Goak and Inside waist of the gable roof building has a correlation with each other, and it was found that Inside waist also was large in the building with a larger Ang-Goak. The roof inclination rarely had a connection with variable factors (plane factor, elevation factor, and cross section factor). The sizes of Ang-Goak, Inside waist, and ridge ratio were similar in the outside 1 chulmok and outside 2 chulmok of gongpo but those sizes were relatively larger in outside 3 chulmok. Third, the Ang-Goak and Inside waist of the gambrel roof building moved independently for each building without a correlation with each other, unlike the case of the gable roof building. The front and the side showed a correlation with each other, and in the building with the large curve of the front side, the curve was also large in the sides. Fourth, in the case of the building with a high pillar inside the gambrel roof building, the Ang-Goak and Inside waist were larger. On the other hand, they were smaller in the case of a building without a high pillar. This was found to have a close relationship with the building size. In addition, the ridge ratio has a close connection with the building size and building height. Therefore, the ridge ratio is larger in a high building or large sized building. The roof inclination rarely has a correlation with variable factors, as in the case of the gable roof building.

• Journal of Digital Contents Society
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• v.4 no.2
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• pp.211-221
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• 2003

The objective of this paper is performance analysis of the digital document image decimation algorithm which generates a value of decimated element by an average of a target pixel value and a value of neighbor intelligible element to adaptively reflect the merits of ZOD method and FOD method on the decimated image. First, a target pixel located at the center of sliding window is selected, then the gradient amplitudes of its right neighbor pixel and its lower neighbor pixel are calculated using first order derivative operator respectively. Secondly, each gradient amplitude is divided by the summation result of two gradient amplitudes to generate each local intelligible weight. Next, a value of neighbor intelligible element is obtained by adding a value of the right neighbor pixel times its local intelligible weight to a value of the lower neighbor pixel times its intelligible weight. The decimated image can be acquired by applying the process repetitively to all pixels in input image which generates the value of decimated element by calculating the average of the target pixel value and the value of neighbor intelligible element. In this paper, the performance comparison of proposed method and conventional methods in terms of subjective performance and hardware complexity is analyzed and the preferable approach for developing the decimation algorithm of the digital document image on the basis of this analysis result has been reviewed.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.1
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• pp.41-47
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• 2010

Purpose: To compare the obliquity of femoral tunnels prepared with transtibial (TT) versus anteromedial portal technique (AM) using x-ray in single-bundle anterior cruciate ligament (ACL) reconstruction. Materials and Methods: Among one-hundred thirty two patients who were undergoing ACL reconstruction from January 2007 to December 2009, thirty patients using TT and twenty patients using AM, those who had single-bundle ACL reconstruction, were evaluated with plain radiographs including anteroposterior, intercondylar notch and lateral view to compare the obliquity of bone tunnels. Results: The mean coronal obliquity of femoral tunnel for TT was $71^{\circ}$ (range; $65^{\circ}{\sim}77^{\circ}$), while for AM was $51^{\circ}$ (range; $39^{\circ}{\sim}60^{\circ}$) and the mean sagittal obliquity of femoral tunnel for TT was $22.7^{\circ}{\pm}7.8$, while for AM was $30.2^{\circ}{\pm}6.9$, their differences between them were statistically significant (P<0.05). However, there were no differences between two techniques on the tibial tunnel obliquity in coronal and sagittal plane. Conclusion: Anterior cruciate ligament reconstruction using AM portal technique allows more horizontally oriented and divergent femoral tunnel compared to that of transtibial technique. This seems to enable the graft placement into the femoral footprint and preserve the posterior cortical wall.

• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.1-9
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• 2020

This study analyzes contaminant movement under transient flow in a rubble mound revetment offshore waste landfill barrier system that prevents contaminant runoff. The barrier system consists of bottom layer and side barrier. For the bottom layer system, impermeable clay layer is used. For the side barrier system, the HDPE barrier sheet (primary element) plays the main role, and the intermediate protection layer (supplementary element) is responsible for the barrier. Seepage, advection, dispersion numerical analysis was carried out using SEEP / W and CTRAN / W programs. As a result, under abnormal conditions considering the fluctuation in tidal range, the volume and direction of the flow velocity vector of the pore water change with time and the dispersion concentration of the contaminant changes. When comparing the case of 2 m tidal range and 8 m tidal range, the larger the tide value, the higher the concentration of contaminant under abnormal conditions. It was found that the rate of change of the concentration of the contaminant changed depending on the change in the tidal range, and as a result, the outflow of the pollutant was smaller than that in the steady flow state.

• Korean Journal of Optics and Photonics
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• v.11 no.6
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• pp.434-440
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• 2000

We fabricated a high power Nd:YAG laser pumped by a 1 kW diode laser with a Lambertian-type diffusive reflector. Maximum cw power of 500 W with a slope efficiency of 49%, which corresponds to an optical efficiency of 46.7%, was obtained from a short linear resonator when a 5 mm rod was used. The efficiencies decreased when a 6 mm rod was used, due to the poor quality of the absorption distribution in the rod. The measured beam quality factor of 70, which is slightly smaller than the value calculated from the measured thermal focal lengths, shows that the absorption distribution in the rod is fairly uniform. iform.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.2
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• pp.159-166
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• 1996

It has the imfortant significance to study of 3 dimensional precision surveying and analysis system for conservation of culutral properties. This study is about to efficient precision surveying methods and analysis of digital information data for conservation of cultral properties. We acquire the photos and construct the 3 dimensional digital information in 1 n accuracy, and carry the spatial analysis to five story pagoda at Chongrimsa temple site of National Treasure No. 9 of Korea. In result, we carry the 3 dimensional modelling accurately and the efficient geometrical analysis of sections, calculation of the aera, volumn, and position and slope of con-trial axis. So, we expect efficient use of as well study of art history as safety diagonise for the preservation of cultural properties.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.1
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• pp.45-54
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• 2012

Optimization of the asymmetric trapezoidal fin with various upper lateral surface slope is made using a two-dimensional analytic method. For the fixed fin base height, the optimum heat loss, fin length and effectiveness are represented as inner fluid convection characteristic number, fin base thickness, fin base height, fin shape factor and ambient convection characteristic number. For this optimum procedure, the optimum heat loss is defined as 95% of the maximum heat loss from the fin. One of the results shows that optimum heat loss and effectiveness seems independent of the fin shape factor while optimum fin length decreases almost linearly as the fin shape factor increases.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.2
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• pp.136-143
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• 2013

In this paper, a monitoring system for telecommunication tower using wireless sensor network is presented. Although safety inspection could be judged by eyesight and calculating original design from now, not only this system can protect perils, estimating data exactly, but also it is effective to management. It is also economic because the system costs cheaper expenses for telecommunication tower of setting it once than for the tower of inspecting its safety regularly. This paper proves that the structure can be managed scientifically and efficiently, and the system contributes not only stabilized telecommunication services for users but reducing damages.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1137-1139
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• 1999

저가의 우수한 성능을 갖는 적외선 영상표시 소자 구현에 적합한 마이크로 볼로미터를 MEMS 기술을 사용하여 제작하였다. 작은 열질량을 갖는 마이크로미터 단위의 열적고립 구조(thermal isolation structure) 제작은 폴리이미드(PI2611)를 희생층으로 사용하여 최종적으로 ashing공정 단계에서 폴리이미드를 제거하여 마이크로 볼로미터 구조를 완성하였다. 이 때의 구조층으로는 PECVD 질화실리콘($SiN_x$) 박막, 감지층으로 산화바나듐($VO_x$) 박막을 사용하였다. 본 연구에서는 폴리이미드 패턴 형성시 건식식각 공정조건 변수에 따라서 패턴의 기울기를 조절하여 폴리이미드 측면에서 발생되는 불 균일한 박막 증착과 패터닝 문제를 개선하였다. 또한 저응력의 질화실리콘 박막을 사용하여 잔류응력에 의한 열적고립 구조의 뒤틀림 현상을 완화하였다.