• Tunnel and Underground Space
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• v.22 no.2
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• pp.106-119
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• 2012

Roughness of rock joint has generally been characterized based upon geometrical aspects of a two-dimensional surface profile. The appropriate description of joint roughness, however, should consider the features of roughness mobilization at contact areas under normal and shear loads. In this study, direct shear tests were conducted on the replicas of tensile fractured gneiss joints and the influence of the shear direction on the shear behavior and effective roughness was examined. In this procedure, a joint surface was represented as a group of triangular planes, and the steepness of each plane was characterized using the concepts of the active and inactive micro-slope angles. The contact areas at peak strength which were estimated by a numerical method showed that the locations of the contact areas were mainly dependent on the distribution of the micro-slope angle and the shear behavior of joint was dominated by only the fractions with active micro-slope angles. Therefore, a three-dimensional coefficient for the quantification of rock joint roughness is proposed based on the distribution of active micro-slope angle: active roughness coefficient, $C_r$. Comparison of the active roughness coefficient and the peak shear strength obtained from the experiment suggests that the active roughness coefficient is the effective parameter to quantify the surface roughness and estimate the shear behavior of rock joint.

• Korean Journal of Optics and Photonics
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• v.35 no.5
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• pp.199-209
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• 2024

Predicting the performance of adaptive optics systems is a crucial step in their design and analysis. First-order prediction methods, based primarily on several assumptions and scaling laws, are commonly used. These methods must account for various parameters and error sources, such as the intensity and profile of atmospheric turbulence, fitting errors based on the resolution of the wavefront sensor and deformable mirror, wavefront-sensor noise propagated through the wavefront-reconstruction algorithm, servo lag due to the finite bandwidth of the control loop, and anisoplanatism caused by the arrangement of natural and laser guide stars. However, since first-order performance-prediction methods based on certain assumptions can sometimes yield results that deviate from real-world performance, evaluation through computational simulations and closed-loop tests on a testbed is necessary. Additionally, an atmospheric simulator is required for closed-loop testing, which must adequately simulate the spatial and temporal characteristics of atmospheric disturbances. This paper aims to present an overview of the theory of atmospheric disturbance simulators, as well as their implementation in computational simulation and hardware.

• Anatomy & Biological Anthropology
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• v.31 no.4
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• pp.133-142
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• 2018

3D histology is a imaging system for the 3D structural information of cells or tissues. The synchrotron radiation propagation phase contrast micro-CT has been used in 3D imaging methods. However, the simple phase contrast micro-CT did not give sufficient micro-structural information when the specimen contains soft elements, as is the case with many biomedical tissue samples. The purpose of this study is to develop a new technique to enhance the phase contrast effect for soft tissue imaging. Experiments were performed at the imaging beam lines of Pohang Accelerator Laboratory (PAL). The biomedical tissue samples under frozen state was mounted on a computer-controlled precision stage and rotated in $0.18^{\circ}$ increments through $180^{\circ}$. An X-ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens(X5 or X20) before being captured with a digital CCD camera. 3-dimensional volume images of the specimen were obtained by applying a filtered back-projection algorithm to the projection images using a software package OCTOPUS. Surface reconstruction and volume segmentation and rendering were performed were performed using Amira software. In this study, We found that synchrotron phase contrast imaging of frozen tissue samples has higher contrast power for soft tissue than that of non-frozen samples. In conclusion, synchrotron radiation propagation phase contrast cryo-microCT imaging offers a promising tool for non-destructive high resolution 3D histology.

• (The)Study of the Eastern Classic
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• no.73
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• pp.185-217
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• 2018

This research is a part of basic research on Gyeonggi Kamyoung focused on reconstruct personnel organization and facility of Gyeonggi Kamyoung, the only Kamyoung without a Kamyoung Record, which should have been recorded on it. Excluding Gyeonggi Kamyoung, other 7 Kamyoung each have its Kamyoung Record that shows their detailed history and set up. Due to lack of information about Gyeonggi Kamyoung, this research set objective on reconstructing Kamyoung Record of it with fragments of information on multiple historical records. By doing this, this research will also be a background for general research on distinguishing administrative unity from regional uniqueness of all 8 provinces Kamyoung. Kamyoung's personnel organization is sorted into government official from central government and Yeongli and staff. The information about the government official on this research is based on "Ki-Yung-Jang-Gae- Deung-Rok"'s personal assessment. According to it, Dosa Junggun Geomlyul had the same task and position as others in different provinces did. The difference Gyeonggi Kamyoung had was an absence of Sim Yak since 1700 while others still had it. The information about Yeongli and staff's organization was based on "Ki-Yeong-Sin-Jeong-Sa-Le". In Gyeonggi Kamyoung, along 6-Bang, there were 208 Yeongli and staff categorized into 50 different official duties. Also, compared to other Kamyoungs, Youngli's scale was smaller. Kamyoung's facility inside Pojeongmun and wall is distinguished from other Kamyoung related facilities in this research. Organization of facilities inside Pojeongmun and wall is based on "Gyeonggi-Kamyoung-Do". Like other Kamyoungs in different provinces, Seonhwadang, which is the main building, is located in the center and had a similar organization. Significant point was that Gyeonggi Kamyoung had both Youngli-Cheong and Hyeongli-Cheong at the same time. In the dense and developed area outside of Seodaemun, Gyeonggi Kamyoung had its related facility around it in small scale.

• Cartoon and Animation Studies
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• s.49
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• pp.359-382
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• 2017

Content is the complex of art and technology of trend, so it is important to experience different technologies for content education. Today, many non-profit organizations plan and operate numbers of programs for disabilities, low-income, and minority families to enhance the quality of life and the realization of social integration. These programs are limited to museums and galleries, not so pro-actively in progressing. Various contend education is necessary to the expansion of cultural exchange for the culturally alienated area. Naver is running an outreach program named . It is an experience-based outreach program where current cartoon / webtoon writers come directly to the school to inform students about the basic story of comics and comic techniques. However, the fact that the is not centered on the marginalized area but is centered on the Seoul Gyeonggi area, has the limitation that they can not benefit from a wide range of programs because they have a space limit of 'school', and, has a spatial limitation that the experience of the work is excluded. 'Outreach programs in marginalized areas' must be reorganized into a fluid dimension, not a fixed, single-system program. You should be able to experience and experience your work by directly using various professional equipment of comics based on your capacity and experience, local culture, religion, and society. These program participants will gain the effect of attractive and effective learning with empathy with their comic experience. Meanings of Comics content outreach program are following: First, the rich cultural archive can be used efficiently by providing various contents to existing outreach programs with the educational limitation of museums and galleries. Second, Comics contents can be enjoyed as a part of our life by understanding diversity and technology of contents. Third, because it is the program of expertise' participation, it can remodel, and restructure the severed experience in remote areas for the continuous growth and development, and furthermore, it can enhance the understanding of society.

• The Korean Journal of Nuclear Medicine
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• v.39 no.6
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• pp.413-420
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• 2005

Purpose: Neuroreceptor PET studies require 60-120 minutes to complete and head motion of the subject during the PET scan increases the uncertainty in measured activity. In this study, we investigated the effects of the data-driven head mutton correction on the evaluation of endogenous dopamine release (DAR) in the striatum during the motor task which might have caused significant head motion artifact. Materials and Methods: $[^{11}C]raclopride$ PET scans on 4 normal volunteers acquired with bolus plus constant infusion protocol were retrospectively analyzed. Following the 50 min resting period, the participants played a video game with a monetary reward for 40 min. Dynamic frames acquired during the equilibrium condition (pre-task: 30-50 min, task: 70-90 min, post-task: 110-120 min) were realigned to the first frame in pre-task condition. Intra-condition registrations between the frames were performed, and average image for each condition was created and registered to the pre-task image (inter-condition registration). Pre-task PET image was then co-registered to own MRI of each participant and transformation parameters were reapplied to the others. Volumes of interest (VOI) for dorsal putamen (PU) and caudate (CA), ventral striatum (VS), and cerebellum were defined on the MRI. Binding potential (BP) was measured and DAR was calculated as the percent change of BP during and after the task. SPM analyses on the BP parametric images were also performed to explore the regional difference in the effects of head motion on BP and DAR estimation. Results: Changes in position and orientation of the striatum during the PET scans were observed before the head motion correction. BP values at pre-task condition were not changed significantly after the intra-condition registration. However, the BP values during and after the task and DAR were significantly changed after the correction. SPM analysis also showed that the extent and significance of the BP differences were significantly changed by the head motion correction and such changes were prominent in periphery of the striatum. Conclusion: The results suggest that misalignment of MRI-based VOI and the striatum in PET images and incorrect DAR estimation due to the head motion during the PET activation study were significant, but could be remedied by the data-driven head motion correction.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.88-99
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• 2012

This study was to analyze the changes made in the landscape cognition in Yong-in City for the past 10 years. For the analysis, the landscape plan in 2001, and the survey data collected for the new 2012-landscape plan were used. The questions on the survey covered the cognition of the current landscape status, the evaluation of landscape depending on the types of landscape, the understanding of each element on the landscape, the residents' cognition, etc. In the evaluation of the status on current landscape, Everland was ranked outstandingly high as a symbol and a representative place both in 2001 and 2012. The image of the overall city landscape was changed from the image of unique, diverse, grand-scale and well ordered in 2001, to the image of wide, disordered, common and realistic. As the evaluation of individual landscape types such as the view of the mountain, the surroundings of the tourist attractions, colors, etc, has improved overall. The image of the city has been evaluated to improve gradually, especially in the level of individual element. In the study of participating the willingness of residents, despite the interest in landscape has been continued, the attitude for the actual participation in the action plan or the restriction of property right has been changed into a negative side. For the direction of the landscape plan, the residents are more interested in the detailed subjects : such as the financial support, the night landscape plan, the improvement of the problems, etc. During the last 10 years, the changes on the landscape cognition in Yong-in City have changed more in detail and specifically, the cognitions on the local government and developers changed positively. However the reducion of the participants' willingness suggested a review on the policies and the projects of the landscape.