• Korean Journal of Remote Sensing
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• v.8 no.2
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• pp.131-145
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• 1992

A low cost personal computer and image processing S/W were empolyed to derive Digtal Elevation Model(DEM) of tidal flat from multitemporal LANDSAT TM images, and to create three-dimensional(3D) perspective views of the tidel flat on Komso bay in west coasts of Korea. The method for generation of Digital Elevation Model(DEM) in tidal flat was considered by overlapping techniques of multitemporal LANDSAT TM images and interpolations. The boundary maps of tidal flat extracted from multitemporal images with different water high were digitally combined in x, y, z space with tide in formation and used as an inputcontour data to obtain an elevation model by interpolation using spline function. Elevation errors of less than $\pm$0.1m were achived using overlapping techniques and a spline interpolation approach, respectively. The derived DEM allows for the generation of a perspective grid and drape on the satellite image values to create a realistic terrain visualization model so that the tidal flat may be viewed from and desired direction. As the result of this study, we obtained elevation model of tidal flats which contribute to characterize of topography and monitoring of morphological evolution of tidal flats. Moreover, the modal generated here can be used for simulation of innudation according to tide and support other studies as a supplementary data set.

• The Journal of Korean Physical Therapy
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• v.31 no.5
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• pp.328-332
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• 2019

Purpose: This study examined the effects of transcranial direct current stimulation (tDCS) on the static balance ability of patients with back pain. Methods: The subjects comprised of 30 males and females in their 20s, who were divided into two groups with and without tDCS. The balance posture ratio score was calculated to determine the changes in balance ability before and after the application of tDCS using balance equipment. A paired t-test was conducted to determine the changes over time, and an independent t-test was performed to determine the changes between the groups. The significance level was set to ${\alpha}=0.05$. Results: A significant difference in the changes in the static balance ability of CTDCSG between before and after applying tDCS was observed while the subjects' eyes were open (p<0.05). A comparison between the groups after the experiments revealed significantly increased changes in CTDCSG compared to STDCSE (p<0.05). The changes in static balance ability were not significant when the subjects' eyes were closed (p>0.05). Conclusion: The application of tDCS positively changed the static balance ability of patients with back pain. The results of this study showed that tDCS could be used as an intervention to increase the static balance ability of patients with back pain in the clinical field. The study results could be used further as foundational data for future studies on tDCS.

• The Journal of Advanced Prosthodontics
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• v.13 no.4
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• pp.216-225
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• 2021

PURPOSE. The aim of this study is to evaluate the effects of canine guidance occlusion and group function occlusion on the degree of stress to the bone, implants, abutments, and crowns using finite element analysis (FEA). MATERIALS AND METHODS. This study included the implant-prosthesis system of a three-unit bridge made of monolithic zirconia and hybrid abutments. Three-dimensional (3D) models of a bone-level implant system and a titanium base abutment were created using the original implant components. Two titanium implants, measuring 4 × 11 mm each, were selected. The loads were applied in two oblique directions of 15° and 30° under two occlusal movement conditions. In the canine guidance condition, loads (100 N) were applied to the canine crown only. In the group function condition, loads were applied to all three teeth. In this loading, a force of 100 N was applied to the canine, and 200-N forces were applied to each premolar. The stress distribution among all the components of the implant-bridge system was assessed using ANSYS SpaceClaim 2020 R2 software and finite element analysis. RESULTS. Maximum stress was found in the group function occlusion. The maximum stress increased with an increase in the angle of occlusal force. CONCLUSION. The canine guidance occlusion with monolithic zirconia crown materials is promising for implant-supported prostheses in the canine and premolar areas.

• Journal of Korea Multimedia Society
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• v.22 no.5
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• pp.626-637
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• 2019

Due to the rapid development of computer and digital technologies, those technologies were used in advertising. In order to meet the needs of marketing, a virtual space or character using 3D graphic augmented reality technology was developed and applied to advertisement. This study analyzed the characteristics of augmented reality in terms of interface design and spatial expression of augmented reality through case study. Firstly, we wanted to find the relationship between the types of the augmented reality advertisement and interface effects. Secondly, we wanted to find the spatial expression methods. The sample survey case studies based on 42 articles from 2012 to 2018 using Chinese and Korean site sharing augmented reality advertisement. The results of the case studies were divided into two parts. Firstly, the relationship between augmented reality types and interface effects were found basing on the augmented reality index. It means that the augmented reality index can be illustrated by using the augmented reality type. Simultaneously, the augmented reality type can be illustrated using the interface effect. The second part was that the types of display were used as a spatial representation. And the results showed that mobile display and public place display were the most frequently used.

• Journal of Internet Computing and Services
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• v.20 no.1
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• pp.39-46
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• 2019

This paper investigates the importance of various environmental factors that have a strong influence on strawberry yields grown in greenhouse using the pattern recognition methods. The environmental factors influencing the production of strawberries were six factors such as average inside temperature, average inside humidity, average $CO_2$ level, average soil temperature, cumulative solar radiation, and average illumination. The results of analyzing the observed data using Dynamic Time Warping (DTW) showed that the most significant factor influencing the strawberry production was average soil temperature, average inside humidity, and cumulative solar radiation. Second, the results of analyzing the observed data using Multidimensional Scaling (MDS) showed that the most influential factors on the strawberry yields, such as average $CO_2$ level, average inside humidity, and average illumination were differently given for each farms. However, these results are based on the distance in 3D space and can be deduced from the fact that there is not a large difference between these distances. Therefore, in order to increase the harvest of strawberries cultivated in the farms, it is necessary to manage the environmental factors such as thoroughly controlling the humidity and maintaining the concentration of $CO_2$ constantly by ventilation of the greenhouse.

• Applied Microscopy
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• v.49
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• pp.1.1-1.10
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• 2019

Joints of three-dimensional (3D) rutile-type (r) tin dioxide ($SnO_2$) nanowire networks, produced by the flame transport synthesis (FTS), are formed by coherent twin boundaries at $(101)^r$ serving for the interpenetration of the nanowires. Transmission electron microscopy (TEM) methods, i.e. high resolution and (precession) electron diffraction (PED), were utilized to collect information of the atomic interface structure along the edge-on zone axes $[010]^r$, $[111]^r$ and superposition directions $[001]^r$, $[101]^r$. A model of the twin boundary is generated by a supercell approach, serving as base for simulations of all given real and reciprocal space data as for the elaboration of three-dimensional, i.e. relrod and higher order Laue zones (HOLZ), contributions to the intensity distribution of PED patterns. Confirmed by the comparison of simulated and experimental findings, details of the structural distortion at the twin boundary can be demonstrated.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.850-858
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• 1993

Germinatin and early growth of tobacco seedlings in trays containing many cells is increasing in popularity . Since 100 % germination is not likely , a major problem is to locate and replace the content of those cells which contain either no seedling or a stunted seedling with a plug containing a viable seedling. Empty cells and seedlings of poor quality take up valuable space in a greenhouse. They may also cause difficulty when transplanting seedlings into the field. Robotic technology, including the implementation of computer vision, appears to be an attractive alternative to the use of manual labor for accomplishing this task. Operating AGBOT, short for Agricultural ROBOT, involved four steps : (1) capturing the image, (2) processing the image, (3) moving the manipulator, (4) working the gripper. This research seedlings within a cell-grown environment. the configuration of the cell-grown seedling environment dictated the design of a Cartesian robot suitable for working ov r a flat plane. Experiments of AGBOT performance in transferring large seedlings produced trays which were more than 98% survived one week after transfer. In general , the system generated much better than expected.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1491-1496
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• 2009

Because of the development of advanced construction technology, the inner environments of building become more and more complicated, which may result in many problems. The administer may forget where they put up the certain picture, and search for it all over the building, or they underestimate the number of the visitors, and find the situation is out of control, while the pedestrian may get lost, and after making their efforts, they found they turned back to the origin point again. So it is very necessary to establish an indoor spatial database. On one hand, it is able to assist administrator to manage the property and human flow inside the building, on the other hand it could help the pedestrian find the way easily especially when they are not familiar with the building or there is an emergency. This paper focused on how to create the indoor spatial database including both static database and moving objects database. The static database is built on the basis of 3D building models, and the moving objects database gets information from many kinds of cameras and sensors installed in the building. And at the same time the paper discussed the practical use of indoor spatial database mainly in three aspects including consistency management, building restructure, and pedestrian navigation.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3213-3228
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• 2023

As an important part of the digital reactor, the pin-by-pin wise fine coupling calculation is a research hotspot in the field of nuclear engineering in recent years. It provides more precise and realistic simulation results for reactor design, operation and safety evaluation. CORCA-K a nodal code is redeveloped as a robust pin-by-pin wise neutronics and thermal-hydraulic coupled calculation code for pressurized water reactor (PWR) core. The nodal green's function method (NGFM) is used to solve the three-dimensional space-time neutron dynamics equation, and the single-phase single channel model and one-dimensional heat conduction model are used to solve the fluid field and fuel temperature field. The mesh scale of reactor core simulation is raised from the nodal-wise to the pin-wise. It is verified by two benchmarks: NEACRP 3D PWR and PWR MOX/UO₂. The results show that: 1) the pin-by-pin wise coupling calculation system has good accuracy and can accurately simulate the key parameters in steady-state and transient coupling conditions, which is in good agreement with the reference results; 2) Compared with the nodal-wise coupling calculation, the pin-by-pin wise coupling calculation improves the fuel peak temperature, the range of power distribution is expanded, and the lower limit is reduced more.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.68.2-68.2
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• 2020

UVO-Multiband Polarizing Imager System (UVOMPIS) is an ultraviolet to visible light multi-wavelength polarization/imaging system for Compact Advanced Satellite. We developed Linear Astigmatism Free-Three Mirror System (LAF-TMS) D200F2 as an optical system of UVOMPIS which has an entrance pupil diameter of 200 mm, a focal ratio of 2, a field of view of 2° × 4°. LAF-TMS is a confocal off-axis reflecting telescope system that removes linear astigmatism, and its all mirrors (M1, M2, M3) are optimized with the freeform surface to reduce high-order aberrations. Through the sensitivity analysis and Monte-Carlo simulation as the tolerance analysis, we can confirm the feasibility of the system, relatively sensitive parameters (tilt, decenter, despace, surface RMS error), and considerations for optomechanical design. From the sensitivity analysis, we can discover the relatively sensitive optical alignment parameters to a single perturbation. Further more, in the monte-carlo simulation, we investigate the minimum tolerance budget satisfying the required optical performance and whether the tolerance range is satisfied within manufacturing error.