• Progress in Medical Physics
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• v.14 no.3
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• pp.196-202
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• 2003

In 3-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT), many studies on reducing setup error have been conducted in order to focus the irradiation on the tumors while sparing normal tissues as much as possible. As one of these efforts, we developed an image enhancement and registration tool for simulators and portal images that analyze setup errors in a quantitative manner. For setup verification, we used simulator (films and EC-L films (Kodak, USA) as portal images. In addition, digital-captured images during simulation, and digitally-reconstructed radiographs (DRR) can be used as reference images in the software, which is coded using IDL5.4 (Research Systems Inc., USA). To improve the poor contrast of portal images, histogram-equalization, and adaptive histogram equalization, CLAHE (contrast limited adaptive histogram equalization) was implemented in the software. For image registration between simulator and portal images, contours drawn on the simulator image were transferred into the portal image, and then aligned onto the same anatomical structures on the portal image. In conclusion, applying CLAHE considerably improved the contrast of portal images and also enabled the analysis of setup errors in a quantitative manner.

• Tunnel and Underground Space
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• v.30 no.6
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• pp.509-518
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• 2020

This study constructed a new simulation platform, including mesh generation process, numerical simulation, and post-processing for results analysis based on exploration data to perform real-scale numerical analysis considering the actual geological structure efficiently. To build the simulation platform, we applied for open-source programs. The source code is open to be available for code modification according to the researcher's needs and compatibility with various numerical simulation programs. First, a three-dimensional model(3D) is acquired based on the exploration data obtained using a drone. Then, the domain's mesh density was adjusted to an interpretable level using Blender, the free and open-source 3D creation suite. The next step is to create a 3D numerical model by creating a tetrahedral volume mesh inside the domain using Gmsh, a finite element mesh generation program. To use the mesh information obtained through Gmsh in a numerical simulation program, a converting process to conform to the program's mesh creation protocol is required. We applied a Python code for the procedure. After we completed the stability analysis, we have created various visualization of the study using ParaView, another open-source visualization and data analysis program. We successfully performed a preliminary stability analysis on the full-scale Dokdo model based on drone-acquired data to confirm the usefulness of the proposed platform. The proposed simulation platform in this study can be of various analysis processes in future research.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.6
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• pp.491-496
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• 2021

In line with the modern era in which the safety of underground facilities and the use of underground information are increasingly emphasized, the state is pushing for more precise and accurate underground spatial information to be secured and utilized. Therefore, we need to pay more attention to subsurface geospatial data. In the future, the Ministry of Land, Infrastructure and Transport will actively utilize the 15 types of Integrated Underground Geospatial Information Map(6 types of underground facilities, 6 types of underground structures, 3 types of ground) that the Ministry of Land, Infrastructure and Transport is building as three-dimensional underground spatial information, and contribute greatly to improving national safety and convenience in underground construction. expected to do However, when a site manager requests an Integrated Underground Geospatial Information Map with a mobile device, if the large-capacity integrated underground space map is not quickly transmitted over the wireless section and is not serviced, it causes inconvenience to the site manager and delays work. In this paper, the goal of this paper is to enable field managers to quickly receive a tiled Integrated Underground Geospatial Information Map with minimal information exchange. Therefore, the tiling system is configured according to the dataset for high-speed Mobile Integrated Underground Geospatial Information Map transmission. In addition, a transmission system for the Mobile Integrated Underground Geospatial Information Map is established, and a TCP/IP (Transmission Control Protocol/Internet Protocol)-based spatial information tiling transmission protocol dedicated to the on-site Integrated Underground Geospatial Information Map is developed.

• Korean Journal of Applied Biomechanics
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• v.33 no.2
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• pp.73-83
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• 2023

Objective: Adolescent idiopathic scoliosis patients make up 40% of all scoliosis patients, and it is likely to increase even more because of the increase in sitting times due to the pandemic. Method: The subject of this study was a 16-year-old female student. The Cobb's Angle at initial value was 42° at the thoracic and 33° at the lumbar. The subject's height was 161.6 cm, and the type of scoliosis was 3CL. The brace was built with fabric materials with the size information from the X-ray information and actual measurements. The brace was made for the adolescents to wear for a longer time by making them put pressure on the same pressure points of the existing braces. The subjects were required to wear the device for 16 hours every day for three months. Additional features to check the pressure and time were synchronized through an app for easier communication and management with the responsible investigator. Results: After wearing the 3D Fabric brace, Cobb's angle changed from 42° to 33° at the thoracic and 33° to 23° at the lumbar. The ATR changed from 9° to 8° at the thoracic and 11° to 6° at the lumbar. As a result, the changes in the ATR angle do relate to the decrease of Cobb's angle, which made the angle of scoliosis that is bent in a three-dimensional way improve, making the height of the subject increase from 161.6 cm to 163.5 cm. Conclusion: Through this study, developing a brace that is made in the form of the 3CL to align the strap direction and putting pressure on the proper pressure points makes Cobb's angle and the ATR smaller. This means that there is a positive effect on the changes in height. A brace made of light fabric material is a good brace to help treat adolescent idiopathic scoliosis. There was an opinion that it is more comfortable to wear than existing braces, but it seems necessary to conduct a quantitative study about the before and after of wearing the brace and a survey for Korean specific cases.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.637-645
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• 2019

Due to the transformation to the intelligent information society, the rapid change of our life and environment is expected. The Ministry of Science and ICT (MSIT) and the National Research Council of Science and Technology (NST) introduced a five-year government supported research institution's planning and evaluation based on the mid-to long-term perspective. This study collects international benchmarking information including industry, academia, and research fields by collecting mid- and long-term strategy reports from public research institutes, surveys by experts from abroad universities and research institutes, and analyzing overseas market information reports. The British Geological Survey (BGS), the U.S. Geological Survey (USGS) and the japanese geological survey related institutes (AIST-GSJ) plans for three-dimensional national geological information, predictions of geological environmental disasters, and development of important metals and material in the low carbon economic transformation and in the era of the Fourth Industrial Revolution. The mid- and long-term program emphasizes basic and public research on geological information through abroad experts survey such as the IPGP-CNRS etc. The market analysis of the mining automation and digital map sectors has been able to derive the fields in which the role of public research institutes by the market is expected such as data collection on land and in the air, mobile or three-dimensional information production, smooth/fast/real-time maps, custom map design, mapping support to various platforms, geological environmental risk assessment and disaster management information and maps.

• Imaging Science in Dentistry
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• v.49 no.4
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• pp.295-299
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• 2019

Purpose: This clinical pilot study was performed to determine the effectiveness of dual-energy cone-beam computed tomography (DE-CBCT) in measuring bone mineral density (BMD). Materials and Methods: The BMD values obtained using DE-CBCT were compared to those obtained using calibrated multislice computed tomography (MSCT). After BMD calibration with specially designed phantoms, both DE-CBCT and MSCT scanning were performed in 15 adult dental patients. Three-dimensional (3D) Digital Imaging and Communications in Medicine data were imported into a dental software program, and the defined regions of interest (ROIs) on the 3-dimensional surface-rendered images were identified. The automatically-measured BMD values of the ROIs (g/㎤), the differences in the measured BMD values of the matched ROIs obtained by DE-CBCT and MSCT 3D images, and the correlation between the BMD values obtained by the 2 devices were statistically analyzed. Results: The mean BMD values of the ROIs for the 15 patients as assessed using DE-CBCT and MSCT were 1.09±0.07 g/㎤ and 1.13±0.08 g/㎤, respectively. The mean of the differences between the BMD values of the matched ROIs as assessed using DE-CBCT and calibrated MSCT images was 0.04±0.02 g/㎤. The Pearson correlation coefficient between the BMD values of DE-CBCT and MSCT images was 0.982 (r=0.982, P<0.001). Conclusion: The newly developed DE-CBCT technique could be used to measure jaw BMD in dentistry and may soon replace MSCT, which is expensive and requires special facilities.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1663-1670
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• 2006

Single crystal Fe thin films were grown directly onto n-Si(111) substrates by pulsed electrodeposition. Cyclic Voltammogram(CV) indicated that the $Fe^{2+}/n-Si(111)$ interface shows a good diode behavior by forming a Schottky barrier. From Mott-Schottky (MS) relation, it is found that the flat-band potential of n-Si(111) substrate and equilibrium redox potential of $Fet^{2+}$ ions are -0.526V and -0.316V, respectively. The nucleation and growth kinetics at the initial reaction stages of Fe/n-Si(111) substraste was studied by current transients. Current transients measurements have indicated that the deposition process starts via instantaneous nucleation and 3D diffusion limited growth. After the more deposition, the deposition flux of Fe ions was saturated with increase of deposition time. from the as-deposited sample obtained using the potential pulse of 1.4V and 300Hz, it is found that Fe nuclei grows to three dimensional(3D) islands with the average size of about 100nm in early deposition stages. As the deposition time increases, the sizes of Fe nuclei increases progressively and by a coalescence of the nuclei, a continuous Fe films grow on the Si surface. In this case, the Fe films show a highly oriented columnar structure and x-ray diffraction patterns reveal that the phase ${\alpha}-Fe$ grows on the n-Si(111) substrates.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.6
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• pp.637-652
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• 2015

In the present work, a number of three-dimensional (3D) parametric numerical analyses have been carried out to study the influence of tunnelling on the behaviour of adjacent piles considering the transverse distance of the pile tip from the tunnel. Single piles and $5{\times}5$ piles inside a group with a spacing of 2.5d were considered, where d is the pile diameter. In the numerical modelling, several key issues, such as the tunnelling-induced pile settlements, the interface shear stresses, the relative shear displacements, the axial pile forces, the apparent factors of safety and zone of influence have been rigorously analysed. It has been found that when the piles are inside the influence zone, the pile head settlements are increased up to about 111% compared to those computed from the Greenfield condition. Larger pile settlements and smaller axial pile forces are induced on the piles inside the pile groups than those computed from the single piles since the piles responded as a block with the surrounding ground. Also tensile pile forces are induced associated with the upward resisting skin friction at the upper part of pile and the downward acting skin friction at the lower part of pile. On the contrary, when the piles were outside the influence zone, tunnelling-induced compressive pile forces developed. Based on computed load and displacement relation of the pile, the apparent factor of safety of the piles was reduced up to about 45%. Therefore the serviceability of the piles may be substantially reduced. The pile behaviour, when considering the single piles and the pile groups with regards to the influence zone, has been analysed by considering the key features in great details.

• Journal of Plant Biology
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• v.34 no.2
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• pp.121-127
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• 1991

Total soluble proteins from three developmental stages of induced root nodules of Canavalia lineata were compared with those of non-nodulated roots by SDS-PAGE and two dimensional (2-D) gel electrophoresis. Thirteen nodule-specific protein (nodulin) bands were identified by the former and 30 nodule specific protein spots were detected by the latter method respectively. Some of the nodulins were detected differentially depending on the nodule's developmental stages. For example, only three leghemoglobin (Lb)-like protein spots appeared at stage I (d<2 mm), but two additional Lb-like protein spots appeared at stage II (d <4-5 mm). pI value and molecular weight of nomomers of Lb-like protein were narrower and greater than those of soybean, ranging from 4.4 to 5.0 and 15.7 kd respectively. Northern blot hybridization of total RNAs from roots and root nodules using soybean Lb cDNA as a probe made it clear that Lb gene was expressed tissue-specifically only in the root nodules.odules.

• Particle and aerosol research
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• v.13 no.3
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• pp.111-118
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• 2017

Electrohydrodynamic (EHD) printing with the aid of strong electric fields can generate and pattern droplets that are smaller than droplets by other printing technologies. Conventional EHD printing has created two-dimensional (2D) patterns by moving its nozzle or a substrate in X and Y directions. In this study, we aimed to develop an EHD system that can create 2D patterns using a multielectrode array (MEA) without moving a nozzle or substrate. In particular, printing ink mixtures of biodegradable polymers and model dyes was patterned on a thin film made of another biodegradable polymer. Without movement of a nozzle and substrate, stable 2D patterning of minimum $6{\mu}m$ size over a range of about 1 mm away from the nozzle position was achieved by MEA control only. We also demonstrated the possibility of denser 2D pattering of the ink mixtures by moving a target substrate relative to MEA position.