• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.76-80
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• 2009

Purpose: The uptake of $^{99m}Tc$-MIBI increases in the parathyroid adenoma, hyperplasia, and carcinoma. The purpose of this study is to evaluate and compare the results of the biopsy with quantitative analysis results in the localized parathyroid lesions (adenoma, hyperplasia, and carcinoma). Materials and Methods: From April 2002 to January 2009, double-phase $^{99m}Tc$-MIBI parathyroid scan (early 15 min, delayed 2 hrs) was performed after injection of 750 MBq of $^{99m}Tc$-MIBI in 27 diagnosed parathyroid patients (adenoma:15, hyperplasia:4, carcinoma:8). For quantitative analysis, early, delayed lesion to non-lesion ratios (L/NLs), washout rate (%, WR) and vertical axis were calculated. Results: In early images, lesion to non-lesion ratios were $1.53{\pm}0.41$ (adenoma), $1.38{\pm}0.27$ (hyperplasia) and $1.45{\pm}0.64$ (carcinoma). In delayed images, lesion to non-lesion ratios were $1.56{\pm}0.43$ (adenoma), $1.33{\pm}0.10$ (hyperplasia), $1.83{\pm}0.79$ (carcinoma). In vertical axis, the sizes were $2.11{\pm}0.67$ (adenoma), $2.23{\pm}0.75$ (hyperplasia) and $2.20{\pm}0.97$ (carcinoma). There was no statistical difference between lesion to non-lesion ratios and the size of vertical axis (p>0.05). However, washout rates were $31.59{\pm}13.97$ (adenoma), $37.8{\pm}5.69$ (hyperplasia), $17.73{\pm}11.02$ (carcinoma). As a result, there was a significant difference statistically between and that of carcinoma (p<0.05, p=0.028 by Kruskal-willis statistic, Dunn's Multiple comparison test SPSS Ver 12.0). Conclusions: There was no statistical difference between the lesion to non-lesion ratios and the size of vertical axis. However, there was a significant difference statistically between WR of hyperplasia and that of carcinoma.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.4
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• pp.257-267
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• 2024

Partially edentulous patients with a crossed occlusion have poor denture support, retention, and stability. Moreover, residual abutments showed a poor prognosis due to denture rotation. The use of a conical double crown removable partial denture to establish proper horizontal and vertical interocclusal relationships, it can establish a stable occlusal plane and occlusal contacts providing a sufficient restorative space and a favorable functional and aesthetic outcome. In this case, a patient with an anterior-posterior crossed occlusion with mandibular prognathism and no occluding teeth in habitual centric position was treated with a conical double crown removable partial denture. After diagnostic cast analysis and digital diagnosis, provisional prosthesis templates were fabricated. It was possible to intuitive and appropriate vertical dimension determination and esthetic evaluation were performed. Definitive prosthesis with proper function and aesthetics can be fabricated by the digital and conventional treatment process.

• The Korean Journal of Nuclear Medicine
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• v.33 no.6
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• pp.519-526
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• 1999

Purpose: This study was designed to evaluate the usefulness of a technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) single photon emission computed tomography (SPECT) performed on transplanted kidney. Materials and Methods: Thirty renal transplant patients were included in this study. Planar scan was performed for 30 minutes using 555 MBq Tc-99m MAG3. A post-voiding SPECT scan was acquired on the third, seventh, fourteenth and twenty eighth day after transplantation. Results: SPECT scan showed interpretable image quality in 26 of 30 patients (86.7%) and 84 in 120 scans (70%). Fourteen of 26 patients with interpretable SPECT image showed decreased or increased radioactivity, but only 5 had abnormal findings on the planar scan. Focal SPECT defects were seen in allografts with normal function (n=3), acute tubular necrosis (n=3), and acute rejection (n=2). The defects are thought to reflect focally underperfused renal parenchyme or, in normal allografts, an artifact from uneven radioactivity distribution. Four of 10 patients with renal arterial variation showed focally decreased radioactivity and SPECT helped guide funker studies that confirmed the exact cause. Five of 10 patients with acute tubular necrosis or acute rejection showed focally decreased radioactivity, but its relation to the patients' clinical course was not clear. Focally increased radioactivity was observed in 5 allografts with normal function and 1 with double ureter in which local clearance delay was observed. Conclusion: Tc-99m MAG3 SPECT renal scan can detect additional focal abnormalities compared to planar scan. Further study is necessary to elucidate the exact clinical significance of the SPECT findings.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.93-98
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• 2010

In this work, the electrochemical properties of surface treated multi-walled carbon nanotubes (MWNTs) were studied. Nitrogen and oxygen functional groups of the MWNTs were introduced by urea and acidic treatment, respectively. The surface functional groups of the MWNTs were confirmed by X-ray photoelectron spectroscopy (XPS) measurements and zeta-potential method. The characteristics of $N_2$ adsorption isotherm at 77 K, specific surface area, and total pore volumes were investigated by BET eqaution, BJH method and t-plot method. Electrochemical properties of the functionalized MWNTs were accumulated by cyclic voltammetry at the scan rates of 50 $mVs^{-1}$ and 100 $mVs^{-1}$ in 1M $H_2SO_4$ as electrolytes. As a result, the functionalized MWNTs led to an increase of capacitance as compared with pristine MWNTs. It was found that the increase of capacitance for urea treated MWNTs was attributed to the increase in density of surface functional groups, resulting in improving the wettability between electrode materials and charge species.

• Korean Journal of Materials Research
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• v.24 no.6
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• pp.285-292
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• 2014

Commercial activated-carbon used as the electrode material of an electric double-layer capacitor (EDLC) was posttreated with various acids and alkalis to increase its capacitance. The carbon samples prepared were then heat-treated in order to control the amount of acidic functional groups formed by the acid treatments. Coin-type EDLC cells with two symmetric carbon electrodes were assembled using the prepared carbon materials and an organic electrolyte. The electrochemical performance of the EDLC was measured by galvanostatic charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy. Among the various activated carbons, the carbon electrodes (CSsb800) prepared by the treatments of coconutshell-based carbon activated with NaOH and $H_3BO_5$, and then heat treated at $800^{\circ}C$ under a flow of nitrogen gas, showed relatively good electrochemical performance. Although the specific-surface-area of the carbon-electrode material ($1,096m^2/g$) was less than that of pristine activated-carbon ($1,122m^2/g$), the meso-pore volume increased after the combined chemical and heat treatments. The specific capacitance of the EDLC increased from 59.6 to 74.8 F/g (26%) after those post treatments. The equivalent series resistance of EDLC using CSsb800 as electrode was much lower than that of EDLC using pristine activated carbon. Therefore, CSsb800 exhibited superior electrochemical performance at high scan rates due to its low internal resistance.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.146-151
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• 2008

Multiple primary malignant neoplasm of the combination of the musculoskeletal system and the gastrointestinal system were very rare. A case of synchronous double primary malignant neoplasm consisted of myxofibrosarcoma of forearm and adenocarcinoma of rectum in a 52 year-old man was found. The patient had pain and swelling on forearm for 1 year. Histologically, the lesion on forearm showed myxofibrosarcoma. In systemic evaluation, the adenocarcinoma of rectum was found by the sigmoidoscopy, and metastasis on lung and intracardiac mass were found by the CT scan. We performed surgical excision and pre and postoperative chemotherapy after pathologic confirmation. He died of pulmonary thromboembolism after postoperative 2 months. We report this case of exceedingly rare combination of the musculoskeletal system and the gastrointestinal system.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.25 no.2
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• pp.68-78
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• 2016

Recently, digital technology has become increasingly prevalent in the dental clinic. Using a milling machine for clinic, it is possible to produce provisional restoration inside the clinic. This can promote large clinical cases such as full mouth rehabilitation with the help of a tabletop scanner, which is capable of semi-adjustable articulator equipment, and a powerful dental CAD software with excellent user convenience. In this case report, a full-mouth rehabilitation was done with digital technology to a 55 year-old female patient, who has lost vertical dimension through the attrition, and has got inclined occlusal plane with unplanned and repeated dental reconstruction. Through the design and milling of the provisional restoration in the clinic and the duplication of these provisionals by double scanning technique, a good functional and esthetic result could be achieved.

• New Physics: Sae Mulli
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• v.68 no.11
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• pp.1167-1172
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• 2018

Carbon nanotubes (CNTs) are structures of carbon atoms bonded together in hexagonal honeycomb shapes, with multi-walled CNTs having a very high thermal conductivity of $3000W/m{\cdot}K$ and single-walled CNTs having a conductivity of $6000W/m{\cdot}K$. In this work, the transmittance and the thermal diffusivity of a multi-walled carbon nanotube dispersion with a concentration of 1.5 M were measured using a single beam method, a dual beam method, and the thermal lens effect. The nonlinear optical coefficients were obtained by using the z-scan method, which moved the sample in the direction of propagation of the single laser beam, propagation and the thermal diffusivity was measured using a double laser beam. As a pump beam, a diode-pumped solid state (DPSS) laser with a wavelength of 532 nm and an intensity of 100 mW was used. As the probe beam, a He-Ne laser having a wavelength of 633 nm and an intensity of 5 mW was used. The experimental result shows that when the concentrations of the sample were 9.99, 11.10, 16.65, and 19.98 mM, the nonlinear absorption coefficients were 0.046, 0.051, 0.136 and 0.169 m/W, respectively. Also, the nonlinear refractive indices were 0.20, 0.51, 1.25 and $1.32{\times}10^{-11}m^2/W$, respectively, and the average thermal diffusivity was $1.33{\times}10^{-6}m^2/s$.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.107-118
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• 2021

Scan-to-BIM can be precisely mod eled by measuring structures with Light Detection And Ranging (LiDAR) and build ing a 3D BIM (Building Information Modeling) model based on it, but has a limitation in that it consumes a lot of manpower, time, and cost. To overcome these limitations, studies are being conducted to perform semantic segmentation of 3D point cloud data applying deep learning algorithms, but studies on how segmentation result changes depending on learning data are insufficient. In this study, a parametric study was conducted to determine how the size and track type of railroad tunnels constituting learning data affect the semantic segmentation of railroad tunnels through deep learning. As a result of the parametric study, the similar size of the tunnels used for learning and testing, the higher segmentation accuracy, and the better results when learning through a double-track tunnel than a single-line tunnel. In addition, when the training data is composed of two or more tunnels, overall accuracy (OA) and mean intersection over union (MIoU) increased by 10% to 50%, it has been confirmed that various configurations of learning data can contribute to efficient learning.