• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.209-216
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• 2018

High-resolution satellite imagery is used in diverse fields such as meteorological observation, topography observation, remote sensing (RS), military facility monitoring and protection of cultural heritage. In satellite imagery, low-resolution imagery can take place depending on the conditions of hardware (e.g., optical system, satellite operation altitude, image sensor, etc.) even though the images were obtained from the same satellite imaging system. Once a satellite is launched, the adjustment of the imaging system cannot be done to improve the resolution of the degraded images. Therefore, there should be a way to improve resolution, using the satellite imagery. In this study, a super resolution (SR) algorithm was adopted to improve resolution, using such low-resolution satellite imagery. The SR algorithm is an algorithm which enhances image resolution by matching multiple low-resolution images. In satellite imagery, however, it is difficult to get several images on the same region. To take care of this problem, this study performed the SR algorithm by calibrating geometric changes on images after applying automatic extraction of feature points and projection transform. As a result, a clear edge was found just like the SR results in which feature points were manually obtained.

• The Korean Journal of Mycology
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• v.48 no.1
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• pp.15-27
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• 2020

In screening for antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) KCCM 40510 and Bacillus cereus KCTC 3624, NNIBRFG5039 was isolated from the air in Sangju-si, Gyeongsangbuk-do. Based on a high sequence similarity of the internal transcribed spacer (ITS) region, NNIBRFG5039 was determined to be closely related to Penicillium rubefaciens CBS 139145. The optimal media, initial pH, and temperature for mycelial growth and antimicrobial activity of P. rubefaciens NNIBRFG5039 were determined as follows: potato dextrose broth (PDB), pH 6.5, and 30℃, respectively. Under the optimal culture conditions, maximum mycelial growth (12.4 g L^-1) and antibacterial activity (7.5 mm zone of inhibition against MRSA KCCM 40510, and 5.0 mm zone of inhibition against B. cereus KCTC 3624) were observed in a 5 L stirred-tank fermenter. We also isolated the antimicrobial compound from an ethyl acetate fraction, and its chemical structure was identified as (S)-6-hydroxymellein (1) by ESI-MS, ¹H-NMR, and ¹³C-NMR. Consequently, the extract from P. rubefaciens NNIBRFG5039 may be used in functional materials for antimicrobial-related applications.

• Journal of Trauma and Injury
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• v.27 no.4
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• pp.170-177
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• 2014

Purpose: The first regional trauma center selected in Korea was the Gachon University Gil hospital regional trauma center; expectation on its role has been high because of its location in the Seoul metropolitan region. To determine if those expectations are being met, we analyzed the patients visiting the center and their treatment experiences for the past 3 years in order to propose a standard for the operation of a trauma center. Methods: The visiting route, visiting methods, performance of emergency surgery, the ward and the length of stay, the injury mechanism, the injury severity score (ISS), the department that managed the surgery, and the cause of death were analyzed for 367 patients visiting the center from its establishment in June 2011 through December 2013. Results: The mean age of the patients was 47 years (285 male and 82 female patients). A total of 187 patients directly visited the center whereas 180 were transferred to the center. Traffic accidents comprised the majority of injury mechanisms, and 178 patients underwent emergency surgery. The mean length of stay per patient was 11 days for those in the ICU and 27 days for those in a general ward. These patients occupied 4 beds in the ICU and 10 beds in the general ward per day. A total of 1.21 surgeries were performed per patient, and the mean number of surgeries performed per day was 0.49. The mean ISS was 15.91, and 183 patients (50%) had an ISS of ${\geq}16$. Thirty-one patients died; they had a mean ISS of 28.42. The most frequent cause of death was multi-organ failure. The mean number of treatment consultations during a patient's stay was 6.32. Forty-five patients (13%) were discharged from the center, and 291 (79%) were transferred to another hospital. Conclusion: A systematic approach to establishing a treatment model for trauma patients, including injury mechanism, multidisciplinary treatment, and trauma surgeon intervention, is required for treating trauma patients.

• Korean Journal of Head & Neck Oncology
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• v.25 no.1
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• pp.12-17
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• 2009

Background and Objectives : Branchial anomaly is a common neck pathology seen by otolaryngologist. Although there is still controversy regarding the origin, almost all surgeon agree that branchial anomalies result from incomplete involution of the branchial apparatus. Depending on its anatomic location, branchial anomalies can be classified into first, second, third and fourth anomaly. The purpose of this study is to evaluate the incidence of different categories of branchial anomalies and to determine proper method of diagnosis and treatment. Subjects and Method : A retrospective chart review was conducted for 72 patients with branchial anomalies operated on at the Korea University Anam Hospital from 1996 to 2007. The patient's sex, age, presenting symptoms, classification, site of lesion, diagnostic studies, surgical therapy and post-operative surgical complication were reviewed. Results : Patients were commonly seen in the 3rd decades. Eleven patients(15.3%) were first branchial anomalies, 52(72.2%) were second, 1(1.4%) was third, and 8(11.1%) were fourth. Of the types of anomalies, cyst were most commonly seen. In cases of 3rd and 4th branchial anomalies, barium contrast study can delineate the course of sinus or fistula. All cases was operated on for branchial anomalies, there were no major post-operative complication. Conclusion : Cervical mass and recurrent cervical infection or abscess are suspect for branchial anomalies. Especially, clinical history of dysphagia, and recurrent painful swelling in the thyroid region in young patients should raise the suspicion of 3rd and 4th branchial anomalies. Careful history, clinical examination and radiographic study were essential parts in diagnosis of branchial anomalies. Although surgical management of branchial anomalies depend on its type, nature and extent, complete excision is the major surgical procedure.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.41-46
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• 2007

The residential fuel cell system was modeled as a box-shaped chamber with vent openings, filled with various components such as reformer, desulfurizer, fuel cell stack and humidifier. When the vent openings are 1% of the total surface and hydrogen leakage 1%, hydrogen concentration is around 0.1% higher than the other regions from leak points in the chamber at 30 seconds and hydrogen concentration is increased from 0.3% to 0.7% in the upper region of the system after 200 seconds. When the vent openings are 1% of the total surface and hydrogen leakage 1%, 3%, 5%, the steady state result of CFD, 5% of hydrogen leakage is reached the lowest ignition limit in the system. When the vent openings are 2% of the total surface and hydrogen leakage 1%, hydrogen concentration is increased in the bottom of the system for 60 seconds. After 250 seconds, hydrogen concentration is reached the steady state in the system. As the vent opening of the total surface increased from 1% to 2%, averaged hydrogen mole fraction is under 1% in the system, however, upper regions of the system from the hydrogen leakage points are shown over 1% of hydrogen mole fraction.

• Investigative Magnetic Resonance Imaging
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• v.7 no.2
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• pp.137-143
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• 2003

Purpose : B1 field of birdcage RF (radiofrequency) coil that is used most for brain imaging in magnetic resonance imaging (MRI) decreases toward endring from the coil center. We investigated how much RE B1 homogeneity effect the endcap shield brings form the coil center as it towards to endcap region. Materials and Methods : We compared RF B1 field distribution by each finite difference time domain (EDTD) simulations for lowpass, highpass and hybrid birdcage RF coils. We selected the highpass birdcage RF coil that was the highest RF B1 field condition as simulation result, and studied how much RF B1 homogeneity effect was occurred when endcap shield was applied to endring area. Results : B1 field of the highpass birdcage RF coil was higher than other birdcage RF coil types as simulation result. However, the RF B1 homogeneity was lower than other coil types. RE B1 field of highpass birdcage RF coil with endcap shield is similar with RF B1 field of hybrid birdcage RF coil and the overall RE B1 homogeneity in sagittal direction was better. Conclusion In this paper, proposed method can apply improving RF B1 homogeneity of RF coil in clinical examination.

• Journal of Radiation Protection and Research
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• v.16 no.2
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• pp.41-54
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• 1991

This paper aimed to analyse dose sensitivity to the controllable parameters of indoor radon $(^{222}Rn)$ and its decay products (Rn-D) by applying the input~output linear system theory. Physical behaviors of $^{222}Rn\;&\;Rn-D$ were analyzed in terms of $(^{222}Rn)$ gas -generation, -migation and -infiltration to indoor environments, and the performance output-function, i. e. mean dose equivalent to Tracho-Bronchial (TB) lung region, was assessed to the following extented ranges of the controllable paramenters; a) the ventilation rate $constant({\lambda}_v)\;:\;0{\sim}50[h^{-l}].\;b)$ the attachment rate $constant({\lambda}_a)\;:\;0{\sim}500[h^{-l}].\;c)$ the unattached-deposition rate constant (${\lambda}^u_d)\;:\;0-50[h-l]$. A linear input-output model was reconstructed from the original models in literatures, as follows, which was modified into the matrices consisting of 111 nodal equations; a) indoor $^{222}Rn\;&\;Rn-D$ Behaviour; Jacobi-Porstendoerfer-Bruno model.

• Journal of Korea Water Resources Association
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• v.41 no.3
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• pp.293-303
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• 2008

Reservoir turbidity flows degrade the efficiency and sustainability of water supply system in many countries located in monsoon climate region. A decision support system called RTMMS aimed to assist reservoir operations was developed for the real time monitoring, modeling, and management of turbidity flows induced by flood runoffs in Daecheong reservoir. RTMMS consists of a real time data acquisition module that collects and stores field monitoring data, a data assimilation module that assists pre-processing of model input data, a two dimensional numerical model for the simulation of reservoir hydrodynamics and turbidity, and a post-processor that aids the analysis of simulation results and alternative management scenarios. RTMMS was calibrated using field data obtained during the flood season of 2004, and applied to real-time simulations of flood events occurred on July of 2006 for assessing its predictive capability. The system showed fairly satisfactory performance in reproducing the density flow regimes and fate of turbidity plumes in the reservoir with efficient computation time that is a vital requirement for a real time application. The configurations of RTMMS suggested in this study can be adopted in many reservoirs that have similar turbidity issues for better management of water supply utilities and downstream aquatic ecosystem.

• Korean Journal of Plant Resources
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• v.21 no.4
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• pp.281-291
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• 2008

This study was carried out to clarify the distribution of vascular plants and their usefulness in Podosan of Yeongyang, Gyeongbuk (748m, N $36^{\circ}$ $31^{\prime}$ $79.1^{\prime\prime}$$\sim$$36^{\circ}$ $30^{\prime}$ $16.8^{\prime\prime}$$\sim$, E $129^{\circ}$ $12^{\prime}$ $43.8^{\prime\prime}$$\sim$$129^{\circ}$ $14^{\prime}$ $07.1^{\prime\prime}$). The vascular plants collected 5 times (from May to September 2007) were consisted of total 437 taxa; 88 famailies, 267 genera, 384 species, 4 subspecies, 43 varieties and 6 forms. Among them, edible, medicinal, industrial, ornamental and usefulness unknown plants were 211 taxa, 229 taxa, 85 taxa, 71 taxa, 105 taxa, respectively. Korean endemic plants of this area were 9 taxa, and the special plants species based on floral region by Ministry of Environment were 13 taxa in grade III category, 4 taxa in grade IV category. The naturalized plants were 17 taxa, therefore naturalized ratio was 3.9%, and urban index 6.3%.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.7 no.1
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• pp.39-44
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• 2014

The patellar clunk syndrome is one of the patellofemoral complication, caused by formation of the fibrous nodule at the suprapatellar region after total knee arthroplasty. The symptom involves painful catching, crepitus and clunk during knee extension. It has been mainly but not exclusively associated with the posterior stabilized total knee system. The fibrous nodule is entrapped in the femoral intercondylar notch of the femoral component during flexion and as the knee is extended, it displaces back to the trochlear groove abruptly and the typical symptoms occur. The risk of developing this complication is primarily related to the design of the femoral component and higher incidence was noted with earlier designs of posterior stabilized knee prosthesis. Modifications have been made to the femoral component to optimize the kinematics of the patellofemoral joint and thereby reduced the incidence of patellar clunk syndrome but did not eliminate the problem completely. Clinical examination is the gold standard of diagnosis and imaging study has been used as a possible adjunct to diagnosis. Especially ultrasonography is an imaging modality, which can be easily performed to detect the fibrous nodule on the quadriceps tendon. We report a case of patellar clunk syndrome which was diagnosed with ultrasonography.