• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1680-1683
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• 2003

To describe the performance of an antenna, some parameters are necessary. Some of the parameters are interrelate and not all of them must be specified for complete description of antenna performance. The parameters in characteristics of printed antenna for this analysis are radiation pattern, input impedance, VSWR, S parameter and electromagnetic field. In this paper we will consider two shaped of slot antennas one is triangular slot antenna and other is L - shape slot antenna for compare the radiation pattern, return loss, and VSWR. Two slot antennas are designed to have a resonant frequency at 10 GHz. The microstrip line is designed to be 50 ohms in order to match the measurement system, it has the substrate of the thickness = 1.52 mm and dielectric constant (${\varepsilon}_r$) 2.17. The problem space in the FDTD analysis are $60{\times}123{\times}100$ cells for L-shape slot antenna and $50{\times}171{\times}120$ cells for triangular slot antenna with the cell dimensions ${\Delta}x=0.152\;mm.$, ${\Delta}y={\Delta}z=0.15\;mm.$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.208-213
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• 2016

The re-identification of two Korean tonguefishes, Cynoglossus interruptus and Symphurus orientalis, was carried out using eight specimens collected from Korean waters in 2007 and 2013. C. interruptus is characterized by having a single row of scales between rows connected to the supraorbital line and the middle lateral line, 107–113 dorsal fin rays, 86–89 anal fin rays, and 53–55 vertebrae. S. orientalis is characterized by having a 1-2-2-2-2 ID pattern, 97–100 dorsal fin rays, 83–89 anal fin rays, and 52–55 vertebrae. Molecular analysis using mitochondrial DNA Cytochrome Oxidase subunit I sequences showed that specimens of the two species corresponded well to Japanese C. interruptus and Taiwanese S. orientalis, respectively. Therefore, although several reports have raised questions regarding the distribution of C. interruptus and S. orientalis in Korean waters, morphological and molecular data confirm that these two species are indeed distributed in these waters.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.307-313
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• 2012

The Oriental White Stork (Ciconia boyciana) is a representative wetland species distributed across East Asia. The species has been declined to face the threat of species extinctions with estimation of at about 3000 individuals. In order to re-introduce the endangered storks in the field, we developed a baseline model using the program VORTEX, performed sensitivity test, and finally suggested an ideal model based on results of the sensitivity test. The baseline model predicted 12.5% extinction probability with mean time to first extinction of 82.0 year. Sensitivity test revealed that two demographic variables (first-year mortality and percent of adult female breeding) had the greatest impacts on population persistence. Thus, corrected model improved the population persistence, where the extinction probability decreased to 1.0% in 100 years by changing values of two variables within a range of applicable to the population. Our models for stork re-introduction suggest this population will be stable by improving first-year mortality and adult female fecundity.

• Transactions on Electrical and Electronic Materials
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• v.12 no.6
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• pp.258-261
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• 2011

A ferroelectric $(Bi,La)_4Ti_3O_{12}$ (BLT) thin film fabricated by the pulsed-DC sputtering method was evaluated on a cell structure to check its compatibility to high density ferroelectric random access memory (FeRAM) devices. The BLT composition in the sputtering target was $Bi_{4.8}La_{1.0}Ti_{3.0}O_{12}$. Firstly, a BLT film was deposited on a buried Pt/$IrO_x$/Ir bottom electrode stack with W-plug connected to the transistor in a lower place. Then, the film was finally crystallized at $700^{\circ}C$ for 30 seconds in oxygen ambient. The annealed BLT layer was found to have randomly oriented and small ellipsoidal-shaped grains (long direction: ~100 nm, short direction: ~20 nm). The small and uniform-sized grains with random orientations were considered to be suitable for high density FeRAM devices.

• Journal of Magnetics
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• v.12 no.1
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• pp.40-44
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• 2007

The Planar Hall effect in a spin valve structure has been applied as a biosensor being capable of detecting $Dynabeads^{(R)}$ M-280. The sensor performance was tested under the application of a DC magnetic field where the output signals were obtained from a nanovoltmeter. The sensor with the pattern size of $50{\times}100{\mu}m^2$ has produced high sensitivity; especially, the real-time profiles by using that sensor revealed significant performance at external applied magnetic field of around 7.0 Oe with the resolution of 0.04 beads per $\mu m^2$. Finally, a successful array including 24 patterns with the single sensor size of $3{\times}3{\mu}m^2$ has shown the uniform and stable signals for single magnetic bead detection. The comparison of this sensor signal with the others has proved feasibility for biosensor application. This, connecting with the advantages of more stable and high signal to noise of PHR sensor's behaviors, can be used to detect the biomolecules and provide a vehicle for detection and study of other molecular interaction.

• Membrane Journal
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• v.4 no.4
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• pp.221-231
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• 1994

The GR51PP(MWCO 50,000) and GR40PP(MWCO 100,000) membranes manufactured by DDS were used in ultrafiltration of dextran(Mw. : 500,000) solution in flat plate ultrafiltration cell filled with various types of turbulence promoters. The flux improvement by using turbulence promoter was higher in laminar flow region than in turbulent flow region. The maximum improvements of permeate flux were foud as 112% and 50% I laminar flow region and turbulent flow region, respectively. Also, the solute rejection of the ultrafiltration membrane was improved by turbulence promoters and its effect was significant in the high transmembrane pressure and laminar flow region. The smaller the spacer mesh size was used, the higher the flux improved, but the pressure drop in ultrafiltration cell also increased. In laminar flow region, pressure drop by the spacer was negligible, but in turbulent flow region it changed significantly depending upon the mesh size of the spacer and therefore, its mesh size must be baken into account in the design of the process. The predicted results of the modified mass transfer correlation had better agreement with experimental results than those of unmodified one, The modified mass transfer correlations for laminar and turbulent flow region are shown as follow. $N_{sh}=0.151(N_{Re})^{0.199}(N_{Sc})^{0.22}(N_{Scm})^{0.197}\;(625 $N_{sh}=0.0165(N_{Re})^{0.428}(N_{Sc})^{0.33}(N_{Scm})^{0.223}\;(5015

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.2 no.2
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• pp.53-61
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• 2009

Purpose: This study was designed to evaluate the clinical usefulness of serial ultrasonography (USG) after arthroscopic rotator cuff repair and to assess the re-tear rate and the re-tear time according to the tear sizes and the repair method. Materials and Methods: Between January 2008 and June 2008, 52 patients were treated with arthroscopic rotator cuff repair, Of the 52 patients, 29 patients that had undergone more than six months follow-up underwent preoperative USG examinations and subsequent arthroscopic examinations. MRI and USG findings were compared with intraoperative results of arthroscopic examinations. The postoperative integrity of the rotator cuff was observed using serial USG examination performed postoperatively at two weeks, six weeks, three months, and six months. Results: Small to medium rotator cuff tear were identified in 10 patients where the double pulley suture bridge (DPSB) technique was performed; the re-tear rate was 20%. For 19 patients with large to massive rotator cuff tears, the re-tear rates was 100% for six patients who had undergone tendon to tendon (TT) repair, the re-tear rate was 50% for two patients who had undergone tendon to tendon and bone to tendon (TTBT) repair and the re-tear rate was 55% for11 patients where the DPSB technique was performed. Re-tear rates according to follow-up periods were 7% from two to six weeks, 66% from six weeks to three months and 27% from three to six months postoperatively. Conclusion: Serial USG examinations after arthroscopic rotator cuff repair were useful to assess the re-tear rate and the re-tear time. In addition, USG examination were useful for treatment planning during postoperative rehabilitation.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.9-16
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• 2002

The particles velocity in the instantaneous flow field and velocity change of particles along the jet centerline for various particle diameter in a circular turbulent impingement jet are investigated by using particle image velocimetry(PIV) and an equation of particle motion simplified by terms of inertia forces, drag and gravitational force. The jet Reynolds number was 3300 and 8700, and glass beads of 30,58 and 100$\mu$m in diameter were used. The PIV results show that the direction and size of velocity depends not only on the number density of particle but also on the particle momentum. The results obtained form calculation suggest that the particle velocity near the first impingement region deviated from local air velocity, which accords well with the PIV results. The rebound height of particle increase with the particle diameter. In the second-impingement, particle velocities increased sluggishly with Re=3300 but particle velocities uniformed with Re=8700 in stagnation region.

• Journal of Chest Surgery
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• v.26 no.4
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• pp.325-328
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• 1993

The pedicled omental flap has been used for treatment of various kind of complications in thoraxcic surgery. Its property of promoting neovascularization , immunilogic properties that limiting the spread of infection, providing soft tissue coverage are very effective in treatment esophageal fistulas. Also, congenital broncho-esophageal fistula [ BEF ] is a rare disease entity which was reported about 100 cases around the world. We experienced 27 years old female patient with Braimbridge type I congenital BEF. We performed division of BEF using stapler and pericardial patch coverage of esophageal side with concomittent left lower lobectomy. This patient was complicated with postoperative esophageal leakage with empyema thoracis. We have successfully managed these problems with re-thoracotomy and re-closure of esophageal fistula using Right Gastroepiploic Artery based pedicled omental flap wrapping around the esophageal anastomosis site. It is felt that pedicled omental flap is a very effective method to manage esophageal complication such as postoperative esophageal leakage.

• Journal of Electrochemical Science and Technology
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• v.3 no.4
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• pp.165-171
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• 2012

An experimental study of mass transfer to an amalgamated copper rotating disc electrode has been employed to determine an empirical correlation for the mass transfer rate in laminar flow. The study was performed in a three-electrodes configuration using 0.1 M boric acid and 0.1M potassium chloride as supporting electrolyte with Zn (II) concentration in the range (25-100 mg $dm^{-3}$). Polarization curves at different zinc ion concentration are reported. Hydrogen and oxygen reduction has also been considered.The diffusion coefficients and mass transfer coefficient were obtained using limiting diffusion current technique based on zinc ion reduction. A least squares analysis indicates that the laminar flow results for 13067 < Re > 57552 and 550 < Sc > 1390 can be correlated by the following equation with correlation coefficient (CR) equal to 0.98: $sh=0.61Re^{0.5}Sc^{1/3}$.