• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.7
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• pp.1417-1426
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• 2011

Radiofrequency ablation through cardiac catheterization is one of minimally invasive intervention procedures used in drug resistant arrhythmia treatment. To facilitate more accurate and precise catheter navigation, systems for robotic cardiac catheter navigation have been developed and commercialized. The authors have been developing a novel robotic catheter navigation system. The system is a network-based master-slave configuration 3-DOF (Degree-Of-Freedom) robotic manipulator for operation with conventional cardiac ablation catheter. The catheter manipulation motion is composed of the translation (forward/backward) and the roll movements of the catheter and knob rotation for the catheter tip articulation. The master manipulator comprises an operator handle compartment for the knob and the roll movement input, and a base platform for the translation movement input. The slave manipulator implements a robotic catheter platform in which conventional cardiac catheter is mounted and the 3-DOF motions of the catheter are controlled. The system software that runs on a realtime OS based PC, implements the master-slave motion synchronization control in the robot system. The master-slave motion synchronization performance tested with step, sinusoidal and arbitrarily varying motion commands showed satisfactory results with acceptable level of steady state error. The developed system will be further improved through evaluation of safety and performance in in vitro and in vivo tests.

• The Korean Journal of Pain
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• v.20 no.1
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• pp.60-65
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• 2007

Complex Regional Pain Syndromes (CRPS) type I and type II are neuropathic pain conditions that are being increasingly recognized in children and adolescents. The special distinctive features of pediatric CRPS are the milder course, the better response to treatment and the higher recurrence rate than that of adults and the lower extremity is commonly affected. We report here on a case of pediatric CRPS that was derived from ankle trauma and long term splint application at the left ankle. The final diagnoses were CRPS type I in the right upper limb, CRPS type II in the left lower limb and unclassified neuropathy in the head, neck and precordium. The results of various treatments such as medication, physical therapy and nerve blocks, including lumbar sympathetic ganglion blocks, were not effective, so implantation of a spinal cord stimulator was performed. In order to control the pain in his left lower limb, one electrode tip was located at the 7th thoracic vertebral level and two electrode tips were located at the 7th and 2nd cervical vertebral levels for pain control in right upper limb, head, neck and right precordium. After the permanent insertion of the stimulator, the patient's pain was significantly resolved and his disabilities were restored without recurrence. The patient's pain worsened irregularly, which might have been caused by psychological stress. But the patient has been treated with medicine at our pain clinic and he is being followed up by a psychiatrist. (Korean J Pain 2007; 20: 60-65)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.167-172
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• 1986

This experiment was carried out to obtain some information about the growth habit and morphological and anatomical characteristics of fasciated soybean, var. Buchai-kong. The results obtained are summarized as follows: 1. Main stern of fasciated soybean, var. Buchai-kong was gradually broadened and became flat, on which leaves emerged irregularly compared with normal soybean, var. Danyeop-kong. The number of leaves on main stern was more in Buchai-kong, but the total number of leaves per plant was not considerably different each other. 2. The degree of fasciation (max./min. in diameter at the broadened part) in main stern of Buchai-kong was about 3.1, and was related to the amount of growth of main stern and branches of Danyeop-kong. Stern fasciation types found in Buchai-kong were linear (the most common) and bifurcated with regard to branching of main stern tip. 3. The number of branches per plant was much less in Buchai-kong than in Danyeop-kong. There were fas-ciated branches and fasciated petiole in Buchai-kong. 4. About 75 percent of pods of Buchai-kong were concentrated on the top of stern, which showed strong pod clustering. 5. Seed yield per plant of Buchai-kong was about 60 percent of that of Danyeop-kong, and the decrease in seed yield was mostly affected by the decrease in seed weight and seeds per pod. 6. The number of vascular bundles of transection of mature stern was more in Buchai-kong, but Danyeop-kong developed the better vascular bundle.

• Clinics in Shoulder and Elbow
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• v.24 no.2
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• pp.66-71
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• 2021

Background: Extra-articular distal humerus locking plates (EADHPs) are precontoured anatomical plates widely used to repair distal humeral extra-articular diaphyseal fractures. However, EADHPs frequently cause distal protrusion and resulting skin discomfort. The purpose of this study was to predict the occurrence of anatomic fit mismatch. We hypothesized that the smaller the humerus size, the greater the anatomic fit mismatch with EADHP. Methods: Twenty humeri were analyzed in this study. Humeral length and distal humeral width were used as parameters of humeral size. Plate protrusion was measured between the EADHP distal tip and the distal humerus. We set the level of unacceptable EADHP anatomic fit mismatch as ≥10 mm plate protrusion. Results: A significant negative linear correlation was also confirmed between humeral size and plate protrusion, with a coefficient of determination of 0.477 for humeral length and 0.814 for distal humeral width. The cutoff value of humeral length to avoid ≥10 mm plate protrusion was 293.6 mm (sensitivity, 88.9%; specificity, 81.8%) and for distal humeral width was 60.5 mm (sensitivity, 100%; specificity, 81.8%). Conclusions: Anatomic fit mismatch in distal humeral fractures after EADHP fixation has a negative linear correlation with humeral length and distal humeral width. For patients with a distal humeral width <60.5 mm, ≥10 mm plate protrusion will occur when an EADHP is used, and an alternative implant or approach should be considered.

• Journal of Plant Biotechnology
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• v.48 no.2
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• pp.86-92
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• 2021

The present study aimed to evaluate the initiation, proliferation potential, and mass clonal production ability of a micropropagation system for banana through tissue culture. A total of 60 explants were cultured on basal media supplemented with various concentrations of BAP and NAA. Banana plants regenerated on MS basal medium (control) without the addition of BAP + NAA showed a significantly (P < 0.05) lower survival rate with no signs of shoots up to the end of the experimental period. The results further revealed that the performance in MSS-XI medium was almost 89%, followed by MSS-IX and MSS-X media, both of which showed performance up to 88%. In contrast, the performance in the MSS-XVI medium was less than 60%, at the less duration of time and highly shoot induction detected at MSS-XIII medium. The maximum number of shoots (4.9) was observed in the medium supplemented with growth adjuster MSS-XI, followed by the MSS-XII medium (4.5). Surprisingly, the best performance was observed for the MSR-VII medium approximately 16 days after initiation, while the lowest performance was observed with MSR-XI (approximately 31 days). The maximum rooting percentage (98%) was observed in the MSR-V to MSR-VIII media (98%), while the minimum rooting percentage was observed in MSR-XI (approximately 45%).

• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.231-239
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• 2023

In order to improve the propeller Cavitation Inception Speed (CIS) performance, it needs to modify the propeller geometry and the wake distribution that flows into the propeller. In the previous study, the twisted angles of the V-strut were modified to improve propeller CIS, cavitation behavior and pressure fluctuation performances. Then the propeller behind the modified V-strut (New strut) showed better cavitation characteristics than that behind the existing V-strut (Old strut). However, the CIS of Suction Side Tip Vortex (SSTV) and Pressure Side Tp Vortex (PSTV) showed a big difference at behind each V-strut. In this study, the balance design is conducted to minimize the difference between SSTV CIS and PSTV CIS at behind each V-strut. To improve the propeller CIS performance, 1 propeller is designed at behind the old strut and 3 propellers are designed at behind the new strut. The propeller CIS is increased through the balance design and the stern appendage modification. The final propeller CIS is increased about 5.3 knots higher than that of the existing propeller at behind the old strut. On the basis of the present study, it is thought that the better improvement method for the propeller CIS would be suggested.

• Korean Journal of Ichthyology
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• v.35 no.1
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• pp.1-9
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• 2023

The morphological development of larvae and juvenile of Sebastes taczanowskii were studied. The S. taczanowskii were caught at Goseong-gun, Gangwon-do from March in 2016. Larvae beared at water temperature of 11~12℃ (mean 11.5±0.5℃). The just beared larvae were 5.25~5.96 mm (mean 5.60±0.19 mm, n=30) in total length and their mouth and anus were already opened. They began to eat rotifer and transformed to postlarvae stage. 35 days after bearing postlarvae was measured 7.16~11.4 mm (mean 9.02±1.00 mm) in total length and the tip of notochord was bent upward. 48 days after bearing juvenile was measured 9.45~18.7 mm (mean 14.4±1.75 mm) in total length with dorsal fin rays XIII, 13~15; anal fin rays III, 6~8; caudal fin rays 16.

• International Journal of Automotive Technology
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• v.7 no.4
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• pp.407-413
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• 2006

The liquefied petroleum gas(LPG), mixture of propane and butane, has the potential to reduce toxic hydrocarbon emissions and inhibit ozone formation due to its chemical composition. Conventional mixer systems, however, have problems in meeting the future lower emission standards because of the difficulty in controlling air-fuel ratio precisely according to mileage tar accumulation. Liquid Phase LPG injection(LPLi) system has several advantages in more precise fuel metering and higher engine performance than those of the conventional mixer type. On the other hands, leakage problem of LPLi system at the injector tip is a main obstacle for meeting more stringent future emission regulations because these phenomena might cause excessive amount of THC emission during cold and hot restart phase. The main focus of this paper is the development of a leaked fuel recirculation system, which can eliminate the leaked fuel at the intake system with the activated carbon canister. Leaked fuel level was evaluated by using a fast response THC analyzer and gas chromatography. The result shows that THC concentration during cold and hot restart stage decreases by over 60%, and recirculation system is an effective method to meet the SULEV standard of the LPLi engine.

• Journal of Oral Medicine and Pain
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• v.3 no.1
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• pp.11-22
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• 1977

In order to evaluate the normal eruption time of the Korean permanennt teeth, the author had examined the eruption phases of permanent first molars in 778 males and 653 female children aged from 5 to 9-year old and analysed. The eruption was divided into 4 phases; the tip of the crown can be seen, the dull occlusal surface of the crown can be easily seen, the crown is not in contact with its antagonist, and the crown is in contact with its antagonist. The obtained results were as follows : 1. It seemed that percentage of the eruptingand erupted permanent first molar in female by age was higher than that of male. 2. In general, percentage of the erupting and erupted permanent first molar by age was higher than that of upper first molar. 3. In the correlation of age with the eruption phase, the regression equation were "y=0.43x+5.61" on male upper first molar, "y=0.41x+5.60" on male lower first molar, "y=0.44x+5.47" on female upper first molar, and "y=0.38x+5.57" on female lower first molar respectively.n female lower first molar respectively.

• The KSFM Journal of Fluid Machinery
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• v.17 no.5
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• pp.60-66
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• 2014

Most tidal current turbine designs are focused on medium and large scale for deep sea, less attention is paid in low water level channel, such as the region around the islands and costal sea. This study is to develop a horizontal axis tidal current turbine rotor blade which is applicable to low water level island region in southwest coastal region of Korea. In this study, the hydrofoil NACA63-415 and NACA63-817 are both adopted to analyze. The blade using NACA63-817 showed the higher maximum power coefficient and good performance at small TSR (Tip Speed Ratio), which gives the blade more advantages in operating at lower water level channel, where is characterized by the fast-flowing water. The cavitation pattern of hydrofoil is predicted by the CFD analysis and verified that the NACA63-817 is the appropriate hydrofoil in the test site of tidal current resource and the hydrofoil showed considerable performance in avoiding cavitation.