• Transactions on Electrical and Electronic Materials
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• v.6 no.4
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• pp.159-163
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• 2005

We analyzed the fault current limiting characteristics of a flux-lock type $high-T_c$ super­conducting fault current limiter (HTSC-FCL) using series resonance between capacitor for series resonance and magnetic field coil which was installed in coil 3. The capacitor for the series resonance in the flux-lock type HTSC-FCL was inserted in series with the magnetic field coil to apply enough magnetic field into HTSC element, which resulted in higher resistance of HTSC element. However, the impedance of the flux lock type HTSC-FCL has started to decrease since the current of coil 3 exceeded one of coil 2 after a fault accident. The decrease in the impedance of the FCL causes the line current to increase and, if continues, the capacitor for the series resonance to be destructed. To avoid this operation, the flux-lock type HTSC-FCL requires an additional device such as fault current interrupter or control circuit for magnetic field. From the experimental results, we investigated the parameter range where the operation as mentioned above for the designed flux-lock type HTSC-FCL using series resonance occurred.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.2
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• pp.44-48
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• 2004

A silent type ozone generator using water surface electrode was proposed. And it was investigated experimentally that a variation of water conductivity affected to water surface discharge. Important factors affecting to water surface discharge are ions in discharge space and ions and polarized molecules in water and so on. In this study, It was intended to change the characteristics of discharge by controlling the number of ions in water. The number of ions in water could be controlled by changing the water conductivity. Water conductivity was controlled by quantity of inserted NaCl to distilled water. At this time, current-voltage characteristics and characteristics of ozone generation quantity were investigated in each case. As a result, when NaCl was inserted in distilled water, more stable discharge was generated. As the quantity of NaCl was increased, discharge starting voltage could be lowered.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.1
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• pp.39-47
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• 2005

The purpose of this study is to review the prognosis of the TG Osseotite implant(3i Co, USA) placed in partial edentulous area of oral cavity and to suspect the possible causes leading to failure. 124 TG Osseotite implants that had been inserted between 2000 - 2002 were followed up for 2 years(avg : 9.5 months) in function. Medical records, and radiographs were evaluated and analyzed by the over all success rate, gender and age factor, general disease, implant fixture length and diameter, implant site, bone density, and various surgical methods. Chi square test was used statistically. Of the 124 TG Osseotite implants, 9 implants(7.3%) were removed in early phase and 3 implants(2.4%) were in late phase. The cumulative survival rate was 90.2%. The failure of the TG Osseotite implant was closely related with the use of bone graft techniques such as sinus elevation or immediate implantation and not with the age, sex, general disease, implant site, bone density of implanted site. The failure of the TG Osseotite implant was well developed when it was the wide type of implant and it was inserted for single tooth replacement. The developement of peri-implantitis was the most important factor in the failure of the TG Osseotite implant.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.10
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• pp.1103-1108
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• 2010

This paper proposes a new type of PIFA with a capacitor structure inserted into the feeding loop. It operates in GSM900, DCS, PCS, and W-CDMA frequency bands. By inserting the capacitor, it shows the effect of lowering the return loss from -2.73 dB to -6.26 dB at the parallel frequency, 2.01 GHz. The improvement of the poor radiation property near the parallel resonance frequency leads to a broadband operation in the upper band, DCS, PCS, and W-CDMA.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.6
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• pp.619-627
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• 2004

Statement of problem. Mechanisms of tissue-implant interaction and the effect of the implant surface on the behavior of cells has not yet been clarified. Purpose. This study was performed to investigate the tissue reaction to the titanium alloy submerged into rat peritoneum in vivo. Materials and methods. Titanium alloys (titanium-13Zirconium-6Niobium) were inserted inside the peritoneal cavity of Sprague Dawley rats. After 3 months, the tissue formed around the inserted titanium alloys were examined with a light-microscope. Tissue reaction around the material was analyzed by confocal microscopy to evaluate their biocompatibility in a living body. Results. In in vivo study, foreign body type multinucleated giant cells were found in the fibrous tissue formed as a reaction to the foreign material (4 in 20 cases), but the inflammatory reaction was very weak. After experiment, the contaminants of biomaterials was removed from living tissue. In confocal microscopy, we observed that the staining of vinculin and actin showed mixed appearance. In a few cases, we found that the staining of vinculin and beta-catenin showed the prominent appearance. Conclusion. We found that titanium-13Zirconium-6Niobium alloy was an excellent biomaterial.

• Journal of the Korean Institute of Navigation
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• v.19 no.2
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• pp.107-113
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• 1995

Since the most of the mal-functions in the industrial equipments controlled by processors have been occured by the Electrical Fast Transient(EFT), the International Electrotechnical Commision(IEC) prepare the dummy signal to test the immunity level of the equipments controlled by processors and recommend it for the measuring. In this paper, the defined dummy EFT signal by IEC are analyzed by the spectrum analyzer in the frequency domain and studied the developed countermeasuring parts. The new developed parts are consist of the feedthrough capacitors ( $C_y$ type ) in the input and materials with high permeaility which was wound or inserted in the second layer of the Power Cable in order to increase Common Mode inductance. And it is compared inserted Permalloy to material with high permeability increasing Common Mode inductance. We could gotten a excellent insertion loss on the wide band against EFT signal. Especially, we confirm that countermeasuring Power Cable have been an excellent dynamic characteristics in computer system above the 3.6Kv. This new parts could be effectively used for industrial, MIL, and medical equipments to reduce a mal-functions on the site. Furthermore, these parts also have a good characteristics for EMI countermeasuring over the 60MHz up to several GHz band, they are also expected to be used for all kind of EMS test with IEC801-2, 3, 5 and 6 on the power distributed line.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.2
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• pp.91-96
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• 2010

The combination of a bolt and nut is the element most widely used for connecting machines and structures. When a load is repetitively applied in the direction right angle to the bolt axis after the bolt and nut is fastened, the nut gradually becomes loose. To solve this problem, in this study, a new type of the loose-proof nut, called a lock nut, is developed. The lock nut is equipped with a spring, and the spring increases the axial force of the bolt. Then, the connection force between the bolt and nut is also augmented. Three dimensional finite element models for the bolt and spring are generated, and the change of the axial force of the bolt while the bolt is being inserted into the spring is analyzed using MSC/Marc, a commercial finite element program. Finally, the optimum shape of the spring is found according to the response surface analysis methodology. The optimization result is verified by comparing the variation of the axial force of the bolt when the bolt is inserted to the initial and optimized spring.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.10
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• pp.21-29
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• 1999

This paper is concerning about the demapping method using the pilots inserted in transmitter in COFDM(Coded Orthogonal Frequency Division Multiplexing) demodulator which is the standard transmission method of terrestrial digital TV system in Europe(DVB-T). We have presented a simple and efficient method of CSI(Channel State Information) generation and demapping method using CSI. The CSI was derived from the pilot carriers inserted with comb-type among the received active carriers, which is defined as a SNR. From the simulation results for the 3 different constellations of the receiver, we could confirm that the system performance comparing with conventional soft decision method has been improved under DVB-T standard Rayleigh and Ricean fading channel.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1853-1855
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• 2000

An experimental investigation has been performed in order to understand the $\Phi$-q-n characteristics related to the PD taking place from the various size of artificial defects inserted in epoxy insulation. In this purpose, PD has been detected simultaneously by two different methods such as commercialized PD detector(TE571) and our detection system using self designed CT type sensor. Under the presence of void in epoxy insulation, PD has been initiated at the voltages between 16kV and 20kV which are much lower than the dielectric strength of epoxy insulation (130kV/mm$\sim$l50kV/mm). And also it is revealed that $\Phi$-q-n characteristics have been observed to be dependent upon the size of the artificial defects. Throughout this work, the on site applicability of the self designed Sensor has also been proved by comparing the results with those from the commercialized PD detector. And more one, considerable basic data regarding the insulation, diagnosis could be provided to understand the presence of the voids possibly inserted into the epoxy insulation system of the power apparatus.

• Journal of Embryo Transfer
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• v.30 no.3
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• pp.171-174
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• 2015

Four pluriparous Korean black goat does were superovulated with FSH and mated with fertile bucks. Anesthetized animals were placed in lateral recumbency, then size 8 Foley catheter was inserted into the uterus through the cervix under the vaginal speculum and the balloon was inflated to fix the catheter in the uterine body. The opposite end of the catheter was connected to a 3-way and a flushing medium was infused into the uterus. Modified Dubecco's PBS with 1% FBS was used as the flushing medium. Four goats were allocated in two groups depending on the type of medium infusion into uterus. Injection group; the flushing medium was injected into uterus and the infused medium was collected by to-and-fro method using a syringe. Gravity-flow group; the flushing medium was allowed to enter the uterus by gravity flow by lifting the medium bottle and drained out of the uterus into a collecting tube. All four goats had catheter inserted through the cervix and uteri flushed successfully. The volume (recovery rate) of recovered medium varied considerably from 87 ml/200 ml (43.5%) to 148 ml/160 ml (92.5%). Nine embryos/ova in total were recovered from Gravity-flow group goats. Although the embryo recovery rate was low, the possibility of a transcervical embryo recovery in Korean black goat had been proven in this preliminary experiment.