• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.17-18
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• 2007

Solid oxide fuel cells are clean, pollution-free technology for the electrochemical generation of electricity at high efficiency. Specially, the polarization resistance between electrolyte and electrode of SOFC unit cell is of importance, because it is desirable to develop SOFC operating at intermediate temperature below $800^{\circ}C$. The LSCF cathode prepared using modified oxalate method was investigated with different electrolyte. A precursor was prepared with oxalic acid, ethanol and $NH_4OH$ solution. The LSCF precursor was prepared at $80^{\circ}C$, and pH control was 2, 6, 8, 9 and 10. The precursor powder was calcined at $800^{\circ}C$, $1000^{\circ}C$ and $1200^{\circ}C$ for 4hrs. The crystal of LSCF powders show single phase at pH 2, 6, 8 and 9, and the average particle size was about $3{\mu}m$. The LSCF cathode with heat treatment at $1200^{\circ}C$ showed a plot of electric conductivity versus temperature. Unit cell prepared from the LSCF cathode, buffer layer between cathode and electrolyte and the LSGM, YSZ, ScSZ and CeSZ electrolyte. Also interface reaction between LSCF, buffer layer and electrolyte were measured by EPMA and the polarization resistance for unit cell with cycle measure using a Solatron 1260 analyzer.

• Radiation Oncology Journal
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• v.35 no.1
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• pp.32-38
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• 2017

Purpose: Several accelerated partial breast radiation (APBR) techniques have been investigated in patients with early-stage breast cancer (BC); however, the optimal treatment delivery techniques remain unclear. We evaluated the feasibility and toxicity of APBR delivered using intensity-modulated radiation therapy (IMRT) in elderly patients with stage I BC, using a novel fractionation schedule. Materials and Methods: Forty-two patients aged ${\geq}65$ years, with stage I BC who underwent breast conserving surgery were enrolled in a phase I/II study evaluating APBR using IMRT. Forty eligible patients received 40 Gy in 4 Gy daily fractions. Patients were assessed for treatment related toxicities, and cosmesis, before APBR, during, and after completion of the treatment. Results: The median age was 73 years, median tumor size 0.8 cm and the median follow-up was 54 months. The 5-year locoregional control was 97.5% and overall survival 90%. Erythema and skin pigmentation was the most common acute adverse event, reported by 27 patients (69%). Twenty-six patients (65%) reported mild pain, rated 1-4/10. This improved at last follow-up to only 2 (15%). Overall the patient and physician reported worst late toxicities were lower than the baseline and at last follow-up, patients and physicians rated cosmesis as excellent/good in 93% and 86 %, respectively. Conclusion: In this prospective trial, we observed an excellent rate of tumor control with daily APBR. The acceptable toxicity profile and cosmetic results of this study support the use of IMRT planned APBR with daily schedule in elderly patients with early stage BC.

• Natural Product Sciences
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• v.8 no.2
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• pp.44-47
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• 2002

The effects of Eurycoma longifolia Jack on masculine copulatory behaviour were studied in the middle aged male Sprague-Dawley rats, 9 months old and retired breeders after dosing them with 500 mg/kg twice daily for 10 days prior to test. The test lasted for 30 minutes after a 20 minute adaptation period, was carried out on the 11th day during the dark phase of the light-dark cycle (2000-0700 hours) and in subdued light, using a modified copulation cage but with the presence of a piece of mirror of appropriate size to facilitate observation. Results showed that the mean values of EL-1, EL-2 and EL-3 of the control middle aged male rats were 103.20 sec, 91.21 sec and 80.00 sec but were significantly (p<0.05) increased to 118.40-120.20 sec, 101.24-171.28 sec and 100.42-110.21 sec respectively in the methanol-chloroform, methanol-butanol-water and methanol-butanol treated middle aged male rats. However, further results also showed that PEI-1 and PEI-2 of the control middle aged male rats were 182.30 sec and 257.2 sec but were significantly (p<0.05) decreased to 100.42-121.31 sec and 40.21-132.31 sec respectively in the methanol-chloroform-butanol-water and methanol-butanol treated middle aged male rats. In conclusion, this study showed that although E. longifolia Jack continued to enhance the sexual activity of the middle aged male rats by extending the duration of coitus and decreasing the refractory period between the different series of copulation, but to a smaller degree as compared to sexually active, adult male rats (Ang and Sim, 1997).

• Clinical and Experimental Reproductive Medicine
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• v.20 no.1
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• pp.37-43
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• 1993

In 27 patients with the past history of poor response to the gonadotropin superovulation induction due to poor follicular growth or permature surge of endogenous luteinizing hormone, the effectiveness of pituitary supperssion with the gonadotropin releasing hormone agonist(GnRH-a) in in vitro fertilization(IVF) program was evaluated in 43 cycles using a combination regimen of D-Trp-6 LHRH(Decapeptyl, Ferring)and FSH/hMG from June, 1989 to August, 1990 at Korea University Hospital IVF Clinic. At midluteal phase of menstrual cycle, Decapeptyl-CR was administered by long-term protocol to minimize initial agonistic effect of endogenous gonadotropins. After the confirmation of pituitary suppression, about 2-3 weeks after GNRH-a administration, ovarian follicle growth was stimulated with FSH/hMG and followed by transvaginal ultrasonic measurement of follicle size and by monitoring of serm E2 and LH if necessary. When compared with the control group stimulated with gonadotropin regimen only, the cancellation rate and occurrence rate of premature LH surge during gonadotropin treatment were significantly lower in study group(11.6% and 2.4%, respectively). There is no significant differences in the mean number of aspirated oocytes, fertilization/cleavage rate, embryo transfer(ET) rate, and mean number of embryos transferred between the two groups. The pregnancy rate per treatment cycle, 16.3%, and per ET cycle, 23.3%, were significantly higher in the study group compared with those of control group. These data suggest that GnRH-a therapy is effective for previous poor responder In gonadotropin superovulation induction for IVF.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.12
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• pp.1284-1289
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• 2014

In this Paper, outdoor position estimation system was implemented using GPS (Global Positioning System) and INS (Inertial Navigation System). GPS position information has lots of errors by interference from obstacles and weather, the surrounding environment. To reduce these errors, multiple GPS system is used. Also, the Discrete Wavelet Transforms was applied to INS data for compensation of its error. In this paper, position estimation of the mobile robot in the straight line is conducted by EKF (Extended Kalman Filter). However, curve running position estimation is less accurate than straight line due to phase change in rotation. The curve is recognized through the rate of change in heading angle and the position estimation precision of the initial curve was improved by UPF (Unscented Particle Filter). In the case of UPF, if the number of particle is so many that big memory gets size is needed and processing speed becomes late. So, it only used the position estimation in the initial curve. Thereafter, the position of mobile robot in curve is estimated through switching from UPF to EKF again. Through the experiments, we verify the superiority of the system and make a conclusion.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.759-764
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• 2018

3D porous carbon electrodes (cNPIM), prepared by solution casting of a polymer of intrinsic microporosity (PIM-1) followed by nonsolvent-induced phase separation (NIPS) and carbonization are presented. In order to effectively control the pore size of 3D porous carbon structures, cNPIM was prepared by varying the THF ratio of mixed solvents. The SEM analysis revealed that cNPIMs have a unique 3D macroporous structure having a gradient pore structure, which is expected to grant a smooth and easy ion transfer capability as an electrode material. In addition, the cNPIMs presented a very large specific surface area ($2,101.1m^2/g$) with a narrow micropore size distribution (0.75 nm). Consequently, the cNPIM exhibits a high specific capacitance (304.8 F/g) and superior rate capability of 77% in an aqueous electrolyte. We believe that our approach can provide a variety of new 3D porous carbon materials for the application to an electrochemical energy storage.

• Radiation Oncology Journal
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• v.35 no.4
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• pp.325-331
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• 2017

Purpose: There is controversy regarding the cosmetic outcome after accelerated partial breast radiation (APBR). We report the cosmetic outcome from a single-arm prospective clinical trial of APBR delivered using intensity-modulated radiation therapy (IMRT) in elderly patients with stage I breast cancer (BC), using a novel fractionation schedule. Materials and Methods: Forty-two patients aged ${\geq}65$, with Stage I BC who underwent breast-conserving surgery were enrolled in a phase I/II study evaluating a 2-week course of APBR. Thirty eligible patients received 40 Gy in 4 Gy daily fractions. Cosmetic outcome was assessed subjectively by physician/patient and objectively by using a computer program (BCCT.core) before APBR, during, and after completion of the treatment. Results: The median age was 72 years, the median tumor size was 0.8 cm, and the median follow-up was 50.5 months. The 5-year locoregional control in this cohort was 97% and overall survival 87%. At the last follow-up, patients and physicians rated cosmesis as 'excellent' or 'good' in 100% and 91 %, respectively. The BCCT.core program scored the cosmesis as 'excellent' or 'good' in 87% of the patients at baseline and 81% at the last follow-up. The median $V_{50}$ (20 Gy) of the whole breast volume (WBV) was 37.2%, with the median WBV $V_{100}$ (40 Gy) of 10.9%. Conclusion: An excellent rate of tumor control was observed in this prospective trial. By using multiple assessment techniques, we are showing acceptable cosmesis, supporting the use of IMRT planned APBR with daily schedule in elderly patients with early stage BC.

• Journal of the Korean Ceramic Society
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• v.50 no.5
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• pp.333-340
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• 2013

To fabricate spherical lithium titanate ($Li_2TiO_3$) pebbles which are used for a breeder material in fusion reactor, titanium oxide ($TiO_2$) granules were used as a starting material. The granules were pre-sintered, and then aqueous lithium nitrate solution infiltrated into the granules at vacuum condition. The granules were crystallized to $Li_2TiO_3$ after sintering under the control of process parameters. In this study, the concentration of lithium in the solution, as well as the number of penetration times and sintering temperature affected the final crystallite phase and the microstructure of the pebbles. In particular, the sphericity and size of the pebbles were effectively controlled by a technical rolling process. The useful spherical $Li_2TiO_3$ pebbles which have 10~20% porosity and 60~120 N compressive strength were obtained through the sintering at $1000{\sim}1100^{\circ}C$ in the multi-times infiltration process with 50 wt% solution. The physical properties of pebbles such as density, porosity and strength, can be controlled by a selection of $TiO_2$ powders and control of processing parameters. It can be thought that the lithium penetration method is a useful method for the fabrication of mass product of spherical $Li_2TiO_3$ pebbles.

• Journal of IKEEE
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• v.17 no.2
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• pp.135-139
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• 2013

This paper presents the 8-channel active module operated in Ka-band. The module is designed for the mobile satellite communication antenna systems, and the module structure has the merit to minimize the size and weight of the antenna systems by 30% compared with the conventional systems using the active module composed of single channel. This module was designed to be optimally operated by prohibiting the electrical interference among the individual channels. From the test results of the fabricated 8-channel active module, it can be confirmed that the maximum channel gain error is ${\pm}1.3dB$, the minimum channel output power is 21.5dBm, and the maximum gain variation by phase control is ${\pm}1.0dB$.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.31 no.1
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• pp.22-31
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• 2018

Objectives : In this study, we investigated whether Astragali Radix Pharmacocupuncture (ARP) has an effective on the full thickness defect wound healing process of mouse. Methods : A total of 50 mice (ICR mouse, 7 week-old male) were divided into control group and ARP group. A single full thickness skin defect was made on the dorsal side of the each mouse using an 8mm diameter biopsy punch. Control group were treated with 0.2㎖ saline and ARP group were treat with 0.2ml ARP at 8 points around the wound every three days total 4 times during the experimental period. The change in wound size, contraction rate, healing rate, and epithelization rate was measured by digital images taken on days 3, 6, 9, and 13, and evaluated using a digital image analysis program. Tissues were collected for histological analysis, RT-PCR, and Western blot on days 3, 6, 9, and 15. Results : The results are as follows. ARP group accelerated the rate of wound contraction, wound healing and epithelization compared to the control group. ARP group showed the decrease of inflammatory cells in early inflammatory phase compared to the control group. ARP group upregulated PECAM-1 mRNA and protein expression compared to the control group. ARP group inhibited the scar width and area compared to the control group. Conclusions: ARP showed positive effects on wound healing through the inhibition of inflammatory reaction and increase of PECAM-1 expression related to the wound healing process.