• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.642-647
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• 2006

Yeast selection and the sterilization methods of strawberry juice were optimized for making strawberry wine. In addition, changes in the physicochemical characteristics of the wine during its fermentation were estimated. Maehyang and Yukbo cultivars of strawberry were tested for wine making; they contained 9.8 and 9.3% soluble solids and 0.59 and 0.58% titratable acidities, respectively. Among six yeasts tested, the Wg-15 and Sc-51 strains were selected based on the alcohol yield in the strawberry wine. Alcohol and soluble solid contents following heat treatment ($85^{\circ}C$, 10 min) or $K_2S_2O_5$ (200 ppm) treatment for sterilization were 7.10-7.20% and 5.60-5.80%, respectively, and no differences were observed between the Wg-15 and the Sc-51 strains. However, the flavor of wine produced following heat treatment was slightly better than that following $K_2S_2O_5$ treatment. The greatest amounts of alcohol were produced after 2 days of fermentation at $26^{\circ}C$. The alcohol content in wines produced with 12, 14, and 16% sugar content in the initial stages were 5.1, 6.0-6.2, and 7.5-7.7%, and the soluble solid contents were 3.9-4.3, 4.1-4.3, and 5.0-5.3%, respectively; no significant differences were observed between the Wg-15 and the Sc-51 yeast strains. For making strawberry wine, we proposed that the sugar content of Maehyang or Yukbo cultivars be adjusted to 16% soluble solids in the initial stages with heat treated at $85^{\circ}C$ for 10 min and fermentation with the Wg-15 or Sc-51 yeast strains at $26^{\circ}C$ for 8 days.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.210-211
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• 2006

A series of L-LA polymerizations initiated by $Sn(Oct)_{2}\;([LA]_{0}/[Sn]_{0}=200)$ were carried out in scR22 at $130^{\circ}C$ and 300 bar, where $[LA]_{0}$ is the initial L-lactide concentration and $[Sn]_{0}$ is the initial $Sn(Oct)_{2}$ concentration. The reaction time dependences of monomer conversion and PLLA MW improved. The monomer conversion and PLLA MW increased with increasing reaction time. The effect of temperature on monomer conversion and PLLA MW was investigated in a series of polymerizations conducted at temperatures ranging from 90 to $150^{\circ}C$ and at a constant pressure of 200 bar. In all of these experiments, the ratio of monomer to R22 concentration was held constant at 12.4 wt.-%. Increasing the reaction temperature from 90 to $130^{\circ}C$ resulted in increased monomer conversion from 11.5 to 72.2 %.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4984-4990
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• 2010

In this paper, a Step-down CMOS DC-DC Converter using low power switched capacitor method is designed in a 0.5 ${\mu}m$ technology for the integration of devices. Conventional DC-DC converter is used inductor that can store energy in a magnetic field but have low efficiency because power consumption is caused by magnetic flux. And there were problems with size, weight and price to integrate chip. In this paper, a proposed Inductorless step-down CMOS DC-DC converter of low power using SC method is designed in a 0.5um technology to solve these problems. Designed DC-DC converter have 96% power efficiency with 200kHz frequency by using cadence simulation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.6
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• pp.374-379
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• 2007

Two experiments were designed to examine short-term effects of human chorionic gonadotropin (hCG), and long-term effects of gonadotropin-releasing hormone agonist (GnRHa), $17{\alpha}-hydroxyprogesterone$ (17P), and $17{\alpha},20{\beta}-dihydroxy-4-pregnen-3-one\;(17,20{\beta}P)$, alone or in combination, on milt production of the starry flounder Platichthys stellatus. In the first experiment, fish were injected with either 200 IU hCG/kg body weight or the same volume of marine fish Ringer's solution (MFRS). In the second experiment, each fish was implanted with a blank cholesterol pellet (control), $200\;{\mu}g$ GnRHa, $500\;{\mu}g$ 17P, or $100\;{\mu}g\;17,20{\beta}P/kg$ body weight alone or in combination. In the first experiment, hCG injection resulted in an increase in the expressible milt volume and a decrease in the spermatocrit (Sct). After pellet implantation in the second experiment, the milt volume was increased in males treated with GnRHa, GnRHa+17P, or $GnRHa+17,20{\beta}P$. On day 7 after hormone pellet implantation, the milt volume began to increase, and on day 14, the milt volume in the $GnRHa+500\;{\mu}g$ 17P group was significantly higher than that in the control group. Compared with the control group, the hormone pellet-treated groups had a significant reduction in the mean Sct and sperm concentration (Sc) at day 7 after pellet implantation, while there were no differences in total sperm number. The results suggest that increases in milt volume are generally associated with decreases in Sct and SC, suggesting that the main mechanism for the increase in milt volume was milt hydration.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.134-141
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• 2007

This paper presents a frequency synthesizer(FS) for 5.2GHz/2.4GHz dual band wireless applications which is designed in a standard $0.18{\mu}m$ CMOS1P6M process. The 2.4GHz frequency is obtained from the 5.2GHz output frequency of Voltage Controlled Oscillator (VCO) by using the Switched Capacitor (SC) and the divider-by-2. Power dissipations of the proposed FS and VCO are 25mW and 3.6mW, respectively. The tuning range of VCO is 700MHz and the locking time is $4{\mu}s$. The simulated phase noise of PLL is -101.36dBc/Hz at 200kHz offset frequency from 5.0GHz with SCA circuit on.

• The Korean Journal of Financial Management
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• v.23 no.1
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• pp.243-266
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• 2006

This paper tests cross hedging performance of the KOSPI 200 stock index futures to hedge the downside risk of the KOSPI, KOSPI 200 and KOSDAQ50 spot market. For this purpose we introduce the minimum variance hedge model, bivariate GARCH(1,1) and EGARCH(1,1) model as hedge models. The main results are as follows; First, we find that the direct hedge performance of KOSPI 200 index futures is better than those of indirect hedge performance. second, in case or cross hedge performance the hedge effect of KOSPI 200 stock index futures market against KOSPI 200 stock index spot market is relatively better than those of KOSPI 200 index futures against KOSPI and KOSDAQ spot position. Third, for the out-sample, hedging effectiveness of the risk-minimization with constant hedge ratios is higher than those of the time varying bivariate GARCH(1,1) and EGARCH(1,1) model. In conclusion, investors are encouraged to use simple risk-minimization model rather than the time varying hedge models like GARCH and EGARCH model to hedge the position of the Korean stock index cash markets.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.4
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• pp.20-30
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• 2001

A novel 200 MHz CMOS transconductor using translinear cells is proposed. The proposed transconductor consists of voltage followers and current followers based on translinear cells and a resistor. For wide applications, a single-input single-output, a single-Input differential-output, and a fully-differential transconductor are systematically designed, respectively. The theory of operation is described and computer simulation results are used to verify theoretical predictions. The results show that the fully-differential transconductor has a linear input voltage range of ${\pm}2.7$ V, a 3 dB frequency of 200 MHz, and a temperature coefficient of less than 41 $ppm/^{\circ}C$ at supply voltages of ${\pm}3$ V. In order to certify the applicability of the fully-differential transconductor, A ladder-type 3th-order cllitic low pass filter is also designed based on the inductance simulation method. The filter has a ripple bandwidth of 22 MHz, a pass-band ripple of 0.36 dB, and a cutoff frequency of 26 MHz.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.2
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• pp.596-602
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• 2016

Experiments were carried out examine short-term effects of human chorionic gonadotropin (hCG) and long-term effects of luteinising hormone releasing hormone analogue (LHRHa) on milt production of the tongue sole Cynoglossus semilaevis. In the first experiment, each fish was implanted with a blank cholesterol pellet (control), 100 and $200{\mu}g$ LHRHa per kg body weight. In the second experiment, fish were injected with either 100, 200, 400 and 800 IU hCG per kg body weight or same volume of marine fish Ringer's solution. In the first experiment, milt volume was increased in male implanted with $200{\mu}g$ LHRHa pellet compared with other groups at day 10. Injection of 400 and 800 IU hCG resulted in an increase in the milt volume at hour 96 after the treatment. Although statistical difference is unable to confirm because of small milt volume, compared with the control group, hormone pellet-treated groups had a reduction in the mean spermatocrit (Sct) and sperm concentration (Sc). The results suggest that the increase in milt volume is at least partially gonadotropin (GtH)-dependent and increased milt volume has a relationship with milt hydration.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.3
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• pp.83-91
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• 2009

It is very difficult to export the fresh agricultural products to long distance countries such as USA and EU without any damage. Fresh products exporting would overcome very severe conditions such as hot and cold weather changes, heavy vibrations with rolling and pitching during the target distribution period, therefore, the packaging needs the immobility of products in the container and the keeping its quality by packaging materials or methods under any surrounding environments, especially. The physical strength of outer box should be designated according to its own characteristics for agricultural product packaging. Packaging dimension which would be fit to standard pallet is also very important factor to reduce the distribution cost. There have been many agricultural products researches for export packaging to the USA so far. However they have never got desirable results which enough to apply it in real. The main purpose of this research is to develop optimum compressive strength and optimum dimension of corrugated fiberboard box which would be used to USA export packaging of fresh melon as well as Japan.

• Journal of Sasang Constitutional Medicine
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• v.29 no.3
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• pp.242-247
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• 2017

Objective Korean medicine Data Center (KDC) has established large-scale biological and clinical data based on Korean medicine to demonstrate and validate its theory. The aim of this study was to develop KDC teaching dataset and user guideline to improve utilization of the KDC. Method KDC teaching dataset were selected using stratified random sampling according to the Sasang constitution (SC). This dataset included 72 variables of 500 sample subjects. The user guideline described how to conducted eight statistical analysis methods using the teaching dataset. Results The KDC teaching dataset was sampled from 200(40%) Taeeumin, 125(25%) Soeumin, and 175(35%) Soyanain. It was consisted of questionnaire (basic, habit, disease, symptom), physical exam (body measurement, blood pressure), blood exam, and expert' SC diagnosis. The usage guidelines provided instruction for users to perform several statistical analysis step by step with KDC teaching dataset. Conclusion We hope that our results will contribute to enhancing KDC utilization and understanding.