• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.4
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• pp.427-435
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• 2016

The effects of salt solution and chlorella on the quality of canned oyster, Crassostrea gigas, were evaluated to obtain basic data regarding the processing of two canned oyster products. In canned oyster processing, the shucked oyster meat was steamed for 20 min and then drained. Then, each can (301-3) was filled with 90 g boiled oyster in 60 mL 1.5% salt solution for the control samples or 30 mL 1.5% salt solution and 30 mL chlorella culture medium for the experimental samples. All canned products were sealed using a vacuum seamer and then sterilized to Fo values of 6-12 min in a steam retort system at 118℃. The viable bacteria count, proximate composition, pH, salinity, yield, volatile basic nitrogen (VBN), amino-nitrogen, thiobarbituric acid (TBA), mineral, color value, free amino acid levels, hardness, and sensory evaluation of the two canned products were measured under various sterilization conditions. There were no significant differences in the physical or chemical factors and little difference in the overall acceptance of the control and experimental samples.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.567-573
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• 2007

The crystal structure of ZnI2 molecule synthesized in zeolite A (LTA) has been studied by single-crystal X-ray diffraction techniques. A single crystal of |Zn6|[Si12Al12O48]-LTA, synthesized by the dynamic ion-exchange of |Na12|[Si12Al12O48]-LTA with aqueous 0.05 M Zn(NO3)2 and washed with deionized water, was placed in a stream of flowing 0.05 M KI in CH3OH at 294 K for four days. The resulting crystal structure of the product (|K6Zn3(KI)3(ZnI2)0.5|[Si12Al12O48]-LTA, a = 12.1690(10) A) was determined at 294 K by single-crystal X-ray diffraction in the space group Pm3m. It was refined with all measured reflections to the final error index R1 = 0.078 for 431 reflections which Fo > 4σ (Fo). At four crystallographically distinct positions, 3.5 Zn2+ and nine K+ ions per unit cell are found: three Zn2+ and five K+ ions lie on the 3-fold axes opposite 6-rings in the large cavity, two K+ ions are off the plane of the 8-rings, two K+ ions are recessed deeply off the plane of the 8-rings, and the remaining a half Zn2+ ion lie on the 3-fold axes opposite 6-rings in the sodalite cavity. A half Zn2+ ion and an I- ion per unit cell are found in the sodalite units, indicating the formation of a ZnI2 molecule in 50% of the sodalite cavities. Each ZnI2 (Zn-I = 3.35(5) A) is held in place by the coordination of its one Zn2+ ion to the zeolite framework oxygens and by the coordination of its two I- ions to K+ ions through 6-rings (I-K = 3.33(8) A). Three additional I- ions per unit cell are found opposite a 4-ring in the large cavity and form a K3I2+ and two K2ZnI3+ ionic clusters, respectively.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.6 s.336
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• pp.59-66
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• 2005

CMOS LC VCO for tri-bind wireless LAN applications was designed in 1.8V 0.18$\mu$m CMOS process. PMOS transistors were chosen for VCO core to reduce flicker noise. The possible operation was verified for 5.8GHz band (5.725$\~$5.825GHz), 5.2GHz band (5.150$\~$5.325GHz), and 2.4GHz band (2.412$\~$2.484GHz) using the switchable L-C resonators. To linearize its frequency-voltage gain (Kvco), optimized multiple MOS varactor biasing technique was used for capacitance linearization and PLL stability improvement. VCO core consumed 2mA current and $570{\mu}m{\times}600{\mu}m$ die area. The phase noise was lower than -110dBc/Hz at 1MHz offset for tri-band frequencies.

• Korean Journal of Animal Reproduction
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• v.4 no.1
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• pp.28-34
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• 1980

This experiment was carried out to study effects fo dosage and insemination interval on fertility and hatchability of whole semen and diluted semen with yolk skim milk and skim milk dilutors. The results obtained are as follows: 1. Whole semen showed higher fertility than diluted semen with yolk skim milk and skim milk dilutors. In case of diluted semen, the fertility was higher in 0.04$m\ell$ dosage than 0.02$m\ell$ and in skim milk than yolk skim milk dilutor. 2. The average fertility in inseminational intervals of 6, 5, 4 and 3 days was 52.4, 35.5, 48.7 and 44.2% in whole semen and 40.6, 17.2, 13.9 and 20.5% in 0.04$m\ell$ diluted semen with yolk skim milk dilutor. The fertility was not improved by shortening of insemination interval. 3. There was no considerable difference in hatchability of fertilized egg among the dosage of 0.02$m\ell$ of whole semen, 0.02$m\ell$ and 0.04$m\ell$ of diluted semen with yolk skim milk, and among the insemination intervals of 6, 5, 4 and 3 days. 4. Some differences in fertility among the passed days after insemination were decreased in the whole semen by shortening insemination interval from 6 and 5 days to 4 and 3days and also decreased in the diluted semen by shortening it to 3 days and by increasing dosage from 0.02$m\ell$ to 0.04$m\ell$. 5. Hatchability of fertilized egg showed no difference among the passed days during 6 days insemination interval both in the whole semen and the diluted semen. 6. The whole semen and the diluted semen with skim milk had not considerable difference in fertility among the passed days during 3 and 4 days insemination intervals, but the diluted semen with yolk skim milk had. 7. Hatchability of fertilized egg from the whole semen diluted semen with yolk skim milk and skim milk dilutors showed no difference among the passed days during 3 and 4 days insemination intervals.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2256-2268
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• 2018

Hydrophilic and hydrophobic polyethersulfone (PES)-zinc oxide (ZnO) sublayers were prepared by loading of ZnO nanoparticles into PES matrix. Both porosity and hydrophilicity of the hydrophilic sublayer were increased upon addition of hydrophilic ZnO, while these were decreased for the hydrophobic sublayer. In addition, the results demonstrated that the hydrophilic membrane exhibited smaller structural parameter (S value or S parameter or S), which is beneficial for improving pure water permeability and decreasing mass transfer resistance. In contrast, a higher S parameter was obtained for the hydrophobic membrane. With a 2 M NaCl as DS and DI water as FS, the pure water flux of hydrophilic TFN0.5 membrane was increased from $21.02L/m^2h$ to $30.06L/m^2h$ and decreased for hydrophobic TFN0.5 membrane to $14.98L/m^2h$, while the salt flux of hydrophilic membrane increased from $10.12g/m^2h$ to $17.31g/m^2h$ and decreased for hydrophobic TFN0.5 membrane to $3.12g/m^2h$. The increment in pure water permeability can be ascribed to reduction in S parameter, which resulted in reduced internal concentration polarization (ICP). The current study provides a feasible and low cost procedure to decrease the ICP in FO processes.

• Journal of the Korea Society of Computer and Information
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• v.22 no.4
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• pp.67-74
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• 2017

The objective of this paper is to design broadband microstrip patch antenna for mobile communication service. The enhanced features were confirmed and proved by comparing the proposed antenna with the antennae that have been reported in the relevant literatures. The experimental results show that the impedance bandwidth(VSWR ${\leq}2$) of 19.6%(fo=1,920MHz) and the peak gain of 5.53dBi(at 1,900MHz) were obtained by the mobile communication service frequency band. The proposed antenna had the impedance bandwidth of about 3.1% larger than that of the reported microstrip antenna.

• Journal of Welding and Joining
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• v.21 no.4
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• pp.63-68
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• 2003

Scanning electron microscopy (SEM) has been used as a surface measurement instrument and a tool for lithography in semiconductor process due to its high density localized beam. For those purposes, however, the maximum current of SEM Is less than 100pA, which is not enough fo material processing. In this paper SEM was modified to increase the amount of current reaching a specimen from gun part where current is generated, the possibility of applying SEM to material processing, especially microjoining, was investigated. The maximum current of SEM after modifications was measured up to 10$\mu$A, which is about 10$^{5}$ times greater than before modifications. Through experiments such as eutectic solder wetting on thin 304 stainless steel foil and microjoining of 10$\mu$m thick 304 stainless steel, the intensity of electron beam of SEM proved to be great enough fur material processing as heat source. And a tight jig system was found necessary to hold materials close enough fur successful microloining.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.266_267
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• 2009

22.9kV HTS(High Temperature Superconducting) cable and SFCL(Superconducting Fault Current Limiter) will be installed to Icheon 154kV substation for real distribution power system operation in 2010. This paper proposes CLR (Current Limiting Resistance) specification of the SFCL and fault current condition fo the HTS cable for applying to Korean power system.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.1
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• pp.34-42
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• 2001

The influences of substrate temperature were studied when fabricating KLN thin film on amorphous substrate using an rf-magnetron sputtering method. Investigating the vaporization temperature of the each element, the excess ratio of target and the optimum deposition conditions were effectively selected when thin filmizing a material which have elements with large difference fo vaporization temperature. In order to compensate K and Li which have lower vaporization temperatures than Nb, KLN target of composition excess with K of 60% and Li of 30% was used. KLN thin film fabricated on Corning 1737 glass substrate had single KLN phase above 58$0^{\circ}C$ of substrate temperature and crystallized to c-axis direction. The optimum conditions were rf power of 100W, process pressure of 150mTorr, and substrate temperature of $600^{\circ}C$.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.10
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• pp.115-122
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• 1996

A 300MHz PLL including FVC (frequency to voltage converter) is designed and fabricated in 0.8$\mu$m CMOS process. In this design, a FVC and a 2nd - order passive filter are added to the conventional charge-pump PLL to improve the acquisition time. The dual-rijng VCO(voltage controlled oscillator) realized in this paper has a frequency range form 208 to 320MHz. Integrated circuits have been fully tested and analyzed in detail and it is proved that pull-in speed is enhanced with the use fo FVC. In VCO range from 230MHz to 310MHz, experimental results show that realized PLL exhibits 4 times faster pull-in speed than that of conventional PLL.