• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.96-109
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• 1997

In order to simulate the corrosion behavior of Zr-4 alloy in pressurized water reactors it was implanted (or bombarded) with 190ke V $Zr^+\; and \;Ar^+$ ions at liquid nitrogen temperature and room temperature respectively up to a dose of $5times10^{15} \sim 8\times10^{16} \textrm{ions/cm}^2$ The oxidation behavior and electrochemical vehavior were studied on implanted and unimplanted samples. The oxidation kinetics of the experimental samples were measured in pure oxygen at 923K and 133.3Pa. The corrosion parameters were measured by anodic polarization methods using a princeton Applied Research Model 350 corrosion measurement system. Auger Electron Spectroscopy (AES) and X-ray Photoelectric Spectroscopy (XPS) were employed to investigate the distribution and the ion valence of oxygen and zirconium ions inside the oxide films before and after implantation. it was found tat: 1) the $Zr^+$ ion implantation (or bombardment) enhanced the oxidation of Zircaloy-4 and resulted in that the oxidation weight gain of the samples at a dose of $8times10^{16}\textrm{ions/cm}^2$ was 4 times greater than that of the unimplantation ones;2) the valence of zirconium ion in the oxide films was classified as $Zr^0,Zr^+,Zr^{2+},Zr^{3+}\; and \;Zr^{4+}$ and the higher vlence of zirconium ion increased after the bombardment ; 3) the anodic passivation current density is about 2 ~ 3 times that of the unimplanted samples; 4) the implantation damage function of the effect of ion implantation on corrosion resistance of Zr-4 alloy was established.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.529-535
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• 1996

This study was performed to investigate some quality characteristics of 새려 prepared from soybean milk and various seaweed(Undaria pinnatifida, Laminaria japonica, Porpyra tenera, Enteromorpha sp., Codium sp.) pulps in the ration of 9:1(v:v) with 20% MgCl2. The yields of tofu containing Undaria pinnatifida, Laminaria japonica, or Enteromorpha sp. increased but porphyra tenera, Codium sp. decreased in comparison with tofu prepared from whole soybean milk. The protein content of tofu containing Undaria pinnatifida, Laminaria japonica, Porphyra tenera, or Codium sp. increased but Enteromprpha sp. decreased in comparison with the tofu prepared from whole soybean milk. The content of Ca in Undaria pinnatifida, Porphyra tenera added tofu was higher than that of the tofu prepared from whole soybean milk or other seaweeds added tofu. In sensory evaluation the texture, color, taste of tofu were favored with the addition of sea mustard(Undaria pinnatifida) pulp than that of the tofu prepared from whole soybean milk or tofu prepared other seaweed. Tofu prepared was possible with adding 0.5~1.5% sea mustard to soybean milk but the feasible added amount level was 1% of sea mustard. The yields, protein Ca, and K content of tofu were increased by the more adding amount of sea mustard tan tat of the tofu prepared from whole soybean milk. The hardness values of 1% sea mustard added tofu were decreased than that of the tofu prepared from whole soybean milk ; on the other hand, elasticity, cohensiveness, gumminess and brittleness of tofu with sea mustard increased. The L and a values of tofu were lower and b values were higher with the addition of 1% sea mustard. The content of histidine, tyrosine, leusine, and phenylalanine were decreased but the other amino acid were increased in tofu prepared from 1% sea mustard pulp added to soybean milk. The saturated fatty acid and monoene fatty acid content of tofu were increased and C18:2, C18:3(${\gamma}$), C18:3, C20:5 of polyene fatty acid were slightly decreased in tofu prepared from 1% sea mustard pulp added to soybean milk.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.1
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• pp.43-52
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• 2018

This paper presents the performance of a Phase Shift Full Bridge (PSFB) converter with inductive load and a new current control scheme to improve dynamic response of output current with various inductive loads. Enhanced dynamic model is used which includes leakage inductance and inductive load. Effect of changing of inductive load was analyzed in detail. Proposed current control scheme is designed based on phase margin specifications. As a result, the proposed current control scheme helps to improve the dynamic response in comparison with the existing current control scheme. The performance of the designed controller is verified by a 500 A PSFB converter. The results will be utilized for high current applications with high inductive load such as superconducting devices.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.1
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• pp.23-29
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• 2018

A stand-alone Photovoltaic (PV) system is one of the most important energy system for Mongolian nomadic herders. Basically, a stand-alone PV system uses two DC-DC converters. This makes the system costly, size bigger and difficult to move from one place to another place for the nomadic herders. A combined control algorithm for charging the battery using Stage of Charge (SOC) and Maximum Power Point Tracking (MPPT) is proposed in this paper. The batteries are charged by the three stage method; bulk, absorption and float charge. In the bulk stage used the MPPT function in this study. The performance of the proposed control algorithm is evaluated in both steady and changing weather conditions. The results are obtained using PSIM software. The results obtained in this paper are useful in designing a stand-alone PV system in the rural life like Mongolian nomadic herders.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.1
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• pp.31-41
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• 2018

This paper discusses a structure design and thermal analysis of cryogenic conduction cooling system for a high current HTS DC reactor. Dimensions of the conduction cooling system parts including HTS magnets, bobbin structures, current leads, support bars, and thermal exchangers were calculated and drawn using a 3D CAD program. A finite element method model was built for determining the optimal design parameters and analyzing the thermo-mechanical characteristics. The operating current and inductance of the reactor magnet were 1,500 A, 400 mH, respectively. The thermal load of the HTS DC reactor was analyzed for determining the cooling capacity of the cryo-cooler. Hence, we carried out the operating test of conduction cooling system of the 1st stage area with high current flow. The cooper bars was cooled down to 40 K and HTS leads operated stably. As a experiment result, the total heat load of the 1st stage area is 190 W. The study results can be effectively utilized for the design and fabrication of a commercial HTS DC reactor.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.677-682
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• 1991

Extraction of soybean oil from full tat soybean flour was performed using a supercritical carbon dioxide extraction system. Extraction pressure and temperature of the process were 3,000-7,000 psig and $40-70^{\circ}C$, repectively. For the extraction of lg of soybean oil, 25l of carbon was consumed at 7,000 psig and $60^{\circ}C$, whereas more than 2501 of carbon dioxide was consumed at 3,000 psig and $60^{\circ}C$. The solubility of soybean oil in supercritical carbon dioxide decreased with the increase in temperature below 6,000 psig, and the reverse trend was observed above 6,000 psig. At 6,000 psig the solubilities were shown to be, constant regardless of extraction temperature. Soybean oils , extracted with supercritical carbon dioxide were lighter in color and contained less phosphorus than those extracted with hexane.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.234-241
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• 2001

The C-terminal 393 bp region of the human interleukin-16 (IL-16) gene was cloned and expressed in E. coli along with mammalian cell lines. Recombinant IL-16 expressed from E. coli was 22 kDa on SDS-PAGE and showed 260% of chemoattractant activity at a concentration of $0.1\;{\mu}g/ml$. HeLa, COS, and Neuro-2a cells were transduced by recombinant retrovirus vector pLNC/IL-16/IRES/TK and the intracellular and secreted amounts of IL-16 produced by HeLa/IL-16/TK, COS/IL-16/TK, and Neuro-2a/IL-16/TK cells were determined by enzyme-linked immunosorbent assay (ELISA). HeLa/IL-16/TK $(1{\times}10^5)$ and COS/IL-16/TK $(1{\times}10^5)$ cells secreted 36.1 and 13.3 ng of IL-16 for 48 h, respectively. Forty-nine ng and 86.4 ng of IL-16 remained in the cell lysates of HeLa/IL-16/TK and COS/IL-16/TK. Intracellular and secreted amounts of IL-16 from Neuro-2a/IL-16/TK $(5{\times}10^5)$ cells during 24 h cultivation were 50 ng and 3.3 ng, respectively. Also, HeLa and COS cells wee stably transfected with mammalian expression vector pCRIII/IL-16. Both culture media and cell lysates prepared from HeLa/IL-16 cells and COS/IL-16 cells showed chemoattractant activity ranging from 190% to 460% as compared to the control experiment. Expression of the herpes simplex virus thymidine kinase (HSV0tk) gene in pLNC/IL-16/ IRES/TK bicistronic retroviral expression vector was verified by performing a genciclovir (GCV) sensitivity assay. Finally, IL-16 repressed Tat-transactivated human immunodeficiency virus type 1 long terminal repeat (HIV-1 LTR) promoter activity.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.264-270
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• 2016

This study examined how the police officers use their annual leaves. While Korean police officers have burdens of heavy workload exceeding their regular office hours, they are passive to get leaves to keep in shape from long hours of work, to maintain the appropriate level of work productivity, and to secure time for leisure and cultural activities. It appeared that most of the police officers surveyed haven't used their annual leaves for less than half of the days designated by law. It also appeared tat female officers used more leaves than male officers, and married officers than single ones. Considering the characteristics of work environment, it showed that officers doing shift work had less days of leaves than officers in non-shift work. The reasons why the police take leaves passively lie on various factors that heavy workload, work-oriented life, work-oriented police organizational culture preceding family and so forth. Therefore, it needed to supplement the personnels to meet the needs of overwhelming workload of the police and to allocate the work properly in advance. In addition, it needed to raise the awareness of the police managers and proliferation of organizational culture to place emphasis on balance between work and family.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.51-56
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• 2013

Many intracellular proteins and signaling cascades contribute to the sensitivity of N-methyl-D-aspartate receptors (NMDARs). One such putative contributor is the serine/threonine kinase, protein kinase C (PKC). Activation of PKC by phorbol 12-myristate 13-acetate (PMA) causes activation of extracellular signal-regulated kinase (ERK) and promotes the formation of new spines in cultured hippocampal neurons. The purpose of this study was to examine which PKC isoforms are responsible for the PMA-induced augmentation of long-term potentiation (LTP) in the CA1 stratum radiatum of the hippocampus in vitro and verify that this facilitation requires NMDAR activation. We found that PMA enhanced the induction of LTP by a single episode of theta-burst stimulation in a concentration-dependent manner without affecting to magnitude of baseline field excitatory postsynaptic potentials. Facilitation of LTP by PMA (200 nM) was blocked by the nonspecific PKC inhibitor, Ro 31-8220 ($10{\mu}M$); the selective $PKC{\delta}$ inhibitor, rottlerin ($1{\mu}M$); and the $PKC{\varepsilon}$ inhibitor, TAT-${\varepsilon}V1$-2 peptide (500 nM). Moreover, the NMDAR blocker DL-APV ($50{\mu}M$) prevented enhancement of LTP by PMA. Our results suggest that PMA contributes to synaptic plasticity in the nervous system via activation of $PKC{\delta}$ and/or $PKC{\varepsilon}$, and confirm that NMDAR activity is required for this effect.

• The Transactions of the Korea Information Processing Society
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• v.5 no.10
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• pp.2663-2675
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• 1998

The billing manabement techniques for multiple services in the B-ISDN network have been rarely developed. In fact, the management techniques including billing manabement only focus on a single service environment. In this paper, we propose a billing management system architecture for the multiple services in a Broadband access network. The architecture is based in OSI system management infrastruture and TMN Q3 interface to exchange and process the billing information from access node that is an ATM Cross connecter. The system is designed to actively adopt the rapidly changing service environments and B-ISDN network management techniques. Futhermore, this system supports multiple services providers by real-time collector and charging functions for their requirements compared to the previous methodologies tat only use the statistical data.