• Journal of the Korean Electrochemical Society
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• v.17 no.4
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• pp.222-228
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• 2014

Ni-rich system $Li[Ni_{1-x-y}Co_xMn_y]O_2$ of lithium secondary battery cathode material keep a high discharge capacity. However, by the Ni content increases, there is a problem that the electrochemical properties and stability of the structure are reduced. In order to solve these problems, research for positive ion doping is performed. The one of the cathode material, barium-doped $Li[Ni_{0.6-x}Ba_xCo_{0.1}Mn_{0.3}]O_2$ (x=0.01), was synthesized by the precursor, $Ni_{0.6}Co_{0.1}Mn_{0.3}(OH)_2$, from the co-precipitation method. The barium doped materials have studied the structural and electrochemical properties. The analysis of structural properties, results of X-ray diffraction analysis, and those results confirmed the change of the lattice from the binding energy in the structure by barium doping. Increased stability of the layered structure was observed by $I_{(006)}+I_{(102)}/I_{(101)}$(R-factor) ratio decrease. we expected that the electrochemical characteristics are improved. 23 mAh/g discharge capacity of barium-doped $Li[Ni_{0.6-x}Ba_xCo_{0.1}Mn_{0.3}]O_2$ (x=0.01) electrode is higher than discharge capacity of $Li[Ni_{0.6}Co_{0.1}Mn_{0.3}]O_2$ due to decrease overvoltage. And, through the structural stability was confirmed that improved the cycle characteristics. We caused a reduction in charge transfer resistance between the electrolyte and the electrode was confirmed that the C-rate characteristics are improved.

• Membrane Journal
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• v.22 no.4
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• pp.235-242
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• 2012

Ammonium perchlorate (AP) is primarily derived from the process of liquid incineration treatment when dismantling a solid rocket propellant. A series of batch dead-end nanofiltration (NF) and reverse osmosis (RO) membrane experiments were conducted to explore the retention mechanisms of AP under various hydrodynamic and solution conditions. Low levels of silicate type of siloxane had been detected through the GC/MS and FTIR analysis of liquid solutions extracted from solid ammonium perchlorate composite propellant (APCP). It is indicated that NF/RO membranes fouling in the presence of APCP was mainly attributed to the AP interactions because the concentration of silicate type of siloxane was negligible compared to that of AP. The osmotic pressure of AP was presumably resulted in the flux declines ranging from 13 to 17% in the case of the application of low-pressure (551 and 896 kPa for NF and RO) compared to those in application of high-pressure. The retention of AP by NF/RO membranes significantly varied from approximately 10 to 70% for NF and 26 to 87% for RO, depending on the operating and solution water chemistry conditions. The results suggested that retention efficiency of AP was fairly increased by reducing concentration polarization (i.e. application of low-pressure and stirring speed of 600 rpm) and increasing the pH of a solution. The result of this study was also consistent with the previous modeling of 'solute mass transfer of NF/RO membranes' and demonstrated that hydrodynamic and solution water chemistry conditions are to be a key factor in the retention of AP by NF/RO membranes.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1644-1651
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• 2014

Transgenic animals have become important tools for the production of therapeutic proteins in the domestic animal. Production efficiencies of transgenic animals by conventional methods as microinjection and retrovirus vector methods are low, and the foreign gene expression levels are also low because of their random integration in the host genome. In this study, we investigated the homologous recombination on the porcine ${\beta}$-casein gene locus using a knock-in vector for the ${\beta}$-casein gene locus. We developed the knock-in vector on the porcine ${\beta}$-casein gene locus and isolated knock-in fibroblast for nuclear transfer. The knock-in vector consisted of the neomycin resistance gene (neo) as a positive selectable marker gene, diphtheria toxin-A gene as negative selection marker, and 5' arm and 3' arm from the porcine ${\beta}$-casein gene. The secretion of enhanced green fluorescent protein (EGFP) was more easily detected in the cell culture media than it was by western blot analysis of cell extract of the HC11 mouse mammary epithelial cells transfected with EGFP knock-in vector. These results indicated that a knock-in system using ${\beta}$-casein gene induced high expression of transgene by the gene regulatory sequence of endogenous ${\beta}$-casein gene. These fibroblasts may be used to produce transgenic pigs for the production of therapeutic proteins via the mammary glands.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.1
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• pp.119-129
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• 2018

Companies' efforts to secure and sustain a competitive advantage in the market may also appear in the form of new product development. This has increased the importance of leveraging knowledge from other companies in a global competition that is accelerating with an accelerating product life cycle and the development of transportation and communications. In order to create valuable knowledge through the exchange and combination of knowledge, the absorptive capacity of the recipient of the knowledge should be considered as important, but also the knowledge protection tendency, which is characteristic of the knowledge transferor, should be considered. However, studies that considered these factors at the same time were very limited. This study examines the effect of suppliers 'absorptive capacity and buyer' s knowledge protection on new product development performance during the joint development of new products. In addition, we investigated the interaction effect between supplier's absorption capacity and buyer's knowledge protection tendency. For this purpose, data were collected for automobile industry, electronics industry and defense industry, where joint development of new products occurred frequently, and statistical verification was performed by regression analysis. The results showed that the absorptive capacity of the supplier was positively correlated with the performance of the new product development, and the buyer 's knowledge protection tendency had a negative relationship with the new product development performance. In addition, the absorptive capacity of the supplier and the buyer 's knowledge protection tendency have an interaction effect on the new product development result. These results suggest that suppliers' absorption capacity is an important factor in the joint development of new products, but suppliers with superior absorption capacity may have a negative impact on new product development performance if buyers have a negative attitude toward knowledge transfer.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.6
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• pp.456-464
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• 2007

This paper proposes a novel three-phase current-fed active clamp DC-DC converter for fuel cells. A single common active clamp branch is used to limit transient voltage across the three-phase full bridge and to realize zero-voltage switching(ZVS) in all switches. To apply for the power generation system current-fed type has been combined with the three-phase power conversion system. The proposed approach has the following advantages: an increase (by a factor of three) of input current and output voltage chopping frequencies; lower RMS current through the inverter switches with higher power transfer capability; reduction in size of reactive later components and the power conditioning system; better transformer utilization; increase of the system reliability. Therefore, the proposed three-phase current-fed active clamp DC-DC converter is appropriate for the boost type DC-DC converter for fuel cells and also applicable for the photovoltaic and battery charge system. The paper details the analysis, simulation and hardware implementation of the proposed system. Finally, experimental results with the proposed PWM strategy demonstrate the feasibility of the proposed scheme on a 500W prototype converter.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.4B
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• pp.323-332
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• 2006

In this paper, we consider a WDM based metro ring connecting broadband access networks by using FT-TR (Fixed Transmitter-Tunable Receiver) type access nodes and a new MAC protocol for fair transmission is proposed. The basic channel access scheme is CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance) and the transferred optical slot is changed to be empty slot by SS(Source-Stripping) which drops a packet from ring-rotated slot. This empty slot can be either used to send head-of-line packet in buffer or transmitted to next access node. In former cases, there is the improvement of network throughput, but latter case leads unfairness problem of transmission. Thus the proposed MAC protocol exploits the advantages form tow cases. It gives downstream access nodes chance to use empty slots and limits the unconditional usage of empty slots at upstream access nodes with probability as called p-Persistent MAC protocol. We use a numerical analysis to evaluate bandwidth efficiency and maximum node throughput and compares simulation results in terms of node throughput, fairness factor, transfer delay depending on probability. Under two different FT-TR type architectures for metro ring network the proposed MAC protocol is evaluated and compared.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1334-1341
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• 2007

This study identified hepatic differentially expressed genes (DEGs) affecting the marbling of muscle. Most dietary nutrients bypass the liver and produce plasma lipoproteins. These plasma lipoproteins transport free fatty acids to the target tissue, adipose tissue and muscle. We examined hepatic genes differentially expressed in a differential-display reverse transcription-polymerase chain reaction (ddRT-PCR) analysis comparing high- and low-marbled Hanwoo steers. Using 60 arbitrary primers, we found 13 candidate genes that were upregulated and five candidate genes that were downregulated in the livers of high-marbled Hanwoo steers compared to low-marbled individuals. A BLAST search for the 18 DEGs revealed that 14 were well characterized, while four were not annotated. We examined four DEGs: ATP synthase F0, complement component CD, insulin-like growth factor binding protein-3 (IGFBP3) and phosphatidylethanolamine binding protein (PEBP). Of these, only two genes (complement component CD and IGFBP3) were differentially expressed at p<0.05 between the livers of high- and low-marbled individuals. The mean mRNA levels of the PEBP and ATP synthase F0 genes did not differ significantly between the livers of high- and low-marbled individuals. Moreover, these DEGs showed very high inter-individual variation in expression. These informative DEGs were assigned to the bovine chromosome in a BLAST search of MS marker subsets and the bovine genome sequence. Genes related to energy metabolism (ATP synthase F0, ketohexokinase, electron-transfer flavoprotein-ubiquinone oxidoreductase and NADH hydrogenase) were assigned to BTA 1, 11, 17, and 22, respectively. Syntaxin, IGFBP3, decorin, the bax inhibitor gene and the PEBP gene were assigned to BTA 3, 4, 5, 5, and 17, respectively. In this study, the in silico physical maps provided information on the specific location of candidate genes associated with economic traits in cattle.

• Korean Security Journal
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• no.51
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• pp.223-249
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• 2017

The purpose of this study is to analyze the actual situation of crime victimization by North Korean defectors and to examine whether any of the protection and support systems for defectors has a statistically significant effect on the perceived effectiveness for preventing the criminal victimization of North Korean Defectors. The subjects of this study were 107 police officers from the 17 provincial police departments. Independent variables were (1) social adaptation education in Hanawon, (2) protection officer system, (3) legal support system, (4) private participation system, (5) support for family life, (6) community participation activity. And the dependent variable is the crime prevention effectiveness for the defectors. As a result of multiple regression analysis, it was found that the independent variables that have a significant effect on the effectiveness of prevention of crime victimization were protection officer system and support for family life. First, in order to prevent the crime victimization of North Korean defectors in advance, three kinds of protection officer system that will be received after the transfer of the residence should play the role successfully. Second, the efforts of the government and municipalities alone are insufficient for the early settlement of North Korean defectors. Therefore, it is necessary to diversify the support and protection programs for North Korean refugees through cooperation with civic organizations. Third, it is necessary to expand the legal education time so that North Korean defectors do not suffer crime because of lack of legal knowledge. Fourth, in order to prevent North Korean defectors from being victimized by various kinds of crime, it is necessary to actively support them so that family life can be stabilized.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.287-294
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• 1991

The relationships between the quantitative structure of benzotriazoles and their post-emergence growth inhibiting activity$(pI_{50})$ against Oryzae sativa L. and Echinochloa crus-galli were investigated using a generalized quantitative structure activity relationships (QSAR). According to the QSAR analysis, the free radical parameter $(E_R)$ is a very important factor and the growth inhibiting activity values showed parabolic relation to $E_R$ parameter of para-substituents(X). The activity of (3) was superior to those of (4) and (3b) is selected as the most highly effective compound. The optimal values of $E_R$ parameter of the growth inhibiting activity aganist E.crus-galli are $E_R(3)=0.52\;and\;E_R(4)=0.15$, respectively. From the result of molecular design, the substituents(X) of electron withdrawing properties and $E_R$ parameter of optimal value(0.52) were most desirable for high activity of the benzotriazoles. And in view of this, benzotriazoles may also be effective in blocking the photosynthetic electron transfer.

• KDI Journal of Economic Policy
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• v.30 no.2
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• pp.61-97
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• 2008

This paper aims at analyzing the practice of job rotation in the Korean government and putting forward policy suggestions. The Korean government is often accused of low capacity and weak competitiveness, which mainly result from the low expertise of public officials. Considering the high quality of human resources flowing into the public sector in Korea, solutions should be found from the structure of the system. This paper regards frequent position changes due to excessive job rotation as a key factor undermining the accumulation of expertise and conducts in-depth analyses. The current practice of frequent rotation shows that the average tenure period of government officials at director level and above is only about one year, far shorter than those in major developed countries, which causes many problems such as low efficiency, lack of accountability and policy consistency, and low opportunity for accumulating expertise. Simple models are set up to analyze job rotation and other alternative personnel management systems. Analyses find that it would be desirable to have each individual experience various positions during the initial rotation period to find his/her own aptitude, and then accumulate expertise by settling in at a certain specialized field for a prolonged period of time based on the revealed aptitude in mid and high positions. This turns out to be in line with the structure of the Career Development Program which is being introduced. The model-based analysis of this paper distinguishes this study from preceding ones conducted in the traditional framework of personnel management study. Practical measures to mitigate the problems of frequent job rotation include rotating within the area of specialty, narrowing the scope of transfer, and reinforcing the minimum tenure period. However, since the current frequent rotation is fundamentally attributable to the rank system based on seniority, the present civil service classification system needs to be converted into a position classification system in the long run.