• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.7
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• pp.46-52
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• 2006

The effects of surface treatment on the hydrogen storage properties of a $Mg_2Ni$ alloy particle were investigated by the microvoltammetric technique, in which a carbon-filament microelectrode was manipulated to make electrical contact with the particle in a KOH aqueous solution. It was found that the hydrogen storage properties of $Mg_2Ni$ at room temperature were improved by the surface treatment with a nickel plating solution. The sodium salts(sodium phosphate and sodium dihydrogen citrate) contained in the nickel plating solution made the alloy form an amorphous-like state, resulting in an improved hydrogen charge/discharge capacity at room temperature as high as about 150[mAh/g] from the original value of 17[mAh/g]. Potential-step experiment was carried out to determine the apparent chemical diffusion coefficient of hydrogen atom($D_{app}$) in the alloy. Since the alloy particle we used here was a dense, conductive sphere, the spherical diffusion model was employed for data analysis. $D_{app}$ was found to vary the order between $10^{-8}{\sim}10^{-9}[cm^2/s]$ over the course of hydrogenation and dehydrogenation process.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.175-178
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• 1993

Alkaline .alpha.-amylase expressed in the transformant, Baciollus subtills MB809, containing alkaline amylase gene cloned from alkalophilic Bacillus sp. AL-8, was purified through for step separation processes. The purified alkaline .alpha.-amylase had molecular weight of app[roximately 59, 000 daltons on SDS-PAGE and Sephaex G-100 gel filtration. Amino acid sequence of terminal portion of the enzyme was analyzed with pure amylase eluted form the SDS-PAGE gel. N-terminal amino acid sequence of .alpha.-amylase was determined by the Edman degradation method and resulted in $NH_{2}$-ser-thr-ala-pro-ser-(ile)-lys-ala-gly-thr-(ile)-leu. For C-terminal amino acid sequencing, purified .alpha.-amylase was digested with carboxypuptidase A and B, and reverse-phase HPLC gradient elution system resulted in -thr-trp-pro-lys-COOH.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1199-1209
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• 2017

Food environment has been going through significant changes with the introduction of Information and Communication Technology (ICT). This study was conducted to investigate the current development status of ICT related to food delivery service by analyzing the relevant registered patents according to consumer buying process. Patents registered between 2002 and 2016 were searched with 'food' and 'delivery' as main keywords through Korea Intellectual Property Rights Information Service (www.kipris.or.kr). The search resulted in 624 patents among which 219 patents were related to food delivery service; 108 patents based on ICT were selected and analyzed. The patents were examined by applicant and year. The patents were classified into the six steps of consumer buying process: 'need recognition', 'information search', 'evaluation', 'choice', 'purchase', and 'postpurchase evaluation'. Patents belonging to more than one step were coded to all the corresponding steps. The patents were registered mainly by domestic companies (50.9%) and individuals (35.2%), having shown dramatic increase of registration since 2012. Over 2/3 (67.6%) of the patents were related to the 'purchase' step. About 32% were associated with the 'information search' step. Approximately 18% of the patents were relevant to the 'evaluation' and 'choice' steps, respectively. The numbers of patents related to the 'postpurchase evaluation (13.9%)' and 'need recognition (12.0%)' steps were relatively low. The current ICTs related to food delivery service in Korea were largely associated with service providers' profit generation rather than consumers' benefit. There is still much room for technology development that could contribute to increasing consumers' benefit.

• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.374-378
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• 1991

The electrochemical reduction behavior of Bilirubin (BR) in phosphate buffer (pH 7.8) solution was studied by DC polarography, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. In DC polarogram, two reduction waves of BR were found. The half wave potentials of two reduction waves were -1.32 and -1.51 volts vs. Ag/AaCl respectively. The current type of 1st reduction wave was diffusion-controlled and the 2$^{nd}$ reduction wave was diffusion current containing a little kinetic current. The electrochemical reduction process of BR at each reduction step was all irreversible. The prewave appeared at lower concentration than 3.4 ${\times}$ 10$^{-4}$M, this prewave was identified as adsorption prewave. And the number of electron transfered in reduction steps, n$_{app}$ was two for the 1st reduction step and one for the 2$^{nd}$ reduction step.

• Journal of the Korean Electrochemical Society
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• v.9 no.2
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• pp.95-99
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• 2006

Electrochemical properties were studied for a single particle of active material of hydrogen storage alloy $(MmNi_{3.55}Co_{0.75}Mn_{0.4}Al_{0.3})$ and nickel hydroxides $(NiOH)_2$ for the secondary Nickel Metal Hydride (Ni-MH) batteries using the microelectrode, which was manipulated to make electrical contact with an active material particle for cyclic voltammograms (CV) and potential-step experiments. As a result of CV test, it was found that three kinds of hydrogen oxidation peaks at -0.9, -0.75 and -0.65 V and hydrogen evolution peak at -0.98 V for hydrogen storage alloy were separately observed and two kinds of peaks of proton oxidation/reduction at 0.45 and 0.32 V and oxygen evolution reaction (OER) at 0.6 V for nickel hydroxides were also more clearly observed. Furthermore hydrogen diffusion coefficient within a single particle was also found to vary the order between $10^{-9}\;and\;10^{-10}cm^2/s$ over the course of hydrogenation and dehydrogenation process for potential-step experiments.

• Journal of Microbiology and Biotechnology
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• v.24 no.12
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• pp.1673-1678
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• 2014

The interactive inhibitory effects of pH and chloride on the catalysis of laccase from Trametes versicolor were investigated by studying the alteration of inhibition characteristics of sodium chloride at different pHs for the oxidation of 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid). At pH 3.0, the addition of sodium chloride (50 mM) brought about a 40-fold increase in $K{_m}^{app}$ and a 4-fold decrease in $V_{max}{^{app}}$. As the pH increased to 7.0, the inhibitory effects of sodium chloride became significantly weakened. The mixed-inhibition mechanism was successfully used to quantitatively estimate the competitive and uncompetitive inhibition strengths by chloride at two different pHs (pH 3.0 and 6.0). At pH 3.0, the competitive inhibition constant, $K_i$, was 0.35 mM, whereas the uncompetitive inhibition constant, $K{_i}^{\prime}$, was 18.1 mM, indicating that the major cause of the laccase inhibition by chloride is due to the competitive inhibition step. At a higher pH of 6.0, where the inhibition of the laccase by hydroxide ions takes effect, the inhibition of the laccase by chloride diminished to a great extent, showing increased values of both the competitive inhibition constant ($K_i=23.7mM$) and uncompetitive inhibition constant ($K{_i}^{\prime}=324mM$). These kinetic results evidenced that the hydroxide anion and chloride share a common mechanism to inhibit the laccase activity.

• International journal of advanced smart convergence
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• v.6 no.1
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• pp.32-38
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• 2017

In Korea, the act for promoting use of the public data has been enforced since 2013. The Key Government 3.0 Strategy was established for providing the public data as an obligation of public authorities for users to use them free of charge. The aim of open public data and using them targeted by the government is creation of a solution for vitalizing the economy by using the public data. However, the reason for low usability and tangible outcomes despite unlimited provision of open government data is as follows. That is, it is essential to address the issue of difficult software technology required to access public data for using the data. However, with the open API method currently provided, the development procedure is not easy even for IT students or specialized software developers. Therefore, strategies for each step ideal for the level of developers are required to vitalize applications based on the public data and developed by ordinary users. Two strategic methods can be used for facilitating the use of public data and applications developed by ordinary users suggested in this paper on the basis of the public data portal organized by the Ministry of the Interior and provided to all ordinary users. That is, they are applications developed in the web browser environment and those developed in the PC environment. They allow ordinary users to develop and distribute applications based on the public data to contribute to enforcing the policy for facilitating the use of public data of the government just with basic training and basic knowledge from the training without using program coding knowledge of open API which requires the knowledge of development professionals.

• Journal of Korea Port Economic Association
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• v.29 no.3
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• pp.73-94
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• 2013

The necessity of shipping market information services has been on the rise which emphasizes the relevance of transaction information and market information to parties both in and outside the shipping industry. However, previous related researches have been restricted to explorations limited by the offerings of existing shipping market information providers. Users today require effective information, an efficient contents management system, interfacing to help the information provider, graphing and spread sheets to facilitate and present the analyzed information through diverse formats, and reliable web and mobile services to provide information effectively with limited human resources. As a first step, service information has to be defined, so that it takes into account user utility, information retrieval and data development. Second, benchmark information and services must be provided from leading shipbrokers and research institutes. Third, a review of the latest technical trends is required to identify the most suitable technologies for servicing shipping market information. Finally, analysis is required on the implementation of a system with selected technologies, as well as the development of channels to post information which have been analyzed by users. Such a process would enable the continual redefinition of the shipping market information users actively need. The application of an X-Internet based WCMS, with a single-window dashboard providing user-customized information, and used to obtain and manage processes, add spread sheets to sustain calculations using the latest information, graph results, and to input additional information following predefined rules. Access to data and use of the system would require agreement that the system will incorporate user data and user-analyzed information into the market report, web portal, and hybrid app to provide current shipping market information appropriately and accurately to service users.

• Archives of Plastic Surgery
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• v.44 no.3
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• pp.223-227
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• 2017

Background Carpal tunnel release is one of the most common surgical procedures performed by hand surgeons. The authors created a surgical simulation of open carpal tunnel release utilizing a mobile and rehearsal platform app. This study was performed in order to validate the simulator as an effective training platform for carpal tunnel release. Methods The simulator was evaluated using a number of metrics: construct validity (the ability to identify variability in skill levels), face validity (the perceived ability of the simulator to teach the intended material), content validity (that the simulator was an accurate representation of the intended operation), and acceptability validity (willingness of the desired user group to adopt this method of training). Novices and experts were recruited. Each group was tested, and all participants were assigned an objective score, which served as construct validation. A Likert-scale questionnaire was administered to gauge face, content, and acceptability validity. Results Twenty novices and 10 experts were recruited for this study. The objective performance scores from the expert group were significantly higher than those of the novice group, with surgeons scoring a median of 74% and medical students scoring a median of 45%. The questionnaire responses indicated face, content, and acceptability validation. Conclusions This mobile-based surgical simulation platform provides step-by-step instruction for a variety of surgical procedures. The findings of this study help to demonstrate its utility as a learning tool, as we confirmed construct, face, content, and acceptability validity for carpal tunnel release. This easy-to-use educational tool may help bring surgical education to a new- and highly mobile-level.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.31-45
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• 2011

The amyloid ${\beta}$-peptide ($A{\beta}$), which originates from the proteolytic cleavage of amyloid precursor protein (APP), plays a central role in the pathogenesis of Alzheimer's disease (AD). Mounting evidence indicates that different species of $A{\beta}$, such as $A{\beta}$ oligomers and fibrils, may contribute to AD pathogenesis via distinct mechanisms at different stages of the disease. Importantly, elevation and accumulation of soluble $A{\beta}$ oligomers closely correlate with cognitive decline and/or disease progression in animal models of AD. In agreement with these studies, oligomers of $A{\beta}$ have been shown to directly affect synaptic plasticity, a neuronal process that is known to be essential for memory formation. Our previous studies showed that $A{\beta}$ induces the breakdown of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a phospholipid that regulates key aspects of neuronal function. PI(4,5)P2 breakdown was found to be a key step toward synaptic and memory dysfunction in a mouse model of AD. To this end, we seek to identify small molecules that could elevate the levels of PI(4,5)P2 and subsequently block $A{\beta}$ oligomer-induced breakdown of PI(4,5)P2 and synaptic dysfunction.. We found that (20S)Rg3, an active triterpene glycoside from heat-processed ginseng, serves as an agonist for phosphatidylinositol 4-kinase IIalpha (PI4KIIalpha), which is a lipid kinase that mediates a rate-limiting step in PI(4,5)P2 synthesis. Consequently, (20S)Rg3 stimulates PI(4,5)P2 synthesis by directly stimulating the activity of PI4KIIalpha. Interestingly, treatment of a mouse model of AD with (20S)Rg3 leads to reversal of memory deficits. Our data suggest that the PI(4,5)P2-promoting effects of (20S)Rg3 may help mitigate the cognitive symptoms associated with AD.