• Journal of the Korean Electrochemical Society
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• v.14 no.4
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• pp.231-238
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• 2011

In this work, the numerical analysis for the zincate behavior at a zinc electrode with an electrolyte flow was carried out for a ZAFC. The Nernst-Planck equation with a boundary condition of Butler-Volmer type was adopted to describe electrochemical effects of mass transfer, migration, kinetics of electrode. The Navier-Stokes equation, coupling to the Nernst-Planck equation, is also applied to describe the internal electrolyte flow fields. The validity of the numerical model is proved through the comparative analysis between numerical and experimental results. The concentration of zincate and the current density were also investigated at a zinc anode according to various electrolyte velocities. We have found the concentration of zincate decreased and the current density increased with an increase in the electrolyte velocity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.130-138
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• 1981

Discoloration of canned boiled oysters during storage is one of the serious problems which affect the quality of the products as well as the nutritive value. Usually the factors influencing the quality of canned boiled oysters are the process of pretreatments and the storage temperature of the products. In the present work, the changes of the total chlorophylls and carotenoids in the meat and the viscera of oysters were determined in order to make certain the procedure of the discoloration. In addition, the amino-N and the available lysine as factors of the nutritive value were also checked. In case of treatment with additives, direct addition of syrups containing additives just before seaming or soaking boiled oysters into the solution of additives seemed to have mild effects on retardation of discoloration. The migration of carotenoids from the viscera into the meat was faster than that of chlorophyll resulting in yellowing of the Products preceded greening caused by the chlorophylls. Treatment with $0.5\%\; Na_{2}EDTA\;of\;2.5\%$ brine retarded discoloration and available lysine loss of the Products while sodium-polyphosphate accelerated them. It was probably due to that sodium-polyphosphate could affect the softening or breakdown of the muscle of oysters. But most of all, storage temperature of canned boiled oysters seemed to be the major factor influencing the discoloration and nutritive loss of the products.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.146-156
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• 2018

Spermidine is a naturally occurring polyamine compound that has recently emerged with anti-aging properties and suppresses inflammation and oxidation. However, its mechanisms of action on anti-inflammatory and antioxidant effects have not been fully elucidated. In this study, the potential of spermidine for reducing pro-inflammatory and oxidative effects in lipopolysaccharide (LPS)-stimulated macrophages and zebrafish was explored. Our data indicate that spermidine significantly inhibited the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$), and cytokines including tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$ in RAW 264.7 macrophages without any significant cytotoxicity. The protective effects of spermidine accompanied by a marked suppression in their regulatory gene expression at the transcription levels. Spermidine also attenuated the nuclear translocation of $NF-{\kappa}B$ p65 subunit and reduced LPS-induced intracellular accumulation of reactive oxygen species (ROS) in RAW 264.7 macrophages. Moreover, spermidine prevented the LPS-induced NO production and ROS accumulation in zebrafish larvae and was found to be associated with a diminished recruitment of neutrophils and macrophages. Although more work is needed to fully understand the critical role of spermidine on the inhibition of inflammation-associated migration of immune cells, our findings clearly demonstrate that spermidine may be a potential therapeutic intervention for the treatment of inflammatory and oxidative disorders.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.101-109
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• 2005

In order to produce only a pH-controlled solution without discharging any unused solution, this work has developed a continuous electrolytic system with a pH-adjustment reservoir being placed before an ion exchange membrane-equipped electrolyzer, where as a target solution was fed into the pH-adjustment reservoir, some portion of the solution in the pH-adjustment reservoir was circulated through the cathodic or anodic chamber of the electrolyzer depending on the type of the ion exchange membrane used, and some other portion of the solution in the pH-adjustment reservoir was discharged from the electrolytic system through other counter chamber with its pH being controlled as acid or base. The phenomena of the pH being controlled in the system could be explained by the electro-migration of the ion species in the solution through the ion exchange membrane under a cell potential difference between anode and cathode and its consequently-occurring non-charge equilibriums and electrolytic water- split reactions in the anodic and cathodic chambers.

• Korea journal of population studies
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• v.21 no.1
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• pp.105-128
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• 1998

There are about 5,300,000 overseas Koreans in the world. This is about 11.8 percent of the total population of the Korean peninsular. They reside in more than one hundred nations. This exodus occurred due to forced emigration, escape from oppressive regimes, and economic opportunity. Most of them are living in the four regions, that is, China, Japan, America, and Central Asia. The purpose of this paper is to examine the pattern of Korean migration to overseas and to compare the life style of overseas Koreans. The data are taken from a sample survey, which was conducted in China, Japan, America, and Central Asia. A total of 300 respondents were interviewed in each country. The result shows that there are some differences in the lives of overseas Koreans. For example, the Koreans in Central Asia may have suffered the greatest hardship, the similar case was found in the Koreans in China. By contrast, the issue of ethnic conflict becomes the most serious problem in the Koreans in Japan. This study also shows many aspects of common Korean heritage, that is, hard work, diligence, and high level of education. In addition, the study indicates that overseas Koreans are trying to retain Korean traditional values and relationships in their families.

• The Korean Journal of Pharmacology
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• v.29 no.1
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• pp.121-130
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• 1993

This study was done to classify the proteins involved in the specific phosphorylation using the rat peripheral blood lymphocytes (rPBL) stimulated with mitogens, phorbol 12-myristate 13-acetate (PMA) and concanavalin A (Con A). The lymphocytes were incubated with $^{32}P-orthophosphate$ before PMA or Con A stimulation. The migration patterns of the phosphorylated proteins of mitogen-treated rPBL in two dimensional electrophoretic fields were analyzed after autoradiography. The stimulation of the lymphocytes with PMA and Con A increased the phosphorylation of thirteen protein fractions. The phosphorylation intensities of the protein spots differ to the treatments of the cells with specific kinase inhibitors, H-7 and W-7. These protein fractions were grouped into 3 classes, namely, PKC-mediated, CaM kinase-mediated, and other kinase mediated proteins. The effect of the duration of the stimulation on the phosphorylated behaviors occurred concurrently, not sequentially, although each individual protein fraction had a different time for the peak phosphorylation during the stimulation period upto 30 minutes. The phosphoproteins found in the cytosolic soluble fraction were phosphorylated prior to those in the pellet, whose phosphorylations were sustained at a high level for over 10 minutes. The above results suggest that the early events in lymphocyte activation involve 3 different sets of proteins which are phosphorylated by CaM kinase, PKC and other kinases, and those kinases do not work sequentially, but rather, independently or cooperatively.

• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.267-275
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• 2001

This study was conducted to investigate the characteristics of bird community and to suggest a proper way how to manage and protect bird community in Mt. Paldal, Suwon City. The survey was carried out by line transect method from March 1992 to February 1993, and from October 1998 to August 1999. Twenty-seven birds were recorded, and these birds were also classified into 14 species for residents, 8 species fur summer visitors, 4 species for winter visitors and 1 species fur passage migrant in 1992. Twenty-one birds were recorded, and these birds were also belonged to 16 species fur residents, 2 species fur summer visitors, 2 species for winter visitors and 1 species for passage migrant in 1999. In 1992, seasonal change of number of species and individuals showed a typical pattern of temperate deciduous forests, however, seasonal pattern in 1999 was somewhat differed from that of temperate deciduous forest. According to data of migration habits of bird community in same months, percentage of residents were higher in 1999 and that of summer visitors were higher in 1992. In guild analysis of breeding bird community, bush-nesting and foraging guild that utilize the bush layer as nest and food resources showed the decreasing number of species and individuals, also summer visitors did the same decreasing trends from 1983. Therefore, it should be suggest that protection of bush layer for inhabitation of bush-nesting and foraging guild and summer visitors, and it will be considered that construction of green net-work among urban forests such as Mt. Kwanggyo, Mt. Chilbo, Mt. Paldal, Mt. Sukgi and Mt Yeogi in Suwon City.

• Journal of the Korean Geographical Society
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• v.41 no.1 s.112
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• pp.73-93
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• 2006

Despite of ecological and landscape importances and public popularity of Pinaceae, not much scientific informations are known about Korean Pinaceae. Present work aims to understand the biogeography of Korean native Pinaceae, i.e., taxonomy, phylogeny, origin, life form, distribution, dispersal and migration. Korean native Pinaceae consists of five genera and sixteen species. Pinus is systematically closely related to Picea and Larix, but Abies is related to Tsuga. Boreal conifers which have migrated from NE Asia during the Pleistocene glacial epochs successfully survived, but now confined to the alpine and subalpine belts of the Korean Peninsula mainly due to climate warming since the Holocene. Species, such as Picea pungsanensis and Abies koreana have gradually adapted to local environment, and later became an endemic species of Korea. Disjunctive distribution of Pinus parviflora and Tsuga sieboldii are also indicatives of climate change of the Pleistocene. Major dispersal agent of pine trees with winged seed is wind, but wingless pine tree seeds seem to dispersed by birds and rodents. Pine trees with bigger wings are easily dispersed by wind, and now show broader distribution. Species of Pinaceae with disjunctive distribution on the alpine and subalpine belts of both North and South Korea seems to be more vulnerable to global warming.

• The Journal of Bigdata
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• v.6 no.1
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• pp.145-151
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• 2021

In recent years, digital data has been generated in all areas of human activity, and there are many attempts to safely store and process the data to develop useful services. A data lake refers to a data repository that is independent of the source of the data and the analytical framework that leverages the data. In this paper, we designed a tool to safely store various big data generated by smart cities in a data lake and ETL it so that it can be used in services, and a web-based tool necessary to use it effectively. Implement. A series of processes (ETLs) that quality-check and refine source data, store it safely in a data lake, and manage it according to data life cycle policies are often significant for costly infrastructure and development and maintenance. It is a labor-intensive technology. The mounting technology makes it possible to set and execute ETL work monitoring and data life cycle management visually and efficiently without specialized knowledge in the IT field. Separately, a data quality checklist guide is needed to store and use reliable data in the data lake. In addition, it is necessary to set and reserve data migration and deletion cycles using the data life cycle management tool to reduce data management costs.

• Nuclear Engineering and Technology
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• v.25 no.4
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• pp.529-538
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• 1993

A stochastic way using continuous time Markov process is presented to model the one-dimensional nuclide transport in fractured rock matrix as an extended study for previous work ［1］. A nuclide migration model by the continuous time Markov process for single planar fractured rock matrix, which is considered as a transient system where a process by which the nuclide is diffused into the rock matrix from the fracture may be no more time homogeneous, is compared with a conventional deterministic analytical solution. The primary desired quantities from a stochastic model are the expected values and variance of the state variables as a function of time. The time-dependent probability distributions of nuclides are presented for each discretized compartment of the medium given intensities of transition. Since this model is discrete in medium space, parameters which affect nuclide transport could be easily incorporated for such heterogeneous media as the fractured rock matrix and the layered porous media. Even though the model developed in this study was shown to be sensitive to the number of discretized compartment showing numerical dispersion as the number of compartments are decreased, with small compensating of dispersion coefficient, the model agrees well to analytical solution.