• KSBB Journal
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• v.25 no.3
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• pp.265-270
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• 2010

Simvastatins are widely used to reduce endogenous cholesterol synthesis and improve hypercholesterolemia. Also, simvastatin have been shown to induce both angiogenic and angiostatic responses. In this study, It was attempted to resolve this controversy by studying the effects of simvastatin on the cell migration and invasion with the proteinases secretion and expression pattern. U-373-MG cells treated with low dose of simvastatin ($0.001{\sim}0.5\;{\mu}M$) showed the induction of migration and invasion compared with the addition of a control buffer. On the contrary, high dose of simvastatin ($1{\sim}20\;{\mu}M$) showed the reduction of migration and invasion compared with the addition of a control buffer. It was also showed that simvastatin-regulated migrative and invasive phenotypes were consistent with the secretion and expression pattern of matrix metalloproteinase-2 (MMP-2), MMP-9 and plasmin.

• Fire Science and Engineering
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• v.33 no.6
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• pp.114-119
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• 2019

We found metallic migration phenomena at the fire scene in Printed circuit board (PCB) of LED light equipment which are commonly used. Accordingly we did this study. In order to generate rapidly metallic migration, we experiment the water drop test under low voltage (3.0 V) and a small amount of water condition. As a results of our experiment, we saw the growth of metallic migration of Copper and checked directly short of the PCB between isolated two poles by Cu migration. Finally we saw the shape of dendrite pattern by Cu migration using Scanning electron microscope (SEM) and analyzed that components via Energy dispersive Spectrometer (EDS).

• The Plant Pathology Journal
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• v.32 no.4
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• pp.340-346
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• 2016

To understand how Bursaphelenchus xylophilus kills pine trees, the differences between the effects of B. xylophilus and B. mucronatus on pine trees are usually compared. In this study, the migration and attacking ability of a non-pathogenic B. mucronatus in Pinus thunbergii were investigated. The distribution of B. mucronatus and the number of dead epithelial cells resulting from inoculation were compared with those of the pathogenic B. xylophilus. Although B. mucronatus is non-pathogenic in pines, its distribution pattern in P. thunbergii was the same as that of B. xylophilus. We therefore concluded that the non-pathogenicity of B. mucronatus could not be attributed to its migration ability. The sparse and sporadic attacking pattern of B. mucronatus was also the same as that of B. xylophilus. However, the number and area of the dead epithelial cells in pine cuttings inoculated with B. mucronatus were smaller than in those cuttings inoculated with B. xylophilus, meaning that the attacking ability of B. mucronatus is weaker than that of B. xylophilus. Therefore, we concluded that the weaker attacking ability of B. mucronatus might be the factor responsible for the non-pathogenicity.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.561-579
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• 2008

The population concentration in Seoul has caused the chronic housing shortage. Accordingly the new towns in the Capital region were developed to alleviate overcrowding conditions in Seoul. The purpose of this study is to analyze changes of migration and commuting patterns according to new town development in the Capital region for the period of $1995{\sim}2005$. Further this study examines the changes of self-sufficiency level for new towns using jobs to housing ratio. During the last 10 years, the migration pattern in the Capital region has been pretty much followed the new town development. Such a migration pattern has influenced the commuting patterns, expanding the Seoul Metropolitan Area into northeastern par of the Capital region. The result reveals that self-sufficiency levels of new towns have become higher over the period of $1995{\sim}2005$, indicating that new towns are gradually strengthening their economic functions and have potential to become new business centers in the future. Therefore, the policy focusing on the increase of the job-housing balance ratio and self-sufficient level in new towns will be a desirable policy alternative to solve the transportation problems in the Capital region.

• Journal of Embryo Transfer
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• v.14 no.1
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• pp.47-57
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• 1999

Among proteins separated from methanol extract of follicular fluid with superose column, the components inducing sperm swim-up separation through sucrose layer were analysed with superose column in Smart system and SDS-PAGE. And the results obtained were as follows; The fractions of retention volume (RV) 0.83ml and RV 1.36ml separated with superose column should stimulate sperm migration and movement. However, RV 0.83 fraction was consisted of complex materials containing RV 1.36 component. RV 1.36 fraction contained a BSA analogue of 67 kilodaltons (Kd) and showed identical peak pattern with BSA fraction V. In conclusion, the protein of 67 Kd in follicular fluid should stimulate sperm migration and movement.

• The Transactions of the Korea Information Processing Society
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• v.7 no.5
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• pp.1511-1519
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• 2000

Inthis paper, we present an efficient migration strategy of mobile agent for data mining application. The purpose of the proposed algorithm is to set up the best migration plan of mobile agent with regard to minimizing network execution time .In order to verify the effectiveness of the proposed algorithm, we designed a performance evaulation model for three paradigms from data mining, i.e. RPC, mobile agent and mobile agent with locker pattern, and we then evaluated the algorithm by simulation.

• Nuclear Engineering and Technology
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• v.30 no.3
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• pp.245-261
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• 1998

In order to validate the variable aperture channel model that can deal with the non-uniform How rate in flow domain, migration experiments of conservative tracer were performed in two artificial fractures, a parallel and a wedge-shaped fracture. These different fracture shapes were designed to give different flow pattern. The fractures were made from a transparent acrylic plastic plate and a granite slab with dimensions of 10 $\times$ 61 $\times$ 61 cm. Uranine (Fluorescein sodium salt) was used as a conservative tracer. The volumetric flow rates of uranine feed solution were 30 mL/ hr, giving a mean residence time in the fracture of approximately 24 hours for the parallel fracture and 34 hours for the wedge-shaped fracture. The migration plumes of uranine were photographed to obtain profiles in space and time for movement of a tracer in fractures. The photographed migration plume was greatly affected by the geometric shape of fractures. The variable aperture channel model could have predicted the experimental results for the parallel fracture with a large accuracy. It is expected that the variable aperture channel model would be effective to predict the transport of the contaminant, especially, with the flow rate variation in a fracture.

• Journal of the Korean Geographical Society
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• v.42 no.6
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• pp.930-939
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• 2007

This study intends to demonstrate that the population decrease in the City of Busan has been resulted from the move of the city's population towards suburbs as well as the out-migration towards the Seoul metropolitan area. To grasp the pattern in the spatial shift of the Busan's population, I analyze the change of population and households within the city and the migration at the inter-regional and intra-metropolitan scales. The major findings of the study are as follows: First, Busan has experienced population decline since 1995, as other large cities, such as Seoul and Daegu have done. Second, despite the population decrease, the number of households has been increased in Busan. Third, the residents of Busan have mostly moved not only to the Seoul metropolitan area but also to the suburban region of Busan. This finding may well contradict the long-standing belief that the continued decrease in the Busan population could be the result of the out-migration toward the Seoul metropolitan area. Fourth, the residential suburbanization in Busan can be interpreted as the extensive intra-metropolitan dispersion, which means the growth of the Busan metropolitan area.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.15 no.2
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• pp.137-142
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• 2011

In this paper we formulate a predator-prey system in two patches in which the per capita migration rate of each species is influenced only by its own density, i.e. there is no response to the density of the other one. Numerical studies show that at a critical value of the bifurcation parameter the system undergoes a Turing bifurcation, i. e. the stable constant steady state loses its stability and spatially non-constant stationary solutions, a pattern emerge.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.109-120
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• 2013

As information-oriented industry has been developed and electronic devices has come to be smaller, lighter, multifunctional, and high speed, the components used to the devices need to be much high density and should have find pattern due to high integration. Also, diverse reliability problems happen as user environment is getting harsher. For this reasons, establishing and securing products and components reliability comes to key factor in company's competitiveness. It makes accelerated test important to check product reliability in fast way. Out of fine pattern failure modes, failure of Electrochemical Migration(ECM) is kind of degradation of insulation resistance by electro-chemical reaction, which it comes to be accelerated by biased voltage in high temperature and high humidity environment. In this thesis, the accelerated life test for failure caused by ECM on fine pattern substrate, $20/20{\mu}m$ pattern width/space applied by Semi Additive Process, was performed, and through this test, the investigation of failure mechanism and the life-time prediction evaluation under actual user environment was implemented. The result of accelerated test has been compared and estimated with life distribution and life stress relatively by using Minitab software and its acceleration rate was also tested. Through estimated weibull distribution, B10 life has been estimated under 95% confidence level of failure data happened in each test conditions. And the life in actual usage environment has been predicted by using generalized Eyring model considering temperature and humidity by developing Arrhenius reaction rate theory, and acceleration factors by test conditions have been calculated.