• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.2
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• pp.29-37
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• 2004

An areal elderly migration model (AEMM) was developed to assess the demand of rural development projects targeted towards elderly people. The AEMM was developed with adaptation of the gravity model to represent spatial interaction regarding amenities. Areal characteristics were classified for estimating the amenities from the perspective of net migration. From 1990 to 2000, data were acquired from USCB, PASDA, PAHEALTH, PADCNR, PFBC, and NCDC in 67 Pennsylvania counties for analysis and application. The results revealed that elderly migration can be explained not only by areal characteristics but also by spatial interaction considering the population, distances, and amenities of surrounding areas.

• IMMUNE NETWORK
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• v.5 no.4
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• pp.247-251
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• 2005

Background: Natural killer (NK) cells are CD3 (-) CD14 (-) CD56 (+) lymphocytes. They play an important role in the body's innate immune response. They can induce spontaneous killing of cancer cells or virus-infected cells via the Fas/Fas ligand or the granzyme/perforin systems. The corticotropin-releasing hormone (CRH) is an important regulator for the body's stress response. It promotes proliferation and migration of various cancer cells through the CRH type 1 receptor under stress, and also inhibits NK or T cell activity. However, the relationship of CRH and NK cell migration to the target has not been confirmed. Herein, we study the effect of CRH on NK cell migration. Methods: We used the human NK cell line, NK-92MI, and tested the expression of CRH receptor type 1 on NK-92MI by RT-PCR. This was to examine the effect of CRH on tumor and NK cell migration, thus NK cells (NK-92MI) were incubated with or without CRH and then each CRH treated cell's migration ability compared to that of the CRH untreated group. Results: We confirmed that CRH receptor type 1 is expressed in NK-92MI. CRH can decrease NK cell migration in a time-/dose-dependent manner. Conclusion: These data suggest CRH can inhibit NK cell migration to target cells.

• The Korean Journal of Community Living Science
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• v.20 no.2
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• pp.193-204
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• 2009

Although the majority of elderly are residentially stable, many western studies have recently reported that there has been a gradual growth of retirement migration. However, little is known about that in Korea. Therefore, this study intended to examine the trend and nature of elderly migration. For this purpose, inter- and intra-province migration among the aged 65 and over were analyzed, using the migration data of the Korea National Statistical Office, compiled from the 2000 and 2006 resident registration records. The results were as follows. First, there was an increase of elderly migrants to 531 thousand persons in 2006 from 383 thousand persons in 2000. Secondly, the migration rate of elderly has steadily grown with a 11.7% in 2000 and 12% in 2006. Also, the move of female among old population was active but this trend tended to decrease in 2006. Thirdly, the number of provinces which showed a positive net inter-province migration of old population increased from 7 provinces in 2000 to 8 provinces in 2006. Fourthly, we found that the destinations of elderly migrants were mostly neighboring province except the Chungnam, Jeonbuk, and Jeju. These results suggested that elderly migration would be expected to increase gradually and be important in the future of Korea.

• Genomics & Informatics
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• v.17 no.4
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• pp.37.1-37.8
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• 2019

Isolation-with-migration (IM) models have become popular for explaining population divergence in the presence of migrations. Bayesian methods are commonly used to estimate IM models, but they are limited to small data analysis or simple model inference. Recently three methods, IMa3, MIST, and AIM, resolved these limitations. Here, we describe the major problems addressed by these three software and compare differences among their inference methods, despite their use of the same standard likelihood function.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.5
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• pp.39-53
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• 2017

The purpose of this study was to investigate the effects of the rural migration factors, degree of preparation for migration, lifestyle conditions and support policies reflected against the family satisfaction of the migration. In this study family factors were used as control variables. Independent variables for this study will consist of the factors of rural migration, the degree of preparation for migration, living conditions of the farmers and the support policies, where as the dependent variable is the satisfaction of migration with an adjusting factor of the family satisfaction which will be further analysed to identify its effects on the dependent variable. For this study, a questionnaire survey was conducted for the residents and 237 valid questionnaires were collected. Multiple regression analysis was performed based on the collected data where demographic attributes being the controlling variable, and regression analysis was performed for the adjusting variable of the family. As the economic factor increases, the level of satisfaction generated to be higher in rural migration. As for the degree of preparation, living condition and support policies resulted, great quantity of green nature, safety and agriculture startup support, respectively, indicated a positive effect to the satisfaction level of migration. From the results, adjustment effect of the family factors on the economic, nature, convenience and satisfaction of the migration have appeared. The conclusion of this study is that policy support, regional stability, and economic gain are the most important factors to increase satisfaction and to reduce re-migration rate to city.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.3
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• pp.1002-1015
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• 2018

The advent of Internet of Things (IoT) and the evident inadequacy of Cloud networks concerning management of numerous end nodes have brought about a shift of paradigm giving birth to Fog computing. Fog computing is an extension of Cloud computing that extends Cloud resources at the edge of the network, closer to the user. Cloud computing has become one of the essential needs of people over the Internet but with the emerging concept of IoT, traditional Clouds seem inadequate. IoT entails extremely low latency and for that, the Cloud servers that are distant and unknown to the user appear to be unsuitable. With the help of Fog computing, the Fog devices installed would be closer to the user that will provide an immediate storage for the frequently needed data. This paper discusses data migration between different storage types especially between Cloud devices and then presents a mechanism to migrate data between Cloud and Fog Layer. We call this mechanism Adaptive Deadline-Aware Scheme (ADAS) for Data migration between Cloud and Fog. We will demonstrate that we can access and process latency sensitive "hot" data through the proposed ADAS more efficiently than with a traditional Cloud setup.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.4
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• pp.251-262
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• 1994

The speed of vertical migration and the volume backscattering strength of the scattering layers during the evening and morning transitions between day and night were measured in November 1990-1992 in thermally stratified waters of the East China Sea. Acoustical measurements were carried out using a scientific echo-sounder operating at t재 frequencies of 25 and 100kHz, and using an echo-integration system connected with a micro-computer. Biological sampling was accomplished by bottom trawling to identify fish species recorded on the echo sounder, and the species and length compositions were determined. The values of scattering strength were allocated to group of fishes according to the fish traces on the echo recording paper and the species composition of trawl catches. The vertical velocities of migration derived from the changes in the depths and the values of peak scattering strength of the dense layer vertically migrating toward the bottom or toward the surface. The trawl data suggest that snailfish and fishing frog were the most abundant fishes in all research stations. As sunrise approached, the fish formed a strong concentration just above the thermocline. The the highest values of scattering strength in the entire water column appeared in the depth strata above the thermocline just before the begining of downward migration. As soon as the fish began to migrate downwards across the thermocline, the values of the scattering strength in the depth strata above the thermocline rapidly decreased, while the values for the scattering layer moving slowly toward the bottom gradually increased. During the 1992 surveys, the speed of the vertical migration was estimated to be 0.38m/min in the upward migration and 0.32m/min in the downward migration, respectively. That is the rate of vertical migration was slightly higher at dusk than at dawn. Similar migration patterns were observed on different stations and under different weather conditions during the surveys in 1990.

• The Korean Journal of Applied Statistics
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• v.29 no.3
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• pp.487-503
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• 2016

Urban-to-rural migration for farming has recently emerged as a new way to vitalize rural economies in a fast-aging rural Korea. In this paper, we analyze the 2013 data of returning farmers with statistical network methods. We identify urban to rural migration hubs with centrality measures and find migration trends based on regional clusters with similar features via statistical network models. We also fit a latent distance model to investigate the role of distance in migration.

• Biomolecules & Therapeutics
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• v.22 no.6
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• pp.540-546
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• 2014

The high mortality rates associated with cancer reflect the metastatic spread of tumor cells from the site of their origin. Metastasis, in fact, is the cause of 90% of cancer deaths. Therefore, considerable effort is being made to inhibit metastasis. In the present study, we screened ketotifen for anti-migratory and anti-invasive activities against MDA-MB-231 breast cancer and HT-1080 fibrosarcoma cancer cells. Cancer cell migration and invasion were measured using multi-well chambers. Additionally, western blots were used to examine the effects of ketotifen on the expressions of CDC42, Rho, Rac, and matrix metalloproteinase 9 (MMP-9). The results showed that ketotifen dose-dependently suppressed the migration and invasion of MDA-MB-231 and HT-1080 cells. Ketotifen also suppressed the expressions of CDC42, Rac, and Rho, which, significantly, are involved in MDA-MB-231 and HT-1080 cancer cell migration. Moreover, ketotifen suppressed the expression and activity of MMP-9, which is involved in degradation of the extracellular matrix leading to invasion. The overall data suggested that ketotifen suppresses the migration and invasion of MDA-MB-231 and HT-1080 cancer cells via inhibition of CDC42, Rac, Rho, and MMP-9 expression.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.1
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• pp.63-71
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• 2022

To investigate the short-run effects of social capital on migration decisions of individuals in the rural areas of Vietnam, we conducted dataset mining and performed regression model analysis in the form of panel data. As control variables, we employed the variable of social capital, which is measured by an individual's network, as well as demographic characteristics of individuals and households. We discovered that when a household is in financial distress, social networks such as linkages or asking for aid from others often enhance individual capacity. Individuals with a large social network outside of their immediate area are more inclined to relocate to the location where their connectors live. Individual participation and degree of participation in the organizational community, on the other hand, have little bearing on the likelihood of migration. In addition, this research examines theories and empirical research on the relationship between social capital and migration. Based on our research findings, we have recommended some measures to boost the efficiency of social capital and migration in rural areas of Vietnam through local government solutions.