• Korea journal of population studies
• /
• v.27 no.1
• /
• pp.147-169
• /
• 2004

The paper examines migration and settlement process of the Ulleung Island residents. On the theoretical side, this paper analyzes migration and settlement process of the Ulleung Island residents in relation with a social, cultural, and political phenomenon of that island. And on the methodological side analyzes this paper historical literatures and output materials of field work. In order to achieve the purpose of this study, this paper approaches the issue on three dimensions. First, this article pursues the movement course of the Ulleung Island residents in the early Gaecheokryoung era. Second, it follows up their settlement process. Third, it tries to find out the factors of the population increase and decrease. The findings are as follows: The factors of migration of Ulleung Island residents are following three - first, social and political motive, second, economical motive, and third, criminal motive. The immigrants with these motives have constituted a unique society on the Ulreung Island.

• Corrosion Science and Technology
• /
• v.6 no.2
• /
• pp.50-55
• /
• 2007

The smaller size and higher integration of advanced electronic package systems result in severe electrochemical reliability issues in microelectronic packaging due to higher electric field under high temperature and humidity conditions. Under these harsh conditions, electronic components respond to applied voltages by electrochemical ionization of metal and the formation of a filament, which leads to short-circuit failure of an electronic component, which is termed electrochemical migration. This work aims to evaluate electrochemical migration susceptibility of the pure Sn, Sn-3.5Ag, Sn-3.0Ag-0.5Cu solder alloys in $Na_{2}SO_{4}$. The water drop test was performed to understand the failure mechanism in a pad patterned solder alloy. The polarization test and anodic dissolution test were performed, and ionic species and concentration were analyzed. Ag and Cu additions increased the time to failure of Pb-free solder in 0.001 wt% $Na_{2}SO_{4}$ solution at room temperature and the dendrite was mainly composed of Sn regardless of the solders. In the case of SnAg solders, when Ag and Cu added to the solders, Ag and Cu improved the passivation behavior and pitting corrosion resistance and formed inert intermetallic compounds and thus the dissolution of Ag and Cu was suppressed; only Sn was dissolved. If ionic species is mainly Sn ion, dissolution content than cathodic deposition efficiency will affect the composition of the dendrite. Therefore, Ag and Cu additions improve the electrochemical migration resistance of SnAg and SnAgCu solders.

• Journal of the Korea Convergence Society
• /
• v.12 no.2
• /
• pp.221-231
• /
• 2021

This paper identify factors of migration of employees' household who work for relocated public institutions. As a factors of migration, we consider individual and household characteristics, the gravity model of distance and population and so on. Considering discrete dependant variable and structure of data, we employ the logistic multilevel model and random intercept model. The result indicates employees' who are female, 30s and 40s, higher education level(PhD) and whose spouse are unemployed tend to transfer their residential registration to new city near relocated public institution. Regarding regional variable, the distance from employee's previous residential location and number of migration of prior year are statistically significant. Also the model indicate regional economy, educational and residential environment of new city influence employee's decision for transferring residential registration.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.6
• /
• pp.1892-1912
• /
• 2022

With the massive demand and growth of cloud computing, virtualization plays an important role in providing services to end-users efficiently. However, with the increase in services over Cloud Computing, it is becoming more challenging to manage and run multiple Virtual Machines (VMs) in Cloud Computing because of excessive power consumption. It is thus important to overcome these challenges by adopting an efficient technique to manage and monitor the status of VMs in a cloud environment. Reduction of power/energy consumption can be done by managing VMs more effectively in the datacenters of the cloud environment by switching between the active and inactive states of a VM. As a result, energy consumption reduces carbon emissions, leading to green cloud computing. The proposed Efficient Dynamic VM Scheduling approach minimizes Service Level Agreement (SLA) violations and manages VM migration by lowering the energy consumption effectively along with the balanced load. In the proposed work, VM Scheduling for Efficient Dynamically Migrated VM (VMS-EDMVM) approach first detects the over-utilized host using the Modified Weighted Linear Regression (MWLR) algorithm and along with the dynamic utilization model for an underutilized host. Maximum Power Reduction and Reduced Time (MPRRT) approach has been developed for the VM selection followed by a two-phase Best-Fit CPU, BW (BFCB) VM Scheduling mechanism which is simulated in CloudSim based on the adaptive utilization threshold base. The proposed work achieved a Power consumption of 108.45 kWh, and the total SLA violation was 0.1%. The VM migration count was reduced to 2,202 times, revealing better performance as compared to other methods mentioned in this paper.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.4 s.97
• /
• pp.110-115
• /
• 1999

The surface gloss of an injection molded part is one of the most significant point for evaluating the quality of products appearance. The effects of process condition on the gloss of ABS(Acrylonitrile-Butadiene-Styrene) molded part were investigated in this work. The measurements of gloss and morphology on the surface of molded part were carried out with different melt temperature, mold temperature, mold surface roughness, injection pressure and holding pressure. Gloss had a maximum value with melt temperature in the range of 210 to 220 ${^\circ}C$ and with mold temperature 40 to 50${^\circ}C$ and with injection pressure 80~90 MPa, respectively. Melt temperature was shown to have the largest effect on gloss in our work. Gloss was not improved in the region of melt temperature 240${^\circ}C$ above and of mold temperature 60${^\circ}C$ above. It was concluded that the variation of gloss was mainly caused by rubber particles migration under shear stress not by their aggregation or necklace.

• Journal of Korean Society of Rural Planning
• /
• v.12 no.2 s.31
• /
• pp.37-47
• /
• 2006

Recently, due to the growing concern of the public in rural amenities and hobby farming works, much more urbanites, especially near-retirees, have been interested in rural life style than before. However, in spite of popular preference to ruralities, little has been known about their demand on retired rural life. Therefore, this study examined urbanites' attitude to preparatory works for out-migration, preferred residential site conditions and life style in the countryside. For this purpose, data were collected from a survey with the sample of 386 urban residents aged 40 to 65 rho hoped moving into the countryside after retirement, through structured questionnaires. Descriptive statistical works were performed using SPSS/PC windows program. The major findings of this study were as follows; (1) Host of urbanites, who answered in this study, planned to prepare ex-urban movement in their fifties and to put into practice in their sixties. (2) Key factors of location decision on movement were proximity/accessibility to centre city, medical service level, and distance to their family or friends. And about a half of respondents wanted second home in the countryside. (3) Most favoured rural life styles were nature-friendly well-being and hobby/healthy firming. Generally, the respondents of this survey had the positive attitude to do works in their later life, especially preferred to farming and volunteering in their communities.

• Journal of Internet Computing and Services
• /
• v.24 no.2
• /
• pp.1-10
• /
• 2023

The Multi-access Edge Computing (MEC) paradigm equips network edge telecommunication infrastructure with cloud computing resources. It seeks to transform the edge into an IT services platform for hosting resource-intensive and delay-stringent services for mobile users, thereby significantly enhancing perceived service quality of experience. However, erratic user mobility impedes seamless service continuity as well as satisfying delay-stringent service requirements, especially as users roam farther away from the serving MEC resource, which deteriorates quality of experience. This work proposes a deep reinforcement learning based service mobility management approach for ensuring seamless migration of service instances along user mobility. The proposed approach focuses on the problem of selecting the optimal MEC resource to host services for high mobility users, thereby reducing service migration rejection rate and enhancing service availability. Efficacy of the proposed approach is confirmed through simulation experiments, where results show that on average, the proposed scheme reduces service delay by 8%, task computing time by 36%, and migration rejection rate by more than 90%, when comparing to a baseline scheme.

• Journal of Agricultural Extension & Community Development
• /
• v.19 no.1
• /
• pp.29-48
• /
• 2012

Many of the urban people wish to move to rural area to avoid urban problems like pollution, crowdedness, crime and after their retirement. The purpose of this study was to analyse of adaptation of inmigration in rural community. For this purpose, data were collected from 239 migrations to rural area. The major findings of this study are as follows: 1) 32.0% of respondents wished to move to rural area that they were expected for countryside life, 2) 68.1% of respondents had experience to visit farmer's house 3) 49.5% of respondents agreed to rural community person is good 4) many person of migration to rural area(74.5%) have the idea that they should be active participation for community volunteer work 5) migration people was wanted to take care of them by natives in rural community on the lonely time.

• Journal of the Microelectronics and Packaging Society
• /
• v.13 no.3 s.40
• /
• pp.1-8
• /
• 2006

Higher density integration and adoption of new materials in advanced electronic package systems result in severe electrochemical reliability issues in microelectronic packaging due to higher electric field under high temperature and humidity conditions. Under these harsh conditions, metal interconnects respond to applied voltages by electrochemical ionization and conductive filament formation, which leads to short-circuit failure of the electronic package. In this work, in-situ water drop test and evaluation of corrosion characteristics for SnPb solder alloys in D.I. water and NaCl solutions were carried out to understand the fundamental electrochemical migration characteristics and to correlate each other. It was revealed that electrochemical migration behavior of SnPb solder alloys was closely related to the corrosion characteristics, and Pb was primarily ionized in both D.I. water and $Cl^{-}$ solutions. The quality of passive film formed at film surface seems to be critical not only for corrosion resistance but also for ECM resistance of solder alloys.

• Journal of the Korean Society of Child Welfare
• /
• no.58
• /
• pp.231-262
• /
• 2017

South Korea has long been a culturally homogenous society, yet the increasing number of immigrants has turned the country into a multicultural society. Therefore, many empirical studies have investigated the way immigrants adapt to the Korean society and its associated factors. However, examining the overall process of migration (from family separation to reunification and cultural adaptation to the host society) that immigrant youth usually experience has been understudied. Previous empirical research and theoretical work have identified prominent factors that predict immigrant youth's mental health: experiences of family separation, living with others rather than primary caretakers during the separation, the length of residency in the host society, and family and peer support. In this respect, this exploratory and preliminary study that examined whether the experience of migration process and post-migration are related to Korean immigrant youth's mental health problems (depression, anxiety, and suicidal ideation). The result indicated that longer duration of family separation; living with relatives, siblings; and friends rather than primary caretakers during the separation; receiving less support from family and peer after migration; and a lower degree of cultural adaptation to Korean culture were associated with depression, anxiety, and suicidal ideation. Drawing upon the results, this study discussed implications for policy and practice.