• IEMEK Journal of Embedded Systems and Applications
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• v.9 no.4
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• pp.205-210
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• 2014

Cache based live migration method utilizes a cache, which is accessible to both side (remote and local), to reduce the virtual machine migration time, by transferring only irredundant data. However, address space layout randomization (ASLR) is proved to reduce the memory duplicate ratio between targeted migration memory and the migration cache. In this pager, we analyzed the behavior of ASLR to find out how it changes the physical memory contents of virtual machines. We found that among six virtual memory regions, only the modification to stack influences the page-level memory duplicate ratio. Experiments showed that: (1) the ASLR does not shift the heap region in sub-page level; (2) the stack reduces the duplicate page size among VMs which performed input replay around 40MB, when ASLR was enabled; (3) the size of memory pages, which can be reconstructed from the fresh booted up state, also reduces by about 60MB by ASLR. With those observations, when applying cache-based migration method, we can omit the stack region. While for other five regions, even a coarse page-level redundancy data detecting method can figure out most of the duplicate memory contents.

• Journal of Korean Society of Rural Planning
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• v.28 no.4
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• pp.1-9
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• 2022

Rural decline due to the decrease of the local population is an inevitable phenomenon, and a vicious cycle has been formed between a lack of basic living services and a population decrease in rural areas. Therefore, the study aims to derive the migration decision-making characteristics based on basic living service infrastructure data in rural areas. To do this, the population change over the past 20 years was categorized into six types, and the relationship between the classified population change types and the number of basic living service infrastructures was analyzed using decision tree analysis. Of the total 3,501 regions, 801 regions were the continuous decline type, of which 740 were rural areas. On the other hand, among 569 regions that were the continuous increase type, 401 regions were urban areas, confirming the population imbalance between rural and urban areas. As a result of the decision tree analysis on the relationship between population change types and the distribution of basic living service infrastructure, the number of daycare centers was derived as an important variable to classify the continuous increase type. Hospitals, parks, and public transportation were also found to be major basic living services affecting the classification of population change types.

• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.503-517
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• 2010

Service-oriented computing, the effective paradigm for developing service applications by using reusable services, becomes popular. In service-oriented computing, service consumer has no responsibility for managing services, just invokes services what service providers are producing. On the other hand, service providers should manage any resources and data for service consumers can use the service anytime and anywhere. However, it is hard service providers manage the quality of the services because an unspecified number of service consumers. Therefore, service scalability for providing services with higher quality of services specified in a service level agreement becomes a potential problem in service-oriented computing. There have been many researches for scalability in network, database, and distributed computing area. But a research about a definition of service scalability and metrics of measuring service scalability is still not mature in service engineering area. In this paper, we construct a service network which connects multiple service nodes, and integrate all the resources to manage it. And we also present a service scalability framework for managing service scalability by using a mechanism of service migration or replication. In section 3, we, firstly, present the structure of the scalability management framework and basic functionalities. In section 4, we propose scalability enhancement mechanism which is needed to release functionality of the framework. In section 5, we design and implement the framework by using proposed mechanism. In section 6, we demonstrate the result of our case study which dynamically manages services in multi-nodes environment by applying our framework. Through the case study, we show the applicability of our scalability management framework and mechanism.

• Journal of Korea Spatial Information System Society
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• v.9 no.1
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• pp.91-104
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• 2007

In ubiquitous computing environment, people expect services to change actively in response to the change of themselves and surrounding environment. In order to meet such expectations, the streaming service needs technologies for migrating through various devices, following the user's movement, and the technology of individualized streaming push service. In this paper, we designed and implemented U-Stream, a ubiquitous streaming service system, based on user-defined context and stream view. The system classifies contexts according to streaming service migration and allows users to define some contexts and, by doing so, provides user-oriented individualized services rather than uniform services based solely on the developers' anticipations.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.3
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• pp.67-74
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• 2010

The aim of this paper is to come up with a methodology of migration for current transportation digital map in order to construct NDRM, which is the most essential map data for car navigation system. The model suggested through our study is able to efficiently produce navigable service map for route finding and guidance as well as to make the best of general road network developed by KOTI.

• Korea journal of population studies
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• v.17 no.2
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• pp.1-20
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• 1994

The main purpose of this paper is to examine changes in internal migration patterns during 1960 - 1990 period, and to analyze population movement to and from the Capital Region. The overall mobility rate of the whole Korean population has heen increasing since the 1960s, and reached to 24.6% in 1985 - 90 period. The most interesting changes in the migration pattern is that Seoul lost its population through migration during 1985 - 90, mainly due to heavy outmigration to Kyonggi province. The analysis of characteristics of inmigrants to the Capital Region reveals that those moved to Seoul are more likely to be young, better educated, never married and engage in service sector in comparison with migrants moved to the suburban districts and the outlying Kyonggi province. However, on the whole migrants moved to the Capital Region are overrepresented in manufacturing sector, which suggests that more effective policy measures to control the growth of manufacturing sector in the Capital Region is called for.

• The Southeast Asian review
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• v.28 no.3
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• pp.111-158
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• 2018

This paper pays attention to the recent increase of young Koreans working in the low-skilled service sector in Singapore. Such rapid increase largely results from the Korean government's initiatives to promote labour migration of young people and the concurrent proliferation of migration agencies, against the background of growing youth unemployment in South Korea. By exploring the motivations and trajectories of young people's labour migration to Singapore, this study examines to what extent they think their expectations have been met and how they interpret their migration and work experiences. There has been little research that examines the actual voices of young migrants as part of migration studies, whilst the majority of previous research focuses on the evaluation of government support programmes based on job matching rates, surveys of participant satisfaction and etc. Young people who went to Singapore to improve their English language skills and qualifications for future employment in Korea have become frustrated due to low-skilled service jobs that consist of low pay and high labour intensity. Their credentials are devalued and they experience deskilling through this migration process. Most of them were discontent with the Korean migration agencies they used and critical about programmes offered by government institutions and universities/colleges. Despite being subject to deskilling, they did try to actively cope or resist this situation. This study focuses on the various ways these migrants attempted to manage the gap between their initial expectations and reality. It also demonstrates how these migrants interpreted their work experiences after returning to Korea: whilst most of them did not cash off their Singapore work experience for a decent job after returning to Korea, they did not define their experience as a complete failure. Adding to cultural, social capital they gained through this experience, they acquired 'mobility capital' which includes confidence, the desire to move, and capacity to control one's own movement.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.201-210
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• 2014

Recently, the more complicated with the elements made of information system, the more dangerous in migration them. So it is need to accomplish information system migration systematically. According to the movement of public institution, a large scale of information system migration is in processing and will be made. In this paper, I would like to suggest the use of migration solution in order to speed & effect information system migration process. This will be provided the pursuit function of information system movement, movement location pursuit in real time, monitoring function through the situation room, separation migration possibility on the basis of business attribute. Therefore, if you use the suggested solution, it will be decreased trial and error & minimized the movement time.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.29 no.7
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• pp.61-70
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• 2011

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.1
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• pp.169-176
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• 2014

According to explosion of smart-devices, demands on N-screen services based on cooperation of multiple screens are rapidly increasing. These N-screen services can provide new user-experience (UX) to users. That is, it can provide technical advances to users. On the other hand, it causes new security problems. In this paper, we analyze conventional web-security attacks, and we propose and analyze new security requirements for migration, combination, and separation of web-contents based on N-screen service scenarios. Also, we develop N-screen cooperation service framework in order to ensure user security.