• Title/Summary/Keyword: migration process

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Improved Relocation Accuracy by Adding Extended Search in Sink Migration Process of WSN (WSN 환경의 싱크 재배치 과정에서 영역 확장 검색 추가를 통한 재배치 정확성 향상)

  • Lee, Tae-Ho;Yoo, Seung-Eon;Lee, Byung-Jun;Kim, Kyung-Tae;You, Hee-Yong
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2019.01a
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    • pp.105-106
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    • 2019
  • 본 논문에서는 무선 센서 네트워크(Wireless Sensor Network, WSN) 환경에 배치되어 물리적 데이터를 감지하는 각 센서들의 데이터를 수집을 위한 싱크(Sink)가 일정 주기로 이동 및 재배치되는 싱크 마이그레이션(Migration) 과정에 있어 다음 배치 위치를 효율적으로 선정하기 위해 클러스터 헤드(Cluster Head, CH)를 기준으로 영역 검색 단계를 추가하여 재배치 정확성 및 효율성 증대 기법을 제안한다. 본 논문에서는 WSN 환경을 바탕으로 싱크 재배치 과정에 해당 기법을 적용하여 시뮬레이션 하였으며, 해당 실험의 결과에 따르면 싱크 재배치의 정확성 및 효율성 증대로 전체 영역에 대한 고른 데이터 수집 및 소모 에너지 균형이 향상되었다.

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A Study About Radionuclides Migration Behavior in Terms of Solubility at Gyeongju Low- and Intermediate-Level Radioactive Waste (LILW) Repository

  • Park, Sang June;Byon, Jihyang;Lee, Jun-Yeop;Ahn, Seokyoung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.1
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    • pp.113-121
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    • 2021
  • A safety assessment of radioactive waste repositories is a mandatory requirement process because there are possible radiological hazards owing to radionuclide migration from radioactive waste to the biosphere. For a reliable safety assessment, it is important to establish a parameter database that reflects the site-specific characteristics of the disposal facility and repository site. From this perspective, solubility, a major geochemical parameter, has been chosen as an important parameter for modeling the migration behavior of radionuclides. The solubilities were derived for Am, Ni, Tc, and U, which were major radionuclides in this study, and on-site groundwater data reflecting the operational conditions of the Gyeongju low and intermediate level radioactive waste (LILW) repository were applied to reflect the site-specific characteristics. The radiation dose was derived by applying the solubility and radionuclide inventory data to the RESRAD-OFFSITE code, and sensitivity analysis of the dose according to the solubility variation was performed. As a result, owing to the low amount of radionuclide inventory, the dose variation was insignificant. The derived solubility can be used as the main input data for the safety assessment of the Gyeongju LILW repository in the future.

Construction Process of Gender in the Biographies of Migrant Women -Based on the Biographies of the Korean female Migrant Workers in Germany- (이주여성의 생애사에 재현된 젠더의 구성과정 -재독한인여성의 생애사를 중심으로-)

  • Yang, Yeung-Ja
    • Korean Journal of Social Welfare
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    • v.64 no.2
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    • pp.325-354
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    • 2012
  • The current research intends to analyse the construction process of gender in the biographies of migrant women. Ten autobiographical-narrative interviews with Korean female migrant workers in Germany were conducted and the following conclusions were ascertained through the analysis of Schutze's autobiographical-narrative interview: The genders in their biographies were constructed similar before their marriage, but different after their marriage according to the work-family balanced type and the family centered type. Before their migration the 'process of life' as female high school students and female workers showed that both types had partially deconstructed a sex-segregated gender. The process of life as female migrant workers after their migration showed that both types had partially constructed a sex-neutral gender. The process of life after their marriage exhibited that the former strengthened and strengthens a sex-neutral gender in a double position as female migrant workers and female marriage migrants, but the latter reconstructed a sex-segregated gender again and intensifies this in a process of time. Based on these results, some implications for the social work practice were addressed, which emerged from the understanding on the gender in the biographies of migrant women.

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A Study on the Migration of the Berbers in France and their Current Status (프랑스 내 '베르베르인'의 이민 과정과 그 위상에 관한 연구)

  • Lim, Gi-Dae
    • Cross-Cultural Studies
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    • v.42
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    • pp.131-163
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    • 2016
  • The issue of migrants has always been a social problem in France. Particularly, migration issues from the Maghreb region to multicultural France are recognized as topics of confrontation and conflict. One of the many reasons would be that the Maghreb migrant issue is interpreted with a hostile or conflicting 'Arab-Islam' meaning in the West. Therefore, the naming of natives from this region as 'Arab-Maghrebis' has become a common phenomenon. However, deeper understanding of the Maghreb region will explain that such naming could produce a number of problems. This is because the native Maghrebis, not only in the Maghreb region but also in France, are Berbers. Among the various Berbers, the Kabyles are in many ways different from the Arabs in their language, culture, and way of thinking. Apart from the difference in their lifestyle, there is a deep anti-Arab sentiment within them that represents their resistance against the hundreds-of-years Arab domination. This feature has also been used as France's tool of colonial division policy during the colonization period. The purpose of this study is to discuss the settlement process of the Kabyles in France by paying attention to their features. The Kabyles were the first to migrate to France among the natives of the Maghreb region. This study focuses on the process of their migration and search for identity, as well as how they continued to form community and the Berber's cultural movement. Through these series of processes, it is possible to point out the fictitious claim in France and in Korea that Maghrebis are Arab-Muslims. Lastly, the current use of Berber language in France and Algeria is not a coincidental phenomenon, rather it has a connection with the prolonged cultural movement and the settlement process of the migrants in France.

Change of Hydraulic Properties of Sand due to Fine Diatom Particle Migration (미세 Diatom 입자 이동에 의한 모래지반의 투수 특성 변화)

  • Pyo, Won-Mi;Lee, Jong-Sub;Lee, Joo Yong;Hong, Won-Taek
    • Journal of the Korean Geotechnical Society
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    • v.34 no.2
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    • pp.19-32
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    • 2018
  • During the process of gas hydrate extraction in the deep seabed, fine diatom particle migration occurs, which causes the seabed slope failure and the productivity deterioration of the gas hydrate. Therefore, a study related with the changes of the ground characteristics due to the fine particle migration is required. The objective of this study is to investigate the change of hydraulic properties of sand due to the migration of fine diatom particle in sandy soils. In order to simulate the sediments of the Ulleung basin gas hydrate in the East Sea, fifteen sand-diatom mixtures that have different diatom volume fractions (DVF) are prepared. During the falling head permeability tests, the coefficients of permeability are measured according to the DVF. In addition, for the simulation of the fine diatom particle migration, constant head permeability tests are conducted by applying the hydraulic pressures of 3 kPa, 6kPa, and 9 kPa on a specimen composed of two layers: a specimen with 50% DVF in upper layer and a specimen with 0% DVF in lower layer. Furthermore, the coefficient of permeability and the electrical resistivity of the migration zone are measured during the constant head permeability test. The falling head permeability tests show that the coefficient of permeability decreases as the DVF of the specimen increases. In addition, the gradient of the coefficient of permeability curve decreases in the DVF range of 10%~50% compared with that of 0%~10%, and increases above 50% in DVF. The result of constant head permeability tests shows that the coefficient of permeability decreases and electrical resistivity increases in the migration zone due to the fine diatom particle migration. This study demonstrates that fine diatom particle migration reduces the permeability of the soils and the behavior of the migration zone due to the fine diatom particle migration may be estimated based on the reversal relationship between the coefficient of permeability and the electrical resistivity.

Developmental Anomalies of Central Nervous System in Human

  • Chi, Je G.
    • Toxicological Research
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    • v.17
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    • pp.11-16
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    • 2001
  • The development of the central nervous system is a continuous process during the embryonic and fetal periods. For a better understanding of congenital anomalies of central nervous system, three major events of normal development, i.e., neurulation (3 to 4 weeks), brain vesicle formation (4 to 7 weeks) and mantle formation (over 8 weeks) should be kept in mind. The first category of anomalies is neural tube defect. Neural tube defects encompass all the anomalies arise in completion of neurulation. The second category of central nervous system anomalies is disorders of brain vesicle formation. This is anomaly that applies for "the face predicts the brain". Holoprosencephaly covers a spectrum of anomalies of intracranial and midfacial development which result from incomplete development and septation of midline structures within the forebrain or prosencephalon. The last category of central nervous system malformation is disorders involving the process of mantle formation. In the human, neurons are generated in two bursts, the first from 8 to 10 weeks and next from 12 to 14 weeks. By 16 weeks, most of the neurons have been generated and have started their migration into the cortex. Mechanism of migration disorders are multifactorial. Abnormal migration into the cortex, abnormal neurons, faulty neural growth within the cortex, unstable pial-glial border, degeneration of neurons, neural death by exogenous factors are some of the proposed mechanism. Agyria-pachygyria are characterized by a four-layerd cortex. Polymicrogyria is gyri that are too numerous and too small, and is morphologically heterogeneous. Cortical dysplasia is characterized by the presence Q[ abnormal neurons and glia arranged abnormally in focal areas of the cerebral cortex. Neuroglial malformative lesions associated with medically intractable epilepsy are hamartia or hamartoma, focal cortical dysplasia and microdysgenesis.ysgenesis.

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Migration Agent for Seamless Virtual Environment System in Cloud Computing Network (클라우드 컴퓨팅 네트워크에서 Seamless 가상 환경 시스템 구축을 위한 마이그레이션 에이전트)

  • Won, Dong Hyun;An, Dong Un
    • Smart Media Journal
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    • v.8 no.3
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    • pp.41-46
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    • 2019
  • In a MMORPG, a typical application of virtual environment systems, it is a common desire to play in a more realistic environment. However, it is very difficult to provide a latency-free virtual environment to a large user base, mainly due to the fact that the real environment must be configured on multiple servers rather than on single server and that data must be shared on the real server when users move from one region to another. Experiencing response delays continuously in the process of information synchronization between servers greatly deteriorates the degree of immersion. In order to solve this problem, it is necessary to minimize the response delay occurring in the information synchronization process between the servers. In this paper, we propose Migration Agent for efficient information synchronization between field servers providing information of virtual environment and minimizing response delay between Field Server and PC(Player Character) and implement it in cloud computing network. In the proposed system, CPU utilization of field server increased by 6 ~ 13%, and response time decreased by 5 ~ 10 seconds over the existing system in 70,000 ~ 90,000 PCs

Methane Oxidation in Landfill Cover Soils: A Review

  • Abushammala, Mohammed F.M.;Basri, Noor Ezlin Ahmad;Irwan, Dani;Younes, Mohammad K.
    • Asian Journal of Atmospheric Environment
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    • v.8 no.1
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    • pp.1-14
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    • 2014
  • Migration of methane ($CH_4$) gas from landfills to the surrounding environment negatively affects both humankind and the environment. It is therefore essential to develop management techniques to reduce $CH_4$ emissions from landfills to minimize global warming and to reduce the human risks associated with $CH_4$ gas migration. Oxidation of $CH_4$ in landfill cover soil is the most important strategy for $CH_4$ emissions mitigation. $CH_4$ oxidation occurs naturally in landfill cover soils due to the abundance of methanotrophic bacteria. However, the activities of these bacteria are influenced by several controlling factors. This study attempts to review the important issues associated with the $CH_4$ oxidation process in landfill cover soils. The $CH_4$ oxidation process is highly sensitive to environmental factors and cover soil properties. The comparison of various biotic system techniques indicated that each technique has unique advantages and disadvantages, and the choice of the best technique for a specific application depends on economic constraints, treatment efficiency and landfill operations.

Behavior of Hydroxide Ions at the Water-Ice Surface by Low Energy Sputtering Method

  • Kim, S.Y.;Park, E.H.;Kang, H.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.338-338
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    • 2011
  • The behavior of hydroxide ions on water-ice films was studied by using $Cs^+$ reactive ion scattering (RIS), low energy sputtering (LES) and temperature-programmed desorption (TPD). A $Cs^+$ beam of a low kinetic energy (<100 eV) from $Cs^+$ ion gun was scattered at the film surface, and then $Cs^+$ projectiles pick up the neutral molecules on the surface as $Cs^+$-molecule clusters form (RIS process). In LES process, the preexisting ions on the surface are desorbed by the $Cs^+$ beam impact. The water-ice films made of a thick (>50 BL) $H_2$O layer and a thin $D_2O$ overlayer were controlled in temperatures 90~140K. We prepared hydroxide ions by using Na atoms which proceeded hydrolysis reaction either on the ice film surface or at the interface of the $H_2O$ and $D_2O$ layers.[1] The migration of hydroxide ions from the $H_2O/D_2O$ interface to the top of the film was examined as afunction of time. From this experiment, we show that hydroxide ions tend to reside at the water-ice surface. We also investigated the H/D exchange reactions of $H_2O$ and $D_2O$ molecules mediated by hydroxide ions to reveal the mechanism of migration of hydroxide to the ice surface.

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