• Journal of Communications and Networks
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• v.1 no.2
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• pp.134-142
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• 1999

We have developed fully functional Video Server and Client applications which can transmit, receive, decompress and display compressed video over various networks. Our video trans-port allows dynamic rate control feedback, loss detection, and repair requests from Clients to the Server. Our experiments show how feedvack-before-degradation scheme for rate adaptation maintains good display frame-rate for video playback. We show how the playback degradation(reduction in display frame-rate) oc-curs and what happens if corrective measures are not taken to im-prove the situation. The degradation is attributed to the increased internal kernel buffering which consumes scarce CPU resources. We demontrate with our experimental results that ServerNet, with improved hardware delivery guarantees, can significantly reduce host CPU resource consumption while serving video streams. We present the maximum number of streams which can be served for each of ATM and ServerNet interconnects. The appropriate user-level packet size for the video server are also determined for each case.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.25-28
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• 2008

An aerodynamic calculation in hover of KUH main rotor blade is performed using a three-dimensional unstructured hybrid mesh viscous flow solver. The flow solver utilizes a vertex-centered finite-volume scheme that is based on the Roe's flux-difference splitting with an implicit Jacobi/Gauss-Seidel time integration. The eddy viscosity are estimated by the Spalart-Allmaras one-equation turbulence model. A solution-adaptive mesh refinement technique is used for efficient capturing of the tip vortex. Calculations are performed at several operating conditions with varying collective pitch setting for KUH main rotor blade in hover. Good agreements are obtained between the present and other results using HOST and CAMRAD II in overall rotor performance. It is demonstrated that the present vertex-centered flow solver is an efficient and accurate tool for the assessment of rotor performance in hover.

• Mycobiology
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• v.39 no.3
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• pp.143-150
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• 2011

The basidiomycete fungus Cryptococcus neoformans is an important pathogen of immunocompromised people. The ability of the fungus to sense its environment is critical for proliferation and the generation of infectious propagules, as well as for adaptation to the mammalian host during infection. The conserved cAMP/protein kinase A pathway makes an important contribution to sensing, as demonstrated by the phenotypes of mutants with pathway defects. These phenotypes include loss of the ability to mate and to elaborate the key virulence factors capsule and melanin. This review summarizes recent work that reveals new targets of the pathway, new phenotypic consequences of signaling defects, and a more detailed understanding of connections with other aspects of cryptococcal biology including iron regulation, pH sensing, and stress.

• Journal of the Korean association of regional geographers
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• v.22 no.1
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• pp.180-194
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• 2016

The local identity of a female marriage migrant is not fixed to certain boundary or location, but rather comprised flexibly according to geographical movement or new settlement to different place. This research focuses on the local identity and life change of female marriage migrants that are constituted/reconstituted according to spatial transition, or migration. The analysis was conducted to find out traits of changes in the periods of migration and settlement based on the following categorization: multiculturalism and bicultural identity, assimilation and host country identity, exclusion and origin country identity, marginalization and marginal identity. The results are as follows; while having identical experience in terms of a migration, the local identities of marriage migrant women differed according to individual/regional characteristics as well as their respective roles within those traits. In addition, most of females showed passivity in maintaining and exposing their cultural identities of original states. Moreover the life satisfaction change of female marriage migrant that is type of assililation and host country identity is appeared more than others. through this assimilation and accommodation mean adaptation to female marriage migrant lived in Korea. However the intercultural competences of both marriage migrant woman and children in multicultural families facilitate the connection among different cultures. Based on these outcomes, with the transition to multicultural society and space, this research proposes the necessity of fostering global citizenship for mutual recognition of each culture, thus enabling coexistence.

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

• Journal of Environmental Science International
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• v.23 no.6
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• pp.1121-1130
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• 2014

This study aims to find the perception and utilization of the citizen about the dryness watch warning (DWW) among special weather reports. For this we have made up a descriptive questionnaire including the perception, utilization of special weather reports. Using the SPSS 17.0 program, descriptive statistics, t-test, ANOVA and Scheffe test were used to analyze the collected data. The results are as follows; The perception of DWW is measured by 4 point Likert scale and the average is $15.97{\pm}3.70$ (percentile=57.0). This value shows that the awareness level is not that high and according to the occupation, college students show the lowest awareness and housewives show the highest awareness. According to the age, the teens and twenties show the lowest awareness and fifties and sixties show the highest awareness. Although the perception of the teens and college students are rather poor, there were many positive answers that it is necessary to establish the advanced disaster prevention plan according to the questionnaire about the utilization of DWW. Therefore, if we come up with an effective plan to improve the perception than we can expect a large-effect in terms of fire and forest fire prevention. The perception of DWW can be improved by providing weather information and weather related education program on TV or internet which have the high level of preference. Also, it is necessary to provide online and offline program of advertising education and disaster management education through the weather forecast bureau which is the host organization of delivering weather information.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.342-342
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• 2017

Rice seeds are a home to endophytic bacterial communities which serve as a source of the plant's endophytes. As rice undergo physiological and adaptive modifications through cross breeding in the process of attaining salinity tolerance, this may also lead to changes in the endophytic bacterial community especially those residing in the seeds. This study explores the community structure of seed bacterial endophytes as influenced by rice parental lineage, genotype and physiological adaptation to salinity stress. Endophytic bacterial diversity was studied through culture dependent technique, cloning and Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed considerably diverse communities of bacterial endophytes in the interior of rice seeds. The richness of ribotypes ranges from 5-14 T-RFs corresponding to major groups of bacterial endophytes in the seeds. Endophytic bacterial diversity of the salt-sensitive IR29 is significantly more diverse compared to those of salt-tolerant cultivars. Proteobacteria followed by Actinobacteria and Firmicutes dominated the overall endophytic bacterial communities of the indica rice seeds based on 16S rDNA analysis of clones and isolates. Community profiles show common ribotypes found in all cultivars of the indica subspecies representing potential core microbiota belonging to Curtobacterium, Flavobacterium, Enterobacter, Xanthomonas, Herbaspirillum, Microbacterium and Stenotrophomonas. Multivariate analysis showed that the bacterial endophytic community and diversity of rice seeds are mainly influenced by their host's genotype, physiological adaptation to salt stress and parental lineage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.1B
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• pp.39-46
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• 2005

As the multimedia application traffic takes more portion in the internet traffic, it is necessary to control the network congestion through the congestion control protocol. In addition, the QoS-enabled networks such as DiffServ become an indispensable technology when running the multimedia applications. However, the previously proposed end-to-end congestion control algorithms take the round trip time to react the network congestion. Thus, as the RTT becomes larger, the reaction against the congestion gets delayed further, while the network congestion gets worse. In addition the performance of end-to-end congestion control algorithm is degraded if the QoS-enabled network runs the congestion control mechanism in the network level without any coordination between them. In this paper, we propose the early rate adaptation protocol for the DiffServ network which effectively linke the congestion control algorithm at the host and the congestion mechanism in the network together. By taking advantage of early congestion notification from the network it is possible to react the network congestion more quickly and effectively.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.6
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• pp.26-36
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• 2009

ad-hoc network is self-constructed by mobile hosts without any infrastructure. And the hosts collaborate with each other for routing packet by means of multi-hop communication. But it is too hard to deploy ad hoc network at the large area because of the salability problem caused by low network throughput. network throughput decrease is due to contention on the air among the neighbor host and single interface limitation, and broadcast flooding through overall network. In this paper, to solve the ad hoc scalability problem, we propose mesh network based scalable hierarchical ad hoc architecture, and also propose the adaptation methods for inter-working with the host not including ad hoc functions and the legacy infra-network.

• Korean Journal of Ichthyology
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• v.17 no.2
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• pp.105-111
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• 2005

Most of the eggs and (or) pre-larvae of Acheilognathus signifer were observed from the gills of Unio douglasiae sinuolatus, 30~45 mm in the shell length, that is the host mussel of A. signifer. There was no selectivity in proportion to mussel size at the range observed. One to seven individual eggs and (or) pre-larvae were found in the mussels, with a mean of 2.5 individuals, and the rate of possessing one egg and (or) pre-larva was 50.0%. When the prelarva of A. signifer acquired swimming ability inside the mussel, it moved into the suprabranchial chamber. It was estimated that the growth period was 4~6 weeks. The minute tubercles of the pre-larvae were observed immediately after hatching. Absorption of the minute tubercles was observed starting the 7 th day, with most of tubercles absorbed 13 days after hatching and completed 20 days after the yolk was entirely absorbed.