• Title/Summary/Keyword: Cellular association

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Distributed Self-Organized Cell Association for Heterogeneous Cellular Networks (이기종 셀룰러 네트워크에서의 분산 자기 구성 셀 접속 기법)

  • Lee, Hyung Yeol;Lee, Jinnyeong;Park, Jin Bae;Ko, Byung Hoon;Kim, Kwang Soon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.5
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    • pp.812-814
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    • 2015
  • In this letter, a distributed self-organized cell association scheme is proposed for heterogeneous cellular networks. In which each small cell uses a common self-organization strategy and takes its environment into account to establish its own cell association scheme. It is confirmed that the proposed cell association improves the user throughput and areal spectral efficiency compared to joint association.

General Strain Theory approach to the Use of Cellular Phone Dependence of Middle School Students (일반긴장이론(GST)을 이용한 중학생의 휴대폰 의존에 미치는 영향)

  • Shim, Hyun-Jin;Lee, Il-Hyun;Rhee, Hyun-Sill
    • The Journal of the Korea Contents Association
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    • v.14 no.2
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    • pp.355-363
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    • 2014
  • The purpose of this study is to find out the effect of using cellular phone dependence of middle school student based on Agnew's GST. A total of 2,151 questionnaires were used to Korean Children and Youth Panel Survey(KCYPS)2010. Analytical methods of Structural Equation Model(SEM) was verified by AMOS 21.0 Ver. The results were the following. Firstly, The fit of definitive model was $X^2=1398.997$, df=144, GFI=.937, NNFI(TLI)=.902, CFI=.918, RMSEA=.061. Model was proper to verify the use of cellular phone dependence of adolescents. Secondly, The strain factors of middle school student presented statistically significant positive effect to make negative life satisfaction. Finally, The negative life satisfaction of middle school student presented statistically significant positive effect to the use of cellular phone dependence of middle school student. We need to provide as basic data for developing cellular phone dependence intervention programs.

Performance Analysis of Cellular IP using Combined Cache and Improved Adaptive Semi-soft Handoff Method (통합 캐시 및 개선된 적응형 세미소프트 핸드오프를 이용한 셀룰러 IP의 성능분석)

  • Choi Jung-Hun;Kim Nam;Jeong Seung-Ho
    • The Journal of the Korea Contents Association
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    • v.4 no.4
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    • pp.113-121
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    • 2004
  • Existing Cellular IP increases the network traffic load, packet loss and handoff latency because of duplicate packet. In this paper, we propose using a Combined Cache that unites a pasing cache with a routing cache and a Improved Adaptive Semi-soft handoff that minimizes to occur the duplicate packet. As a computer simulation, we consider packet loss, handoff latency and traffic load in network. In proportion the number of nodes, mobile hosts and downlinks of node in access network increased, the proposed method is largely improved in comparison with existing Cellular If that uses semi-soft handoff.

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THE IMMUNE SUPPRESSIVE EFFECT FROM THE STRESS OF MAXILLOFACIAL OPERATIONS (구강악안면 영역의 수술이 인체내 세포면역성 억제에 미치는 영향)

  • Kim, Soung-Min;Lee, Suk-Keun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.29 no.2
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    • pp.108-115
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    • 2003
  • Suppression of cellular immunity is the host responses to surgical stress. When the body is exposed to surgical stress, decreased immunocyte function is one of the surgical stress-induced biologic responses. In all patients exposed to the surgical stress, peripheral blood lymphocyte numbers and function were suppressed until at least 2 weeks postoperatively. This immunosuppression was mainly due to a decrease of helper-inducer T cells, cytotoxic T cells, natural killer cells, and an increase of suppressor T cells. The blood levels of interleukin-6(IL-6) cytokine increase in response to surgical stress and cause an increase of so-called acute phase reactants, including C-reactive protein(CRP). In the previously damaged patients group, expected to early stress expose, immunosuppression was more developed than other normal groups. Cellular immunosuppression by surgical stress was mainly due to an increase of lymphocyte subsets that depress cellular immunity coupled with a decrease of the subsets that promote it. Overproduction of CRP in response to surgical stress may play an important role in the development of immunosuppression.

Interference Cancellation and Load Balancing in Heterogeneous Cellular Networks (이기종 셀룰러 네트워크에서 간섭 제거와 로드 밸런싱)

  • Lee, Kyoung-Jae;Jo, Han-Shin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.10
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    • pp.45-49
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    • 2014
  • In this paper, the performance of the interference cancellation using multiple receive antennas is evaluated for heterogeneous cellular systems when user association and load balancing problems are optimized for cell edge users. The simulation results show that the interference cancellation method remarkably improves the rate performance of load-balanced cells.

The effects of ascorbic acid on the morphology and cell proliferation of three-dimensional stem cell spheroids (아스코르브산의 3차원 줄기세포 배양체에 대한 증식 및 분화 효과 분석)

  • Lee, Hyunjin;Yeo, Seong-Il;Park, Jun-Beom
    • The Journal of the Korean dental association
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    • v.55 no.9
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    • pp.592-603
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    • 2017
  • Purpose: The effects of various concentrations of ascorbic acid on stem cell spheroids derived from intraoral areas are not known yet. Thus, the purpose of this study is to evaluate the effects of different concentrations of ascorbic acid on the morphology and cellular viability of stem cell spheroids derived from the gingival tissues. Materials and Methods: Stem cells were plated onto silicon elastomer-based concave microwells and grown in the presence of ascorbic acid at concentrations ranging from 0.003% to 0.3%. The morphology of the cells was viewed under an inverted microscope at day 1, 2, 3 and 5. Qualitative live/dead assay and quantitative cellular viability using Cell Counting Kit-8 were performed on day 2 and day 5. Results: Gingiva-derived stem cells formed spheroids irrespective of ascorbic acid concentration in silicon elastomer-based concave microwells. Increase in the diameter of spheroid were seen with higher concentrations of ascorbic acid. Higher cellular viability was seen in higher concentrations of ascorbic acid. Conclusion: Within the experimental setting, the application of ascorbic acid on stem-cell spheroids produced an increase in the size and higher viability with higher dosage. It can be suggested ascorbic acid be applied with stem cell spheroids for tissue engineering purposes.

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Electron Microscopic Studies on the Cellular Changes in the Liver of Ducklings Induced by Korean Aflatoxin B$_1$ (한국산 Aflatoxin이 오리새끼의 간장에서 유발시킨 병변에 관한 전자현미경적 연구)

  • Lee Kwang-Juing;Yoon Hwa-Juing;Lee In-ho
    • Journal of the korean veterinary medical association
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    • v.26 no.9
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    • pp.543-553
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    • 1990
  • This report describes the cellular changes induced in the livers of ducklings by a sin91e administration of aflatoxin B$_1$ produced by Korean Industrial Strain of the Aspergillus flavus, in order to examine the toxicity of the minimum dose of

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Toxicogenomic Study to Identify Potential New Mechanistic Markers on Direct-Acting Mutagens in Human Hepatocytes (THLE-3)

  • Kim, Youn-Jung;Song, Mi-Kyung;Song, Mee;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • v.3 no.4
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    • pp.231-237
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    • 2007
  • Exposure to DNA-damaging agents can elicit a variety of stress-related responses that may alter the expression of genes associated with numerous biological pathways. We used 19 k whole human genome chip to detect gene expression profiles and potential signature genes in human normal hepatocytes (THLE-3) by treatment of five direct acting mutagens, furylfuramide (AF-2), N-nitroso-N-methylurea (MNU), methylmethanesulfonate (MMS), 4-nitroquinoline-N-oxide (4-NQO) and 2-nitrofluorene (2NF) of the $IC_{20}$ concentration for 3 h. Fifty one up-regulated common genes and 45 down-regulated common genes above 1.5-fold by five direct-acting mutagens were identified by clustering analysis. Many of these changed genes have some association with apoptosis, control of cell cycle, regulation of transcription and signal transduction. Genes related to these functions, as TP73L, E2F5, MST016, SOX5, MAFB, LIF, SII3, TFIIS, EMR1, CYTL1, CX3CR1 and RHOH are up-regulated. Down-regulated genes are ALOX15B, xs155, IFITM1, BATF, VAV2, CD79A, DCDC2, TNFSF8 and KOX8. We suggest that gene expression profiling on mutagens by toxicogenomic analysis affords promising opportunities to reveal potential new mechanistic markers of genotoxicity.