• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.3
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• pp.106-112
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• 2004

This paper presents a new heuristic algorithm for the machine cell(MC) formation problem. MC formation problem is represented as an unbalanced k-way network partition and the proposed algorithm uses four stage-approach to solve the problem. Four stages are natural sub-network formation, determination of intial vertexes for each sub-network, determination of initial partition, and improvement of initial partition. Results of experiments show that the suggested algorithm provides near optimal solutions within very short computational time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8B
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• pp.687-694
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• 2012

In OFDMA-based cellular system, inter-cell interference (ICI) reduces system capacity by aggravating receiving performance of the users located in edge of the cell. Therefore, to mitigate ICI is very important issue in cellular system. To deal with ICI problem, fractional frequency reuse (FFR) is introduced. FFR is an interference management technique. It separates each cell into inner cell and outer cell. Then, it allocates whole system bandwidth to inner cell and different frequency partition to each sector of outer cell. By doing this, outer cell users can ignore interferences from adjacent cells. So, the receiving performance of the cell edge users can be fairly increased. However, using FFR technique has a fatal side effect. In order to use different frequency partition among three sectors of outer cell, they can use only a third of the whole system bandwidth. Then, the reduction of available bandwidth reduces the system throughput directly. To solve this problem, we propose a new FFR method that allocates partially overlapped frequency partition to each sector of outer cell. And then, we suggest a proper overlapping ratio for practical cellular system.

• Journal of Nutrition and Health
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• v.35 no.8
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• pp.880-885
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• 2002

This study was performed to determine the antimicrobial and anticarcinogenic activities of the Momordica charantia L. (MC) on several microorganisms and human cancer cell lines. In the paper disk test, its antimicrobial activity was increased in proportion to its concentration. Among the various solvent fractions of Momordica charantia L., the ethylether partition layer (MCMEE) showed the strongest antimicrobial activity. Also, the ethylacetate partition layer (MCMEA) and the butanol partition layer (MCMB) showed antimicrobial activity. We also determined the cytotoxicity and chemopreventive effect of Momordica charantia L. extract and fractions on human cancer cells. The experiment was conducted to determine the cytotoxicity of Momordica charantia L. partition layers on HepG2, HeLa and MCF-7 cells by MTT assay. Among the various partition layers of Momordica charantia L., MCMEE and MCMEA showed strong cytotoxic effects on all cancer cell lines. The chemopreventive effect of the quinone reductase induced activities of HepG2 cell, the hexane partition layer (MCMH) at a dose of 50 $\mu\textrm{g}$/mL was 3.62 times more effective compared with the control values of 1.0. Therefore, based on these studies, Momordica charantia L. may be developed into a potentially useful cancer chemopreventive agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.143-148
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• 2002

We investigated the cytotoxicity effects of Lycii fructus (LF) on HePG2, MCF7 and C6 cell lines by the MTT assay. We extracted the methanol (LFM) and fractionated to five partition layers. Among partition layers, the ethylether partition layer (LFMEE) was showed the strongest cytotoxic effects on all cancer cell lines. The hexane partition layer (LFMH) also was showed significant cytotoxic activities on Hela and MCF-7 cell lines. We also determined the induction of intracellular quinone reductase (QR) activity on HepG2 cells. Among various partition layers of Lycii fructus; LFMH was showed the most effective such induced effect such as 1.85 to the control value of 1.0. And we also determined the enhancement of anticarcinogenic effect by combination of Lycii fructus with vitamin C on all cell lines. These results suggest that potentially useful anticarcinegenic chemicals could be isolated from LFMEE and LFMH of the Lycii frutus and also we found the enhanced effect by the combination of various partition layers of LFM with vitamin C.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.2
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• pp.59-71
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• 2004

Melanin pigmentation has an essential role in protecting human skin against the damaging effects of ultra violet radiation, infection, environmental factor, etc. However abnormal melanin pigmentation can directly cause a number of congenital and acquired pigmentary skin disease. This study conducted to evaluate the effects of various partition extracts of Codonopsis lanceolata on the melanogenesis in the B 16 melanoma cells. The cells were treated for 3 days with various partition extracts of Codonopsis lanceolata. While treatment with the BuOH partition extract of Codonopsis lanceolata increased significantly the tyrosinase activity and melanin content, the n-Hexane or ethyl acetate partition extract dose-dependently suppressed them compared with untreated control. But ethyl acetate partition significantly decreased the cell viability. The H2O partiton extract at various concentrations did not exhibit any significant change on the melanogenesis. These results indicate that treatment with the n-Hexane partition extract inhibits the melanogenesis in B16 melanoma cells, and raise the possibility that this extract may be effective in the abnormal melanin pigmentation as well as the whitening agent for the skin.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.4703-4723
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• 2018

In recent years, dense small cell network has been deployed to address the challenge that has resulted from the unprecendented growth of mobile data traffic and users. It has proven to be a cost efficeient solution to offload traffic from macro-cells. Software defined heterogeneous wireless network can decouple the control plane from the data plane. The control signal goes through the macro-cell while the data traffic can be offloaded by small cells. In this paper, we propose a framework for cell virtualization and user association in order to satisfy versatile requirements of multiple tenants. In the proposed framework, we propose an interference graph partioning based virtual-cell association and customized physical-cell association for multi-homed users in a software defined small cell network. The proposed user association scheme includes 3 steps: initialization, virtual-cell association and physical-cell association. Simulation results show that the proposed virtual-cell association outperforms the other schemes. For physical-cell association, the results on resource utilization and user fairness are examined for mobile users and infrastructure providers.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.134-142
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• 2007

This study was performed to determine the antioxidative and cytotoxic effects of Elaeagnus multiflora by examining its scavenging effects on the 1,1-diphenyl-2-picryl-hydrazyl(DPPH) radical, the inhibition of lipid peroxidation, and its inhibitory effects on cancer cell proliferation in HeLa cells, MCF-7 cells, and SNU-638 cells by MTT assay. Here, dried samples were extracted in ehtanol at room temperature and fractionated into five different solvent types: hexane, dichloromethane, ethylacetate, butanol, and aqueous partition layers. The hexane(62.92${\pm}$2.45%) and dichloromethane(65.25${\pm}$4.74%) fractions of Elaeagnus multiflora's flesh, and the aqueous(94.65${\pm}$0.02%) and ethylacetate(93.83${\pm}$0.02%) fractions of Elaeagnus multiflora's seeds, inhibited DPPH radical production. The DPPH radical scavenging effects of the flesh and seed were different according to solvent fractions. The inhibition of lipid peroxidation by the flesh and seed extracts were 76.11${\pm}$3.66 and 69.57${\pm}$2.27, respectively, for hexane and 67.57${\pm}$2.43 and 62.09${\pm}$0.90, respectively, for the dichloromethane fraction. Among the various partition layers of Elaeagnus multiflora's flesh, hexane and dichloromethane showed the strong cytotoxicities on all the cancer cell lines used in the study. Also all the fractions of Elaeagnus multiflora's seed exhibited significant effects on the inhibition of cancer cell growth(hexane > dichloromethane > ethylacetate > butanol > aqueous partition layers). These results indicate that the haxane and dichloromethane partition layers of Elaeagnus multiflora's flesh and seed extracts have possible antioxidative and anticancer capacities. Although further studies are needed, the present work suggests that Elaeagnus multiflora may be an antioxidative and chemopreventive agent.

• KSBB Journal
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• v.5 no.2
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• pp.95-100
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• 1990

Ethanol fermentations of inulin by K.fraglis in aqueous two-phase system of PEG/Dextran were performed not only to investigate the characteristics of partition of ethanol, sugar, and cell in the upper phase and the bottom phase but also to compare the fermentation properties with those of single phase system. In the range of 1 to 3 wt% of Dextran, ethanol fermentability and ethanol productivity reduced according to the increase of the molecular weight of PEG. But the cell yield and the cell productivity showed the opposite trend. In the region of 6 to 10 wt% of PEG, the increase of the concentration of PEG, caused the minute decrease of ethanol productivity but the remarkable augmentation of cell productivity. According to the increase of the molecular weight of PEG, the partition coefficient of inulin slightly decreased. But with the increment of the concentration of Dextran, the partition coefficient and the partition yield of inulin in the bottom Phase represented the trends of increase.

• Journal of Nutrition and Health
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• v.40 no.6
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• pp.493-499
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• 2007

Celastrus orbiculatus (CO) has been used as a traditional herb medicine to treat fever, chill, joint pain, edema, rheumatoid arthritis and bacterial infection in China and Korea. In this study, we investigated anticarcinogenic effects of Celastrus orbiculatus (CO). CO was extracted with methanol (COM), and then further fractionated into four different types: methanol (COMM), hexane (COMH), butanol (COMB) and aqueous (COMA) partition layers. We determined the cytotoxicity of these four partitions in four kind of cancer cell lines, such as HepG2, MCF-7, HT29 and B16F10 Cells by MTT assay. Among various partition layers of CO, the COMM showed the strongest cytotoxic effects on cancer cell lines we used. We also observed quinone reductase (QR) induced effects in all partition layers of CO on HepG2 cells. The QR induced effects of COMM on HepG2 cells at 80 ${\mu}$ g/mL concentration indicated 3.28 to a control value of 1.0. The COMM showed the highest induction activity of quinone reductase on HepG2 cells among the other partition layers. Although further studies are needed, the present work suggests that CO may be a chemopreventive agent for the treatment of human cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.136-142
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• 2002

Anticarcinogen is one of the major strategies for cancer control. It is well established that dietary factors play an important role in modulating the development of certain types of human cancer. We investiagted the anticarcinogenic effects of Sedum sarmentosum Bunge (SS) with Platycodon grandiflorum A. extracts on HepG2, HeLa and MCF-7 cell lines. By the MTT assay, among the five partition layers of methanol extract of SS (SSM), the ethylether partition layer of SS (SSMEE) showed the strongest cytotoxic effects on all cell lines. We also investigated the synergistic effect of the combination of SS and PG extracts on growth inhibition of the HepG2, HeLa and MCF-7 cell lines compared to the effects of five partition layers of SSM. Combination of SS and PG extracts significantly increased cytotoxic effects on all cell lines. Therefore, we were able to conclude that ethylether partition layer, SSMEE might have potentially useful cytotoxic materials on all the human cancer cells which we used. And we could suggest that the combination of SS with PG enhanced the anticarcinogenic effect on HepG2, HeLa and MCF-7 cell lines. We also determined QR activity of partition layers of SSM, among them, SSMEE on HepG2 cells showed the highest QR activity, 3.21 as control value of 1.0.