• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.1
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• pp.56-63
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• 2009

Cell migration is one of the essential mechanisms responsible for complex biological processes. Intensive researches have begun to elucidate the mechanisms and search intriguing conditions for efficient control of cell migration. One general mechanism that is widely applicable for cells including Escherichia coli, amoebae and endothelial cell is chemotaxis. The single cell study for bacterial chemotaxis has an advantage over studies with the population of cells in providing a clearer observation of cell migration, which leads to more accurate assessments of chemotaxis. In this paper, we propose a three-dimensional model considering a single bacterium to study its chemotaxis. The semi-implicit Fourier spectral method is applied for high efficiency and numerical stability. The simulation results reveal rich dynamics of cell migration and provide quantitative assessments of bacterial chemotaxis with various chemoattractant gradient fields.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5963-5966
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• 2015

Background: This analysis was conducted to evaluate the efficacy and safety of a combination of gemcitabine and nedaplatin in treating patients with non-small cell lung cancer. Methods: Clinical studies evaluating the efficacy and safety of a combination of gemcitabine and nedaplatin with attention to response and safety for patients with non-small cell lung cancer were identified using a predefined search strategy. Pooled response rates for gemcitabine and nedaplatin were calculated. Results: In gemcitabine and nedaplatin based regimens, 4 clinical studies including 112 patients with non-small cell lung cancer were considered eligible for inclusion. The pooled analysis suggested that the pooled reponse rate was 40.2% (45/112). Main side effects included grade 3-4 neutropenia, thrombocytopenia, and anemia. Grade 3-4 nonhematological toxicity included nausea and vomiting, diarrhea, and hepatic dysfunction. There were no treatment-related deaths. Conclusion: This evidence based analysis suggests that the combination of gemcitabine and nedaplatin is associated with good response rate and accepted toxicity for treating patients with non-small cell lung cancer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3C
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• pp.302-313
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• 2010

In this paper, we propose an enhanced AGC (Automatic Gain Control) structure and P-SCH detection method for initial cell search in 3GPP (3rdGenerationPartnershipProject) LTE (Long Term Evolution) FDD(Frequency Division Duplex) / TDD (Time Division Duplex) dual mode system. Since TDD frame structure consists of uplink subframe and downlink subframe, conventional AGC structure causes P-SCH detection performance degradation by increase of AGC variation due to signal power difference between uplink and downlink subframe. Also, P-SCH detection performance is degraded by distortion of P-SCH correlation characteristic in frequency offset and multipath fading channel environments. Therefore, we propose an AGC structure which can minimize P-SCH detection performance degradation with stable operation in 3GPP LTE TDD mode as well as FDD mode. Also we propose a P-SCH detection method which can reduce distortion of correlation chareteristics in frequency offset and multipath fading environments and obtain good P-SCH detection performance. Simulation results show that the proposed AGC structure and P-SCH detection method have stable AGC operation and excellent P-SCH detection performance for 3GPP LTE TDD / FDD dual mode downlink receiver in various channel environments.

• Journal of Broadcast Engineering
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• v.15 no.3
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• pp.407-413
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• 2010

In DCA (Dynamic Channel Allocation) scheme of uplink cellular system appling a frequency reuse factor of one, when a new call requests a channel, the new call will be blocked if its SINR (Carrier to Noise and Interference Ratio) is less than the required SINR or there is no available channel. The additional channel allocation for the blocked new call can be performed with channel borrowing in the adjacent cells. The channel borrowing causes the CCI (Co-Channel Interference), thus the SINR of the existing calls is deteriorated and the channel reallocation for the existing calls is required. As a result, the channel borrowing leads to a complex calculation so that it is a NP-hard problem. Therefore, to overcome the problem, we propose a novel Group Search-based DCA scheme which decreases the number of the blocked new calls and then reduces the number of the channel reallocation by the channel borrowing for the blocked new calls. The proposed scheme searches the all channels in a group of the adjacent cells and home cell at the same time in order to minimizes the number of the blocked new calls. The simulation results show that proposed Group Search-based DCA scheme provides better new call blocking probability and system throughput than the existing Single Search-based DCA scheme which searches only the channels in home cell.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.315-320
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• 2015

Proposal algorithm in this paper introduced cells, units of router group, for distributed processing of previous genetic algorithm. This paper presented ways to reduce search delay time of overall network through cell-based genetic algorithm. As a result of performance analysis comparing with existing genetic algorithm through experiments, the proposal algorithm was verified superior in terms of costs and delay time. Furthermore, time for routing an alternative path was reduced in proposal algorithm, in case that a network was damaged in existing optimal path algorithm, Dijkstra algorithm, and the proposal algorithm was designed to route an alternative path faster than Dijkstra algorithm, as it has a 2nd shortest path in cells of the damaged network. The study showed that the proposal algorithm can support routing of alternative path, if Dijkstra algorithm is damaged in a network.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.62-62
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• 2007

It is analyzed with regard to LCD in Korea that national patent application, applicant patent application, IPC patent application. The Trends of patent application concentrated LCD manufacturing process and device, case and a cell of liquid crystal. Therefore, the future research and developments must be centralized these ranges. It is needed for competitive power and original technology that the search and analysis of the previous patent.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.521-527
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• 2020

Quantum-dot cellular automata (QCA) is a technology that attracts attention as a next-generation digital circuit design technology, and several digital circuits have been proposed in the QCA environment. Content-addressable memory (CAM) is a storage device that conducts a search based on information stored therein and provides fast speed in a special process such as network switching. Existing CAM cell circuits proposed in the QCA environment have a disadvantage in that a required area and energy dissipation are large. The CAM cell is composed of a memory unit that stores information and a match unit that determines whether or not the search is successful, and this study proposes an improved QCA CAM cell by designing the memory unit in a multi-layer structure. The proposed circuit uses simulation to verify the operation and compares and analyzes with the existing circuit.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.105-110
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• 1999

In our continuing search for new antineoplastic agents from natural products, one hundred and thirty-five herbal drugs were extracted with petroleum ether/ether (1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3(human ovary adenocarcinoma) cell lines. Among them, fifteen kinds of ether extracts, eighteen kinds of ethyl acetate extracts and seven kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml,$ while ten kinds of ether extracts, thirteen kinds of ethyl acetate extracts and six kinds of methanol extracts demonstrated significant cytotoxic activities against SK-OV-3 cell lines at the above same concentration.

• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.323-330
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• 1998

For the search of new antineoplastic agents from natural resources, two hudred and one kinds of oriental medicinal drugs were extracted with petroleum ether/ether(1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3 (human ovary adenocarcinoma) cell lines. Among them, thirty kinds of ether extracts, forty-one kinds of ethyl acetate extracts and nine kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml$. And also, twenty-four kinds of ether extracts, thirty-one kinds of ethyl acetate extracts and six kinds of methanol extracts showed significant cytotoxic activities against SK-OV-3 cell lines at the same concentration.

• Korean Journal of Pharmacognosy
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• v.34 no.1 s.132
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• pp.28-32
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• 2003

In order to search for the anti-HIV agents from natural products, eighty MeOH extracts of medicinal plants were applied to a syncytia formation inhibition assay which is based on the interaction between the HIV-1 envelope glycoprotein gp120/gp41 and the cellular membrane protein CD4 of T lymphocytes. Among them, Ailanthus altissima showed a potent virus-cell fusion inhibitory activity. Repeated column chromatoghaphy of the methylene chloride fraction of A. altissima afforded compounds 1$({\beta}-sitosterol-3-O-{\beta}-D-glucoside)$, 2(tetramethoxycoumarin), and 3(ocotillone). Virus-cell fusion inhibitory activity of compound 3(ocotillone) was $70.76{\pm}4.09%$ at the concentration of $100\;{\mu}g/ml$.