• 제목/요약/키워드: Cell selection

검색결과 723건 처리시간 0.024초

자율이동로봇군의 협조전략과 군행동의 실현을 위한 면역시스템의 모델링 (An Immune System Modeling for Realization of Cooperative Strategies and Group Behavior in Collective Autonomous Mobile Robots)

  • 이동욱;심귀보
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 춘계학술대회 학술발표 논문집
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    • pp.127-130
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    • 1998
  • In this paper, we propose a method of cooperative control(T-cell modeling) and selection of group behavior strategy(B-cell modeling) based on immune system in distributed autonomous robotic system(DARS). Immune system is living body's self-protection and self-maintenance system. Thus these features can be applied to decision making of optimal swarm behavior in dynamically changing environment. For the purpose of applying immune system to DARS, a robot is regarded as a B cell, each environmental condition as an antigen, a behavior strategy as an antibody and control parameter as a T-call respectively. The executing process of proposed method is as follows. When the environmental condition changes, a robot selects an appropriate behavior strategy. And its behavior strategy is stimulated and suppressed by other robot using communication. Finally much stimulated strategy is adopted as a swarm behavior strategy. This control scheme is based of clonal selection and idiotopic network hypothesis. And it is used for decision making of optimal swarm strategy. By T-cell modeling, adaptation ability of robot is enhanced in dynamic environments.

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Process Development of therapeutic antibody (ISU301) using disposable bioreactor

  • Park, Heung-Rok
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVI)
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    • pp.39-39
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    • 2005
  • Large scale mammalian cell culture has become, over the past two decades, the preferred method to produce therapeutic monoclonal antibodies. In this presentation, I will introduce disposable bioreactor system and analyze key factors and points for consideration during mammalian cell culture process development. Example will be provided highlighting the selection of master cell, culture media and environmental factors based on productivity and product quality.

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Research on Per-cell Codebook based Channel Quantization for CoMP Transmission

  • Hu, Zhirui;Feng, Chunyan;Zhang, Tiankui;Gao, Qiubin;Sun, Shaohui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권6호
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    • pp.1828-1847
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    • 2014
  • Coordinated multi-point (CoMP) transmission has been regarded as a potential technology for LTE-Advanced. In frequency division duplexing systems, channel quantization is applied for reporting channel state information (CSI). Considering the dynamic number of cooperation base stations (BSs), asymmetry feature of CoMP channels and high searching complexity, simply increasing the size of the codebook used in traditional multiple antenna systems to quantize the global CSI of CoMP systems directly is infeasible. Per-cell codebook based channel quantization to quantize local CSI for each BS separately is an effective method. In this paper, the theoretical upper bounds of system throughput are derived for two codeword selection schemes, independent codeword selection (ICS) and joint codeword selection (JCS), respectively. The feedback overhead and selection complexity of these two schemes are analyzed. In the simulation, the system throughput of ICS and JCS is compared. Both analysis and simulation results show that JCS has a better tradeoff between system throughput and feedback overhead. The ICS has obvious advantage in complexity, but it needs additional phase information (PI) feedback for obtaining the approximate system throughput with JCS. Under the same number of feedback bits constraint, allocating the number of bits for channel direction information (CDI) and PI quantization can increase the system throughput, but ICS is still inferior to JCS. Based on theoretical analysis and simulation results, some recommendations are given with regard to the application of each scheme respectively.

다중 사용자 MIMO 채널 환경에서 셀 용량을 증가시키는 사용자 선택 기법 (An User Selection Scheme Enhancing Cell Capacity for Multi-user MIMO Channel Environment)

  • 정재호;최승원
    • 한국통신학회논문지
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    • 제36권1C호
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    • pp.22-27
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    • 2011
  • 본 논문에서는 하향링크 다중 사용자 Multiple Input Multiple Output (MIMO)채널 환경에서 셀 용량을 증가시키기 위한 Zero Forcing 기반의 효율적 사용자 선택 기법을 제안한다. 이 기법에서는 채널 전력이 미리 결정된 한계점을 초과하는 사용자들을 주요 그룹으로 구성한다. 100명의 사용자와 4개의 기지국 안테나를 가정한 컴퓨터 모의실험을 통해서 제안된 기법이 기존 기법보다 0.33 bps/Hz 만큼 젤 용량을 추가로 제공할 수 있음이 밝혀졌다.

반수체 담배의 엽육 원형질체로부터 MNNG 처리에 의한 Glyphosate 저항성 클론의 선별 (Selection of Glyphosate-Resistant Clones form MNNG-treated Mesophyll Protoplasts of Haploid Tobacco Plants)

  • 성순기
    • Journal of Plant Biology
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    • 제36권1호
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    • pp.105-112
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    • 1993
  • Selection of glyphosate-resistant clones from MNNG-treated mesophyll protoplasts of haploid tobacco and their differentiation were studied. The protoplasts were treated with 0.1 to 100 $\mu\textrm{g}$/mL N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) for 30 min when they expanded to oval shapes. After the treatment, the protoplasts in 4-16 cell stages were transferred to the selective medium containing 1 mM glyphosate for the selection of the glyphosate-resistant colonies. The efficiency of the cell division of the protoplasts in the selective medium decreased as the MNNG concentrations in creased. Optimal MNNG concentration for induction of the glyphosate-resistant clones was 10$\mu\textrm{g}$/mL and mutation frequency was 2.66$\times$10-6. The stability of the glypohsate-resistance of the clones was examined by prolonged subculture in the medium with 1 mM glyphosate, and the resistant clones were survived more than 10 months. Among them one clone has been proliferating and greening and the others were proliferating without greening or greening with slower proliferating.

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Individual Charge Equalization Converter Using Selective Two Current Paths for Series Connected Li-ion Battery Strings

  • Kim, Chol-Ho;Park, Hong-Sun;Moon, Gun-Woo
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2008년도 하계학술대회 논문집
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    • pp.274-276
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    • 2008
  • This paper proposes an individual charge equalization converter using selective two current paths for series connected lithium-ion battery strings. In the proposed equalizer, a central equalization converter acting as a controllable current source is sequentially connected in parallel with individual batteries through an array of cell selection switches. A flyback converter with a modified rectifier realizes a controllable current source. A central equalization converter is shared by every battery cells through the cell selection switch, instead of a dedicated charge equalizer for each cell. With this configuration, although the proposed equalizer has one dc-dc converter, individual charge equalization can be effectively achieved for the each cell in the strings. Furthermore, since the proposed equalizer would not allocate the separated dc-dc converter to each cell, such that the implementation of great size reduction and low cost can be allowed. In this paper, an optimal power rating design guide is also employed to obtain a minimal balancing size while satisfying equalization requirements. A prototype for eight lithium-ion battery cells is optimally designed and implemented. Experimental results verify that the proposed equalization method has good cell balancing performance showing small size, and low cost.

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Fine Mapping of the Rice Bph1 Gene, which Confers Resistance to the Brown Planthopper (Nilaparvata lugens Stal), and Development of STS Markers for Marker-assisted Selection

  • Cha, Young-Soon;Ji, Hyeonso;Yun, Doh-Won;Ahn, Byoung-Ohg;Lee, Myung Chul;Suh, Seok-Cheol;Lee, Chun Seok;Ahn, Eok Keun;Jeon, Yong-Hee;Jin, Il-Doo;Sohn, Jae-Keun;Koh, Hee-Jong;Eun, Moo-Young
    • Molecules and Cells
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    • 제26권2호
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    • pp.146-151
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    • 2008
  • The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452.

유세포 분석기를 이용한 galectin-3에 의해 유도된 흉선세포의 apoptosis 분석 (Flow cytometric analysis of apoptosis in mouse thymocytes by galectin-3)

  • 김태중;우희종
    • 대한수의학회지
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    • 제39권6호
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    • pp.1112-1118
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    • 1999
  • Galectin-3 plays an important role in cell development, differentiation and cancer metastasis, including cell-cell/extracellular matrix (ECM) interactions and is supposed to have an effect of apoptosis on T-cells in thymic clonal selection. In this study, to know the effect of galectin-3 on thymocyte development, we used recombinant human galectin-3 (rHgal-3) from Escherichia coli, JM105, which was inserted with human gal-3 gene-transformed plasmid vector (prGal-3) to express human galectin-3. Expressed rHgal-3 was confirmed by western blot using the culture supernant of hybridoma (M3/38) producing monoclonal antibody to human galectin-3. Sepharose gel affinity chromatography was used to purify the expressed rHgal-3. Thymocytes and hepatocytes from 6-week-old male BALB/c mice were incubated with rHgal-3 and showed marked increase of apoptotic population on analysis using flow cytometry with 7-AAD in a dosedependent manner. However, rHgal-3 failed to induce apoptosis on hepatocytes. Interestingly, this apoptotic effect was not inhibited by lactose, a specific lectin domain inhibitor. From these results, we concluded that extrinsic -3 induces apoptosis on mouse thymocytes, and galectin-3 may have an apoptotic effect on T-cells in thymic clonal selection.

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Microfluidic Devices for Cell Analysis

  • Bachman, Mark;Li, G.P.
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2009년도 추계학술발표대회
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    • pp.3.2-3.2
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    • 2009
  • Microfluidics and BioMEMStechnology has increasingly been used as a tool for studying small volumes oftissue and even individual cells. One of the most important benefits ofmicrofluidic technology is the potential to build devices that analyze and sortmammalian cells. The "sorting problem" typically requires that a fewcells be selected and isolated from a larger population of hundreds, thousandsor even millions of other cells. For example, cancer tumor cells may resideamong a large population of healthy cells, but it would be of great interest toidentify, isolate and study only the cancer cells. In another application, onemay want to determine the number of white blood cells within a sample of blood.We have developed microfluidic devices that enable researchers to select cellsfrom a population by a variety of methods, including antibody staining,dielectrophoretic selection, and physical size selection. These devices haveapplications in cancer research where cancer cells must be identified fromnormal tissue, but where only small samples of tissue are available. In thistalk, we will present some of our microfluidic cell sorting devices, discusstheir physical principles, and their use in biological applications.

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A Modularized Two-Stage Charge Equalization Converter for Series Connected Lithium-Ion Battery Strings

  • Kim, Chol-Ho;Park, Hong-Sun;Moon, Gun-Woo
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2008년도 하계학술대회 논문집
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    • pp.535-537
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    • 2008
  • This paper proposes a modularized two-stage charge equalization converter for a series-connected lithium-ion battery string. In this paper, the series-connected battery sting is modularized into M modules, and each module has K cells in series. With this modularization, low voltage stress on the electronic devices can be achieved. A two-stage dc-dc converter with cell selection switches is employed. The first stage dc-dc converter steps down the high bus voltage to about 10 V. The second stage dc-dc converter integrated with selection switches equalizes the cell voltages. A prototype for 88 lithium-ion battery cells is optimally designed and implemented. Experimental results verify that the proposed equalization method has good cell balancing performance showing low voltage stress, small size, and low cost.

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