• Title/Summary/Keyword: Genetic stability

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Design of GA-Fuzzy Precompensator of TCSC-PSS for Enhancement of Power System Stability (전력계통 안정도 향상을 위한 TCSC 안정화 장치의 GA-퍼지 전 보상기 설계)

  • Chung Mun Kyu;Wang Yong Peel;Chung Hyeng Hwan;Lee Chang Woo;Lee Jeong Phil;Hur Dong Ryol
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.292-294
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    • 2004
  • In this paper, we design the GA-fuzzy precompensator of a Power System Stabilizer for Thyristor Controlled Series Capacitor(TCSC-PSS) for enhancement of power system stability. Here a fuzzy precompensator is designed as a fuzzy logic-based precompensation approach for TCSC-PSS. This scheme is easily implemented simply by adding a fuzzy precompensator to an existing TCSC-PSS. And we optimize the fuzzy precompensator with a genetic algorithm for complements the demerit such as the difficulty of the component selection of fuzzy controller, namely, scaling factor, membership Auction and control rules. Simulation results show that the proposed control technique is superior to a conventional PSS in dynamic responses over the wide range of operating conditions and is convinced robustness and reliableness in view of structure.

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Agrobactrium tumefaciens-Mediated Transformation of Monascus ruber

  • Yang, Yun-Jung;Lee, In-Hyung
    • Journal of Microbiology and Biotechnology
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    • v.18 no.4
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    • pp.754-758
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    • 2008
  • Agrobacterium tumefaciens-mediated transformation (ATMT) was successfully applied to Monascus ruber. The optimum cocultivation time was 84 h with an efficiency of 900 to 1,000 transformants when $1{\times}10^6$ spores were used with the same volume of bacteria. The stability of transform ants was over 98% after five generations. When M. ruber was transformed with A. tumefaciens YL-63 containing the green fluorescent protein gene (egfp), the green fluorescent signal was observed throughout hyphae, confirming expression of the gene. This efficient transformation and expression system of M. ruber by ATMT will facilitate the study of this fungus at a molecular genetic level.

Optimum Allocation of Reactive Power in Real-Time Operation under Deregulated Electricity Market

  • Rajabzadeh, Mahdi;Golkar, Masoud A.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.3
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    • pp.337-345
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    • 2009
  • Deregulation in power industry has made the reactive power ancillary service management a critical task to power system operators from both technical and economic perspectives. Reactive power management in power systems is a complex combinatorial optimization problem involving nonlinear functions with multiple local minima and nonlinear constraints. This paper proposes a practical market-based reactive power ancillary service management scheme to tackle the challenge. In this paper a new model for voltage security and reactive power management is presented. The proposed model minimizes reactive support cost as an economic aspect and insures the voltage security as a technical constraint. For modeling validation study, two optimization algorithm, a genetic algorithm (GA) and particle swarm optimization (PSO) method are used to solve the problem of optimum allocation of reactive power in power systems under open market environment and the results are compared. As a case study, the IEEE-30 bus power system is used. Results show that the algorithm is well competent for optimal allocation of reactive power under practical constraints and price based conditions.

Study on Productivity and Genotype Structure by Several Enzyme Loci of Silkworm(Bombyx mori L.) Parthenoclones Obtained by Thermal and Combined(Low-High Temperature) Method

  • Vasileva, Jolanda Bogdanova;Staykova, Teodora Atanasova;Tzenov, Panomir Ivanov
    • International Journal of Industrial Entomology and Biomaterials
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    • v.18 no.2
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    • pp.131-134
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    • 2009
  • The purpose of this study was to establish whether there are differences in the productivity of the same silkworm(Bombyx mori L.) parthenoclones, obtained by two different methods-thermal and combined, as well as to study their genotype structure by several enzyme loci. It was established that all individuals of parthenoclones Joana, Joana(${\downarrow}{\uparrow}$), Pohi and Pohi(${\downarrow}{\uparrow}$), are homozygous by the studied esterase and phosphoglucomutase loci, which substantiated the clones' genetic stability. By comparative analysis of some biological and technological properties, it was found that parthenoclone Pohi(${\downarrow}{\uparrow}$) obtained by low-high temperature activation is characterized by higher values of these properties as compared to parthenoclone Pohi obtained by thermal parthenogenesis. Comparing the two methods of inducing ameiotic parthenogenetic development, we would recommend that parthenoclone Joana is sustained by thermal parthenogenesis, and parthenoclone Pohi-by the combined method (low-high temperature).

An Optimal Parameter Selection of Power System Stabilizer using Immune Algorithm (면역 알고리즘을 이용한 전력 계통 안정화 장치의 최적 파라미터 선정)

  • Jeong, Hyeong-Hwan;Lee, Jeong-Pil;Jeong, Mun-Gyu;Lee, Gwang-U
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.49 no.9
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    • pp.433-445
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    • 2000
  • In this paper, optimal tuning problem of power system stabilizer(PSS) using Immune Algorithm(IA) is investigated to improve power system dynamic stability. In proposed method, objective function is represented as antigens. An affinity calculation is embedded within the algorithm for determining the promotion or suppression of antibody. An antibody that most fits the antigen is considered as the solution to PSS tuning problem. The computaton performance by the proposed method is compared with Genetic Algorithm(GA). The porposed PSS using IA has been applied for two sample system, single-machine infinite bus system and multi-machine power system. The performance of the proposed PSS is compared with that of conventional PSS. It is shown that the proposed PSS tuned using immune algorithm is more robust than conventional PSS.

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Modified SOD for Cosmeceuticals

  • Kang, Nae-Gyu;Lim, Jun-Man;Chang, Min-Youl;Park, Sun-Gyoo;Cho, Wan-Goo;Kang, She-Hoon;Park, Soo-Young
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.630-644
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    • 2003
  • A human Cu, Zn-superoxide dismutase (Cu, Zn-SOD) was fused with a Tat PTD of HIV-1 to produce a novel anti-aging ingredient, Tat-SOD for cosmeceuticals. Test of stability and evaluation of transduction efficacy and enzymatic activity suggest Tat-SOD is an effective active ingredient for anti-aging treatment.

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Activation-induced Cytidine Deaminase in B Cell Immunity and Cancers

  • Park, Seok-Rae
    • IMMUNE NETWORK
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    • v.12 no.6
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    • pp.230-239
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    • 2012
  • Activation-induced cytidine deaminase (AID) is an enzyme that is predominantly expressed in germinal center B cells and plays a pivotal role in immunoglobulin class switch recombination and somatic hypermutation for antibody (Ab) maturation. These two genetic processes endow Abs with protective functions against a multitude of antigens (pathogens) during humoral immune responses. In B cells, AID expression is regulated at the level of either transcriptional activation on AID gene loci or post-transcriptional suppression of AID mRNA. Furthermore, AID stabilization and targeting are determined by post-translational modifications and interactions with other cellular/nuclear factors. On the other hand, aberrant expression of AID causes B cell leukemias and lymphomas, including Burkitt's lymphoma caused by c-myc/IgH translocation. AID is also ectopically expressed in T cells and non-immune cells, and triggers point mutations in relevant DNA loci, resulting in tumorigenesis. Here, I review the recent literatures on the function of AID, regulation of AID expression, stability and targeting in B cells, and AID-related tumor formation.

New Insights into the Protein Turnover Regulation in Ethylene Biosynthesis

  • Yoon, Gyeong Mee
    • Molecules and Cells
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    • v.38 no.7
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    • pp.597-603
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    • 2015
  • Biosynthesis of the phytohormone ethylene is under tight regulation to satisfy the need for appropriate levels of ethylene in plants in response to exogenous and endogenous stimuli. The enzyme 1-aminocyclopropane-1-carboxylic acid synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis, plays a central role to regulate ethylene production through changes in ACS gene expression levels and the activity of the enzyme. Together with molecular genetic studies suggesting the roles of post-translational modification of the ACS, newly emerging evidence strongly suggests that the regulation of ACS protein stability is an alternative mechanism that controls ethylene production, in addition to the transcriptional regulation of ACS genes. In this review, recent new insight into the regulation of ACS protein turnover is highlighted, with a special focus on the roles of phosphorylation, ubiquitination, and novel components that regulate the turnover of ACS proteins. The prospect of cross-talk between ethylene biosynthesis and other signaling pathways to control turnover of the ACS protein is also considered.

A Design on Optimal Satellite-Tracking Antenna Control system Using GA (GA를 이용한 최적 위성추적 안테나 제어 시스템의 설계)

  • Jeong, H.S.;Kim, D.W.;Hwang, H.J.;Kim, J.T.;Kim, G.Y.;Kim, Y.H.;Cho, W.R.
    • Proceedings of the KIEE Conference
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    • 1998.07b
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    • pp.549-551
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    • 1998
  • In this paper, we design the optimal satellite-tracking antenna $H_{\infty}$ control system using genetic algorithm(GA). To do this, we give gain and dynamics parameters to the weighting functions and apply GA with reference model to the optimal determination of weighting functions and design parameter ${\gamma}$ that are given by Glover-Doyle algorithm which can design $H_{\infty}$ controller in the state space. These weighting functions and design parameter ${\gamma}$ are simultaneously optimized in tile search domain guaranteeing the robust stability of closed-loop system. The effectiveness of this satellite-tracking antenna $H_{\infty}$ control system is verified by computer simulation.

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Energy Optimization for The Walking of Biped Robot (이족보행로봇의 보행을 위한 에너지 최적화)

  • Kim, Jong-Tae;Choi, Sang-Ho;Lim, Sun-Ho;Kim, Jin-Geol
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2339-2341
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    • 1998
  • This paper is concerned with an energy optimization for the walking of IWR biped robot. The movement of balancing joints are determined by ZMP(Zero Moment Point) and dynamic properties caused by motion of a swing leg. Therefore, ZMP positions have an important role in walking and guarnateeing the stability of a robot. A genetic algorithm is utilized for solving this problem and finding ZMP with a minimum energy at each sampling time during the walk. In this study, we performed an energy optimization with desired ZMP trajectories and motion of balancing joints.

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