• Korean Journal of Microbiology
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• v.52 no.1
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• pp.120-124
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• 2016

A certain size of DNA (28-29 kb long) to be packaged into P2-size head and the mutation in sid gene of bacteriophage P4 are the major factors to overcome "P2 sir-associated helper inefficiency". To clarify whether the presence of sid mutation is essential to overcome "P2 sir-associated helper inefficiency" or not, we tested the P4 derivative, P4 delRI::kmr, which is $sid^+$ and whose genome size supposed to be 28.5 kb long in the case of being packaged into $P2_{sir3}$-sized large head. As P4 delRI::kmr showed the low EOP with P2 sir3 lysogen, P4 delRI::kmr phage stock was prepared in P2 sir3 lysogen host to increase the EOP with P2 sir3 lysogen. Through this process, P4 delRI::kmr had been adapted for P2 sir3 lysogen. With a CsCl buoyant equilibrium density gradient experiment and gel electrophoresis of the isolated DNA, it was evident that the adaptation of P4 delRI::kmr for P2 sir3 lysogen was caused by the conformational change of DNA to be packaged into large head. The burst size determination experiments with P4 delRI::kmr phage stock adapted for P2 sir3 lysogen and normal P4 delRI::kmr phage stock showed that not the sid mutation but the size of DNA to be packaged (28-29 kb long) was essential to overcome "P2 sir-associated helper inefficiency".

• Molecules and Cells
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• v.28 no.4
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• pp.389-395
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• 2009

We previously observed that the transcription of some flagellar genes decreased in Salmonella Typhimurium tdcA mutant, which is a gene encoding the transcriptional activator of the tdc operon. Since flagella-mediated bacterial motility accelerates the invasion of Salmonella, we have examined the effect of tdcA mutation on the invasive ability as well as the flagellar biosynthesis in S. Typhimurium. A tdcA mutation caused defects in motility and formation of flagellin protein, FliC in S. Typhimurium. Invasion assays in the presence of a centrifugal force confirmed that the defect of flagellum synthesis decreases the ability of Salmonella to invade into cultured epithelial cells. In addition, we also found that the expression of Salmonella pathogenicity island 1 (SPI1) genes required for Salmonella invasion was down-regulated in the tdcA mutant because of the decreased expression of fliZ, a positive regulator of SPI1 transcriptional activator, hilA. Finally, the virulence of a S. Typhimurium tdcA mutant was attenuated compared to a wild type when administered orally. This study implies the role of tdcA in the invasion process of S. Typhimurium.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.607-612
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• 1998

In this paper, a controller using fuzzy-genetic algorithms is proposed for pat-tracking of WMR. A fuzzy controller is implemented so as to adjust appropriate crossover rate and mutation rate. A genetic algorithms is also implemented to have adaptive adjustment of control gain during optimizing process. To check effectiveness of this algorithms, computer simulation is applied.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.140-140
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• 2000

Traditional genetic algorithms, though robust, are generally not the most successful optimization algorithm on any particular domain. Hybridizing a genetic algorithm with other algorithms can produce better performance than both the genetic algorithm and the other algorithms. In this paper, we use random process and simulated annealing instead of mutation operator in order to get well tuned fuzzy rules. The key of this approach is to adjust both the width and the center of membership functions so that the tuned rule-based fuzzy controller can generate the desired performance. The effectiveness of the proposed algorithm is verified by computer simulation.

• Journal of the Korean Magnetic Resonance Society
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• v.1 no.2
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• pp.112-125
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• 1997

It has been demonstrated that mutant Hemoglobins (Hb) which have an altered ${\alpha}$1${\beta}$2 subunit interface can be designed. A compensatory mutation for a naturally occurring abnormal human Hb, Hb Kempsey (${\beta}$99Asp\longrightarrowAsn), has been designed, and this mutation allowed the molecule to regain its allosteric response. The calculated values for the difference in the free energy of cooperativity show excellent agreement with experimentally determined thermodynamic values, suggesting that the molecular dynamics simulation results can be used to obtain information about the specific interactions which contribute to the total free energy of cooperativity. These results provide encouragement to begin a systematic investigation of the molecular basis of the subunit interactions between the ${\alpha}$1 and ${\beta}$2 chains of Hb A by designing appropriate r Hbs. These studies could lead to the design of Hbs with desired cooperativity in the oxygenation process and to the restoration of functional properties of abnormal hemoglobins associated with hemoglobinopathies. Thus, the present results also have the implications in using gene therapy to treat patients with hemoglobinpathies.

• Hwankyungkyoyuk
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• v.21 no.4
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• pp.12-24
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• 2008

In this research, we have carried out an experiment with grade 10 students. Students will be choosing their roles and creating their own script in relation to the environmental problems such as the seriousness of global wanning and the mutation of ecosystem. Throughout this process, they will come up with a solution to the problem In addition, we will assess students' knowledge achievement as well as the changes in attitudes toward environment, and analyze whether the role-play method of education is efficient or not. According to the research result, we have confirmed that the method of role-play as a education tool was more efficient than the traditional lecturing method. Students experienced higher rate of knowledge acquisition and more optimistic effects on their attitudes toward the mutation of ecosystem and also the seriousness of the global wanning. Students also pointed out in the interview that the role-play allowed them to share their thoughts with other classmates, which were not carried out frequently in the traditional education system In addition, each member of groups could participate cooperatively with teammates, which ultimately helped them to develop scientific and introspective ways of thinking.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.187-190
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• 2003

Many manufacturing companies consider the integrated and concurrent scheduling because they need the global optimization technology that could manufacture various products more responsive to customer needs. In this paper, we propose an advanced scheduling model to generate the schedules considering resource constraints and precedence constraints in make-to-order (MTO) manufacturing environments. Precedence of work- in-process(WIP) and resources constraints have recently emerged as one of the main constraints in advanced scheduling problems. The advanced scheduling problems is formulated as a multiobjective mathematical model for generating operation schedules which are obeyed resources constraints, alternative workstations of operations and the precedence constraints of WIP in MTO manufacturing. For effectively solving the advanced scheduling problem, the multi-objective hybrid genetic algorithm (m-hGA) is proposed in this paper. The m-hGA is to minimize the makespan, total flow time of order, and maximum tardiness for each order, simultaneously. The m-hGA approach with local search-based mutation through swap mutation is developed to solve the advanced scheduling problem. Numerical example is tested and presented for advanced scheduling problems with various orders to describe the performance of the proposed m-hGA.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1092-1098
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• 2002

This paper discusses the composition of the theory of reinforcement teaming, which is applied in real-time teaming, and evolutionary strategy, which proves its the superiority in the finding of the optimal solution at the off-line teaming method. The individuals are reduced in order to team the evolutionary strategy in real-time, and new method that guarantee the convergence of evolutionary mutations are proposed. It is possible to control the control object varied as time changes. As the state value of the control object is generated, applied evolutionary strategy each sampling time because of the teaming process of an estimation, selection, mutation in real-time. These algorithms can be applied, the people who do not have knowledge about the technical tuning of dynamic systems could design the controller or problems in which the characteristics of the system dynamics are slightly varied as time changes. In the future, studies are needed on the proof of the theory through experiments and the characteristic considerations of the robustness against the outside disturbances.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.2
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• pp.50-58
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• 1998

Genetic Algorithm (GA) consists of selection, reproduction, crossover and mutation processes and many parameters including population size, generation number, the probability of crossover (Pc) and the probability of mutation (Pm). Determining values of the parameters is found critical in the whole optimization process and a sensitivity analysis with them seems mandatory. This paper tries to demonstrate such importance of sensitivity analysis of GA using an example water supply tunnel network of the New York City. For optimization of the network with GA, Pc and Pm vary from 0.5 to 0.9 by an increment of 0.1 and from 0.01 to 0.05 by an increment of 0.01, respectively, while fixing both the population size and the generation number to 100. This sensitivity analysis results in an optimum design of 22.3879 million dollars at the values of 0.8 and 0.01 for Pc and Pm, respectively. In addition, the probability of recombination (Pr) is introduced to check its applicability in the GA optimization of water distribution network. When Pr is 0.05 with the same values of Pc and Pm as above, the optimum design costs 20.9077 million dollars. This is lower than the cost of 22.3879 million dollars for the case of not using Pr by 6.6%. These results indicate that conducting a sensitivity analysis with parameter values and using Pr are useful in the optimization of WDN.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1729-1742
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• 2017

In designing System Protection Schemes (SPSs) in power systems, protecting transmission network against extreme undesired conditions becomes a significant challenge in mitigating the transmission line overloading. This paper presents an intelligent Special Protection and Control Scheme (SPCS) using of Differential Evolution with Adaptive Mutation (DEAM) approach to obtain the optimum generation rescheduling to solve the transmission line overloading problem in system contingency conditions. DEAM algorithm employs the attraction-repulsion idea that is applied in the electromagnetism-like algorithm to support the mutation process of the conventional Differential Evolution (DE) algorithm. Different N-1 contingency conditions under base and increase load demand are considered in this paper. Simulation results have been compared with those acquired from Genetic Algorithm (GA) application. Minimum severity index has been considered as the objective function. The final results show that the presented DEAM method offers better performance than GA in terms of faster convergence and less generation fuel cost. IEEE 30-bus test system has been used to prove the effectiveness and robustness of the proposed algorithm.