• 한국자원식물학회지
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• 제28권6호
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• pp.697-703
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• 2015

Twenty apple germplasm accessions from the Korean Genebank were successfully cryopreserved using two-step freezing to back up genetic resources maintained by field collections. This study examined the morphological and genetic stability of cryopreserved dormant apple buds that were stored in liquid nitrogen, and then rewarmed and regrown. Whole plants were regenerated directly from dormant buds through budding without an intermediary callus phase. The cryopreserved buds produced high levels of shoot formation (76.2-100%), similar to those of noncryopreserved buds (91.3-100%), with no observed differences between cryopreserved and noncryopreserved materials. Three of the twenty cryopreserved apple germplasm accessions were used to assess morphological and genetic stability. No differences in morphological characteristics including shoot length, leaf shape, leaf width/length ratio, and root length were observed between controls (fresh control and noncryopreserved) and cryopreserved plantlets. The genetic stability of regenerants (before and after cryopreservation) was investigated using inter simple sequence repeat (ISSR) markers. The ISSR markers produced 253 bands using four primers, ISSR 810, SSR 835, ISSR 864, and ISSR 899. These markers showed monomorphic banding patterns and revealed no polymorphism between the mother plant and regenerants before and after cryopreservation, suggesting that cryopreservation using two-step freezing does not affect the genetic stability of apple germplasm. These results show that two-step freezing cryopreservation is a practical method for long-term storage of apple germplasms.

• Geomechanics and Engineering
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• 제1권1호
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• pp.85-96
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• 2009

The radius and coordinate of sliding circle are taken as searching variables in slope stability analysis. Genetic algorithm is applied for searching for critical factor of safety. In order to search for critical factor of safety in slope stability analysis efficiently and in a robust manner, some improvements for simple genetic algorithm are proposed. Taking the advantages of efficiency of neighbor-search of the simulated annealing and the robustness of genetic algorithm, a hybrid optimization method is presented. The numerical computation shows that the procedure can determine the minimal factor of safety and be applied to slopes with any geometry, layering, pore pressure and external load distribution. The comparisons demonstrate that the genetic algorithm provides a same solution when compared with elasto-plastic finite element program.

• 전기학회논문지P
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• 제64권1호
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• pp.14-17
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• 2015

This paper presents a analysis method for power system stability using a Modified Genetic-based Power System Stabilizer(MGPSS). The proposed MGPSS parameters are optimized using Modified Genetic Algorithm(MGA) in order to maintain optimal operation of generator under the various operating conditions. To improve the convergence characteristics, real variable string is adopted. The results tested on a single machine infinite bus system verify that the proposed controller has better power system stability than conventional controller.

• 대한전기학회논문지:전력기술부문A
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• 제48권3호
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• pp.247-256
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• 1999

In this paper, a methodology for optimal design of PID controller using the modified genetic algorithm has been proposed to improve the transient stability at system fault in HVDC transmission system, mathematical model preparation for stability analysis, and supplementary signal control by an optimal PID controller using the modified genetic algorithm(MGA). The propriety was verified through computer simulations regarding transient stability. It means that the application of MGA-PID controller in HVDC transmission system can contribute the propriety to the improvement of the transient stability in HVDC transmission system and the design of MGA-PID controller has been proved indispensible when applied to HVDC transmission system.

• Journal of Forest and Environmental Science
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• 제26권1호
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• pp.31-36
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• 2010

Sixteen microsatellite markers (simple sequence repeat (SSR) markers) were employed to examine the genetic stability of 27 randomly chosen date palm (Phoenix dactylifera L.) plants produced through somatic embryogenesis with upto forty two in vitro subcultures. No microsatellite DNA variation was observed among all micropropagated plants. Our results indicate that the micropropagation protocol used for rapid in vitro multiplication is appropriate and suitable for clonal propagation of date palm and corroborated that somatic embryogenesis can also be used as one of the safe modes for production of true-to-type plants of date palm. This is the first report on the use of microsatellite DNA markers to establish the genetic stability in micropropagated date palm plants.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2763-2765
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• 2003

Generally, we made use of PID control for torque control, speed control and stability, Hence, dynamic characteristic of DC motor has been studied for stable drive and accurate speed control by many engineers. But, in this paper, we applied genetic algorithm to current control for robust control and stability In conclusion, we prove that current control of genetic algorithm can be high efficiency.

• 한국지반공학회논문집
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• 제18권6호
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• pp.117-127
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• 2002

사면의 파괴면 형태를 간단한 비선형 함수로 모델링하여 해석하는 결정론적인 사면안정 해석은 지층의 복합 특성과 불연속적인 특성을 효과적으로 반영하지 못하는 단점이 있다. 따라서, 본 연구에서는 결정론적인 방법 보다 지층의 제반조건들을 다양하게 반영할 수 있는 임의 탐색기법인 유전자 알고리즘을 이용한 사면안정 해석 방법을 제시하였다. 제시된 방법의 적합성을 확인하기 위해 단일지층 및 복합지층을 대상으로 하여 제안된 방법과 결정론적인 방법을 비교.검토하였으며, 검토결과 유전자 알고리즘을 이용한 사면안정해석 방법의 적용성을 검증할 수 있었다. 또한 제시된 사면안정 해석 방법에 강우강도에 따른 지하수위의 변화 예측모델을 적용하여 보다 합리적인 사면안정 해석 방법을 제시하였다.

• 한국항해항만학회지
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• 제26권2호
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• pp.189-192
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• 2002

우리나라 대부분의 어선은 침수 및 전복에 의해 야기되는 해양사고에 있어 그 빈도가 높으며, 특히 24m이하의 소형어선에서 두드러진다. 그럼에도 불구하고 소형어선에 대한 복원성 기준이 없을 뿐 아니라 소형어선의 복원성 자료를 찾기란 그리 쉽지 않다. 이에 본 연구에서는 90년 이후 표준어선으로 고시되어 건조 실적이 있는 실적선 10척에 대해 계측된 자료를 활용하여 이를 기초로 Genetic Programming을 이용한 GM 추정식을 도출하였다. 또한 국외 복원성 기준과 GP 추정식을 이용 각각에 대해서 GM을 평가하여, Genetic Programming에 의한 GM추정의 타당성을 보였다. 하지만, 이러한 결과값이 사용되기 위해서는 보다 많은 실적선 Data를 이용한 추론이 요구된다.

• 한국미생물·생명공학회지
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• 제19권3호
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• pp.215-221
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• 1991

YIp5를 사용하여 Cephalosporium acremonium ATCC 2033으로부터 Saccharomyces cerevisiae SHY3에서 발현되는 자율복제 기점 (ARS)를 분리하였다. 자율복제 기점을 갖는 40종의 vector 가운데 가장 안정성 (stability)이 높은 plasmid를 pCY-2라 명명하였으며 pCY-2는 C.acremonium에서 유래하는 3.7kb의 단편을 갖고 있었다. 또 Southern hybridization과 재형질전환을 통해 pCY-2가 효모내에서 자율적으로 복제되고 있다는 것을 확인하였다. 또한 pCY-2는 형질전환율과 안정성에 있어 효모의 ARS를 갖는 YRp7 vector보다 우수하였다.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권1호
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• pp.135-142
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• 2012

In this paper, optimal selection of the unified power flow controller (UPFC) damping controller parameters in order to improve the power system dynamic response and its stability based on two modified intelligent algorithms have been proposed. These algorithms are based on a modified intelligent particle swarm optimization (PSO) and continuous genetic algorithm (GA). After extraction of UPFC dynamic model, intelligent PSO and genetic algorithms are used to select the effective feedback signal of the damping controller; then, to compare the performance of the proposed UPFC controller in damping the critical modes of a single-machine infinite-bus (SMIB) power system, the simulation results are presented. The comparison shows the good performance of both presented PSO and genetic algorithms in an optimal selection of UPFC damping controller parameters and damping oscillations.