• 한국작물학회지
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• 제48권4호
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• pp.316-321
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• 2003

Analysis of breeding gains in grain yield has been intensively conducted in wheat, barley, oat, maize, and soybean. Such information is limited in rice. The objective of this study was to compare the breeding gains and cultural gains contributed to yield gains of Korean rice varieties since early 1900s. Two sets of yield data were used for analysis; the historical yield data of 1908 for old japonica cultivars, and present yield data in the years from 1996 to 1998 for the six cultivars, consisting of previous two old cultivars and four contemporary cultivars. The old cultivars were two native cultivars, Jodongi and Damageum, while contemporary cultivars were two premium quality japonica cultivars, Hwaseongbyeo and Dongjinbyeo, and two Tongil-type cultivars, high yielding cultivars developed from indica/japonica hybridization, Milyang23 and Dasanbyeo. The yield differences of old cultivars between the experiments in 1908 and the experiments from 1996 to 1998 were estimated as cultural gains (1.84 tons $\textrm{ha}^{-1}$) due to the improvement of cultivation technology. Yield differences between the old cultivars and contemporary cultivars were considered total yield gains during the periods. These were 2.51 tons $\textrm{ha}^{-1}$ for japonica cultivars and 3.81 tons $\textrm{ha}^{-1}$ for Tongil-type cultivars. From these data, the genetic gain of 0.67 tons $\textrm{ha}^{-1}$ and 1.97 tons $\textrm{ha}^{-1}$ were estimated for japonica cultivars and Tongil-type cultivars respectively. The ratio between cultural gain and genetic gain appeared to be 2.7:1 for japonica cultivars and 1:1 for Tongil-type cultivars. This analysis clearly showed the higher genetic contribution in Tongil-type cultivars than in japonica cultivars, suggesting a guideline to be used when planning new yield improvement programs. Additional implication has emerged when a better yield response to modem cultivation technology was found in one of the old cultivars, suggesting the combined improvement between breeding and cultural improvement is necessary for attaining the maximum yield capacity of a crop.

• 전자공학회논문지CI
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• 제41권4호
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• pp.67-72
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• 2004

본 논문에서는 네트워크기반의 클라이언트-서버모델에서 병렬유전자알고리즘의 최적해 수렴속도를 향상시키는 방법을 제안한다. 전역 최적해를 지역 엘리트의 평가만으로 구하는 기존의 방법과는 달리 제안한 방법은 서버에서 지역 엘리트의 평가를 통해 전역 최적해를 구하고 유휴시간에 유전자알고리즘을 적용하여 전역 최적해의 적합도를 개선한다. 서버에서 개선된 전역 최적해를 클라이언트의 유전자알고리즘에서 사용하므로 전체 알고리즘의 최적해 수렴속도가 향상된다 Fmax(g)는 g번째 세대의 최대 적합도, G는 서버에서 개선되는 세대수일 때, 지역 최적해의 이주 시 서버에서 개선되는 적합도는 (equation omitted)(F/sub max/(g)-F/sub max/(g-1)) 이다. 여기서 클라이언트의 수가 증가하면 G가 작아져서 적합도 개선치는 줄어드나 기존의 방법보다 적합도가 개선됨을 확인할 수 있었다.

• Animal Bioscience
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• 제37권2_spc호
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• pp.370-384
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• 2024

Rumen microbiota play a central role in the digestive process of ruminants. Their remarkable ability to break down complex plant fibers and proteins, converting them into essential organic compounds that provide animals with energy and nutrition. Research on rumen microbiota not only contributes to improving animal production performance and enhancing feed utilization efficiency but also holds the potential to reduce methane emissions and environmental impact. Nevertheless, studies on rumen microbiota face numerous challenges, including complexity, difficulties in cultivation, and obstacles in functional analysis. This review provides an overview of microbial species involved in the degradation of macromolecules, the fermentation processes, and methane production in the rumen, all based on cultivation methods. Additionally, the review introduces the applications, advantages, and limitations of emerging omics technologies such as metagenomics, meta-transcriptomics, metaproteomics, and metabolomics, in investigating the functionality of rumen microbiota. Finally, the article offers a forward-looking perspective on the new horizons and technologies in the field of rumen microbiota functional research. These emerging technologies, with continuous refinement and mutual complementation, have deepened our understanding of rumen microbiota functionality, thereby enabling effective manipulation of the rumen microbial community.

• Journal of Mechanical Science and Technology
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• 제16권8호
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• pp.1033-1038
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• 2002

Genetic alsorithm (GA) , compared to the gradient-based optimization, has advantages of convergence to a global optimized solution. The genetic algorithm requires so many number of analyses that may cause high computational cost for genetic search. This paper proposes a personal computer network programming based on TCP/IP protocol and client-server model using socket, to improve processing speed of the genetic algorithm for optimization of composite laminated structures. By distributed processing for the generated population, improvement in processing speed has been obtained. Consequently, usage of network-based genetic algorithm with the faster network communication speed will be a very valuable tool for the discrete optimization of large scale and complex structures requiring high computational cost.

• 한국경영과학회지
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• 제26권2호
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• pp.59-68
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• 2001

The job shop scheduling problem is not only NP-hard, but is one of the well known hardest combinatorial optimization problems. The goal of this research is to develop an efficient scheduling method based on hybrid genetic algorithm to address job shop scheduling problem. In this scheduling method, generating method of initial population, new genetic operator, selection method are developed. The scheduling method based on genetic algorithm are tested on standard benchmark job shop scheduling problem. The results were compared with another genetic algorithm0-based scheduling method. Compared to traditional genetic, algorithm, the proposed approach yields significant improvement at a solution.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1305-1308
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• 2003

A new technique is presented to construct a predictive model of plasma etch process. This was accomplished by combining a backpropagation neural network (BPNN) and a genetic algorithm (GA). The predictive model constructed in this way is referred to as a GA-BPNN. The GA played a role of controlling training factors simultaneously. The training factors to be optimized are the hidden neuron, training tolerance, initial weight magnitude, and two gradients of bipolar sigmoid and linear functions. Each etch response was optimized separately. The proposed scheme was evaluated with a set of experimental plasma etch data. The etch process was characterized by a $2^3$ full factorial experiment. The etch responses modeled are aluminum (A1) etch rate, silica profile angle, A1 selectivity, and dc bias. Additional test data were prepared to evaluate model appropriateness. The GA-BPNN was compared to a conventional BPNN. Compared to the BPNN, the GA-BPNN demonstrated an improvement of more than 20% for all etch responses. The improvement was significant in the case of A1 etch rate.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1467-1481
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• 2000

The Korean cattle industry is important to farming households, the national economy, and the security of foodstuffs in Korea. Since Korean cattle have had inferior ability to produce meat, the Korean cattle industry aimed to improve the meat production ability and to increase numbers to meet the demand from the growing beef cattle market in Korea. This paper reviews the history of the Korean cattle industry and surveys the efforts devoted to improve genetic abilities of the Korean cattle. Discussed are current situations of the Korean cattle industry, projects related to improvement of Korean cattle, Korean cattle's genetic characteristics of economic traits, and some issues to deal with.

• 농업생명과학연구
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• 제44권2호
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• pp.17-28
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• 2010

본 연구에서는 2000년부터 2008년 사이에 출생한 Duroc종, Landrace종 및 Yorkshire종의 GGP (Great Grand Parents) 종돈 31,455두의 농장검정자료를 이용하여 단변량 모체효과 모형에 의한 돼지의 경제형질에 대한 유전모수 및 유전력 추정을 통해 모체효과가 돼지의 경제형질에 미치는 영향에 대하여 알아보았다. 조사된 모든 형질에서 각 요인에 대한 유의성을 검정한 결과 모든 형질에 있어서 품종, 성, 출생년도, 출생계절 및 산차의 효과는 고도의 유의성이 인정되었고 (p<0.01), 모체효과 모형을 이용하였을 때 각 품종별 형질에 대해 추정된 상가적 유전 분산과 모체 유전 분산사이에 부 (-)의 공분산이 존재하고, 이들의 유전 상관도 대부분 강한 부 (-)의 상관관계를 보여 품종, 형질 및 개량 방향에 따라 모체 효과뿐만 아니라 상가적 효과와 모체 효과간의 상관관계도 적절히 고려한다면 좀 더 효율적인 개량효과를 거둘 수 있을 것으로 사료된다.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.254-254
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• 2005

• Asian-Australasian Journal of Animal Sciences
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• 제25권6호
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• pp.751-757
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• 2012

In order to develop specific genetic markers and determine the genetic diversity of Bangladeshi native cattle (Pabna, Red Chittagong) and exotic breeds (Sahiwal), randomly amplified polymorphic DNA (RAPD) analysis was performed using 12 primers. Genomic DNA was extracted from 20 cattle (local and exotic) blood samples and extracted DNA was observed by gel electrophoresis. Among the random primers three were matched and found to be polymorphic. Genetic relations between cattle's were determined by RAPD polymorphisms from a total of 66.67%. Statistical analysis of the data, estimating the genetic distances between cattle and sketching the cluster trees were estimated by using MEGA 5.05 software. Comparatively highest genetic distance (0.834) was found between RCC-82 and SL-623. The lowest genetic distance (0.031) was observed between M-1222 and M-5730. The genetic diversity of Red Chittagong and Sahiwal cattle was relatively higher for a prescribed breed. Adequate diversity in performance and adaptability can be exploited from the study results for actual improvement accruing to conservation and development of indigenous cattle resources.