• Animal Bioscience
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• 제35권9호
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• pp.1340-1350
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• 2022

Objective: Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH. Methods: We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genome-wide selection signatures have been scanned with four methods: heterozygosity (H_P), fixation index (F_ST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (𝜃_π) ratio. Results: The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected. Conclusion: The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

• 환경영향평가
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• 제6권2호
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• pp.123-135
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• 1997

The solid waste incineration facilities which cause environmental pollution. And those are some kind of loathing facilities for residents who do not want it. This problem could be solved by location feasibility study. The purpose of location feasibility study was to determine one site out of three candidate sites. This study which was done by the law, environmental and economic factor was considered for optimum site selection. Comparative evaluation among the candidate sites was done by ordinal scale and thus the optimum site was selected.

• Communications for Statistical Applications and Methods
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• 제8권3호
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• pp.589-601
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• 2001

Probabilities of overfilling for model selection criteria are derived for several different situations. First, one candidate model with one extra variable is compared to the current model. This is expanded to m candidate models. We show that these comparisons are not independent and discuss ovefitting probabilities. Correlation between two F-tests is derived. Finally, probabilities are computed using the dependent F distributions and F distributions based on order statistics of independent Chi-squares.

• 환경위생공학
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• 제15권2호
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• pp.85-94
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• 2000

The comparative evaluation is the most effective method for site selection because the selection of waste treatment facility is to determine the optimum site out of limited candidate sites. This study adopted the ordinal scale evaluation, one of methods of comparative evaluation. The ordinal scale evaluation aims to determine the investigating items referring to the character of sites, to determine the importance factors for investigating items, and to determine the optimum site according to the quantitative evaluation. This study has focussed on reflecting the opinion of residents to the maximum extent with a weight on social and economic aspects, considering the state of confrontation against each other between the autonomous government organization and local residents, which is being emerged as a social issue relating to the evaluation rating on each item of site selection of an optimum site. Therefore, rational, and clear validity investigations and proper reduction of both time and expenses in site selection as well through this a study.

• 시스템엔지니어링학술지
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• 제9권1호
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• pp.55-63
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• 2013

Nuclear power plant site selection is a complex process and its successful completion is a critical milestone in the NPP development cycle. Proper siting of NPP will ensure public health and safety, environmental conservation, reduced project failure risks and a smooth NPP development process among other benefits. The objective of this paper is to demonstrate the application of systems engineering to the problem of NPP siting in Kenya. The siting process demonstrated in this paper includes stakeholder need analysis where stakeholders are identified and their needs concerning NPP site are elicited and converted into system functional requirements. A value model is then developed and potential sites iteratively subjected to three types of criteria i.e. exclusionary criteria, avoidance criteria and suitability criteria. This process is used to identify the candidate sites. An additive value model; multiple objectives Decision Analysis (MODA) is then used to calculate candidate solutions values. The site with the highest solution value score is selected. Sensitivity studies using different criterion weight sets (thereby reflecting different viewpoints) can be conducted to assess their effect on the selection of a preferred site and thereby lend additional credibility to the decision process.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권3호
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• pp.326-330
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• 2008

패턴인식 문제에 있어서 다수의 인식기를 사용하는 연구는 주로, 선택된 다수 인식기를 어떻게 결합할 것인가에 중점을 두어 왔으나, 최근에는 인식기 풀로부터 다수 인식기를 선택하려는 연구로 점차 진행되고 있다. 실제로 다수 인식기 시스템의 성능은 인식기들의 결합 방법은 물론, 선택되는 인식기에 의존한다. 따라서, 우수한 성능을 보이는 인식기 집합을 선택하는 것이 필요하며, 다수의 인식기를 선택하는데 있어서 정보이론에 기초한 접근 방법이 시도되었다. 본 논문에서는 인식기 간의 상호정보를 기반으로 인식기를 선택하여 인식기 집합을 구성하고, 다른 인식기 선택 방법들에 의해 구성된 인식기 집합과 그 성능을 비교해 보고자 한다.

• Journal of Dairy Science and Biotechnology
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• 제18권1호
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• pp.47-60
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• 2000

Over decades of work, the probiotic research has grown rapidly with a number of new cultures, which is claimed a variety of benefit. However, many of the specific effects attributed to the ingestion of probiotics remain convoluted and scientifically unsubstantiated. Accordingly, the scientific community faces a greater challenge and must objectively seek cause and effect relationships for many potential and currently investigated probiotic species. Rational selection and design of probiotics remains an important challenge and will require a solid information about the physiology and genetics of candidate strains relevant to their intestinal roles, functional activities, and interaction of with other resident micro flora. As far as beneficial culture of lactic acid bacteria (LAB) is concerned, simple, cost-effective, and exact identification of candidate strains is of foremost importance among others. Until recently, the relatedness of bacterial isolates has been determined sorely by testing for one or several phenotyphic markers, using methods such as serotyping, phage-typing, biotyping, and so forth. However, there are problems in the use of many of these phenotype-based methods. In contrast, some of newer molecular typing methods involving the analysis of DNA offer many advantages over traditional techniques. These DNA-based methods have the greater discriminatory power than that of phenotypic procedures. This review focuses on the importance and the basis of molecular typing methods along with some considerations on de-sign and selection of probiotic culture for human consumption.

• 대한전자공학회논문지
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• 제27권2호
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• pp.118-125
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• 1990

분산 컴퓨터 시스템에서 정보 화일을 효율적으로 관리, 운용하기 위한 화일 할당 문제의 최적해를 구하는 화일 할당 알고리듬을 제안한다. 컴퓨터 노드(site)가 많은 경우 화일 할당에 많은 시간이 소요되므로 선 할당(preassignment)을 수행하여 문제의 규모를 축소하고 계산시간을 개선한다. 할당이 진행중인 상태의 표시치(representative value)를 정확하게 나타내기 위해 기대값을 이용한 평가치 계산기법을 제안하고 빠른 시간에 최적 할당이 이루어지도록 후보 노드(candidate node)에 대한 선택기준(selection criteria)을 설정한다. 선택기준에 의해 각 노드의 화일 할당 여부를 결정하고 최종 평가치가 할당 상태의 전체 비용을 나타낸다. 제안한 알고리듬은 다항식 시간(polynomial time)알고리듬이며 여러 예제에 실현한 결과 할당 소요시간이 개선되고 기존의 할당 알고리듬과 비교하여 최적해를 구하는데 있어 우수함을 나타냈다.

• Journal of Communications and Networks
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• 제15권2호
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• pp.164-172
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• 2013

We consider the problem of secure and robust clustering for quantized target tracking in wireless sensor networks (WSN) where the observed system is assumed to evolve according to a probabilistic state space model. We propose a new method for jointly activating the best group of candidate sensors that participate in data aggregation, detecting the malicious sensors and estimating the target position. Firstly, we select the appropriate group in order to balance the energy dissipation and to provide the required data of the target in the WSN. This selection is also based on the transmission power between a sensor node and a cluster head. Secondly, we detect the malicious sensor nodes based on the information relevance of their measurements. Then, we estimate the target position using quantized variational filtering (QVF) algorithm. The selection of the candidate sensors group is based on multi-criteria function, which is computed by using the predicted target position provided by the QVF algorithm, while the malicious sensor nodes detection is based on Kullback-Leibler distance between the current target position distribution and the predicted sensor observation. The performance of the proposed method is validated by simulation results in target tracking for WSN.

• 품질경영학회지
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• 제41권1호
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• pp.109-118
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• 2013

혼합물 성분비와 공정변수들에 관한 실험 자료가 주어진 경우에, 주어진 실험 자료를 잘 설명하는 적절한 결합모형을 찾는 것은 중요한 과제이다. 우선 모형 선택 기준에 부합하는 시작모형의 후보들을 교적모형의 범주에서 찾고, 다음으로 선택된 시작모형을 완전모형으로 간주하여, 모형의 간결성의 원칙에 따라서 완전모형의 부분모형으로 구성된 적절한 결합모형들을 찾는데, 일반적으로 여러 개의 결합모형들이 추천된다. 주어진 실험 자료에 대한 적절한 모형으로 여러 개의 모형이 추천된 경우에, 엔지니어들의 실용적인 관심사는 각각의 결합모형에 대한 반응변수의 기대값의 예측치와 예측치의 표준편차의 추정치를 동시에 최적으로 하는 최적조건의 찾기이다. 이를 위한 실용적인 방법으로 반응변수가 여러 개인 다중 반응표면 분석에서 동시 최적화 기법을 활용한 최적조건을 찾는 방법을 제안하고, 잘 알려진 혼합물성분-공정변수 실험 자료에 대해서 Design Expert 8.0을 활용하여 적절한 결합모형들을 찾고, 이 모형들을 동시에 최적화하는 최적조건 찾기가 예시된다.