• IEIE Transactions on Smart Processing and Computing
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• 제5권6호
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• pp.445-453
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• 2016

Fixed robust routing is attracting attention as routing that achieves high robustness against changes in traffic patterns without conducting traffic measurement and performing dynamic route changes. Fixed robust routing minimizes the worst-case maximum link load by distributing traffic of every source-destination (s-d) router pair onto multiple candidate paths (multipath routing). Multipath routing, however, can result in performance degradation of Transmission Control Protocol (TCP) because of frequent out-of-order packet arrivals. In this paper, we first investigate the influence of multipath routing on TCP performance under fixed robust routing with a simulation using ns-2. The simulation results clarify that TCP throughput greatly degrades with multipath routing. We next propose a candidate path selection method to improve TCP throughput while suppressing the worst-case maximum link load to less than the allowed level under fixed robust routing. The method selects a single candidate path for each of a predetermined ratio of s-d router pairs in order to avoid TCP performance degradation, and it selects multiple candidate paths for each of the other router pairs in order to suppress the worst-case maximum link load. Numerical examples show that, provided the worst-case maximum link load is less than 1.0, our proposed method achieves about six times the TCP throughput as the original fixed robust routing.

• Journal of the Korean Statistical Society
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• 제35권3호
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• pp.261-280
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• 2006

We have developed a new model selection criteria, the partial intrinsic Bayes factor, which is designed for cases when we select a model among a small number of candidate models. For example, we can choose only a few candidate models after exploring scatter plots. By simulation study, we have showed that PIBF performs better than AIC, BIC and GCV.

• Communications for Statistical Applications and Methods
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• 제22권2호
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• pp.173-180
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• 2015

We propose a selection procedure of principal components in principal component regression. Our method selects principal components using variable selection procedures instead of a small subset of major principal components in principal component regression. Our procedure consists of two steps to improve estimation and prediction. First, we reduce the number of principal components using the conventional principal component regression to yield the set of candidate principal components and then select principal components among the candidate set using sparse regression techniques. The performance of our proposals is demonstrated numerically and compared with the typical dimension reduction approaches (including principal component regression and partial least square regression) using synthetic and real datasets.

• 대한공간정보학회지
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• 제14권1호
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• pp.29-36
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• 2006

변전소와 같은 사회적으로 위험물로 인식되는 공공시설물에 대한 부지를 선정 할 경우에는 다른 어떤 시설물보다 부지 선정시 과학적이고 공정한 과정이 필요하다. 본 연구에서는 계층분석과정과 GIS의 공간분석 기능을 통하여 경기도 남부 지역의 변전소 선정에 요구되는 자료들을 축척 1/5,000 수치지도 및 현지 조사로부터 취득하여 최적의 위치를 안전성, 국가토지이용, 경제성 및 환경보전측면을 고려하여 선정하였다. 실제 처리과정에서 대상지역 전체에 대하여 1차적으로 반경 1.5km의 3개 지역에 대한 우선후보군을 선정하였고 선정된 후보군에 대하여 2차 현지 상세조사를 토대로 최종적으로 변전소가 건설될 4개의 후보 부지에 대한 다원 평가를 실시하였으며 정량적 분석을 통한 위치의 적정성에 대한 결론을 도출 하였다. 적지분석 결과 1후보 부지인 경기도 안성시 양성면 장서리 지역이 최적지로 나타났으며 다른 후보 부지들도 대체적으로 좋은 입지여건을 갖는 것으로 나타났다.

• 농업과학연구
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• 제50권4호
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• pp.953-966
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• 2023

As the importance of renewable energy diffusion spreads, promotion of sustainable renewable energy projects such as agrivoltaics is expected to accelerate. Furthermore, to promote agrivoltaics projects, it must be considered the legislation related to agrivoltaics and Chungnam Province's local policy. This research focuses on the selection of the most suitable sites for agrivoltaics installations in Chungnam Province in South Korea. Therefore, the process of this research was as follows. First, the legislation related to agrivoltaics and local policy in Chungnam Province were identified. Second, it employs an analytic hierarchy process (AHP) to consider important criteria and their weights for site selection. Third, based on the weights calculated AHP, geographic information system (GIS) was performed to select most suitable location selection of agrivoltaics installations in Chungnam Province. The analysis identified approximately 60 promising most suitable location for agrivoltaics installations in Chungnam Province, primarily in the northern part of Chungnam Province. These areas are expected to meet electricity demands in nearby regions since these are relatively adjacent to Gyeonggi Province. According to the results of research, policy suggestions related to agrivoltaics were presented separately into the agricultural sector and the electricity power sector. The study's results serve as a valuable resource for future national-level candidate site selection for agrivoltaics projects.

• 한국항해항만학회지
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• 제34권1호
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• pp.59-64
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• 2010

본 연구는 마리나 건설 최적의 대상지를 결정하기 위하여 여러 가능해역 중에서 최적의 장소를 결정하는 것이다. 마리나 건설 후보지 선정 문제를 다루기 위해서 여수시 인근의 10개의 후보지를 대상으로 10개의 결정 요인들을 분석하여 최적의 장소를 선정한다. 본 논문에서는 가장 합리적인 장소를 결정하기 위하여 새로운 모델인 0-1정수 최적계획모형이 제안된다. 제안된 모형은 지금까지 최적 마리나 시설 분석 문제에 적용된 사례가 없다. 본 논문은 가장 합리적인 장소를 결정하는데 기여할 뿐만 아니라 제안된 모형은 타 지역의 마리나 시설 건설 후보지 선정 문제에도 적용할 수 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권2호
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• pp.149-153
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• 2017

Objective: This study was to determine the relationship between estimated breeding value and phenotype information after farrowing when juvenile selection was made in candidate pigs without phenotype information. Methods: After collecting phenotypic and genomic information for the total number of piglets born by Landrace pigs, selection accuracy between genomic breeding value estimates using genomic information and breeding value estimates of best linear unbiased prediction (BLUP) using conventional pedigree information were compared. Results: Genetic standard deviation (${\sigma}_a$) for the total number of piglets born was 0.91. Since the total number of piglets born for candidate pigs was unknown, the accuracy of the breeding value estimated from pedigree information was 0.080. When genomic information was used, the accuracy of the breeding value was 0.216. Assuming that the replacement rate of sows per year is 100% and generation interval is 1 year, genetic gain per year is 0.346 head when genomic information is used. It is 0.128 when BLUP is used. Conclusion: Genetic gain estimated from single step best linear unbiased prediction (ssBLUP) method is by 2.7 times higher than that the one estimated from BLUP method, i.e., 270% more improvement in efficiency.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권7호
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• pp.1252-1273
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• 2011

In Web Service Composition (WSC) area, services selection aims at selecting an appropriate candidate from a set of functionally-equivalent services to execute the function of each task in an abstract WSC according to their different QoS values. In despite of many related works, few of previous studies consider transactional constraints in QoS-aware WSC, which guarantee reliable execution of Composite Web Service (CWS) that is composed by a number of unpredictable web services. In this paper, we propose a novel global selection-optimal approach in WSC by considering both transactional constraints and end-to-end QoS constraints. With this approach, we firstly identify building rules and the reduction method to build layer-based Directed Acyclic Graph (DAG) model which can model transactional relationships among candidate services. As such, the problem of solving global optimal QoS utility with transactional constraints in WSC can be regarded as a problem of solving single-source shortest path in DAG. After that, we present Graph-building algorithms and an optimal selection algorithm to explain the specific execution procedures. Finally, comprehensive experiments are conducted based on a real-world web service QoS dataset. The experimental results show that our approach has better performance over other competing selection approaches on success ratio and efficiency.

• International journal of advanced smart convergence
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• 제12권1호
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• pp.208-219
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• 2023

Recently, as mega-urbanization progresses, urban logistics centered on large cities is growing rapidly, and logistics transportation is increasing due to the lack of logistics infrastructure and the operation of a delivery system using cargo trucks in the city center. being cited as a cause. In order to solve this problem, domestic researchers are conducting research on the development of " Urban Underground railway Logistics System" that minimizes the initial infrastructure construction cost by utilizing the existing urban railway facilities in the city. Therefore, this paper analyzed the usage environment of the actual urban railway station to which the system will be applied in order to derive candidates for the test bed selection of "Urban Underground railway Logistics System". The evaluation criteria for test bed candidate role selection were established, and the candidate group derived from the Brown & Gibson model was used to evaluate the candidate group and derive the candidate role. A review of the results was conducted to contribute to the establishment of a test bed for the " Urban Underground railway Logistics System" under development.

• 한국산업보건학회지
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• 제24권4호
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• pp.587-612
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• 2014

Objectives: There is requirement to select candidate materials for chronic inhalation/carcinogenicity testing, so we would like to set the priority of candidate materials. Methods and Results: We recommend the priorities for candidate materials based on the chemicals stipulated in the Occupational Safety and Health Act(OSHAct) and the Toxic Chemicals Control Act(TCCA) in Korea. Conclusions: We presented candidate chemicals consisting of solids(powders), gases and liquids(Such as organic solvents) with priorities.