• Journal of Korea Water Resources Association
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• v.54 no.9
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• pp.643-656
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• 2021

Recently, water supply management technology is highly developed, and a computer simulation model plays a critical role for estimating hydraulics and water quality in water distribution networks (WDNs). However, a simulation of complex large water networks is computationally intensive, especially for the water quality simulations, which require a short simulation time step and a long simulation time period. Thus, it is often prohibitive to analyze the water quality in real-scale water networks. In this study, in order to improve the computational efficiency of water quality simulations in complex water networks, a hierarchical water-quality-simulation technique was proposed. The water network is hierarchically divided into two sub-networks for improvement of computing efficiency while preserving water quality simulation accuracy. The proposed approach was applied to a large-scale real-life water network that is currently operating in South Korea, and demonstrated a spatiotemporal distribution of chlorine concentration under diverse chlorine injection scenarios.

• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.667-675
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• 2011

As the annual growth rate of port handling container volume in Korea has faced slowdown, this paper attempts to find strategies for the domestic container terminal operators in order to enhance competitiveness. For this, the model of using AHP and the fuzzy set theory is used for evaluating competitiveness between domestic and global container terminal operators. The evaluation model hierarchy is developed based on SERM(subject-environment-resource-mechanism) theory of business strategy. The results show domestic operators are ranked lower than global player so that they particularly pay attention to the areas of scale of economy, business diversification, and globalization strategy.

• Journal of Digital Convergence
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• v.8 no.3
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• pp.19-37
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• 2010

One of the core issues in the realization of e-government is the effective implementation of a website. The current trend of e-government is developing individual web sites and portals, covering such fields as education, tax, economics, real estate, travel, and health. Evaluating e-government web sites is essential for improving web sites. These principles can be included in usability in a broader concept. Website usability has attracted considerable research on website evaluation and has been regarded as one of the most important criteria for measuring and evaluating websites. Usable e-government web sites make citizens willing to search for helpful information or solve their civil applications. The objective of this paper is to suggest an Analytic Hierarchy Process (AHP) method for evaluating e-government web sites. The proposed AHP method has two special characteristics compared to general AHP approaches. First, all citizens who are e-government users can evaluate both the usability criteria and the web sites, but the weighting mechanism differs between criteria and web sites. Secondly, a pairwise comparison is time-consuming and not cost effective with many criteria. Therefore for evaluating a website with respect to a sub-criterion, we develop checklist items as measure scales with a seven-point rating. This method is efficient as it enable us to avoid the pairwise comparison mechanism between sub-criteria. A new computation procedure for the AHP is developed that combines and synthesizes priorities of portals in the case that two decision maker groups are involved.

• The Transactions of the Korea Information Processing Society
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• v.6 no.6
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• pp.1571-1580
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• 1999

When a hierarchical structure is derived from data set for data mining and machine learning, using a conceptual clustering algorithm, one of the unsupervised learning paradigms, it is not unusual to have a different set of outcomes with respect to the order of processing data objects. To overcome this problem, the first classification process is proceeded to construct an initial partition. The partition is expected to imply the possible range in the number of final classes. We apply center sorting to the data objects in the classes of the partition for new data ordering and build a new partition using ITERATE clustering procedure. We developed an algorithm, REIT that leads to the final partition with stable and best partition score. A number of experiments were performed to show the minimization of order bias effects using the algorithm.

• Journal of Service Research and Studies
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• v.6 no.4
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• pp.35-45
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• 2016

This study derives the critical success factors through discussion of expert group in operation stage of ERP system that is suggested by the prior study. Relative importance of the derived critical success factors are analyzed using Analytic Hierarchy Process(AHP). In the first layer of the hierarchy, organizational/ human resource factors are appeared to be the most important factors. In the second layer of the hierarchy, CEO support is evaluated as the most important success factor considering the weight of the 1st layer of the hierarchy followed by process optimization, change management, support of the operation department, and maintenance of process innovation organization. This study suggests that, in order to maximize the introducing effect, continuous support and attention of management is not the only requirement. Proper change management to handle the internal environment change caused by the introduction of the ERP system, support of operation department dedicated to ERP system, and separate department for continuous innovation of process are also required.

• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.21-28
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• 2011

Recently, the Project Financing industry has appeared the various change of the development environment in the rapid growth. So the Project Financing company has been trying to search Project Financing able to success and they are performing diversified researching to prepare the judgment ground of success from initial stage of development. The aim of this study is to find success factors which is in the Project Financing through collecting opinion of specialist and talking survey to people employed in Project Financing development field. Consequently, we indicate success factors using Analytic Hierarchy process (AHP) and make out success factors for the Project Financing. Furthermore, we suggest the way which is able to apply factors objectified so that exceed the development success Project Financing objectively.

• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.95-103
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• 2010

The purpose of this study is to propose a decision-making technique for selecting waterproofing methods using the Analytic Hierarchy Process (AHP) technique. In this study, a questionnaire survey was given to a group of specialists, which included design specialists, construction specialists, and maintenance specialists, regarding their experience with roof waterproofing methods. The 1st level hierarchy of the questionnaire survey addressed the function, economics, and maintenance of each of the roof waterproofing methods. The rank of 13 items of questionnaire, which is the 2nd level hierarchy of the questionnaire survey, is calculated using Expert Choice Solution. The analysis of questionnaire survey shows that each specialist selects different roof waterproofing methods, and all specialists make much of waterproof performance.

• The Journal of Information Technology and Database
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• v.4 no.2
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• pp.123-140
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• 1998

동일하거나 유사한 기능을 수행하는 소프트웨어 제품들 중에서 사용자 요구사항에 가장 적합한 제품을 결정하기 위하여 측정과 평가 및 선정을 실시하는 것을 매우 중요한 일이다. 이러한 소프트웨어 제품의 평가와 선정은 대량 구매시 객관성 확보를 위해 특히 중요하다. 소프트웨어 제품의 평가를 위한 절차는 평가 대상 제품의 속성 결정과 측정, 속성의 중요도에 따른 가중치 부여, 그리고 평가와 선정 모형을 통한 최적제품의 선정이나 우선순위의 결정이다. 본 연구에서는 이러한 절차에 따른 가중치 부여 방법으로는 계층적 분석과정을 이용하고, 제품의 평가와 선정 방법으로는 4개 보상모형과 7개 비보상모형, 그리고 4개의 DEA(Data Evelopment Analysis)모형을 종합적으로 설명한다. 또한 본 연구에서는 위의 15개 평가와 선정모형을 사용하여 Infoworld(Jan.1997)에서 발표한 '문서 작업흐름 관리' 소프트웨어 제품의 속성에 대한 측정결과를 가지고 모형별 적용 결과를 분석한다.

• Journal of Broadcast Engineering
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• v.1 no.2
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• pp.165-175
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• 1996

In this paper, the image segmentation method based on the hierarchical pyramid image structure of reduced resolution versions of the image for solving the problems in the conventional methods is presented. This method is described the object detection and delineation by statistical approach. In the object detection method, IFSVR( Inverse-father-son variance ratio) method and FSVR(father-son variance ratio ) method are proposed for solving clustering validity problem occurred In the hierarchical pyramid image structure. An optimal object pixel Is detected at some level by this method. In the object delineation method, the iterative algorithm by top-down traversing method is proposed for moving the optimal object pixel to levels of higher resolution. Using the computer simulation, the results by the proposed statistical methods and object traversing method are investigated for the binary Image and the real image. At the results of computer simulation, the proposed methods of image segmentation based on the hierarchical pyramid Image structure seem to have useful properties and deserve consideration as a possible alternative to existing methods of image segmentation. The computation for the proposed method is required 0(log n) for n${\times}$n input image.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3D
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• pp.347-356
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• 2009

This paper is described clustering analysis of traffic characteristics-based highway classification in order to deviate from methodologies of existing highway functional classification. This research focuses on comparing the clustering techniques performance based on the total within-group errors and deriving the optimal number of cluster. This research analyzed statistical clustering method (Hierarchical Ward's minimum-variance method, Nonhierarchical K-means method) and Kohonen self-organizing maps clustering method for highway characteristic classification. The outcomes of cluster techniques compared for the number of samples and traffic characteristics from subsets derived by the optimal number of cluster. As a comprehensive result, the k-means method is superior result to other methods less than 12. For a cluster of more than 20, Kohonen self-organizing maps is the best result in the cluster method. The main contribution of this research is expected to use important the basic road attribution information that produced the highway characteristic classification.