• Title/Summary/Keyword: Selection Process

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Selecting Climate Change Scenarios Reflecting Uncertainties (불확실성을 고려한 기후변화 시나리오의 선정)

  • Lee, Jae-Kyoung;Kim, Young-Oh
    • Atmosphere
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    • v.22 no.2
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    • pp.149-161
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    • 2012
  • Going by the research results of the past, of all the uncertainties resulting from the research on climate change, the uncertainty caused by the climate change scenario has the highest degree of uncertainty. Therefore, depending upon what kind of climate change scenario one adopts, the projection of the water resources in the future will differ significantly. As a matter of principle, it is highly recommended to utilize all the GCM scenarios offered by the IPCC. However, this could be considered to be an impractical alternative if a decision has to be made at an action officer's level. Hence, as an alternative, it is deemed necessary to select several scenarios so as to express the possible number of cases to the maximum extent possible. The objective standards in selecting the climate change scenarios have not been properly established and the scenarios have been selected, either at random or subject to the researcher's discretion. In this research, a new scenario selection process, in which it is possible to have the effect of having utilized all the possible scenarios, with using only a few principal scenarios and maintaining some of the uncertainties, has been suggested. In this research, the use of cluster analysis and the selection of a representative scenario in each cluster have efficiently reduced the number of climate change scenarios. In the cluster analysis method, the K-means clustering method, which takes advantage of the statistical features of scenarios has been employed; in the selection of a representative scenario in each cluster, the selection method was analyzed and reviewed and the PDF method was used to select the best scenarios with the closest simulation accuracy and the principal scenarios that is suggested by this research. In the selection of the best scenarios, it has been shown that the GCM scenario which demonstrated high level of simulation accuracy in the past need not necessarily demonstrate the similarly high level of simulation accuracy in the future and various GCM scenarios were selected for the principal scenarios. Secondly, the "Maximum entropy" which can quantify the uncertainties of the climate change scenario has been used to both quantify and compare the uncertainties associated with all the scenarios, best scenarios and the principal scenarios. Comparison has shown that the principal scenarios do maintain and are able to better explain the uncertainties of all the scenarios than the best scenarios. Therefore, through the scenario selection process, it has been proven that the principal scenarios have the effect of having utilized all the scenarios and retaining the uncertainties associated with the climate change to the maximum extent possible, while reducing the number of scenarios at the same time. Lastly, the climate change scenario most suitable for the climate on the Korean peninsula has been suggested. Through the scenario selection process, of all the scenarios found in the 4th IPCC report, principal climate change scenarios, which are suitable for the Korean peninsula and maintain most of the uncertainties, have been suggested. Therefore, it is assessed that the use of the scenario most suitable for the future projection of water resources on the Korean peninsula will be able to provide the projection of the water resources management that maintains more than 70~80% level of uncertainties of all the scenarios.

A Study on the Development of Evaluation Model for Selecting a Standard for DITA using AHP (AHP를 이용한 국방정보기술표준 선정 평가 모델 개발에 관한 연구)

  • Kim, Ja-Hee;Kim, Woo-Je;Cho, Hyun-Ki;Lee, Eun-Young;Seo, Min-Woo
    • IE interfaces
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    • v.25 no.1
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    • pp.96-105
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    • 2012
  • Recently, the interoperability has become more important to enhance the net-centric capabilities of the warfighter. DITA (Defense Information Technical stAndard) is the set of IT standards for improving interoperability, scalability, effectiveness, and efficiency. In this paper, we analyzed the standardizing process to derive the selection criteria and structurized the derived selection criteria using the KJ (Kawakita Jiro) method. Finally, we developed an evaluation model for selecting a standard for DITA using AHP (Analytic Hierarchy Process). As a result, we present eight selection criteria (maintainability, trend, stability, portability, effect of other standard, constraint of the network, and applicability to the systems). We also applied some examples that several IT standards to our selection model for validating the model. We expect our model to help to decide objectively whether the new standard can be listed in DITA.

B-spline Curve Approximation Based on Adaptive Selection of Dominant Points (특징점들의 적응적 선택에 근거한 B-spline 곡선근사)

  • Lee J.H.;Park H.J.
    • Korean Journal of Computational Design and Engineering
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    • v.11 no.1
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    • pp.1-10
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    • 2006
  • This paper addresses B-spline curve approximation of a set of ordered points to a specified toterance. The important issue in this problem is to reduce the number of control points while keeping the desired accuracy in the resulting B-spline curve. In this paper we propose a new method for error-bounded B-spline curve approximation based on adaptive selection of dominant points. The method first selects from the given points initial dominant points that govern the overall shape of the point set. It then computes a knot vector using the dominant points and performs B-spline curve fitting to all the given points. If the fitted B-spline curve cannot approximate the points within the tolerance, the method selects more points as dominant points and repeats the curve fitting process. The knots are determined in each step by averaging the parameters of the dominant points. The resulting curve is a piecewise B-spline curve of order (degree+1) p with $C^{(p-2)}$ continuity at each knot. The shape index of a point set is introduced to facilitate the dominant point selection during the iterative curve fitting process. Compared with previous methods for error-bounded B-spline curve approximation, the proposed method requires much less control points to approximate the given point set with the desired shape fidelity. Some experimental results demonstrate its usefulness and quality.

Case Analyses of the Selection Process of an Excavation Method (지하공사 사례를 기반으로 한 터파기 공법 선정프로세스 분석)

  • Park, Sang-Hyun;Lee, Ghang;Choi, Myung-Seok;Kang, Hyun-Jeong;Rhim, Hong-Cheol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.04a
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    • pp.101-104
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    • 2007
  • As the proportion of underground construction increases, the impact of inappropriate selection of a underground construction method for a construction size increases. The purpose of this study is to develop an objective way of selecting an excavation method. There have been several attempts to achieve the same goal using various data mining methods such as the artificial neural network, the support vector machine, and the case-based reasoning. However, they focused only on the selection of a retaining wall construction method out of six types of retaining walls. When we categorized an underground construction work into four groups and added more number of independent variables (i.e., more number of construction methods), the predictability decreased. As an alternative, we developed a decision tree by analyzing 25 earthwork cases with detailed information. We implemented the developed decision tree as a computer-supported program called Dr. underground and are still in the process of validating and revising the decision tree. This study is still in a preliminary stage and will be improved by collecting and analyzing more cases.

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A STUDY ON THE IMPROVEMENT OF KAO STUDENT SELECTION AND EDUCATIONAL METHOD (한국천문올림피아드 학생선발 및 교육방법 개선을 위한 조사연구)

  • Yim, In Sung;Sung, Hyun-Il;Kim, Yoo Jea
    • Publications of The Korean Astronomical Society
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    • v.27 no.5
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    • pp.431-438
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    • 2012
  • A number of middle and high school students are selected at the Korea Astronomy Olympiad (KAO) in every year. In the first stage of the selection, the resume, school transcript, and recommendation letters from teachers are referred. In the second stage, after video lectures and weekend observation classes, students are tested with on-line homeworks, and interviewed through internet. For 118 students who have gone through the second stage of the 2012 KAO, we have conducted a questionnaire survey, which asks the students the motivation and preparation for the KAO. The survey has also included inquiries for the selection process and education program of the 2012 KAO; the replies will be used as feedbacks for the next year's KAO. The survey has revealed that the first stage worked well, while the second stage needs to be improved in terms of fairness and objectivity. We have found that most students received private tutorings for the KAO, so we suggest efforts should be made for students to be able to prepare the KAO without receiving private tutorings.

Adaptation for Object-based MPEG-4 Content with Multiple Streams (다중 스트림을 이용한 객체기반 MPEG-4 컨텐트의 적응 기법)

  • Cha Kyung-Ae
    • Journal of Korea Society of Industrial Information Systems
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    • v.11 no.3
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    • pp.69-81
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    • 2006
  • In this paper, an adaptive algorithm is proposed in streaming MPEG-4 contents with fluctuating resource amount such as throughput of network conditions. In the area of adaptive streaming issue, a lot of researches have been made on how to represent encoded media(such as video) bitstream in scalable way. By contrast, MPEG-4 supports object-based multimedia content which is composed of various types of media streams such as audio, video, image and other graphical elements. Thus, it can be more effective to provide individual media streams in scalable way for streaming object-based content to heterogeneous environment. The proposed method provides the multiple media streams corresponding to an object with different qualities and bit rate in order to support object based scalability to the MPEG-4 content. In addition, an optimal selection of the multiple streams for each object to meet a given constraint is proposed. The selection process is adopted a multiple choice knapsack problem with multi-step selection for the MPEG-4 objects with different scalability levels. The proposed algorithm enforces the optimal selection process to maintain the perceptual qualities of more important objects at the best effort. The experimental results show that the set of selected media stream for presenting objects meets a current transmission condition with more high perceptual quality.

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Case Study for Fingerprint ID Doorlock Design Development (지문인식도어락 디자인 개발 사례연구)

  • 서수웅
    • The Journal of the Korea Contents Association
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    • v.4 no.3
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    • pp.115-123
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    • 2004
  • This study suggests the output of the fingerprint doorlock design development through the structured methodology of concept selection in the process of design development, after characterizing the doorlock product itself. All of the early phases of product development are very important on eventual product success. Concept selection is the process of evaluating concepts with respect to customer needs and other criteria, comparing the relative strength and weaknesses of the concepts, and selecting one or more concepts for further investigation or development. To obtain the ideal concept o( new product, this work used a two-stage concept selection methodology which consist of concept screening and concept scoring. As a result, this study represents the fixed design rendering for mass production.

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Method for Selecting a Smart Television Product Model Using AHP (AHP를 이용한 스마트TV 제품모델 선정 방법)

  • Byun, Dae-Ho
    • Journal of Digital Convergence
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    • v.12 no.3
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    • pp.69-77
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    • 2014
  • Because smart televisions (TVs) have various and innovative functions that are different from traditional TVs, consumers are front with a complex decision-making problem when they want to buy a best TV among alternatives made by many TV makers. TV manufactures have developed and announced different types of smart TV models and they need a comparative study for evaluating their characteristics. In this paper, we suggest the Analytic Hierarchy Process(AHP) method for deciding the best smart TVs regarding many selection criteria. The method provides a decision support for consumers who like to purchase a smart TV. We describe criteria affecting the smart TV selection through a literature review and suggest a user testing method in order to derive accurate judgments from consumers. Using the Expert Choice software package, we show a an numerical example how the priority of smart TVs are computed.

A STUDY ON THE PROCESS OF LARGE-SCALE REPAIR OF A CONDOMINIUM

  • Seki, Eiji;Akiyama, Tetukazu
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2002.11a
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    • pp.295-300
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    • 2002
  • Since the contents of large-scale repair of a condominium were various, a plan document was not prepared. The owners association of the condominium has given priority to decision-making of price priority over quality. Examination is not performed about the contents of the construction supervision business, which checks whether suitable construction is performed, either. On the other hand, the know-how for builders, such as decision of the process plan under which the repair work lessens influence to the safety and life as much as possible since the place where the resident is living turns into a construction site, and selection of a method of construction, is just going to ask. It is an important subject how the structure of the construction contractor selection, which considered quality, is built. Then, this research focuses on large-scale repair construction of the condominium, and arranges the actual condition of a series of processes from plan document creation to construction supervision. The method of research collects the construction documents of the condominium that carried out Barge-scale repair construction. Next, collection arrangement of the data of construction builder selection is carried out. The method of the construction builder selection of those other than a construction price is examined. The method of quality control of large-scale repair construction is examined.

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A study on the effective operation&selection of the BTL project (BTL사업자의 효율적인 선정 및 운영에 관한 연구)

  • Kim, Kyung-Suk;Choi, Moon-Bok;Cho, Young-Ju
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2007.11a
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    • pp.599-602
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    • 2007
  • To enhance the competition of National power, the investment of SOC is an essential factor for infrastructure construction. The capital for SOC is so gigantic and the national finance is limited, engagement of various subject is necessary. So, Government is promoting the private sector to invest capital in SOC development. Nevertheless the increasement of SOC investment, various problems were issued in selection & operation of BTL. Therefore, to raise the probability of success for BTL project, escalation, unification and specialization of BTL affairs, BTL selection process were suggested in this study.

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