• Title/Summary/Keyword: uncertain data

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Discovering classification knowledge using Rough Set and Granular Computing (러프집합과 Granular Computing을 이용한 분류지식 발견)

  • Choi, Sang-Chul;Lee, Chul-Heui
    • Proceedings of the KIEE Conference
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    • 2000.11d
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    • pp.672-674
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    • 2000
  • There are various ways in classification methodologies of data mining such as neural networks but the result should be explicit and understandable and the classification rules be short and clear. Rough set theory is a effective technique in extracting knowledge from incomplete and inconsistent information and makes an offer classification and approximation by various attributes with effect. This paper discusses granularity of knowledge for reasoning of uncertain concepts by using generalized rough set approximations based on hierarchical granulation structure and uses hierarchical classification methodology that is more effective technique for classification by applying core to upper level. The consistency rules with minimal attributes is discovered and applied to classifying real data.

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Applications of Soft Computing Techniques in Response Surface Based Approximate Optimization

  • Lee, Jongsoo;Kim, Seungjin
    • Journal of Mechanical Science and Technology
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    • v.15 no.8
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    • pp.1132-1142
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    • 2001
  • The paper describes the construction of global function approximation models for use in design optimization via global search techniques such as genetic algorithms. Two different approximation methods referred to as evolutionary fuzzy modeling (EFM) and neuro-fuzzy modeling (NFM) are implemented in the context of global approximate optimization. EFM and NFM are based on soft computing paradigms utilizing fuzzy systems, neural networks and evolutionary computing techniques. Such approximation methods may have their promising characteristics in a case where the training data is not sufficiently provided or uncertain information may be included in design process. Fuzzy inference system is the central system for of identifying the input/output relationship in both methods. The paper introduces the general procedures including fuzzy rule generation, membership function selection and inference process for EFM and NFM, and presents their generalization capabilities in terms of a number of fuzzy rules and training data with application to a three-bar truss optimization.

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A Probabilistic Reasoning in Incomplete Knowledge for Theorem Proving (불완전한 지식에서 정리증명을 위한 확률추론)

  • Kim, Jin-Sang;Shin, Yang-Kyu
    • Journal of the Korean Data and Information Science Society
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    • v.12 no.1
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    • pp.61-69
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    • 2001
  • We present a probabilistic reasoning method for inferring knowledge about mathematical truth before an automated theorem prover completes a proof. We use a Bayesian analysis to update beleif in truth, given theorem-proving progress, and show how decision-theoretic methods can be used to determine the value of continuing to deliberate versus taking immediate action in time-critical situations.

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Environmental Perception Considering Beam Opening Angle and Specular Reflection of Ultrasonic Sensors (초음파센서의 지향성 및 경면반사현상을 고려한 환경인식)

  • Ha, Yun-Su;Kim, Duck-Gon
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.8
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    • pp.919-926
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    • 2006
  • To move in unknown or uncertain environment, a mobile robot must collect informations from various sensors and use it to construct a representation of the external world. Ultrasonic sensor can provide range data for this purpose in a simple cost-effective way. However conventional ultrasonic sensor system for a mobile robot are not sufficient for environment recognition because of their large beam opening angle, specular reflection. This paper describe on environmental perception algorithm which can solve these problems in case using ultrasonic sensor. The algorithm consist of two parts. One is to solve beam opening angle problem by fusion from multiple ultrasonic sensors. The other is to cope with specular reflection problem in wall line extract, which is based on Hough Transform. Experiments to verify the validity of the proposed algorithm are carried out, and the results are provided at last part in this paper.

Application of Fuzzy Logic for Grinding Conditions

  • Kim Gun-hoi
    • International Journal of Precision Engineering and Manufacturing
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    • v.6 no.2
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    • pp.40-45
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    • 2005
  • This paper has presented an application of an optimum grinding conditions based on the fuzzy logic. Fuzzy logic can handle vague and uncertain knowledge, and presents a scheme for integrating data with various kinds of grinding data. Especially, this research is capable of determining the grinding conditions taking into account some fuzzy membership function represented for trapezoidal form such as hardness and surface roughness of workpiece, material tensile strength and elongation, and requirement of grinding method. Larsen's fuzzy production method utilizing the fuzzy production rule can be applied on the establishment of grinding conditions, and also the output value obtained by the center of gravity method can effectively utilize the optimum grinding conditions.

A Study on the Multi-Attribute Decision Making based on Eigenvector (Eigenvector를 이용한 다속성의사결정에 관한 연구)

  • 안동규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.18 no.34
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    • pp.1-8
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    • 1995
  • The practical problem of multi-attribute decision making are formed by the uncertain attribute that the attribute by the alternatives cannot be defined or judged crisphy but only as vague. In this case the final judgements are also represented by vague which have to be ordered to determine the optimal alternative. The problem is more complex if the evaluations of alternatives according to each attribute are expresed vague. This paper described the results of a study done to determine how well multi-attribute decision marking perform in helping a decision maker arrive at a preferred solution to a multi-attribute problem with vague attribute. Particular area of research has concentrated on the issue of combining quantitative and qualitative data supplied by estimation. Futher study considers some method for suitable evaluation of qualitative data.

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Consumption Value according to College Students' Self-Efficacy Typology (대학생의 자기효능감 유형에 따른 소비가치)

  • Park, Eun-Hee;Ku, Yang-Suk
    • Korean Journal of Human Ecology
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    • v.17 no.5
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    • pp.927-938
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    • 2008
  • The purpose of this study was to classify self-efficacy typology and analyze the relationship between self-efficacy and consumption value of college students as consumers. Data were gathered by surveying college students living in Daegu and Kyungbook area using convenient sampling. 513 questionnaires were used in the statistical analysis. Data were analyzed by frequency, factor analysis, cluster analysis, correlation analysis, ANOVA, and Duncan-test. The findings are as follows. The self-efficacy typologies of college students were classified into three groups such as challenging confident accomplish oriented, stable uncertain accomplish oriented, and stable accomplish oriented. In the relationship of the self-efficacy was related to the sub-variables of consumption value. The self-efficacy oriented group showed different all the sub-variables of consumption value factors.

An Examination of Sediment Discharge Computation Errors Related to Imprecise Factors (부정확한 인자와 관계된 유사량 산정 오류에 대한 검증)

  • 정관수
    • Water for future
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    • v.29 no.3
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    • pp.129-142
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    • 1996
  • This study investigates the magnitude of errors that can be expected in integrating sediment concentration in a vertical, basede on a single-point measurement, because of errors in input data. Potential error sources, including sampler location, water surface elevation, bed elevation, fall velocity, $\beta$ value, and $\kappa$ value were comparatively examined using data from a special study on the Rio Grande Conveyance channel in New Mexico. It is concluded that simple forms of equations for the vertical distribution of velocity and sediment concentration based on a single-point field sample of suspended sediment. The most uncertain point in the computation is related to the Rouse number z in the equation for the vertical concentration distribution of suspended sediment.

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Seven Facets of Learning Agility in Higher Education for Future Society

  • SUNG, Eunmo
    • Educational Technology International
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    • v.22 no.2
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    • pp.169-197
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    • 2021
  • Learning agility as high potentials is drawing attention as a competency for leading an uncertain future society. The present study aims to determine the factors of learning agility in higher education context for future society. To address this goal, Major factors related to learning agility were derived through literature review and statistically verified. For statistical analysis, the nationwide data were collected from 1,000 undergraduate students in South Korea by National Youth Policy Institute. The participants asked to answer 29 items of learning agility questionnaires (LAQ). The collected data were analyzed by descriptive statistical analysis, exploratory factor analysis, and confirmatory factor analysis. As a result, learning agility items were verified normality and reliability. Learning agility was identified seven factors; challenging mind, learning responsibility, reflecting experience, intellectual curiosity, systemic thinking, change adaptability, and logical thinking. Also, the structural model fit of the seven factors of learning agility was also confirmed to be good. Based on the findings of the present study, empirical, theoretical, and practical contributions were presented, and suggestions for further research were proposed in detail.

A Study on the Algorithms of One-way Transmission for Stable Data Sharing (안정적인 데이터 공유를 위한 일방향 전송 알고리즘에 대한 연구)

  • Kang, Min Kyung;Koh, Keun Ho;Ahn, Seong Jin
    • Convergence Security Journal
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    • v.16 no.7
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    • pp.61-68
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    • 2016
  • As many high-tech researches are shown in various field by sharing data via computer network, a necessity for stable data-sharing environment has suggested steadily. This research covers one-way communication protocol which is newly developed through the necessity. In this protocol, data is transmitted only in one way. One-way transmission has strong possibility to protect system from uncertain and potential risk, but it is impossible to receive ACK(Acknowledge Character) packet about data. Therefore, we need to find a way which duplex protocol such as TCP, ICMP works properly and practical communication falls under one-way transmission environment. To conclude, we analysed possible scenario in each protocol from three layers - interface layer, internet layer and transmission layer and approached how to resolve the problem in each way.