• Title/Summary/Keyword: probability theory

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A Path Specification Approach for Production Planning in Semiconductor Industry

  • Seo, Kwang-Kyu
    • Journal of the Semiconductor & Display Technology
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    • v.9 no.4
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    • pp.45-50
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    • 2010
  • This paper explores a new approach for modeling of decision-making problems that involve uncertain, time-dependent and sequence-dependent processes which can be applied to semiconductor industry. In the proposed approach, which is based on probability theory, approximate sample paths are required to be specified by probability and statistic characteristics. Completely specified sample paths are seen to be elementary and fundamental outcomes of the related experiment. The proposed approach is suitable for modeling real processes more accurately. A case study is applied to a single item production planning problem with continuous and uncertain demand and the solution obtained by the approximate path specification method shows less computational efforts and practically desirable features. The application possibility and general plan of the proposed approach in semiconductor manufacturing process is also described in the paper.

Probability distribution and statistical moments of the maximum wind velocity

  • Schettini, Evelia;Solari, Giovanni
    • Wind and Structures
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    • v.1 no.4
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    • pp.287-302
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    • 1998
  • This paper formulates a probabilistic model which is able to represent the maximum instantaneous wind velocity. Unlike the classical methods, where the randomness is circumscribed within the mean maximum component, this model relies also on the randomness of the maximum value of the turbulent fluctuation. The application of the FOSM method furnishes the first and second statistical moments in closed form. The comparison between the results herein obtained and those supplied by classical methods points out the central role of the turbulence intensity. Its importance is exalted when extending the analysis from the wind velocity to the wind pressure.

Fuzzy Relaxation Based on the Theory of Possibility and FAM

  • Uam, Tae-Uk;Park, Yang-Woo;Ha, Yeong-Ho
    • Journal of Electrical Engineering and information Science
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    • v.2 no.5
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    • pp.72-78
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    • 1997
  • This paper presents a fuzzy relaxation algorithm, which is based on the possibility and FAM instead of he probability and compatibility coefficients used in most of existing probabilistic relaxation algorithms, Because of eliminating stages for estimating of compatibility coefficients and normalization of the probability estimates, the proposed fuzzy relaxation algorithms increases the parallelism and has a simple iteration scheme. The construction of fuzzy relaxation scheme consists of the following three tasks: (1) definition of in/output linguistic variables, their term sets, and possibility. (2) Definition of FAM rule bases for relaxation using fuzzy compound relations. (3) Construction of the iteration scheme for calculating the new possibility estimate. Applications to region segmentation an ege detectiojn algorithms show that he proposed method can be used for not only reducing the image ambiguity and segmentation errors, but also enhancing the raw edge iteratively.

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Optimal Transmission Expansion Planning Considering the Uncertainties of Power Market (전력시장 불확실성을 고려한 최적 송전시스템 확장계획)

  • Son, Min-Kyun;Kim, Jin-O
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.4
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    • pp.560-566
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    • 2008
  • Today, as the power trades between generation companies and power customer are liberalized, the uncertainty level of operated power system is rapidly increased. Therefore, transmission operators as decision makers for transmission expansion are required to establish a deliberate investment plan for effective operations of transmission facilities considering forecasted conditions of power system. This paper proposes the methodology for the optimal solution of transmission expansion in deregulated power system. The paper obtains the expected value of transmission congestion cost for various scenarios by using occurrence probability. In addition, the paper assumes that increasing rates of loads are the probability distribution and indicates the location of expanded transmission line, the time for transmission expansion with the minimum cost for the future by performing the Montecarlo simulation. To minimize the investment risk as the variance of the congestion cost, Mean-Variance Markowitz portfolio theory is applied to the optimization model by the penalty factor of the variance. By the case study, the optimal solution for transmission expansion plan considering the feature of market participants is obtained.

Availability of the metapopulation theory in research of biological invasion: Focusing on the invasion success (침입생물 연구에 대한 메타개체군 이론의 활용 가능성: 침입 성공을 중심으로)

  • Jaejun Song;Jinsol Hong;Kijong Cho
    • Korean Journal of Environmental Biology
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    • v.40 no.4
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    • pp.525-549
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    • 2022
  • The process of biological invasion is led by the dynamics of a population as a demographic and evolutionary unit. Spatial structure can affect the population dynamics, and it is worth being considered in research on biological invasion which is always accompanied by dispersal. Metapopulation theory is a representative approach to spatially structured populations, which is chiefly applied in the field of ecology and evolutionary biology despite the controversy about its definition. In this study, metapopulation was considered as a spatially structured population that includes at least one subpopulation with significant extinction probability. The early phase of the invasion is suitable to be analyzed in aspects of the metapopulation concept because the introduced population usually has a high extinction probability, and their ecological·genetic traits determining the invasiveness can be affected by the metapopulation structure. Although it is important in the explanation of the prediction of the invasion probability, the metapopulation concept is rarely used in ecological research about biological invasion in Korea. It is expected that applying the metapopulation theory can supply a more detailed investigation of the invasion process at the population level, which is relatively inadequate in Korea. In this study, a framework dividing the invasive metapopulation into long- and middle-distance scales by the relative distance of movement to the natural dispersal range of species is proposed to easily analyze the effect of a metapopulation in real cases. Increased understanding of the mechanisms underlying invasions and improved prediction of future invasion risk are expected with the metapopulation concept and this framework.

A Case Study of Tunnel Keyblock Stability by the Block Failure Likelihood (블록파괴가능성을 이용한 터널키블록의 안정해석 사례연구)

  • 이인모;박준경;이석원
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.03a
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    • pp.315-322
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    • 1999
  • The probabilistic keyblock concept which was based upon block theory was applied to the example site by using the observed block moulds data. The more was the block failure likelihood (P(B)) which was defined by the product of the joint combination probability, the shape parameter and the instability parameter, the more were the frequencies of failures observed. If we can acquire these data during a tunnel construction stage, they will be used as a very useful data to construct another tunnel in the neighborhood. Furthermore, a sedimentary rock may have larger P(B) values than a crystalline rock, and for the given P(B) value, the percent block moulds are larger in the former than latter.

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Design-Parameter Computation of Subsurface Investigation Profile on Probability Method (확률론적 방법에 의한 지반조사 자료의 설계정수 산정)

  • 신은철;김종인;이준철
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.833-840
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    • 2003
  • The stability of structure, effectiveness of design and construction are very important factors in soil-structure design. The design-parameter is based on the test through laboratory-test and field-test. There are two ways to obtain the design-parameter. One is to through test, and the other is through relative documents and references. Recently, statistics has been used to get reliable data. In this study, Kriging method as Geostatistics and the theory of Bayesian's inference are used and the design-parameters are obtained. As the result of this study to the design-parameter is reliable and information about soil condition and soil properties in design and construction is easily found.

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Optimized Power Control for CDMA System under Fast Channel Variance (빠른 채널 변화를 수반하는 CDMA 환경에서의 최적 전력 제어)

  • Kim, Hyung-Suck;Byun, Ji-Young;You, Kwan-Ho
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.246-248
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    • 2004
  • In this paper, we propose an optimal power control algorithm for CDMA cellular systems. The proposed power control algorithm is based on linear quadratic control theory. As the cellular system includes the changeability of system environment or various noise, Kalman filter is adapted to estimate the time-varying interference. This is the well-known linear quadratic Gaussian (LQG) theory. Through this algorithm, power transmission of each mobile with optimal one is more realistic. Simulation results show a fast convergence rate to optimal power value, and a rapid decreasing outage probability.

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Development of New Management Prediction Support System based on Non-stochastic Model

  • Kaino, Toshihiro;Hirota, Kaoru;Mitsuta, Akimichi;Miura, Yasuyuki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.7-10
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    • 2003
  • In the field of financial technology, it is the U.S. initiative, and Japan is obliged to flattery in many respect. Currently Japan is in a too much defenseless situation that the economic structure is based on U.S. theory, In the conventional stochastic theory, it is also face that the prediction sometimes does not hit in the actual problem because it assumes a known probability distribution, none of which illustrates the real situation. A new research and development of management prediction support system is proposed based on fuzzy measures, that deals with the ambiguous, subjective evaluation by the people living in the real world well. Especially, the system will support venture, small and medium companies.

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A Research on Suggestion of Performance Grade for each Assessment Items of Self-Adhesive Waterproofing Sheet (자착식형 방수 시트의 평가 항목별 성능등급 제안에 관한 연구)

  • Park, Wan-Goo;An, Ki-Won;Heo, Neung-Hoe;Kim, Yun-Ho;Park, Jin-Samg;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.11a
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    • pp.23-25
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    • 2012
  • Because Self-Adhesive Waterproofing sheet has good constructability, it has been widely used. Also Self-Adhesive Waterproofing sheet is researched based on variety of materials and various of forms. However, producers have recognized about only pass KS quality standard. So, Self-Adhesive waterproofing sheet has been limited about improvement of performance. Therefore, in this research, proposed guideline of Self-Adhesive Waterproofing sheet for disinterested performance grade using probability theory and quality management theory.

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