• Title/Summary/Keyword: Shannon Function

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Reduction of Air-pumping Noise based on a Genetic Algorithm (유전자 알고리즘을 이용한 타이어 공력소음의 저감)

  • Kim, Eui-Youl;Hwang, Sung-Wook;Kim, Byung-Hyun;Lee, Sang-Kwon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.1
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    • pp.61-73
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    • 2012
  • The paper presents the novel approach to solve some problems occurred in application of the genetic algorithm to the determination of the optimal tire pattern sequence in order to reduce the tire air-pumping noise which is generated by the repeated compression and expansion of the air cavity between tire pattern and road surface. The genetic algorithm has been used to find the optimal tire pattern sequence having a low level of tire air-pumping noise using the image based air-pumping model. In the genetic algorithm used in the previous researches, there are some problems in the encoding structure and the selection of objective function. The paper proposed single encoding element with five integers, divergent objective function based on evolutionary process and the optimal evolutionary rate based on Shannon entropy to solve the problems. The results of the proposed genetic algorithm with evolutionary process are compared with those of the randomized algorithm without evolutionary process on the two-dimensional normal distribution. It is confirmed that the genetic algorithm is more effective to reduce the peak value of the predicted tire air-pumping noise and the consistency and cohesion of the obtained simulation results are also improved in terms of probability.

Status, Distribution, Conservation and Use Value of Medicinal and Aromatic Plants (MAPs) in Sagarmatha National Park, Nepal

  • Gaire, Damodar
    • Journal of Forest and Environmental Science
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    • v.30 no.3
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    • pp.253-258
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    • 2014
  • The study attempts to assess the status, distribution, conservation and use value of Medicinal and Aromatic Plant (MAPs) in the Sagarmatha National Park. Altogether 62 species of MAPs belonging to 47 genera and 33 families have been recorded in the study area. 10 species, belonging to 9 families are categorized as the potential species. Out of the these species, most potential in local but threatened species are Allium hypsistum Stearn, Cordyceps sinensis Sacc, Dactylorhiza hatagirea Soo, Nardostachys grandiflora DC, Aconitum orochryseum, Ephedra gerardiana Wall. Ex. Stapf, Swertia multicaulis D. Don, Picrorhiza scrophulariflora Penne, Rheum australe. D. Don, Malva verticillataL and Swertia pedicallata Benerji. By analysis of data using Simpson's diversity index (SI) and Shannon weaver function (H'), there was high diversity (more heterogeneous) MAPs species composition in the Manjo Gate to Large Dobhan. (0.98349). Less diversity (less heterogeneous) MAPs species composition was in Tyanboche to Pangoche (0.90419). Similarly, the Shannon weaver function shows that in plots laying out in Mongla to Phorche are evenly distributed than others However, higher MAPs species (i.e., 31) was found in the way of Manjo Gate to Larja Dobhan than others.

MODEL BASED DIAGNOSTICS FOR A GEARBOX USING INFORMATION THEORY

  • Choi, J.;Bryant, M.D.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.459-460
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    • 2002
  • This article discusses a diagnostics method based on models, and information theory. From an extensive system dynamics bond graph model of a gearbox [1], simulated were various cases germane to this diagnostics approach, including the response of an ideal gearbox, which functions perfectly to designer's specifications, and degraded gearboxes with tooth root cracking. By comparing these cases and constructing a signal flow analogy between the gearbox and a communication channel, Shannon' s information theory [2], including theorems, was applied to the gearbox to assess system health, in terms of ability to function.

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A Fast Method for Finding the Optimal Threshold for Image Segmentation (영상분할의 최적 임계치를 구하는 빠른 방법)

  • 신용식;이정훈
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.109-112
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    • 2001
  • 영상분할에 있어서 최적의 임계치를 구하는 것은 영상을 구성하고 있는 픽셀들을 의미있는 집단으로 나누는 거와 같으며 이를 위하여 퍼지화 정도를 측정하여 최소의 퍼지화 정도를 갖는 임계치를 최적의 임계치로 설정한다. 일반적으로 소속도는 하나의 픽셀과 그 픽셀이 속한 영역의 관계로 표현될 수 있는데 소속도 계산을 위한 엔트로피로 샤논(Shannon)함수를 사용한다[1]. Liang-Kai Huang에 의하여 제안된 알고리즘은 그 수렴속도 면에 있어서 많은 문제점을 갖고 있다[2]. 본 논문에서는 이런 수렴속도를 좀더 개선하기 위하여 SPOI(Simplified Fixed Point Iteration)를 제안하고 여러 가지 실험영상을 사용하여 졔안된 논문의 우수성을 보이고자 한다. 실험결과 적절한 임계치를 구하면서도 기존의 논문보다 속도면에서 상당히 우수한 특성을 보이고 있다.

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The Exponentiated Weibull-Geometric Distribution: Properties and Estimations

  • Chung, Younshik;Kang, Yongbeen
    • Communications for Statistical Applications and Methods
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    • v.21 no.2
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    • pp.147-160
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    • 2014
  • In this paper, we introduce the exponentiated Weibull-geometric (EWG) distribution which generalizes two-parameter exponentiated Weibull (EW) distribution introduced by Mudholkar et al. (1995). This proposed distribution is obtained by compounding the exponentiated Weibull with geometric distribution. We derive its cumulative distribution function (CDF), hazard function and the density of the order statistics and calculate expressions for its moments and the moments of the order statistics. The hazard function of the EWG distribution can be decreasing, increasing or bathtub-shaped among others. Also, we give expressions for the Renyi and Shannon entropies. The maximum likelihood estimation is obtained by using EM-algorithm (Dempster et al., 1977; McLachlan and Krishnan, 1997). We can obtain the Bayesian estimation by using Gibbs sampler with Metropolis-Hastings algorithm. Also, we give application with real data set to show the flexibility of the EWG distribution. Finally, summary and discussion are mentioned.

Decision of the Node Decomposition Type for the Minimization of OPKFDDs (OPKFDD 최소화를 위한 노드의 확장형 결정)

  • Jung, Mi-Gyoung;Hwang, Min;Lee, Guee-Sang;Kim, Young-Chul
    • The KIPS Transactions:PartA
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    • v.9A no.3
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    • pp.363-370
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    • 2002
  • OPKFDD (Ordered Pseudo-Kronecker Functional Decision Diagram) is one of ordered-DDs (Decision Diagrams) in which each node can take one of three decomposition types : Shannon, positive Davio and negative Davio decompositions. Whereas OBDD (Ordered Binary Decision Diagram) uses only the Shannon decomposition in each node, OPKFDD uses the three decompositions and generates representations of functions with smaller number of nodes than other DDs. However, this leads to the extreme difficulty of getting an optimal solution for the minimization of OPKFDD. Since an appropriate decomposition type has to be chosen for each node, the size of the representation is decided by the selection of the decomposition type. We propose a heuristic method to generate OPKFDD efficiently from the OBDD of the given function and the algorithm of the decision of decomposition type for a given variable ordering. Experimental results demonstrate the performance of the algorithm.

Chaotic Time Series Prediction using Extended Fuzzy Entropy Clustering (확장된 퍼지엔트로피 클러스터링을 이용한 카오스 시계열 데이터 예측)

  • 박인규
    • Proceedings of the IEEK Conference
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    • 2000.06c
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    • pp.5-8
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    • 2000
  • In this paper, we propose new algorithms for the partition of input space and the generation of fuzzy control rules. The one consists of Shannon and extended fuzzy entropy function, the other consists of adaptive fuzzy neural system with back propagation teaming rule. The focus of this scheme is to realize the optimal fuzzy rule base with the minimal number of the parameters of the rules, reducing the complexity of the system. The proposed algorithm is tested with the time series prediction problem using Mackey-Glass chaotic time series.

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A REFINEMENT OF THE JENSEN-SIMIC-MERCER INEQUALITY WITH APPLICATIONS TO ENTROPY

  • Sayyari, Yamin
    • The Pure and Applied Mathematics
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    • v.29 no.1
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    • pp.51-57
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    • 2022
  • The Jensen, Simic and Mercer inequalities are very important inequalities in theory of inequalities and some results are devoted to this inequalities. In this paper, firstly, we establish extension of Jensen-Simic-Mercer inequality. After that, we investigate bounds for Shannons entropy of a probability distribution. Finally, We give some new applications in analysis.

A phase synthesis time reversal impact imaging method for on-line composite structure monitoring

  • Qiu, Lei;Yuan, Shenfang
    • Smart Structures and Systems
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    • v.8 no.3
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    • pp.303-320
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    • 2011
  • Comparing to active damage monitoring, impact localization on composite by using time reversal focusing method has several difficulties. First, the transfer function of the actuator-sensor path is difficult to be obtained because of the limitation that no impact experiment is permitted to perform on the real structure and the difficulty to model it because the performance of real aircraft composite is much more complicated comparing to metal structure. Second, the position of impact is unknown and can not be controlled as the excitation signal used in the active monitoring. This makes it not applicable to compare the difference between the excitation and the focused signal. Another difficulty is that impact signal is frequency broadband, giving rise to the difficulty to process virtual synthesis because of the highly dispersion nature of frequency broadband Lamb wave in plate-like structure. Aiming at developing a practical method for on-line localization of impact on aircraft composite structure which can take advantage of time reversal focusing and does not rely on the transfer function, a PZT sensor array based phase synthesis time reversal impact imaging method is proposed. The complex Shannon wavelet transform is presented to extract the frequency narrow-band signals from the impact responded signals of PZT sensors. A phase synthesis process of the frequency narrow-band signals is implemented to search the time reversal focusing position on the structure which represents the impact position. Evaluation experiments on a carbon fiber composite structure show that the proposed method realizes the impact imaging and localization with an error less than 1.5 cm. Discussion of the influence of velocity errors and measurement noise is also given in detail.

An efficient algorithm for the design of combinational circuits with low power consumption (저전력 소모 조합 회로의 설계를 위한 효율적인 알고리듬)

  • Kim, Hyoung;Choi, Ick-Sung;Seo, Dong-Wook;Heo, Hun;Hwang, Sun-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.5
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    • pp.1221-1229
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    • 1996
  • This paper proposes a heuristic algorithm for low power implementation of combinational circuits. Selecting an input variable for a given function, the proposed algorithm performs Shannon exansion with respect to the variable to reduce the number of gates in the subcircuit realizing the coffactor function, reducting the power dissipation of the implemented circuit. experimental results for the MCNC benchmarks show that the proposed algorithm is effective by generating the circuits consuming the power 48.9% less on the average, when compared to the previous algorithm based on precomputation logic.

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