• Title/Summary/Keyword: Optimum selection probability

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Optimum Design of Structural Monitoring System using Artificial Neural Network and Multilevel Sensitivity Analysis (다단계민감도 분석 및 인공신경망을 이용한 최적 계측시스템 선정기법)

  • 김상효;김병진
    • Computational Structural Engineering
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    • v.10 no.4
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    • pp.303-313
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    • 1997
  • Though many techniques for the damage assessment of structures have been studied recently, most of them can be only applied to simple structures. Therefore, practical damage assessment techniques that evaluate the damage location and the damage state for large structures need to be developed. In this study, a damage assessment technique using a neural network is developed, in which the bilevel damage assessment procedure is proposed to evaluate the damage of a large structure from the limited monitoring data. The procedure is as follows ; first, for the rational selection of damage critical members, the members that affect the probability of failure or unusual structural behavior are selected by sensitivity analysis. Secondly, the monitoring points and the number of sensors that are sensitive to the damage severity of the selected members are also selected through the sensitivity analysis with a proposed sensitivity measurement format. The validity and applicability of the developed technique are demonstrated by various examples, and it has been shown that the practical information on the damage state of the selected critical members can be assessed even though the limited monitoring data have been used.

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A Study on Commercial Power of Traditional Market

  • Baik, Key-Young;Youn, Myoung-Kil
    • East Asian Journal of Business Economics (EAJBE)
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    • v.4 no.2
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    • pp.1-11
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    • 2016
  • This study investigated commercial power theory of traditional market through the analysis of literature review. Consumers' store selection models are made up a theory based on normative hypothesis, theory of mutual reaction, utility function estimation model, and cognitive-behavioral model. Detailed models are as follows. Normative hypothesis based theory is divided into Reilly's retail gratification theory and Converse's revised retail g ratification theory. Interaction theory is composed of Huff's probability gratification theory, MCI model and Multi-nominal Logit Model (MNL model). There are four models in retail organization position theory such as central place theories, single store position theory, multi store position - assign model, and retail growth potential model. In case of single store position theory, theoretical and empirical techniques have developed for a decision to optimum single store position. Those are like these, a check list, the most simple and systematic method, analogy, and microanalysis technique. Aforementioned models are theoretical and mathematical commercial power measurement and/or model. The study has rather limitations because the variation factors included in formula are only a part of actual commercial power. Therefore, further study shall be made continuously to commercial power areas and variables.

A Study on the Selection of Optimum Probability Distribution for Rainfall Frequency Analysis (강우빈도해석 시 최적분포형 선정에 관한 연구)

  • Choi, Hong-Geun;Kim, Jin-Young;Kwon, Young-Jun;Kwon, Hyun-Han
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.412-412
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    • 2017
  • 강우빈도해석을 위해서는 확률분포선정이 우선적으로 이루어져야 한다. 우리나라에서는 사용상의 편리상, 기존 해석결과와의 연속성 등을 이유로 Gumbel 확률분포가 가장 일반적으로 활용되고 있다. 그러나, 분포형 선정에 따른 확률강수량의 차이가 크게 발생한다는 점에서 단순히 해석상의 편리성을 기준으로 분포형 선정이 이루어지는 것은 바람직하지 않다. 특히, 우리나라에서 강우빈도해석 시 분포형 선정은 형식적인 수준에 그치고 있으며, 주로 KS검정, 검정 등 적합도 검정을 통해 고려된 분포형의 통계적 유의성만을 평가하고 있다. 그러나, 최적 분포형 선정이라는 관점에서 이러한 유의성 검정보다는 정량적인 지표를 기준으로 확률분포형 선정이 이루어지는 것이 적합할 것으로 판단된다. 즉, 자료의 설명력이 가장 우수한 분포를 정량적 지표를 기준으로 추정하는 것이 수문통계학적으로 적합성을 갖는다. 이러한 점에서 본 연구에서는 우도함수, BIC 및 AIC를 기준으로 우리나라 주요 강수지점에서 대해서 최적 분포형을 선정하고, 기존 Gumbel 분포를 기준으로 산정된 확률강수량과의 양적차이를 평가해보고자 한다.

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Extraction of Corresponding Points Using EMSAC Algorithm (EMSAC 알고리듬을 이용한 대응점 추출에 관한 연구)

  • Ye, Soo-Young;Jeon, Ah-Young;Jeon, Gye-Rok;Nam, Ki-Gon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.4 s.316
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    • pp.44-50
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    • 2007
  • In this paper, we proposed the algorithm for the extraction of the corresponding points from images. The proposed algorithm EMSAC is based on RANSAC and EM algorithms. In the RANSAC procedure, the N corresponding points are randomly selected from the observed total corresponding points to estimate the homography matrix, H. This procedure continues on its repetition until the optimum H are estimated within number of repetition maximum. Therefore, it takes much time and does not converge sometimes. To overcome the drawbacks, the EM algorithm was used for the selection of N corresponding points. The EM algorithm extracts the corresponding points with the highest probability density to estimate the optimum H. By the experiments, it is demonstrated that the proposed method has exact and fast performance on extraction of corresponding points by combining RANSAC with EM.

Optimum design and vibration control of a space structure with the hybrid semi-active control devices

  • Zhan, Meng;Wang, Sheliang;Yang, Tao;Liu, Yang;Yu, Binshan
    • Smart Structures and Systems
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    • v.19 no.4
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    • pp.341-350
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    • 2017
  • Based on the super elastic properties of the shape memory alloy (SMA) and the inverse piezoelectric effect of piezoelectric (PZT) ceramics, a kind of hybrid semi-active control device was designed and made, its mechanical properties test was done under different frequency and different voltage. The local search ability of genetic algorithm is poor, which would fall into the defect of prematurity easily. A kind of adaptive immune memory cloning algorithm(AIMCA) was proposed based on the simulation of clone selection and immune memory process. It can adjust the mutation probability and clone scale adaptively through the way of introducing memory cell and antibody incentive degrees. And performance indicator based on the modal controllable degree was taken as antigen-antibody affinity function, the optimization analysis of damper layout in a space truss structure was done. The structural seismic response was analyzed by applying the neural network prediction model and T-S fuzzy logic. Results show that SMA and PZT friction composite damper has a good energy dissipation capacity and stable performance, the bigger voltage, the better energy dissipation ability. Compared with genetic algorithm, the adaptive immune memory clone algorithm overcomes the problem of prematurity effectively. Besides, it has stronger global searching ability, better population diversity and faster convergence speed, makes the damper has a better arrangement position in structural dampers optimization leading to the better damping effect.

Impact of Marketing Losses on Efficiency in Transacting Banana in Scarce Rainfall Zone of Andhra Pradesh, India

  • Kumar, K. Nirmal Ravi
    • Agribusiness and Information Management
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    • v.9 no.2
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    • pp.1-11
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    • 2017
  • Introduction: To analyze the impact of marketing losses on efficiency in transacting banana in Kurnool district of SRZ in Andhra Pradesh and to assess the opinions of the farmers on the constraints in transacting banana. Research back ground, Materials and Methods: The study relies exclusively on primary information obtained from the banana farmers of Kurnool District. Purposive sampling procedure was followed for the selection of the study area. Top two mandals in the district and top two villages in each mandal are selected in accordance with the area under cultivation of banana. Probability proportion to size was followed regarding the selection of sample farmers and accordingly 60 marginal, 37 small and 23 other farmers were selected and thereby, the total sample size was 120. Result and Discussion: Three marketing channels were identified in the marketing of banana in Kurnool district viz., Producer ${\rightarrow}$ Local-exporter ${\rightarrow}$ Wholesaler ${\rightarrow}$ Retailer ${\rightarrow}$ Consumer (Channel-I), Producer ${\rightarrow}$ Wholesaler ${\rightarrow}$ Cart-vendor ${\rightarrow}$ Consumer (Channel-II) and Producer ${\rightarrow}$ Juice-holder ${\rightarrow}$ Consumer (Channel-III). With the inclusion of marketing losses in the price spread analysis of banana in all the three channels, the marketing costs of all the intermediaries were increased and thereby, the farmer's share in consumer's rupee and Net Marketing Margins of the agencies are on the decline. So, without inclusion of marketing losses, the farmer's share in consumer's rupee and Net Marketing Margins of all the agencies are overvalued. The higher the marketing losses, the more is the negative impact on farmer's net selling price, net marketing margins of the intermediaries and marketing efficiency. The sample farmers are facing major problems in marketing of banana like frequent price fluctuations, unorganized marketing and lack of transportation facilities on priority basis. Suggestions: It is suggested to educate the farmers regarding the optimum maturity index for harvest, use of mechanical harvesters, proper placement of fruits during storage and ripening, better packaging and cushioning technologies to absorb shocks during transportation, strengthening of storage facilities and transport facilities, encourage co-operative marketing etc., to promote marketing efficiency of banana in the study area.