• Title/Summary/Keyword: improved method

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개선된 미분 진화 알고리즘에 의한 퍼지 모델의 설계 (Design of Fuzzy Models with the Aid of an Improved Differential Evolution)

  • 김현기;오성권
    • 한국지능시스템학회논문지
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    • 제22권4호
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    • pp.399-404
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    • 2012
  • Evolutionary algorithms such as genetic algorithm (GA) have been proven their effectiveness when applying to the design of fuzzy models. However, it tends to suffer from computationally expensWive due to the slow convergence speed. In this study, we propose an approach to develop fuzzy models by means of an improved differential evolution (IDE) to overcome this limitation. The improved differential evolution (IDE) is realized by means of an orthogonal approach and differential evolution. With the invoking orthogonal method, the IDE can search the solution space more efficiently. In the design of fuzzy models, we concern two mechanisms, namely structure identification and parameter estimation. The structure identification is supported by the IDE and C-Means while the parameter estimation is realized via IDE and a standard least square error method. Experimental studies demonstrate that the proposed model leads to improved performance. The proposed model is also contrasted with the quality of some fuzzy models already reported in the literature.

Kano 품질속성 평가방법론들의 실증적 비교분석 (An Empirical Comparative Analysis Between Kano and Improved Kano Methods)

  • 윤재욱;이희영
    • 품질경영학회지
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    • 제37권4호
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    • pp.31-42
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    • 2009
  • Various studies have been undertaken in order to effectively understand customer requirements. Kano proposed a dualistic approach, physical fulfillment and customer satisfaction, to differentiate Attractive, Must-be, One-dimensional quality attributes. As there were a few limitations on the Kano's method, researchers have proposed improved methods. However, there have been few empirical evidences that the improved methods are superior to the original Kano's method for identifying relevant quality attributes. The objective of this study is to provide a comparative study on Kano and improved Kanomethods based on empirical analysis of quality attributes on University services. For the analysis of the questionnaire formats, the Kano's original 5 scale questionnaire is more effective than improved methods, direct and 3 scale questionnaire. For the analysis of evaluation methods, the original Kano and Timko's method using the evaluation table are more effective than quantifying methods, Domouchel and Lim's methods.

개선된 PO 방법을 이용한 태양광 발전의 MPPT 제어 (MPPT Control of PV System using Improved PO Method)

  • 고재섭;정동화
    • 전기학회논문지
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    • 제63권12호
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    • pp.1649-1654
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    • 2014
  • This paper proposes the method which is improved a performance of PO MPPT control in PV system. The PO method is continually changed voltage toward direction that increases power, and if output power is decreased by changing voltage, a power of the conventional PO method is changed to a power before one step. These operations causes reduce of MPPT performance. Therefore, this paper proposes the MPPT method that can be improved the performance of the conventional PO method. When voltage is changed to direction of reducing power, the method proposed in this paper is changed to the voltage the opposite direction of twice step size. The MPPT performance of proposed method in this paper is compared with conventional PO method and proved the validity of this paper using these results.

An Improved Method of Pore Size Distribution Analysis

  • Cho, Hyun-Woo;Ahn, Woon-Sun;Halsey, G. D.
    • Bulletin of the Korean Chemical Society
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    • 제9권2호
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    • pp.94-98
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    • 1988
  • An improvement over the method of pore size distribution analysis has been made in this work. The improved method is based upon the idea of the micro pore analysis of Mikhail, Brunauer, and Bodor, and utilizes the V-t curve of nitrogen adsorption. Two pore models are assumed, and the deviation of the initial slope of the V-t plot is ascribed to the pore filling and to the adsorption on the wall of unfilled pores. The improved method of this work is very convenient in that the analysis starts from the small pore regions. The method of this work is however quite distinct from the similar V-t plot method proposed by Sellevold and Radjy. The proposed method is applied to a few adsorbents, and very satisfactory results are obtained. The cumulative surface area calculated by this method also agrees very well with those obtained by the BET plot or by the t-method.

A New Method for Robust and Secure Image Hash Improved FJLT

  • ;김형중
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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    • pp.143-146
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    • 2009
  • There are some image hash methods, in the paper four image hash methods have been compared: FJLT (Fast Johnson- Lindenstrauss Transform), SVD (Singular Value Decomposition), NMF (Non-Negative Matrix Factorization), FP (Feature Point). From the compared result, FJLT method can't be used in the online. the search time is very slow because of the KNN algorithm. So FJLT method has been improved in the paper.

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옵티컬 플로우를 이용한 논리연산 트래킹과 그레디언트 연산속도 개선 (Logical operation tracking using optical flow and improvement of gradient operation speed)

  • 안태홍;정상화;박종안
    • 한국통신학회논문지
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    • 제23권4호
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    • pp.787-795
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    • 1998
  • 본 논문에서는 이동물체의 움직임 추정을 위한 옵티컬 플로우(Optical Flow: OF)의 계산에 필요한 그레디언트(Gradient)의 연산 속도를 개선하고. OF와 에지의 논리연산에 의하여 이동물체의 움직임 정계를 추정할 수 있으며 잡음이 있는 영상에서도 이동물체를 추정할 수 있는 방법을 제안한다. 이것은 저레벨에서 OF와 에지를 논리 연산하므로써 불확실한 배경에서 이동물체를 식별하고 물체를 추적하는 방법으로 기존의 이동물체 추정 알고리즘을 간소화시킨 것이다. 또한, 그레디언트 연산속도를 개선한 본 논문의 방법 I과 방법 II를 이용하여 그레이레 벨값의 변화가 있는 영상에 대하여 시뮬레이션을 행하였다. 그레디언트 연산에 걸리는 전체적인 시간을 평균한 결과 방법 I 은 기존의 방법보다 12% 연산속도가 개선되었고, 방법 II는 37% 연산속도가 개선되었다.

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OBSERVATIONS ON A FURTHER IMPROVED ($\frac{G}{G}$) - EXPANSION METHOD AND THE EXTENDED TANH-METHOD FOR FINDING EXACT SOLUTIONS OF NONLINEAR PDES

  • Zayed, E.M.E.
    • Journal of applied mathematics & informatics
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    • 제30권1_2호
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    • pp.253-264
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    • 2012
  • In the present article, we construct the exact traveling wave solutions of nonlinear PDEs in the mathematical physics via the (1+1)-dimensional Boussinesq equation by using the following two methods: (i) A further improved ($\frac{G}{G}$) - expansion method, where $G=G({\xi})$ satisfies the auxiliary ordinary differential equation $[G^{\prime}({\xi})]^2=aG^2({\xi})+bG^4({\xi})+cG^6({\xi})$, where ${\xi}=x-Vt$ while $a$, $b$, $c$ and $V$ are constants. (ii) The well known extended tanh-function method. We show that some of the exact solutions obtained by these two methods are equivalent. Note that the first method (i) has not been used by anyone before which gives more exact solutions than the second method (ii).

Anomaly detection of isolating switch based on single shot multibox detector and improved frame differencing

  • Duan, Yuanfeng;Zhu, Qi;Zhang, Hongmei;Wei, Wei;Yun, Chung Bang
    • Smart Structures and Systems
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    • 제28권6호
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    • pp.811-825
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    • 2021
  • High-voltage isolating switches play a paramount role in ensuring the safety of power supply systems. However, their exposure to outdoor environmental conditions may cause serious physical defects, which may result in great risk to power supply systems and society. Image processing-based methods have been used for anomaly detection. However, their accuracy is affected by numerous uncertainties due to manually extracted features, which makes the anomaly detection of isolating switches still challenging. In this paper, a vision-based anomaly detection method for isolating switches, which uses the rotational angle of the switch system for more accurate and direct anomaly detection with the help of deep learning (DL) and image processing methods (Single Shot Multibox Detector (SSD), improved frame differencing method, and Hough transform), is proposed. The SSD is a deep learning method for object classification and localization. In addition, an improved frame differencing method is introduced for better feature extraction and a hough transform method is adopted for rotational angle calculation. A number of experiments are conducted for anomaly detection of single and multiple switches using video frames. The results of the experiments demonstrate that the SSD outperforms the You-Only-Look-Once network. The effectiveness and robustness of the proposed method have been proven under various conditions, such as different illumination and camera locations using 96 videos from the experiments.

다중경로 이득 적응형 MMSE 검출기에 관한 연구 (A Study on the Multi-Path Gain Adaptive MMSE Detector)

  • 유동관
    • 한국컴퓨터정보학회논문지
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    • 제9권2호
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    • pp.89-96
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    • 2004
  • 본 논문은 STBC CDMA시스템의 다중 사용자 환경을 위한 기존의 MMSE검출방식이 여러 경로의 수신신호 중에서 가장 전력이 강한 신호만을 사용하므로 상대적으로 검출능력이 떨어지는 단점이 있어 이를 보완하고자 다중 경로에 대한 이득을 추가로 적용시켜 성능을 개선시킨 다음에 이것의 성능을 기존 방식과 비교 분석하여 보았다. 개선된 검출방식의 성능 분석은 비트오율 확률분포 관점에서 이루어졌으며 이것을 기존 방식과 비교한 결과 다중경로 이득을 적용시킨 검출방식이 기존의 방식보다 채널의 지연 값, 사용자 수, 신호대 잡음에 대한 비트 오율 확률분포의 성능이 더 향상됨을 알 수 있었다.

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공동주택 리모델링 사업 분담금 산정의 문제점 및 개선방안 (Improved Methods of Cost Sharing in Apartment Remodeling Projects)

  • 김정원;이동진;이민주;이지형
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 추계 학술논문 발표대회
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    • pp.184-185
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    • 2019
  • The purpose of this study is to suggest the improved methods for cost sharing in apartment remodeling projects. Case studies on apartment remodeling projects with different plan type were analyzed and compared. Cost sharing estimated by 'proportional rate method' shows similar results estimated by 'return on investment method' in case of similar area ratio of existing plan to remodeling plan. Otherwise cost sharing estimated by 'proportional rate method' shows great differences comparing the results estimated by 'return on investment method'. Although return on 'proportional rate method' is widely used, it is not proper to estimate cost sharing when each householder's contribution for the project varies, such as considerable differences area ratio of existing plan to remodeling plan. Improved cost sharing method is needed taking into account project contribution and characteristics.

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