• 제목/요약/키워드: scaling factor

검색결과 459건 처리시간 0.023초

UNDERSTANDING SERVICE QUALITY: A MULTIDIMENSIONAL SCALING APPROACH

  • Lee, Dong-Won;Kim, Youn-Sung
    • 품질경영학회지
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    • 제32권3호
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    • pp.68-80
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    • 2004
  • This paper purports to uncover the underlying attributes used by customers to gauge service quality. Data was collected by administering questionnaires to 50 respondents and then analyzed by using Multidimensional Scaling methodology. The findings indicate that there are two primary dimensions to service quality. This analysis helped determine us two alternatives to naming the dimensions. Experience properties of service and Price value of the service, or Responsiveness of service provider employees and Reliability of service providers.

UNDERSTANDING SERVICE QUALITY: A MULTIDIMENSIONAL SCALING APPROACH

  • Lee Dongwon;Kim Youn Sung
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 2004년도 품질경영모델을 통한 가치 창출
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    • pp.639-645
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    • 2004
  • This paper purports to uncover the underlying attributes used by customers to gauge service quality. Data was collected by administering questionnaires to 50 respondents and then analyzed by using Multidimensional Scaling methodology. The findings indicate that there are two primary dimensions to service quality. A considerable analysis helped determine two alternatives to naming the dimensions: Experience properties of service and Price value of the service, or Responsiveness of service provider employees and Reliability of service providers.

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Sum rate and Energy Efficiency of Massive MIMO Downlink with Channel Aging in Time Varying Ricean Fading Channel

  • Yang, Lihua;Yang, Longxiang;Zhu, Hongbo;Liang, Yan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권3호
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    • pp.1098-1112
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    • 2018
  • Achievable sum rate and energy efficiency (EE) are investigated for the massive multiple-input multiple-output (Massive MIMO) downlink with channel aging in the time varying Ricean fading channel. Specifically, the expression of the achievable sum rate of the system for the maximum ratio transmission (MRT) precoder with aged channel state information (CSI) in the time varying Ricean fading channel is first presented. Based on the expression, the effect of both channel aging and the Ricean factor on the power scaling law are studied. It is found that the transmit power of base station (BS) is scaled down by $1/{\sqrt{M}}$(where M is the number of the BS antennas) when the Ricean factor K is equal to zero (i.e., time varying Rayleigh fading channel), indicating that aged CSI does not affect the power scaling law. However, the transmit power of the BS is scaled down by 1/M for the time varying Ricean fading channel (where $K{\neq}0$) indicating that the Ricean factor affects the power scaling law and sum rate, and channel aging only leads to a reduction of the sum rate. Second, the EE of the system is analyzed based on the general power consumption model. Both the theoretical analysis and the simulations show that the channel aging could degrade the sum rate and the EE of the system, and it does not affect the power scaling law.

최적화기법을 이용한 퍼지 제어기의 비선형 이득요소 동조 (Nonlinear Scaling Factors tuning of Fuzzy Controller using Optimization Techniques)

  • 류동완;권재철;서보혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 B
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    • pp.705-707
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    • 1997
  • An optimal tuning algorithm of scaling factors is presented in this paper to automatically improve the performance of fuzzy controller. Especially, fuzzy controller has determined an moderate Scaling factor through trial and error. The presented method estimates automatically the optimal values of I/O scaling factors, using modified steepest descent method and this optimal tuning is for nonlinear input/output scaling factors. Simulation results verify the validity of the presented method.

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SOAP를 이용한 원격 퍼지 논리 제어시스템 (Remote Fuzzy Logic Control System using SOAP)

  • 이경웅;최한수
    • 제어로봇시스템학회논문지
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    • 제13권4호
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    • pp.329-334
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    • 2007
  • This paper deals with self-tuning of fuzzy control systems. The fuzzy logic controller(FLC) has parameters that an: input and output scaling factors to effect control output. Tuning method is proposed for the scaling factor. In this paper. it is studied to control and to monitor the remote system statues using SOAP for communicate between the server part and the client part. The remote control system is controlled by using a web browser or a application program. The server part is waiting for the request of client part that uses internet network for communication each other and then the request is reached. the server part saves client data to the database and send a command set to the client part and then the client part sends command to controller in a cool chamber. The administrator can control and monitor the remote system just using a web browser. The effects of membership functions, defuzzification methods and scaling factors are investigated in the FLC system.

유전알고리즘을 이용한 이득요소 동조 퍼지 제어기 최적설계 (Optimal Design of Scaling Factor Tuning of Fuzzy Logic Controller Using Genetic Algorithm)

  • 황용원;오진수;박근화;홍영준;남문현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 B
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    • pp.897-899
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    • 1999
  • This paper presents a scaling factor tuning method to improve the performance of fuzzy logic controller. Tuning rules and reasoning are utilized off-line to determine the scaling factors based on absolute value of the error and its difference. In this paper We proposed a new method to generate fuzzy logic controllers throught genetic algorithm. The developed approach is subsequently applied to the design of proportional plus integral type fuzzy controller for a dc-servo motor control system. The performance of this control system is demonstrated higher than a conventional fuzzy logic controller(FLC).

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퍼지 규칙기반제어기에서 시스템의 성능평가 (The Performance Evaluation of Fuzzy Rule-Based System)

  • 김영철;최종수;최한수;김성중
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 A
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    • pp.261-264
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    • 1992
  • In designing the fuzzy rule-based system, it has effected by the four significant factors such as the choice of membership function, scaling factor, the numbers of fuzzy control rule, the method of defuzzification. In this paper we design the fuzzy rule based system and evaluate by three factors, as followes reaching time, overshoot, and amplitude. And then we wiII show that the significant factors are the choice of scaling factor and the numbers of fuzzy control rule, and the system performance can be improved by the proper selection of the scaling factors.

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적응진화연산과 퍼지 로직을 이용한 퍼지 제어기의 이득요소 동조 (Scaling Factor Tuning of Fuzzy Controller Using Adaptive Evolutionary Computation and Fuzzy Logic)

  • 김종율;황기현;문경준;김형수;박준호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 B
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    • pp.404-406
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    • 1998
  • In this paper, we propose a scaling factor tuning method to improve the performance of fuzzy controller. Tuning rules and reasoning are utilized on-line to determine the scaling factors based on absolute value of the error and its difference. A adaptive evolutionary computation (AEC) is used to search for the optimal tuning rules that will maximize the fitness function. Finally, the proposed fuzzy controller is applied to the angular stabilization of an inverted pendulum.

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인공신경망 이론을 이용한 척도인자 결정방법의 향상방안에 관한 연구 (A Study on the Improvement of Scaling Factor Determination Using Artificial Neural Network)

  • Sang-Chul Lee;Ki-Ha Hwang;Sang-Hee Kang;Kun-Jai Lee
    • 방사성폐기물학회지
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    • 제2권1호
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    • pp.35-40
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    • 2004
  • Final disposal of radioactive waste generated from Nuclear Power Plant (NPP) requires the detailed information about the characteristics and the quantities of radionuclides in waste package. Most of these radionuclides are difficult to measure and expensive to assay. Thus it is suggested to the indirect method by which the concentration of the Difficult-to-Measure (DTM) nuclide is estimated using the correlations of concentration - it is called the scaling factor - between Easy-to-Measure (Key) nuclides and DTM nuclides with the measured concentration of the Key nuclide. In general, the scaling factor is determined by the log mean average (LMA) method and the regression method. However, these methods are inadequate to apply to fission product nuclides and some activation product nuclides such as 14$^{C}$ and 90$^{Sr}$ . In this study, the artificial neural network (ANN) method is suggested to improve the conventional SF determination methods - the LMA method and the regression method. The root mean squared errors (RMSE) of the ANN models are compared with those of the conventional SF determination models for 14$^{C}$ and 90$^{Sr}$ in two parts divided by a training part and a validation part. The SF determination models are arranged in the order of RMSEs as the following order: ANN model

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비마커 영상기반 변위계측 시스템을 이용한 구조물의 동특성 측정 (Measurement of Dynamic Characteristics on Structure using Non-marker Vision-based Displacement Measurement System)

  • 최인섭;김준희
    • 한국전산구조공학회논문집
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    • 제29권4호
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    • pp.301-308
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    • 2016
  • 본 연구에서는 마커없이 구조물의 변위를 측정할 수 있는 영상기반 변위계측 시스템(NVDMS)을 제안한다. 기존의 방식과 제안하는 NVDMS는 크게 두 가지의 차이점이 있다. 첫째, NVDMS는 마커를 사용하지 않고 구조물의 특징점의 픽셀좌표 변화를 추출한다. 둘째, 특징점의 픽셀좌표를 물리좌표로 변환하는 scaling factor는 기존 방식에선 마커의 크기로부터 계산되는 반면, NVDMS에서는 카메라와 구조물사이의 거리, 각도, 초점거리로 계산된다. 3층 축소모형의 자유진동 실험에서 제안한 NVDMS로부터 얻은 변위데이터의 신뢰도를 분석하기 위해 LDS로부터 얻은 변위데이터의 비교를 하였으며, 얻어진 변위데이터를 이용하여 동특성을 분석하였다. 분석결과 NVDMS는 마커없이 구조물의 동적변위를 정밀하게 측정가능할 뿐만 아니라 얻어진 변위데이터로부터 추출한 동특성의 신뢰도 또한 높았다.