• Title/Summary/Keyword: Improved Experiments

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Improved Dynamic Subjective Logic Model with Evidence Driven

  • Qiang, Jiao-Hong;Xin, Wang-Xin;Feng, Tian-Jun
    • Journal of Information Processing Systems
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    • v.11 no.4
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    • pp.630-642
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    • 2015
  • In Jøsang's subjective logic, the fusion operator is not able to fuse three or more opinions at a time and it cannot consider the effect of time factors on fusion. Also, the base rate (a) and non-informative prior weight (C) could not change dynamically. In this paper, we propose an Improved Subjective Logic Model with Evidence Driven (ISLM-ED) that expands and enriches the subjective logic theory. It includes the multi-agent unified fusion operator and the dynamic function for the base rate (a) and the non-informative prior weight (C) through the changes in evidence. The multi-agent unified fusion operator not only meets the commutative and associative law but is also consistent with the researchers's cognitive rules. A strict mathematical proof was given by this paper. Finally, through the simulation experiments, the results show that the ISLM-ED is more reasonable and effective and that it can be better adapted to the changing environment.

Enhanced Equivalent Circuit Modeling for Li-ion Battery Using Recursive Parameter Correction

  • Ko, Sung-Tae;Ahn, Jung-Hoon;Lee, Byoung Kuk
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1147-1155
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    • 2018
  • This paper presents an improved method to determine the internal parameters for improving accuracy of a lithium ion battery equivalent circuit model. Conventional methods for the parameter estimation directly using the curve fitting results generate the phenomenon to be incorrect due to the influence of the internal capacitive impedance. To solve this phenomenon, simple correction procedure with transient state analysis is proposed and added to the parameter estimation method. Furthermore, conventional dynamic equation for correction is enhanced with advanced RC impedance dynamic equation so that the proposed modeling results describe the battery dynamic characteristics more exactly. The improved accuracy of the battery model by the proposed modeling method is verified by single cell experiments compared to the other type of models.

Comparison of MPPT Control Method Characteristic for Stand-alone PV System (독립형 태양광 발전시스템의 MPPT 제어기법 특성비교)

  • Lee, Yong-Sik;Kim, Nam-In;Jeong, Sung-Won;Gim, Jae-Hyeon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.1
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    • pp.75-79
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    • 2012
  • Maximum power point tracking(MPPT) techniques are used in photovoltaic systems to maximize the PV array output power by tracking continuously the maximum power point which depends on panels temperature and on irradiance conditions. This paper proposes a variable step size MPPT algorithm which can improve the MPPT speed and accuracy. Depending on insolation and temperature, the MPPT controller gives optimized step size. The effectiveness of the proposed system is verified thorough PSIM simulation and experiments on a 50[W] prototype. The experimental results confirm that the PV power of the improved P&O method is higher than that of the traditional P&O method.

An Improved Method for Monitoring of Soil Moisture Using NOAA-AVHRR Data

  • Fu, June;Pang, Zhiguo;Xiao, Qianguang
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.195-197
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    • 2003
  • Soil moisture is a crucial variable in research works of hydrology, meteorology and plant sciences. Adequate soil moisture is essential for plant growth; excesses and deficits of soil moisture must be considered in agricultural practices. There are already several remote sensing methods used for monitoring soil moisture, such as thermal inertia, vegetation water-supplying index, crop water stress index and multi-factor regression. In this paper, an improved method has been discussed which is based on the thermal inertia. We analyzed the problems of monitoring soil moisture using satellites at first, and then put forward an simplified method which directly uses land surface temperature differences to measure soil moisture. Also we have taken the influence of vegetation into account, and import NDVI into the model. The method was used in the study of soil moisture in Heilongjiang Province, China, and we draw the conclusion by the experiments that the model can evidently increase the precision of monitoring soil moisture.

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Aircraft Recognition from Remote Sensing Images Based on Machine Vision

  • Chen, Lu;Zhou, Liming;Liu, Jinming
    • Journal of Information Processing Systems
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    • v.16 no.4
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    • pp.795-808
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    • 2020
  • Due to the poor evaluation indexes such as detection accuracy and recall rate when Yolov3 network detects aircraft in remote sensing images, in this paper, we propose a remote sensing image aircraft detection method based on machine vision. In order to improve the target detection effect, the Inception module was introduced into the Yolov3 network structure, and then the data set was cluster analyzed using the k-means algorithm. In order to obtain the best aircraft detection model, on the basis of our proposed method, we adjusted the network parameters in the pre-training model and improved the resolution of the input image. Finally, our method adopted multi-scale training model. In this paper, we used remote sensing aircraft dataset of RSOD-Dataset to do experiments, and finally proved that our method improved some evaluation indicators. The experiment of this paper proves that our method also has good detection and recognition ability in other ground objects.

A Recommendation System using Dynamic Profiles and Relative Quantification

  • Lee, Se-Il;Lee, Sang-Yong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.7 no.3
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    • pp.165-170
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    • 2007
  • Recommendation systems provide users with proper services using context information being input from many sensors occasionally under ubiquitous computing environment. But in case there isn't sufficient context information for service recommendation in spite of much context information, there can be problems of resulting in inexact result. In addition, in the quantification step to use context information, there are problems of classifying context information inexactly because of using an absolute classification course. In this paper, we solved the problem of lack of necessary context information for service recommendation by using dynamic profile information. We also improved the problem of absolute classification by using a relative classification of context information in quantification step. As the result of experiments, expectation preference degree was improved by 7.5% as compared with collaborative filtering methods using an absolute quantification method where context information of P2P mobile agent is used.

Operational modal analysis of structures by stochastic subspace identification with a delay index

  • Li, Dan;Ren, Wei-Xin;Hu, Yi-Ding;Yang, Dong
    • Structural Engineering and Mechanics
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    • v.59 no.1
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    • pp.187-207
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    • 2016
  • Practical ambient excitations of engineering structures usually do not comply with the stationary-white-noise assumption in traditional operational modal analysis methods due to heavy traffic, wind guests, and other disturbances. In order to eliminate spurious modes induced by non-white noise inputs, the improved stochastic subspace identification based on a delay index is proposed in this paper for a representative kind of stationary non-white noise ambient excitations, which have nonzero autocorrelation values near the vertical axis. It relaxes the stationary-white-noise assumption of inputs by avoiding corresponding unqualified elements in the Hankel matrix. Details of the improved stochastic subspace identification algorithms and determination of the delay index are discussed. Numerical simulations on a four-story frame and laboratory vibration experiments on a simply supported beam have demonstrated the accuracy and reliability of the proposed method in eliminating spurious modes under non-white noise ambient excitations.

An improved cross-correlation method based on wavelet transform and energy feature extraction for pipeline leak detection

  • Li, Suzhen;Wang, Xinxin;Zhao, Ming
    • Smart Structures and Systems
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    • v.16 no.1
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    • pp.213-222
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    • 2015
  • Early detection and precise location of leakage is of great importance for life-cycle maintenance and management of municipal pipeline system. In the past few years, acoustic emission (AE) techniques have demonstrated to be an excellent tool for on-line leakage detection. Regarding the multi-mode and frequency dispersion characteristics of AE signals propagating along a pipeline, the direct cross-correlation technique that assumes the constant AE propagation velocity does not perform well in practice for acoustic leak location. This paper presents an improved cross-correlation method based on wavelet transform, with due consideration of the frequency dispersion characteristics of AE wave and the contribution of different mode. Laboratory experiments conducted to simulate pipeline gas leakage and investigate the frequency spectrum signatures of AE leak signals. By comparing with the other methods for leak location identification, the feasibility and superiority of the proposed method are verified.

One-Ampere Conductor Method for Tubular Linear Induction Motor for Size Reduction of Primary Iron Core

  • Lee, Byeong-Hwa;Kim, Kyu-Seob;Kwon, Soon-O;Sun, Tao;Hong, Jung-Pyo;Lee, Jung-Ho
    • Journal of Magnetics
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    • v.16 no.1
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    • pp.46-50
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    • 2011
  • This paper presents size reduction of primary iron core for tubular linear induction motor by improved winding configuration. Using one-ampere conductor method, magnetic field analysis of tubular linear induction motor for size reduction is conducted. Size reduction and improvement of air gap flux distribution is achieved by improved winding configuration, and analysis results are verified by finite element analysis (FEA) and experiments.

Model updation using multiple parameters influencing servoelastic response of a flexible aircraft

  • Srinivasan, Prabha;Joshi, Ashok
    • Advances in aircraft and spacecraft science
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    • v.4 no.2
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    • pp.185-202
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    • 2017
  • In a flexible airvehicle, an assessment of the structural coupling levels through analysis and experiments provides structural data for the design of notch filters which are generally utilized in the flight control system to attenuate the flexible response pickup. This is necessitated as during flight, closed loop control actuation driven with flexible response inputs could lead to stability and performance related problems. In the present work, critical parameters influencing servoelastic response have been identified. A sensitivity study has been carried out to assess the extent of influence of each parameter. A multi-parameter tuning approach has been implemented to achieve an enhanced analytical model for improved predictions of aircraft servoelastic response. To illustrate the model updation approach, initial and improved test analysis correlation of lateral servoelastic responses for a generic flexible airvehicle are presented.