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A SMOOTHING CONJUGATE GRADIENT ALGORITHM FOR NONLINEAR COMPLEMENTARITY PROBLEMS

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 460-472页

作者： Caiying wu guoqing CHEN College of Mathematics Science Inner Mongolia University Hohhot 010021 China

A PRP-type smoothing conjugate gradient method for solving large scale nonlinear complementarity problems （NCP（F）） is proposed. At each iteration, two Armijo line searches are performed, which guarantees the positive property of the smoothing parameter and minimizes the merit function formed by Fischer-Burmeister function, respectively. Global convergence is studied when F：R^n→R^n is a continuously differentiable P0 ＋ R0 function. Numerical results show that the method is efficient.

关键词： Nonlinear complementarity conjugate gradient global convergence Fischer-Burmeister function

Microstructure and wear properties of the electroslag remelting layer reinforced by TiC particles

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Journal of University of Science and Technology Beijing 2008年第6期15卷 769-774页

作者： Qianlin wu Yangshan Sun guoqing Li School of Material Science and Engineering Southeast University Nanjing 211189 China

The electroslag remelting （ESR） layer reinforced by TiC particles was obtained by electroslag remelting. The microstructure and wear properties of the ESR layer were studied by means of scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and wear test. The results indicate that TiC particles are synthesized by self-propagating high-temperature synthesis （SHS） reaction during the electroslag remelting process. The size of TiC particles is in the range of 1-10 μm, and the distribution of TiC particles is uniform, from outside to inside of the ESR layer, and the volume fraction and the size of TiC particles decrease gradually. Molten iron and slag flow into porosity due to the SHS process leading to rapid densification and the elimination of porosity in the ESR layer during the ESR process. TiC particles enhance the wear resistance of the ESR layer, whereas CaF2 can improve the high temperature lubricating property of the ESR layer.

关键词： electroslag remelting (ESR) TiC particles porosity wear resistance lubricating property

Load Forecasting of the Power System: An Investigation Based on the Method of Random Forest Regression

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Energy Engineering 2021年第6期118卷 1703-1712页

作者： Fuyun Zhu guoqing wu College of Mechanical and Electrical Engineering Soochow UniversitySuzhou215137China

Accurate power load forecasting plays an important role in the power dispatching and security of *** this paper,a mathematical model for power load forecasting based on the random forest regression(RFR)was *** input parameters of RFR model were determined by means of the grid search *** prediction results for this model were compared with those for several other common machine learning *** was found that the coefficient of determination(R^(2))of test set based on the RFR model was the highest,reaching 0.514 while the corresponding mean absolute error(MAE)and the mean squared error(MSE)were the ***,the impacts of the air conditioning system used in summer on the power load were *** calculation results showed that the introduction of indexes in the field of Heating,Ventilation and Air Conditioning(HVAC)could improve the prediction accuracy of test set.

关键词： Mathematical model machine learning power load HVAC

Mixed mode oscillations as well as the bifurcation mechanism in a Duffing’s oscillator with two external periodic excitations

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Science China(Technological Sciences) 2019年第10期62卷 1816-1824页

作者： ZHANG XiaoFang ZHENG JianKang wu guoqing BI QinSheng Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang212013China School of Mechanical Engineering Nantong Institute of TechnologyNantong226002China

The main purpose of the paper is to present an approach to account for the mechanism of bursting oscillations occurring in the systems with multiple periodic excitations. Since the traditional slow-fast analysis method can be used only for the systems with two scales in time domain, when there exists an order gap between the exciting frequencies and the natural frequency, how to explore the mechanism of the complicated dynamics remains an open problem, especially for the case when two exciting terms exist. To explain our approach, a relative simple Duffing’s oscillator with two external periodic excitations is introduced as an example. For the case when one exciting frequency is integer times of the other exciting frequency, by employing Moivre’s equation, the two exciting terms can be transformed into the functions of one basic periodic exciting term. Regarding the basic periodic exciting term as a slow-varying parameter, the two exciting terms can be changed into the functions of the slow-varying parameter, based on which the whole model can be transformed into a generalized autonomous system with one slow-varying parameter. Equilibrium branches as well as the related bifurcations of the generalized autonomous system can be derived with the variations of the amplitudes of the two excitations, which describes the relationship between the state variables of the generalized autonomous system and the slow-varying parameter. Considering the slow-varying parameter as a generalized state variable, one may obtain the so-called transformed phase portraits, which present the relationship between the state variable and the slowvarying parameter. The bifurcation mechanism of the mixed oscillations can be obtained by overlapping the equilibrium branches and the transformed phase portraits. Upon the approach, different types of bursting oscillations are presented. It is pointed that when the trajectory moves almost strictly along the segments of the stable equilibrium branches

关键词： multiple external periodic excitations two scales in frequency domain bursting oscillations bifurcation mechanism

Semi-supervised Software Defect Prediction Using Task-Driven Dictionary Learning

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Chinese Journal of Electronics 2016年第6期25卷 1089-1096页

作者： CHENG Ming wu guoqing YUAN Mengting WAN Hongyan School of Computer Wuhan University State Key Laboratory of Software Engineering Wuhan University

We present a semi-supervised approach for software defect prediction. The proposed method is designed to address the special problematic characteristics of software defect datasets, namely, lack of labeled samples and class-imbalanced data. To alleviate these problems, the proposed method features the following components. Being a semi-supervised approach, it exploits the wealth of unlabeled samples in software systems by evaluating the confidence probability of the predicted labels, for each unlabeled sample. And we propose to jointly optimize the classifier parameters and the dictionary by a task-driven formulation, to ensure that the learned features(sparse code) are optimal for the trained classifier. Finally, during the dictionary learning process we take the different misclassification costs into consideration to improve the prediction performance. Experimental results demonstrate that our method outperforms several representative stateof-the-art defect prediction methods.

关键词： Software defect prediction Task-driven dictionary learning Cost-sensitive Semi-supervised learning Sparse representation

VOLUME DEFECT FATIGUE FAILURE OF CERAMIC BALLS UNDER ROLLING CONDITION

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Chinese Journal of Mechanical Engineering 2007年第2期20卷 47-51页

作者： ZHOU Jingling wu guoqing CHEN Xiaoyang College of Mechanical Engineering Nantong University Nantong 226007 China School of Mechatronical Engineering and Automation Shanghai University Shanghai 200072 China

A newly developed pure rolling fatigue test rig with three contact points is used to test the rolling contact fatigue properties of silicon nitride ceramic balls. Ball surfaces are examined after failure with optical microscopy and scanning electron microscopy. The failure cause, fatigue phenomenon and mechanics are analyzed. The research shows that subsurface cracks play a dominant role in the formation of spalling failure. These cracks originated from volume defects of the material and propagate, to form elliptical fatigue spalls under the action of principal tensile stresses. The principal tensile stress increases with increasing contact load, causing spall formation and reduction of rolling contact life. The greater the principal tensile stress is, the more severe the peeling of near surface is. Under the same condition, the closer volume defects are to the surface, the more likely failure occurs, the shorter the rolling contact life is.

关键词： Silicon nitride Pure rolling Fatigue failure Volume defect

The Dynamic Checking of Complex Real Time System

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wuhan University Journal of Natural Sciences 2006年第3期11卷 529-532页

作者： YU Chao HUANG Benwen wu guoqing School of Computer Wuhan University Wuhan 430072 Hubei China School of Mathematics and Statistics Wuhan University Wuhan 430072 Hubei China

The paper presents an dynamic execution model of complex real-time software based on requirement description model RTRSM, and then propose a checking method based on configuration covering and its corresponding algorithm. This checking method can check the execution situations between parallel elements in a dynamic execution step of real-time software systems. It also can check all the states and transitions which assure the completeness of checking. In the end, related theorem is proofed.

关键词： RTRSM configuration dynamic execution model

DFF-ResNet: An Insect Pest Recognition Model Based on Residual Networks

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Big Data Mining and Analytics 2020年第4期3卷 300-310页

作者： Wenjie Liu guoqing wu Fuji Ren Xin Kang the School of Information Science and Technology and School of Transportation and Civil Engineering Nantong UniversityNantong 226019China the Faculty of Engineering Tokushima UniversityTokushima 770-8506Japan the School of Information Science and Technology Nantong UniversityNantong 226019China

Insect pest control is considered as a significant factor in the yield of commercial ***,to avoid economic losses,we need a valid method for insect pest *** this paper,we proposed a feature fusion residual block to perform the insect pest recognition *** on the original residual block,we fused the feature from a previous layer between two 11 convolution layers in a residual signal branch to improve the capacity of the ***,we explored the contribution of each residual group to the model *** found that adding the residual blocks of earlier residual groups promotes the model performance significantly,which improves the capacity of generalization of the *** stacking the feature fusion residual block,we constructed the Deep Feature Fusion Residual Network(DFF-ResNet).To prove the validity and adaptivity of our approach,we constructed it with two common residual networks(Pre-ResNet and Wide Residual Network(WRN))and validated these models on the Canadian Institute For Advanced Research(CIFAR)and Street View House Number(SVHN)benchmark *** experimental results indicate that our models have a lower test error than those of baseline ***,we applied our models to recognize insect pests and obtained validity on the IP102 benchmark *** experimental results show that our models outperform the original ResNet and other state-of-the-art methods.

关键词： insect pest recognition deep feature fusion residual network image classification

A Requirements Engineering Environment for Embedded Real-Time Software—SREE

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wuhan University Journal of Natural Sciences 2006年第3期11卷 533-538页

作者： LI Yonghua SHU Fengdi wu guoqing LIANG Zhengping School of Computer Wuhan University Wuhan 430072 Hubei China Department of Computer Shenzhen UniversityShenzhen 518060 Guangdong China

The paper presents the embedded real-time software-oriented requirements engineering environment—SREZ. It involves the whole process of software requirements engineering, including the definition, analysis and checking of requirements ,specifications. We first explain the principles of the executable specification language RTRSM. Subsequently, we introduce the main functions of SREE, illustrate the methods and techniques of checking requirements specifications, especially how to perform simulation execution, combining prototyping method with RTRSM and animated representations. At last, we compare the SREE with other requirements specifications methods and make a summary for SREE＇s advantages.

关键词： embedded real-time system requirements specification requirements verification simulation execution