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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 498-506页

作者： ming Yue Linjiu wang Teng Ma School of Automotive Engineering Dalian University of Technology State Key Laboratory of Robotics and System Harbin Institute of Technology

Wheeled mobile robots(WMRs) encounter unavoidable slippage especially on the low adhesion terrain such that the robots stability and accuracy are reduced *** overcome this drawback,this article presents a neural network(NN) based terminal sliding mode control(TSMC) for WMRs where an augmented ground friction model is reported by which the uncertain friction can be estimated and compensated according to the required *** contrast to the existing friction models,the developed augmented ground friction model corresponds to actual fact because not only the effects associated with the mobile platform velocity but also the slippage related to the wheel slip rate are concerned ***,the presented control approach can combine the merits of both TSMC and radial basis function(RBF) neural networks techniques,thereby providing numerous excellent performances for the closed-loop system,such as finite time convergence and faster friction estimation *** results validate the proposed friction model and robustness of controller;these research results will improve the autonomy and intelligence of WMRs,particularly when the mobile platform suffers from the sophisticated unstructured environment.

关键词： Ground friction radial basis function(RBF) neural network(NN) slippage effect terminal sliding mode control(TSMC) wheeled mobile robot(WMR)

Iterative learning based fault detection and estimation in nonlinear systems

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Journal of Systems Engineering and Electronics 2012年第3期23卷 419-424页

作者： Wei Cao wang Cong ming Sun College of Automation Harbin Engineering University Harbin 150001 E R. China College of Computer and Control Engineering Qiqihar University Qiqihar 161006 E R. China

Aiming at a class of nonlinear systems that contains faults, a novel iterative learning scheme is applied to fault detec- tion, and a novel algorithm of fault detection and estimation is proposed. This algorithm first constructs residual signals by the output of the practical system and the output of the designed fault tracking estimator, and then uses the residuals and the difference- value signal of the adjacent two residuals to gradually revise the introduced virtual faults, which can cause the virtual faults to close to the practical faults in systems, thereby achieving the goal of fault detection for systems. This algorithm not only makes full use of the existing valid information of systems and has a faster tracking con- vergent speed than the proportional-type （P-type） algorithm, but also calculates more simply than the proportional-derivative-type （PD-type） algorithm and avoids the unstable effects of differential operations in the system. The final simulation results prove the validity of the proposed algorithm.

关键词： iterative learning nonlinear system fault detection fault estimation.

Crack Fault Classification for Planetary Gearbox Based on Feature Selection Technique and K-means Clustering Method

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 242-252页

作者： Li-ming wang Yi-Min Shao State Key Laboratory of Mechanical Transmission Chongqing University

During the condition monitoring of a planetary gearbox, features are extracted from raw data for a fault ***, different features have different sensitivity for identifying different fault types, and thus, the selection of a sensitive feature subset from an entire feature set and retaining as much of the class discriminatory information as possible has a directly effect on the accuracy of the classification results. In this paper, an improved hybrid feature selection technique(IHFST) that combines a distance evaluation technique(DET), Pearson’s correlation analysis, and an ad hoc technique is proposed. In IHFST, a temporary feature subset without irrelevant features is first selected according to the distance evaluation criterion of DET, and the Pearson’s correlation analysis and ad hoc technique are then employed to find and remove redundant features in the temporary feature subset, respectively, and hence,a sensitive feature subset without irrelevant or redundant features is selected from the entire feature set. Further, the k-means clustering method is applied to classify the different kinds of health conditions. The effectiveness of the proposed method was validated through several experiments carried out on a planetary gearbox with incipient cracks seeded in the tooth root of the sun gear, planet gear, and ring gear. The results show that the proposed method can successfully distinguish the different health conditions of a planetary gearbox, and achieves a better classification performance than other methods. This study proposes a sensitive feature subset selection method that achieves an obvious improvement in terms of the accuracy of the fault classification.

关键词： Planetary gearbox Gear crack Feature selection technique K-means classification

Identification of Random Amplified Polymorphic DNA Markers Linked to Sex Determination in Calamus simplicifolius C. F. Wci

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Journal of Integrative Plant Biology 2005年第10期47卷 1249-1253页

作者： Hua YANG Si-ming GAN Guang-Tian YIN Huang-can XU Research Institute of Tropical Forestry Chinese Academy of Forestry Longdong Guangzhou 510520 China Zhejiang Academy of Forestry Hangzhou 310023 China

The random amplified polymorphic DNA （RAPD） molecular marker technique was used to determine the sex of Calamus simplicifolius C. F. Wei In the present study, DNA samples were extracted individually from 10 male and 10 female plants. After a total of 1 040 decamer primers had been tested, an approximate 500-bp male-specific DNA fragment was generated with the S 1443 primer. It is feasible to identify sex at the early stages of plant life, which is beneficial for improving breeding programs of this dioecious species. In addition, we have obtained a proper RAPD protocol that is useful for other species of rattan.

关键词： Calamus simplicifolius random amplified polymorphic DNA rattan sex determination.

Light intensification effect of trailing indent crack in fused silica subsurface

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Science China(Physics,Mechanics & Astronomy) 2015年第3期58卷 25-30页

作者： ZHANG ChunLai XU ming wang ChunDong Key Laboratory of Information Materials of Sichuan Province College of Electrical & Information Engineering Southwest University for Nationalities School of Physical Electronics University of Electronic Science and Technology of China Laboratory of Solid-State Physics and Magnetism Department of Physics and Astronomy

A finite-difference time-domain algorithm was applied to solve Maxwell＇s equations to obtain the redistribution of an electro- magnetic plane wave in the vicinity of a trailing indent crack （TIC）. The roles of five geometrical parameters playing in light intensification were calculated numerically under the irradiation of a 355-nm normal incidence laser. The results show that the light intensity enhancements between the nearest neighbor pits were remarkable, which may lead to damage, The calculated results reveal that the light intensity enhancement factor （LIEF） can be up to 11.2 when TIC is on the rear-surface. With the increase of the length as well as the depth of pits, LIEF increased. Conversely, with the increase of the axis of pits, LIEF grad- ually declined to a stable status. It was observed that there exists an optima width or gap, which enables LIEF to be increased dramatically and then decreased gently. By comparison, results suggest that the worst cases occur when the depth and the length are both very large, especially if the width equals to 22 and the gap equals the width. This work provides a recom- mended theoretical criterion for defect inspection and classification.

关键词： fused silica trailing indent crack finite-difference time-domain light intensification

Anti-apoptotic effect of Shudipingchan granule in the substantia nigra of rat models of Parkinson＇s disease

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Neural Regeneration Research 2016年第10期11卷 1625-1632页

作者： Qing Ye Xiao-lei Yuan Jing He Jie Zhou can-xingYuan Xu-ming Yang Department of Neurology Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai China College of Acupuncture and Manipulation Shanghai University of Traditional Chinese Medicine Shanghai China

Levodopa is the gold-standard treatment for Parkinson＇s disease. However, although it alleviates the clinical symptoms, it cannot delay the progressive apoptosis of dopaminergic neurons or prevent motor complications in the long term. In the present study, we investigated the effect of Shudipingchan granule on neuronal apoptosis in a rat model of Parkinson＇s disease, established by injecting 6-hydroxydopamine into the substantia nigra pars compacta and ventral tegmental area. We then administered levodopa （20 mg/kg intraperitoneally, twice daily） with or without Shudipingchan granule （7.5 mL/kg intragastrically, twice daily）, for 4 weeks. The long-term use of levodopa accel- erated apoptosis of nigral cells and worsened behavioral symptoms by activating the extracellular signal-regulated kinase pathway and downstream apoptotic factors. However, administration of Shudipingchan granule with levodopa reduced expression of phosphorylated extracellular signal-regulated kinase 1/2 and Bax, increased tyrosine hydroxylase and Bcl-2, reduced apoptosis in the substantia nigra, and markedly improved dyskinesia. These findings suggest that Shudipingchan granule suppresses neuronal apoptosis by inhibiting the hyper- phosphorylation of extracellular signal-regulated kinase and downregulating expression of anti-apoptotic genes. Shudipingchan granule, used in combination with levodopa, can effectively reduce the symptoms of Parkinson＇s disease.

关键词： nerve regeneration Parkinson's disease levodopa substantia nigra apoptosis Shudipingchan granule extracellular signal-regulatedkinase pathway behavior neural rege,eration

Chemical conversion coating on AZ31B magnesium alloy and its corrosion tendency

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Acta Metallurgica Sinica(English Letters) 2009年第1期22卷 65-70页

作者： Hualan JIN Xiangjie YANG ming wang School of Materials Science and Engineering Nanchang University Nanchang 330031 China School of Mechanical and Electronic Engineering Nanchang University Nanchang 330031 China

The morphology change of the magnesium matrix after pre-treatment and the morphology as well as the phase composition of chemical conversion coating formed by phosphate were studied using scanning electron microscope and X-ray diffraction. The corrosion resistance of the coating was studied by salt spray and damp test, and the corrosion tendency during salt immersion test was analyzed. The results show that the phase composition before and after pre-treatment is almost changeless, and the deep microflaw appears between a andβ phases during acidic pickling. The phosphate conversion coating is mainly composed of Mg, MgO, and some amorphous phase, and it can provide a good protection for the AZ31B alloy. Results from corrosive morphology indicate that the growth and the corrosion resistance of the phosphate conversion coating are related to the forming process of the AZ31B matrix.

关键词： Magnesium alloy Phosphate Chemical conversion coating Corrosion resistance

Velocity-free compact rigid flock control with input saturations

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Velocity-free compact rigid flock control with input saturat...

Role of PFKFB3 and CD163 in Oral Squamous Cell Carcinoma Angiogenesis

第25届中国控制与决策会议

作者： ming-can Fan Zhiyong Chen Hai-Tao Zhang the Department of Control Science and Engineering and State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology the School of Electrical Engineering and Computer Science University of Newcastle Callaghan NSW 2308 Australia

ISBN: (纸本)9781467355339

It is often encountered in industrial multi-agent systems the unavailability of velocity sensors or the imprecise measurements of velocities. This work addresses the velocityfree flock control problem with input saturation. Using algebraic graph theory and Barbalat’s Lemma, we prove that the algorithm guarantees the system to converge to a rigid flock behavior where all the agents in the group move with the same velocity. Moreover, the flock will converge to a prescribed tight formation which minimizes all agents’ global potentials. Finally, the proposed flock control method are examined by numerical simulations to show its effectiveness.

关键词： Flocking Multi-agent systems Velocity-free Input saturations

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Current Medical Science 2019年第3期39卷 410-414页

作者： Ji-jia LI Xiao-he MAO Tian TIAN Wei-ming wang Tong SU can-hua JIANG Chuan-yu HU Department of Oral and Maxillofacial Surgery Xiangya Hospital of Central South UniversityChangsha 410008China Center of Stomatology Tongji Hospital Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China

6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3 (PFKFB3), an enzyme producing fructose 2, 6-bisphosphate (F-2, 6-BP), serves as a switch to activate phosphofructokinase-1, and is a critical enzyme for endothelial glycolysis, mediating circadian control of carcinogenesis. Also, tumor-associated macrophages (TAMs) play an important role in the progression and prognosis of numerous cancers. However, the role and clinical significance of PFKFB3 and TAMs in oral squamous cell carcinoma (OSCC) have not been elucidated. The present study was designed to investigate the correlation between PFKFB3 expression, CD 163+ TAMs infiltration and tumor angiogenesis in OSCC by tissue microarray. Tissue microarrays containing 117 OSCC specimens and 56 matched paracarcinoma tissues were studied by immunohistochemistry. The expression levels of PFKFB3, CD163 and CD31 were significantly increased in OSCC specimens as compared with normal oral mucosa (Pcantly correlated with tumor differentiation and tumor size (Pcantly correlated with areca nut chewing habit among OSCC tissues (Pcantly correlated with both CD 163 and CD31 (Pcantly correlated with CD31 (P<0.001), suggesting PFKFB3 may promote angiogenesis in tumor progression and metastases by regulating CD 163+ TAMs infiltration in OSCC.

关键词： 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 angiogenesis CD163 CD31

Comparison of engineering failures and seismic responses of 500 kV transformer-bushing systems in the 2022 Luding earthquake

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 1029-1041页

作者： Zhu wang Wu ming’er Xie Qiang Department of Structural Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures(Tongji University) Shanghai 200092China

Cemented and mechanically clamped types of end fittings(fitting-C and fitting-M)are commonly used in transformer *** the Luding Ms 6.8 earthquake that occurred in China on September 5,2022,all transformer bushings with the two types of end fittings in a 500 kV substation were ***-earthquake field investigations were conducted,and the failures of the two types of bushings were *** elementary simulation models of the transformer-bushing systems were developed to simulate the engineering failures,and further compute their seismic responses for *** results indicate that the hitch lugs of the connection flange are structurally harmful to seismic ***-M can decrease the bending stiffness of the bushing due to the flexible sealing rubber *** it provides a more flexible connection that dissipates energy,the peak accelerations and relative displacements at the top of the bushing are significantly lower than those of the bushing with *** with fitting-C,fitting-M transfers the high-stress areas from the connection flange to the root of the porcelain,so the latter becomes the most vulnerable ***-M increases the failure risk of the low-strength porcelain,indicating the unsuitability of applying it in high-intensity fortification regions.

关键词： transformer bushing end fitting Luding earthquake,engineering failure seismic responses