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Pathological verification of corticospinal tract Wallerian degeneration in a rat model of brain ischemia

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Neural Regeneration Research 2011年第13期6卷 1000-1004页

作者： Weijun Gong tong zhang Department of Neurological Rehabilitation Beijing Boai Hospital China Rehabilitation Research Center Capital Medical University Beijing100068 China

Although neuroimaging is commonly utilized to study Wallerian degeneration, it cannot display Wallerian degeneration early after brain injury. In the present study, we attempted to examine pathologically the process of Wallerian degeneration early after brain injury. Cerebral peduncle demyelination was observed at 3 weeks post brain ischemia, followed by demyelination in the cervical enlargement at 6 weeks. Anterograde tracing of the corticospinal tract with biotinylated dextran amine showed that following serious neurologic deficit, the tracing of the corticospinal tract of the intemal capsule, cerebral peduncle, and cervical enlargement indicated serious Wallerian degeneration.

关键词： brain ischemia corticospinal tract Wallerian degeneration pathology neural regeneration

Closed form solution of stress intensity factors for cracks emanating from surface semi-spherical cavity in finite body with energy release rate method

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Applied Mathematics and Mechanics(English Edition) 2016年第12期37卷 1689-1706页

作者： Hualiang wan Qizhi wanG Xing zhang Institute of Solid Mechanics Beihang University Beijing 100191 China

In this paper, a new semi-analytical and semi-engineering method of the closed form solution of stress intensity factors （SIFs） of cracks emanating from a surface semi-spherical cavity in a finite body is derived using the energy release rate theory. A mode of crack opening displacements of a normal slice is established, and the normal slice relevant functions are introduced. The proposed method is both effective and accurate for the problem of three-dimensional cracks emanating from a surface cavity. A series of useful results of SIFs are obtained.

关键词： stress intensity factor (SIF) closed form solution surface cavity three-dimensional crack normal slice

Model reduction for supersonic cavity flow using proper orthogonal decomposition(POD)and Galerkin projection

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Applied Mathematics and Mechanics(English Edition) 2017年第5期38卷 723-736页

作者： Chao zhang Zhenhua wan Dejun SUN Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China

The reduced-order model （ROM） for the two-dimensional supersonic cavity flow based on proper orthogonal decomposition （POD） and Galerkin projection is investigated. Presently, popular ROMs in cavity flows are based on an isentropic assumption, valid only for flows at low or moderate Mach numbers. A new ROM is constructed involving primitive variables of the fully compressible Navier-Stokes （N-S） equations, which is suitable for flows at high Mach numbers. Compared with the direct numerical simulation （DNS） results, the proposed model predicts flow dynamics （e.g., dominant frequency and amplitude） accurately for supersonic cavity flows, and is robust. The comparison between the present transient flow fields and those of the DNS shows that the proposed ROM can capture self-sustained oscillations of a shear layer. In addition, the present model reduction method can be easily extended to other supersonic flows.

关键词： supersonic cavity flow reduced-order model (ROM) proper orthogonal decomposition (POD) Galerkin projection

Adsorption of Au(Ⅲ) by amino-modified monodispersed PGMA microspheres and deposition of gold nanoparticles

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Rare Metals 2018年第3期37卷 196-203页

作者： Fu-Chun wang Jun-Mei Zhao wan-Kun wang Zi-Zheng tong School of Materials and Metallurgical Engineering Guizhou Institute of Technology Institute of Process Engineering Chinese Academy of Sciences

Monodispersed poly（glycidyl methacrylate）（PGMA） microspheres with various amounts of amino groups（PGMA-NH2） were used to adsorb Au（Ⅲ） from simulated wastewaters. Gold nanoparticle-coated PGMA functional microspheres can be directly obtained via the adsorption process. The adsorption kinetics follows pseudo-second model, and 10 min is enough for reaching at equilibrium. The adsorption isotherm follows Langmuir model, and the adsorption amounts for Au（Ⅲ） are 8.25 and 21.75 mol·kg^-1 at 298 and 328 K, respectively. The relative separation coefficients between Au（Ⅲ）, Pt（Ⅵ）, Pd（Ⅱ）and Co（Ⅱ）, Cu（Ⅱ）; Ni（Ⅱ）, Fe（Ⅲ） are all higher than 100 when 1 〈 pH 〈 3. Furthermore, the characterization analysis of X-ray diffraction（XRD）, thermogravimetrydifferential scanning calorimetry（TG-DSC）, scanning electron microscopy-energy dispersive spectroscopy（SEM-EDS）, transmission electron microscopy（TEM） and Fourier transform infrared spectroscopy（FTIR） confirms that AuCl4^-has been reduced to Au^0 nanoparticles and deposited onto the surface of PGMA-NH2. The current work shows a good prospect for PGMA-NH2 to be a valid adsorbent for the recovery of gold and the possible fabrication of gold nanoparticles by reduction-deposition process without any reductant.

关键词： PGMA microspheres AuCl4^- Amino groups Adsorption Reduction-deposition Elemental gold

Key Technology of Embedded System Implementation for Software-based CNC System

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 217-224页

作者： wan Jiafu LI Di zhang Ping College of Computer Science and Engineering South China University of Technology Guangzhou 510006 China School of Mechanical and Automotive Engineering South China University of Technology Guangzhou 510640 China Department of Computer Guangdong College of Mechanical and Electrical Technology Guangzhou 510515 China

The software-based computer numerical control（CNC） system includes three types of tasks： periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.

关键词： software-based CNC system embedded system implementation output jitter fuzzy feedback scheduling manufacturing accuracy

New family of piecewise smooth support vector machine

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Journal of Systems Engineering and Electronics 2015年第3期26卷 618-625页

作者： Qing Wu Leyou zhang wan wang School of Automation Xi'an University of Posts and Telecommunications School of Mathematics and Statistics Xidian University School of Computer Science and Technology Xi'an University of Posts and Telecommunications

Support vector machines （SVMs） have been extensively studied and have shown remarkable success in many applications. A new family of twice continuously differentiable piecewise smooth functions are used to smooth the objective function of uncon- strained SVMs. The three-order piecewise smooth support vector machine （TPWSSVMd） is proposed. The piecewise functions can get higher and higher approximation accuracy as required with the increase of parameter d. The global convergence proof of TPWSSVMd is given with the rough set theory. TPWSSVMd can efficiently handle large scale and high dimensional problems. Nu- merical results demonstrate TPWSSVMa has better classification performance and learning efficiency than other competitive base- lines.

关键词： support vector machine (SVM) piecewise smooth function smooth technique bound of convergence.

Dispersed distribution derived integrated anode for lithium ion battery

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Journal of Materials Science & Technology 2019年第10期35卷 2319-2324页

作者： Boya zhang Dongxiang Li Jiaqi wan College of Chemistry and Molecular Engineering Qingdao University of Science&TechnologyQingdao 266042China School of Materials Science and Engineering Qingdao University of Science&TechnologyQingdao 266042China

With the development of portable communication devices and electric vehicles, there is a great need for energy storage devices with lighter weight and higher energy density. In this paper, a new method by combining waster-paper-synthesized conductive paper(CP) and active material Mn O2 together is developed to obtain a new type of anode without any binder for lithium ion batteries. By this way, we can obtain low density anode with active material in CP, instead of the commonly-used heavy metal current collector. Also, binder has been abandoned, which are usually used to combine active material into anode, to further decrease weight. The multi walled carbon nanotube(MWCNT) was added in serves as a component of CP and the conductive agent for active material. Compared to traditional anode coated on Cu current collector, the CP-combined anode can greatly improve the electrochemical performance of active material Mn O2. It can let more particles to fully participate in the reaction and therefore boost the specific capacity to a great extent(about 3 times higher). It delivered an initial specific capacity of 1629.9 m A h g^-1 at a current density of 100 m A g^-1 and maintained about 67% even after 100 ***’s more, it shows reversible capacity of about 260 m A h g^-1 at high current density of 1000 m A h g^-*** original synthesis method of anode, which shows far-reaching referential value and environmental significance, can be generalized to other electrodes and other battery systems.

关键词： Light-weight electrode Composite anode Conductive network Lithium battery Environmental-friendly method

Improving Targeted Multimodal Sentiment Classification with Semantic Description of Images

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Computers, Materials & Continua 2023年第6期75卷 5801-5815页

作者： Jieyu An wan Mohd Nazmee wan Zainon zhang Hao School of Computer Sciences Universiti Sains MalaysiaPenang11800Malaysia

Targeted multimodal sentiment classification(TMSC)aims to identify the sentiment polarity of a target mentioned in a multimodal *** majority of current studies on this task focus on mapping the image and the text to a high-dimensional space in order to obtain and fuse implicit representations,ignoring the rich semantic information contained in the images and not taking into account the contribution of the visual modality in the multimodal fusion representation,which can potentially influence the results of TMSC *** paper proposes a general model for Improving Targeted Multimodal Sentiment Classification with Semantic Description of Images(ITMSC)as a way to tackle these issues and improve the accu-racy of multimodal sentiment ***,the ITMSC model can automatically adjust the contribution of images in the fusion representation through the exploitation of semantic descriptions of images and text similarity ***,we propose a target-based attention module to capture the target-text relevance,an image-based attention module to capture the image-text relevance,and a target-image matching module based on the former two modules to properly align the target with the image so that fine-grained semantic information can be *** experimental results demonstrate that our model achieves comparable performance with several state-of-the-art approaches on two multimodal sentiment *** findings indicate that incorporating semantic descriptions of images can enhance our understanding of multimodal content and lead to improved sentiment analysis performance.

关键词： Targeted sentiment analysis multimodal sentiment classification visual sentiment textual sentiment social media

Convergence Theorems of Common Elements for Equilibrium Problems and Fixed Point Problems

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Acta Mathematica Sinica,English Series 2012年第3期28卷 631-636页

作者： Li Juan zhang Hui tong College of Mathematics and Computer Hebei University

In this paper, we introduce an iterative method for finding a common element of the set of solutions of an equilibrium problem, the set of common fixed points of two asymptotically nonexpansive mappings in a Hilbert s... 详细信息

关键词： Equilibrium problems asymptotically nonexpansive mapping fixed point