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The Kinematic Analyses of the 3-DOF Parallel Machine Tools

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International Journal of Automation and computing 2011年第1期8卷 107-111页

作者： Ming Hu Jia-shun shi School of Mechanical Engineering and Automation Northeastern University Shenyang 110004 PRC

A 3-degree-of-freedom （3-DOF） parallel machine tool based on a tripod mechanism is developed and studied. The kinematics analysis is performed, the workspace is derived, and an analysis on the number of conditions of the Jacobian matrix and manipulability is carried out. A method for error analysis and manipulability is introduced. Hence, the manipulability analysis of the parallel machine tool is accomplished.

关键词： Parallel machine tool kinematics Jacobian matrix error workspace.

Control Structure Analysis and Recovery of Embedded Binaries

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Chinese Journal of Electronics 2017年第6期26卷 1118-1124页

作者： JI Weixing huo Yuanhong WANG Yizhuo GAO Yujin shi Feng Beijing Institute of Technology

Existing decompilers use rule-based algorithms to transform unstructured Control flow graph(CFG) into equivalent high-level programming language constructs with "goto" statements. One problem of such approaches is that they generate a large number of "goto"s in the output code, which reduce the readability and hinder the understanding of input binaries. A global search algorithm is proposed based on structural analysis. This algorithm restructures a CFG and generates fewer number of "goto" statements than the rule-based algorithm *** also present a Genetic algorithm(GA) for the global search approach to locate near optimal solutions for large CFGs. Evaluation results on a set of real CFGs show that the genetic algorithm-based heuristic for global search is capable of finding high-quality solutions.

关键词： Decompiling Control flow graph restructuring Structural analysis Genetic algorithm(GA)

Oscillation quenching and physical explanation on freeplay-based aeroelastic airfoil in transonic viscous flow

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Chinese Journal of Aeronautics 2023年第10期36卷 124-136页

作者： Yayun shi shun HE Gaowei CUI Gang CHEN Yan LIU State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Beijing Institute of Structure and Environment Engineering Beijing 100076China Shenyang Aircraft Design Institute Shenyang 110036China

Limit Cycle Oscillation(LCO)quenching of a supercritical airfoil(NLR 7301)considering freeplay is investigated in transonic viscous *** Fluid Dynamics(CFD)based on Navier-Stokes equations is implemented to calculate transonic aerodynamic forces.A loosely coupled scheme with steady CFD and an efficient graphic method are developed to obtain the aerodynamic *** quenching phenomenon is observed from the nonlinear dynamic aeroelastic response obtained by using time marching *** the airspeed increases,LCO appears then quenches,forming the first LCO *** the quenching region,LCO occurs again and sustains until the divergence of the response,forming the second LCO *** quenching of LCOs was addressed physically based on the aerodynamic preload and the linear flutter ***“island”of stable region is observed in the flutter boundary,*** flutter speed versus the mean Angle of Attack(AoA).The LCO quenches when the aerodynamic preload crosses this stable region with the increasing of *** LCO quenching of this model in transonic flow is essentially induced by destabilizing effect from aerodynamic preload,since the flutter speed is sensitive to AoA due to aerodynamic nonlinearity.

关键词： Freeplay Nonlinear aeroelasticity Supercritical airfoil Transonic flutter Unsteady flow

Biocompatible in situ-forming glycopolypeptide hydrogels

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Science China(Technological Sciences) 2020年第6期63卷 992-1004页

作者： shi shun YU ShuangJiang LI Gao HE ChaoLiang CHEN XueSi CAS Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China College of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Jilin Biomedical Polymers Engineering Laboratory Changchun 130022China

A lack of biological activity hinders the application of synthetic hydrogels in tissue engineering and regenerative ***,the use of glycopolypeptides in hydrogel synthesis may provide the materials with the desired biological ***,we prepared three in situ-forming hydrogels from various phenol-functionalized *** gelation time,mechanical properties,degradation properties,and biocompatibility of the hydrogels were *** time ranged from 11 to 380s,depending on the concentration of horseradish *** galactose-modified polypeptide hydrogel showed the highest storage modulus with an obvious stress relaxation *** prepared hydrogels exhibited good degradation properties and compatibility to cells and ***,the rate of immune cell accumulation around the mannosemodified polypeptide hydrogel was the fastest among the hydrogels.

关键词： in situ-forming hydrogels glycopolypeptide tissue engineering horseradish peroxidase

TRANSMISSION DYNAMICS AND OPTIMAL CONTROL OF AN INFLUENZA MODEL WITH QUARANTINE AND TREATMENT

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International Journal of Biomathematics 2012年第3期5卷 177-190页

作者： WEI-WEI shi YUAN-shun TAN Department of Applied Mathematics Xi ' an Jiaotong University Xi'an 710049 P. R. China School of Science Chongqing Jiaotong University Chongqing P. R. China

We develop an influenza pandemic model with quarantine and treatment, and analyze the dynamics of the model. Analytical results of the model show that, if basic repro- duction number R0 〈 1, the disease-free equilibrium （DFE） is globally asymptotically stable, if R0〉 1, the disease is uniformly persistent. The model is then extended to assess the impact of three anti-influenza control measures, precaution, quarantine and treat- ment, by re-formulating the model as an optimal control problem. We focus primarily on controlling disease with a possible minimal the systemic cost. Pontryagin＇s maximum principle is used to characterize the optimal levels of the three controls. Numerical sim- ulations of the optimality system, using a set of reasonable parameter values, indicate that the precaution measure is more effective in reducing disease transmission than the other two control measures. The precaution measure should be emphasized.

关键词： Influenza model equilibrium basic reproduction number stability persistence optimal control quarantine precaution.

L_p approximation by Bernstein-Kantorovich quasi-interpolants

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 200-208页

作者： LIU Li-xia shi Ling GUO shun-sheng College of Math. and Inform. Sci. Hebei Normal Univ. Shijiazhuang 050016 China

Bernstein-Kantorovich quasi-interpolants K^（2r-1）n（f, x） are considered and direct, inverse and equivalence theorems with Ditzian-Totik modulus of smoothness ω^2rφ（f, t）p （1 ≤ p ≤＋∞） are obtained.

关键词： quasi-interpolant Bernstein-Kantorovich operator Ditzian-Totik modulus

Global-local combined features to detect pain intensity from facial expression images with attention mechanism

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Journal of Electronic Science and Technology 2024年第3期22卷 80-93页

作者： Jiang Wu Yi shi shun Yan Hong-Mei Yan Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China MOE Key Laboratory for Neuroinformation School of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengdu611731China College of Engineering University of California at Santa BarbaraSanta Barbara93106USA

The estimation of pain intensity is critical for medical diagnosis and treatment of *** the development of image monitoring technology and artificial intelligence,automatic pain assessment based on facial expression and behavioral analysis shows a potential value in clinical *** paper reports a framework of convolutional neural network with global and local attention mechanism(GLA-CNN)for the effective detection of pain intensity at four-level thresholds using facial expression ***-CNN includes two modules,namely global attention network(GANet)and local attention network(LANet).LANet is responsible for extracting representative local patch features of faces,while GANet extracts whole facial features to compensate for the ignored correlative features between *** the end,the global correlational and local subtle features are fused for the final estimation of pain *** under the UNBC-McMaster Shoulder Pain database demonstrate that GLA-CNN outperforms other state-of-the-art ***,a visualization analysis is conducted to present the feature map of GLA-CNN,intuitively showing that it can extract not only local pain features but also global correlative facial *** study demonstrates that pain assessment based on facial expression is a non-invasive and feasible method,and can be employed as an auxiliary pain assessment tool in clinical practice.

关键词： Attention Convolutional neural network Facial expression Pain intensity

Evaluation of underground blast-induced ground motions through nearsurface low-velocity geological layers

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 600-617页

作者： Yonggang Gou Xiuzhi shi Zhi Yu Xiaofeng huo Xianyang Qiu College of Civil and Transportation Engineering Hohai UniversityNanjing210098China School of Resources and Safety Engineering Central South UniversityChangsha410083China Oulu Mining School University of OuluOuluFI-90014Finland

Surface ground motion produced by underground blasts is significantly influenced by near-surface geological ***,near-surface low-propagation velocity layers were always ignored in past analyses of ground motions due to their thin *** the rising concern about surface ground motions produced by the ascendant scale and frequentness of underground excavation and mining,close attention is gradually paid to ground blast ***,systemic experiments were conducted and took seven months in an underground mine to clarify the variation of motion from underground rock to surface *** attenuation of surface ground peak particle velocities(PPVs)is compared to that in underground rock,and horizontal amplitudes are compared to vertical *** between bedrock and surface ground vibrations are analyzed to illustrate the site effect of near-surface lower-propagation velocity ***-dimensional site response analysis is employed to quantify the influence of different geological profiles on surface ground *** experimental data and site response analysis allowed the following conclusions:(1)geological site effects mainly produce decreasing dominant frequency(DF)of surface ground vibrations;(2)the site amplification effect of blast vibration needs to be characterized by peak particle displacement(PPD);(3)shear waves(S-waves)begin to dominate and surface Rayleigh waves(R-waves)develop as blast-induced ground vibrations travel upward through rock and lower-velocity layers to the *** comparison of response relative displacement to a critical value is best to assess the potential for cracking on surface structures.

关键词： Surface ground motions Underground blasts Geological site condition Amplitude attenuation Site response analysis

An improved yeast two-hybrid approach for detection of interacting proteins

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Frontiers in Biology 2006年第2期1卷 120-126页

作者： Wan Bingbing shi Yan huo Keke State Key Laboratory of Genetic Engineering Institute of GeneticsSchool of Life SciencesFudan UniversityShanghai 200433China

Yeast two-hybrid approach is popularly used nowadays as an important technical method in the field of studying protein-protein *** yeast two-hybrid system is obviously advantageous in searching interacting proteins and setting up the network of proteins interaction,not all of proteins can use routine yeast two-hybrid method to search interacting *** important proteins,such as some nucleoprotein transcriptional factor,carry out the regular method and construct the bait-BD vector to screen the library containing AD ***,it usually results in failures because it contains the activate domain and can self-activate the reporter *** this study,we changed the research strategy,fused the bait gene(FOXA3)with the AD vector to screen the library containing BD vector,so that we constructed a two-hybrid library containing BD vector and can bypass the interference of *** we used this two-hybrid library to screen FOXA3,a hepatocyte nuclear factor,and found out an interacting protein:complement component C3.

关键词： yeast two-hybrid system protein-protein interaction human liver cDNA library FOXA3