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Absence Importance and Its Application to Feature Detection and Matching

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International Journal of Automation and computing 2016年第5期13卷 480-490页

作者： Zhi-Heng Wang Qin-Feng Song Hong-Min Liu zhan-qiang huo School of Computer Science and Technique Henan Polytechnic University

Feature detection and matching play important roles in many fields of computer vision, such as image understanding, feature recognition, 3D-reconstruction, video analysis, etc. Extracting features is usually the first step for feature detection or matching, and the gradient feature is one of the most used selections. In this paper, a new image feature-absence importance （AI） feature, which can directly characterize the local structure information, is proposed. Greatly different from the most existing features, the proposed absence importance feature is mainly based on the consideration that the absence of the important pixel will have a great effect on the local structure. Two absence importance features, mean absence importance （MAI） and standard deviation absence importance （SDAI）, are defined and used subsequently to construct new algorithms for feature detection and matching. Experiments demonstrate that the proposed absence importance features can be used as an important complement of the gradient feature and applied successfully to the fields of feature detection and matching.

关键词： Absence importance (AI) feature detection feature matching mean absence importance (MAI) standard deviation absence importance (SDAI).

Image Inpainting Based on Structural Tensor Edge Intensity Model

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International Journal of Automation and computing 2021年第2期18卷 256-265页

作者： Jing Wang Yan-Hong Zhou Hai-Feng Sima zhan-qiang huo Ai-Zhong Mi College of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454003China

In the exemplar-based image inpainting approach,there are usually two major problems:the unreasonable calculation of priority and only considering the color features in the patch lookup *** this paper,we propose an image inpainting approach based on the structural tensor edge intensity ***,we use the progressive scanning inpainting method to avoid the image filling order being affected by the priority ***,we use the edge intensity model to build the patches similarity function for correctly identifying the local image ***,the balance operator is used to restrict the excessive propagation of structural information to ensure the correct structural *** experimental results show that the our approach is comparable and even superior to some state-of-the-art inpainting algorithms.

关键词： Exemplar-based technique image inpainting structural tensor edge intensity model structure propagation balance operator

Modeling and performance evaluation of the sleep mode in the IEEE 802.16e wireless networks with self-similar traffic

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 34-41页

作者： huo zhan-qiang JIN Shun-fu TIAN Nai-shuo WANG Yan College of Information Science and Engineering Yanshan University Qinhuangdao 066004 China College of Science Yanshan University Qinhuangdao 066004 China School of Computer Science and Engineering Hebei University of Technology Tianjin 300401 China

IEEE 802.16e is currently the latest broadband wireless access standard designed to support mobility. In mobile networks, how to control energy consumption is one of the most important issues for battery-powered mobile stations. The standard proposes an energy saving mechanism named ＇sleep mode＇ for conserving the power of mobile stations. According to the operation principle of the sleep mode for downlink traffic in the type I power saving class, considering the self-similar nature of massive multimedia data in wireless networks, a discrete-time batch arrival Geom^x/G/1 queuing model with a close-down time and multiple vacations is built. The batch size is supposed to be Pareto distributed. By employing an embedded Markov chain method, the average queue length and the average sojourn time of the system model are derived. Correspondingly, the performance measures are obtained of the energy saving rate and the average packet delay time for the sleep mode in the IEEE 802.16e. The numerical results demonstrate the dependency relationships between the system performance measures and the system parameters with different offered loads and different self-similar degrees. Furthermore, a cost model is developed to determine the optimum length of the close-down time for minimizing the total system cost.

关键词： IEEE 802.16e sleep mode close-down self-similar energy saving rate

Kinematics-based four-state trajectory tracking control of a spherical mobile robot driven by a 2-DOF pendulum

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Chinese Journal of Aeronautics 2019年第6期32卷 1530-1540页

作者： Wei LI qiang zhan Robotics Institute Beihang UniversityBeijing 100083China Ecole Centrale de Pékin Beihang UniversityBeijing 100083China

Spherical mobile robot has compact structure, remarkable stability, and flexible motion,which make it have many advantages over traditional mobile robots when applied in those unmanned environments, such as outer planets. However, spherical mobile robot is a special highly under-actuated nonholonomic system, which cannot be transformed to the classic chained form. At present, there has not been a kinematics-based trajectory tracking controller which could track both the position states and the attitude states of a spherical mobile robot. In this paper, the four-state(two position states and two attitude states) trajectory tracking control of a type of spherical mobile robot driven by a 2-DOF pendulum was studied. A controller based on the shunting model of neurodynamics and the kinematic model was deduced, and its stability was demonstrated with Lyapunov’s direct method. The control priorities of the four states were allocated according to the magnification of each state tracking error in order to firstly ensure the correct tracking of the position states. The outputs(motor speeds) of the controller were regulated according to the maximum speeds and the maximum accelerations of the actuation motors in order to solve the speed jump problem caused by initial state errors, and continuous and bounded outputs were obtained. The effectiveness including the anti-interference ability of the proposed trajectory tracking controller was verified through MATLAB simulations.

关键词： Kinematics Lyapunov methods Neurodynamics Nonholonomic systems Spherical mobile robot Trajectory tracking

Gelfand–Kirillov Dimensions of the Z^2-graded Oscillator Representations of sl(n)

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Acta Mathematica Sinica,English Series 2015年第6期31卷 921-937页

作者： zhan qiang BAI Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of Sciences

We find an exact formula of Gelfand-Kirillov dimensions for the infinite-dimensional explicit irreducible sl（n,F）-modules that appeared in the Z2-graded oscillator generalizations of the classical theorem on harmonic polynomials established by Luo and Xu. Three infinite subfamilies of these modules have the minimal Gelfand-Kirillov dimension. They contain weight modules with unbounded weight multiplicities and completely pointed modules.Service E-mail this articleAdd to my bookshelfAdd to citation managerE-mail AlertRSSArticles by authors

关键词： Gelfand-Kirillov dimension highest-weight module associated variety minimal GKdimension module universal enveloping algebra

Gelfand-Kirillov Dimension and Reducibility of Scalar Generalized Verma Modules for Classical Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 658-706页

作者： zhan qiang BAI Jing JIANG School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China E-mail:zqbai@*** jjsd6514@***

Let g be a classical complex simple Lie algebra and q be a parabolic *** M be a generalized Verma module induced from a one dimensional representation of *** M is called a scalar generalized Verma *** this paper,we will determine the reducibility of scalar generalized Verma modules associated to maximal parabolic subalgebras by computing explicitly the Gelfand-Kirillov dimension of the corresponding highest weight modules.

关键词： Generalized Verma module Gelfand-Kirillov dimension Young tableau

Microstructure refinement and work hardening in a machined surface layer induced by turning Inconel 718 super alloy

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 937-949页

作者： Xiao-ping Ren zhan-qiang Liu School of Mechanical Engineering Shandong University Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong University

The microstructural changes in the machined surface layer of Ni-based super alloys essentially determine the final performance of the structural components of aerospace engines in which these alloys are *** this work,multiscale metallurgical observations using scanning electron microscopy,electron-backscatter diffraction microscopy,and transmission electron microscopy were conducted to quantitatively characterize the microstructure of the machined ***,to elucidate the factors that affect the formation of the refinement microstructure,the distributions of the deformation parameters(strain,strain rate,and temperature) in the machined subsurface were analyzed.A dislocation–twin interaction dynamic recrystallization mechanism for grain refinement during machining of Inconel 718 is ***,microhardness evolution induced by grain refinement in the machined surface is *** results suggest that the gradient microstructure and the work hardening can be optimized by controlling the cutting parameters during turning of Inconel 718.

关键词： grain refinement dislocation–twin interaction work hardening turning Inconel 718

Prediction of temperature field in machined workpiece surface during the cutting of Inconel 718 coated with surface-active media

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Advances in Manufacturing 2023年第3期11卷 378-389页

作者： Qing-An Yin zhan-qiang Liu Bing Wang School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key National Demonstration Center for Experimental Mechanical Engineering Education/Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MQE Jinan 250061People's Republic of China

The heat generated and accumulated on the machined surface of an Inconel 718 workpiece causes thermal damage during the cutting ***-active media with high thermal conductivity coated on the workpiece to be machined may have the potential to reduce the generation of cutting *** this study,a theoretical model for predicting the instantaneous machined surface temperature field is proposed for surface-active thermal conductive medium(SACM)-assisted cutting based on the finite element and Fourier heat transfer *** cutting experiments were performed to verify the results predicted using the proposed surface-temperature field *** SACMs with various thermal conductivities were used to coat Inconel 718 surface to be *** embedded into the workpiece were used to measure the cutting temperature at different points on the machined workpiece surface during the cutting *** experimental results were in agreement with the predicted temperatures,and the maximum error between the experimental results and predicted temperatures was approximately 9.5%.The cutting temperature on the machined surface decreased with an increase in the thermal conductivity of the *** graphene SACM with high thermal conductivity can effectively reduce the temperature from 542℃ to 402℃,which corresponds to a reduction of approximately 26%.The temperature reduction due to SACM decreases with an increase in the distance between the temperature prediction point and machined workpiece *** conclusion,the cutting temperatures on the machined workpiece surface can be reduced by coating with SACM.

关键词： Surface-active thermal conductive media(SACM) Finite element model Cutting heat Cutting temperature Inconel 718

Akt Gene Therapy Enhances Angiogenesis in Ischemic Hind Limb

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Chemical Research in Chinese Universities 2010年第3期26卷 409-414页

作者： huo Xin zhanG qiang LIU Ying Department of Geriatrics First Affiliated Hospital China Medical University Shenyang 110001 P. R. China

Both bone marrow-derived mesenchymal stem cells（MSCs） therapy and gene therapy have been applied to animal studies and clinical trials. The goal of this study was to compare the effects of three types of MSCs transplantation. In the first part of the study, MSCs were transduced with the pEGFP-C1 and transfected with the pEGFP-C1/Akt in a model of bilateral hind limb ischemia in rats. Following gene transduction, the production of Akt and VEGF protein was more in the culture media of GFP-Akt/MSCs group than that in those of the GFP/MSCs group In the second part of the study, Sprague-Dawley rats（n=10/group） underwent surgery to create bilateral hind limb ischemia and were randomized into two groups consisting of a GFP/Akt-MSCs group（MSCs suspension, 1×10^7 MSCs/100 μL transfected pEGFP-C1/Akt） and a GFP-MSCs group（MSCs suspension, 1 × 10^7 MSCs/100 μL）. These PEGFP-C1/Akt and PEGFP-C 1 transfected MSCs suspensions were slowly infused into the adductor muscles of the rat＇s left hind limb, while the rat＇s right hind limb in the control group received an equal volume of PBS. Endpoints includes angiographic analysis, evaluation of capillary density, immunohistochemistry for von Willebrand factor （vWF）, immunodetection of Akt and VEGF protein, RT-PCR of VEGF and Akt mRNA levels in vitro and in vivo. Our data indicate that the tissue perfusion can improve capillary density and the mature of vasculature in the GFP-Akt/MSCs group compared to that in the GFP-MSCs group or control group in the rat model of bilateral hind limb ischemia. Transplantation of MSCs transfected with Akt gene may become the future therapy for hind limb ischemia.

关键词： Bone mesenchymal stem cell pEGFP-C1/Akt Hindlimb Ischemia Angiogenesis