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Managing economic and social profit of cooperative models in three-echelon reverse supply chain for waste electrical and electronic equipment

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Frontiers of Environmental Science & Engineering 2017年第5期11卷 125-134页

作者： Jian li Zhen Wang bao Jiang College of Economics Ocean University of China Qingdao 266100 China Marine Development Studies Institute Ocean University of China Qingdao 266100 China

In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment （WEEE）. The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In acldition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain fbr WEEE.

关键词： Waste electrical and electronic equipment(WEEE)Reverse supply chains Recycle quantitySocial benefit Cooperative models Duopolistic retailers

Experimental Research of Force Feedback Dataglove Based on Pneumatic Artificial Muscle

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 489-495页

作者： SUN Zhongsheng bao Gang li Xiaoning School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Pneumatic Center Harbin Institute of Technology Harbin 150008 China

Force feedback dataglove is an important interface of human-machine interaction between manipulator and virtual assembly system, which is in charge of the bidirectional transmission of movement and force information between computer and operator. The exoskeleton force feedback dataglove is designed taking the pneumatic artificial muscle as actuator, meanwhile, its structure and work principle are introduced, and the force control problem is analyzed and researched by experiment. The mathematic model of grasping rigid object for finger is established. Considering the friction of tendon-sheath system and finger deformation, the closed-loop force control for a single joint, a single finger and multi-fingers are studied respectively by the feedforward proportional-integral（PI） control method with variable arguments. On the premise of the force smoothness, the control error of the force exerted on the finger joint is in the range of ±0.25 N, which meets the requirement of force feedback. By experimental analysis, the reason of force fluctuation is that the finger joint has a small amplitude quiver, and the consistent change tendency of the force between proximal interphalangeal（PIP） joint and distal interphalangeal（DIP） joint results from their angle coupling relationship.

关键词： virtual reality dataglove force feedback pneumatic artificial muscle

Thermal transport mechanism of electrons and phonons in pristine and defective HfB_(2)

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Rare Metals 2023年第11期42卷 3651-3661页

作者： Ao Wang Shou-Hang li Hua bao Global Institute of Future Technology Shanghai Jiao Tong UniversityShanghai200240China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai200240China College of Mechanical Engineering Donghua UniversityShanghai201620China

Hafnium diboride(HfB_(2))is an important metallic ceramic that works in harsh environments,due to its high strength and thermal *** the thermal conductivity of HfB_(2) has been measured,the experimental results are ***,the thermal transport mechanism of HfB_(2) is not well *** this work,we study the thermal transport in both pristine and defective HfB_(2) from first-principles *** the pristine HfB_(2),the room-temperature thermal conductivities are 175.0 and 157.7 W·m^(-1)·K^(-1)on a-and c-axes,respectively,where the contributions from electron and phonon are *** Lorenz number is significantly smaller than the Sommerfeld value and shows a temperature dependence,which demonstrates that the Wiedemann-Franz law cannot be used to estimate electronic thermal *** phonon-isotope and the phonon-electron scattering are non-negligible compared to the phonon-phonon *** the defective HfB_(2),the grain size effects are negligible with length scales larger than 1μ*** pore can limit thermal conductivity when its occupancy is larger than 10%.The vacancy is found to induce scattered results in *** phonon thermal conductivity significantly reduces even with only 1%vacancy,while the electronic thermal conductivity is not sensitive to the *** study provides an in-depth understanding of the thermal transport in HfB_(2),and the revealed mechanisms provide important guidance on the design of HfB_(2)-based materials.

关键词： Thermal conductivity Electrical transport properties Boltzmann transport equation Vacancy scattering First-principles calculation

Syndrome series of one point algebraic-geometric codes and majority voting scheme

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Chinese Science Bulletin 1998年第7期43卷 540-544页

作者： bao li Guozhen Xiao Xidian Univ Inst Informat Secur Xian 710071 Peoples R China

A type of recurring relations on syndrome series is presnted. After some important theorems are established, an algorithm for computing a minimal polynomial set is presented. Finally an algorithm for determining the u... 详细信息

关键词： algebraic-geometric code decoding recurring relation majority voting.

Azimuth resolution improvement for spaceborne SAR images with quasi-non-overlapped Doppler bandwidth

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Journal of Systems Engineering and Electronics 2014年第3期25卷 422-427页

作者： Yanyang liu Zhenfang li Zhiyong Suo Jinwei li Zheng bao National Laboratory of Radar Signal Processing Xidian University

The azimuth resolution improvement problem is solved via a coherent combination of synthetic aperture radar （SAR） ima-ges with the quasi-non-overlapped Doppler bandwidth. Prior to the spectra combination, SAR images should be coregistered, while phase biases induced by topography, atmospheric propagation delays and baseline measurement errors should be calibrated. However, the coregistration accuracy suffers from large Doppler decorrelation caused by the quasi-non-overlapped Doppler band-width. Furthermore, the method used to estimate phase biases from interferogram of azimuth prefiltered SAR image pairs wil fail when there is no overlapped spectrum. The fringe simulation and maximum sharpness optimization are adopted to deal with the problems. Accordingly, a novel algorithm to coherently synthesize SAR images is presented. The experiment with the Terra SAR X-band （TerraSAR-X） satel ite data validates the performance of the presented method.

关键词： synthetic aperture radar (SAR) azimuth resolution improvement maximum sharpness optimization fringe simulation.

Extracting compressive stress-strain curve based on stick-slip shear banding process in bulk metallic glasses

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Journal of Iron and Steel Research International 2017年第4期24卷 372-377页

作者： Jing Hu Yun-xuan Weng Xiao-li li bao-an Sun School of Material and Mechanical Engineering Beijing Technology and Business University Herbert Gleiter Institute of Nanoscience Nanjing University of Science & Technology

Based on the stick-slip process,an effective method to extract the stress-strain curve directly from the crosshead displacement-load raw data in compression of bulk metallic glasses was *** method was tested in two bulk metallic glass samples with different plasticities and shear band *** extracted stress-strain curves were found to well resemble the stress-strain curve measured by a laser *** addition,the extracted curve could resolve fine structures of serrated flow much better than that measured by extensometer,thus facilitating the study of shear banding *** obtained by this method made the stick-slip dynamics of shear banding valid,and this method could be employed to obtain the real strain of small-sized metallic glass samples where extensometer cannot be applied.

关键词： Serrated flow Shear banding Stick-slip Stress-strain curve

Discontinuous Galerkin Finite Element Method for a Nonlinear Boundary Value Problem

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 521-532页

作者： Tie ZHANG Jian-bao li Department of Mathematics Northeastern University

In this paper, we investigate the a priori and a posteriori error estimates for the discontinuous Galerkin finite element approximation to a regularization version of the variational inequality of the second kind. We show the optimal error estimates in the DG-norm （stronger than the H1 norm） and the L2 norm, respectively. Furthermore, some residual-based a posteriori error estimators are established which provide global upper bounds and local lower bounds on the discretization error. These a posteriori analysis results can be applied to develop the adaptive DG methods.

关键词： variational inequality DG method optimal error estimate a posteriori error analysis

Astrophysical constraints on a parametric equation of state for neutron-rich nucleonic matter

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Nuclear Science and Techniques 2018年第12期29卷 62-70页

作者： Nai-Bo Zhang bao-An li Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Institute of Space Sciences Shandong University Department of Physics and Astronomy Texas A&M University-Commerce

Extracting the equation of state(EOS) and symmetry energy of dense neutron-rich matter from astrophysical observations is a long-standing goal of nuclear astrophysics. To facilitate the realization of this goal, the feasibility of using an explicitly isospin-dependent parametric EOS for neutron star matter was investigated recently in [1–3]. In this contribution, in addition to outlining the model framework and summarizing the most important findings from [1–3], we report a few new results regarding constraining parameters characterizing the highdensity behavior of nuclear symmetry energy. In particular,the constraints on the pressure of neutron star matter extracted from combining the X-ray observations of the neutron star radius, the minimum–maximum mass M=2:01 M_⊙, and causality condition agree very well with those extracted from analyzing the tidal deformability data by the liGO ? Virgo Collaborations. The limitations of using the radius and/or tidal deformability of neutron stars to constrain the high-density nuclear symmetry energy are discussed.

关键词：中子星物质天体物理学方程状态核子数据提取调查结果模型框架

Effect of strip feeding into mold on fluid flow and heat transfer in continuous casting process

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Journal of Iron and Steel Research International 2020年第3期27卷 295-309页

作者： Ran Niu bao-kuan li Zhong-qiu liu Xiang-long li School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Steel strip feeding into the mold during continuous casting is known as an innovative *** newly applied technology is designed to further improve the slab *** analyze the complex phase change processes,molten sodium thiosulphate(Na2S2O3-5H2O)was used in the experimental investigation as a transparent analog for metallic ***,a numerical model incorporating fluid flow,heat transfer and phase change during strip feeding into the mold process was *** generalized enthalpy-based method was applied to describe the phase change behavior,and the porous media theory was used to model the blockage of fluid flow by the dendrites in the mushy zone between the strip and melt as well as the solidified shell and *** validated model was then used for the simulation of the real strip feeding into the mold process in an industrial *** whole shape of the strip under the effect of jet flow from the submerged entry nozzle(SEN)was *** show that the strip will reach a pseudo-steady state after experiencing steel sheath formation,steel sheath melting and strip melting *** using the feeding method that is the strip narrow side toward the SEN in the present condition,the strip immersion length can reach 4.5 m below the meniscus and the slab centerline temperature can be decreased by 21 K to a *** the strip feeding speed increased from 0.3 to 0.5 m/s,the minimum temperature of the centerline could be lowered by 4 K or so.

关键词： Steel strip feeding Generalized enthalpy method Solidification Melting Continuous casting