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Self-Consistent Sources Extensions of Modified Differential-Difference KP Equation

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Communications in Theoretical Physics 2018年第4期69卷 357-366页

作者： Gegenhasi Ya-Qian Li duo-duo zhang School of Mathematical Sciences Inner Mongolia University Hohhot 010021 China

In this paper, we investigate a modified differential-difference KP equation which is shown to have a continuum limit into the m KP equation. It is also shown that the solution of the modified differential-difference KP equation is related to the solution of the differential-difference KP equation through a Miura transformation. We first present the Grammian solution to the modified differential-difference KP equation, and then produce a coupled modified differential-difference KP system by applying the source generation procedure. The explicit N-soliton solution of the resulting coupled modified differential-difference system is expressed in compact forms by using the Grammian determinant and Casorati determinant. We also construct and solve another form of the self-consistent sources extension of the modified differential-difference KP equation, which constitutes a B?cklund transformation for the differentialdifference KP equation with self-consistent sources.

关键词： modified differential-difference KP equation source generation procedure determinant solution Backlund transformation

Fast algorithm for simulation of normal and oblique penetration into limestone targets

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Applied Mathematics and Mechanics(English Edition) 2017年第5期38卷 671-688页

作者： Xuguang CHEN duo zhang Shujian YAO Fangyun LU College of Science National University of Defense TechnologyChangsha 410073China

A fast algorithm is proposed to predict penetration trajectory in simulation of normal and oblique penetration of a rigid steel projectile into a limestone target. The algorithm is designed based on the idea of isolation between the projectile and the target. Corresponding factors of influence are considered, including analytical load model, cratering effect, free surface effect, and separation-reattachment phenomenon. Besides, a method of cavity ring is used to study the process of cavity expansion. Further, description of the projectile＇s three-dimensional gesture is coded for fast calculation, named PENE3D. A presented. As a result, the algorithm is series of cases with selected normal and oblique penetrations are simulated by the algorithm. The predictions agree with the results of tests, showing that the proposed algorithm is fast and effective in simulation of the penetration process and prediction of the penetration trajectory.

关键词： fast algorithm isolation between projectile and target analytical loading model ogive-nosed projectile limestone target

Mutual-information based weighted fusion for target tracking in underwater wireless sensor networks

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Frontiers of Information Technology & Electronic Engineering 2018年第4期19卷 544-556页

作者： duo zhang Mei-qin LIU Sen-lin zhang Zhen FAN Qun-fei zhang State Key Laboratory of Industrial Control Technology Zhejiang University College of Electrical Engineering Zhejiang University School of Marine Science and Technology Northwestern Polytechnical University

Underwater wireless sensor networks(UWSNs)can provide a promising solution to underwater target *** to limited energy and bandwidth resources,only a small number of nodes are selected to track a target at each *** all measurements are fused together to provide information in a fusion center,fusion weights of all selected nodes may affect the performance of target *** far as we know,almost all existing tracking schemes neglect this *** study a weighted fusion scheme for target tracking in ***,because the mutual information(MI)between a node’s measurement and the target state can quantify target information provided by the node,it is calculated to determine proper fusion ***,we design a novel multi-sensor weighted particle filter(MSWPF)using fusion weights determined by ***,we present a local node selection scheme based on posterior Cramer-Rao lower bound(PCRLB)to improve tracking ***,simulation results are presented to verify the performance improvement of our scheme with proper fusion weights.

关键词： Target tacking Fusion weight Mutual information Node selection Underwater wireless sensor networks

Flow Field and Heat Transfer Analysis of Local Structure for Regenerative Cooling Panel

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Journal of Thermal Science 2012年第2期21卷 172-178页

作者： Yu Feng Hongyan Huang Tao Li duo zhang Zhongqi Wang Harbin Institute of Technology No. 92 Xidazhi Street 150001 Harbin China

Local structure of cooling panel has great effects on the heat transfer in the cooling channel for the scramjet. The problems of flow dead area and mass flow rate non-uniform distribution caused by the local structure effect the cooling effectiveness in the channel seriously. Numerical simulation to the flow field of scramjet cold panel with four different fuel injection island structures respectively has been carried out using the CFD commercial software-CFX in this research. The results reveal that flow dead area has been eliminated and flow field has been improved for the optimized structure. Furthermore, local resistance loss has been decreased and the mass flow rate non-uniform distribution in the channel has been reduced. Based on the optimized results, some suggestions about the local design of cooling panel have been proposed in this research.

关键词： numerical simulation cooling panel fuel injection island

Numerical model and hydrodynamic performance of tuna finlets

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Theoretical & Applied Mechanics Letters 2022年第1期12卷 56-64页

作者： Jun-duo zhang Wei-Xi Huang AML Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

Finlets, a series of small individual triangular fins located along the dorsal and ventral midlines of the body, are remarkable specializations of tuna and other scombrid fishes capable of high-speed swimming. In this study, a symmetric model containing nine finlets of tuna is proposed to overcome the limitation of measurement without losing authenticity. Hydrodynamic performance along with three-dimensional flow structures obtained by direct numerical simulation are demonstrated to disclose the underlying hydrodynamics mechanism of finlets. Complex interactions of leading-edge vortices(LEVs), trialing-edge vortices(TEVs), tip vortices(TVs) and root vortices(RVs) are observed from the three-dimensional vortical structures around the finlets. Two more cases consisting of the 3rd to 9th(without the first two) and the 3rd to 7th(without the first two and the last two) finlets are also simulated to examine the effects of the first two and the last two finlets.

关键词： Tuna Finlets Thunniform swimming Leading-edge vortex Vortex interactionw

Investigations on the Droplet Impact onto a Spherical Surface with a High Density Ratio Multi-Relaxation Time Lattice-Boltzmann Model

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Communications in Computational Physics 2014年第9期16卷 892-912页

作者： duo zhang K.Papadikis Sai Gu Xi’an Jiaotong-Liverpool University No.111 Ren’ai RoadSuzhou Dushu Lake Higher Education TownSuzhouChina 215123. School of Engineering University of LiverpoolBrownlow HillLiverpoolL697ZXUnited Kingdom School of Engineering Cranfield UniversityBedfordshire MK430ALUnited Kingdom.

In the current study,a two-dimensional multi-relaxation time(MRT)lattice Boltzmann model which can tolerate high density ratios and low viscosity is employed to simulate the liquid droplet impact onto a curved *** temporal variation of the film thickness at the north pole of the target surface is *** different temporal phases of the dynamics behavior,namely,the initial drop deformation phase,the inertia dominated phase and the viscosity dominated phase are reproduced and *** effect of the Reynolds number,Weber number and Galilei number on the film flow dynamics is *** addition,the dynamic behavior of the droplet impact onto the side of the curved target is shown,and the effect of the contact angle,the Reynolds number and the Weber number are investigated.

关键词： Multiphase flow MRT Lattice Boltzmann high-density-ratio droplet impact film thickness dynamic behavior.

Highly reversible Zn anode enabled by anticatalytic carbon layer with suppressed hydrogen evolution

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Rare Metals 2024年第7期43卷 3044-3054页

作者： Wen-duo zhang Chuang Sun Yu-Xuan Zhu Feng Gao Chao Lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou221116China

Aqueous zinc-ion batteries(AZIBs)have emerged as a promising high-efficiency energy storage system due to the high energy density,low-cost and environmental ***,the practical application of AZIBs is severely restricted by the challenges faced by the Zn anode,which include uncontrollable dendrite growth,corrosion and hydrogen evolution ***,a simple and convenient physical vapor deposition(PVD)method is reported for fabricating uniform graphite as a protection layer on the surface of Zn *** high conductivity graphite layer on Zn anode(denoted as Zn@C)not only benefits the uniform distribution of the electric field,but also provides numerous Zn nucleation sites to regulate and navigate Zn-ion stripping/plating ***,the graphite layer with a poor catalytic activity endows the Zn@C anode with a highly suppressed hydrogen ***,a hydrogen and dendrite free anode is achieved with artificial anticatalytic carbon layer on Zn anode,exhibiting a high reversibility and excellent cycling stability over 2600 h at the current density of 5 mA·cm^(-2)with a capacity of 2.5 mAh·cm^(-2)and longtime cycling stability for assembled full *** work strategically designs the properties of the artificial interface layer to effectively address various challenges simultaneously,which presents insights for the future development of high-performance rechargeable AZIBs.

关键词： Zn metal anode Artificial anticatalytic layer Hydrogen suppression Dendrite free

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

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Communications in Theoretical Physics 2024年第5期76卷 77-85页

作者： duo zhang Ke Wang Kunpeng Zhao Mei Wang Zhaoyu Sun School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property

Clinical characteristics of perineal endometriosis:A case series

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World Journal of Clinical Cases 2021年第5期9卷 1037-1047页

作者： Yan Liang duo zhang Ling Jiang Yuan Liu Jian zhang Department of Obstetrics and Gynecology International Peace Maternity and Child Health HospitalShanghai 200030China Department of Radiology International Peace Maternity and Child Health HospitalShanghai 200030China Department of Pathology International Peace Maternity and Child Health HospitalShanghai 200030China

BACKGROUND The prevalence of perineal endometriosis(PEM)is low among women with endometriosis(EM)treated by *** manifests as hard or cystic nodules with pain in the perineal wounds and surrounding *** theory is regarded as the main pathogenesis of *** are few clinical studies on the incidence and clinical characteristics of *** study aims to summarize the clinical data of 14 PEM cases and analyze the factors that may be related to the incubation period and *** To analyze the medical history,clinical manifestations,diagnosis,treatment and treatment effect of *** The present study is a case *** collected the clinical data and follow-up data of 14 patients with PEM who visited The International Peace Maternal and Child Health Hospital Affiliated to Shanghai Jiaotong University from January 2009 to December *** t test and Pearson correlation analysis were used for statistical analysis.P<0.05 was considered statistically *** The 14 patients included had a history of vaginal *** patients underwent PEM lesion *** patients were treated by levator ani muscle repair at the same time and 1 patient underwent extensive PEM lesion resection and anal sphincter *** mass index(BMI)at delivery and BMI within 1 mo after delivery were negatively correlated with the latent period,respectively(R2=0.53/0.86,P<0.05).The average visual analog scale score in lesions at the third month after surgery was 0.57±1.28 for all patients,which was significantly lower than that prior to surgery(P<0.05).One patient relapsed during the sixth month after surgery,and to date,no recurrence occurred after the second *** The higher the BMI during delivery and within 1 mo after delivery,the shorter the incubation period of *** is very important to evaluate the location of lesions before *** resection of the lesion is the best treatment for PEM and results in significant allev

关键词： Perineal endometriosis Incubation period Pain in the perineum Surgery Body mass index Clinical characteristics