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TRAVELING WAVE SOLUTIONS FOR A PREDATOR-PREY MODEL WITH BEDDINGTON-DEANGELIS FUNCTIONAL RESPONSE

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Annals of Applied Mathematics 2020年第3期36卷 221-234页

作者： Zhuanling Gao Xiangkui zhao zhihong zhao School of Mathematics and Physics University of Science&Technology BeijingBeijing 100083PR China

In this paper,we study a class of predator-prey models with Beddington-De Angelis functional *** the predator equation has singularity in zero prey population,where a smoothing auxiliary function is introduced to overcome *** aim is to see if the predator and prey can eventually survive when an alien predator enters the habitat of an existing prey by employing traveling wave solutions,based on the upper and lower solutions and Schauder’s fixed point *** addition,the non-existence of traveling wave solutions is discussed by the comparison *** the same time,some simulations are carried out to further verify the results.

关键词： predator-prey model Beddington-DeAngelis traveling wave solution existence

Current Status of Left Atrial Appendage Thrombus with Atrial Fibrillation

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Cardiology Discovery 2023年第3期3卷 203-211页

作者： zhihong zhao Xingwei Zhang Department of Cardiology Afliated Hospital of Hangzhou Normal UniversityHangzhou Institute of Cardiovascular DiseasesHangzhouZhejiang 310015China

Cardiac thrombus in patients with atrial fibrillation (AF) is most commonly found in the left atrial appendage (LAA). The incidence of LAA thrombus ranges from 1.2% to 22.6%, with the vast variation in incidence attributed to the patient’s condition. The effective rate of anticoagulation for thrombus dissolution therapy is only 50%-60%, and long-term anticoagulation treatment increases the risk of bleeding. Direct percutaneous LAA closure in AF patients with LAA thrombus in a suitable location is another alternative treatment option. LAA resection with cardiac surgery is also an effective treatment. This review presents the development of the incidence, diagnosis, and treatment of thrombus in LAA.

关键词： Atrial fibrillation Left atrial appendage thrombus Treatment

Efficacy of Watchman occlusion of the left atrial appendage in patients ≥85 years with atrial fibrillation

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China Medical Abstracts(Internal Medicine) 2022年第2期39卷 100-101页

作者： zhao zhihong Dept Cardiol Shanghai Pudong New Area Zhoupu HospShanghai Med&Health Sci UnivShanghai 201318

Objective To analyze the safety and efficacy of left atrial appendage closure(LAAC) with Watchman in patients≥85 years with atrial fibrillation(AF).Methods515 elderly patients with atrial fibrillation, including 73patients aged 85 years or older(85~91), who had undergone Watchman LAAC at Zhoupu Hospital affiliated to Shanghai Health Medical College from August 2016 to December 2020, were retrospectively analyzed.

关键词： patients atrial fibrillation

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岩石裂隙水-岩作用机制与力学行为研究

岩石力学与工程学报 2021年第S02期40卷 3063-3073页

作者：赵志宏清华大学土木工程系北京100084

水-岩作用是导致裂隙岩体发生灾变的主要原因之一,其中的关键科学问题是准确预测裂隙岩体力学性质在水-岩作用下的时空演化规律。首先给出岩石裂隙水-岩力学、物理、化学作用的基本概念,并通过理论推导和试验研究,揭示3种水-岩作用对岩... 详细信息

水-岩作用是导致裂隙岩体发生灾变的主要原因之一,其中的关键科学问题是准确预测裂隙岩体力学性质在水-岩作用下的时空演化规律。首先给出岩石裂隙水-岩力学、物理、化学作用的基本概念,并通过理论推导和试验研究,揭示3种水-岩作用对岩石裂隙力学行为的影响规律与内在机制。岩石裂隙有效应力系数的物理意义为其内部的空腔率,给出基于常规力学参数的岩石裂隙有效应力系数计算公式。岩石裂隙水-岩物理作用的主要机制是对基本摩擦角以及接触凸起体强度的降低。岩石裂隙的水-岩化学作用与溶液pH值密切相关,酸性溶液对岩石裂隙剪切参数的弱化效应最为显著,其次是碱性溶液和中性溶液。最后,给出考虑水-岩作用效应的岩石裂隙抗剪强度准则,并简要讨论其在实际工程中的应用前景。

关键词：岩石力学岩石裂隙水-岩作用有效应力理论模型直剪试验

Imitation of Fabric Flagging in the Wind with 1/F~β Noise

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武汉理工大学学报 2006年第S2期28卷 745-747页

作者： LI Beibei zhao zhihong GENG zhaofeng (Information Institute,DongHua University,Shanghai 200051,China, Information Institute DongHua UniversityShanghai 200051China

This paper presents a dynamic simulation model,based on noise,to simulate fabric flagging in the *** wind noise is generated by two sine functions defined in *** frequencies and amplitudes of these sine functions are change- able to presenting the basic model of the *** order to obtain more fabric fluctuant effect,we adopt a cosine function to achieve the fabric dynamic display *** the actual process,the traditional Phong illumination model is ***, the model of simulating fabric flagging in the wind can be built *** with the physical model shows that it is a fast arithmetic because of adopting a new model in stead of the time consuming iteration *** can achieve a friendly de- sign interface and an ideal simulation *** can select wind force and fabric material by controlling different parame- *** basic characteristics of fabric swaying in the wind are simulated efficiently and displayed vividly.

关键词： noise perlin noise fabric dynamic model

Evaluation of hydrodynamic dispersion parameters in fractured rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2010年第3期2卷 243-254页

作者： zhihong zhao Lanru Jing Ivars Neretnieks Department of Land and Water Resources Engineering Royal Institute of TechnologyStockholm SE-100 44Sweden Department of Chemical Engineering and Technology Royal Institute of TechnologyStockholm SE-100 44Sweden

A numerical procedure to determine the equivalent hydrodynamic dispersion coefficients and Péclet number（Pe） of a fractured rock is presented using random walk particle tracking *** geometrical effects of fracture system on hydrodynamic dispersion are *** results obtained from the proposed method agree well with those of empirical models,which are the scale-dependent hydrodynamic dispersion coefficients in an asymptotic or exponential form.A variance case is added to investigate the influence of longitudinal hydrodynamic dispersion in individual fractures on the macro-hydrodynamic dispersion at the fracture network scale,and its influence is demonstrated with a verification *** addition,we investigate the influences of directional flow and stress conditions on the behavior of hydrodynamic dispersion in fracture *** results show that the magnitudes of the hydrodynamic dispersion coefficients are relatively smaller when the flow direction is parallel to the dip directions of fracture *** stresses significantly reduce hydrodynamic ***,the remaining questions are：（1） whether the deformed fracture network under high stress conditions may make the scale-dependent hydrodynamic dispersion coefficients have asymptotic or exponential forms,and（2） what the conditions for existence of a well-defined equivalent hydrodynamic dispersion tensor *** need to be further investigated.

关键词： hydrodynamic dispersion Péclet number(Pe) fracture networks stress effects

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南京地铁苜蓿园站设计研究

铁道工程学报 2019年第8期36卷 79-84页

作者：赵志宏陕西省铁道及地下交通工程重点实验室

研究目的:南京地铁2号线苜蓿园站是进入南京中山陵园文化景区的门户车站,为解决以往地铁车站环境沉闷压抑、噪声大的问题,本站采用全新的地铁设计思路。本文重点对其进行建筑形式、结构分析、建筑消防、装修设计、声环境的分析和研究。... 详细信息

研究目的:南京地铁2号线苜蓿园站是进入南京中山陵园文化景区的门户车站,为解决以往地铁车站环境沉闷压抑、噪声大的问题,本站采用全新的地铁设计思路。本文重点对其进行建筑形式、结构分析、建筑消防、装修设计、声环境的分析和研究。研究结论:(1)调整车站规模、楼扶梯位置、柱网布置、车站层高等方式可以优化站厅公共区中庭的位置和范围,达到开敞通透的建筑效果;(2)中庭式车站侧墙应按单跨墙考虑,侧墙变形位移对柱的稳定性有影响;(3)调整结构尺寸,施工时将中板与侧墙整体浇筑可以保持结构整体性和分担弯矩;(4)型钢结构可有效减小结构构件尺寸;(5)增强站厅、站台公共区排烟系统能力,并对防排烟系统进行模拟分析和评估,可以解决设置中庭带来的建筑消防问题;(6)在装修设计中采用“爱情”这一人类永恒的主题贯穿其中,达到了美轮美奂的装修效果;(7)地铁车站内墙面和吊顶采用吸音材料能有效降低车站噪声;(8)车站内引入音乐能渲染气氛,声与景做到完美的融合;(9)本车站的设计研究成果可为其他同类型城市轨道交通车站设计要点和技术提供参考和探讨性意见。

关键词：地铁中庭建筑消防装修设计声环境

Flexible dual-Janus porous membrane for underwater gas bubbles anti-buoyancy unidirectional transportation

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Science China Chemistry 2024年

作者： Shuang Ben Han Ma Rui Liu Yuzhen Ning zhihong zhao Xudong Zhang Qiang Li Kesong Liu School of Materials Science and Engineering Shenyang Ligong University Tianmushan Laboratory School of Equipment Engineering Shenyang Ligong University Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology School of Chemistry Beihang University School of Mechanical Engineering and Automation Beihang University

Controllable transportation of bubbles in surfactant or aqueous is very important in daily chemical products, food fermentation,mineral flotation and other fields. However, bubbles are mainly dominated by buoyancy and move upward in solution, which makes the manipulation of bubbles difficult. Although some progress has been made in controlling underwater bubbles,achieving continuous transportation and collection of underwater bubbles without relying on external forces is still a great challenge. To this end, we bionically designed a flexible polydimethylsiloxane(PDMS) porous surface with dual-Janus characteristics. Namely, a porous PDMS membrane integrating structural gradient and wettability gradient realizes the underwater anti-buoyancy unidirectional transportation of bubbles without external force input, and possesses the capability of underwater gas anti-buoyancy transportation and storage. This work provides inspiration and direction for the development and design of underwater gas transportation and storage devices and provides innovative thinking for the implementation of seabed carbon dioxide storage technology.

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基于残差连接和1D-CNN的滚动轴承故障诊断研究

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振动与冲击 2021年第10期40卷 1-6页

作者：赵敬娇赵志宏杨绍普石家庄铁道大学信息科学与技术学院石家庄050043 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043

针对滚动轴承故障诊断人工提取特征困难、浅层诊断模型性能差的问题,提出一种基于残差连接的一维卷积神经网络(1D-CNN)的深层轴承故障诊断模型。将原始轴承振动信号输入网络中,利用具有残差连接的多个一维卷积层自动提取特征,残差连接... 详细信息

针对滚动轴承故障诊断人工提取特征困难、浅层诊断模型性能差的问题,提出一种基于残差连接的一维卷积神经网络(1D-CNN)的深层轴承故障诊断模型。将原始轴承振动信号输入网络中,利用具有残差连接的多个一维卷积层自动提取特征,残差连接能够在提取深层特征信息的同时将浅层提取的特征信息保留下来,与无残差连接的一维卷积网络相比能获得更丰富的轴承信号特征信息,并输入到Softmax层进行分类,输出轴承振动信号的故障类型。该研究通过不同残差网络结构模型的设计,验证具有残差连接的1D-CNN的网络模型在轴承故障诊断的有效性。试验结果表明,残差连接能有效提高轴承故障诊断的准确率。

关键词：一维卷积神经网络(1D-CNN) 残差连接轴承故障诊断