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Dissipation function in turbulent plane Poiseuille and Couette flows subject to spanwise rotations 预览
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作者 Zhenhua XIA Yipeng SHI +1 位作者 Qingdong CAI Jie GAI 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第2期185-192,共8页
The dissipation function in turbulent plane Poiseuille flows(PPFs)and plane Couette flows(PCFs)subject to spanwise rotations is analyzed.It is found that,in the PCFs without system rotations,the mean part is constant ... The dissipation function in turbulent plane Poiseuille flows(PPFs)and plane Couette flows(PCFs)subject to spanwise rotations is analyzed.It is found that,in the PCFs without system rotations,the mean part is constant while the fluctuation part follows a logarithmic law,resulting in a similar logarithmic skin friction law as PPFs.However,if the flow system rotates in the spanwise direction,no obvious dependence on the rotation number can be evaluated.In the PPFs with rotations,the dissipation function shows an increase with the rotation number,while in the PCFs with rotations,when the rotation number increases,the dissipation function first decreases and then increases. 展开更多
关键词 dissipation function spanwise rotation PLANE POISEUILLE flow(PPF) PLANE COUETTE flow(PCF)
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In-plane attenuation zone and its optimization in a plate with periodic holes
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作者 LIU Xiongwei HUANG Jiankun +2 位作者 HU Yucun LI Yaguang LIU Wen 《声学学报:英文版》 CSCD 2019年第1期85-98,共14页
It is difficult to design a plate with wide attenuation zones in low frequency region based on Bragg scattering mechanism.A plate with periodic rhombus holes is optimized and designed.Based on the finite element metho... It is difficult to design a plate with wide attenuation zones in low frequency region based on Bragg scattering mechanism.A plate with periodic rhombus holes is optimized and designed.Based on the finite element method under periodic boundary conditions,the in-plane dispersion curves of periodically perforated plate are calculated via COMSOL.The frequency responses of periodically perforated plate are investigated via ANSYS simulation.The plates with periodic holes are suspended and dynamically tested under sinusoidal excitations.The results show that a periodically perforated plate with rhombus holes has wider attenuation zones than plates with circular and hexagonal holes.Material properties have a great influence on attenuation zones:nitrile-butadiene rubber and silicon rubber can easily obtain low-frequency zones,while increasing porosity creates lower and wider zones.The width of attenuation zone increases as the horizontal angle of the rhombus holes increases.An analysis of the attenuation zones'generation mechanism shows that the plate with periodic holes exhibits characteristics of Bragg scattering and local resonant phononic crystal,indicating an inherent relationship between two types of mechanisms.The optimized plate has a complete attenuation zone ranging from 5281.76 -8824.30 Hz.The vibrations are significantly reduced when the number of periods is no less than two.The attenuation range obtained via the numerical method is generally consistent with the experiment.The research sheds light on the noise insulation plate and has the potential to improve the sound environment in various applications due to its simple manufacturing. 展开更多
关键词 IN-PLANE ATTENUATION ZONE PLATE with PERIODIC HOLES COMSOL
Analytic solution for a circular nano-inhomogeneity in a finite matrix 预览
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作者 Shuang Wang Zengtao Chen Cunfa Gao 《纳米材料科学(英文版)》 CAS 2019年第2期116-120,共5页
The Gurtin-Murdoch model has found wide applications in analyzing the mechanical behaviors of nanocomposites with surface/interface effect. In the existing literature, the matrix is usually assumed to be infinite and ... The Gurtin-Murdoch model has found wide applications in analyzing the mechanical behaviors of nanocomposites with surface/interface effect. In the existing literature, the matrix is usually assumed to be infinite and the surface/interface effect is considered only at the inhomogeneity-matrix interface. This assumption is indeed valid as the matrix is usually at macroscale rather than nanoscale. However, if the size of the matrix decreases to the nanoscale too, the surface/interface effect will have to be considered at the outer boundary of the matrix. In this paper, the plane deformation of a circular nano-inhomogeneity embedded inside a finite circular matrix (which implies the matrix is also at nanoscale) is investigated. The stress boundary conditions are given at the inhomogeneity-matrix interface and the outer boundary of the matrix by the G-M model. The analytic solution for the stress field is finally obtained through the complex variable method. The results show that the stress field inside the inhomogeneity is still uniform (size-dependent) when the surface/interface effect is considered. In addition, the stress field inside the bulk (including the inhomogeneity and the matrix) can be influenced not only by the size and elastic constant of the inhomogeneity, but also by those of the matrix. 展开更多
关键词 PLANE problem NANOSCALE INHOMOGENEITY FINITE MATRIX Surface/interface effect Complex variable methods
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Numerical investigation of plane Couette flow with weak spanwise rotation
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作者 YuHan Huang ZhenHua Xia +2 位作者 MinPing Wan YiPeng Shi ShiYi Chen 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第4期71-83,共13页
Direct numerical simulation of rotating plane Couette flow(RPCF) at Rew= 1300 and Ro = 0.02 was performed with different mesh resolutions and different sizes of computation domain. Our results showed that a grid resol... Direct numerical simulation of rotating plane Couette flow(RPCF) at Rew= 1300 and Ro = 0.02 was performed with different mesh resolutions and different sizes of computation domain. Our results showed that a grid resolution in wall units with △x^+=8.51,△z^+= 4.26,△y^+|min= 0.0873 and △y^+|max= 3.89 is fine enough to simulate the problem at the present parameters. The streamwise length Lxand spanwise length Lzof the computational box have different impacts on the flow statistics, where the statistics were converged if Lxis longer than 8πh, while no converged results were obtained for different Lz. More importantly,our results with very long simulation time showed that a state transition would happen if Lx≥ 8πh, from a state with four pairs of roll cells to a state with three pairs of roll cells with Lz= 6πh. Each state could survive for more than 1500 h/Uw, and the flow statistics were different. 展开更多
关键词 plane COUETTE flow SPAN WISE ROTATION state transition
Bonding Properties of Aluminum Alloy Plate and Concrete 预览
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作者 Haoran Wang 《智能建筑研究》 2019年第1期42-53,共12页
Aluminum alloy material has the advantages of high strength, good deformation performance, corrosion resistance, etc. it is an ideal material for steel reinforced concrete structure reinforcement engineering in coasta... Aluminum alloy material has the advantages of high strength, good deformation performance, corrosion resistance, etc. it is an ideal material for steel reinforced concrete structure reinforcement engineering in coastal erosion environment. The cohesive property of aluminum alloy plate and concrete is the key problem whether the aluminum alloy plate and steel bar concrete beam can work together. Based on this, the bonding performance between aluminum alloy plate and concrete is tested and theoretically studied. Considering the influence of strength of mixed concrete, width and thickness of aluminum alloy plate, bonding length and interface treatment on the bonding performance of aluminum alloy plate and concrete block, a set of specimen fixing device was designed, and 105 bonded specimens of aluminum alloy plate and mixed concrete prism were tested in-plane single shear by universal testing machine. According to the test results and theoretical analysis, the typical characteristics of cohesive failure, shear stress distribution curve and cohesive slip curve of aluminum alloy plate and mixed concrete are obtained. The research shows that there are two types of failure of the specimen: interfacial peeling failure and mixed concrete layer peeling failure. Interface treatment has an important influence on the bonding performance. The specimens without roughening the bonding interface have interface peeling and breaking, while other specimens have concrete layer peeling and breaking. As the strength of the mixed concrete increases and the width and thickness of the aluminum alloy plate decrease, the cohesiveness can be improved. There is an effective adhesive length. When the adhesive length is greater than the effective adhesive length, increasing the adhesive length does not increase the ultimate load of the connection. 展开更多
关键词 Aluminum alloy PLATE Adhesion property IN-PLANE single SHEAR test SHEAR stress STRIPPING failure
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Transferring in control plane for 5G heterogeneous networks 预览
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作者 毕瑞琪 Yang Ruizhe +2 位作者 Sun Yanhua Wang Zhuwei Zhang Yanhua 《高技术通讯:英文版》 CAS 2019年第3期271-276,共6页
The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load ... The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network. 展开更多
关键词 C/U SEPARATION 5G CONTROL PLANE OPTIMIZATION SIGNALING LOAD
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A Review of the Calculation Formula for the Four-component Borehole Strainmeter and Application to Earthquake Cases 预览
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作者 SU Kaizhi 《中国地震研究:英文版》 CSCD 2019年第1期132-146,共15页
Based on the principle formula for the four-component strainmeters, we can directly obtain the specific plane strain, shear strain and azimuthal angle of the principal strain, and the maximum and minimum principal str... Based on the principle formula for the four-component strainmeters, we can directly obtain the specific plane strain, shear strain and azimuthal angle of the principal strain, and the maximum and minimum principal strains calculated afterwards are the indirect result. The problems of practicality of the sensitivity coefficients A and B of plane strain and shear strain are then discussed. Based on this idea, we analyzed the observation data of several fourcomponent borehole strainmeters near the epicenter of the Yiliang MS5. 7 earthquake in 2012 and the Ludian MS6. 5 earthquake in 2014 in the Zhaotong area, Yunnan Province. The results show that the analysis based on the perspective of plane strain and shear strain has an obviously better effect than that based on the component readings, and can directly peel off the respective abnormality of the plane strain and shear strain. In addition, the correlation coefficient curves between measured data of two plane strains show significant anomalies which often occur several days before and during the earthquake. 展开更多
关键词 Four-component borehole strainmeter Ludian MS6. 5 EARTHQUAKE Yiliang MS5. 7 EARTHQUAKE Plane STRAIN ABNORMALITY Shear STRAIN ABNORMALITY SELF-TEST of data STRAIN anomaly
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激光加工平面型微超级电容器的研究进展与发展趋势
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作者 汤勇 刘辉龙 +5 位作者 陆龙生 谢颖熙 袁伟 万珍平 李宗涛 丁鑫锐 《机械工程学报》 EI CAS CSCD 北大核心 2019年第4期189-206,共18页
可穿戴和便携式电子设备朝“轻薄化”与“小型化”方向的快速发展,极大地刺激了现代社会对高能量/功率密度、轻量便携化、柔性化储能器件的强烈需求。平面型微超级电容器(In-plane micro-supercapacitors, IPMSC)作为一种新型的微电源... 可穿戴和便携式电子设备朝“轻薄化”与“小型化”方向的快速发展,极大地刺激了现代社会对高能量/功率密度、轻量便携化、柔性化储能器件的强烈需求。平面型微超级电容器(In-plane micro-supercapacitors, IPMSC)作为一种新型的微电源储能器件,以其超薄厚度、高功率密度和长循环寿命等优点被认为是集成电子器件重要的储能器件而备受关注。但是,随着IPMSC加工技术不断朝着高效、高精度和低成本等方向发展,常用的加工技术已难以满足其要求,操作更易、可扩展性更强、精度较高和成本更低的激光加工技术成为了目前IPMSC加工技术的研究热点。基于此,对不同类型IPMSC的工作原理及其电化学性能进行了总结,从激光还原、激光诱导、激光刻蚀和激光烧结四方面着手详细介绍了激光加工IPMSC的类型及加工工艺,重点综述了目前国内外关于激光加工IPMSC在机械性能和电化学性能等方面的研究进展情况,概括了用于IPMSC电解质的特性及其挑战,并在综合探讨激光加工IPMSC所面临的技术挑战基础上,对其在可穿戴和便携式电子设备中的应用前景进行了展望。 展开更多
关键词 微超级电容器 平面型 激光加工 储能器件
公务机客舱空间尺寸工效设计准则与验证 预览
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作者 郭菲 孙有朝 +1 位作者 郭媛媛 刘宇婕 《人类工效学》 2019年第3期37-41,共5页
目的 建立公务机客舱空间尺寸人机工效设计准则与验证程序。方法 基于CCAR/FAR/CS25部,给出了公务机客舱空间尺寸规章差异分析、准则生成方法、准则验证程序。评估了某型公务机客舱空间五项尺寸参数,遍历设计准则中可量化测量要求。结果... 目的 建立公务机客舱空间尺寸人机工效设计准则与验证程序。方法 基于CCAR/FAR/CS25部,给出了公务机客舱空间尺寸规章差异分析、准则生成方法、准则验证程序。评估了某型公务机客舱空间五项尺寸参数,遍历设计准则中可量化测量要求。结果 空间尺寸设计准则有利于优化公务机客舱人机工效、提升用户体验。结论 提出的客舱尺寸工效设计准则和验证程序,保证了公务机客舱人机工效设计的正确性和合理性。 展开更多
关键词 工业工程 产品设计 公务机 适航 客舱环境 人机工效设计 民航 飞机
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Obstacle Avoidance Method for a Redundant Manipulator Based on a Configuration Plane 预览
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作者 Yanhui Wei Yanfeng Zhao +4 位作者 Jing Liu Shenggong Hao Lixue Xu Qiang Zhu Anqi Wang 《北京理工大学学报:英文版》 EI CAS 2019年第3期456-468,共13页
This paper presents a novel approach of obstacle avoidance for redundant manipulators, which is challenging with the considerations of the building of universal kinematics, the formation of dynamics, and the generatio... This paper presents a novel approach of obstacle avoidance for redundant manipulators, which is challenging with the considerations of the building of universal kinematics, the formation of dynamics, and the generation of trajectories. A universal approach to deal with obstacle avoidance for the redundant manipulator, that is based on the configuration plane, is presented. The paper also examines common serial robot configurations and introduces a method for classification, partitioning, simplification, and forms of expression used in the workspace to define the configuration plane. This relatively new method is combined with a weighted space vector method to match the configuration plane and solve the inverse kinematics problem. The proposed planner is demonstrated with examples, in which the proposed planner is shown to be capable of providing a smoother trajectory. 展开更多
关键词 REDUNDANT manipulator CONFIGURATION PLANE trajectory generation OBSTACLE AVOIDANCE space vector
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Distance Between α-Orientations of Plane Graphs by Facial Cycle Reversals
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作者 Wei Juan ZHANG Jian Guo QIAN Fu Ji ZHANG 《数学学报:英文版》 SCIE CSCD 2019年第4期569-576,共8页
Cycle reversal had been shown as a powerful method to deal with the relation among orientations of a graph since it preserves the out-degree of each vertex and the connectivity of the orientations. A facial cycle reve... Cycle reversal had been shown as a powerful method to deal with the relation among orientations of a graph since it preserves the out-degree of each vertex and the connectivity of the orientations. A facial cycle reversal on an orientation of a plane graph is an operation that reverses all the directions of the edges of a directed facial cycle. An orientation of a graph is called an α-orientation if each vertex admits a prescribed out-degree. In this paper, we give an explicit formula for the minimum number of the facial cycle reversals needed to transform one α-orientation into another for plane graphs. 展开更多
关键词 α-Orientation FACIAL CYCLE REVERSAL DISTANCE plane graph
Threshold and decay properties of transient isolated turbulent band in plane Couette flow 预览
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作者 Jianzhou LU Jianjun TAO +1 位作者 Weitao ZHOU Xiangming XIONG 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第10期1449-1456,共8页
By direct numerical simulations of the plane Couette flow (PCF) in a large computational domain, it is shown that an isolated turbulent band decays monotonically at low Reynolds numbers but experiences transient growt... By direct numerical simulations of the plane Couette flow (PCF) in a large computational domain, it is shown that an isolated turbulent band decays monotonically at low Reynolds numbers but experiences transient growth before the eventual relaminarization at moderate Reynolds numbers. The lower bound Reynolds number of the transient-growth regime is determined as 286. The width, length, and tilt angle of the iso- lated band structure are defined based on the disturbance kinetic energy in the mid-plane, and the geometric characteristics of the band can be described with a tilted rectangle. It is illustrated that before its eventual fragmentation, the isolated turbulent band decays in a style of longitudinal contraction, where the center, width, and tilt angle of the band keep almost constant but the band length contracts with a statistically constant velocity. 展开更多
关键词 plane COUETTE flow (PCF) SUBCRITICAL transition TURBULENT BAND
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基于特征单元的三角形蜂窝异面压缩的有限元分析 预览
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作者 孙德强 李钟波 +4 位作者 李国志 段世非 白家华 张帆 李清 《包装工程》 CAS 北大核心 2019年第19期80-85,共6页
目的研究三角形蜂窝排列方式对三角形蜂窝异面动态压缩性能的影响。方法借助Ansys/LS-DYNA建立基于特征单元的三角形蜂窝异面动态压缩的有限元分析模型,研究三角形蜂窝排列方式对三角形蜂窝异面压缩性能的影响。结果将三角形蜂窝胞元阵... 目的研究三角形蜂窝排列方式对三角形蜂窝异面动态压缩性能的影响。方法借助Ansys/LS-DYNA建立基于特征单元的三角形蜂窝异面动态压缩的有限元分析模型,研究三角形蜂窝排列方式对三角形蜂窝异面压缩性能的影响。结果将三角形蜂窝胞元阵列模型的有限元分析结果与理论值进行对比,证明三角形蜂窝的有限元模型是可靠的,随后将三角形胞元阵列模型与此研究中采用的特征单元模型计算结果进行对比,结果显示2种有限元计算模型的计算结果一致,证明此研究特征单元结构的选取和模型的建立是可靠的。结论不同排列方式对三角形蜂窝在异面方向上的动态峰应力和单位体积能量吸收没有影响。 展开更多
关键词 三角形蜂窝 有限元分析 压缩性能 异面
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基于平面视角下不同文化背景的城市形态研究 预览
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作者 何丹秋 《城市建筑》 2019年第14期97-98,共2页
本文从平面的角度对唐长安城与古罗马城进行分析,审视两者间形态上的差异,从而反映出不同文化背景影响下所产生的城市形态,为国内城市规划及建筑设计提供理论依据。同时对城市平面布局、城市院落与广场、城市街巷空间及城市主要建筑形... 本文从平面的角度对唐长安城与古罗马城进行分析,审视两者间形态上的差异,从而反映出不同文化背景影响下所产生的城市形态,为国内城市规划及建筑设计提供理论依据。同时对城市平面布局、城市院落与广场、城市街巷空间及城市主要建筑形式等方面的平面形态进行分析,对比东西方城市形态的差异,探讨不同文化背景对于平面形态的影响,得出国内发展特点并吸取国外的设计经验。 展开更多
关键词 城市形态 平面 文化背景 唐长安城 罗马古城
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淠史杭灌区水资源配置与调度实践 预览
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作者 朱红 《中国水利》 2019年第3期16-18,共3页
安徽省淠史杭灌区自建成运行以来,建立形成了一套符合灌区水资源特点、以“统一调度、计划供水、总量控制、综合利用”为主要特征的水资源配置与供水调度体系,取得了明显的灌溉供水和抗旱减灾效益,为区域经济社会发展、灌区粮食稳产、... 安徽省淠史杭灌区自建成运行以来,建立形成了一套符合灌区水资源特点、以“统一调度、计划供水、总量控制、综合利用”为主要特征的水资源配置与供水调度体系,取得了明显的灌溉供水和抗旱减灾效益,为区域经济社会发展、灌区粮食稳产、城镇居民生活、生态环境改善等提供了安全可靠的水资源保障。 展开更多
关键词 淠史杭灌区 水资源配置 供水调度 成效
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集中荷载作用下FRP圆弧拱的面内非线性弹性失稳研究 预览
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作者 张紫祥 刘爱荣 钟子林 《西安建筑科技大学学报:自然科学版》 北大核心 2019年第2期230-234,258共6页
本文开展了集中荷载作用下FRP圆弧拱的面内弹性失稳理论研究,基于能量变分原理建立了拱的非线性平衡方程,提出了FRP拱修正长细比计算公式,推导了拱失稳临界荷载解析解.通过有限元数值解验证了理论公式的正确性,着重分析了铺层角度、铺... 本文开展了集中荷载作用下FRP圆弧拱的面内弹性失稳理论研究,基于能量变分原理建立了拱的非线性平衡方程,提出了FRP拱修正长细比计算公式,推导了拱失稳临界荷载解析解.通过有限元数值解验证了理论公式的正确性,着重分析了铺层角度、铺层厚度及矢跨比等设计参数对FRP拱失稳临界荷载的影响.研究结果表明,铺层方向显著影响拱的失稳临界荷载;对于单种角度铺层的截面,保证铺层总厚度不变条件下,仅增加铺层数量并不会引起失稳临界荷载量值的变化;拱矢跨比在1/10~1/3范围内变化时,失稳临界荷载随着矢跨比的增大而增大,且随着矢跨比的增加,增长速率逐渐下降. 展开更多
关键词 FRP 圆弧拱 面内 非线性屈曲 解析解
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上海崇明地区河道生态治理初探 预览 被引量:1
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作者 李念斌 黄蒙 许瑞东 《中国水利》 2019年第3期33-34,共2页
推进崇明世界级生态岛建设,需结合实际,因地制宜制定方案,不断探索新理念、新工艺、新材料,构建良好的水环境。指出了河道生态治理的误区,结合崇明地区河道现状,结合实例,从平面布局、断面设计、护岸结构等方面对生态河道治理中应当遵... 推进崇明世界级生态岛建设,需结合实际,因地制宜制定方案,不断探索新理念、新工艺、新材料,构建良好的水环境。指出了河道生态治理的误区,结合崇明地区河道现状,结合实例,从平面布局、断面设计、护岸结构等方面对生态河道治理中应当遵循的设计思路进行了探讨。通过河道疏浚、护岸建设以及绿化改造,打造自然生态景观,为崇明区生态河道治理提供参考。 展开更多
关键词 崇明 生态岛 平面 断面 护岸 生态河道
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巧用构造法解线性代数题 预览
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作者 王勇茂 《高等数学研究》 2019年第1期60-61,共2页
本文总结了使用构造法解线性代数题目的技巧,通过举例阐述了该方法在线性代数课程不同章节中的使用.
关键词 构造法 行列式 矩阵 方程组 平面欧氏空间
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Design and Analysis of 2D Photonic Crystal Based Biosensor to Detect Different Blood Components
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作者 Rajendran ARUNKUMAR Thinakaran SUAGANYA Savarimuthu ROBINSON 《光子传感器:英文版》 EI CAS CSCD 2019年第1期69-77,共9页
In this paper,a photonic crystal ring resonator based bio sensor is designed to sense different blood constituents in blood in the wavelength range of 1530nm-1615nm for biomedical applications.The blood constituents s... In this paper,a photonic crystal ring resonator based bio sensor is designed to sense different blood constituents in blood in the wavelength range of 1530nm-1615nm for biomedical applications.The blood constituents such as hemoglobin white blood cell,red blood cell,blood sugar, blood urea,albumin,serum bilirubin direct,and ammonia are sensed for the corresponding transmission output power,Q factor,and refractive index changes.As the blood constituent has unique,refractive index,the resonant wavelength and output power are varied from one to another, which are used to identify the blood constituents. 展开更多
关键词 PHOTONIC crystal PLANE wave expansion(PWE) finite difference time domain(FDTD) BIOSENSOR blood components
Terahertz emission from layered GaTe crystal due to surface lattice reorganization and in-plane noncubic mobility anisotropy
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作者 Jiangpeng Dong Kevin-P. Gradwohl +5 位作者 Yadong Xu Tao Wang Binbin Zhang Bao Xiao Christian Teichert Wanqi Jie 《光子学研究:英文版》 CSCD 2019年第5期518-525,共8页
In this work, a model based on the optical rectification effect and the photocurrent surge effect is proposed to describe the terahertz emission mechanism of the layered GaTe crystal. As a centrosymmetric crystal, the... In this work, a model based on the optical rectification effect and the photocurrent surge effect is proposed to describe the terahertz emission mechanism of the layered GaTe crystal. As a centrosymmetric crystal, the optical rectification effect arises from the breaking of the inversion symmetry due to lattice reorganization of the crystal’s surface layer. In addition, the photocurrent surge originating from the unidirectional charge carrier diffusion-due to the noncubic mobility anisotropy within the layers-produces terahertz radiation. This is confirmed by both terahertz emission spectroscopy and electric property characterization. The current surge perpendicular to the layers also makes an important contribution to the terahertz radiation, which is consistent with its incident angle dependence. Based on our results, we infer that the contribution of optical rectification changes from 90%under normal incidence to 23% under a 40° incidence angle. The results not only demonstrate the terahertz radiation properties of layered GaTe bulk crystals, but also promise the potential application of terahertz emission spectroscopy for characterizing the surface properties of layered materials. 展开更多
关键词 GATE CRYSTAL surface lattice REORGANIZATION IN-PLANE noncubic MOBILITY
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