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Three-Dimensional Sound Propagation and Scattering in Two-Dimensional Waveguides

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Chinese Physics Letters 2013年第11期30卷 120-123页

作者： QIN Ji-Xing luo wen-yu ZHANG Ren-He YANG Chun-Mei State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

A coupled-mode method for three-dimensional acoustic propagation and scattering in two-dimensional waveguides is *** method synthesizes the three-dimensional field solution by using Fourier transform techniques based on a sequence of two-dimensional problems,each of which is solved by a numerical model recently developed by luo et al.[***.29(2012)014302].Numerical results indicate that the present model is remarkably accurate,and thus can serve as benchmark against other numerical *** addition,this model can be applied to realistic problems,and can also be used to analyze horizontal refraction in some range-dependent waveguides in reality,such as the continental shelf environment,ridge-like bathymetry,and underwater trenches.

关键词： trench scattering waveguides

Numerical Solution of Range-Dependent Acoustic Propagation

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Chinese Physics Letters 2013年第7期30卷 108-111页

The direct global matrix approach can be applied to modeling of range-dependent sound propagation in order to achieve numerically stable and accurate *** solving the global system directly,this method features high efficiency as well as accuracy by avoiding error *** is an important issue to solve linear systems numerically in the direct global matrix approach,especially for the large-scale *** efficient and memory-saving algorithm is developed for solving the global system,in which the global coefficient matrix is treated as a block pentadiagonal *** a result,this numerical model has the ability to solve large-scale problems on regular *** examples are also presented to demonstrate the accuracy and efficiency of this method.

关键词： problems. method. matrix.

Sound Propagation in a Wedge with a Rigid Bottom

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Chinese Physics Letters 2012年第10期29卷 89-92页

作者： luo wen-yu YANG Chun-Mei QIN Ji-Xing ZHANG Ren-He State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190 Graduate University of Chinese Academy of Sciences Beijing 100049

Sound propagation in a wedge with perfectly reflecting boundaries is one of the few range-dependent problems with an analytical *** sound propagation towards the wedge apex will be completely backscattered due to the perfectly reflecting boundaries,this test problem is an ideal benchmark for a full two-way solution to the wave *** analytical solution for sound propagation in a wedge with a pressure-release sea surface and a pressure-release bottom was presented by Buckingham et al.[***.87(1990)1511].The ideal wedge problem with a rigid bottom is also of great importance in underwater *** present an analytical solution to the problem with a wedge bounded above by a pressure-release sea surface and below by a rigid bottom,which may be used to provide informative means of investigating the sound field in depth-varying channels,and to establish the accuracy of numerical propagation models for which it is difficult to treat problems with a pressure-release bottom.A comparison of the analytical solution and the numerical solution recently proposed by luo et al.[***.29(2012)014302]is also presented,indicating that this numerical propagation model provides high accuracy.

关键词： equation solution wedge

Regional sea level change in Northwest Pacific： Process, characteristic and prediction

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Journal of Geographical Sciences 2011年第3期21卷 387-400页

作者： luo wen yuAN Linwang yu Zhaoyuan YI Lin XIE Zhiren Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210046 China

Based on 22 sparse-distributed tide gauge records in the Northwest Pacific Ocean marginal sea, the process, characteristic and prediction of regional sea level change are discussed by the integration of the following methods. Firstly, the regularized EM algorithm （RegEM） and the Multi-taper Spectral Method （MTM） are adopted to interpret their multiscale fluctuation processes and their spatial-temporal variations. Secondly, the orderly cluster method is introduced to classify these tidal stations, and with the consideration of the space adjacent relation, we obtain five sub-regions （the coasts of Bohai Sea-northern Yellow Sea, Yellow Sea-East China Sea along Chinese coast, the East China Sea along Japanese coast, the southern East China Sea and the northwestern South China Sea）. Furthermore, the Mean Generation Function （MGF） is explored to predict the medium- and long-term trends of each tide station. Finally, the Principal Component Analysis （PCA） is employed to obtain regional-scale sea level change trends, sea level rise rates of the above five sub-regions from 2001 to 2030 are 1.23-1.27 mm/a, 3.30-3.34 mm/a, 2.72-2.76 mm/a, 1.43-1.47 mm/a and 1.13-1.15 mm/a respectively, and the whole region sea level rise rate is between 2.01 mm/a and 2.11 mm/a. The aim of our work is to conduct an integrated research on regional sea level change.

关键词： regional sea level change spatial-temporal variation MTM prediction Northwest Pacific

Tilting homeostatic and dyshomeostatic microglial balance in health and disease:transforming growth factor-beta1 as a critical protagonist

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Neural Regeneration Research 2025年第10期20卷 2895-2897页

作者： Nicolas Hugues yu luo Department of Molecular and Cellular Biosciences University of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program University of CincinnatiCincinnatiOHUSA Division of Immunobiology Cincinnati Children’s Hospital Medical CenterUniversity of Cincinnati College of MedicineCincinnatiOHUSA

Adult microglia,by continuously sensing changes in their environment and communicating with nearly all brain cell types,are considered to be the immune sentinels of the *** the healthy central nervous system(CNS),microglia display a unique molecular homeostatic signature(i.e.,Tmem119,P2ry12,Sall1,Siglech,Gpr34,and Hexb)(Figure 1A).

关键词： Figure signature critical

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软件定义无线环境:技术、机遇与挑战

电子学报 2020年第9期48卷 1850-1859页

作者：罗文宇许丽邵霞华北水利水电大学物理与电子学院河南郑州450046

无线环境通常表示能够显著改变电磁波在通信设备之间传播的物体集合.软件定义无线环境允许针对不同通信设备以最适宜的方式进行电磁传播规律的编程定制,为无线通信的发展提供了一种新的视角.相比被动抑制无线信道影响的传统通信技术,软... 详细信息

无线环境通常表示能够显著改变电磁波在通信设备之间传播的物体集合.软件定义无线环境允许针对不同通信设备以最适宜的方式进行电磁传播规律的编程定制,为无线通信的发展提供了一种新的视角.相比被动抑制无线信道影响的传统通信技术,软件定义无线环境有着更高维度的调控自由度,在新一代移动通信特别是毫米波及太赫兹通信领域具有很大的应用潜力.本文首先介绍了软件定义无线环境的概念、历史沿革及其研究现状.然后给出了其基础模型及相对传统手段展现出来的性能优势.接着总结了软件定义无线环境的系统设计、网络服务支持、网络通信协议等关键技术,并指出软件定义无线环境未来发展所面临的挑战.最后凝练了几个面向新一代移动通信技术的软件定义无线环境研究方向.

关键词：软件定义无线环境可编程超表面超贴片无线协议

广义Navier-Stokes方程的正则性

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西南师范大学学报（自然科学版） 2010年第4期35卷 59-62页

作者：罗玉文重庆理工大学数学与统计学院

研究带分数次扩散项（-Δ）αu的广义三维Navier-Stokes方程（GNS）的正则性.采用能量积分方法,研究GNS方程的解用速度向量的分量来判定正则性,指出：如果u1/x3,u2/ux3∈Lp2（0,T;Lq2）或者ux12,u2/x1∈Lp2（0,T;Lq2）,... 详细信息

研究带分数次扩散项（-Δ）αu的广义三维Navier-Stokes方程（GNS）的正则性.采用能量积分方法,研究GNS方程的解用速度向量的分量来判定正则性,指出：如果u1/x3,u2/ux3∈Lp2（0,T;Lq2）或者ux12,u2/x1∈Lp2（0,T;Lq2）,且u3∈Lp1（0,T;Lq1）,其中2α/p1＋3/q1≤2α-1,2α/p2＋3/q2≤2α,那么方程在（0,T）上的光滑解在[0,T]上依然是光滑的.

关键词：广义Navier-Stokes方程组正则性 Lebesgue空间

Mesh-supported V2O5-WO3/TiO2 nanosheet array catalysts for efficient removal of NOx

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Tungsten 2025年第1期7卷 100-111页

作者： Zhi-Qi Zhang Liu Yang wen luo Vladimir An Jing Li Bao-Dan Liu School of Materials Science and Engineering Northeastern University Foshan Graduate School of Innovation Northeastern University Kizhner Research Center School of Advanced Manufacturing Technologies Tomsk Polytechnic University

The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas *** this study,we have developed a novel approach to fabricate highly efficient V2O5-WO3/TiO2monolithic mesh catalysts for NOxreduction at low ***,TiO2nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal ***,super-small traces of WO3and V2O5active nano-species were subsequently deposited on TiO2nanosheets using the deposition-precipitation *** to traditional ceramic-based V2O5-WO3/TiO2catalysts,our V2O5-WO3/TiO2monolithic mesh catalyst exhibits superior mechanical performance,excellent thermal conductivity,lower pressure drop,higher utilization of active components,and stronger synergistic ***,the V2O5-WO3/TiO2monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NOxconversion at 220℃,and remarkable long-term SO2tolerance and water resistance in the selective catalytic reduction（SCR） of NOxwith *** SCR reaction of tiny V2O5and WO3active species supported on TiO2nanosheets directly demonstrated to follow the Eley-Rideal mechanism by in situ infrared spectra.

关键词： Low temperature activity Monolithic mesh catalysts NH3-SCR SO2 tolerance V2O5-WO3/TiO2

An ultrahigh-voltage 4H-SiC merged Pi N Schottky diode with three-dimensional p-type buried layers

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Journal of Central South University 2021年第12期28卷 3694-3704页

作者： YANG Shuai ZHANG Xiao-dong CAO An luo wen-yu ZHANG Guang-lei PENG Bo ZHAO Jin-jin School of Electrical and Electronic Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Materials Science and Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Microelectronics Xidian UniversityXi'an 710071China

In the modern society,there is a strong demand for semiconductor chips,and the 4H polytype silicon carbide(4H-SiC)power device is a promising candidate for the next generation semiconductor chip,which can be used in various power electronic *** order to improve the performance of the 4H-SiC power device,a novel ultrahigh-voltage(UHV)4H-SiC merged p-type/intrinsic/n-type(PiN)Schottky(MPS)diode with three-dimensional(3D)p-type buried layers(PBL)(3D-PBL MPS)is proposed and investigated by numerical *** static forward conduction characteristics of the 3D-PBL MPS are similar to those of the conventional 4H-SiC MPS diode without the PBL(PBL-free MPS).However,when the 3D-PBL MPS is in the reverse blocking state,the 3D PBL can transfer the peak electric field(E_(peak))into a deeper position in the body of the epitaxial layer,and enhance the ability of the device to shield the high electric field at the Schottky contact interface(E_(S)),so that the reverse leakage current of the 3D-PBL MPS at 10 kV is only 0.002%of that of the PBL-free ***,the novel 3D-PBL MPS has overcome the disadvantage in the 4H-SiC MPS diode with the two-dimensional PBL(2D-PBL MPS),and the forward conduction characteristic of the 3D-PBL MPS will not get degenerated after the device converts from the reverse blocking state to the forward conduction state because of the special depletion layer variation mechanism depending on the 3D *** the simulation results show that the novel UHV 3D-PBL MPS has excellent device performance.

关键词： 4H polytype silicon carbide merged PiN Schottky diode power diode three dimensional