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Long-Term Statistics of Extreme Tsunami Height at Crescent City

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Journal of Ocean University of China 2017年第3期16卷 437-446页

作者： DONG sheng ZHAI Jinjin tao Shanshan College of Engineering Ocean University of ChinaQingdao 266100P.R.China

Historically, Crescent City is one of the most vulnerable communities impacted by tsunamis along the west coast of the United States, largely attributed to its offshore geography. Trans-ocean tsunamis usually produce large wave runup at Crescent Harbor resulting in catastrophic damages, property loss and human death. How to determine the return values of tsunami height using relatively short-term observation data is of great significance to assess the tsunami hazards and improve engineering design along the coast of Crescent City. In the present study, the extreme tsunami heights observed along the coast of Crescent City from 1938 to 2015 are fitted using six different probabilistic distributions, namely, the Gumbel distribution, the Weibull distribution, the maximum entropy distribution, the lognormal distribution, the generalized extreme value distribution and the generalized Pareto distribution. The maximum likelihood method is applied to estimate the parameters of all above distributions. Both Kolmogorov-Smirnov test and root mean square error method are utilized for goodness-of-fit test and the better fitting distribution is selected. Assuming that the occurrence frequency of tsunami in each year follows the Poisson distribution, the Poisson compound extreme value distribution can be used to fit the annual maximum tsunami amplitude, and then the point and interval estimations of return tsunami heights are calculated for structural design. The results show that the Poisson compound extreme value distribution fits tsunami heights very well and is suitable to determine the return tsunami heights for coastal disaster prevention.

关键词： earthquake tsunami maximum tsunami height interval estimation Poisson compound distribution retum period

Aggregation and fragmentation of agglomerates in a fluidized bed of mixed nanoparticles by adding FCC coarse particles

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2531-2536页

作者： Hongbing mo Bao Xu Chuanbao Luo tao Zhou Jiangrong Kong Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources College of Chemistry and Chemical Engineering Central South University

In this study, the influence of fluid cracking catalyst(FCC) on the fluidization behavior of ZnO-CuO binary nanoparticles was systematically investigated by varying FCC size. High-speed camera was employed to analyze the collision and fragmentation process of agglomerates with adding FCC coarse particles. It can be found from photographs by the camera that fluidization performance improved by the agglomerate variation that is bound to be shaped a compact and spherical structure. Furthermore, the result of agglomeration composition analysis showed that uniform mixing of nanoparticles remarkably affected the fluidization behavior of ZnO-CuO binary system. Finally, the improvement of fluidization performance can be justified by the analysis of inter-cohesive force between the two agglomerates with sharp reduction of the newly-formed agglomerates.

关键词： Nanoparticles Fluidization Agglomerate Breakup

VA族元素修饰对二维AlN电磁性质调控的理论研究

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原子与分子物理学报 2025年第6期42卷 159-166页

作者：莫秋燕陈广萍张颂荆涛吴家隐凯里学院大数据工程学院凯里556011 凯里学院理学院凯里556011 广东开放大学(广东理工职业学院)工程技术学院广州510091

采用基于密度泛函理论的第一性原理计算方法,研究了VA族元素(N、P、As、Sb、Bi)对二维AlN电磁性质的影响.研究发现,VA族元素修饰后,二维AlN的能带结构发生显著劈裂,表明体系转变为磁性材料.同时,导带底部向低能量区域移动,使得二维AlN... 详细信息

采用基于密度泛函理论的第一性原理计算方法,研究了VA族元素(N、P、As、Sb、Bi)对二维AlN电磁性质的影响.研究发现,VA族元素修饰后,二维AlN的能带结构发生显著劈裂,表明体系转变为磁性材料.同时,导带底部向低能量区域移动,使得二维AlN的吸收阈值从紫外线区域扩展至可见光区域.因此,VA族元素的修饰显著调控了二维AlN的电子结构和磁性,为实现可见光响应的光电子和自旋电子器件提供了新思路和可能性.

关键词：二维AlN 第一性原理修饰电子结构

Autonomous Domain Correlation-Based Cross-domain Network View Caching Method for SDN Distributed Controller

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Chinese Journal of Electronics 2016年第6期25卷 1127-1133页

作者： FU tao HU Liang CHAI sheng CHE Xilong College of Computer Science and Technology Jilin University Key Laboratory of Symbolic Computing and Knowledge Engineering of Ministry of Education Jilin University

Software-defined networks(SDN) maintain a global view of the network, thus improving the intelligence of forwarding decisions. With the expansion of the network scale, distributed controllers are used in a variety of large-scale networks in which subnetworks managed by controller instance are called autonomous domains. We analyze statistic frequency of communication across the autonomous domain. We calculate the autonomous domain correlations for controller instances using acquired statistical information. We cache network views to highly correlated controller instances. Distributed controllers are capable of considering both the average response time and overall storage. An experiment shows that our method can fully take advantage of these two performance indicators.

关键词： Software-defined networks(SDN) Distributed controller Network analyze Network view cache

Temperature dependent Grüneisen parameter

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Science China(Technological Sciences) 2019年第9期62卷 1565-1576页

作者： ZHANG Xun SUN sheng XU tao ZHANG TongYi Materials Genome Institute Shanghai University

Grüneisen parameter is one of the most valuable quantities in thermodynamics, which links the material properties of bulk modulus, heat capacity at constant volume, thermal expansion coefficient, and volume together. A new thermodynamic model of temperature-dependent potential energy is proposed here to investigate the temperature dependent Grüneisen parameter of bulk material. The newly developed thermodynamic model leads to temperature dependent analytical solutions of Grüneisen parameter and other thermo-mechanical properties including the Grüneisen equation of state. molecular dynamics simulations are conducted on single crystalline Ni, Cu, and Au bulk crystals and the simulation results verify the newly developed thermodynamic model and quantitively evaluate the theoretically derived physical quantities. In addition, the Debye model is also employed in the study of temperature dependent Grüneisen parameter and the results also verify the theoretical approach.

关键词： thermo-mechanical properties Grüneisen parameter thermodynamic model temperature-dependent potential energy molecular dynamics simulations

Dynamical separation of rigid bodies in supersonic flow

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Science China(Technological Sciences) 2015年第12期58卷 2110-2121页

作者： LI tao SUI JingXia GONG sheng WU ChuiJie School of aeronautics and astronautics Dalian university of technology School of energy and power engineering Dalian university of technology

A computational investigation of the unsteady separation behavior of rigid bodies in Mach-4 flow is carried out. Two rigid bodies, a sphere and a cube, initially stationary, centroid axially aligned, are released and thereafter fly freely according to the aerodynamic forces experienced. During the separation process, the smaller cube can experience different types of movement and our principal interest here is the non-dimensional transverse velocity of it. The separation behavior is investigated for interactions between a sphere and a cube with different mass ratio and a constant initial distance between them. The qualitative separation behavior and the final transverse velocity of the small body are found to vary strongly with the mass ratio but less sensitive to the initial distance between the two bodies. At a critical mass ratio for a given distance, the smaller body transit from entrainment within the flow region bounded by the larger body's shock to expulsion and the accumulated transverse velocity of the small body is close to maximum. This phenomenon is the so-called ‘shock-wave surfing' phenomenon noted by Laurence & Deiterding for two spheres at hypersonic Mach numbers. Then we investigate the separation behavior of a sphere interaction with a rotary cube and with a non-rotary cube for a given mass ratio and different distance between them. The rotary is found to increase the likelihood of ‘surfing'. Only at a certain initial distance for a given mass ratio the rotary effect of cube can be neglectable.

关键词： separation behavior flow-structure interactions shock waves

Analysis and Optimization of a Spatial Parallel Mechanism for a New 5-DOF Hybrid Serial-Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 60-68页

作者： Dong-sheng Zhang Yun-Dou Xu Jian-tao Yao Yong-sheng Zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University

Hybrid manipulators have potentially application in machining industries and attract extensive attention from many researchers on the basis of high sti ness and high dexterity. Therefore,in order to expand the application prospects of hybrid manipulator,a novel 5?degree?of?freedom(DOF) hybrid serial?parallel manipulator(HSPM) is proposed. Firstly,the design plan of this manipulator is introduced. Secondly,the analysis of this manipulator is carried out in detail,including kinematics analysis,statics analysis,and workspace analysis. Especially,an amplitude equivalent method of disposing the over?constrained force/couple to the non?overconstrained force/couple is used in the statics analysis. Then,three performance indices are used to optimize the PM. Two of them have been widely used,and the third one is a new index which considers the characteristics of the actuated force. Based on the performance indices,the performance atlas is drawn and the optimal design of the PM is investigated. In order to satisfy the anticipant kinetic characteristics of the PM,the verification of the optimized physical dimension is done and the workspace based on the optimized physical dimension is carried out. This paper will lay good theoretical foundations for application of this novel HSPM and also can be applied to other hybrid manipulators.

关键词： Parallel mechanism Performance indices Optimal design Performance atlas

Group Sparsity Residual Constraint Image Denoising model with l_(1)/l_(2)Regularization

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Wuhan University Journal of Natural Sciences 2023年第1期28卷 53-60页

作者： WU Di ZHANG tao mo Xutao Key Laboratory of Multidisciplinary Management and Control of Complex Systems of Anhui Higher Education Institutes Anhui University of TechnologyMaanshan 243002AnhuiChina School of Mathematics and Physics Anhui University of TechnologyMaanshan 243032AnhuiChina

Group sparse residual constraint with non-local priors(GSRC)has achieved great success in image restoration producing stateof-the-art *** the GSRC model,the l_(1)norm minimization is employed to reduce the group sparse *** recent years,nonconvex regularization terms have been widely used in image denoising problems,which have achieved better results in denoising than convex regularization *** this paper,we use the ratio of the l_(1)and l_(2)norm instead of the l_(1)norm to propose a new image denoising model,i.e.,a group sparse residual constraint model with l_(1)/l_(2)minimization(GSRC-l_(1)/l_(2)).Due to the computational difficulties arisen from the non-convexity and non-linearity,we focus on a constrained optimization problem that can be solved by alternative direction method of multipliers(ADMM).Experimental results of image denoising show that the pro-posed model outperforms several state-of-the-art image denoising methods both visually and quantitatively.

关键词： image denoising l_(1)/l_(2)minimization group sparse representation

Synergistic effect of TiO_2 hierarchical submicrospheres for high performance dye-sensitized solar cells

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Science China Chemistry 2017年第6期60卷 822-828页

作者： Jiang sheng Linhua Hu Li'e mo Jichun Ye Songyuan Dai Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Key Laboratory of Novel Thin Film Solar Cells Institute of Applied Technology Chinese Academy of Sciences State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

The performance of dye-sensitized solar cells(DSCs) could be improved by using rationally designed mesoporous film structure for electron collection, dye adsorption and light scattering. The development of a novel double layer film prepared by TiO_2 hierarchical submicrospheres and nanoparticles was reported in this article. The submicrospheres were composed of rutile nanorods of 10 nm diameter and the length of 150–250 nm, which facilitated fast electron transport, charge collection and light scattering. Using a double layer structure consisting of the 10 wt% film as a dye loading layer and the 50 wt% film as the light scattering layer, C101 sensitizer and liquid electrolyte, DSC yielded power conversion efficiency of 9.68% under 1 sun illumination.

关键词： dye-sensitized solar cells rutile hierarchical submicrospheres high light harvesting high electron collection efficiency