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Economical Optimization of Grid Power Factor Using Predictive Data

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 258-267页

作者： Chaojiong Huang jason gu Haiying Liu Yuansheng Lu Jun Luo IEEE the School of Electrical Engineering and Automation Shanghai University the Department of Electrical and Computer Engineering Dalhousie University

We present an electrical grid optimization method for economical benefit. After simplifying an IEEE feeder diagram, we build a compact smart grid system including a photovoltaic-inverter system, a shunt capacitor, an on-load tapchanger(OLTC) and transmission lines. The system power factor(PF) regulation and reactive power dispatching are indispensable to improve power quality. Our control method uses predictive weather and load data to decide engaging or tripping the shunt capacitor, or reactive power injection by the photovoltaic-inverter system, ultimately to keep the system PF in a good range. From the perspective of economics, the economical model is considered as a decision maker in our predictive data control ***-only control strategy is a common photovoltaic(PV)regulation method, which is treated as a baseline case. Simulations with GridLAB-D on profiled loads and residential loads have been carried out. The comparison results with baseline control strategy and our predictive data control method show the appreciable economical benefit of our method.

关键词： Grid optimization GridLAB-D inverter power factor predictive data control shunt capacitor

A Composite State Convergence Scheme for Bilateral Teleoperation Systems

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IEEE/CAA Journal of Automatica Sinica 2019年第5期6卷 1166-1178页

作者： Muhammad Usman Asad Umar Farooq jason gu Ghulam Abbas Rong Liu Valentina E.Balas the Department of Electrical &Computer Engineering Dalhousie UniversityN.S.Canada the Department of Electrical & Computer Engineering Dalhousie UniversityN.S.Canada the Department of Electrical Engineering University of the Punjab LahorePakistan the Department of Electrical Engineering The University of LahorePakistan the Department of Biomedical Engineering Dalian University of TechnologyChina the Department of Automatics &Applied Software “Aurel Vlaicu” University of AradRomania

State convergence is a novel control algorithm for bilateral teleoperation of robotic systems. First, it models the teleoperation system on state space and considers all the possible interactions between the master and slave systems. Second, it presents an elegant design procedure which requires a set of equations to be solved in order to compute the control gains of the bilateral loop. These design conditions are obtained by turning the master-slave error into an autonomous system and imposing the desired dynamic behavior of the teleoperation system. Resultantly, the convergence of master and slave states is achieved in a well-defined manner. The present study aims at achieving a similar convergence behavior offered by state convergence controller while reducing the number of variables sent across the communication channel. The proposal suggests transmitting composite master and slave variables instead of full master and slave states while keeping the operator's force channel intact. We show that,with these composite and force variables;it is indeed possible to achieve the convergence of states in a desired way by strictly following the method of state convergence. The proposal leads to a reduced complexity state convergence algorithm which is termed as composite state convergence controller. In order to validate the proposed scheme in the absence and presence of communication time delays, MATLAB simulations and semi-real time experiments are performed on a single degree-of-freedom teleoperation system.

关键词： Composite variables linear control systems state convergence teleoperation time delay

Multi-objective optimization of process parameters for ultra-narrow gap welding based on Universal Kriging and NSGA Ⅱ

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China Welding 2023年第3期32卷 28-35页

作者：马生明张爱华顾建军漆宇晟马晶王平 College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Electrical and Computer Engineering Dalhousie UniversityHalifaxNSB3J 2X4 Canada

The successful confinement of the arc by the flux band depends on the welding process parameters for achieving single-pass,multi-layer, and ultra-narrow gap welding. The sidewall fusion depth, the width of the heat-affected zone, and the line energy are utilized as comprehensive indications of the quality of the welded joint. In order to achieve well fusion and reduce the heat input to the base *** welding process characteristics were chosen as the primary determinants, including welding voltage, welding speed, and wire feeding speed. The metamodel of the welding quality index was built by the orthogonal experiments. The metamodel and NSGA-Ⅱ(Non-dominated sorting genetic algorithm Ⅱ) were combined to develop a multi-objective optimization model of ultra-narrow gap welding process parameters. The results showed that the optimized welding process parameters can increase the sidewall fusion depth, reduce the width of the heataffected zone and the line energy, and to some extent improve the overall quality of the ultra-narrow gap welding process.

关键词： ultra-narrow gap optimization of process parameters non-dominated sorting genetic algorithm II the sidewall fusion depth

SDN网络中基于联合熵与多重聚类的DDoS攻击检测

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信息网络安全 2023年第10期 1-7页

作者：王智张浩顾建军福州大学计算机与大数据学院福州350116 福建省网络计算与智能信息处理重点实验室福州350116 达尔豪斯大学电气与计算机工程学院哈利法克斯B3J1Z1

软件定义网络(Software Defined Networking,SDN)作为一种新兴的网络范式,在带来便利性的同时也引入了更为严峻的分布式拒绝服务攻击(Distributed Denial of Service Attacks,DDoS)风险。现有的模型通常是使用机器学习模型来检测DDoS攻... 详细信息

软件定义网络(Software Defined Networking,SDN)作为一种新兴的网络范式,在带来便利性的同时也引入了更为严峻的分布式拒绝服务攻击(Distributed Denial of Service Attacks,DDoS)风险。现有的模型通常是使用机器学习模型来检测DDoS攻击,忽略了模型给SDN控制器带来的额外开销。为了更加高效且精确地检测DDoS攻击,文章采取了多级检测模块的方式,即一级模块通过计算当前流量窗口的联合熵快速检测异常,二级模块采用半监督模型,并使用特征选择、multi-training算法、多重聚类等技术,通过训练多个局部模型提高检测性能。与现有的其他模型相比,该模型在多个数据集上均表现更好,拥有更好的检测精度和泛化能力。

关键词：软件定义网络分布式拒绝服务攻击半监督学习统计学习

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移动心电监护系统的心电图实时分析算法

计算机仿真 2014年第9期31卷 272-276页

作者：郭文灵顾建军河南科技大学信息工程学院河南洛阳471023

在移动心电监护系统中,心电图中QRS波群的实时检测以及心律失常分析是至关重要的问题。针对这一问题,首先采用Pan-Tompkins算法检测QRS波,区分正常心电信号和心律失常,然后采用基于粗粒化过程的Lempel-Ziv(LZ)复杂度算法对心律失常进行... 详细信息

在移动心电监护系统中,心电图中QRS波群的实时检测以及心律失常分析是至关重要的问题。针对这一问题,首先采用Pan-Tompkins算法检测QRS波,区分正常心电信号和心律失常,然后采用基于粗粒化过程的Lempel-Ziv(LZ)复杂度算法对心律失常进行分析。通过对MIT-BIH数据库中的100条正常心电信号、120条心动过速信号和60条心室颤动信号进行仿真测试,结果表明该算法能够克服各种噪声对心电信号的影响,实现QRS波的精准检测,而且基于K-Mean粗粒化过程的LZ复杂度算法可以有效分离心动过速和心室颤动,是一种分析心律失常比较实用的方法。

关键词：移动心电监护心律失常分析粗粒化过程复杂度算法

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基于均值距离测度的医学图像配准(英文)

光子学报 2008年第5期37卷 1046-1051页

作者：杨金宝刘常春胡顺波顾建军山东大学控制科学与工程学院山东济南250061 临沂师范学院物理系山东临沂276005 达尔豪西大学电气与计算机工程系加拿大哈利法克斯

针对互信息测度在配准医学图像时易陷入局部极值、速度慢的缺点,提出了基于均值不等式的均值距离测度.首先根据均值不等式推导出5种均值距离测度:方根-算术均值距离(SAM)、方根-几何均值距离(SGM)、方根-调和均值距离(SHM)、算术-几何... 详细信息

针对互信息测度在配准医学图像时易陷入局部极值、速度慢的缺点,提出了基于均值不等式的均值距离测度.首先根据均值不等式推导出5种均值距离测度:方根-算术均值距离(SAM)、方根-几何均值距离(SGM)、方根-调和均值距离(SHM)、算术-几何均值距离(AGM)、算术-调和均值距离(AHM).然后通过人体脑部CT/MR和MR-T1/PD图像的刚体配准实验,从函数曲线、配准精度、计算时间和收敛性能方面,对互信息与5种均值距离信息测度进行了比较与分析.实验结果表明,在不损失配准精度的前提下,AHM和SAM测度可以获得更快的配准速度,对噪声有很强的鲁棒性.

关键词：图像配准相似性测度互信息均值距离

Pumping and sliding of droplets steered by a hydrogel pattern for atmospheric water harvesting

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National Science Review 2023年第12期10卷 181-192页

作者： Wei Zhang Qinghua Ji Gong Zhang Zhenao gu Haozhi Wang Chengzhi Hu Huijuan Liu Zhiyong jason Ren Jiuhui Qu Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of Environment Tsinghua University Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Joint School of National University of Singapore and Tianjin University International Campus of Tianjin University Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) School of Materials Science and EngineeringTianjin University Department of Civil and Environmental Engineering and Andlinger Center for Energy and the Environment Princeton University

Atmospheric water harvesting is an emerging strategy for decentralized and potable water supplies. However,water nucleation and microdroplet coalescence on condensing surfaces often result in surface flooding owing to the lack of a sufficient directional driving force for shedding. Herein, inspired by the fascinating properties of lizards and catfish, we present a condensing surface with engineered hydrogel patterns that enable rapid and sustainable water harvesting through the directional pumping and drag-reduced sliding of water droplets. The movement of microscale condensed droplets is synergistically driven by the surface energy gradient and difference in Laplace pressure induced by the arch hydrogel patterns. Meanwhile, the superhydrophilic hydrogel surface can strongly bond inner-layer water molecules to form a lubricant film that reduces drag and facilitates the sliding of droplets off the condensing surface. Thus, this strategy is promising for various water purification techniques based on liquid–vapor phase-change processes.

关键词： atmospheric water harvesting droplet manipulation bio-inspired condensation

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Journal of Geographical Sciences 2022年第4期32卷 589-604页

作者： FENG Huihui DING Ying ZOU Bin COHEN jason Blake YE Shuchao YANG Zhuolin QIN Kai LIU Lei gu Xiaodong School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring of Chinese Ministry of Education Changsha 410083China School of Atmospheric Sciences Sun Yat-sen UniversityGuangzhou 510275China School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116JiangsuChina College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China guangzhou Center for Rule of Green Development Law Studies Guangdong University of Foreign StudiesGuangzhou 510420China Southern Marine Science and Engineering guangdong Laboratory(guangzhou) Guangzhou 511458China

Vegetation plays an important role in the dry deposition of particles with significant spatial variability,but the magnitude remains unclear at the global *** the aid of satellite products,this study estimated the vegetation-related dry deposition of fine particulate matter(PM_(2.5)).Methodologically,dry deposition was first calculated using an empirical ***,deposition on the leaf surface was estimated to evaluate the influence of *** results showed that the mean deposition velocity(V_(d))of global PM_(2.5)was 0.91×10^(-3)μg·m^(-2)·s^(-1),with high velocities observed in sparsely vegetated regions because of the high friction *** the combined effect of the PM_(2.5)mass concentration and deposition velocity,the global mean dry deposition reached 0.47 g·m-^(2)·yr^(-1).Global vegetation absorbed 0.26 g·m-^(2)·yr^(-1)from PM_(2.5)pollution sources,contributing 54.98%of the total dry ***,vegetation-related dry deposition was high in the Amazon,Central Africa and East China due to dense vegetation coverage or serious ***,the increasing trends were mainly in Central Africa and India because of worsening air *** results of this study helped to clarify the impact of vegetation on air pollution,which supported related land management and planning for air quality improvement.

关键词： air pollution PM_(2.5) dry deposition vegetation change globe satellite

Multifunctional metaoptics based on bilayer metasurfaces

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Light(Science & Applications) 2019年第1期8卷 466-474页

作者： You Zhou Ivan I.Kravchenko Hao Wang Hanyu Zheng Gong gu jason Valentine Interdisciplinary Materials Science Program Vanderbilt UniversityNashvilleTN 37212USA Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Min H.Kao Department of Electrical Engineering and Computer Science University of TennesseeKnoxvilleTN 37996USA Department of Electric Engineering and Computer Science Vanderbilt UniversityNashvilleTN 37212USA Department of Mechanical Engineering Vanderbilt UniversityNashvilleTN 37212USA

Optical metasurfaces have become versatile platforms for manipulating the phase,amplitude,and polarization of light.A platform for achieving independent control over each of these properties,however,remains elusive due to the limited engineering space available when using a single-layer *** instance,multiwavelength metasurfaces suffer from performance limitations due to space filling constraints,while control over phase and amplitude can be achieved,but only for a single ***,we explore bilayer dielectric metasurfaces to expand the design space for *** ability to independently control the geometry and function of each layer enables the development of multifunctional metaoptics in which two or more optical properties are independently *** a proof of concept,we demonstrate multiwavelength holograms,multiwavelength waveplates,and polarization-insensitive 3D holograms based on phase and amplitude *** proposed architecture opens a new avenue for designing complex flat optics with a wide variety of functionalities.

关键词： surface. optics independently