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Load Balancing-Based Routing Optimization Mechanism for Power Communication Networks

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China Communications 2016年第8期13卷 169-176页

作者： Ningzhe Xing Siya Xu Sidong Zhang Shaoyong guo School of Electronic and Information Engineering Beijing Jiaotong University Beijing 100044 China State Grid Jibei Electric Power Company Limited Information & Telecommunication Branch Beijing 1000053 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In power communication networks, it is a challenge to decrease the risk of different services efficiently to improve operation reliability. One of the important factor in reflecting communication risk is service route distribution. However, existing routing algorithms do not take into account the degree of importance of services, thereby leading to load unbalancing and increasing the risks of services and networks. A routing optimization mechanism based on load balancing for power communication networks is proposed to address the abovementioned problems. First, the mechanism constructs an evaluation model to evaluate the service and network risk degree using combination of devices, service load, and service characteristics. Second, service weights are determined with modified relative entropy TOPSIS method, and a balanced service routing determination algorithm is proposed. Results of simulations on practical network topology show that the mechanism can optimize the network risk degree and load balancing degree efficiently.

关键词： power communication networks load balancing routing optimization

Comparison between the 3D numerical simulation and experiment of the bubble near different boundaries

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Science China(Physics,Mechanics & Astronomy) 2008年第12期51卷 1914-1925页

作者： ZHANG AMan YAO XiongLiang LI Jia guo Jun College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

Based on the potential flow theory, the vortex ring is introduced to simulate the toroidal bubble, and the boundary element method is applied to simulate the evo- lution of the bubble. Elastic-plasticity of structure being taken into account, the interaction between the bubble and the elastic-plastic structure is computed by combining the boundary element method (BEM) and the finite element method (FEM), and a corresponding 3D computing program is developed. This program is used to simulate the three-dimensional bubble dynamics in free field, near wall and near the elastic-plastic structure, and the numerical results are compared with the existing experimental results. The error is within 10%. The effects of different boundaries upon the bubble dynamics are presented by studying the bubble dy- namics near different boundaries.

关键词： bubble three-dimensional potential flow theory elastic-plasticity boundary

Analysis of nonlinear multi-field coupling responses of piezoelectric semiconductor rods via machine learning

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International Journal of Smart and Nano Materials 2024年第1期15卷 62-74页

作者： Chuwei Wu Zhengguang Xiao Yuting guo Chunli Zhang Department of Engineering Mechanics Zhejiang UniversityHangzhouZhejangChina Huanjiang Laboratory ZhujiChina

Piezoelectric semiconductors(PSs)have widespread applications in semiconductor devices due to the coexistence of piezoelec-tricity and semiconducting *** is very important to conduct a theoretical analysis of PS ***,the present of nonlinearity in the partial differential equations(PDEs)that describe those multi-feld coupling mechanical behaviors of PSs poses a significant mathematical challenge when studying these PS *** this paper,we present a novel approach based on machine learning for solving multi-field coupling problems in PS structures.A physics-informed neural networks(PINNs)is constructed for predicting the multi-field coupling behaviors of PS rods with extensional *** utilizing the proposed PINNs,we evaluate the multi-field coupling responses of a ZnO rod under static and dynamic axial *** results demonstrate that the proposed PINNs exhibit high accuracy in solving both static and dynamic problems associated with Ps *** provides an effective approach to predicting the nonlinear multi-feld coupling phe-nomena in PS structures.

关键词： PS rod multi-feld coupling response machine learning PINNs

Evolution Characteristics of Government-Industry-University-Research Cooperative Innovation Network for China＇s Agriculture and Influ- encing Factors： Illustrated According to Agricultural Patent Case

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Chinese Geographical Science 2018年第1期28卷 137-152页

作者： LI Erling YAO Fei XI Jiaxin guo Chunyang Key Research Institute of Yellow River Civilization and Sustainable Development/Henan Collaborative Innovation Center for the Yellow River Civilization Heritage and Modern Civilization Construction/College of Environment and Planning Henan University Kaifeng 475001 China Collaborative Innovation Center of Urban-Rural Coordinated Development Henan Province Kaifeng 475004 China Gemmological Institute China University of Geosciences (Wuhan) Wuhan 430074 China

Under the special background of China, the cooperative innovation between different government-industry-university-research institutes plays an increasingly important role in the agricultural field. However, the existing literature has paid little attention to it. Considering the cooperation patents, published in the agriculture field stemming from the Full-text Database of China Patents as the study object, the spatial and institutional attribute of the authors as the data source, and by combining the social network and spatial econometrics analysis, this paper analyzes the structure evolution characteristics of cooperative innovation networks of agricultural government-industry-university-research institute in the city level of China in 1985–2014, based on the triple helix theory, with the influence factors discussed. This shows that, 1) since 1985, China's agricultural innovation level has been substantially increased, but the development degree of the cooperative innovation network is low, and the patent cooperation mainly relies on authors in the same unit; 2) enterprises play a leading role in the agricultural cooperative innovation. The effect of the government and hybrid organizations driven by the government is not obvious; 3) the cooperative innovation in the province and city dominates, and a multi-pole pattern has been formed. The cooperative innovation network structure evolves from a single helix empty core and double helix multi core to a double helix hierarchical network; 4) the city's science, education funding and personnel investment are key factors determining the agricultural cooperative innovation, while the agricultural development of the city presents slight negative impacts on it. The spatial mismatch of supply and demand is present in the technical cooperative innovation of China's agriculture. Therefore, the science enhancement and education investment to big agricultural provinces should be promptly implemented.

关键词： cooperation innovation networks government-industry-university-research institute China's agricultural patent SocialNetwork Analysis (SNA)

Separation/Extraction/Detection of Chloramphenicol Using Binary Small Molecule Alcohol-Salt Aqueous Two-phase System Coupled with High-performance Liquid Chromatography

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Chemical Research in Chinese Universities 2019年第2期35卷 209-215页

作者： guo Donggang NI Liang WANG Liang SHAO Li School of the Environment and Safety Engineering School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013R R. China Key Laboratory of Preparation and Application of Environmental Friendly Materials Jilin Normal UniversityMinistry of EducationChangchun 130103P. RChina

A green and sensitive sample separation and purification method coupled with high-perfomiance liquid chromatography(HPLC)was developed for the analysis of chioramphenicol(CAP).One element small molecule alcohol-salt aqueous two-phase system(ATPS)can't effectively adjust the polarity of the system,but binary small molecule alcohol-salt ATPS can adjust the polarity and improve the extraction efficiency of antibiotics.A binary aqueous two-phase system based on 1-propanol+2-propanol and NaH2PO4 system was formed and applied to the separation and purification of trace CAP in real *** influence factors on partition behaviors of CAP were discussed,including the types and mass of salts,the volume ratio of alcohol,the pH,temperature and the standing *** optimal condition was found at pH=5.0,2.5 g of NaH2PO4,3.0 mL of 1-propanol and 2-propanol(volume ratio 1:1)and 30℃by using response surface *** this optimal condition,the extraction efficiency of CAP reached 98.91%,and partition coefficient of CAP was 17.31.

关键词： Binary small molecule alcohol aqueous two-phase system Partition behavior Chloramphenicol Extraction efficiency

Waveform Design for Integrated Sensing and Communication Systems Based on Interference Exploitation

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Journal of Communications and Information Networks 2022年第4期7卷 447-456页

作者： Tian Liu Yinghong guo Lingfeng Lu Bin Xia Southwest China Institute of Electronic Technology Chengdu 610036China Institute of Wireless Communications Technology(IWCT)and Shanghai Key Laboratory of Digital Media Processing and Transmission Shanghai Jiao Tong UniversityShanghai 200240China

Integrated sensing and communication(ISAC)is a spectrum and energy efficient approach to realizing dual functions by a unified hardware *** this paper,we consider a multiple-input multiple-output(MIMO)ISAC system,where the transmitted waveform consisting of communication signals and dedicated sensing signal is optimized for dual purposes of estimating targets and serving downlink single-antenna ***,the sensing interference and multi-user interference are exploited,rather than suppressed,by the waveform design *** joint waveform design problem is formulated by maximizing the constructive interference(CI)while ensuring the power budget and waveform similarity error with the benchmark signal,which limits the sensing estimation *** obtain the benchmark signal which achieves the optimal estimation performance,we propose a semidefinite relaxation based algorithm to solve the optimization *** clarity,we derive the real representation of the complex joint waveform design problem and prove its *** results verify the superiority of the proposed CI-based waveform design when the interference was efficiently exploited as a useful signal source achieving favorable symbol error ratio ***,the dedicated sensing signal provides more degree of freedom for waveform design.

关键词： ISAC CI waveform design Cramer-Rao bound

Group Invariant Solutions of the Two-Dimensional Elastodynamics Problem in the Polar Coordinate System

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Chinese Physics Letters 2012年第8期29卷 149-151页

作者： LI Hou-guo HUANG Ke-Fu Department of Mechanics and Aerospace Engineering College of EngineeringPeking UniversityBeijing 100871

Some group invariant solutions of the two-dimensional elastodynamics problem in linear homogeneous isotropic materials are considered using the group-theoretical *** the polar coordinate system,three group invariant solutions are constructed by the invariants of the Lie group,which are admitted by the governing equations for the two-dimensional elastodynamics *** graphical figures of the group invariant solutions are presented,and the physical meanings of the group invariant solutions are expounded in some cases.

关键词： method problem invariant

Fuel optimal low thrust rendezvous with outer planets via gravity assist

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Science China(Physics,Mechanics & Astronomy) 2011年第4期54卷 756-769页

作者： guo TieDing JIANG FangHua BAOYIN HeXi LI JunFeng School of Aerospace Tsinghua University Beijing 100084 China

Low thrust propulsion and gravity assist (GA) are among the most promising techniques for deep space *** this paper the two techniques are combined and treated comprehensively,both on modeling and numerical *** optimal orbit rendezvous via multiple GA is first formulated as optimal guidance with multiple interior constraints and then the optimal necessary conditions,various transversality conditions and stationary conditions are derived by Pontryagin's Maximum Principle (PMP).Finally the initial orbit rendezvous problem is transformed into a multiple point boundary value problem (MPBVP).Homotopic technique combined with random searching globally and Particle Swarm Optimization (PSO),is adopted to handle the numerical difficulty in solving the above MPBVP by single shooting *** scenarios in the end show the merits of the present approach.

关键词： low thrust fuel optimal trajectory maximum principle homotopic technique gravity assist

Hybrid Particle Swarm Optimization with Differential Evolution for Numerical and Engineering Optimization

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International Journal of Automation and computing 2018年第1期15卷 103-114页

作者： guo-Han Lin Jing Zhang Zhao-Hua Liu College of Electrical and Information Engineering Hunan University College of Electrical and Information Hunan Institute of Engineering School of Information and Electrical Engineering Hunan University of Science and Technology

In this paper, a hybrid particle swarm optimization （PSO） algorithm with differential evolution （DE） is proposed for numerical benchmark problems and optimization of active disturbance rejection controller （ADRC） parameters. A chaotic map with greater Lyapunov exponent is introduced into PSO for balancing the exploration and exploitation abilities of the proposed algorithm. A DE operator is used to help PSO jump out of stagnation. Twelve benchmark function tests from CEC2005 and eight real world opti- mization problems from CEC2011 are used to evaluate the performance of the proposed algorithm. The results show that statistically, the proposed hybrid algorithm has performed consistently well compared to other hybrid variants. Moreover, the simulation results on ADRC parameter optimization show that the optimized ADRC has better robustness and adaptability for nonlinear discrete-time systems with time delays.

关键词： Particle swarm optimization (PSO) active disturbance rejection control (ADRC) differential evolution algorithm chaoticmap parameter tuning.