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Virtual Network Mapping Through Locality-aware Topological Potential and Influence Node Ranking

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Chinese Journal of Electronics 2014年第1期23卷 61-64页

作者： ZHANG Dong gao long College of Mathematics and Computer Science Fuzhou University

Efficiently mapping multiple independent Virtual networks(VNs) over a common infrastructure substrate is a challenging problem on cloud computing platforms and large-scale future Internet testbeds. Inspired by the idea of data fields, we apply a topological potential function to node ranking and propose an algorithm called Locality-aware node topological potential ranking(LNTPR), which can precisely and efficiently reflect the relative importance of nodes. Using LNTPR and the concept of locality awareness, we develop the Locality-aware influence choosing node(LICN) algorithm based on a node influence model that considers the mutual influence between a mapped node and its candidate mapping *** and LICN improve the integration of node and link mapping. Simulation results demonstrate that the proposed algorithms exhibit good performance in determining revenue, acceptance ratio, and revenue/cost ratio.

关键词： Network virtualization Virtual network Topological potential Influence model Locality-aware

A two-dimensional Richards equation solver based on CVODE for variably saturated soil water movement

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Science China(Technological Sciences) 2011年第12期54卷 3251-3264页

作者： TIAN FuQiang gao long HU HePing Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Development Research Center Ministry of Water Resources of China Beijing 100038 China

A numerical model of two-dimensional soil water movement under surface drip irrigation condition was developed. The physical process of soil water movement is described by 2D Richards equation,and the upper boundary condition is depicted by the improved moving ponded area boundary. The partial differential equation(PDE) is transformed into ordinary differential equations(ODEs) through spatial semi-discretization and numerically solved by an ordinary differential equation solver(CVODE) . The numerical and field experiments indicate the good performance of the model in terms of accuracy and efficiency. The model provides a useful tool for long-term simulation of soil water movement under surface drip irrigation. Also,the model can serve as a general 2D Richards equation solver for variably saturated soil water movement,which is named as TIVS model(Tsinghua Integrated Variably Saturated soil water movement model).

关键词： surface drip irrigation moving ponded area boundary CVODE Richards equation

Alternative flexible correction forming of a blade: multipoint correction with surface measurement and deformation simulation

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Advances in Manufacturing 2023年第4期11卷 587-600页

作者： Da-Wei Zhang Wen-long gao-Zhang Qi Zhang Xi’an Key Laboratory of Intelligent Equipment and Control School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China

Distortion during the forging or machining processes of a blade causes problems in subsequent manufacturing. This paper proposes an alternative multipoint correction method integrated with blade measurement, determination of correcting parameters, and adjustment of the correcting die. An iterative algorithm for determining the correcting parameters is proposed. Measuring equipment combining a laser displacement sensor with multipoint flexible support is manufactured to measure the blade shape. Multipoint correcting equipment with an adaptive lower die and rapid adjustment is manufactured, and software is developed for data analysis and equipment control. The correction experiment for a rough-machined steam-turbine blade indicates that the correcting parameters can be determined after one modification based on numerical simulation, and that a rough blade that meets the allowance for finish machining can be obtained using the determined correction parameters.

关键词： Blade Surface measurement Numerical simulation Multipoint correction

Parametric analysis of a packed bed thermal storage device with phase change material capsules in a solar heating system application

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Building Simulation 2021年第3期14卷 523-533页

作者： long gao Gegentana Junchao Bai Baizhong Sun Deyong Che Shaohua Li School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The goal of this study is to investigate the effect of key design parameters on the thermal performance of the packed bed heat storage device by numerical calculation.A one-dimensional,non-equilibrium packed bed latent heat storage mathematical model was established and the applicability of the model was *** results demonstrate that the inlet temperature of the heat transfer fluid(HTF)had the greatest influence on each *** the inlet temperature increased from 333 K to 363 K,exergy destruction increased threefold,effective heat storage time decreased by 67%,effective heat storage increased by 38%,and exergy efficiency decreased by 11%.The decrease of the capsule diameter had a positive effect on each evaluation *** to the sensitivity analysis,the order of importance of each parameter within their variation range was HTF inlet temperature,HTF flow rate,PCM capsule size and PCM initial temperature.

关键词： packed bed thermal energy storage solar heating system performance evaluation parametric analysis

The Limit Theorems for Random Walk with State Space R in a Space-time Random Environment

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Acta Mathematica Sinica,English Series 2008年第4期24卷 655-662页

作者： Wei Gang WANG Zhen long gao Di He HU School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 P. R. China School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China School of Mathematics Anyang Normal University Anyang 455000 P. R. China

We consider a discrete time random environment. We state that when the random walk on real number space in a environment is i.i.d., under the law, the law of large numbers, iterated law and CLT of the process are correct space-time random marginal annealed Using a martingale approach, we also state an a.s. invariance principle for random walks in general random environment whose hypothesis requires a subdiffusive bound on the variance of the quenched mean, under an ergodic invariant measure for the environment chain.

关键词： space-time random environment the law of large numbers CLT iterated law invariance principle

A Cauchy integral formula for(p,q)-monogenic functions withα-weight

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 545-553页

作者： gao long DU Xiao-jing LIU Yue XIE Yong-hong School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China

Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are ***,the Cauchy-Pompeiu formula is ***,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-monogenic function... 详细信息

关键词： (p q)-monogenic functions with-weight Cauchy-Pompeiu formula Cauchy integral formula Cauchy integral theorem

Urban traffic congestion propagation and bottleneck identification

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Science in China(Series F) 2008年第7期51卷 948-964页

作者： long JianCheng gao ZiYou REN HuaLing LIAN AiPing State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China

Bottlenecks in urban traffic network are sticking points in restricting network collectivity traffic efficiency. To identify network bottlenecks effectively is a foundational work for improving network traffic condition and preventing traffic congestion. In this paper, a congestion propagation model of urban network traffic is proposed based on the cell transmission model （CTM）. The proposed model includes a link model, which describes flow propagation on links, and a node model, which represents link-to-link flow propagation. A new method of estimating average journey velocity （AJV） of both link and network is developed to identify network congestion bottlenecks. A numerical example is studied in Sioux Falls urban traffic network. The proposed model is employed in simulating network traffic propagation and congestion bottleneck identification under different traffic demands. The simulation results show that continual increase of traffic demand is an immediate factor in network congestion bottleneck emergence and increase as well as reducing network collectivity capability. Whether a particular link will become a bottleneck is mainly determined by its position in network, its traffic flow （attributed to different OD pairs） component, and network traffic demand.

关键词： cell transmission model node model congestion bottleneck average journey velocity

Nacre-inspired Green Artificial Bionanocomposite Films from the Layer-by-Layer Assembly of Montmorillonite and Chitosan

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Chinese Journal of Polymer Science 2014年第6期32卷 675-675,676-680页

作者： Sha-sheng Wang Ying-qi Shu Ben-liang Liang long-cheng gao Min gao 殷鹏刚郭林 School of Chemistry & Environment Beihang University College of Materials Science and Engineering Department of Chemistry Beijing University of Technology

The simple LBL technique was introduced to fabricate green nacre-like chatosan/montmorillonite （CHI/MMT） films. The results of SEM and XRD analysis demonstrate that the produced CHI/MMT composites films stacked densely together to bring out well-defined nacre-like brick-mortar structure. The nanoindentation technique is used to characterize the mechanical properties of the layered nanocomposite films, which show enhanced mechanical modulus （up to -6.64 GPa） compared with the pure chitosan.

关键词： Nacre-inspired Layer-by-layer films Chitosan Montmorillonite Nanoindentation.

Smoothness Prior Approach for Spectral Smoothing and Baseline Correction

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Journal of Beijing Institute of Technology 2017年第1期26卷 121-128页

作者： Lu Li He Chen Siying Chen Yinchao Zhang long gao School of Optoelectronics Beijing Institute of Technology Beijing 100081 China Beijing Institute of Space Mechanics & Electricity Beijing 100094 China

Smoothness prior approach for spectral smoothing is investigated using Fourier frequency filter *** show that the regularization parameter in penalized least squares could continuously control the bandwidth of low-pass ***,due to its property of interpolating the missing values automatically and smoothly,a spectral baseline correction algorithm based on the approach is *** algorithm generally comprises spectral peak detection and baseline ***,the spectral peak regions are detected and identified according to the second ***,generalized smoothness prior approach combining identification information could estimate the baseline in peak *** with both the simulated and real spectra show accurate baseline-corrected signals with this method.

关键词： smoothness priors low-pass filter second derivative spectral smoothing baselinecorrection