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Improving Centralized Path Calculation Based on Graph Compression

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China Communications 2018年第6期15卷 120-124页

作者： Zhenglian Li Lixin Ji ruiyang Huang Shuxin Liu National Digital Switching System Engineering&Technological R&D Center ZhengzhouChina

Shortest-path calculation on weighted graphs are an essential operation in computer networks. The performance of such algorithms has become a critical challenge in emerging software-defined networks(SDN),since SDN controllers need to centralizedly perform a shortest-path query for every flow,usually on large-scale network. Unfortunately,one of the challenges is that current algorithms will become incalculable as the network size increases. Therefore, inspired by the compression graph in the field of compute visualization,we propose an efficient shortest path algorithm by compressing the original big network graph into a small one, but the important graph properties used to calculate path is reserved. We implement a centralized version of our approach in SDN-enabled network,and the evaluations validate the improvement compared with the well-known algorithms.

关键词： graph representation path compression shortest path

Distribution of Calcium Carbonate in the Process of Concrete Self-healing

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Journal of Wuhan University of Technology(Materials Science) 2016年第3期31卷 557-562页

作者：钱春香 LI ruiyang LUO Mian CHEN Huaicheng School of Materials Science and Engineering Southeast UniversityNanjing 211189China Research Institute of Green Construction Materials Southeast UniversityNanjing 211189China

The complete deposition distribution process of calcium carbonate is summarized in three directions of cracks. Distribution of calcium carbonate in the self-healing process of microbial concrete is studied in detail, with the help of a variety of analytical techniques. The results show that carbonate deposits along the x-axis direction of the cracks. The farther from the crack surfaces of concrete matrix in x-axis direction, the more the content of the substrate, the less content of calcium carbonate. Gradual accumulation of calcium carbonate along the y-axis direction is like building a house with bricks. Different repair points are gradually connected, and ultimately the whole of cracks are completely filled. In the z-axis direction, calcium deposits on the surface of fracture direction, when the crack is filled on the surface, because the internal crack hypoxia in the depths of cracks hardly produces calcium carbonate.

关键词： microbial concrete cracks self-healing calcium carbonate deposition

Effi ciency of Concrete Crack-healing based on Biological Carbonate Precipitation

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Journal of Wuhan University of Technology(Materials Science) 2015年第6期30卷 1255-1259页

作者：罗勉钱春香 LI ruiyang RONG Hui College of Materials Science and Engineering Southeast University Research Institute of Green Construction Materials Southeast University

The aim of this study was to improve the capacity for crack-repair in concrete by developing a new way. The self-healing agent based on biological carbonate precipitation was developed. Crack-healing capacity of the cement paste specimens with this biochemical agent was researched. Scanning electron microscopy（SEM） and X-ray diffraction（XRD） were used to characterize the precipitation in *** healing efficiency was evaluated by measuring the water permeability after crack healing as *** experimental results show that the applied biochemical agent can successfully improve the self-healing capacity of the cement paste specimens as larger cracks can be healed. The cracks with a width of 0.48 mm in the specimens with the biochemical agent are nearly fully healed by the precipitation after 80 d repair. SEM and XRD analysis results demonstrate that the white precipitation in cracks is calcium carbonate, which displays spherical crystal morphology. Meanwhile, the water permeability test result shows that the biochemical agent can significantly decrease the water permeability of the cement paste specimens, the water permeability of specimens with the biochemical agent respectively decreases by 84% and 96% after 7 d and 28 d immersion in water, however the control specimens only respectively decrease by 41% and 60%, which indicates that the bacteria-based concrete appears to be a promising approach to increase concrete durability.

关键词： crack-healing capacity concrete bacteria self-healing agent water permeability

Effect of Non-Convective Zone Thickness on Thermal Efficiency of Salt Gradient Solar Ponds

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Energy Engineering 2021年第4期118卷 1185-1195页

作者： Nan Li ruiyang Xu Caihong Zhang Guoping Wu School of Vehicles and Energy Yanshan UniversityQinhuangdao066004China Architecture Department Shijiazhuang Institute of Railway TechnologyShijiazhuang050541China

An improved radiation transmission and thermal efficiency model for solar ponds has been proposed based on both the Hull Model and Wang/Seyed-Yagoobi Model in this *** new model is more accurate to actual measured conditions because multiple reflections and turbidity effects are *** penetration,thermal conductivity loss and thermal efficiency under different Non-Convective Zone thicknesses are numerically analyzed and thoroughly *** results show thatΔT/I0 plays a critical role for the thermal efficiency of solar ***,it is found through calculation that there is an optimum thickness of the Non-Convective *** the Non-Convective Zone thickness is less than this critical threshold,both temperature and thermal efficiency are decreased with increasing ***,when the Non-Convective Zone thickness is greater than this critical threshold,the increasing turbidity within a certain range will be beneficial to improve the thermal efficiency of solar *** addition,optimum Non-Convective Zone thickness is also related to the temperature,turbidity,salinity variation and bottom reflectivity.

关键词： Solar pond Non-Convective Zone thickness thermal efficiency bottom reflective

Modeling the Covariance Matrix for the Power Spectra Before and After the BAO Reconstruction

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Research in Astronomy and Astrophysics 2024年第12期24卷 158-176页

作者： ruiyang Zhao Kazuya Koyama Yuting Wang Gong-Bo Zhao National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences Institute of Cosmology & Gravitation University of Portsmouth Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Chinese Academy of Sciences South America Center for Astronomy (CASSACA) National Astronomical Observatories of China

The baryon acoustic oscillations （BAO） reconstruction plays a crucial role in cosmological analysis for spectroscopic galaxy surveys because it can make the density field effectively more linear and more *** combination of the power spectra before and after the BAO reconstruction helps break degeneracies among parameters,then improves the constraints on cosmological *** is therefore important to estimate the covariance matrix between pre-and post-reconstructed power *** this work,we use perturbation theory to estimate the covariance matrix of the related power spectra multipoles,and check the accuracy of the derived covariance model using a large suite of dark matter halo catalogs at z=*** find that the diagonal part of the auto covariance is well described by the Gaussian prediction,while the cross covariance deviates from the Gaussian prediction quickly when k>0.1 h ***,we find the non-Gaussian effect in the nondiagonal part of the cross covariance is comparable to,or even stronger than,the pre-reconstruction *** adding the non-Gaussian contribution,we obtain good agreement between analytical and numerical covariance matrices in the non-diagonal part up to k;0.15 h *** agreement in the diagonal part is also improved,bu still under-predicts the correlation in the cross covariance block.

关键词： (cosmology:) cosmological parameters (cosmology:) large-scale structure of universe cosmology: theory

EMMD-Prony approach for dynamic validation of simulation models

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Journal of Systems Engineering and Electronics 2015年第1期26卷 172-181页

作者： Yongxing Chen Xiaoyan Wu Xiangwei Bu ruiyang Bai Air and Missile Defense College Air Force Engineering University

Model validation and updating is critical to model credibility growth. In order to assess model credibility quantitatively and locate model error precisely, a new dynamic validation method based on extremum field mean mode decomposition（EMMD） and the Prony method is proposed in this paper. Firstly, complex dynamic responses from models and real systems are processed into stationary components by EMMD. These components always have definite physical meanings which can be the evidence about rough model error location. Secondly, the Prony method is applied to identify the features of each EMMD component. Amplitude similarity, frequency similarity, damping similarity and phase similarity are defined to describe the similarity of dynamic *** quantitative validation metrics are obtained based on the improved entropy weight and energy proportion. Precise model error location is realized based on the physical meanings of these features. The application of this method in aircraft controller design provides evidence about its feasibility and usability.

关键词： dynamic validation extremum field mean mode decomposition(EMMD) Prony method error location model updating

WFRFT modulation recognition based on HOC and optimal order searching algorithm

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Journal of Systems Engineering and Electronics 2018年第3期29卷 462-470页

作者： LIANG Yuan DA Xinyu WU Jialiang XU ruiyang ZHANG Zhe LIU Hujun Information and Navigation College Air Force Engineering University

A hybrid carrier（HC） scheme based on weighted-type fractional Fourier transform（WFRFT） has been proposed *** most of the works focus on HC scheme＇s inherent characteristics, little attention is paid to the WFRFT modulation *** this paper, a new theory is provided to recognize the WFRFT modulation based on higher order cumulants（HOC）. First, it is deduced that the optimal WFRFT received order can be obtained through the minimization of 4 th-order cumulants, C_（42）. Then, a combinatorial searching algorithm is designed to minimize C_（42）.Finally, simulation results show that the designed scheme has a high recognition rate and the combinatorial searching algorithm is effective and reliable.

关键词： weighted-type fractional Fourier transform(WFRFT) modulation recognition higher order cumulants(HOC) combinatorial searching algorithm

Analysis of conductance and interfacial polarisation behaviours of silicone rubber based on frequency domain spectroscopy

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High Voltage 2024年第1期9卷 56-65页

作者： Hao Hu Zhidong Jia Xilin Wang ruiyang Guan Weinan Fan Simin Luo Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhenChina Guangzhou Power Supply China Southern Power Grid Company Ltd.GuangzhouChina

Silicone rubber(SR)is widely used for cable insulation and operates in multi-stress coupling *** dielectric properties and ageing performance are the essential factors affecting cable *** this study,the frequency domain spectroscopy of unaged SR and SR aged under various conditions is *** dielectric responses before and after ageing are analysed in depth by the conjoint analysis via multiple complex planes(permittivity,conductivity,and modulus).Typical conductivity and interfacial polarisation properties,as well as property changes resulting from thermal and tensile ageing,are *** results show that tensile ageing promotes conductance and interfacial polarisation,while thermal ageing shows the opposite *** on the multi-core model and charge carrier hopping transport model,thermal and tensile ageing mechanisms on the conductance and interfacial polarisation behaviours of SR are *** behaviours exhibit positively correlated changing characteristics,suggesting that the two behaviours may originate from a common *** carrier transport process,promoted by the tensile effect and slightly suppressed by the thermal effect,is the primary factor and considered an important indicator to evaluate the dielectric properties of SR insulation.

关键词： interfacial rubber insulation

Improving Transferable Targeted Adversarial Attack for Object Detection Using RCEN Framework and Logit Loss Optimization

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Computers, Materials & Continua 2024年第9期80卷 4387-4412页

作者： Zhiyi Ding Lei Sun Xiuqing Mao Leyu Dai ruiyang Ding School of Cryptography Engineering Information Engineering UniversityZhengzhou450000China

Object detection finds wide application in various sectors,including autonomous driving,industry,and *** studies have highlighted the vulnerability of object detection models built using deep neural networks when confronted with carefully crafted adversarial *** not only reveals their shortcomings in defending against malicious attacks but also raises widespread concerns about the security of existing *** existing adversarial attack strategies focus primarily on image classification problems,failing to fully exploit the unique characteristics of object detectionmodels,thus resulting in widespread deficiencies in their ***,previous research has predominantly concentrated on the transferability issues of non-targeted attacks,whereas enhancing the transferability of targeted adversarial examples presents even greater *** attack techniques typically employ cross-entropy as a loss measure,iteratively adjusting adversarial examples to match target ***,their inherent limitations restrict their broad applicability and transferability across different *** address the aforementioned challenges,this study proposes a novel targeted adversarial attack method aimed at enhancing the transferability of adversarial samples across object detection *** the framework of iterative attacks,we devise a new objective function designed to mitigate consistency issues arising from cumulative noise and to enhance the separation between target and non-target categories(logit margin).Secondly,a data augmentation framework incorporating random erasing and color transformations is introduced into targeted adversarial *** enhances the diversity of gradients,preventing overfitting to white-box ***,perturbations are applied only within the specified object’s bounding box to reduce the perturbation range,enhancing attack *** were conducted on the Microsoft

关键词： Object detection model security targeted attack gradient diversity