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Rail Expansion Devices Monitored by FBG Sensors on an Urban Railway Viaduct

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Photonic Sensors 2014年第2期4卷 173-179页

作者： Weilai LI jin pang Xiaoshan LU Jie LIU National Engineering Lab of Fiber Optic Sensing Technology Wuhan University of Technology 122 Luoshi RoadWuhan 430070 China Key Lab of Fiber Optic Sensing Technology and Information Processing Wuhan University of Technology 122 LuoshiRoad Wuhan 430070 China

The fiber Bragg grating （FBG） sensing technology was used to monitor the situation of a crevice of the continuous beam joint and rails near rail expansion devices on a viaduct of the urban railway. The monitoring items consisted of the rail temperature, rail displacement, viaduct beam displacement, and strain of sliding rail in the rail expansion device section. The strain sensor was a prefabricate FBG strain gauge, the displacement sensor with different scales used an FBG stress ring, and the FBG of the temperature sensor was pre-drawn and fixed in a metal tube. Compensation sensors were used to balance environmental temperature changes. All FBGs were suspended adhered, therefore the chirped phenomenon of the FBG reflection peak was avoided, and the measurement accuracy was improved. The monitoring results matched to the manual test and theoretical estimation.

关键词： Fiber Bragg grating urban rail viaduct rail expansion device monitor

FBG Stress-Sensibilized Monitor for Railway Switch Pole On-Line Monitoring

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Photonic Sensors 2014年第3期4卷 269-273页

作者： Weilai LI Jie LIU Jianjun PAN jin pang Xiaoshan LU National Engineering Lab of Fiber Optic Sensing Technology Wuhan University of Technology Wuhan 430070 China Key Lab of Fiber Optic Sensing Technology and Information Processing Ministry of Education Wuhan University ofTechnology Wuhan 430070 China

The fiber Bragg grating （FBG） sensing technology is used to dynamically monitor multiple parameters of railway switch machine poles, including time of movement, direction and quantity of loading and locking force, and states of loading resistance. This paper presents the design and implementation of a railway switch pole strain on-line monitoring system based on the FBG stress-sensibilized monitor for a Siemens S700K switch machine. The ring shape FBG strain gauge and stress-sensibilized methods significantly increased the monitoring sensitivity. Installing approaches adapted the harsh environment in the railway application. The monitoring results showed the high sensitivity and high reliability of this monitoring system. This application provides a long-term and on-line detecting method which could meet railway switch condition monitoring demands of more than 100,000 switch machines in the country.

关键词： Fiber Bragg grating railway switch pole strain dynamically monitor

Encrypted traffic classification based on fusion of vision transformer and temporal features

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The Journal of China Universities of Posts and Telecommunications 2023年第2期30卷 73-82页

作者： Wang Lanting Hu Wei Liu Jianyi pang jin Gao Yating Xue jingyao Zhang Jie School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China State Grid Information and Telecommunication Branch Beijing 100761China Information and Telecommunication Company State Grid Shandong Electric Power CorporationJinan 250001China

Aiming at the problem that the current encrypted traffic classification methods only use the single network framework such as convolutional neural network(CNN),recurrent neural network(RNN),and stacked autoencoder(SAE),and only construct a shallow network to extract features,which leads to the low accuracy of encrypted traffic classification,an encrypted traffic classification framework based on the fusion of vision transformer and temporal features was *** transformer network(BoTNet)was used to extract spatial features and bi-directional long short-term memory(BiLSTM)was used to extract temporal *** the two sub-networks are parallelized,the feature fusion method of early fusion was used in the framework to perform feature ***,the encrypted traffic was identified through the fused *** experimental results show that the BiLSTM and BoTNet fusion transformer(BTFT)model can enhance the performance of encrypted traffic classification by fusing multi-dimensional *** accuracy rate of a virtual private network(VPN)and non-VPN binary classification is 99.9%,and the accuracy rate of fine-grained encrypted traffic twelve-classification can also reach 97%.

关键词： encrypted traffic classification vision transformer temporal feature

A Reasonable Approach for the Development of Shale Gas Wells with Consideration of the Stress Sensitivity

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Fluid Dynamics & Materials Processing 2019年第1期15卷 39-51页

作者： jin pang Di Luo Haohong Gao Jie Liang Yuanyuan Huang Qi Liu Chongqing University of Science and Technology ChongqingChina Shunan Gas Production Plant PetroChina Southwest Oil&Gasfield CompanyLuzhouChina Southwest Gas Production Plant PetroChina Zhejiang Oilfield BranchYibinChina Linpan Drilling Branch Sinopec Southwest Petroleum Engineering Co.Ltd.LinpanChina

High-pressure deep shale gas reservoirs are usually highly *** the reasonable production mode of shale gas well is built,the impact of strong stress sensitivity should be fully ***,this study calculated the relationship between permeability and formation pressure under different elastic modulus based on the shale lithology of Long Ma Xi formation in Sichuan Basin by testing and analysing the mechanical parameters of the *** to numerical simulation result,when the elastic modulus exceeds 14.0 GPa,the stress sensitivity of the matrix will slight affect the cumulative gas production of shale ***,the changing relation between fracture conductivity and permeability with fracture pressure and the time of pressure acts were experimentally *** numerical simulation result suggested that the 30-year cumulative gas production considering the stress sensitivity was reduced by 13.5%compared with the 30-year cumulative gas production without considering the stress ***,the production of different production modes under different stress sensitive characteristics was predicted using numerical simulation *** the matrix and fractures are fixed with a same stress-sensitive curve,the initial production allocation will not significantly impact the cumulative gas *** the fractured fractures are subjected to a varying stress sensitive curve,the lower production allocation will result in higher post-production and cumulative gas production.

关键词： Shale stress sensitivity production mode production allocation fractures matrix

The effects of doubly excited states on ionization balance

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原子与分子物理学报 2006年第B4期23卷 37-40页

作者： pang jin-qiao WU Ze-qing YAN Jun Institute of Applied Physics and Computstional Mathematics Laboratory of Computational Physics P. O. Box 8009-57 Beijing 100088 ChinaP.R. China

The effects of highly doubly excited states on ionization balance are investigated. In the calculation, A Collisional-Radiative model in Detailed-Configuration-Accounting (DCA) is applied to population calculations for NLTE plasmas. Configuration-averaged rate coefficients that needed in the rate equations are obtained based on the first order perturbation theory. The Hatree-Fock-Slater self-consistent-field method is used to calculate the electron wave functions. The mean ionization stage of high-Z plasma Lu is presented. The comparison shows that the mean ionization stage increases more than 3 stages when doubly excited states 5l6l' and 5l5l' are not included in the population calculations.

关键词：非局部热力学平衡电离平衡 NLTE 碰撞辐射模型

An Introduction to Convex Optimization Theory in Communication Signals Recognition

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Journal of Harbin Institute of Technology(New Series) 2013年第5期20卷 14-19页

作者： jin-Feng pang Yun Lin Xiao-Chun Xu Zheng Dou Zi-Cheng Wang College of Information and Communication Engineering Harbin Engineering University

In this paper,convex optimization theory is introduced into the recognition of communication signals. The detailed content contains three parts. The first part gives a survey of basic concepts,main technology and recognition model of convex optimization theory. Special emphasis is placed on how to set up the new recognition model of communication signals with multisensor reports. The second part gives the solution method of the recognition model,which is called Logarithmic Penalty Barrier Function. The last part gives several numeric simulations,in contrast to D-S evidence inference method,this new method can also generate reasonable recognition results. Moreover,this new method can deal with the form of sensor reports which is more general than that allowed by the D-S evidence inference method,and it has much lower computation complexity than that of D-S evidence inference method. In addition,this new method has better recognition result,stronger anti-interference and robustness. Therefore,the convex optimization methods can be widely used in the recognition of communication signals.

关键词： convex optimization theory signal recognition D-S evidence theory logarithmic penalty barrier function

Construction of the Seed-Coat cDNA Microarray and Screening of Differentially Expressed Genes in Barley

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 695-700页

作者： jin-Song pang*, Meng-Yuan HE, and Bao LIU Laboratory of Molecular Epigenetics, Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024, China Laboratory of Molecular Epigenetics Institute of Genetics and Cytology Northeast Normal University

Some barley mutants can synthesize neither anthocyanins nor proanthocyanidins in the seed coat, which is related to several genes in locus Ant13, but the exact model of action remains unknown. We used the cDNA microarray technology with barley transcription-deficient mutant (ant13-152) that does not synthesize proanthocyanidins as the tester, and its wild type genotype (Triumph) as the driver, to study this question. Six-thousand and forty-eight clones from the wild type Morex testa+pericarp cDNA library were amplified using PCR, and the DNA fragments were spotted on commercial amino-modified glass slide as microarray. The mRNAs from the developing seed coat (8–15 days) of both the mutant and the wild-type barley plants were isolated, and labeled respectively with Cy3-dUTP and Cy5-dUTP when reversely trans- cribed to cDNAs. The labeled cDNAs were used as probes, mixed at the same molar concentration, and hybridized with the DNA fragments on the slide. Seventy clones exhibiting marked differential expression (ratio>4) were identified from the microarray. All the 25 cDNA clones that showed an over-expression in wild type in comparison to the mutant ant13-152 were sequenced. It was found that most of these over- expressing clones were transcription/translation and hordein-associated genes. These results have laid a solid material basis for further elucidation of the metabolic pathway in proanthocyanidin synthesis in barley and likely other plants.

关键词： barley seed coat proanthocyanidin cDNA microarray

Putrescine, spermidine, and spermine play distinct roles in rice salt tolerance

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Journal of Integrative Agriculture 2020年第3期19卷 643-655页

作者： Md Azizul ISlam pang jin-huan MENG Fan-wei LI Ya-wen XU Ning YANG Chao LIU Jun State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of Sciences(CAS)Beijing 100101P.R.China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049P.R.China Department of Biotechnology and Genetic Engineering Faculty of Applied Science and TechnologyIslamic UniversityKushtia 7003Bangladesh

Polyamines(PAs) play diverse roles in plant growth and development,as well as responses to environmental *** this study,the effects of PAs on rice salt tolerance were *** stress resulted in the alteration of endogenous PAs levels in rice roots and leaves,where spermidine(Spd) and spermine(Spm) contents were increased,and putrescine(Put) content was ***-qPCR analysis revealed that PAs biosynthesis-related genes ADC1,ODC,and Arginase were significantly downregulated by salt treatment;however,SAMDC transcription was significantly *** Spm enhanced rice salt tolerance remarkably;however,exogenous Put and Spd undermined rice salt *** rice plants overexpressing SAMDC display a higher ratio of Spm/(Put+Spd) and enhanced salt *** stress also increased polyamine oxidase activities in rice,resulting in elevated reactive oxygen species(ROS) *** findings revealed that accumulation of Put and Spd substantially reduced salt tolerance in rice,likely by facilitating ROS production;whereas,conversion of Put and Spd to Spm contributes to rice salt tolerance.

关键词： rice polyamines NaCl polyamine oxidase guazatine

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变质处理对低铜高锌黄铜冲击韧性的影响

铸造 2006年第9期55卷 953-955页

作者：庞晋山新会出入境检验检疫局广东江门529100

近年来,随着人们对低铜高锌黄铜的研究不断深入,其应用范围也在不断拓宽。但随着锌含量的增加,合金的组织结构发生了根本的变化,尤其是星花状γ相的出现,严重影响了合金的力学性能。本试验通过变质处理的方法设法改变γ相的形态及其分布... 详细信息

近年来,随着人们对低铜高锌黄铜的研究不断深入,其应用范围也在不断拓宽。但随着锌含量的增加,合金的组织结构发生了根本的变化,尤其是星花状γ相的出现,严重影响了合金的力学性能。本试验通过变质处理的方法设法改变γ相的形态及其分布,多次试验证明变质处理对改善低铜高锌合金的力学性能特别是冲击韧性有较好的效果。

关键词：变质处理冲击韧性 γ相