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Dynamic Damage Detection and Assessment on the Bogie Frame of High-Speed Train Based on the Coupled Elastic and Multibody Dynamics Scheme

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Acta Mechanica Solida Sinica 2023年第5期36卷 633-646页

作者： Yating Han wangdong Shi Wenjie Feng School of Civil Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Key Laboratory for Mechanics of Smart Materials and Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The dynamic cumulative damage of rigid-flexible coupling model of high-speed train with flexible bogie frame is performed by using the coupled scheme of elastic and multibody dynamics *** motion equations of the present problem are firstly established by integrating the finite element method and floating frame of reference approach based on the virtual power principle and D'Alembert *** process of condensing the elastic DOFs of the obtained finite element model involving the incorporation of the substructure technique and sparse approximate inverse method is tentatively carried ***,the motion equations are further solved by virtue of the generalized α method and the Jacobian-free Newton-Krylov *** the superiority of coupled scheme is proven by comparing with the traditional ***,besides the dynamic behaviors of the considered vehicle model,the time-variations of stresses on the elastic bogie frame's dangerous nodes and the distributions of stresses of bogie frame at some specified moments are synchronously calculated and *** importantly,the real-time and time-varying cumulative damages of some typical nodes on bogie frame are investigated.

关键词： Coupled elastic and multibody dynamics scheme Flexible bogie frame Dynamic damage analysis

Laser Cladding of an Al-11.7Wt%Si Alloy on ZM5 Magnesium Alloy to Enhance the Corrosion Resistance

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材料热处理学报 2004年第05B期25卷 992-995页

作者： CHENChang-jun WANGMao-cai wangdong-sheng StateKeyLabatoryforCorrosionandProtection InstituteofMetalResearchChineseAcademyofSciencesShenyangP.R.China110016

Magnesium alloy is an important engineering materials, but the wider application is restricted by poor corrosion resistance. An attempt was made to enhance the corrosion resistance and microhardness of a Mg-Al base ZM5 alloy by laser cladding of Al-11.7Wt%Si alloy powder with thickness *** and 1.7mm. The microstructure, phase and corrosion properties were analyzed by scanning electron micrographic (SEM), electron probe microanalysis(EPMA), vicker hardness tester and corrosion measurement system, respectively. Microhardness of the cladding layer was enhanced to 150-375Hv as compared to 60-99Hv of the substrate. The corrosion potential (Ecorr) of the cladding sample was 80mv higher than the substrate, while the corrosion current (Icorr) was lower than the substrate.

关键词：镁合金激光包覆显微结构 ZM5 耐蚀性

Interaction of PACls with sulfate

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Journal of Environmental Sciences 2004年第3期16卷 420-422页

作者： XUYi wangdong-sheng TANGHong-xiao SKLEAC ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China

This article discusses the influential factors on Al 13 separation considering the interaction of sulfate with various polyaluminum chloride(PACl). The experimental results showed that the basicity( B =[OH]/[Al]), the concentration of PACl and Al/SO 4 ratio exhibited significant roles in the PACl sulfate reaction. It indicated that different species in various PACl underwent different reaction pathway with sulfate. The Al c, colloidal species, formed precipitation quickly with sulfate, while Al b, oligomers and polymers, underwent slow crystallization. And Al a, monomers, reacted with sulfate to form soluble complexes. The kinetic difference of reaction made it possible to realize the separation of Al b and further purification. The decrease of Al a resulted in the limit of ferron method was also mentioned.

关键词： PACl sulfate Al13 kinetic separation

Phosphorus fractionation and bio-availability in Taihu Lake(China) sediments

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Journal of Environmental Sciences 2005年第3期17卷 384-388页

作者： ZHOUAi-min wangdong-sheng TANGHong-xiao SKLEAC ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China

Typical sediments from Taihu Lake, a meso-to-hypereutrophic lake, were collected and examined on the basis of P-fractionation by sequential extraction scheme. Sedimentary inorganic phosphorus were fractioned into four forms and the rank order according to the mean concentration of P-fractions in Taihu Lake was NaOH-P>BD-P>HCl-P>NH_4Cl-P. The concentrations of BD-P were linearly correlated with the content of active Fe(R2=0.96). Also, the linear relationship between the sum of BD-P and NaOH-P and the sum of active Fe and active Al content was observed within the six sediments investigated(R2=0.96). Moreover, the bio-available phosphorus(BAP) content was estimated by the sum of NH_4Cl-P, BD-P, and NaOH-P, viz. BAP=NH_4Cl-P+NaOH-P+BD-P. In Taihu Lake, the BAP contents are ranging from 0.10 mg/g dw to 1.25 mg/g dw, and average 0.40 mg/g dw for all sediment samples. The relative contributions of BAP to total sedimentary phosphorus(TP) and inorganic sedimentary phosphorus(IP) range from 18.67% to 50.79%(33.61% on average) and from 52.82% to 82.09%(67.81% on average), respectively.

关键词： phosphorus fractionation bio-availability sediment Taihu Lake

Energy Efficient MAC Protocol for Wireless Full-Duplex Networks

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China Communications 2018年第1期15卷 35-44页

作者： Yu Song wangdong Qi Wenchi Cheng Army Engineering University Nanjing 210007 China National University of Defense Technology Xi'an 710106 China State key Laboratory Services Networks Xidian University Xi'an 710048 China

The wireless full-duplex(FD) nodes can transmit and receive at the same time using the same frequency-band. Currently, the latest FD media access control(MAC) protocols mainly focus on how to convert the physical layer gains of FD nodes to the throughput gain of wireless FD networks, but pay little attention to the energy consumptions of FD nodes. In this paper, we propose an energy efficient FD MAC protocol. According to the values of self-interference cancellation coefficients corresponding to the nodes of each FD pair and the signal propagation attenuation, the proposed protocol can adaptively select the communication mode of the FD pair between the full-duplex and half-duplex. Also, the minimum transmit power for FD nodes can be obtained to achieve high energy efficiency. We develop an analytical model to characterize the performance of our protocol. The numerical results show that the proposed MAC protocol can optimize the system throughput and reduce the transmission energy consumptions of nodes simultaneously as compared with those of the existing works.

关键词： wireless full-duplex networks MAC protocol energy efficient self-interference cancellation coefficient

Cyclopenta-fused perylene: a new soluble, stable and functionalizable rylene building block

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Science Bulletin 2015年第14期60卷 1266-1271页

作者： wangdong Zeng Qingbiao Qi Jishan Wu Department of Chemistry National University of Singapore Institute of Materials Research and Engineering

We report a facile synthesis of a [l,12-b,c,d]- cyclopenta-fused perylene 5 from the parent perylene via a formylation-oxidative esterification-nucleophilic additionfollowed-by-Friedel-Crafts alkylation strategy. Compared with the perylene, dye 5 exhibits much higher solubility, smaller energy gap, and can undergo regio-selective bromination at the peri-positions. Compared with the N- annulated perylene 8, compound 5 shows lower HOMO energy level and is more stable in air. Therefore, 5 can be regarded a new versatile building block for the development of high-order soluble and stable rylenes and various perylene-based functional materials.

关键词： Organic dye Rylene Perylene Polycyclic aromatic hydrocarbon

Genomic cloning and sequencing of betaine aldehyde dehydrogenase gene in spinach

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Chinese Science Bulletin 1998年第4期43卷 325-330页

作者： Shu Weiguo Ai wangdong Chen Shouyi Chinese Acad Sci Inst Genet Beijing 100101 Peoples R China

A genomic library derived from leaves of spinach was constructed with the λGem11_BamHI Arms as the vector. The library was screened using the BADH cDNA of mountain spinach as a probe and six positive clones were obtained through three rounds of screening. One of the positive clones named D, which was hybridized with the 5′600 bp fragment of mountain spinach BADH cDNA, was selected and further analyzed. The size of the insert in clone D was about 12 kb. 8 856 nucleotides of the insert were sequenced which contained 2 459 nucleotides of 5′ noncoding region, 6 111 nucleotides of the complete sequence of the BADH gene, and 286 nucleotides of a 3′ noncoding region. The result of sequence analysis indicated that the BADH gene contained 14 introns and the junction sequences at splicing sites followed the GT_AG rule basically.

关键词： spinach betaine aldehyde dehydrogenase genomic clone sequence analysis.

Pyramidal Edge Detection Method Based on AWFM Filtering and Fuzzy Linking Model

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High Technology Letters 2002年第1期8卷 26-31页

作者：王志刚 wangdong 等 SchoolofElectronics＆Information ShanghaijiaotongUniversityShanghai200030P.R.China

A novel multiresolution pyramidal edge detector, based on adaptive weighted fuzzy mean(AWFM)filtering and fuzzy linking model, is presented in this paper. The algorithm first constructs a pyramidal structure by repetitive AWFM filtering and subsampling of original image. Then it utilizes multiple heuristic linking criteria between the edge nodes of two adjacent levels and considers the linkage as a fuzzy model, which is trained offline. Through this fuzzy linking model, the boundaries detected at coarse resolution are propagated and refined to the bottom level from the coarse-to fine edge detection. The validation experiment results demonstrate that the proposed approach has superior performance compared with standard fixed resolution detector andprevious multiresolution approach, especially in impulse noise environment.

关键词： Edge detector Pyramidal structure Adaptive weight fuzzy mean filter Fuzzy modeling Impulse noise

Fault-Tolerant Design Techniques in ACMP Architecture

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 5-8页

作者： YAOWen.bin wangdong-sheng DepartmentofComputerScienceandTsinghuaUniversity Beijing100084China／／ResearchInstituteofInformationTsinghuaUniversityBeijing100084ChinaTechnologyTechnology ResearchInstituteofInformationTechnology TsinghuaUniversityBeijing100084China

Single-chip multiprocessor (CMP) combined with the fault-loleranl(FT)techniques offers an ideal architecture to achieve high availability on the basis of sustaining highcomputing performance FT design of a single-chip multiprocessor is described, including thetechniques from hard-wart redundancy to software support and firmware strategy. The design aims atmasking the influences of errors and automatically correcting the system states.

关键词： computer architecture fault-tolerant design single-chip multiprocessor