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Response Spectrum Analysis of 7-story Assembled Frame Structure with Energy Dissipation System

Structural Durability & Health Monitoring 2023年第2期17卷 159-173页

作者： jin Zhao yi wang Zhengwei Ma School of Civil and Transportation Engineering Henan University of Urban ConstructionPingdingshan467000China

Viscoelastic damper is an effective passive damping device,which can reduce the seismic response of the structure by increasing the damping and dissipating the vibration energy of *** has a wide application prospect in actual structural vibration control because of simple device and economical *** view of the poor seismic behaviors of assembled frame structure connections,various energy dissipation devices are proposed to improve the seismic *** finite element numerical analysis method is adopted to analyze relevant energy dissipation structural *** response spectrum of a 7-story assembled frame structure combined the ordinary steel support,ordinary viscoelastic damper,and viscoelastic damper with displacement amplification device is *** analysis results show that the mechanical behavior of assembled frame structure with ordinary steel supports are not significantly different from those without energy dissipation *** assembled frame structure with viscoelastic damper has better seismic performance and energy dissipation,especially for the viscoelastic damper with displacement amplification *** maximum value of inter-story displacement angle decreases by 32.24%;the maximum floor displacement decreases by 31.91%,and the base shear decreases by 13.62%compared with the assembled frame structures without energy dissipation *** results show that the seismic fortification ability of the structure is significantly improved,and the overall structure is more uniformly *** damping structure with viscoelastic damper mainly reduces the dynamic response of the structure by increasing the damping coefficient,rather than by changing the natural vibration period of the *** paper provides an effective theoretical basis and reference for improving the energy dissipation system and the seismic performance of assembled frame structures.

关键词： Assembled frame structure energy dissipation devices response spectrum analysis viscoelastic damper

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Stability analysis of n-species Lotka-Volterra almost periodic competition models with grazing rates and diffusions

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International Journal of Biomathematics 2014年第2期7卷 1-11页

作者： yi-jin Zhang Chang-You wang Institute of Applied MathematicsChongqing University of Posts and Telecommunications Chongqing 400065 P. R. China Key Laboratory of Industrial Internet of Things and Networked Control Ministry of Education Chongqing 400065 P. R. China

In this pape, almost periodic solution of a n-species Lotka-Volterra competition system with grazing rates and diffusions is investigated. By using the method of upper and lower solutions anti Schauder fixed point theorem as well as Lyapunov stability theory, we give sufficient conditions under which the strictly positive space homogeneous almost perilodic solution of the system is globally asymptotically stable. Moreover, some numerical simulations are given to validate our theoretical analysis.

关键词： Grazing rate competition model diffusion almost periodic solution stability.

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Identification of anti-cancer compounds from natural products

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Chinese Journal of Natural Medicines 2020年第7期18卷 481-482页

作者： LU jin-Jian wang yi-Tao State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China

Natural products serve as abundant resources with diversity of chemical structures,which has been widely explored for the pharmacological researches and drug discovery[1,2].They are generally isolated from microorgani... 详细信息

关键词： cancer abundant compounds

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Dynamic Weapon Target Assignment Based on Intuitionistic Fuzzy Entropy of Discrete Particle Swarm

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China Communications 2017年第1期14卷 169-179页

作者： yi wang jin Li Wenlong Huang Tong Wen State Key Laboratory of Astronautic Dynamics Xi'an 7 10043 China Northwest University School of Information and Technology Xi'an 710127 China Air Defense and Antimissile Institute Air Force Engineering University Xi'an 710051 China

Aiming at the problems of convergence-slow and convergence-free of Discrete Particle Swarm Optimization Algorithm(DPSO) in solving large scale or complicated discrete problem, this article proposes Intuitionistic Fuzzy Entropy of Discrete Particle Swarm Optimization(IFDPSO) and makes it applied to Dynamic Weapon Target Assignment(WTA). First, the strategy of choosing intuitionistic fuzzy parameters of particle swarm is defined, making intuitionistic fuzzy entropy as a basic parameter for measure and velocity mutation. Second, through analyzing the defects of DPSO, an adjusting parameter for balancing two cognition, velocity mutation mechanism and position mutation strategy are designed, and then two sets of improved and derivative algorithms for IFDPSO are put forward, which ensures the IFDPSO possibly search as much as possible sub-optimal positions and its neighborhood and the algorithm ability of searching global optimal value in solving large scale 0-1 knapsack problem is intensified. Third, focusing on the problem of WTA, some parameters including dynamic parameter for shifting firepower and constraints are designed to solve the problems of weapon target assignment. In addition, WTA Optimization Model with time and resource constraints is finally set up, which also intensifies the algorithm ability of searching global and local best value in the solution of WTA problem. Finally, the superiority of IFDPSO is proved by several simulation experiments. Particularly, IFDPSO, IFDPSO1~IFDPSO3 are respectively effective in solving large scale, medium scale or strict constraint problems such as 0-1 knapsack problem and WTA problem.

关键词： intuitionistic fuzzy entropy discrete particle swarm optimization algorithm 0-1 knapsack problem weapon target assignment

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Construction of oxygen vacancy on Bi_(12)O_(17)Cl_(2)nanosheets by heat-treatment in H_(2)O vapor for photocatalytic NO oxidation

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Journal of Materials Science & Technology 2022年第28期123卷 234-242页

作者： yi Yang yi Zeng Tongxin jin Xiaohu Zhang Huailong Teng Shengyao wang Hao Chen College of Science Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China

Oxygen-vacancies(OVs)play significant roles in semiconductor-based photocatalysis,such as elevating light absorption property,photogenerated carries separation efficiency,molecular activation,and photocatalytic ***,heat-treatment of semiconductors in dangerous H_(2)atmosphere is usually indispensable for OVs *** this work,C-doped Bi_(12)O_(17)C_(12)nanosheets were facially heat-treated in H_(2)O vapor(~2.3 vol%)mixed with Ar at 300℃to in-situ introduce OVs by the proposed reactions of C(s)+H_(2)O(g)→CO(g)+H_(2)(g)and H_(2)(g)+O_(Lattice)→H_(2)O(g)+*** formation of OVs,which was confirmed by electron paramagnetic resonance(EPR),can narrow the band gap,and enhance the photogenerated e~-/h~+separation efficiency on Bi_(12)O_(17)C_(12).Moreover,OVs-rich Bi_(12)O_(17)C_(12)nanosheets can facilitate molecular O_(2)activation and produce more reactive oxygen species(ROS),especially~1 O_(2),which greatly improve the NO to NO_(3)~-conversion efficiency with NO removal rate of~63%and NO_(3)~-production selectivity of~92.6%.The present work will bring new insights into the construction and roles of OVs in semiconductor-based photocatalysis.

关键词： Oxygen-vacancies H_(2)O vapor Photocatalytic NO oxidation ~1O_(2)

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Preparation of AlN thin films for film bulk acoustic resonator application by radio frequency sputtering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 464-470页

作者： Kan LI Hao jin De-miao wang yi-fei TANG Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Aluminum nitride （AlN） thin films with high c-axis orientation have been prepared on a glass substrate with an Al bottom electrode by radio frequency （RF） reactive magnetron sputtering. Based on the analysis of Berg＇s hysteresis model, the improved sputtering system is realized without a hysteresis effect. A new control method for rapidly depositing highly c-axis oriented AlN thin films is proposed. The N2 concentration could be controlled by observing the changes in cathode voltage, to realize the optimum processing condition where the target could be fixed stably in the transition region, and both stoichiometric film composition and a high deposition rate could be obtained. Under a 500 W RF power of a target with a 6 cm diameter, a substrate temperature of 450 ℃, a target-substrate distance of 60 mm and a N2 concentration of 25%, AlN thin film with preferential （002） orientation was deposited at 2.3 μm/h which is a much higher rate than previously achieved. Through X-ray diffraction （XRD） analysis, the full width at half maximum （FWHM） of AlN （002） was shown to be about 0.28°, which shows the good crystallinity and crystal orientation of AlN thin film. With other parameters held constant, any increase or decrease in N2 concentration results in an increase in the FWHM of AlN.

关键词： Aluminum nitride (A1N) Piezoelectric thin film Radio frequency (RF) reactive sputtering Preferred orientation,Film bulk acoustic resonator (FBAR)

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A method for pulsar searching:combining a two-dimensional autocorrelation profile map and a deep convolutional neural network

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Research in Astronomy and Astrophysics 2021年第7期21卷 155-170页

作者： Long-Qi wang jing jin Lu Liu yi Shen Department of Control Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In pulsar astronomy, detecting effective pulsar signals among numerous pulsar candidates is an important research topic. Starting from space X-ray pulsar signals, the two-dimensional autocorrelation profile map(2 D-APM) feature modelling method, which utilizes epoch folding of the autocorrelation function of X-ray signals and expands the time-domain information of the periodic axis, is proposed. A uniform setting criterion regarding the time resolution of the periodic axis addresses pulsar signals without any prior information. Compared with the traditional profile, the model has a strong anti-noise ability, a greater abundance of information and consistent characteristics. The new feature is simulated with double Gaussian components, and the characteristic distribution of the model is revealed to be closely related to the distance between the double peaks of the profile. Next, a deep convolutional neural network(DCNN)is built, named Inception-Res Net. According to the order of the peak separation and number of arriving photons, 30 data sets based on the Poisson process are simulated to construct the training set, and the observation data of PSRs B0531+21, B0540-69 and B1509-58 from the Rossi X-ray Timing Explorer(RXTE) are selected to generate the test set. The number of training sets and the number of test sets are 30 000 and 5400, respectively. After achieving convergence stability, more than 99% of the pulsar signals are recognized, and more than 99% of the interference is successfully rejected, which verifies the high degree of agreement between the network and the feature model and the high potential of the proposed method in searching for pulsars.

关键词： methods:data analysis methods:statistical X-rays:stars

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Structural Evolution During Mechanical Milling of Bimodal-Sized Al_2O_3 Particles Reinforced Aluminum Matrix Composite

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Acta Metallurgica Sinica(English Letters) 2018年第4期31卷 423-430页

作者： Ke Zhao Dan Tang jin-Ling Liu yi-Guang wang Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical University State Key Laboratory of Traction Power School of Mechanics and Engineering Southwest Jiaotong University Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province Southwest Jiaotong University

Hybrid aluminum matrix composite powders reinforced with bimodal-sized Al2O3 particles were synthesized by mechanical *** different approaches were investigated for the addition of submicron-and nano-sized Al2O3 particles to the aluminum powders,It was observed that the simultaneous addition of bimodal-sized Al2O3 particles to the aluminum powders resulted in an equiaxed morphology of the composite powders and the average particle size stabilized after 5 h of milling,indicating that the presence of bimodal-sized particles has greater effect on accelerating milling process as compared to nano-sized particles;the grain size of the aluminum matrix in composite powders was reduced to under 40 nm,approximate to the value obtained in the separate addition case,while a lower rate of refining was observed due to hindrance of submicron-sized particles on the interactions between nano-sized particles and the aluminum matrix.

关键词： Bimodal-sized Aluminum matrix composite Mechanical milling Grain refinement

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Online monitoring of water-soluble ionic composition of PM_(10)during early summer over Lanzhou City

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Journal of Environmental Sciences 2014年第2期26卷 353-361页

作者： jin Fan Xiaoying Yue yi jing Qiang Chen Shigong wang College of Atmospheric Science Lanzhou University College of Geography and Environment Northwest Normal University

Lanzhou is one of the most aerosol-polluted cities in China. In this study, an online analyzer for Monitoring for AeRosols and GAses was deployed to measure major water-soluble inorganic ions in PM10 at 1-hour time resolution, and 923 samples were obtained from Apr 1 to May 24, 2011. During the field campaign, air pollution days were encountered with Air Quality Index more than 100 and daily average concentration of PM10 exceeding 150 itg/m3. Based on the variation of water-soluble ions and results of Positive Matrix Factorization 3.0 model execution, the air pollution days were classified as crustal species- or secondary aerosol-induced, and the different formation mechanisms of these two air pollution types were studied. During the crustal species pollution days, the content of Ca2＋ increased and was about 2.3 times higher than the average on clear days, and the air parcel back trajectory was used to analyze the sources of crustal species. Data on sulfate, trace gases and meteorological factors were used to reveal the formation mechanism of secondary aerosol pollution. The sulfur oxidation ratio （SOR） was derived from the 923 samples, and the SOR had high positive correlation with relative humidity in early summer in Lanzhou.

关键词： particulate matter MARGA air pollution index Lanzhou

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PM-compact Graphs and Vertex-deleted Subgraphs

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Acta Mathematicae Applicatae Sinica 2022年第4期38卷 955-965页

作者： yi-pei ZHANG Xiu-mei wang jin-jiang YUAN School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

The perfect matching polytope of a graph G is the convex hull of the incidence vectors of all perfect matchings of G.A graph G is PM-compact if the 1-skeleton graph of the prefect matching polytope of G is ***,a matchable graph G is PM-compact if and only if for each even cycle C of G,G-V(C)has at most one perfect *** paper considers the class of graphs from which deleting any two adjacent vertices or nonadjacent vertices,respectively,the resulting graph has a unique perfect *** PM-compact graphs in this class of graphs are presented.

关键词： perfect matching nice cycle bicritical graph PM-compact graph

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