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Structural modal parameter identifi cation and damage diagnosis based on Hilbert-Huang transform

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 101-111页

作者： Han jianping Zheng Peijuan Wang Hongtao Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province Lanzhou University of Technology

Traditional modal parameter identifi cation methods have many disadvantages,especially when used for processing nonlinear and non-stationary *** addition,they are usually not able to accurately identify the damping ratio and *** this study,methods based on the Hilbert-Huang transform(HHT) are investigated for structural modal parameter identifi cation and damage ***,mirror extension and prediction via a radial basis function(RBF) neural network are used to restrain the troublesome end-effect issue in empirical mode decomposition(EMD),which is a crucial part of ***,the approaches based on HHT combined with other techniques,such as the random decrement technique(RDT),natural excitation technique(NExT) and stochastic subspace identifi cation(SSI),are proposed to identify modal parameters of ***,a damage diagnosis method based on the HHT is also ***-varying instantaneous frequency and instantaneous energy are used to identify the damage evolution of the *** relative amplitude of the Hilbert marginal spectrum is used to identify the damage location of the ***,acceleration records at gauge points from shaking table testing of a 12-story reinforced concrete frame model are taken to validate the proposed *** results show that the proposed approaches based on HHT for modal parameter identifi cation and damage diagnosis are reliable and practical.

关键词： modal parameter identifi cation damage diagnosis Hilbert-Huang transform natural excitation technique stochastic subspace identifi cation random decrement method shaking table test

Numerical Investigation on Fluid Structure Interaction Considering Rotor Deformation for a Centrifugal Pump

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 539-545页

作者： YUAN Shouqi PEI Ji YUAN jianping Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

The existing research for unsteady flow field and the corresponding flow induced vibration analysis of centrifugal pump are mainly carried out respectively without considering the interaction between fluid and structure. The ignorance of fluid structure interaction （FSI） means that the energy transfer between fluid and structure is neglected. To some extent, the accuracy and reliability of unsteady flow and rotor deflection analysis should be affected by this interaction mechanism. In this paper, a combined calculation between two executables for turbulent flow and vibrating structure was established using two-way coupling method to study the effect of FSI. Pressure distributions, radial forces, rotor deflection and equivalent stress are analyzed. The results show that the FSI effect to pressure distribution in flow field is complex. The pressure distribution is affected not only around impeller outlet where different variation trends of pressure values with and without FSI appear according to different relative positions between blade and cutwater, but also in the diffusion section of volute. Variation trends of peak values of radial force amplitude calculated with and without FSI are nearly same under high flow rate and designed conditions while the peak value with FSI is slightly smaller, and differently, the peak value with FSI is larger with low flow rate. In addition, the effect of FSI on the angle of radial force is quite complex, especially under 0.5Q condition. Fluctuation of radial deflection of the rotor has obvious four periods, of which the extent is relatively small under design condition and is relatively large under off-design condition. Finally, fluctuations of equivalent stress with time are obvious under different conditions, and stress value is small. The proposed research establishes the FSI calculation method for centrifugal pump analysis, and ensures the existing affect by fluid structure interaction.

关键词： centrifugal pump fluid structure interaction coupled solution unsteady turbulent flow basic theory

Integrated parallel forecasting model based on modified fuzzy time series and SVM

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Journal of Systems Engineering and Electronics 2017年第4期28卷 766-775页

作者： Yong Shuai Tailiang Song jianping Wang Technical Support Engineering Faculty Academy of Armored Forced Engineering Beijing 100072 China Unit 68207 of the PLA Jiayuguan 735100 China China Defense Science & Technology Information Center Beijing 100142 China

A dynamic parallel forecasting model is proposed, which is based on the problem of current forecasting models and their combined model. According to the process of the model, the fuzzy C-means clustering algorithm is improved in outliers operation and distance in the clusters and among the clusters. Firstly, the input data sets are optimized and their coherence is ensured, the region scale algorithm is modified and non-isometric multi scale region fuzzy time series model is built. At the same time, the particle swarm optimization algorithm about the particle speed, location and inertia weight value is improved, this method is used to optimize the parameters of support vector machine, construct the combined forecast model, build the dynamic parallel forecast model, and calculate the dynamic weight values and regard the product of the weight value and forecast value to be the final forecast values. At last, the example shows the improved forecast model is effective and accurate.

关键词： fuzzy C-means clustering fuzzy time series interval partitioning support vector machine particle swarm optimization algorithm parallel forecasting

New chaotic system and its hyperchaos generation

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1179-1187页

作者： Bao Bocheng Liu Zhong Xu jianping Dept. of Electronic Engineering Nanjing Univ. of Science and Technology Nanjing 210094 P. R. China School of Electrical and Information Engineering Jiangsu Teachers Univ. of Technology Changzhou 213001 P. R. China School of Electrical Engineering Southwest Jiaotong Univ. Chengdu 610031 P. R. China

To seek for lower-dimensional chaotic systems that have complex topological attractor structure with simple algebraic system structure, a new chaotic system of three-dimensional autonomous ordinary differential equations is presented. The new system has simple algebraic structure, and can display a 2-scroll attractor with complex topological structure, which is different from the Lorenz＇s, Chen＇s and Lu¨＇s attractors. By introducing a linear state feedback controller, the system can be controlled to generate a hyperchaotic attractor. The novel chaotic attractor, hyperchaotic attractor and dynamical behaviors of corresponding systems are further investigated by employing Lyapunov exponent spectrum, bifurcation diagram, Poincar′e mapping and phase portrait, etc., and then verified by simulating an experimental circuit.

关键词： chaotic system attractor chaos hyperchaos.

Novel C15 sesquiterpanes and their origin in different crude oils from the Pearl River Mouth Basin of China

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Science China Earth Sciences 2016年第8期59卷 1622-1632页

作者： BAO jianping CHEN XiWen ZHU CuiShan Key Laboratory of Oil&Gas Resource and Exploration Technology Geochemistry DepartmentYangtze UniversityWuhan 430100China

In the saturate fractions of crude oils from the Zhu1 and Zhu2 depressions of the Pearl River Mouth Basin,two novel C_(15) sesquiterpanes have been detected except for drimanes and rearranged *** comparison with spectra and retention times in previous studies,they have been identified as 2,2,4α,7,8-pentamethyl-trans-decalin and 2,2,4α,7,8-pentamethyl-cis-decalin,respectively,which are related to the D/Eringsof18α(H)-and18β(H)-***15sesquiterpanesarerelativelyabundantincondensateoilsthathavehighPr/PhratiosandarerichinterrigenoustriterpanessuchasoleananeandbicadinanesfromtheZhu2depression,butevidentlylowinlacustrineoilsthathavelowPr/***15sesquiterpanescouldberelatedtoterrigenousorganicmatterinorigina***,thereexistcompletelydifferentcorrelationsbetweentherelativeabundancesofdifferentC15sesquiterpanesthathavedifferentsourcesandthePr/Phratio,***,thenovelC15sesquiterpanesandcadinanethatindicateterrigenousinputarepositivelycorrelatedwiththePr/Phratio,butdrimanesandrearrangeddrimaneshavingmicrobialoriginarenegativelycorrelatedwiththePr/******15sesquiterpanesaremuchmoreabundantincarbonaceousmudstone(Pr/Ph=7.39)thanindarkmudstone(Pr/Ph=2.19)fromtheEnpingformation,***,theyarenotcommoninsapropeliclacustrinesourcerocks(Pr/Ph=2.29)***ition,butanoxicenvironmentduringdepositionanddiagenesismaybeaprerequisitefortheformationofnovelC15sesquiterpanes.

关键词： Sesquiterpanes Drimanes Cadinane Oleanane Bicadinanes Crude oils Pearl River Mouth Basin

Degradation of 4-nitrophenol by electrocatalysis and advanced oxidation processes using Co3O4@C anode coupled with simultaneous CO2 reduction via SnO2/CC cathode

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Chinese Chemical Letters 2020年第7期31卷 1961-1965页

作者： meng Zhu Longshuai Zhang Shanshan Liu Dengke Wang Yuancheng Qin Ying Chen Weili Dai Yuehua Wang Qiuju Xing jianping Zou Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China

Herein,we prepa red novel three-dimensional(3D)gear-s haped Co3O4@C(Co3O4 modified by amorphous carbon)and sheet-like SnO2/CC(SnO2 grow on the carbon cloth)as anode and cathode to achieve efficient removal of 4-nitrophenol(4-NP)in the presence of peroxymonosulfate(PMS)and simultaneous electrocatalytic reduction of CO2,*** this process,4-NP was mineralized into CO2 by the Co3O4@C,and the generated CO2 was reduced into HCOOH by the sheet-like SnO2/CC *** with the pure Co0.5(Co3O4 was prepared using 0.5 g urea)with PMS(30 mg,0.5 g/L),the degradation efficiency of 4-NP(60 mL,10 mg/L)increased from 74.5%-85.1%in 60 min using the Co0.5 modified by amorphous carbon(Co0.5@C).Furthermore,when the voltage of 1.0 V was added in the anodic system of Co0.5@C with PMS(30 mg,0.5 g/L),the degradation efficiency of 4-NP increased from 85.1%-99.1%when Pt was used as *** the experiments of 4-NP degradation coupled with simultaneous electrocatalytic CO2 reduction,the degradation efficiency of 4-NP was 99.0%in the anodic system of Co0.5@C with addition of PMS(30 mg,0.5 g/L),while the Faraday efficiency(FE)of HCOOH was 24.1%at voltage of-1.3 V using the SnO2/CC as *** results showed that the anode of Co3O4 modified by amorphous carbon can markedly improve the degradation efficiency of 4-NP,while the cathode of SnO2/CC can greatly improve the FE and selectivity of CO2 reduction to HCOOH and the stability of ***,the promotion mechanism was proposed to explain the degradation of organic pollutants and reduction of CO2 into HCOOH in the process of electrocatalysis coupled with advanced oxidation processes(AOPs)and simultaneous CO2 reduction.

关键词： Advanced oxidation processes CO2 reduction Degradation Electrocatalytic oxidation Sulfate radical

Progress of continuously rotating detonation engines

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Chinese Journal of Aeronautics 2016年第1期29卷 15-29页

作者： Zhou Rui Wu Dan Wang jianping Center for Combustion and Propulsion College of Engineering Peking University Center for Applied Physics and Technology Peking University State Key Laboratory for Turbulence & Complex Systems Peking University

Continuously rotating detonation engine （CRDE） is a focus for concern in the field of aerospace propulsion. It has several advantages, including one-initiation, high thermal efficiency and simple structure. Due to these characteristics, it is expected to bring revolutionary advance- ments to aviation and aerospace propulsion systems and now has drawn much attention throughout the world. In this paper, an overview of the development of CRDE is given from several aspects： basic concepts, applications, experimental studies, numerical simulations, and so on. Representative results and outstanding contributions are summarized and the unresolved issues for further engi- neerin~ applications of CRDE are 13rovided.

关键词： Aerospace Continuously rotatingdetonation CRDE Detonation engine Propulsion system

Increased-diversity systematic resampling in particle filtering for BLAST

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Journal of Systems Engineering and Electronics 2009年第3期20卷 493-498页

作者： Zheng jianping Bai Baoming Wang Xinmei State Key Laboratory of Integrated Services Networks Xidian Univ. Xi'an 710071 P. R. China

Two variants of systematic resampling （S-RS） are proposed to increase the diversity of particles and thereby improve the performance of particle filtering when it is utilized for detection in Bell Laboratories Layered Space-Time （BLAST） systems. In the first variant, Markov chain Monte Carlo transition is integrated in the S-RS procedure to increase the diversity of particles with large importance weights. In the second one, all particles are first partitioned into two sets according to their importance weights, and then a double S-RS is introduced to increase the diversity of particles with small importance weights. Simulation results show that both variants can improve the bit error performance efficiently compared with the standard S-P^S with little increased complexity.

关键词： systematic resampling particle filtering Markov chain Monte Carlo Bell Laboratories Layered Space- Time (BLAST).

Ligand-dependent aggregation-enhanced photoacoustic of atomically precise metal nanocluster

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Aggregate 2024年第1期5卷 196-203页

作者： Changlin Zhou meng Wang Qiaofeng Yao Yu Zhou Chuantao Hou Jianfei Xia Zonghua Wang Jishi Chen jianping Xie College of Chemistry and Chemical Engineering Shandong Sino-Japanese Center for Collaborative Research of Carbon NanomaterialsInstrumental Analysis Center of Qingdao UniversityQingdao UniversityQingdaoP.R.China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjinP.R.China Qingdao Boting Hydrogen Age Ocean Technol R&D Ctr. Qingdao Boting Technol Co.Ltd.Shandong Hydrogen Times Marine Technology Co.Ltd.QingdaoP.R.China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhouP.R.China

Atomically precise metal nanoclusters(MNCs),as a potential type of photoacoustic(PA)contrast agent,are limited in application due to their low PA conversion efficiency(PACE).Here,with hydrophilic Au25SR18(SR=thiolate)as model NCs,we present a result that weakly polar solvent induces aggregation,which effectively enhances PA intensity and *** PA intensity and PACE are highly dependent on the degree of aggregation,while the aggregation-enhanced PA intensity(AEPA)positively correlates to the protected *** an AEPA phenomenon indicates that aggregation actually accelerates the intramolecular motion of Au NCs,and enlarges the proportion of excited state energy dissipated through vibrational *** result conflicts with the restriction of intramolecular motion mechanism of aggregation-induced *** experiments show that the increased energy of AEPA originates from the aggregation inhibiting the intermolecular energy transfer from excited Au NCs to their surrounding medium molecules,including solvent molecule and dissolved oxygen,rather than restricting radiative *** study develops a new strategy for enhancing the PA intensity of Au NCs,and contributes to a deeper understanding of the origin of the PA signal and the excited state energy dissipation processes for MNCs.

关键词： aggregation-enhanced photoacoustic gold nanocluster intermolecular excited state energy transfer intramolecular motion ligand effect