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Effect Comparison on Forecasting of High-Frequency Time Series by non-linear analysis

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Effect Comparison on Forecasting of High-Frequency Time Seri...

Multi-scale analysis of flow structures in fluidized beds with immersed tubes

第十五届工业工程与工程管理国际会议

作者： Huang Fengwen~1 Zhang Bao~2 yin 1 Research Center of Finance Urban Management College of Shanghai Shanghai P.R.China 200233 2 Management School Tianjin University Tianjin P.R.China 300072

＜正＞In order to obtain the predictability of high-frequency time series,this paper develops state space reconstruction and divergence calculation techniques have been for t+1 temporal trend of stock index,state space reconstruction technique preserve certain information on original time series which describes the asymptotic behavior of *** describing the asymptotic behavior,the properties of the system will be shown better when the time t is large enough. Divergence calculation of dynamical system is used to describe the characterization of system and analyze the temporal *** divergence is locally equivalent to the trace of the Jacobian and measures the rate of the change of an infinitesimal state space volume V（t） following an orbit x（t）.In this paper,we forecast the t+1 temporal of Shanghai stock market composite index based on 5-minute high-frequency time series and get a satisfying result.

关键词： non-linear analysis State Space Reconstruction Divergence Calculation Transaction Cost Forecasting

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Particuology 2015年第4期13卷 99-106页

作者： Hamid R.Norouzi Maryam Tahmasebpoor Reza Zarghami Navid Mostoufi Multiphase Systems Research Lab.School of Chemical Engineering College of EngineeringUniversity of Tehran Department of Chemical and Petroleum Engineering University of Tabriz

Multi-scale analysis and non-linear analysis were combined to investigate the hydrodynamics of fluidized beds with and without horizontal tubes. Pressure fluctuations were measured and analyzed employing discrete wavelet analysis, recurrence plot analysis, and recurrence quantification analysis. A systematic procedure was followed to determine wavelet parameters. At low gas velocities, the energy of macro-structures reduces with the addition of the first tube and then increases with the addition of a second tube. However, there is no notable difference at high gas velocities. Determinism is high for the bed without tubes, which can be attributed to the periodic behavior of bubbles. Determinism decreases with the addition of tubes because the breakage of bubbles results in less periodic behavior. The three methods of analysis used in this study captured the effects of immersed tubes on the hydrodynamics of fluidized beds. Recurrence quantitative analysis was found to be a powerful and easy-to-use method that can capture the nonlinear characteristics of fluidized beds much more quickly than conventional methods of nonlinear analysis. This method can thus be effectively used for the online monitoring of hydrodynamic changes in fluidized beds.

关键词： Immersed tube non-linear analysis Pressure fluctuations Recurrence plot Wavelet transform

Assessment of Seismic Damage in Nativity Church in Bethlehem Using Pushover analysis

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Structural Durability & Health Monitoring 2021年第4期15卷 349-366页

作者： Belal Almassri Ali Safiyeh Civil and Architectural Engineering Department College of EngineeringPalestine Polytechnic UniversityHebronPalestine Civil Engineering Department Faculty of EngineeringNajjah National UniversityNablusPalestine

This study focuses on advanced finite element(FE)analyses on The Church of Nativity located in Bethlehem(Palestine),one of the most historic structures in the *** ensure the model quality,a 3D FE model was created using two types of typical commercial software,DIANA FEA and *** analyses,one of the expected behaviors for this kind of masonry structure“low modal period”was *** seismic behavior of the church was studied using pushover analyses,which were conducted using DIANA *** first unidirectional mass proportional load pattern was created in both directions,X-direction as a longitudinal direction and Y-direction as the transversal *** incremental iterative procedure was used with monotonically increasing horizontal loads,using constant gravity *** results showed that the transversal direction is the most vulnerable and the damage concentrates at the main lateral(longitudinal)walls,mainly at the south and north alignment walls,and also at the vaults and at the connections of the vaults to the *** width was at the upper limit in the in-plane direction(X-direction).While,in Y-direction,it exceeded the limits of IBC code in width and length with a maximum width of 13.7 mm.A more accurate nonlinear dynamic analysis is recommended in the near future,which takes into account the material nonlinearity for more reasonable seismic behavior simulation.

关键词： Masonry seismic assessment FE model non-linear analysis DIANA FEA SAP 2000

THE　MATHEMATICAL　MODELS　AND　GENERALIZED　VARIATIONAL　PRINCIPLES　OF　nonlinear　analysis　FOR　PERFORATED　THIN　PLATES

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Applied Mathematics and Mechanics(English Edition) 1996年第2期17卷 109-118页

作者：程昌钧杨骁 Department of Mechanics Lanzhou University Lanzhou Gansu P. R. China

On foe basis of the Kirchoff-Karman hypothses for the nonlinear bending of thin plates, the three kinds of boundary value problems of nonlinear analysis for perforated fhin plates are presented under the differenr in-plane boundary conditions and the corresponding generalized varialional principles are established. One can see that all mathematical models presented in this paper are completely new ones and differ from the ordinary von Karman theory. These mathematical models can be applied to the nonlinear analysis and the Stability analysis of perforaled thin plates in arbitraryplane boundary conditions.

关键词： perforated thin plate non-linear analysis mathematical model generalized variational principle

Formulation of Reduction Rate for Ultimate Compressive Strength of Stiffened Panel Induced by Opening

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China Ocean Engineering 2014年第4期28卷 557-568页

作者：于昌利 LEE Joo-sung School of Naval Architecture and Ocean Engineering Harbin Institute of Technology School of Naval Architecture and Ocean Engineering University of Ulsan

The main objective of this study is to numerically investigate the characteristics of ultimate compressive strength of stiffened panels with opening and also to fit the design-oriented formulae. For this purpose, three series of well executed experimental data on longitudinally stiffened steel plates with and without opening subjected to the uniform axial in-pane load which is carried out to study the buckling and post-buckling up to the final failure are chosen. Also, a nonlinear finite element method capable of efficiently analyzing the large elasto-plastic deflection behavior of stiffened panels is developed and used for simulation. The feasibility of the present simulation process is confirmed by a good agreement with the experimental results. More case studies are developed employing the simulation process to analyze the influence of various design variables on the reduction rate of ultimate strength of stiffened panel induced by opening. Based on the computed results, two design formulae are fitted and the accuracy of design formulae is studied. Furthermore, the viability of the design formulae for practical engineering is proved.

关键词： stiffened panel opening reduction rate non-linear analysis formulae fitting

nonlinear finite element analysis of three implant-abutment interface designs

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International Journal of Oral Science 2012年第2期4卷 101-108页

作者： Chun-Bo Tang Si-Yu Liu Guo-Xing Zhou Jin-Hua Yu Guang-Dong Zhang Yi-Dong Baot Qiu-Ju Wang Dental Research Institute Nanjing Medical University Nanjing China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics

The objective of this study was to investigate the mechanical characteristics of implant-abutment interface design in a dental implant system, using nonlinear finite element analysis （FEA） method. This finite element simulation study was applied on three commonly used commercial dental implant systems： model I, the reduced-diameter 3i implant system （West Palm Beach, FL, USA） with a hex and a 12-point double internal hexagonal connection; model II, the Semados implant system （Bego, Bremen, Germany） with combination of a conical （45° taper） and internal hexagonal connection; and model III, the Br,~nemark implant system （Nobel Biocare, Gothenburg, Sweden） with external hexagonal connection. In simulation, a force of 170 N with 45°oblique to the longitudinal axis of the implant was loaded to the top surface of the abutment. It has been found from the strength and stiffness analysis that the 3i implant system has the lowest maximum yon Mises stress, prirlcipal stress and displacement, while the Br^nemark implant system has the highest. It was concluded from our preliminary study using nonlinear FEA that the reduced-diameter 3i implant system with a hex and a 12-point double internal hexagonal connection had a better stress distribution, and produced a smaller displacement than the other two implant systems.

关键词： external hexagonal connection finite element analysis implant-abutment interface internal hexagonal connection non-linear analysis

A geometry characteristic of Banach spaces with c^1-norm

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Frontiers of Mathematics in China 2014年第5期9卷 1089-1103页

作者： Jipu MA Department of Mathematics Nanjing University Nanjing 210093 China

Let E be a Banach space with the cl-norm｜｜·｜｜ in E／{0}, and let S（E） = {e ∈ E：｜｜e｜｜ = 1}. In this paper, a geometry characteristic for E is presented by using a geometrical construct of S（E）. That is, the following theorem holds： the norm of E is of eI in E／{0} if and only if S（E） is a c1 submanifold of E, with codimS（E） = 1. The theorem is very clear, however, its proof is non-trivial, which shows an intrinsic connection between the continuous differentiability of the norm ｜｜·｜｜ in E／{0} and differential structure of S（E）.

关键词： Banach space geometry non-linear analysis global analysis