Abstract
This paper aims to solve two problems of the sandwich panel with aluminum honeycomb: material parameters solution and shape control. The accurate material parameters of the sandwich panels are the basis of shape control. Therefore, a mixed numerical-experimental method is proposed to inversely solve equivalent material parameters of the sandwich panel using genetic algorithm (GA) in the first place. Then a high efficiency FE model based on equivalent material parameters is established to study shape control of the sandwich panels. For shape control, the key issue aims to search optimum position and adjustment volume of control points where actuators are installed. Toward the end, the FE simulation method is deployed to optimize actuator position and adjustment volume one by one. Finally, an active control platform based on multi-point adjustment is developed to verify the practicability of the approach proposed in this paper. Through the experiment of shape control, the root mean square (RMS) of surface deviation of sandwich panel is decreased from 62.7μm to 15.5μm. The results show that the shape control can significantly improve the surface accuracy of the sandwich panels, and the validity of equivalent material parameters is also proved from the side.
1 Introduction
The sandwich panels with aluminum honeycomb, for their advantages of light weight, high rigidity, great intensity and good electrical property, have been widely used in fabrication of the reflectors for microwave communication equipment, such as compact antenna test range (CATR), radio telescope, millimeter-wave radar, etc. The sandwich panels obtained by vacuum flexible forming proposed by professor ZHOU (Beihang University) have been successfully applied in fabrication of the reflectors for many CATRs [1, 2, 3]. Although these sandwich panels obtained from this forming process provides high-precision surface, it cannot satisfy high-precision requirements of the reflector panels when the working frequency is 110GHz or higher. According to American construction standards of the CATR, the RMS value of the surface deviation of reflector panels should be better than one percent of wave length corresponding to working frequency [4, 5]. Therefore, it is very meaningful to study the method of further improving surface precision of the sandwich panels for expanding application scope and reducing scrap rate.
In recent years, a large number of investigations have focused on improving precision and controlling shape of the reflectors used in microwave communication equipment. Washington et al [6, 7] investigated the optimization method of mechanically reconfigurable aperture antennas. A method termed as greatest error suppression method was proposed to optimize actuator position and actuation value. Theunissen et al [8] developed a mechanical FE code that is incorporated into a diffraction synthesis code to enable direct synthesis of a reconfigurable dual offset reflector antenna contour beam in terms of the actuator amplitudes and positions. Ray M C. et al [9, 10] conducted investigations on the active control of geometrically

Geometric size of the sandwich panels with regular hexagonal honeycomb
nonlinear vibrations of doubly curved smart sandwich shells and functionally graded laminated composite shells using 1-3 piezoelectric composites. A three dimensional FE model was developed to study this coupled nonlinear electro-elastic problem. Wang et al [11] established the FE model of the active structure with PZT actuator to adjust the shape profile of cable net structures. The optimal actuation voltages for the desired shape were evaluated by the quadratic criterion and min-max scheme respectively. The above approaches of shape control are more suitable to ameliorate surface precision of the panels fabricated by piezoelectric materials or weak rigidity plates. However, the sandwich panels involved in this study are made of ordinary aluminum plates and honeycombs, and this structure has a relatively high stiffness. It is very difficult to greatly improve and chronically ensure high-precision of the surface for sandwich panels just using the above method. Throughout these investigations, the key issues of shape control mainly involve two aspects: position optimization and adjustment optimization of the control points. Therefore, the FE method is deployed to optimize actuator position and adjustment volume for shape control of sandwich panels.
It is the first prerequisite to establish an accurate FE model of sandwich panels during FE analysis of shape control. Considering the computational efficiency, the honeycomb core must be equivalently modeled in actual engineering analysis. Wherefore, how to obtain effective material parameters plays an extremely important role in FE analysis of shape control. For similar materials, large numbers of investigations have focused on solving their parameters. A high-efficiency method of mixed numerical-experimental was proposed to estimate material parameters in 1990s [12, 13]. With the development of optimization algorithm and computer technology, the methodology is frequently employed to inversely seek mechanical and thermal properties of composite panels [14, 15], not only for homogeneous materials, but also anisotropic materials, such as laminated plates [16], sandwich panels [17, 18] and functional composite materials [19]. Based on the analysis of these researches, a mixed numerical-experimental method using GA will be investigated to evaluate material parameters of the sandwich panel with aluminum honeycomb.
As mentioned above, this study mainly focuses on two issues: material parameter solution of honeycomb cores and shape control of sandwich panels. Firstly, a mixed numerical-experimental method using GA is established to inversely solve equivalent material parameters of the sandwich panel based on stiffness experiment by four-point supporting and center loading. Then, the FE simulation method is deployed to optimize actuator position and adjustment volume for shape control of sandwich panels. The final meaningful work is to develop an active control platform based on multi-point adjustment to verify the practicability of the shape control for improving surface precision of the sandwich panel.
2 Methodology Formulation
2.1 Equivalent FE model of sandwich panels
The panel fabricated by vacuum flexible forming has a sandwich structure constituted of three-layer aluminum plates and two-layer aluminum honeycombs which are tightly spliced by enhanced epoxy glue [2]. Figure 1 shows the sketchy structure and key dimensions (a, b, h1, h2, h3, h4, h5) of the panel. According to the different analysis objectives, there are many different equivalent modeling methods for sandwich panels with aluminum honeycomb. In order to improve the calculation efficiency, most of the finite element models of sandwich panels use two-dimensional shell units [20]. However, this modeling method cannot achieve the analysis requirements in this paper. In order to meet the analysis requirements of shape control, the equivalent FE model of sandwich panels is established based on sandwich panel theory. The three-layer aluminum plates are modeled as homogeneous isotropic shell with the same thickness as h1, h2 and h3. The two-layer honeycomb cores are equivalent to a homogeneous orthotropic solid with the same thickness as h4 and h5. The aluminum plate is meshed by a quadrilateral shell element (S4R), and the honeycomb core is meshed by a three-dimensional solid element (C3D8R) [21, 22], and the contact surface constraint type between the aluminum plate and the honeycomb core is tie. The equivalent FE model of the sandwich panel is shown in Figure 2.

The equivalent FE model of the sandwich panels
2.2 Inverse solution method of material parameters
In the equivalent FE model of sandwich panels, the material parameters of the three-layer aluminum panels are obvious. However, the equivalent parameters of honeycomb core are relatively incomparable. In order to obtain these equivalent parameters, a mixed numerical-experimental method is proposed to inversely solve them using GA. Toward this end, stiffness experiment of sandwich panels is designed by four-point supporting and center loading.
Load zone, supporting position (S1∼S4) and sample points (1∼16) are shown in Figure 3. Due to the symmetry of the stiffness experiment, sample points are selected in a quarter area of the panel, and the choice of sixteen sample points is considered from the maximum deformation position to the minimum deformation position. Similarly, the corresponding FE analysis model of the stiffness experiment is established using the ABAQUS software. The deformation of the sample points can be respectively obtained by experiment and FE simulation. The deformation value obtained by the FE simulation can be made incomparably close to the experimental value by modifying the material parameters of the equivalent honeycomb core. The solution process is actually a Single-objective multivariate optimization problem. The GA is very suitable for solving this kind of problem, because of the advantage of global, robustness, universality and expandability.

Load zone, support position and sample points of stiffness experiment
The effective Young’s module, shear module and Poisson’s ratio of the equivalent honeycomb core as optimization variables, as shown in equation (1).
The experiment and simulation value of deformation at sample points are used to model the objective function f(X) as:
Where δi is the experiment value of the deformation of the i-th sample point,
The optimization process is divided into forward analysis and inverse analysis. For the forward analysis, FE model is established for stiffness experiment of sandwich panels which the equivalent material parameters are estimated. For the inverse analysis, the GA method is employed to optimize and iterate the variable of material parameters according to the deviation between experiment value and simulation value. In order to improve the efficiency of parameter optimization, the GA method and FE analysis is seamlessly encapsulated by iSIGHT software. The optimization process of solution does not require human intervention, such as parameters modification, job creation, task submission, etc., which can greatly improve the efficiency of calculation. This routing optimization of reversing material parameters of this kind of sandwich panels is shown in Figure 4.

Inverse solution flow-chart for equivalent material parameters of honeycomb core
2.3 Optimization method of shape control
In this section, two optimization problems are solved: actuator position optimization and adjustment volume optimization. The geometric model truly reflecting actual error of the sandwich panel is firstly reconstructed as FE model according to the point-cloud data measured by laser tracker (Leica AT901-B). The maximum deviation will be chosen as corresponding position and adjustment of the first actuator. The comparison is done by imposing the displacement identical to the max error value on the reconstructed geometric model to force it into taking the shape of the designed CAD at the position with the max deviation. After the first simulation, the node coordinates on the surface of the panel are output to a file. And then, the RMS value and maximum deviation of the adjusted surface are calculated according to the file. The aforementioned simulation process is repeated again and again until obtaining the desired RMS value of the surface error. The whole optimization process of the actuator position and actuation value is illustrated in Figure 5.

Optimization process flow-chart of shape control
3 Results and discussion
3.1 Equivalent material parameters
The geometric size of the specimen used to solve the equivalent material parameters of the honeycomb core are followed as: a = 2450mm, b = 1305mm, h1 = h3 = 1.5mm, h2 = 1.0mm, h4 = h5 = 48mm, lc = 5.0mm and tc = 0.04mm.
The specification of the three-layer aluminum plate is YL12CZO, whose elastic modulus is 70000Mpa and poisson’s ratio is 0.33. The honeycomb cell is a regular hexagon with aluminum alloy 5052. Stiffness experiment based on four-point supporting and center loading is shown in Figure 6, and the deformation of sample points is measured by laser tracker. At the beginning of inversing equivalent materials, the initial value and feasible value range of the design variables are determined by theoretical explanation [23], as shown in Table 1.

Stiffness experiment of the sandwich panels
Initial value and feasible domain of equivalent material properties
Young’s modulus/MPa | Shear modulus / MPa | Poisson ratio | |||||||
---|---|---|---|---|---|---|---|---|---|
Ecx | Ecy | Ecz | Gcxy | Gcxz | Gcyz | ucxy | ucxz | ucyz | |
Initial value | 0.09 | 0.09 | 886.8 | 0.02 | 124.7 | 124.7 | 0.33 | – | – |
Feasible domain | 0∼2000 | 0∼500 | 0.1∼0.5 |
The exactly equivalent material parameters of the panel are obtained through the optimization process shown in Figure 4. During the inverse seeking, elitist strategy is adopted, the mutation rate is set at 1% and the crossover rate is set at 8%. The convergence history of the synthesis algorithm is displayed in Figure 7. It is evident that the optimal solution is obtained when the GA procedures run for 1000 generations with objection better than 2.9um. At this time, the equivalent material parameters of honeycomb core are optimized and solved through mixed numerical-experimental method, as listed in Table 2. In order to prove the reliability of equivalent parameters, experiment and simulation results are separately compared under bearing load 100N, 200N, 300N and 400N. The comparison curves between experiment and simulation results are respectively drawn in Figure 8. As known from Figure 8, the dispersion between the simulated and experimental values is larger at low loads. A possible reason is that there is a system error in the stiffness experiment, such as measurement uncertainty. The deformation amount of the sample points increases with the load increasing, however the system error may be constant. The ratio of the system error to the deformation is decreasing with the load increasing. Excepting this situation, the consistent between experiment and simulation is quite high. The stiffness experiment results show that the equivalent model of the sandwich panel is effective, and the solution of the equivalent material parameters of the honeycomb core is accurate.

Convergence history of material parameters reverse solution using GA

Results comparison between experiment and simulation bearing load 100N (a), 200N (b), 300N (c) and 400N (b)
Optimized equivalent material parameters of honeycomb core
Young’s modulus / MPa | Shear modulus / MPa | Poisson ratio | |||||||
---|---|---|---|---|---|---|---|---|---|
Ecx | Ecy | Ecz | Gcxy | Gcxz | Gcyz | ucxy | ucxz | ucyz | |
Equivalent value | 0.136 | 0.136 | 975.5 | 0.06 | 118.47 | 118.47 | 0.34 | 0 | 0 |
3.2 Shape control of sandwich panels
On the basis of equivalent material model, FE Analysis example of shape control for the sandwich panel is carried out. The experiment piece used for the shape control has the same geometry as that of stiffness test. The deviation between the actual surface and the theoretical surface is measured and calculated by laser tracker system (Leica AT901-B). The RMS of surface deviation is 0.0627mm with max error 0.178mm and min error-0.142mm, as shown in Figure 9.

Surface deviation distribution of experimental piece
In the first place, FE simulation of shape control process for the specimen is carried out. From Figure9 it can be found that the initial maximum deviation occurs at the four corners of the sandwich panel. Therefore, the first simulation of the shape control for the panel is done by imposing respective displacement on the four corners of the model. After the first adjustment, the surface precision (RMS value) of the panel is improved from 0.0627mm to 0.038mm, and the peak-to-peak value of the deviation is ameliorated from 0.320mm to 0.138mm. The actuator position and error distribution of the panel surface after the first adjustment is shown in Figure 10.

Actuator position (a) and error distribution (b) of the sandwich panel after first adjustment
Although the surface precision of the panel has been greatly improved through the first adjustment, it still does not meet the target precision. And therefore, another adjustment is needed. The second adjustment is conducted under the results of the first simulation. The four control points of the first regulation should be set as fixed constraint along z-direction of the panel. The second simulation is executed by imposing actuator value at the middle position of the two long sides. The RMS and peak-to-peak value of the panel respectively reach to 0.024mm and 0.108mm. Figure 11 displays the position of the actuator and corresponding error distribution of the surface after the second adjustment. Figure 12 displays the position of the actuator and corresponding error distribution of the surface after the third adjustment. This simulation process is repeated until the surface precision achieves the

Actuator position (a) and error distribution (b) of the sandwich panel after second adjustment

Actuator position (a) and error distribution (b) of the sandwich panel after third adjustment
required accuracy of the panel. Finally, the surface precision of the panel comes up to 0.011mm through four times adjustment. Ultimate actuator position and deviation distribution of the panel are shown in Figure 13.

Actuator position (a) and error distribution (b) of the sandwich panel after final adjustment
Through comprehensively analyzing the results of above simulation, eleven actuators are necessary to improve the surface precision of the sandwich panel with deviation caused by insufficient spring-back. The actuation

Substance of the back support structure
values are calculated by four-point-constrain least-squares method, as depicted in Table 3.
Actuator position and value obtained by FE simulation
Actuator | Actuator | Actuator | Actuator |
---|---|---|---|
NO. | value/mm | NO. | value/mm |
P0 | 0.116 | P6 | 0.109 |
P1 | −0.095 | P7 | 0.032 |
P2 | −0.149 | P8 | 0.054 |
P3 | −0.075 | P9 | −0.060 |
P4 | −0.164 | P10 | −0.085 |
P5 | 0.138 | – | – |
In order to verify the effectiveness of the shape control method proposed in this paper, a test platform based on multi-point adjustment is established. The platform mainly consists of back support structure and vacuum system, as shown in Figure 14. The actuator is movable along x-direction and y-direction, and the adjustment along z-direction is performed through screw driver, and the panel is bonded to the back structure by vacuum chuck.
The sandwich panel is mounted on the back structure by the way shown in Figure 15. Before that, these actuators required are installed on the back support structure according to the position coordinates obtained by simulation. Eleven actuators required are set according to the position coordinates shown in Figure 13a, and the corresponding actuation value listed in Table 3 is imposed on the panel one by one. According to the FE optimization process of shape control,five actuators (P0, P1, P2, P3, P4) are applied to the panel with the actuation value in Table 3 in the first. After the first adjustment, surface deviation of the panel is decreased from 62.7μm to 42.0μm, and the error distribution is shown in Figure 16(a). The whole surface deviation of the panel is redistributed after five actuators are added. As known from comparing Figure 16(a) and 10(b), the deformation trend of simulation and experiment is substantially unanimous. Then two actuators (P5, P6) are added to the panel again, and the surface accuracy reaches 29.5μm, as shown in Figure 16(b). The surface accuracy reaches 22μm after two more actuators (P7, P8), as shown in Figure 16(c). Finally, P9 and P10 actuators are applied to complete the fourth adjustment. Figure 16(d) displays the final error nephogram after shape adjustment test, with the RMS value 15.5μm and peak-to-peak value 69μm. Through shape control, surface accuracy of the sandwich panel increased by 75% (RMS). The results show that the method of shape control based on multi-point adjustment is effective to improve the surface precision of the sandwich panel. From the other hand, the results also show that the solution of the equivalent material parameters of honeycomb core is accurate. Comparing experiment results and simulation results of shape control, the consistency between experiments and simulations of the shape control is good. This result indicates that actuator position and adjustment value obtained by FE simulation can be used to guide the actual production. Number and position of the necessary actuators should be determined according to the accuracy requirements of the reflector panels.

Adjustment experiment of shape control

Error distribution of the test panel through shape control
4 Conclusion
The equivalent FE model of sandwich panels with honeycomb core is established based on sandwich panel theory. The honeycomb core is equivalent to a homogeneous orthotropic layer with uniform thickness. A mixed numerical-experimental method combining stiffness experiment and FE simulation with four-point support and center loading is designed to inversely solve the equivalent material parameters of the honeycomb. The optimal equivalent parameters of the honeycomb core are obtained by GA. The experiment and FE simulation under bearing load 100N, 200N, 300N and 400N are carried out to prove the reliability of equivalent parameters. The results show that the equivalent model of the sandwich panel is effective, and the solution of the equivalent material parameters of the honeycomb core is accurate.
On the basis of equivalent FE model, the FE analysis method of shape control is developed to optimize actuator position and adjustment volume. The shape control method and experiment platform based on multi-point adjustment is established to improve the surface precision of the sandwich panel. Through shape control, the sandwich panel with initial surface deviation 62.7μm (RMS) is decreased to 15.5μm (RMS). The results indicate that shape control based on multi-point adjustment is higher efficiency and better adaptability to improve shape precision for sandwich panels. On the other hand, the result also shows that the solution of the equivalent material parameters of honeycomb core is accurate.
Acknowledgement
The work was supported by the National Natural Science Foundation of china (grant nos. 51575028). The authors gratefully thank Hesheng CHANG and Changling HAO for their substantial and meaningful work.
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© 2019 D. Li et al, published by De Gruyter
This work is licensed under the Creative Commons Attribution 4.0 International License.
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- Crystallization of Nano-TiO2 Films based on Glass Fiber Fabric Substrate and Its Impact on Catalytic Performance
- Effect of Adding Rare Earth Elements Er and Gd on the Corrosion Residual Strength of Magnesium Alloy
- Closed-die Forging Technology and Numerical Simulation of Aluminum Alloy Connecting Rod
- Numerical Simulation and Experimental Research on Material Parameters Solution and Shape Control of Sandwich Panels with Aluminum Honeycomb
- Research and Analysis of the Effect of Heat Treatment on Damping Properties of Ductile Iron
- Effect of austenitising heat treatment on microstructure and properties of a nitrogen bearing martensitic stainless steel
- Special Issue on Fundamental Physics of Thermal Transports and Energy Conversions
- Numerical simulation of welding distortions in large structures with a simplified engineering approach
- Investigation on the effect of electrode tip on formation of metal droplets and temperature profile in a vibrating electrode electroslag remelting process
- Effect of North Wall Materials on the Thermal Environment in Chinese Solar Greenhouse (Part A: Experimental Researches)
- Three-dimensional optimal design of a cooled turbine considering the coolant-requirement change
- Theoretical analysis of particle size re-distribution due to Ostwald ripening in the fuel cell catalyst layer
- Effect of phase change materials on heat dissipation of a multiple heat source system
- Wetting properties and performance of modified composite collectors in a membrane-based wet electrostatic precipitator
- Implementation of the Semi Empirical Kinetic Soot Model Within Chemistry Tabulation Framework for Efficient Emissions Predictions in Diesel Engines
- Comparison and analyses of two thermal performance evaluation models for a public building
- A Novel Evaluation Method For Particle Deposition Measurement
- Effect of the two-phase hybrid mode of effervescent atomizer on the atomization characteristics
- Erratum
- Integrability analysis of the partial differential equation describing the classical bond-pricing model of mathematical finance
- Erratum to: Energy converting layers for thin-film flexible photovoltaic structures
Artikel in diesem Heft
- Regular Articles
- Non-equilibrium Phase Transitions in 2D Small-World Networks: Competing Dynamics
- Harmonic waves solution in dual-phase-lag magneto-thermoelasticity
- Multiplicative topological indices of honeycomb derived networks
- Zagreb Polynomials and redefined Zagreb indices of nanostar dendrimers
- Solar concentrators manufacture and automation
- Idea of multi cohesive areas - foundation, current status and perspective
- Derivation method of numerous dynamics in the Special Theory of Relativity
- An application of Nwogu’s Boussinesq model to analyze the head-on collision process between hydroelastic solitary waves
- Competing Risks Model with Partially Step-Stress Accelerate Life Tests in Analyses Lifetime Chen Data under Type-II Censoring Scheme
- Group velocity mismatch at ultrashort electromagnetic pulse propagation in nonlinear metamaterials
- Investigating the impact of dissolved natural gas on the flow characteristics of multicomponent fluid in pipelines
- Analysis of impact load on tubing and shock absorption during perforating
- Energy characteristics of a nonlinear layer at resonant frequencies of wave scattering and generation
- Ion charge separation with new generation of nuclear emulsion films
- On the influence of water on fragmentation of the amino acid L-threonine
- Formulation of heat conduction and thermal conductivity of metals
- Displacement Reliability Analysis of Submerged Multi-body Structure’s Floating Body for Connection Gaps
- Deposits of iron oxides in the human globus pallidus
- Integrability, exact solutions and nonlinear dynamics of a nonisospectral integral-differential system
- Bounds for partition dimension of M-wheels
- Visual Analysis of Cylindrically Polarized Light Beams’ Focal Characteristics by Path Integral
- Analysis of repulsive central universal force field on solar and galactic dynamics
- Solitary Wave Solution of Nonlinear PDEs Arising in Mathematical Physics
- Understanding quantum mechanics: a review and synthesis in precise language
- Plane Wave Reflection in a Compressible Half Space with Initial Stress
- Evaluation of the realism of a full-color reflection H2 analog hologram recorded on ultra-fine-grain silver-halide material
- Graph cutting and its application to biological data
- Time fractional modified KdV-type equations: Lie symmetries, exact solutions and conservation laws
- Exact solutions of equal-width equation and its conservation laws
- MHD and Slip Effect on Two-immiscible Third Grade Fluid on Thin Film Flow over a Vertical Moving Belt
- Vibration Analysis of a Three-Layered FGM Cylindrical Shell Including the Effect Of Ring Support
- Hybrid censoring samples in assessment the lifetime performance index of Chen distributed products
- Study on the law of coal resistivity variation in the process of gas adsorption/desorption
- Mapping of Lineament Structures from Aeromagnetic and Landsat Data Over Ankpa Area of Lower Benue Trough, Nigeria
- Beta Generalized Exponentiated Frechet Distribution with Applications
- INS/gravity gradient aided navigation based on gravitation field particle filter
- Electrodynamics in Euclidean Space Time Geometries
- Dynamics and Wear Analysis of Hydraulic Turbines in Solid-liquid Two-phase Flow
- On Numerical Solution Of The Time Fractional Advection-Diffusion Equation Involving Atangana-Baleanu-Caputo Derivative
- New Complex Solutions to the Nonlinear Electrical Transmission Line Model
- The effects of quantum spectrum of 4 + n-dimensional water around a DNA on pure water in four dimensional universe
- Quantum Phase Estimation Algorithm for Finding Polynomial Roots
- Vibration Equation of Fractional Order Describing Viscoelasticity and Viscous Inertia
- The Errors Recognition and Compensation for the Numerical Control Machine Tools Based on Laser Testing Technology
- Evaluation and Decision Making of Organization Quality Specific Immunity Based on MGDM-IPLAO Method
- Key Frame Extraction of Multi-Resolution Remote Sensing Images Under Quality Constraint
- Influences of Contact Force towards Dressing Contiguous Sense of Linen Clothing
- Modeling and optimization of urban rail transit scheduling with adaptive fruit fly optimization algorithm
- The pseudo-limit problem existing in electromagnetic radiation transmission and its mathematical physics principle analysis
- Chaos synchronization of fractional–order discrete–time systems with different dimensions using two scaling matrices
- Stress Characteristics and Overload Failure Analysis of Cemented Sand and Gravel Dam in Naheng Reservoir
- A Big Data Analysis Method Based on Modified Collaborative Filtering Recommendation Algorithms
- Semi-supervised Classification Based Mixed Sampling for Imbalanced Data
- The Influence of Trading Volume, Market Trend, and Monetary Policy on Characteristics of the Chinese Stock Exchange: An Econophysics Perspective
- Estimation of sand water content using GPR combined time-frequency analysis in the Ordos Basin, China
- Special Issue Applications of Nonlinear Dynamics
- Discrete approximate iterative method for fuzzy investment portfolio based on transaction cost threshold constraint
- Multi-objective performance optimization of ORC cycle based on improved ant colony algorithm
- Information retrieval algorithm of industrial cluster based on vector space
- Parametric model updating with frequency and MAC combined objective function of port crane structure based on operational modal analysis
- Evacuation simulation of different flow ratios in low-density state
- A pointer location algorithm for computer visionbased automatic reading recognition of pointer gauges
- A cloud computing separation model based on information flow
- Optimizing model and algorithm for railway freight loading problem
- Denoising data acquisition algorithm for array pixelated CdZnTe nuclear detector
- Radiation effects of nuclear physics rays on hepatoma cells
- Special issue: XXVth Symposium on Electromagnetic Phenomena in Nonlinear Circuits (EPNC2018)
- A study on numerical integration methods for rendering atmospheric scattering phenomenon
- Wave propagation time optimization for geodesic distances calculation using the Heat Method
- Analysis of electricity generation efficiency in photovoltaic building systems made of HIT-IBC cells for multi-family residential buildings
- A structural quality evaluation model for three-dimensional simulations
- WiFi Electromagnetic Field Modelling for Indoor Localization
- Modeling Human Pupil Dilation to Decouple the Pupillary Light Reflex
- Principal Component Analysis based on data characteristics for dimensionality reduction of ECG recordings in arrhythmia classification
- Blinking Extraction in Eye gaze System for Stereoscopy Movies
- Optimization of screen-space directional occlusion algorithms
- Heuristic based real-time hybrid rendering with the use of rasterization and ray tracing method
- Review of muscle modelling methods from the point of view of motion biomechanics with particular emphasis on the shoulder
- The use of segmented-shifted grain-oriented sheets in magnetic circuits of small AC motors
- High Temperature Permanent Magnet Synchronous Machine Analysis of Thermal Field
- Inverse approach for concentrated winding surface permanent magnet synchronous machines noiseless design
- An enameled wire with a semi-conductive layer: A solution for a better distibution of the voltage stresses in motor windings
- High temperature machines: topologies and preliminary design
- Aging monitoring of electrical machines using winding high frequency equivalent circuits
- Design of inorganic coils for high temperature electrical machines
- A New Concept for Deeper Integration of Converters and Drives in Electrical Machines: Simulation and Experimental Investigations
- Special Issue on Energetic Materials and Processes
- Investigations into the mechanisms of electrohydrodynamic instability in free surface electrospinning
- Effect of Pressure Distribution on the Energy Dissipation of Lap Joints under Equal Pre-tension Force
- Research on microstructure and forming mechanism of TiC/1Cr12Ni3Mo2V composite based on laser solid forming
- Crystallization of Nano-TiO2 Films based on Glass Fiber Fabric Substrate and Its Impact on Catalytic Performance
- Effect of Adding Rare Earth Elements Er and Gd on the Corrosion Residual Strength of Magnesium Alloy
- Closed-die Forging Technology and Numerical Simulation of Aluminum Alloy Connecting Rod
- Numerical Simulation and Experimental Research on Material Parameters Solution and Shape Control of Sandwich Panels with Aluminum Honeycomb
- Research and Analysis of the Effect of Heat Treatment on Damping Properties of Ductile Iron
- Effect of austenitising heat treatment on microstructure and properties of a nitrogen bearing martensitic stainless steel
- Special Issue on Fundamental Physics of Thermal Transports and Energy Conversions
- Numerical simulation of welding distortions in large structures with a simplified engineering approach
- Investigation on the effect of electrode tip on formation of metal droplets and temperature profile in a vibrating electrode electroslag remelting process
- Effect of North Wall Materials on the Thermal Environment in Chinese Solar Greenhouse (Part A: Experimental Researches)
- Three-dimensional optimal design of a cooled turbine considering the coolant-requirement change
- Theoretical analysis of particle size re-distribution due to Ostwald ripening in the fuel cell catalyst layer
- Effect of phase change materials on heat dissipation of a multiple heat source system
- Wetting properties and performance of modified composite collectors in a membrane-based wet electrostatic precipitator
- Implementation of the Semi Empirical Kinetic Soot Model Within Chemistry Tabulation Framework for Efficient Emissions Predictions in Diesel Engines
- Comparison and analyses of two thermal performance evaluation models for a public building
- A Novel Evaluation Method For Particle Deposition Measurement
- Effect of the two-phase hybrid mode of effervescent atomizer on the atomization characteristics
- Erratum
- Integrability analysis of the partial differential equation describing the classical bond-pricing model of mathematical finance
- Erratum to: Energy converting layers for thin-film flexible photovoltaic structures