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2014 Vol. 40, No. 11

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Volume 40 Issue112014
2014 Year 40 Volume 11 Issue E-journal
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Activity optimization in aircraft manufacturing cost control
Zhou Ning, Ma Jing, Luo Jide, Wang Canming
2014, 40(11): 1481-1486. doi: 10.13700/j.bh.1001-5965.2013.0723
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Activity-based cost (ABC) was used to replace conventional volume-based product-costing system in addressing cost calculation and optimization issues in the aircraft manufacturing industry. Activity-based management (ABM) was applied to further implement cost control and optimization based on the activity analysis results. Cost calculation based on ABC in five types of subcontract products from a China-based aviation manufacturing enterprise (XYZ) resulted in an optimized workflow. The optimization was realized via adopting measures including a reduced or eliminated activity, activity selection or sharing. Results show that ABC is more accurate than the conventional volume-based product-costing system, and ABM can be a more effective optimization tool for cost reduction and cost control.
Incremental algorithm of multiple linear regression model
Wang Huiwen, Wei Yuan, Huang Lele
2014, 40(11): 1487-1491. doi: 10.13700/j.bh.1001-5965.2013.0680
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With the development of computer-related technology, people can continuously obtain data faster and faster. Facing with the massive and continuously updated data sets, incremental algorithm was introduced to the popular multiple linear regression analysis. The incremental algorithm of least squares estimation model was derived based on incremental expression of cross product matrix. And further this algorithm was extended to other estimation models and test statistics. The incremental algorithm uses the information of all dataset, which can get the same results with non-incremental methods. This algorithm can save the time in reading and writing data, release the impression on transportation, and thus speed up the computation. Simulation results show that, this algorithm can improve computational efficiency and is very useful in many conditions.
Static force equalization for dissimilar redundant actuator system
Fu Yongling, Fan Dianliang, Li Zhufeng
2014, 40(11): 1492-1499. doi: 10.13700/j.bh.1001-5965.2013.0699
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The dissimilar redundant actuator system (DRAS) which consists of power-by-wire actuators, EHA (electro-hydrostatic actuator) and EMA (electro-mechanical actuator), addresses the problem of the distribution of central hydraulic source and pipelines. It also resolves the common fault, which indicates the trend of more-electric-aircraft. To start with, the construction as well as the working principle of the DRAS was described. Considering the air load of control surface and connection stiffness, the closed-loop system model within active/active working mode was built up. Further, the mechanism of static force fighting was introduced. The idea which uses the method of adjusting the electrical parameters so as to compensate the static force fighting was proposed, and based on the above principle three kinds of static force equalization for eliminating static force fighting were put forward, and then theoretical and simulation analysis were discussed. Finally, a comprehensive comparative analysis on the elimination of static force fighting, isolation and other aspects was exhibited for the three control strategies. The results provide theoretical directions for DRAS design and static force fighting solutions.
Finite element analysis of electromigration induced stress in through-silicon-via
Su Fei, Lu Zixing, Liu Ping, Wang Yuan
2014, 40(11): 1500-1506. doi: 10.13700/j.bh.1001-5965.2013.0646
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Through-silicon-via (TSV) plays a key role in chip's vertical interconnection in 3D electronic package, so its reliability shows great importance. As the current density through TSV increasing, current induced stress has larger and larger influence on the TSV's reliability. The methodology for evaluation of electromigration induced stress in TSV was developed based on the coupling equation of stress-mass diffusion and the principle of finite element method (FEM), together with the user defined element on the platform of ABAQUS. The numerical simulation of this model was set and its accuracy was verified with analytical solution. The electromigration problem was simulated with a finite element model; The evolution and distribution of electromigration induced stress, strain and vacancy concentration in copper pour hatch were described. So the reliability of 3D electronic package could be assessed someway.
Simulation of universal CCSDS Turbo-codes decoder of non-standard parameters
Zhao Qi, Du Yujiao
2014, 40(11): 1507-1511. doi: 10.13700/j.bh.1001-5965.2013.0732
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A universal Turbo-codes decoder was designed, which not only covers the parameters suggested by consultative committee for space data systems (CCSDS), but also supports other frame length (an integral multiple of 255bit) within 16384bit. Standard and non-standard frame lengths, as comparisons, were both simulated on three decoding algorithms, including MAP, SW-MAP and log-MAP. The algorithms were realized in the form of C++ dynamic link library. Python test program was written to generate random signal of needed length and call the DLL mentioned above for encoding and decoding. The graphs about the relation between signal noise ratio and bit error rate were drawn after data calculation. By simulation, the decoder designed was proved universal. In addition, performance of different algorithms were compared and analyzed. Simulations were done to study the relations between decoding performance and some key parameters, including frame length, bit rate, the number of iterations and so on.
Space debris environment modeling in low earth orbit based on resident time ratio
Shen Jingsong, Liu Ye, Hu Songjie, Han Chao
2014, 40(11): 1512-1517. doi: 10.13700/j.bh.1001-5965.2013.0716
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For the distribution analysis of space debris in the low earth orbit, a new statistical modeling method for space debris was proposed based on the debris resident time in the space grid. Polynomial fitting and extraction techniques for debris resident time statistic were introduced to obtain the basic modeling datum. Then, the distribution and evolution regularity of debris in low earth orbit was studied by virtue of the polynomial prediction, polynomial interpretation, time serials analyses and so on according to the modeling datum storage. Finally, a modeling case utilizing the two line elements (TLEs) was given. The modeling results were validated by the ORDEM2000 model. Some subtle distribution regularities were deduced. The modeling method and analysis results are helpful for researches on orbit designing, collision risk evaluation and collision defense for spacecraft long-term flying in the low earth orbit.
Application of small sample theory in aero engine development costs estimation
Liu Fang, Zhang Haitao
2014, 40(11): 1518-1525. doi: 10.13700/j.bh.1001-5965.2014.0340
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The usability of the partial least squares method of small sample theory in military aero engine development costs estimating was discussed. The technical and development expense data of more than ten kinds of military turbojet and turbofan engine were collected. The technical parameters such as turbine inlet temperature, military fuel consumption rate, military thrust, afterburner thrust, thrust weight ratio, engine weight, total pressure ratio, air flow, overhaul life, number of prototypes and completion time were selected. The partial least squares method in military aero engine development costs estimating was used. The military aero engine development cost estimation model based on the major technical parameters was formed, and the development concept inheritance coefficient of military aero engine was established. The results show that the model's accuracy is improved compared with the other existing models, reaching 10%, and can be used to support for aero engine development cost estimation quickly.
Winding distribution characteristic of slot-less tubular permanent magnet linear actuator and its experiment
Huang Xuzhen, Li Liyi
2014, 40(11): 1526-1530. doi: 10.13700/j.bh.1001-5965.2013.0704
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The slot-less tubular permanent magnet linear motor was selected as a linear actuator using for the attitude control of aircraft. The winding distribution factor of the annular slot-less winding was researched. The model of the winding factor distributing along the axis that considered the influence of the phase-to-phase insulation was established. The winding distribution characteristics of the single-polar and bipolar windings were compared. The influence of the phase-to-phase insulation on the winding distributions for these two windings was expounded. A slot-less tubular linear actuator prototype was manufactured. The tested and calculated no-load electromotive force (EMF) waves were consistent, which verified the validity of the theoretical study. And the thrust and dynamic response characteristics were tested. The results reflect that the linear actuator is with the advantages of small armature reaction and quick dynamic response speed.
150kV/30kW inverter for electron beam welding power supply design
Zhang Wei, Du Huicong, Qi Bojin, Xu Haiying
2014, 40(11): 1531-1536. doi: 10.13700/j.bh.1001-5965.2013.0715
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With the consideration of characteristics of high voltage and high power output of 150kV/30kW power supply of electron beam welding (EBW), low-voltage circuit was designed to be composed of insulated gate bipolar transistor (IGBT) isolated DC power supply and full bridge inverter in series, and high-voltage circuit was paralleled by three groups of high-voltage transformer with 10 times voltage doubling rectifier circuit in series. At the same time, high voltage sampling circuit, electron beam current sampling circuit, and dual closed-loop control circuit were proposed. Based on the above technologies, the 150kV/30kW electron beam welding power supply was successfully developed. Experimental results show that the linearity of output voltage and output beam current of high-voltage accelerating power supply is excellent, the stability of output voltage and output beam current of high-voltage accelerating power supply is about 0.5%, which could satisfy the EBW requirements.
Press bending equivalent simulation model of integrally reinforced panel
Li Weidong, Wan Min
2014, 40(11): 1537-1542. doi: 10.13700/j.bh.1001-5965.2013.0726
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The elastic and plastic deformation distribution of skin and stiffener were analyzed during press bending for integrally reinforced panel with inside ribs. According to the characteristics of plastic deformation on inside stiffener and mainly elastic deformation on skin, a geometrical equivalent method was proposed which simplified the skin component to stiffener with virtual material properties. The calculative formula of equivalent coefficient was educed based on inertia moment. For complicated integrally reinforced panel, the establishment process and calculative method of equivalent model were also introduced. The finite element analysis and experiment of Ⅰ -style single stiffener and gridding stiffener panels were carried out. The comparisons on efficient and precision between detailed model and equivalent model were made and verified by experimental data. The equivalent model for press bending was proved to be reliable and highly efficient which can be used for simulation and parameter optimization of large complicated gridding integrally reinforced panel.
Sensor placement of flywheel under diagnostic criteria and cost estimation
Liu Rui, Zhou Jun, Li Xin, Liu Yingying
2014, 40(11): 1543-1548. doi: 10.13700/j.bh.1001-5965.2013.0676
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The sensor placement method of flywheel and cost estimation criteria were proposed. The relationship between the function modular and the fault types of the flywheel system was analyzed in order to build the qualitative fault transmit model. The transmit model of the flywheel based on directed graph (DG) was presented. Firstly, control circle in the DG was operated. After that, roots satisfied the detectability and isolability criteria were generated in order to set up the bipartite graph. Then, greedy algorithm was used to resolve the key sensor selecting problem. Finally, considering the volume, the weight, the power consumption, and the processing capacity, resource occupation degree (ROD) was proposed to describe the cost. The ROD easily expresses the importance of certain resources, can avoid the weakness of certain resources, and also is easy to expand. The final sensor placement result was estimated by the ROD.
Impact of antenna beam granularity on sliding spotlight spaceborne SAR image quality
Zeng Hongcheng, Chen Jie, Yang Wei, Zhang Haojie
2014, 40(11): 1549-1554. doi: 10.13700/j.bh.1001-5965.2013.0669
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Antenna beam in sliding spotlight spaceborne synthetic aperture radar (SAR) cannot continuously scan the illuminated scene, leading to paired-echo in SAR images. A method quantitatively analyzing the impact of antenna beam granularity was presented. Firstly, mathematical mode of sliding spotlight spaceborne SAR was proposed based on the azimuth antenna beam granularity. Then, the qualitative and quantitative studies about the impacts of antenna beam granularity on image quality were proposed. And the expression for determining both amplitudes and positions of paired-echo and the minimum beam granularity was illuminated. Moreover, the impacts of paired-echo on azimuth resolution, integrated side lobe ratio (ISLR), peak side lobe ratio (PSLR) and system gain were discussed, at different operation frequencies, e.g. X-band and C-band. Therefore, the analysis provides a theoretical basis for minimum antenna beam granularity design. Finally, computer simulations testify to the validity of theoretical analysis.
Long-term open-hole compression strength prediction of composite laminates
Kang Jun, Guan Zhidong, Li Zengshan, Li Xing
2014, 40(11): 1555-1562. doi: 10.13700/j.bh.1001-5965.2013.0681
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Accelerated testing methodology (ATM) predicts long-term strength in low temperature with short-term in high temperature, which is based on the viscoelasticity of matrix and the time-temperature superposition principle (TTSP). The strain invariant failure theory (SIFT) was modified by using micro maximum strain criteria to judge fiber tensile and compressive failure. Master curve of storage modulus of epoxy resin and the time-temperature shift factors were tested from dynamic mechanical analysis(DMA). Master curves of SIFT critical parameters were constructed by tension and compression test for unidirectional carbon fiber reinforced plastics (CFRP) under various temperatures with the time-temperature shift factors of matrix resin. Long-term compression strength of open-hole composite laminates was predicted based on SIFT/ATM combined method. The damage process of fiber and matrix was simulated by progressive damage analysis as well. Good agreement between numerical results and experiments was observed, which demonstrates the applicability of this method.
Kinematics and performance analysis of rudder blade fixed hydraulic spherical joint
Fang Shoulong, Wang Liang, Ding Shuai
2014, 40(11): 1563-1567. doi: 10.13700/j.bh.1001-5965.2013.0727
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In view of the problem of driving method for the spherical motion mechanism, a new type of hydraulic drive spherical joint with two degrees of freedom was proposed. The joint mechanism used a full cycle rotating motor and a rudder blade swing motor as drive, adopted a measuring system of slide support frame, and could achieve a full rotation. The oil circuit design programs for the two driving motor were given respectivly. The reasonable sealing method was adopted in different parts of the mechanism. Based on the mechanism theory, the forward and inverse kinematics equations and the velocity Jacobian matrix were derived and the singular configuration of the mechanism was found. Through the analysis of dexterity performance index of the mechanism, the workspace was found by simulation when the mechanism was in a good performance. The spherical joint mechanism has the following characteristics, compact structure, high motion accuracy, large load, and it can complete the omni-directional output.
Attitude control for hypersonic vehicle based on SMDO-TLC
Shao Xingling, Wang Honglun
2014, 40(11): 1568-1575. doi: 10.13700/j.bh.1001-5965.2013.0731
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In consideration of actuator input constraints, a novel attitude control method driven by sliding-mode disturbance observer was presented for supersonic vehicle which is fast time-varying, strong coupling combining with parameter non-deterministic. Firstly, via introducing the concept of second-order linear differentiator (SOLD), it was indicated that peaking phenomenon caused by a combination of first-order lag and pseudo differentiator, which is similar with SOLD, would emerge during the transient profile of differentiation of the nominal command in the existing trajectory linearization control (TLC). Nonlinear tracking differentiator (TD) was used to produce the nominal command and its derivative, saturation of actuator during transition time was solved. Secondly, second order sliding-mode disturbance observer (SOSMDO) based on integration of sign function was designed to reconstruct compound disturbances in the loops of attitude and angular rate respectively, and then compensation control law was proposed to realize attitude control. Simulation results show that the technique proposed can overcome the impact of large-scale perturbations of interference and aerodynamics parameters, meanwhile good dynamic character and steady quality was achieved, the hypersonic vehicle control demand of fast time-varying, high precision and strong robustness can be satisfied.
Analysis for centered nonoscillatory scheme of third order
Li Yansu, Yan Chao, Qu Feng, Yu Jian
2014, 40(11): 1576-1580. doi: 10.13700/j.bh.1001-5965.2013.0734
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Choosing symmetric stencils, a centered nonoscillatory scheme of third order scheme (Cn3) constructs a formula which achieves third-order accuracy. A modification of the original estimates, in the reconstruction procedure, was undertaken by employing a monotonicity region as well as an accuracy one. After the very modification, the Cn3 scheme not only obtained nonoscillatory results near discontinuities but also achieved high-accuracy calculation in smooth regions. By using several typical one- and two-dimensional test cases, Cn3 scheme was compared with the weighted essentially non-oscillatory (WENO) schemes of third and fifth order. The properties of capturing discontinuities, stability/robustness and numerical dissipation were significantly considered. The results of the numerical experiments confirm that Cn3 scheme has the ability to suppress spurious numerical oscillations near shocks and contact discontinuities when sharply capturing them, which indicates its characteristics of stability and accuracy, and has low dissipation in smooth region at the same time. Cn3 scheme is worth of further study and application.
On-orbit real-time health assessment of satellite attitude control system
Song Fei, Qin Shiyin
2014, 40(11): 1581-1588. doi: 10.13700/j.bh.1001-5965.2014.0057
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According to technique requirements of on-orbit autonomous intelligent management and control for spacecrafts, especially for satellite systems, an on-orbit real-time health assessment method for satellite attitude control systems was proposed based on a multi-level fuzzy comprehensive evaluation framework. In view of performance characteristics and actual capabilities, a satellite attitude control system was divided into three parts of attitude measurement, actuating mechanism and attitude control. In this way, its health level may be determined by health status of three parts so that the fuzzy evaluation for every part was carried out at first and then the integrative health performance was given through synthetically weighted integration with the ones of three parts. Therefore a synthetic integration strategy with variable weights for different health conditions of various parts was employed to complete the comprehensive evaluation of satellite attitude control systems according to variable weight synthesizing principle, in which the variable weights depended on the membership degree of health level of various parts. Simulation experiment results demonstrate that the proposed health assessment method can achieve on-orbit real-time health assessment of satellite attitude control system effectively and efficiently.
Gross error detection and correction method of public reference point in aircraft assembly coordinate system
Chen Lei, Huang Xiang, Zhao Lele, Li Shuanggao
2014, 40(11): 1589-1594. doi: 10.13700/j.bh.1001-5965.2013.0672
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A gross error detection and correction method of the public reference point in an aircraft assembly coordinate system was proposed for such deviations of a public reference point in a digitalized aircraft assembly system as resulted from foundation sinking of a workshop or other factors. In this method, a coordinates transformation linear model applicable to a large rotation angle was built by expanding the Bursa-Wolf coordinates transformation model in Taylor' s expansion, and in combination with the method of quasi-accurate detection (QUAD), the reference point with a relatively large deviation was detected and estimated, and further a coordinates correction model of the public reference point was put forward in a global coordinates for assembly. The public reference point was measured with a laser tracker and then the public reference point coordinates was corrected by the abovementioned method. Experiments prove that the gross error could be effectively detected and corrected by this method, thus the precision of the aircraft assembly coordinate system could be improved.
Dynamic surface control for hypersonic vehicle based on invariant manifold
Hou Delong, Chen Bin, Wang Qing, Dong Chaoyang
2014, 40(11): 1595-1601. doi: 10.13700/j.bh.1001-5965.2013.0673
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An adaptive dynamic surface control scheme based on invariant manifold was proposed for the longitudinal motion control problem of hypersonic vehicle. With reasonable hypothesis, the longitudinal dynamic model was separated into flight-path angle loop and velocity loop. Flight-path angle loop was formatted into parametric-strict-feedback form. The unknown parameters of the system were estimated based on the method of invariant manifold. The proposed dynamic surface control scheme can guarantee the global uniform stable of the error of estimation and the global boundedness of the closed system. The decoupled relationship between estimator and controller made the parameter tuning more easily than the traditional adaptive dynamic surface method. Simulation results validate the prominent improvement in parameters estimation and the good performance of the closed system.
Construction of invariants of Gaussian-Hermite moments
Zhang Chaoxin, Xi Ping, Hu Bifu
2014, 40(11): 1602-1608. doi: 10.13700/j.bh.1001-5965.2013.0677
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Moments and functions of moment are widely used in image processing and pattern recognition due to their strong ability to represent features of an image. However, the researches on Gaussian-Hermite moments with which own orthogonal properties are still relatively less currently. Gaussian-Hermite moments were deeply studied, and correspondently, Polar-Gaussian-Hermite moments were proposed in polar coordinate. The method to compute the functions of both moments using raising and lowering operators were presented. Finally, the rotation invariants of Gaussian-Hermite moments were derived based on the Polar-Gaussian-Hermite moments and an independent and complete set of the invariants were given. The given experiment validates the correctness and good digital stability of the proposed invariants.
New method for single-snapshot two-dimensional direction of arrival estimation based on noncircular signals
Li Lei, Li Guolin, Ma Yunpeng
2014, 40(11): 1609-1614. doi: 10.13700/j.bh.1001-5965.2013.0770
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To resolve the problem of fast estimating two-dimensional direction of arrival (DOA) in coherent signals environment with two parallel linear arrays, a new method for single-snapshot two-dimensional DOA estimation was presented based on noncircular signals. New coordinate system was established and array received data was changed to its conjugate data. Pseudo snapshot data was made and array aperture was doubled by reconnecting data. The coherence between the signals was solved and two-dimensional DOA can be estimated only by using singular values decomposition (SVD) for extended matrix which was made of three pseudo snapshot matrix. The method has low complex degree and high estimation accuracy, so it is suitable for DOA estimation of high real-time attribution background. Simulation indicates that the method is effective.
4-DOF longitudinal dynamic simulation of powered-parafoil
Yang Hua, Song Lei, Wang Wenjian, Huang Jun
2014, 40(11): 1615-1622. doi: 10.13700/j.bh.1001-5965.2014.0086
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With the consideration of relative motion between payload and canopy, longitudinal dynamic of parafoil was simulated. Canopy and suspension line were regarded as a 3-DOF rigid body. Adding another degree of freedom of swing payload, a 4-DOF longitudinal dynamic model was proposed. Dynamic response was solved after step increasing of throttle which led to increasing of climbing angle. The main reason of canopy collapse that happens just after throttle up is the rapid changes of angle of attack which can be over the stall angle. Control envelope was calculated that is composed of throttle value and corresponding growing rate of throttle. Little change of power up has no limit on increasing rate, but large change does, and the limit increases with the increasing throttle value. In addition, mechanical energy change of payload before and after landing was calculated. Rapid power up control was proposed as a new flare landing method for powered-parafoil. The results of mechanical energy analysis method show that this new flare control can decrease mechanical energy at the moment of landing that means weaker shock to front power system.
Hazard analysis technique based on hazard factors
Zhao Yuan, Jiao Jian, Zhao Tingdi
2014, 40(11): 1623-1628. doi: 10.13700/j.bh.1001-5965.2014.0124
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Considering the lack of concrete hazard analysis tool for implementing hazard analysis during the preliminary design stage, a hazard analysis technique based on hazard factors was proposed. In this hazard analysis technique, hazard elements were identified, components of a system were classified, and the states of different component types were analyzed, based which potential hazards can be identified by analyzing the effect of various coupling relationships between these states to the hazard elements. A case study about the fuel system on airplane was presented which demonstrates the engineering practicability and effectiveness of the technique in preliminary hazard analysis. The hazard analysis technique can effectively identify potential hazards at the preliminary design stage, provide a basis for the subsequent design and system safety, and can also be used for safety analysis of follow-up development phase.
Vibration-controlling mechanism and controlling effectiveness of plate with piezoelectric network
Yi Kaijun, Li Lin
2014, 40(11): 1629-1636. doi: 10.13700/j.bh.1001-5965.2013.0641
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The given electromechanical coupled kinetic equations of the plate with piezoelectric network were solved by decomposing the responses into linear combination of sub-modal piezoelectric systems' responses. Through the research of the response behaviors of sub-modal piezoelectric systems when the coupled system was stimulated by a pulse, it is found that there are two different ways for the coupled system to dominate their vibration. The optimal electrical parameters of sub-modal piezoelectric systems were found through the analysis of transfer functions. Based on that, one of the sub-modal piezoelectric systems was set optimally; In this condition, the response behaviors of all sub-modal piezoelectric systems and the multiple-mode controlling effectiveness of the system were studied. The results show that the plate with piezoelectric network has the capacity to suppress multimode vibration; Particularly, when one modal requires higher control effect, this system with parallel resistor and inductor can satisfy the aforementioned request.
Solution of stress intensity factor of surface cracked geometry with clamped ends
Cao Shusen, He Xiaofan, Yang Boxiao, Liu Wenting
2014, 40(11): 1637-1642. doi: 10.13700/j.bh.1001-5965.2013.0717
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Determination of the stress intensity factor (SIF) of surface cracked geometry with clamped ends is necessary for crack growth analysis in laboratory. Based on the feature of the clamped ends, the clamped condition was simplified as a combined uniform tension stress and bending moment act with the rotation angles of the specimen ends retained to be zero. The elastic potential energy of the equivalent model was derived based on Newman-Raju expression of SIF for surface crack under free uniform tension and bending moment, and then the function relationship between the uniform tension stress and the bending moment was deduced using Castigliano's first theorem. By superposition, the SIF expression of the equivalent model was given. To verify the validity of the expression, SIF solutions of some representative surface cracked geometry with clamped ends were obtained by Abaqus. Comparisons indicate that the expression is accurate enough. In addition, the relationship of crack shape and length-to-thickness ratio to the modifying factor for clamped ends was analyzed.

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