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Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper emphasis that to evaluate the complex risk about super-huge type project, we should not only think about the probability and valuable influence of risk, but also put in factors of the main body 's value preference and dynamic game playing. Thus method makes the evaluation has more rational behavioral base. Firstly, this paper analyses the characteristic of the risk evaluation and game-playing feature in the process of risk development. Secondly, it builds evaluation index system and the dynamic and blurry evaluation model for the risks. Thirdly, it tests and amends the important parameters using testing methods of behavior economics. Lastly, it uses this model to counts four main kind of risks index for a representative project. It can provide a useful and simple tool for complex risk evaluation and public communication of the super-huge type project. [ABSTRACT FROM AUTHOR]

Copyright of China Textile Leader is the property of China Textile Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Super-organization is a new mode of development which provides the enterprises with new ideas to use external resources to the greatest extent so as to gain competitive edge in the background of globalization. Knowledge conversion among organizations can promote the formation of super-organizations. This paper is intended to analyze the process of the formation of super-organizations through employing Game Theory. It is found that the main driving factor for the super-organizational formation is from knowledge conversion, which is caused by the differences in the storage of knowledge possessed by different organizations and the ensuing comparative advantages acquired by these organizations. In the light of this observation, this paper tries to discuss the super-organizational formation mechanism with game theory and from the perspective of knowledge conversion, and to explore the strategies that the organizations may take in the process of maximizing their profits. [ABSTRACT FROM AUTHOR]

A Prototypical Serpentine Belt Drive System (PSBDS), which includes driving pulley, driven pulleys, one tensioner and belt, is taken as a research example for calculating transverse vibration of a belt in serpentine belt drive systems. A model for estimating the transverse vibration of the belt in a PSBDS is proposed. In the model, the belt is simplified as a moving Bernoulli-Euler beam, and the pulley and the tensioner arm is regarded as rotational rigid body. The transverse vibration of belts in PSBDS in steady state is obtained using Boundary Value Problem solving technology. The transverse displacements of belts are continuous function with time and belt location variables. To use conventional methods for solving discrete system e-quations, the vibration equations of belts are discreted using Garlerkin method. An experiment is carried out for getting the vibration of belts and pulleys, and the test results are compared with calculations. It is shown that the experiment and calculation data for belt transverse vibrations and rotational response of pulleys agrees well, which validate the calculation methods proposed in this paper. The method presented in this paper is useful for designing complex serpentine belt drive system, such as engine front end accessory drive systems. [ABSTRACT FROM AUTHOR]

The influence of valve setting's pretension force on the pressure difference caused by deflected disc at the valve opening point is studied in this paper. Taking piston valve setting for instance, based on finite element simulation and theoretical calculation, the mathematical relationship between pretension force and the pressure difference caused by deflected disc at the valve-opening point is found. Based on the mathematical model, the influence of piston valve body's elastic modulus and deflected disc's elastic modulus are analyzed. Finally the paper shows that the smaller the elastic modulus of piston valve body, the greater influence the pretension force has on the pressure difference, and the influence of the change of the elastic modulus of deflected disc on pretension force's function is very small. [ABSTRACT FROM AUTHOR]

In this paper, aiming at the practical whole aero-engine vibration, a new rotor-ball bearing-stator coupling system dynamic model is established. The main characteristics of the new model are as follows: 1) the coupling effect between rotor, ball bearing and stator is considered fully; 2) the flexible support and the squeeze film damper (SFD) are considered; 3) the rotor is considered as Equisection Euler Free Beam model, and its vibration is analyzed through cutting limited modes; 4) nonlinear factors of ball bearing are modeled, such as the clearance of bearing, nonlinear Hertzian contract force, and the varying compliance; 5) rubbing fault between rotor and stator is considered. In this paper, the numerical integral method is employed to obtain system' s responses, and the whole aero-engine vibration characteristics are studied. [ABSTRACT FROM AUTHOR]

Serpentine belt with multi-ribbed driven system are widely used in the automotive industry to drive engine front end accessories, such as the alternator, air conditioner, power steering pump, and so on. An important component in a serpentine belt driven system is a tensioner that can automatically compensate for tension changes in the belt. In this paper, a serpentine belt system model incorporating bending stiffness of the belt is established using Hamilton equation. The influences of design variables of a tensioner on the equilibrium deflections are investigated using the model. An optimization method to reduce the maximum transverse deflections of the belt span and increase the tensioner effectiveness is presented. The calculated results show that with the optimized tensioner, the maximum transverse deflection of the system is suppressed effectively, and the coupling between the pulley vibration and the span vibration is also reduced. The dynamic modeling method for the serpentine belt driven systems and the belt transverse vibration control method presented in this paper can be used for the optimization design of the belt driven system. And also it is useful to estimate the design parameters of a tensioner. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposed a zero-sum magnetic field integral technology to minimize the crosstalk effect in straight light path optical current transducer. The discrete Ampere's law was proposed and studied based on analyzing of the magnetic field integral along a discrete loop, and its mathematical model was established. The Sm model of regular polygonal discrete loop and the mSm model of Sm regular distribution were discussed. The results showed that the Sm model possessed 2m zero-sum points, and the currents which placed on the zero-sum points did not contribute to the magnetic field integral result of Sm model. The origin point interchanged with the zero-sum point when any two Sm models of the mSm model switched places. Based on that conclusion, the zero-sum theorem of Sm model and the reciprocal theorem of mSm model were proposed. The discrete Ampere's law, the zero-sum theorem of Sm model and the reciprocal theorem of mSm model together made up the theory system of magnetic field integral along regular polygonal discrete loop, which still met the Ampere's law. [ABSTRACT FROM AUTHOR]

Singace fold model and Johnson Cook constitutive equation are used to study energy conversion process of interactions between impact objects and metal shell, in which material strengthening effect of the strain and strain rate and temperature effect caused by impact load are considered. Angle increment fold method is put forward to calculate plastic deformation energy. According to system energy conservation composed of impact object and metal shell, analytical expressions of speed-displacement of impact object and instantaneous load between impact object and metal shell and temperature distribution function caused by plastic deformation of metal shell are gained. Based on comparison between analysis of plastic deformation process under impact load with metal shell of different materials and finite element calculation result, validity of the calculation method is proved in this paper. [ABSTRACT FROM AUTHOR]

Effects of the rigid rotation on the eigen-frequency, modal and dynamical response of a two degrees-of-freedom mass-spring vibration system are clarified in the paper and the results provide important guidance for dynamic coupled analysis on centrifugal vibration of general elastic structures. There are two dynamic frequencies for the centrifugal vibration system in which the first order one decreases whereas the second order one increases linearly with the rigid rotation. Dynamical response of the mass is expressed by the mass trajectory evolution which is associated with initial conditions of the vibration, rigid rotation speed, initial eccentric position and vibration stiffness. The mass trajectory is composed of the non-eccentric vibration and the eccentric one, in which the former is dependent on initial conditions of the vibration, rigid rotation speed and vibration stiffness and the latter is determined by the initial centrifugal position, rigid rotation speed and vibration stiffness but has nothing to do with initial conditions of the vibration. Based on the analysis of dynamic frequencies and responses of the system, the maximum and critical rigid rotation speeds are proposed for the centrifugal vibration system with two degrees of freedom. [ABSTRACT FROM AUTHOR]

A finite element model was developed for solving horizontal seismic response of aqueduct with fluid--structure coupling and pile--soil--structure interaction in this paper. Equivalent linearization principle was employed to deal with the nonlinear characteristics of the soil. Based on the analysis results of free filed, the parameters of viscous-elastic artificial boundary and the input method of earthquake wave were given. Analysis was carried out by using this finite element model, the results were in good agreement with the pseudo-dynamic testing data. At the same time, the results of the pseudo dynamic test and finite element calculation show that water has a certain effect on the earthquake response of the aqueduct structure. On the water condition, the fundamental frequency of the aqueduct structure decreases and deviates from the energy basic frequency of the input seismic wave farther than that on the water-less condition. In this case, it has certain damping effect. [ABSTRACT FROM AUTHOR]

Among structural health monitoring (SHM) techniques, Lamb waves are frequently used as diagnostic tools to detect damage in plate-like structures. Temperature variation can cause significant changes in guided-wave propagation and transduction for SHM. It is most important to compensate the temperature variation for those methods in which the present signals should be compared with the baseline ones in order to detect the structure damage. In this paper, a transient dynamic finite element simulation of Lamb wave for damage detection in a stiffened plate under different temperature conditions is carried out on the commercial finite element code ANSYS platform. Simulations are conducted over a temperature range of 25~75 °C using 275 kHz as excitation frequencies. The changes in temperature-dependent material properties are used to measure the differences in the waveform of the response signal. Then controlled experiments examine changes in Lamb wave propagation and transduction using PZT-5A piezoelectric wafers under quasi-statically varying temperature (from 5 °C to 60 °C). The baseline selection method and baseline signal stretch method are used to compensate the temperature influence on Lamb wave propagation. The results of the numerical simulation and experiments demonstrate the effectiveness of the temperature compensation approach. The requirement of maximum temperature interval for baseline signal set is obtained, thus the simulated damage on the aluminum plate can be detected effectively under varying temperature environment. [ABSTRACT FROM AUTHOR]

An adaptive substructure testing method with unscented Kalman filter on the basis of traditional substructure pseudo--dynamic testing method is proposed in order to deal with the negative influence from the inaccuracy of the restore force model of numerical substructure. An online identification technique is adopted to estimate hysteretic model parameters of the testing substructure and modify the model parameters of the numerical substructures in the substructure testing. Fast and accurate hysteretic model identification is the key issue of adaptive substructure testing. In this paper, the parameters of hysteretic model of experimental substructure are taken as a part of the state vectors of experimental substructure and identified online with unscented Kalman filter. The performances of the proposed method are verified through numerical simulation. Results show that the new method has good accuracy and high computation efficiency, and test results are significantly improved over conventional substructure method with unchanged mathematical model of numerical substructure. [ABSTRACT FROM AUTHOR]

A new multi-physical coupled dynamic model of high-speed motorized spindles is established in the paper. The entire model consists of four sub--models: bearing, thermal, spindle dynamic and electromagnetic models. Based on the coupled relationships, five coupled factors, which are thermal expansion, centrifugal expansion of bearing inner ring, contact expansion of bearing ring, the unbalanced magnetic pull and centrifugal force, have been presented. And effects of the coupled factors on the operation states of motorized spindles could be acquired from the designed calculation procedures. Finally, an overall experiments and calculations on a 2ZDG60 motorized spindle are carried out under several operating conditions. Calculation results show that the coupled factors have great influence on dynamic stiffness and loss power of the bearings, dynamic behavior of the spindle, respectively. The good agreement between the theoretical results and the experimental data indicates that the multi-physical coupled dynamic model is capable of accurately predicting the dynamic behavior and temperature rise distribution of high speed motorized spindles. [ABSTRACT FROM AUTHOR]

A novel method of mass segmentation in mammogram is proposed in this paper. First, a mathematical model is presented based on the clinical features of the mass and a multi-filtering method is used to detect the mass' location. Then, according to the result of clustered pixels, which is got by mean shift algorithm, rough handling masses could be obtained. Finally, the active contour without edge model is applied to refine the rough-wrought masses. Experiments implemented on the public MIAS database indicate that the proposed method can achieve better true positive rate than the morphological component analysis method with low false positive rate. In addition, the proposed segmentation method could emerge complete boundary, which could meet the clinical examination and diagnosis demand. [ABSTRACT FROM AUTHOR]

Between two contact surfaces of bolt connection, there exist the friction, slip and slap for the interracial gaps. So the dynamical behavior of the bolted built-up structure usually shows the nonlinear characteristics. Estimating the non-linear dynamical characteristic parameters of bolt joint is very important to create the complex dynamics model considered the joint characteristics. In the paper, the bolted beam structure is taken as an example and the method for identifying nonlinear characteristic parameters for bolt joint is sytematically studied. On the basis of analyzing the non-linear model of bolt joint and measuring its characteristics the simplified Iwan model is adopted to simulate the joint characteristics and the analytical model of bolt build-up structure is set up. Furthermore, the force-state mapping method is chosen to identify the bolt joint parameters and the corresponding test procedures are presented too. At last as a practical study case the non-linear stiffness and damping parameters of bolt joint are identified by the proposed method which can be used as the reference for identifying the non-linear joint parameters of the other bolt build-up structures. [ABSTRACT FROM AUTHOR]

On the basis of working principle and its characteristics of linear variable differential transformer (LVDT) displacement sensor, this paper put forward a method to deal with the nonlinear issue of output signals at both ends of the sensor using Chebyshev best approximation principle. The sensor's effective range is adaptively divided into linear and nonlinear regions, linear processing would be made for signals of two regions, respectively. The linear working range and the corresponding linear approximable straight-line function of the sensor are determined according to Chebyshev best approximation principle, while signals in nonlinear regions are linearized using rational B-spline function. A signal processor was designed based on MSP430 microcontroller and a test platform composed of a stepper motor straight-line units and a standard laser sensor was established. Experiments have been implemented to verify the feasibility of proposed method with 85 mm range of LVDT displacement sensor. The results show that this method can effectively improve the linearity and precision of the sensor and extend the working range of displacement sensor. [ABSTRACT FROM AUTHOR]

A mathematical model of Active Magnetic Bearing (AMB)-flexible rotor system is built in the paper. Supporting characteristic of AMB, unbalanced stationary responses of the system under control with different parameters and the influences of control parameter variation on system stability in rotating state were analyzed, and variable parameter control strategy based on rotation speed was put forward. The experimental setup for 5 DOF active magnetic bearing-rotor systems was established. The signal of the rotation speed was introduced into the digital controller, different control parameters were adopted in different rotation speed section, and dynamic characteristics of the system with variable parameter control strategy were investigated. Theoretical analysis and experimental results show that the variable parameter control strategy can meet requirements of low-frequency and high-frequency dynamic characteristics of the system synchronously, thus reducing unbalance vibration of the rotor effectively, and making for stably passing the critical speed of the rotor system. [ABSTRACT FROM AUTHOR]

To improve the applicability of the conflict delay model between left-turn vehicle and straight vehicle in the opposite direction at two-phase intersection, the conflict delay was studied on the basis of M3 distribution. M3 distribution of time headway for straight vehicle is more suitable than negative exponent distribution at signalized intersection. The queue delay of left-turn vehicle and the affect of the number of straight queue vehicles on conflict delay at the beginning of green were considered when M3 distribution was used in this paper. Then a new conflict delay model at two-phase intersection was put forward and it proved effective. The result shows that the conflict delay model improved closely meets with reality and it proved effective. It consummates the theory of existing conflict delay calculation and can provide the theoretical basis for setting up signal phases further. [ABSTRACT FROM AUTHOR]

According to the fact that the linear imaging model cannot explain the lens distortion, and to overcome the problem that the ordinary calibration methods are not. suit for the change of height and angle, based on the pin-hole model and the previous distortion correction, this paper builds up a mirror coordinates system to study the reflection relation of pixel and angle. By using trigonometric functions and distortion coefficient, the height parameter and angle parameter are introduced into the model, and then the non-linear model is obtained. Finally, under different kinds of situation, comparing with Tsai's method, the algorithm validity is verified. After changing the camera angle and height, the algorithm, which does not require re-calibration, is still with good accuracy and robustness. Thus, the algorithm can be applied to the engineering field. [ABSTRACT FROM AUTHOR]

The stability of a class of controlled systems with output time delay is analyzed in this paper. The range of time delay, in which the controlled system is stable, is confirmed by the stability switch theory. The time delay, which corresponds to the shortest decay time for step responses of the controlled system , is obtained analytically. According to time delay and filter design method, an effective controller is designed. And numerical simulations are performed on a cantilever beam to validate the proposed method. The results show that the decay rate of the system response is improved up to 80% after control, which ehhances control performance and stability of the system effectively. [ABSTRACT FROM AUTHOR]

By analyzing of 2D-Forward Modeling System characteristics, strengths, weaknesses, opportunities, threats are analyzed in this paper. The suitable testing strategies and testing methods of 2D-Forward Modeling System are made out after analyzing of these factors. Finally, effectiveness of trend analysis in formulating testing strategies and testing methods is verified through statistical analysis of the test results. [ABSTRACT FROM AUTHOR]

Due to efficient energy consumption, good stability and durability, lead extrusion dampers are widely used in passive vibration control of structures. In traditional lead extrusion dampers, the relative translational displacement between lead and shear block causes the plastic deformation of lead, which can consume much energy. In this paper, a new type of torsional lead extrusion damper is proposed, in which the relative rotational moment between the lead and the central shift is utilized. It is suitable for the vibration control of structures which use relative angular displacement for energy dissipation (such as the relative rotational angle between the beams and columns). It also can transform conventional energy dissipation mechanisms based on relative translational displacement into patterns using relative angular displacement by gears etc. Nonlinear finite element models for this torsional lead extrusion damper are established in ABAQUS based on the plane strain assumption. The simulation of turning processes of uniaxial and biaxial torsional lead extrusion dampers are discussed in detailed. The rectangular hysteresis curves of rotation-moment are presented, which illustrates the feasibility and effectiveness of torsional lead extrusion dampers in energy dissipation. The influence of flange height on maximum rotational moment is investigated. The parabolic evaluation formula of maximum rotational moment is presented for torsional lead extrusion damper. This study provides useful references for the conceiving of multi-axial torsional lead extrusion dampers. [ABSTRACT FROM AUTHOR]

Without noise, Interpolation method for discrete spectrum is an accurate correction method except rounding errors. However, the estimation accuracy can be greatly reduced when a signal corrupted with noise, and even turns Out to be mean- ingless. The paper investigates the influences of windowing and additive White Gaussian Noise on the accuracy of amplitude and phase based on interpolation method. Analytical expressions of the estimator variance for amplitude and phase correction are derived. Simulation results confirm the validity of the presented analysis. We suggest to avoid using interpolation method under the condition that the rectangular window is adopted to correct the phase when the normalization frequency error is small. [ABSTRACT FROM AUTHOR]

Single-axis rotation strapdown inertial navigation system (SINS) is studied in this paper. A new rotation scheme is proposed to solve the problem that carrier motion has not been isolated which would cause incomplete error compensation leading to a considerable error. Based on the principle of rotation SINS, the traditional four-position rotation-stop method is revised to get the new rotation scheme. By using the proposed method, the errors caused by carrier motion are periodically compensated. In this way, the accuracy of the system can be greatly raised and the complexity of the system can also be reduced. Computer simulation has been taken for vehicles and vessels, and the result shows that the program can depress the constant drift errors caused by the carrier motion without isolating the carrier motion. [ABSTRACT FROM AUTHOR]

This paper aims at overcoming the defect caused by illumination variations and shadows in the feature extraction of lane detection. Illumination invariant angle is obtained with entropyminimization method and it leads to a 1D, gray-scale image representation which is illumination invariant at each image pixel in log-chromaticity space. By finding line elements in Canny edge map, trivial edges in shadow sections are eliminated. Then, an improved voting scheme Hough transform is adopted to detect lines and the lane boundaries is represented with piecewise linear road model. The experimental results show the efficiency of proposed method in terms of invariance illumination, shadow removal, reliability and adaptability detection and real-time navigation. [ABSTRACT FROM AUTHOR]

This paper aims at improving the dynamic response and control precision of large inertia servo system with time-varying loading disturbance by using the scheme of explicit model prediction control (EMPC). The dynamic model of the large inertia servo system was directly established, the loading disturbance was observed by the dual unscented Kalman filter (DUKF) and the constraints such as system performance, input and braking power were considered. Thus, the EMPC control strategy was realized. The experimental results show that the response time is reduced with satisfactory control precision and the expected performance has been achieved. [ABSTRACT FROM AUTHOR]

Hybrid grid was widely used for the simulation of viscous flows with complex configurations. Hybrid grid deformation method becomes a major difficulty if hybrid grid can be applied for aeroelastic analysis. In this paper, a new mesh deformation method was developed,namely, an unstructured tetrahedral background grid was firstly generated, whose deformation was completed with the traditional spring network method including the torsion springs. Then a fast algebraic interpolation method between the background and the flow field grids was constructed to get the hybrid grid deformation. Because the background grid was only used for grid deformation, the number of the background grid could be decreased largely and its consuming time can be reduced largely. The deformation capability and efficiency of hybrid grid would also be improved. For the inconsistent of the object plane grids about the hybrid grid and background grid, the more than one background grid were generated, they have the same object plane grid and could cover the fluid domain and the solid domain. The method is firstly validated by the comparison with other methods. Then the method is applied for the three typical large deformation cases. Finally, the aeroelastic calculations for the standard wing AGARD 445. 6 and a wing with external store were given to show the availability of the developed hybrid grid deformation method. [ABSTRACT FROM AUTHOR]

To solve the problems of low power factor and large amount of harmonic component caused by uncontrolled diode rectifier in wind-power generation, the mathematical models for each part of inverter in wind-power generation with back-to-back topology were analyzed. Considering the control strategy of inverter at machine side and the net side, mathematical models of grid-connected converter and wind-power generation inverter were established. Simulations were implemented using Simulink software. The results have verified the correctness and feasibility of proposed control strategies in this paper [ABSTRACT FROM AUTHOR]

The centrifugal force and gyroscopic moment of angular-contact ball bearings are very large under high-speed conditions, which make the balls slide and severe wear. In this paper, the mechanics model for high speed ball bearings is set up with consideration of the radial load, axial load, centrifugal force and gyroscopic moment. The friction coefficients between balls and raceways and the minimum axial force to avoid sliding could be obtained by employing tractive force model and preventing sliding criterion. The results show that the friction coefficients vary within a certain range, and the minimum preloads should be heavier with the increase of rotational speeds and radial loads. [ABSTRACT FROM AUTHOR]

A mathematical model for computing the out-of-band (OOB) leakage radiation in NC- OFDM systems and the interference to the adjacent primary users (PUs) is presented in this paper. Based on this mathematical model, the optimal parameters could be obtained by solving the nonlinear programming (NLP) problem subject to secondary users (SUs)' spectrum overhead and PUs' occupancy rate r. The results showed the close relationship between the number of guard subcarriers and the parameters of input back off (IBO) as well as PU occupancy r and interference temperature tolerance. The simulation results have shown that, under the conditions of given PU occupancy r and PU interference temperature limit, the solution of proposed programming problem can be used to design the optimal system parameters for secondary users with the smallest number of guard subcarriers and the demand of system to the parameters of IBO. [ABSTRACT FROM AUTHOR]

A computational study performed for an artillery projectile using finite volume TVD schemes is described in this paper. First, computed Magnus moment coefficients for the spinning projectile have been compared with the available experimental data of SOCBT at Mach 3 and are found to be generally in good agreement. The results demonstrate that the method can provide an accurate and viable approach for this problem. Then, computational fluid dynamics (CFD) modeling and analysis of the spinning projectile with fixed canard have been conducted to determine the longitudinal aerodynamic coefficients. The analyses provide a detailed understanding of the effects of canard with different circumferential position on longitudinal aerodynamic coefficients at three supersonic speeds and various angles of attack. [ABSTRACT FROM AUTHOR]

In this paper, vehicle platoon spatially invariant interconnected systems are modeled as multidimensional systems by introducing spatial variables and spatial shift operators. The multi-object distributed H2/H∞ control method is investigated based on the model. Distributed output feedback controllers, which have the same structure as the plants, are designed to ensure that the systems have both good dynamic characteristic and system outputs to be as little as possible. Finally, vehicle platoon interconnected system is simulated by mass-spring model and the results demonstrate the correctness of the model and effectiveness of the method. [ABSTRACT FROM AUTHOR]

A prototypical serpentine belt drive system, which includes two pulleys, one tensioner and belt, is taken as an example, and slip rate between driven pulley and belt is measured and calculated. A mathematical model for calculating the slip rate is presented, and the slip rate is estimated for the proposed model. The estimated and tested slip rate agrees well, which validate the proposed model and experimental method. Taking density of the belt and frictional factor between belt and pulley as optimized variables, and slip rate as an objective function for optimization, the optimized density and frictional factor are obtained. The estimated slip rate using the optimized variables is reduced greatly compared to the original data. It is demonstrated that the method for optimally controlling the slip rate proposed in this paper is effective. The measurement and optimization method for slip rate is useful for controlling slip rate between pulley and belt in complex serpentine belt drive systems, such as accessory drive system at engine front end. [ABSTRACT FROM AUTHOR]

Based on the dynamic energy dissipation characteristics of nonlinear viscoelastic material, this paper established a mathematical model to analyze the shearing temperature-increase process of viscoelastic material under sinusoidal force, and designed a sine sweep experiment using the constrained damping vibration isolator. The acceleration changing history and the temperature-increase process were both recorded by experimental instruments. Comparing with the theoretical curve and the experimental curve, the similarity degree reached a high level of 90 percent and successfully proved the accuracy of the temperature-increase modal. The research conclusion explained the changing tendency of the isolator's natural frequency and isolation effect under different loading levels. Simultaneously, the vibration temperature-increase process provided references for nonlinear viscoelastic material damping tribute capability, thermal-damage and failure research during vibration. [ABSTRACT FROM AUTHOR]

The key structural parameters of the electronic controlled injector make a notable impact on the response time of the injector. This paper uses the non-dominated sorting genetic algorithm-TJ (NSGA-Ij ) method to optimize the parameters of the injector. The optimization is based on the multi-objective optimization platform, modeFRONTIER, and utilizes the hydraulic simulation software AMESim. Aiming at the delay functions of the opening and closing of the nozzle, the multi-objective optimization model is established and the optimization design of injector's key structural parameters is implemented. The results show that the delay of the nozzle opening is 0. 25 ms, which is reduced by 16. 7%; while the delay of the closing is 0. 78 ms, which is reduced by 15. 2%. [ABSTRACT FROM AUTHOR]

A urban water network was analyzed by the virtual reality technology in order to build a scene simulation platform of water network. And a new approach was appli on the study of water network system to overcome the shortcomings of traditional two-dimensional and three-dimensional models. The interaction and visual results were achieved in the virtual scene of the water network by integration of water network model and virtual scene. The objects in the virtual scene were built according to the standard atlas, which ensured that the model was with high accuracy. Then the model was optimized with relevant algorithms. The interactive virtual simulation platform of water network was built by programming in this paper and the scene simulation system of water network was realized, which was with the quality of verisimilitude, immersion and interaction. With the platform, the users can observe the water network lied underground directly, control the water network interactively and analyze the operation condition visually. [ABSTRACT FROM AUTHOR]

In order to improve the sensitivity of MEMS micro thermal shear stress sensor, the thermal effect of sensor is analyzed and the relevant mathematical physics model is established in this paper. Based on the model, the influences of hot film, insulation layer and cavity geometry on sensor's sensitivity are studied in theory. Comparing the theoretic analysis with the results based on numerical simulation by using the Fluent, the results show that the mathematical model is reasonable. [ABSTRACT FROM AUTHOR]

The frequency resolution is a very important parameter of Hilbert time-frequency spectrum analysis. Different frequency resolutions will lead to different analysis results for the same signal. But how to determine the best frequency resolution of Hilbert time frequency spectrum is seldom investigated by researchers. To determine the best Hilbert spectrum frequency resolution, a new performance estimation model is put forward for impact signal analysis in this paper. It can be used to determine the best frequency resolution of Hilbert time-frequency spectrum. In the end, signal analysis is used to testify the effectiveness of this model. [ABSTRACT FROM AUTHOR]

The diagnosis of composite fault occurred in mechanism is a difficult challenge at present. It is hard to diagnose the composite fault exactly and comprehensively due to the diversity and influence of faults. Multiwavelet has two or more base functions and many excellent properties. It might match two or more features of composite fault. The theory of multiwavelet supplies a reference for the solution of composite fault. The paper proposes an adaptive construction of multiwavelet using symmetric lifting. The kurtosis is selected to be the object of optimization. A new multiwavelet is constructed for the signal and used to decompose it redundantly. The distribution of relative energy for the characteristic frequency is computed. The composite fault is diagnosed by the sensitive frequency bands selected. Taking the composite faults of rolling bearing as examples, the effectiveness of the proposed method is proved. [ABSTRACT FROM AUTHOR]

This paper proposes a new scheme to construct Raptor codes that can provide unequal error protection (UEP) property. It utilizes joint optimization of UEP-LDPC codes and UEP-LT codes to improve the performance of more important bits (MIB). The density evolution (DE) formulas over binary erasure channels (BEC) are derived. By using the DE formulas, the constructed UEP-Raptor codes are optimized. Simulation results show that, compared with the previous UEP-Raptor codes, the proposed UEP-Raptor codes tan get better performances of both MIB and less important bits (LIB). [ABSTRACT FROM AUTHOR]

In order to take the rotating effect into consideration and predict the fatigue life of wind turbine system exactly, a fatigue life prediction model based on the rotationally sampled spectrum is proposed in this paper. Firstly, the rotationally sampled spectrum taking the rotating effect into consideration is deduced through the Fourier transformation and compared with the Von Karman spectrum (fixed point spectrum). Based on the rotationally sampled spectrum, a fatigue life prediction model which derives from the Palmgren-Miner (P-M) linear damage model is provided. Then the fatigue life analysis of a 1.25 MW wind turbine system is carried out. The results show that the energy of the rotationally sampled spectrum transforms significantly from the low frequency region to the high frequency region. Besides, multi-peaks also appear in the high frequency region because of the energy shift. The fatigue life prediction model based on the rotationally sampled spectrum can predict the fatigue life and evaluate the security of the wind turbine structure more exactly compared with the one based on the Von Karman spectrum, which will overestimate the fatigue life and is unsafe for the fatigue life prediction of wind turbines. [ABSTRACT FROM AUTHOR]

Aimed at the poor usability and low efficiency of UML modeling for enterprise software and application (ESA), an ESA oriented platform-independent model (ESA-PIM) based on extended UML is proposed to solve the problem. First, an integrated multi-view PIM model based on business objects was constructed by analyzing the characteristics of ESA. Then using the extended mechanism of UML, the new meta-classes, stereotypes and tagged values that describe the concepts and relationships in ESA-PIM were added into UML2.0 meta-model, and they were divided into different viewpoints in the extended UML meta-model. The ESA-PIM proposed in this paper realizes the semantic-based integration between various UML diagrams through the rich-semantic business objects, which improves the usability of UML and enhances the modeling efficiency of ESA. The feasibility and effectiveness of ESA-PIM were verified by an application case. [ABSTRACT FROM AUTHOR]

In order to analyze the effects of flywheel disturbance on dynamic characteristics of satellite frame structure, the dynamics model of satellite thin plate was established by travelling wave method in this paper, amt then the travelling wave dynamics model of satellite frame structure was established by combining travelling wave method and sub - structure technique. The simulation on dynamics characteristic of the satellite frame structure was carried out, and simulation results were compared with FEM results. It is showed that travelling wave method is accurate and effective in calculating the dynamic response of satellite frame structure, and it is more accurate than FEM results at mid to high frequencies. [ABSTRACT FROM AUTHOR]

Based on the theory of Donnell thin shells and the linear viscoelastic theory, by considering only the shearing deformation of viscoelastic core and adopting an assumption that the complex constant model is simulated as its energy dissipation characteristic, the integrated first order differential matrix equation of a sandwich conical shell with partially ring-shaped constrained layer damping treatment is derived in this paper. Since the circumferential curvature is a function of longitudinal coordinate, the coefficient matrix of sandwich conical shell is more complicated than those for cylindrical shell, then a semi-analytical method is developed to analyze the vibration and damping characteristics of a conical shell covered with partially ring-shaped constrained layer damping by means of the high precision direct integration technology and transfer matrix method. Numerical examples show that the proposed approach is effective. The effects of varies of parameters, such as coverage percent, on the natural frequency and dissipative factors of a PCLD sandwich conical shell are also discussed, which is also different from PCLD sandwich cylindrical shell. [ABSTRACT FROM AUTHOR]

In order to solve the problems that P2P traffic occupies most Internet bandwidth, and ISPs are difficult to execute management, and P2P system lacked self-optimization mechanism, the paper put forward a dynamic P2P traffic optimizing model based on ISP-join. In time sequence, this model describes a series of new methods, including autonomous domain division and management, network measurement and topology-aware, bandwidth and traffic feedback. Furthermore, a prototype system whose core is called DDP (domain discovery protocol) is developed. All of these methods can maintain autonomous domains and inter-domain information, improve inter-domain connection, and keep overlay network topology consistency. According to analysis and experiment validation, this model can achieve P2P traffic dynamic optimizing based on ISP-join. [ABSTRACT FROM AUTHOR]

The interference effects of neighboring dry-coal sheds and the internal coal stacks within the investigated dry-coal shed probably make the wind-induced responses of the dry-coal shed more complicated. In order to provide a systematic method to study the characteristics of dry-coal sheds with/without interference condition, wind-induced responses are calculated in this paper. The wind-induced dynamic responses are calculated in frequency domain using mode superposition method (CQC method), based on the wind pressure distributions on roof from wind tunnel tests on the rigid models. The wind-induced responses under no-interference conditions are firstly analyzed, and the results show that the responses of some typical nodes are largest when the structure is subjected to skew wind. Through the analysis of interference factors, the characteristics of interference effects under different interference conditions and wind directions are investigated, the cases where the interference effects are stronger are pointed Out. Meanwhile, it is found that interferences only had small effect on the largest total peak displacement for the control condition. [ABSTRACT FROM AUTHOR]