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With the application of encoders in artificial intelligence and aerospace, the demand for the miniaturization and high measurement accuracy of encoders is increasing. To solve this problem, a new absolute matrix encoder is proposed in this paper, which can realize 19-bit matrix coding by engraving two circles of matrix code, and has the advantages of fewer circles of code disk engraving and higher measurement accuracy. This article mainly focuses on the design of a new matrix code disk, encoding and decoding methods, decoding circuit design, Matlab simulation analysis, and experimental error analysis. The experimental results show that the encoder designed in this paper achieves ultra-small volume Φ30 mm × 20 mm, and the angle measurement accuracy is 2.57". [ABSTRACT FROM AUTHOR]

This paper modeled forced and free vibrations of an axially functionally graded (AFG) porous Rayleigh nanotube containing fluid surrounded by a viscoelastic foundation and acted by a traveling load. The material characteristics of the nanotube are graded longitudinally according to a power-law rule. Also, different porosity models in the longitudinal direction of the system are taken into account. The nonlocal strain gradient theory (NSGT) is applied to reflect the size-dependency of the model. The governing dynamic equation of the system incorporating the scale effects is derived by considering the effects of slip boundary conditions for the internal fluid. The vibration response of the system is obtained analytically. Several comparison studies verify this study's results. Various dynamic phenomena, such as cancellation and maximum free response, are discussed in different operating conditions of the system. Besides, a detailed parametric investigation is conducted to identify the effects of influential parameters, including material gradient, porosity coefficient, fluid velocity, scale parameter ratio, and substrate characteristics, on the dynamic behavior of the system. These research results could be valuable in designing and optimizing advanced nanosensors and targeted drug delivery systems. [ABSTRACT FROM AUTHOR]

Torsion deformable spatial beam and Costello theory are used to establish longitudinal-torsional-lateral coupled model of round balance rope. Based on Coulomb's friction law and longitudinal-torsional-lateral coupled model, the nonlinear coupled dynamic model with friction constraint of round balance rope is established. Meanwhile, time-varying multi-segments non–equal-length element transformation method (TMN-ETM) is proposed to save computation time. Then, natural frequencies, lateral responses are calculated when the coupled stiffness coefficient is zero. And the calculations are compared with traditional solution method. The results show that only about few areas in the round balance rope loop have large stress norm value, while the rest parts have small stress values. Besides, dynamic responses of the balance rope with balance rope suspension rotor releasing are conducted. When the static friction is converted to dynamic friction, the friction torque and angle acceleration will be mutated at the switching instants, and slip-stick transition in angle acceleration occurs. [ABSTRACT FROM AUTHOR]

Hafnium oxide (HfO2) multilayer films were prepared on a glass substrate by pulsed laser deposition, and a novel middle metal layer of Cu40Ag60 was developed. The influence of CuAg thickness and substrate temperature on structural, optical, electrical and morphological characteristics of HfO2/CuAg/HfO2 films were carefully investigated. Multilayer films with different CuAg thickness deposited at room temperature exhibit amorphous structures. As the CuAg thickness varies from 4 to 24 nm, the visible transmittance is kept between 63 and 80%, while the near-infrared transmittance and sheet resistance undergo significant reduction. Increasing the substrate temperature from 100 ℃ to 350 ℃ induces the transformation of HfO2 from amorphous to the crystalline structure, while the near-infrared transmittance and sheet resistance gradually increase. HfO2(50 nm)/CuAg(16 nm)/HfO2(50 nm) multilayer film grown at 150 ℃ exhibits optimal optical and electrical properties with the transmittance of 78.2% in the visible region, 17.7% in the near-infrared region, sheet resistance of 8.59 Ω/◻ and the highest figure of merit of 1.09 × 10–2 Ω−1, which are useful for their potential application in the field of heat mirror and optoelectronics. Furthermore, the possible mechanisms involved in obtaining low infrared transmittance and reduced sheet resistance were explored. [ABSTRACT FROM AUTHOR]

The fluorescence properties of multi-walled carbon nanotubes (MWCNTs) depend strongly on the microstructure, while their specific surface area increases dramatically at oxidation temperatures above 75 ℃. In this work, the microstructure evolution of MWCNTs was carefully studied by oxidation and amination over a narrow temperature range to clarify its effect on the fluorescence properties. Oxidation was performed by refluxing the MWCNTs in mixtures of sulfuric acid and nitric acid at the temperature from 75 to 95 ℃. After the oxidation treatment, the MWCNTs were further aminated with ethylenediamine. The microstructure evolution at each stage was determined by the results from transmission electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The results indicate that the microstructure undergoes significantly changes over this temperature range. With the increase of temperature, the oxidized nanotubes are gradually broken and introduced defect states, but the amidation degree and fluorescence emission show a trend of first increasing and then decreasing. The MWCNTs oxidized at 85 ℃ possess the tubular structure with the length of 100–200 nm and a large number of defect states, and exhibit the optimal fluorescence efficiency after amination. What's more, the possible mechanisms involved in the effect of microstructure evolution on fluorescence were also discussed. [ABSTRACT FROM AUTHOR]

Photoelectric encoders are widely used in high-precision measurement fields such as industry and aerospace because of their high precision and reliability. In order to improve the subdivision accuracy of moiré grating signals, a particle swarm optimization compensation model for grating the subdivision error of a photoelectric encoder based on parallel iteration is proposed. In the paper, an adaptive subdivision method of a particle swarm search domain based on the honeycomb structure is proposed, and a raster signal subdivision error compensation model based on the multi-swarm particle swarm optimization algorithm based on parallel iteration is established. The optimization algorithm can effectively improve the convergence speed and system accuracy of traditional particle swarm optimization. Finally, according to the subdivision error compensation algorithm, the subdivision error of the grating system caused by the sinusoidal error in the system is quickly corrected by taking advantage of the high-speed parallel processing of the FPGA pipeline architecture. The design experiment uses a 25-bit photoelectric encoder to verify the subdivision error algorithm. The experimental results show that the actual dynamic subdivision error can be reduced to ½ before compensation, and the static subdivision error can be reduced from 1.264″ to 0.487″ before detection. [ABSTRACT FROM AUTHOR]

Intelligent production line is the abbreviation of intelligent production line. Intelligent production line refers to a form of production organization that uses intelligent manufacturing technology to realize the production process of products. The actual manufacturing process includes different levels and links, and each step cooperates to create a high-efficiency production line. The intelligent production line includes 3 levels covering automation equipment, digital workshops, and intelligent factories and runs through 6 major links of intelligent manufacturing (intelligent management, intelligent monitoring, intelligent processing, intelligent assembly, intelligent inspection, and intelligent logistics). The emergence of the Internet of Things system has changed the way of information dissemination. The system combines radio frequency automatic identification and global positioning system technologies to achieve functions such as information exchange and processing, enabling information processing to be intelligent and improving resource utilization. Big data processing includes multiple data processing procedures, but data quality is the most important link in the entire process, and each data processing link will have an impact on the quality of big data. The big data processing process mainly includes data collection, data preprocessing, data storage, data processing and analysis, data display, data visualization, data application, and other links. This article aims to study the new progress of artificial intelligence algorithms for big data processing of IOT systems on intelligent production lines. It is hoped that through the development of intelligent production lines and big data processing technologies, ways to optimize artificial intelligence algorithms can be found. This study proposes a metadata replication method based on a separate replication strategy, which separates the replication process of the data operation log, each is independent, and shortens the data replication time. Combining the existing intelligent production line network platform in the laboratory and carrying out the research of the intelligent production line network state prediction system based on the neural network to design a network prediction system can prejudge the operation status of the intelligent production line network. The experimental results in this article show that when the Namenode mode is used to read data and when the number of clients reaches 8, the data processing basically remains unchanged. When the NCluster system reads data and when the number of clients is 6, the data is processed 1256. When the number of clients is 20, the data is processed 2100, the NCluster system will remain stable when the number of clients reaches 12, and compared with the Namenode system, it has obvious advantages. [ABSTRACT FROM AUTHOR]

HSR studies have been one of the most important issues in economic geography, transport economics and policy. However, prior studies give rare attention to its role on the technological innovation collaboration, which become increasing important nowadays. Using co-patent data of the State Intellectual Property Office (SIPO) database from 2000 to 2016, this paper investigates the role of HSR services in cross-city technological innovation collaboration. Empirical results show: 1) the intensity of cross-city technological innovation collaboration activities remains at a low level before the debut of HSR services in China, and the difference on this indicator between cities with and without HSR services is statistically insignificant. With the emergence of HSR network, cross-city innovation collaboration is booming and cities with and without HSR services show distinct trends. 2) HSR services play a significant positive role in stimulating the intensity of cross-city technological innovation collaboration activities of HSR cities. 3) megacities benefit most from the HSR network, and secondary cities also benefit from being connected to megacities by HSR lines. 4) The travel time between city pairs is significantly correlated with the intensity of collaborative innovation activities. Our results suggesting interregional innovation bonds, which implicitly featuring the channel of knowledge flow, are established or strengthened by high-speed transport investments. • We find that HSR services play a significant positive role in stimulating the intensity of cross-city technological innovation collaboration activities of HSR cities. • Megacities benefit most from the HSR network, and secondary cities also benefit from being connected to megacities by HSR lines. • The travel time between city pairs is significantly correlated with the intensity of collaborative innovation activities. [ABSTRACT FROM AUTHOR]

In citric acid-based carbon dots, molecular fluorophore contributes greatly to the fluorescence emission. In this paper, the nitrogen and sulfur co-doped carbon dots (N,S-CDs) were prepared, and an independent sulfur source is selected to achieve the doping controllability. The influence of sulfur doping on the molecular fluorophore was systematically studied. The introduction of sulfur atoms may promote the formation of molecular fluorophore due to the increased nitrogen content in CDs. The addition surface states containing sulfur were produced, and S element exists as –SO3, and –SO4 groups. Appreciate ratio of nitrogen and sulfur sources can improve the fluorescence emission. The photoluminescence quantum yields (PLQY) is increased from 56.4% of the single N-doping CDs to 63.4% of double-doping CDs, which ascribes to the synergistic effect of molecular fluorophores and surface states. The sensitivity of fluorescence to pH response and various metal ions was also explored. [ABSTRACT FROM AUTHOR]

Multi-cable parallel suspension system (MCPSS) is designed to lift a heavy object with rapid development of deep resources exploitation. An adaptive fuzzy backstepping control strategy combining with nonlinear disturbance observer is studied to synthetically control the posture for the underactuated MCPSS with tension constraint in this article. Firstly, a theoretical modelling of the MCPSS with boundary constraints is derived by the extended Hamilton's Principle. Secondly, the parameter uncertainties and time-varying disturbances are compensated by the fuzzy system and nonlinear disturbance observer, respectively. Thirdly, an adaptive fuzzy backstepping feedback controller based on the reference model is proposed to suppress vibration and control posture of the suspension platform. Finally, an Automatic Dynamic Analysis of Mechanical Systems (ADAMS) simulation and a numerical calculation are used to illustrate the theoretical model and the proposed control performance. [ABSTRACT FROM AUTHOR]

Mine friction hoisting system is a typical multi-body system composed of traction sheave, conveyance, hoisting rope, and balance rope. Hoisting rope is of large-scale and flexible tension, leading to large amplitude elastic vibration and huge tension fluctuation during hoisting movement. Balance rope is of small tension amplitude and bending modulus, undergoing significant curvature changes, large displacement, and large deformation. Considering the complex coupling vibrations between the moving hoisting rope and balance rope in the ultra-kilometer-deep shaft, a coupling modeling method of the variable-length hoisting rope with the variable-curvature balance rope is proposed. Based on the absolute nodal coordinate formulation(ANCF), the balance rope is modeled by non-equal-length and variable-number elements, and the hoisting ropes on both sides are modeled by variable-length and variable-number elements. A flexible rope vibration experiment platform is built in the laboratory to verify correctness of the proposed theoretical model. The experimental results are in good agreement with those in theoretical simulation. Besides, the nonlinear coupling dynamic behaviors of hoisting rope and balance rope in an ultra-kilometer-deep well are studied. It reveals the non-stationary phenomenon of hoisting rope and balance rope with a long-time range. Both sides of flat balance rope undergo large bending deformation and non-stationary response when transient resonance occurs in hoisting ropes. [Display omitted] • An ANCF-based coupling modeling method for friction hoisting system is proposed. • The non-equal-length and variable-length elements are developed with time-adjusting element numbers. • Numerical to experimental comparisons for flexible ropes are displayed. • Nonlinear dynamics of balance rope and hoisting rope are well described in kilometer shaft. [ABSTRACT FROM AUTHOR]

In the hoisting system of mine and elevator, the wire rope will generate rotational motion with unfixed axis, the rotation angle of which is a vital parameter for the system. Therefore, it is necessary to measure the rotation angle to evaluate the torsional state of the rope. This paper proposes an unfixed-axis wire rope rotation angle measurement method, which mainly includes two parts, the axis positioning of the rope and the rotation tracking process. Firstly, the axis positioning method of the rope is introduced. Then, the geometrical principle of rope rotation measurement and the framework of Lucas–Kanade tracking algorithm are explained. Finally, a simulation test and a rotation experiment verify the performance of the proposed algorithm, and the influence of axis positioning error and radius recognition error on the measurement are discussed. The proposed method provides an effective way for the measurement of wire rope. [Display omitted] • Target-less method for measuring the rotation of rope with unfixed axis is proposed. • Axis positioning of wire rope based on iterative solving is presented. • Geometric relationship of image coordinates during rotation is illustrated. • Factors affecting rotational measurement are analyzed. [ABSTRACT FROM AUTHOR]

Determining if there is any coal left in the coal mine skip unloading is a challenging problem. We propose a new object tracking method to provide new ideas to solve the problem of whether there is residual coal in the skip unloading. In this study, a fast vision-based measurement framework about new diamond search normalized cross-correlation (NDS-NCC), including a movement prediction part and a template tracking part, is used. Firstly, a diamond search method with fast adaptive coarse localization is proposed to overcome the time-consuming problem of NCC template matching process. Secondly, we incorporate a template updating strategies that allows targets to be tracked consistently. The performance of the NDS-NCC algorithm was tested on the bench and at the coal mine site for balancing cylinders and wire rope tracking. The results show that the NDS-NCC algorithm has better efficiency (7 ms/frame) and accuracy (0.4512 px) in the coal mine field application. [Display omitted] • A fast template matching method without identifiers is proposed. • An adaptive Kalman motion estimation method is proposed based on the actual working conditions. • A new template update mechanism is proposed. • The algorithm was verified by experimentally tracking different objects. [ABSTRACT FROM AUTHOR]

Modelling and control vibration is studied for the flexible guided lifting system in the presence of output constraints, input hysteresis, guided rope fault, etc. Flexible guided lifting system, subjected to external disturbances from the boundary disturbance or fluid interaction, is an inherent distributed parameter system with time-varying length and infinite dimensions. According to extended Hamilton's principle, the governing equation in the form of hybrid partial differential equations and ordinary differential equations is derived to reflect the dynamic response of such multiple ropes under the boundary disturbances and multiple constraints. Adaptive neural network control combining with backstepping technique is subsequently designed to suppress undesirable vibration and stabilise the system, where the neural network is provided as a feedforward compensator for the unknown hysteresis nonlinearities in the control input. Asymptotic stability and uniform boundedness of the system are guaranteed through the Lyapunov theorem, which indicates that all states are uniformly convergent by LaSalle's invariance principle. The original governing equation is solved numerically by using the finite difference method, where simulation results are illustrated to validate the efficiency of the hybrid partial differential equation and ordinary differential equation model and the adaptive stabilisation design. [ABSTRACT FROM AUTHOR]

A coupled dynamic modelling of the flexible guiding hoisting system is established, which includes the transverse-longitudinal-coupled vibration and the rotational vibration. Substituting vibrational energy of the system into Hamilton principle and applying the dynamic constraint, a distributed parameter mathematical model of the multi-rope system is derived. It is governed by coupled partial differential equations and ordinary differential equations (PDEs-ODEs), where the dynamic constraint in the form of an unknown moving force is the only connection between the hoisting conveyance and the guiding ropes. Based on Galerkin method, the dynamic response of the system is validated by numerical calculation and ADAMS simulation. Besides, an absorber with artificial intelligence optimization is proposed to reduce system vibration. The simulation result has demonstrated that a hoisting conveyance resonance can be observed when the external disturbance frequency is close to the system natural frequencies. Moreover, a vibration absorber can effectively diminish the resonant peaks of the first three orders of the guiding rope. [ABSTRACT FROM AUTHOR]

• GABP can effectively address the forward kinematics problems of Delta robot. • If the tolerance prediction error of ±0.05 mm is acceptable to the high precision control of Delta parallel robot system, mobile platform endpoint of the Delta robot system can achieve 97.75% accurate positing according to the Predicted Coordinate Pairs. • The proposed model overcomes weakness of traditional forward kinematics methods. Aiming at solving the problems of complex forward kinematics of Delta parallel robot and multiple solutions, and further improving celerity and accuracy of positioning for the spatial pose of the manipulator end effecter, in this paper, we present a method to kinematics solution of Delta parallel robot based on BP neural network. Taking the three-degree-of-freedom Delta parallel robot as the research object, according to analysis of its the kinematics principle, the basic BP neural network model and the optimized BP neural network model for kinematics solution of Delta parallel robot are simulated by using MATLAB, respectively. The results indicate that using BP neural network model improved by Genetic Algorithms to address the forward kinematics problems of Delta parallel robot is feasible, which can achieve the requirement of higher celerity and accuracy of Delta parallel robot control and avoid the shortcomings of traditional methods to a certain extent, furthermore, ensures the reliability of production safety. [ABSTRACT FROM AUTHOR]

A Fresnel–Kirchhoff integral can be used to calculate x-ray phase contrast images when the transmission function is known. Here expressions for image intensity are derived for objects with axial symmetry for an x-ray source with non-vanishing dimensions. An expression for the image intensity is given for an x-ray source whose intensity distribution is described by a Gaussian function, from which an expression for the limiting case of a point source of radiation is found. The expressions for image intensity are evaluated for cases where the magnification is substantially greater than one, as would be employed in biological imaging. Experiments using a microfocus x-ray tube and charge coupled device camera are reported to determine the capability of the method for imaging small spherical objects, such as gold particles, which might find application as contrast agents in biomedical imaging. [ABSTRACT FROM AUTHOR]

Organic light emitting diodes using a mixed layer of electron acceptor 3, 4, 9, 10 perylenetetracarboxylic dianhydride and electron donor copper phthalocyanine (PTCDA:CuPc) on indium tin oxide (ITO) anodes were fabricated. The device properties were found to be strongly dependent on the thickness of the PTCDA:CuPc film: both the power efficiency and the driving voltage of the device were optimized with a thickness of PTCDA:CuPc ranging from 10 to 20 nm. As compared to the conventional ITO/CuPc hole injection structure, the ITO/PTCDA:CuPc hole injection structure could remarkably enhance both the luminance and the power efficiencies of devices. A mechanism of static-induced, very efficient hole-electron pairs generation in mixed PTCDA:CuPc films was proposed to explain the experimental phenomena. The structural and optical properties of PTCDA:CuPc film were examined as well. [ABSTRACT FROM AUTHOR]

The hoisting rope has complex dynamic characteristics under external excitation during operation, characterized by large longitudinal movement and minor lateral oscillation. However, there are no appropriate approaches to acquire the dynamic displacement of the rope currently. In this study, a fast vision-based measurement framework, including initial value forecast (IVF) and target tracking based on Lucas–Kanade (LK) algorithm, called IVF-LK, is proposed to obtain the lateral-longitudinal displacement of the rope. Firstly, an IVF method is proposed to obtain the initial value of iteration, overcoming the problem of non-convergence of LK algorithm under large displacement. Secondly, a parameter update strategy makes the convergence speed of LK significantly improved. Then, the performance of IVF-LK algorithm was tested in the experimental bench, which reveal its superior capacity in rope-structure dynamic measurement both in efficiency and precision. Finally, a field experiment was implemented to analyze the dynamic displacement of the hoisting rope. • Vision-based measurement framework of hoisting rope is proposed. • Non-convergence problem of Lucas–Kanade algorithm under large movement is addressed. • The update strategy improves the convergence speed of the Lucas–Kanade algorithm. • Asynchronous movement of multiple hoisting ropes will occur in the hoisting system. [ABSTRACT FROM AUTHOR]

Traction systems are a good choice for high-rise lift systems, especially in deep wells. With increasing lift depth and weight, rope-guided traction systems have become an essential design methodology in the mine lift field. In this paper, a comprehensive mathematical model is established to simulate the dynamical responses of a rope-guided traction system with different terminal tensions acting on the compensating rope. The results and analysis presented in this paper reveal dynamical responses in terms of longitudinal and transverse vibration. Additionally, a wide range of resonances occurs in the target system. Differences in the dynamical responses between a traditional traction system and tensioned traction system are analysed in detail. Through comparison and analysis, it is determined that terminal tension plays an important role in the suppression of longitudinal vibration in a system. However, changes in the amplitude of longitudinal vibration are independent of terminal tension, which only affects longitudinal elastic elongation and does not affect the basic shape of longitudinal and transverse vibrations. Based on this analysis, it can be concluded that longitudinal vibration suppression can be achieved by applying proper tension on the compensating rope to ensure that it reaches a tensioning state. Continuing to increase terminal tension is not beneficial for the vibration suppression of a system. The results presented in this paper will serve as a valuable guide for the design and optimisation of traction systems. [ABSTRACT FROM AUTHOR]

(Zr 47 Cu 44 Al 9) 100−x Nb x (x = 0, 1, 2, 3, and 5 at.%) bulk metallic glasses (BMGs) were prepared by copper mould casting. The influence of Nb addition on glass-forming ability (GFA), thermal stability and mechanical properties of ZrCuAl alloys was studied. The GFA of Zr 47 Cu 44 Al 9 BMGs is enhanced obviously after the addition of Nb. The critical size of completely amorphous sample increases from 4 mm for Zr 47 Cu 44 Al 9 to 10 mm for (Zr 47 Cu 44 Al 9) 98 Nb 2 alloy. The average activation energy of crystallization is 505 kJ/mol for (Zr 47 Cu 44 Al 9) 98 Nb 2 BMG, which is larger than that of Zr 47 Cu 44 Al 9 BMG with 443 kJ/mol. The fracture strength and plasticity are sensitive to the Nb content. (Zr 47 Cu 44 Al 9) 98 Nb 2 BMG exhibits high fracture strength of 2397 MPa and prominent plastic strain of 13.2%, and multiple shear bands with high density were observed. Furthermore, the possible mechanisms involved in obtaining high GFA and large plasticity were explored. • The glass-forming ability of Zr 47 Cu 44 Al 9 alloys is enhanced obviously after the addition of Nb. The critical size increases from 4 mm for Zr 47 Cu 44 Al 9 to 10 mm for (Zr 47 Cu 44 Al 9) 98 Nb 2 alloy. • (Zr 47 Cu 44 Al 9) 100−x Nb x BMGs with low Nb content (i.e., x≤2) present remarkable plasticity, while alloys with large Nb content (x = 3, 5) display brittle fracture without any detectable plasticity. • (Zr 47 Cu 44 Al 9) 98 Nb 2 BMG exhibits high fracture strength of 2397 MPa and prominent plastic strain of 13.2%. [ABSTRACT FROM AUTHOR]

In this paper, a modelling method and an accurate numerical procedure are presented to simulate the dynamical responses of a multi-cable driven parallel suspension platform system. For such systems, the cables might become slack due to external excitations and due to the fact that cables can become tensionless when been pushed in longitudinal direction. In lateral and torsional directions, the constraint forces between the cables and platform can be positive as well as negative. This paper will deal with the non-smooth cable vibrations (in longitudinal, lateral and torsional directions) by taking into account the slackness of the cables. Firstly, the Lagrange equation with constraints is used to derive the equations of motion of the multi-cable suspension platform. Then, by expressing the equations of motion and constraint equations at velocity level, a non-smooth algorithm is used to numerically solve the equations. Finally, the numerical results are compared with an ADAMS simulation, and the two results agree well with each other. Moreover, the results in this paper significantly improve the numerical results used in the analysis of the dynamics for multi-cable systems which usually neglect the lateral properties of the cables. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Topological materials are a new and rapidly expanding class of quantum matter. To date, identification of the topological nature of a given compound material demands specific determination of the appropriate topological invariant through detailed electronic structure calculations. Here we present an efficient criterion that allows ready screening of potential topological materials, using topological insulators as prototypical examples. The criterion is inherently tied to the band inversion induced by spin-orbit coupling, and is uniquely defined by a minimal number of two elemental physical properties of the constituent elements: the atomic number and Pauling electronegativity. The validity and predictive power of the criterion is demonstrated by rationalizing many known topological insulators and potential candidates in the tetradymite and half-Heusler families, and the underlying design principle is naturally also extendable to predictive discoveries of other classes of topological materials. [ABSTRACT FROM AUTHOR]

This paper investigates the modified function projective synchronization between fractional-order chaotic systems, which are partially linear financial systems with uncertain parameters. Based on the stability theory of fractional-order systems and the Lyapunov matrix equation, a controller is obtained for the synchronization between fractional-order financial chaotic systems. Using the controller, the error systems converged to zero as time tends to infinity, and the uncertain parameters were also estimated so that the phenomenon of parameter distortion was effectively avoided. Numerical simulations demonstrate the validity and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

In order to enhance the fidelity, convenient and flexibility of swinging motion, the structure of incompletely restrained cablesuspended system controlled by two drums was proposed, and the dynamic response of the system under swinging and heaving motion were investigated in this paper. The cables are spatially discretized using the assumed modes method and the system equations of motion are derived by Lagrange equations of the first kind. Based on geometric boundary conditions and linear complementary theory, the differential algebraic equations are transformed to a set of classical difference equations. Nonlinear dynamic behavior occurs under certain range of rotational velocity and frequency. The results show that asynchronous motion of suspension platform is easily caused imbalance for cable tension. Dynamic response of different swing frequencies were obtained via power frequency analysis, which could be used in the selection of the working frequency of the swing motion. The work will contribute to a better understanding of the swing frequency, cable tension and posture with dynamic characteristics of unilateral geometric and kinematic constraints in this system, and it is also useful to investigate the accuracy and reliability of instruments in future. [ABSTRACT FROM AUTHOR]

Unacceptable vibrations induced by the nonlinear friction in a rotor system seriously affect the health and reliability of the rotating machinery. To find out the basic excitation mechanism and characteristics of the vibrations, a coupled bending and torsional nonlinear dynamic model of rotor system with nonlinear friction is presented. The dynamic friction characteristic is described with a Stribeck curve, which generates nonlinear friction related to relative velocity. The motion equations of unbalance rotor system are established by the Lagrangian approach. Through numerical calculation, the coupled vibration characteristics of a rotor system under nonlinear friction are well investigated. The influence of main system parameters on the behaviors of the system is discussed. The bifurcation diagrams, waterfall plots, the times series, orbit trails, phase plane portraits and Poincaré maps are obtained to analyze dynamic characteristics of the rotor system and the results reveal multiform complex nonlinear dynamic responses of rotor system under rubbing. These analysis results of the present paper can effectively provide a theoretical reference for structural design of rotor systems and be used to diagnose selfexcited vibration faults in this kind of rotor systems. The present research could contribute to further understanding on the self-excited vibration and the bending and torsional coupling vibration of the rotor systems with Stribeck friction model. [ABSTRACT FROM AUTHOR]

The dynamic responses of cable-driven parallel sinking platform are investigated considering the longitudinal–torsional coupled characteristics of the cable. The dynamic equations of the system are derived through the Lagrange equations, and the geometric matching conditions and the constraint forces at the interfaces between the cables and the platform have also been considered in the equations through Lagrangian multipliers. By neglecting the slack state of the cable, the numerical results of the mathematical model are obtained through Newmark-beta method after transforming the derived differential algebraic equations (DAEs) to a system of ordinary differential equations (ODEs). An ADAMS simulation is carried out, and the ADAMS simulation results agree well with the results obtained through Newmark-beta method. The results have shown that the lateral characteristics of the cables have a great effect on the torsional vibration of the platform, and by arranging the cables correctly will help to reduce the rotation of the platform. [ABSTRACT FROM AUTHOR]

The dynamic responses of parallel hoisting system with time-varying length and rigid guidance under drive deviation are investigated considering tension and torsion characteristics of the ropes. The variable-domain three-node elements of rope are employed and the corresponding differential algebraic equations (DAEs) are derived using Lagrange’s equations of the first kind. The slack situation of the rope is considered, and the dynamic equations which are systems of DAEs are transformed to ordinary differential equations (ODEs). The dynamic responses of tension, torsion, and acceleration are analyzed considering radius’ error of the drums, which indicates that the drive deviation between ropes can cause large influence on the tension difference and even cause one of the ropes to slack. However, the torsion of the corresponding rope is active. And unreasonable discordance between ropes should be controlled for the design and manufacture of drum on super deep parallel hoisting system. [ABSTRACT FROM AUTHOR]

Accurate monthly electricity consumption forecasting can provide the reliable guidance for better energy planning and administration. However, it has been found that the monthly electricity consumption demonstrates a complex nonlinear characteristic and an obvious seasonal tendency. Support vector regression has been widely applied to handle nonlinear time series prediction, but it suffers from the key parameters selection and the influence of seasonal tendency. This paper proposes a novel approach, which hybridizes support vector regression model with fruit fly optimization algorithm and the seasonal index adjustment to forecast monthly electricity consumption. Besides, in order to comprehensively evaluate the forecasting performance of the hybrid model, a small sample of monthly electricity consumption of China and a large sample of monthly electricity retail sales of the United States were employed to demonstrate the forecasting performance. The results show that the proposed hybrid approach is a viable option for the electricity consumption forecasting applications. [ABSTRACT FROM AUTHOR]

The flexibility of the suspension multicables and driven length difference between two cables cause the translation and rotation of the platform in the incompletely restrained cable-suspended system driven by two cables (IRCSWs2), which are theoretically investigated in this paper. The suspension cables are spatially discretized using the assumed modes method (AMM) and the equations of motion are derived from Lagrange equations of the first kind. Considering all the geometric matching conditions are approximately linear with external actuator, the differential algebraic equations (DAEs) are transformed to a system of ordinary differential equations (ODEs). Using linear boundary conditions of the suspension cable, the current method can obtain not only the accurate longitudinal displacements of cable and posture of the platform, but also the tension between the platform and cables, and the current method is verified by ADAMS simulation. [ABSTRACT FROM AUTHOR]

As a precision position sensor, the photoelectric encoder has difficulty avoiding eccentricity or tilt error in the industrial manufacturing and assembly process. At present, manual error correction is often used to adjust. The adjustment efficiency is low, and it has difficulty cooperating with other types of error compensation methods. In view of these problems, we proposed a photoelectric encoder eccentricity error detection and compensation method based on digital signal bandpass filtering that effectively corrects the signal deviation caused by the installation eccentricity in the output signal and judges the direction and magnitude of the eccentricity error to realize the encoding correction of eccentricity and inclination error of the device. The mathematical model of the eccentric error generation principle of the photoelectric encoder combined with the Lissajous figure was derived. We then demonstrated the design of a photoelectric encoder error detection platform to detect photoelectric encoders of different diameters in real time. Finally, using the advantages of field programmable gate array high-speed parallel processing, the error compensation algorithm was written into the development chip to improve the efficiency of processing the encoder output error signal. This method can adapt to the eccentricity error correction and compensation of different models of photoelectric encoders and can greatly improve the efficiency and accuracy compared with previous detection methods. [ABSTRACT FROM AUTHOR]

The topological properties of silicene and Sn film decorated with chemical functional groups (–H, –F, –Cl, –Br, –I) are investigated by the first-principle calculations. It is found that Sn films decorated with F, Cl, Br and I are topological insulators with sizable gap while the other combinations are normal insulators. The phase transition of X decorated silicene and Sn film was investigated by applying external strain. Our results pointed out that the normal insulators can transform into topological insulators with sizable gap under critical strain. The research provided new routes to design 2D topological insulator with sizable gap which has wide applications in next-generation spintronics devices. [ABSTRACT FROM AUTHOR]

Purpose: Microbeam radiation therapy (MRT) is defined as the use of parallel, microplanar x-ray beams with an energy spectrum between 50 and 300 keV for cancer treatment and brain radiosurgery. Up until now, the possibilities of MRT have mainly been studied using synchrotron sources due to their high flux (100s Gy/s) and approximately parallel x-ray paths. The authors have proposed a compact x-ray based MRT system capable of delivering MRT dose distributions at a high dose rate. This system would employ carbon nanotube (CNT) field emission technology to create an x-ray source array that surrounds the target of irradiation. Using such a geometry, multiple collimators would shape the irradiation from this array into multiple microbeams that would then overlap or interlace in the target region. This pilot study demonstrates the feasibility of attaining a high dose rate and parallel microbeam beams using such a system. Methods: The microbeam dose distribution was generated by our CNT micro-CT scanner (100 µm focal spot) and a custom-made microbeam collimator. An alignment assembly was fabricated and attached to the scanner in order to collimate and superimpose beams coming from different gantry positions. The MRT dose distribution was measured using two orthogonal radiochromic films embedded inside a cylindrical phantom. This target was irradiated with microbeams incident from 44 different gantry angles to simulate an array of x-ray sources as in the proposed compact CNT-based MRT system. Finally, phantom translation in a direction perpendicular to the microplanar beams was used to simulate the use of multiple parallel microbeams. Results: Microbeams delivered from 44 gantry angles were superimposed to form a singlemicrobeam dose distribution in the phantom with a FWHM of 300 µm (calculated value was 290 µm). Also, during the multiple beam simulation, a peak to valley dose ratio of ~10 was found when the phantom translation distance was roughly 4x the beam width. The first prototype CNT-based x-ray tube dedicated to the development of compact MRT technology development was proposed and planned based on the preliminary experimental results presented here and the previous corresponding Monte Carlo simulations. Conclusions: The authors have demonstrated the feasibility of creating microbeam dose distributions at a high dose rate using a proposed compact MRT system. The flexibility of CNT field emission x-ray sources could possibly bring compact and low cost MRT devices to the larger research community and assist in the translational research of this promising new approach to radiation therapy. [ABSTRACT FROM AUTHOR]

The long-term performance stability of organic solar cells (OSCs), as well as their high power-conversion efficiency, is necessary for their practical use. A stable OSC with the structure of ITO/buffer/donor/acceptor/cathode is presented. A thin layer of MoO3-doped PTCDA (molar ratio 1:1) is adopted as the buffer in CuPc/C60 organic heterojunction photovoltaic (PV) solar cells, resulting in four to five times longer lifetime. The CT complex of buffer layer plays a decisive role in improving the stability and abnormal efficiency changes. [ABSTRACT FROM AUTHOR]

Abstract: A stable organic solar cell with structure of ITO/buffer/donor/acceptor/cathode is presented. A thin layer (5nm) of MoO3-doped CuPc is adopted as the buffer in CuPc/C60 organic heterojunction photovoltaic (PV) solar cells, resulting in two times longer lifetime. The surface morphology of buffer layer plays a decisive role in improving the stability. [Copyright &y& Elsevier]

Purpose: Carbon nanotube (CNT) based field emission x-ray source technology has recently been investigated for diagnostic imaging applications because of its attractive characteristics including electronic programmability, fast switching, distributed source, and multiplexing. The purpose of this article is to demonstrate the potential of this technology for high-resolution prospective-gated cardiac micro-CT imaging. Methods: A dynamic cone-beam micro-CT scanner was constructed using a rotating gantry, a stationary mouse bed, a flat-panel detector, and a sealed CNT based microfocus x-ray source. The compact single-beam CNT x-ray source was operated at 50 KVp and 2 mA anode current with 100 μm×100 μm effective focal spot size. Using an intravenously administered iodinated blood-pool contrast agent, prospective cardiac and respiratory-gated micro-CT images of beating mouse hearts were obtained from ten anesthetized free-breathing mice in their natural position. Four-dimensional cardiac images were also obtained by gating the image acquisition to different phases in the cardiac cycle. Results: High-resolution CT images of beating mouse hearts were obtained at 15 ms temporal resolution and 6.2 lp/mm spatial resolution at 10% of system MTF. The images were reconstructed at 76 μm isotropic voxel size. The data acquisition time for two cardiac phases was 44±9 min. The CT values observed within the ventricles and the ventricle wall were 455±49 and 120±48 HU, respectively. The entrance dose for the acquisition of a single phase of the cardiac cycle was 0.10 Gy. Conclusions: A high-resolution dynamic micro-CT scanner was developed from a compact CNT microfocus x-ray source and its feasibility for prospective-gated cardiac micro-CT imaging of free-breathing mice under their natural position was demonstrated. [ABSTRACT FROM AUTHOR]

Summary Flavonoids and/or phenolic acids are the major components responsible for antioxidant capacity in fruits and vegetables. Recent research has shown that flavonoids are absorbed in humans, although the bioavailablity of these dietary components is not completely clear. Some epidemiological evidence demonstrates a reduced risk of cardio- and cerebrovascular diseases in subjects with a high fruit and vegetable (flavonoid) intake. Investigations performed in vitro or in vivo in experimental animals suggest that some of the flavonoids have chemopreventive effects against certain forms of cancers. Flavonoids are potentially beneficial to cardio- and cerebrovascular systems due to their antioxidant activity against low density lipoprotein (LDL) oxidation, inhibition of platelet aggregation, and protection against capillary fragility. Flavonoids showed anti-inflammatory, antiarthritic, and antiallergic activities in vitro, and, thus, may have potential applications in preventing and treating other diseases. [ABSTRACT FROM AUTHOR]

Moderate drinking of alcoholic beverages is associated with a lower risk of coronary heart disease. it is generally accepted that the ethanol itself is at least partially responsible for this association. However, whether red wine has any additional benefits is unclear since the epidemiologic studies addressing the additional effects of wine did not distinguish red from white. This review focuses on the differences between red wine and white wine with regard to their chemical components and biologic effects. Red wine contains considerably more flavonoids, particularly anthocyanins and proanthocyanidins, than white wine. Red wine, as well as its flavonoid constituents, has been shown to have antioxidant activities, to inhibit platelet aggregation, and to relax blood vessels. The data suggest that a moderate intake of red wine (1-2 drinks per day) may have potential health benefits independent of alcohol, and this warrants further clinical studies and epidemiologic investigations, in light of the dangers associated with alcohol consumption, it may be wise for some people to obtain the red wine flavonoids through consumption of fruits and vegetables that also contain these phytochemicals. Nutr Clin Care. 2000;3:76-82. [ABSTRACT FROM AUTHOR]

Millipedes (Diplopoda) comprise one of the most important groups of large soil arthropods in terrestrial ecosystems; however, their phylogenetic relationships are poorly understood. Herein, the mitochondrial genome (mitogenome) of Spirobolus bungii was sequenced and annotated, which was 14,879 bp in size and included 37 typical mitochondrial genes (13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), and 22 transfer RNA genes (tRNAs)). Most of the 13 PCGs had ATN (AT/A/T/G) as the start codon except for COX1, which used CGA, and most PCGs ended with the T end codon. By comparing the gene arrangements of the mitogenomes among Diplopoda species, rearrangement occurred between and within orders. In contrast to Narceus annularus, the mitogenome genes of S. bungii had consistent orders but were transcribed in completely opposite directions, which was a novel finding in Spirobolidae. Moreover, the phylogenetic relationships within Diplopoda, which were based on the sequences of 13 PCGs, showed that S. bungii was clustered with N. annularus, followed by Abacion magmun. This indicated that there might be a close relationship between Callipodida and Spirobolida. These results could contribute to further studies on the genetics and evolutionary processes of S. bungii and other Diplopoda species. [ABSTRACT FROM AUTHOR]

Objective. We introduce a robust image reconstruction algorithm named residual-guided Golub–Kahan iterative reconstruction technique (RGIRT) designed for sparse-view computed tomography (CT), which aims at high-fidelity image reconstruction from a limited number of projection views. Approach. RGIRT utilizes an inner-outer dual iteration framework, with a flexible least square QR (FLSQR) algorithm implemented in the inner iteration and a restarted iterative scheme applied in the outer iteration. The inner FLSQR employs a flexible Golub–Kahan bidiagonalization method to reduce the size of the inverse problem, and a weighted generalized cross-validation method to adaptively estimate the regularization hyper-parameter. The inner iteration efficiently yields the intermediate reconstruction result, while the outer iteration minimizes the residual and refines the solution by using the result obtained from the inner iteration. Main results. The reconstruction performance of RGIRT is evaluated and compared to other reference methods (FBPConvNet, SART-TV, and FLSQR) using projection data from both numerical phantoms and real experimental Micro-CT data. The experimental findings, from testing various numbers of projection views and different noise levels, underscore the robustness of RGIRT. Meanwhile, theoretical analysis confirms the convergence of residual for our approach. Significance. We propose a robust iterative reconstruction algorithm for x-ray CT scans with sparse views, thereby shortening scanning time and mitigating excessive ionizing radiation exposure to small animals. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) with strong visible fluorescence were synthesized via oxidation and amination. A large number of oxygen-containing surface functional groups contributing to fluorescence emission have been found, and the novel structure of carbon nanoclusters with the diameter of 20–30 nm are formed at the tips of MWCNTs. The fluorescent MWCNTs exhibit distinct excitation-wavelength dependence and pH response. Furthermore, the temperature sensitivity of fluorescence has been described carefully. The fluorescence intensity first increases and then decreases upon increasing temperature, and the maximum emission is achieved when the functionalized MWCNTs are dried at 150 °C. • Multi-walled carbon nanotubes (MWNTs) with strong visible fluorescence were synthesized by the simple method. • The novel structure of carbon nanoclusters with the diameter of 20–30 nm at the tips was observed. • The temperature sensitivity of fluorescent MWNTs was verified. [ABSTRACT FROM AUTHOR]

In order to analyse the system spatial vibration of compound biaxial and inter-shaft bearings during unbalanced excitation, the theory of rotor dynamics and bearing contact deformation are combined to establish a coupling system model of compound biaxial and inter-shaft bearings. Considering the moment of inertia, gyro effect, and structural damping, a one-dimensional beam model is used to perform the MATLAB numerical calculation of the coupling system to obtain the modal characteristics of the system, and based on the ANSYS simulation analysis of the three-dimensional model, a modal test is used to obtain the system modal shape and test frequency response function to verify the rationality of the coupling system model. Based on the Runge-Kutta iterative method and Hamilton's principle, the nonlinear amplitude-frequency response of the system is calculated while taking into account the influence of the compound biaxial eccentricity, as well as the stiffness and radial clearance of the inter-shaft bearing. The results show that the changes in the eccentricity of the compound biaxial and the structural parameters of the inter-shaft bearing cause the unbalanced excitation of the system, additional external load changes, and different coupled vibrations between the composite compound biaxial and inter-shaft bearings. Therefore, it is reasonable to match the structural parameters of the coupling system and improve the dynamic performance to avoid system resonance. [ABSTRACT FROM AUTHOR]

Microspherical ZnO composites were prepared by introducing carbon dots (CDs) in situ by a one-step hydrothermal method. The effects of precursor and calcination treatments on the microstructure and morphology, compositional features and triethylamine (TEA) detection were carefully investigated. The results show that the addition of excess urea promotes the formation of CDs, the produced UC-ZnO composite presents microspheres with relatively smooth surface after calcination, and the retained CDs form heterojunctions with ZnO. TC-ZnO composite produced by adding excess trisodium citrate displays bowl-shaped depressions on the surface. After calcination, the porous structures with large specific surface area and carbon incorporation are achieved. The two composites show improved gas-sensitive response and reduced detection limit for TEA. The sensitivity for 100 ppm TEA at the optimal operating temperature of 350°C is 357 for UC-ZnO and 526 for TC-ZnO sensor, which are 21% and 80% higher than that of pure ZnO, respectively. The TC-ZnO sensor possesses an excellent low detection limit of 32 ppb. The introduction of CDs effectively modulates the morphology and interface state of ZnO microspheres, and improves the gas-sensitive performance. [ABSTRACT FROM AUTHOR]

Since it is difficult for lateral stiffness of rope-guided rails to meet industry criteria in deep construction shaft, schematic diagrams of displacement suppression mechanisms (DSMs) are designed with a systematic approach demonstrated to reduce the lateral displacement of rope-guided rails in this paper. DSMs are simplified as planar four-bar and six-bar topological graphs based on topological theory. Each corresponding mechanical chain of these four-bar and six-bar mechanisms is divided into a rack, mechanical parts, prismatic, and revolute joints. An extended adjacency matrix is defined to represent the rack position, specific types of kinematic joints, and adjacency relationships between kinematic parts. Then, a symmetric vertex identification method is proposed with regard to planar 1-DOF (one degree of freedom) four-bar and six-bar topological graphs to get the sequences of prismatic joints for kinematic chains of DSMs. Finally, the alternative schematic diagrams of DSMs are obtained. The results show four-bar mechanisms with simple structure; few kinematical parts but less resident force are suitable for a mine shaft with small space and small swing. Six-bar mechanisms with two prismatic joints and three mechanical rack degree are applicable for wide shaft space in deep shaft, due to their stable structure and double resistant force. This development is helpful for DSM dimension synthesis design in future. [ABSTRACT FROM AUTHOR]

In this paper, dynamic characteristics of the symmetrical traction system with tensioned pulley acting on compensating rope is theoretically investigated. Due to the excitations from drum, the traction system will occur longitudinal and transverse vibration. In order to explore the differences between traditional traction system and tensioned traction system with different tensioned methods and seek the optimal method of vibration suppression, the damping cylinder and terminal tension acting on compensating rope between tensioned pulley and ground are placed. Caused by the change of the rope's property, the system will produce different dynamic responses. Here, the differential-algebraic equations (DAEs) are derived using Hamilton principle. The transverse and longitudinal nonlinear coupling of ropes are considered. The generalized- α method is selected to solve the DAEs. Based on the response characteristics of the system, the time-frequency characteristics with different terminal damping are obtained by CWT (continuous wavelet transform) and FFT (fast Fourier transform). From results, it can be seen that tensioned pulley plays an important role in suppressing transverse and longitudinal vibration of the symmetrical traction system compared with traditional traction system, especially by adding damping cylinder. The amplitude of system decreases exponentially with the increase of the terminal damping acting on tensioned pulley. Different running speeds of tensioned traction system are discussed. The results can inform the development of relevant mitigating strategies to minimize the effects of excessive vibrations. [ABSTRACT FROM AUTHOR]

To investigate the relationships between financial constraints, government subsidies, and corporate innovation, a semi-logarithmic fixed-effect panel model and mediation effect test were applied, based on the data of Chinese listed companies from 2007 to 2017. We find that (1) financial constraints suppress corporate innovation. (2) Government subsidies are targeted at bailing out firms facing financial constraints. (3) Government subsidies promote corporate innovation (4) Government subsidies partially offset the suppression of financial constraints on innovation. We contribute to the fields of public finance, corporate finance, and corporate innovation by: (1) justifying the government subsidies target strategy as a bailout of corporate financial constraints, (2) verifying the corporate-innovation promotion of government subsidies, thus justifying the efficiency of government subsidies, and (3) showing that different types of innovation benefit differently from subsidies, thus justifying subsidies as a structural innovation engine. [ABSTRACT FROM AUTHOR]

Pt-loaded curling-like Bi 2 WO 6 (BWO) microdiscs were fabricated via a simple one-step hydrothermal and impregnation route. Various characterization methods, such as XRD, EDS and TEM, were conducted to prove the successful Pt loading. Electron migration from the semiconductor BWO to the precious metal Pt was revealed by the blue shift of the Bi 4f and W 4f XPS peaks with the increase of the Pt loading amount and the ∼10-fold baseline resistance elevation of the BWO-based sensor by the Pt loading, proving the formation of Schottky junction. Among the pristine BWO and Pt-loaded BWO with different Pt loading amounts, 1 wt % Pt-loaded BWO exhibits the highest gas response of 209 in sensing 500 ppm triethylamine at 300 °C, a minimal selectivity coefficient of 130.6 against some typical interfering gases at the same concentration and a low detection threshold of 1 ppm. Additionally, the sensitization mechanism is discussed as the synergistic effect of noble metal catalytic effect and metal-semiconductor junctions. [Display omitted] [ABSTRACT FROM AUTHOR]

The modeling and control of the multi-rope parallel suspension lifting system (MPSLS) are investigated in the presence of different and spatial distributed tensions; unknown boundary disturbances; and multiple constraints, including time varying geometric constraint, input saturation, and output constraint. To describe the system dynamics more accurately, the MPSLS is modelled by a set of partial differential equations and ordinary differential equations (PDEs-ODEs) with multiple constraints, which is a nonhomogeneous and coupled PDEs-ODEs, and makes its control more difficult. Adaptive boundary control is a recommended method for position regulation and vibration degradation of the MPSLS, where adaptation laws and a boundary disturbance observer are formulated to handle system uncertainties. The system stability is rigorously proved by using Lyapunov's direct method, and the position and vibration eventually diminish to a bounded neighborhood of origin. The original PDEs-ODEs are solved by finite difference method, and the multiple constraints problem is processed simultaneously. Finally, the performance of the proposed control is demonstrated by both the results of ADAMS simulation and numerical calculation. [ABSTRACT FROM AUTHOR]