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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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

In this paper, an inverse kinematics issue of robot was studied based on the properties of Jacobi matrices. Especially, the cases with the redundancy and singularity of the matrix were investigated. Firstly, a method was proposed to solve the inverse kinematics. Then its applications were presented. Finally, some simulation experiments were carried out. The results provide a basic method for the programming and control of robot action. [ABSTRACT FROM AUTHOR]

Lossless data compression systems are prone to transmission errors, and the effect of bit errors presents a spreading trend as the decoding progresses, which limits its applicability in the areas such as noisy wireless channels and file systems that may be damaged. Lossless data compression algorithm LZW can be widely used in file formats such as GIF, PDF, and TIFF. In this paper, the redundancy of the LZW compressed data was used to propose a design scheme of the error repair algorithm, and present the relevant theoretical basis. This scheme was arranged to be compatible with the standard LZW algorithm, meaning that the files compressed by the proposed scheme could still be decompressed by the standard LZW decoder. Experimental results verify the feasibility and effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

In this paper, a 10 bit low power successive approximation register analog to digital converter (SAR ADC) was presented based on a time-domain comparator in 90 nm CMOS. Compared with conventional dynamic comparator, the time-domain comparator was arranged with differential multi-stage voltage controlled delay lines to convert voltage to time signal, and the time difference was sensed by a phase detector to reduce influence of common-mode various and static power consumption. And a partial monotonic switching strategy was employed to convert voltage in capacitor array, cutting down total capacitance and power consumption. Simulation results show that, with 1 V power supply, 308 kS/s at Nyquist sampling rate and 0.9 V signal scope, the ENOB can achieve 9.45 bit with 13.48 µW power consumption. [ABSTRACT FROM AUTHOR]

In this paper, a finite element analysis method was used to study the influence of annealing process on the thermo-mechanical reliability of Cu through-silicon via structure. Firstly, the processing technology of TSV structure with polyimide (PI) dielectric layer was introduced. Then, Von Mises stress distribution and Cu protrusion height of TSV structure, which used PI and SiO2 as the dielectric layer respectively, were compared under 400 °C for 30 min. On this basis, the parameters of PI-TSV were analyzed further, including size parameters of TSV (the thickness of dielectric layer and TSV diameter, height, pitch) and annealing process parameters (annealing temperature and time). The results show that, compared with SiO2-TSV, PI-TSV structure possesses better thermo-mechanical reliability after annealing, and it is an effective method for the Cu protrusion height and thermal stress reduction to appropriately increase the thickness of PI dielectric layer. [ABSTRACT FROM AUTHOR]

Compressed air energy storage also has shortcomings of low energy storage efficiency and long payback period. At present, most compressed air energy storage systems use adiabatic compression. When the compressed air is compressed, a large amount of power is consumed into heat. In this paper, a method was proposed, using the isothermal piston to absorb the heat in the compressed air and discharge the heat to the liquid at the bottom of the cylinder. Firstly, a dimensionless mathematical model of isothermal piston cooling was established. Then the dimensionless coefficients Ka and Xu affecting the heat transfer of isothermal piston were proposed and its influence on the isothermal piston compression system was analyzed. Finally, an example calculation was made with aluminum foam to form an isothermal piston, compression ratio of 7, speed 1 200 r/min, compression efficiency can be increased 11%. [ABSTRACT FROM AUTHOR]

With the continuous improvement of sensor technology and intelligent technology, intelligent proportional directional valve with built-in pressure sensor and temperature sensor are emerging. However, due to the large volume and slow response of the flow sensor, the flow sensor is difficult to be integrated into the proportional valve, so the flow information needs to be obtained indirectly by calculation. The traditional calculation method usually applies the empirical formula to the valve port flow coefficient. However, the proportional directional valve used in this study has a more complicated valve port shape and flow channel, which has a great influence on the valve port flow coefficient, and the traditional method is difficult to be directly applied. Therefore, the pressure sensors and the spool displacement sensor are used in this paper. The flow is calculated using the look-up table method and the flow feedback control is performed. This method can realize the flow dynamic control function of the proportional directional valve, thereby improving the versatility of the proportional directional valve. [ABSTRACT FROM AUTHOR]

The flow ripple has become one of the important factors that affect the performance of the piston pump. In this paper, an inline type double row axial piston pump was designed based on the study results of flow ripple, and the flow equation of the double row axial piston pump was established. With the different plunger parameters such as plunger size, number, and distribution, the flow ripple was calculated and analyzed, and the flow pulsation change rule of the double row axial piston pump was obtained. Taking the low non-uniform coefficient of flow as the optimization objective, the plunger parameters of the piston pump with the minimum flow pulsation were obtained, laying a theoretical foundation for the design of the inline type double row axial piston pump. [ABSTRACT FROM AUTHOR]

To solve the rating current falling problem of the linear motor induced by the demagnetization of permanent magnet at high temperature and the decrease of coil's cooling capacity, the material selection and structure optimization design are emphasized in the research area of linear motor. In this paper, the permanent magnet material, winding parameters, air gap structure and so on sides were focused on for the linear motor optimization design of 6 channels direct drive servovalve (DDV). Firstly, a finite element simulation model of the linear motor was established with Ansoft Maxwell software. And then, the parameters of winding structure were optimized, including the width and height of air gap structure, ampere turns of coil, considering the permanent magnet material. Finally, some simulation and experiment tests were carried out. The results show that, the high temperature resistance and output force of the optimized linear force motor can be significantly improved. The maximum working temperature can reach 200 degrees Celsius, and the driving force can over 100 N. [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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

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.)

High frequency burr in the pulse signal is one of the most important reasons to effect the detection accuracy and reliability of signal. This paper presented and practiced a real-time filtering method of state machine, and successfully applied to some speed detection for military vehicle. The method, using CPLD as hardware and driven by high frequency clock, detects transient signal, filtered out the short pulse and output the wide pulse, so as to realize filtering. This paper introduced in detail the principle and implementation method of the state machine, and analyzed the filtering characteristic of this method. This paper validated its feasibility and influence of filtering width changes on precision by simulating its application on square signal burr. [ABSTRACT FROM AUTHOR]

An error checking and correction (ECC) method based on Hamming code was developed to improve the conciseness in this paper. By means of utilizing the methods in information coding theory, the paper constructs the information matrix of multi-byte data. Then the coefficient matrix of ECC checking algorithm was designed and generated, which can be used to calculate the error-correcting codes through linear space transformation. Based on the ECC codes, a general error checking and locating algorithm was also proposed, which holds the characters of brief and strong computability. The process of coding, checking and correcting in embedded solid state storage system was also depicted. Then the VHDL described ECC algorithm was implemented based on Xilinx ISE environment. Experimental results show that the algorithm can succeed detecting errors of one bit or two, and correcting one bit error. [ABSTRACT FROM AUTHOR]

The transmission scheme of STBC combined with frequency domain equalization (FDE) was discussed in the cooperative communications system in this paper, and the decision feedback as well as interference cancellation techniques were employed to improve the performance of the scheme. STBC carried out in the relay nodes to obtain the transmission signal, then, spatial and FDE were executed to the received signal after the fast Fourier transform (FFT) at the receiver, and finally, the estimation of the transmitted information was obtained by hard decisions after inverse FFT operations. The transmission scheme can obtain the cooperative diversities supplied by the relay nodes, and the complexity of FDE is low, so a practical use can be achieved. This paper introduces a new algorithm with high performance by mainly using decision feedback as well as interference cancellation techniques to reduce the signal-to-noise ratio (SNR) loss during the FDE. Computer simulations show that the new scheme can effectively work, when the SNR is 12 dB, the new one can reduce the bit error rate from 10-2 to 10-3 in the cooperative communications system. [ABSTRACT FROM AUTHOR]

In modern electronic warfare, the GNSS repeater deception jamming has been an important method of jamming. With the research on satellite selection algorithm of GNSS repeater deception jamming, the jamming ability of repeater deception jamming can be improved. A satellite selection algorithm was proposed based on the satellite selection method of common GNSS positioning and PDOP contribution of single satellite. The simulations were carried out based on the pseudorange single positioning method with the least-squares algorithm, under the static and dynamic conditions respectively. And the receiver attacked by repeater deception jamming with single satellite was simulated under both static and dynamic conditions. The simulation results show that the satellite selection algorithm for repeater deception jamming proposed in this paper can provide the theoretically optimal star selection result with high probability. [ABSTRACT FROM AUTHOR]

A new type of flip-line coplanar electromagnetic band-gap (EBG) power supply layer structure was proposed in this paper, and the SSN suppression characteristic simulation analysis and practical application test were carried out. Maintaining the metal connection line gap width of 0.2 mm unchanged, four coplanar EBG power supply layer structures were designed with the design width of 0. 1, 0. 2, 0. 3, 0. 4 mm respectively. The simulation results show that the cutoff frequency of the coplanar EBG power supply layer with the width of 0. 2 mm is the lowest, and the relative band width is higher and the relative characteristic is the best. A coplanar EBG power supply layer with a metal cable width of 0. 2 mm was used to fabricate a PCB based on the printed circuit board process. And the actual test was carried out by the vector network analyzer (VNA). The suppression characteristic curve obtained is basically consistent with the trend of the simulation curve, verifying the validity of the design. [ABSTRACT FROM AUTHOR]

To provide customers with Internet remote services, cloud computing focuses on a large number of computing resources, storage resources and software resources. As cloud computing users, information resources are highly centralized, so the risk of cloud computing security incidents is much higher than the traditional application. Honeypot system can effectively capture the cloud traffic in the attack traffic. However, it is still difficult to develop seductive, protective, and deceptive honeypot systems for cloud computing security development. In this paper, a way was proposed to automatically isolate attack traffic from a real cloud computing server for a honeypot server. The honeypot system was isolated from the real cloud server by creating a virtual machine for a honeypot network server, allowing the honeypot server to have the same memory and storage devices as real cloud computing servers and monitoring the network traffic through OpenFlow. When a visitor visits the server normally, the switch can route the visitor's access request to the real server. When a visitor is marked as a suspicious attacker by IDS, the switch can recalculate the routing path and route the attacker's request to the developed honeypot. [ABSTRACT FROM AUTHOR]

Rectangular cavity is an essentially geometric structure of aircraft target, like inlet duct. As deep rectangular cavity is one of the most important scattering sources of concealed aircraft and the important identifying characteristics of this kind of target, it has significant meaning and practical applications in the research of scattering center modeling. In this paper, to design a high-precision scattering center model, a scattering center model of electrically large deep rectangular cavity was studied, utilizing ray tracing to determine the location of the multiple reflections of equivalent scattering centers, using the data of full-wave numerical method to accurately estimate the amplitude parameters of the scattering centers. In this model, there set some physical properties and a direct relationship between its parameters and the geometric parameters of cavity for the actual usage of model easily. The validated results indicate that scattering center model can precisely simulate the wave of the radar cross section and the high resolution range profiles of the electrically large deep rectangular cavity targets. [ABSTRACT FROM AUTHOR]

Point features are mostly extracted in feature based visual simultaneous localization and mapping to estimate camera poses when a robot moves in an unfamiliar environment. However, camera trajectories cannot be estimated accurately if the environment information is not abundant. In this paper, a visual odometry was proposed based on point and line features for RGB-D camera in the environment lacking of feature points. Bundle adjustment (BA) is widely used in estimating camera poses and feature positions. An unavoidable problem of BA with Euclidean coordinates or inverse depth is ill convergence under certain conditions. So a solution was proposed, that integrates parallax bundle adjustment and BA with line features to minimize back-project error. Finally, the proposed approach was compared with other feature based simultaneous localization and mapping (SLAM) system on the dataset TUM. The experiment results show that the proposed approach improves the performance in real scenes lack of point features. [ABSTRACT FROM AUTHOR]

To measure absolute length, the synthetic wavelength methods must construct a long enough synthetic wavelength made use of several single wavelengths, and make integer of the interference order be zero or a deterministic value. However, it is not easy to find corresponding wavelengths with appropriate values and high wavelength stability in practice. In this paper, a synthetic wavelength absolute measurement method was presented, adopting three high frequency stability lasers to form the synthetic wavelength chain. The measurement equations as well as the transition conditions between grades were derived. And a corresponding phase shift interference optical path was built to make high precision measurement for the absolute length value of the sample. The experiment and error analysis results show the measurement uncertainty is about 3 nm (a t 0. 3 m sample). In this method the requirement for initial measurement accuracy of the length is low and the measurement range is only limited by the length of the interferometric optical path. [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.)

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.)

The anti-symmetric thermoelastic instability model was developed to calculate the critical speed with the sliding condition of the perturbation fixed on friction components. The influence of material parameters such as elastic modulus and Poisson's ratio on thermoelastic stability of the friction system was studied. The model was verified by the finite element solution of Yi Yun-bo and Zhao Jianxin. The results show that the deformed discs have great influence on the process of shifting, however little effect on the creeping condition. Among the three kinds of friction discs, paper-based friction discs have the best thermoelastic stability, while the Cu-based friction discs are the worst. The critical speed increases with the increase of the specific heat, thermal conductivity of steel discs and thermal expansion coefficient of friction discs. On the contrary, the critical speed decreases with the increase of the other material parameters. Under the premise that the parameters of the separator discs remain unchanged, the stability of the friction system can be improved by decreasing the specific heat, Poisson's ratio, Young's modulus and thermal conductivity, meanwhile increasing the coefficient of the thermal expansion. [ABSTRACT FROM AUTHOR]

Branch (assembly mode or circuit) identification is a way to assure motion continuity among discrete linkage positions, which is the most fundamental issue among the mobility problems that may also include sub-branch (singularity-free) identification, range of motion, and order of motion. Branch analysis becomes more complex in spherical or spatial linkages. In this paper, an automated branch identification method was proposed based on discriminants of kinematic equations and the concept of joint rotation space (JRS) to analyze the branch formation of a spherical six-bar linkage. And an automated identification algorithm was presented to rectify the motion of a spherical six-bar linkage. The proposed method is general and conceptually straightforward. It can be applied for all linkage inversions. Examples were employed to illustrate the application of the proposed method. [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.)

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.)

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.)

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.)

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.)

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.)