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Zhang W.,Tongji University | Zhang W.,Shanghai University of Electric Power | Miao D.,Tongji University | Gao C.,Zoomlion Heavy Industry Science and Technology Development Co. | Yue X.,Shanghai University
Jisuanji Yanjiu yu Fazhan/Computer Research and Development | Year: 2014

Pawlak's rough set theory, as a supervised learning model, is only applicable for discrete data. However it is often the case that practical data sets are continuous and involve both few labeled and abundant unlabeled data, which is outside the realm of Pawlak's rough set theory. In this paper, a neighborhood rough sets based co-training model for classification is proposed, which could deal with continuous data and utilize the unlabeled and labeled data to achieve better performance than the classifier learned only from few labeled data. Firstly, a heuristic algorithm based on neighborhood mutual information is put forward to compute the reduct of partially labeled continuous data. Then two diverse reducts are generated. The model employs the two reducts to train two base classifiers on the labeled data, and makes the two base classifiers teach each other on the unlabeled data to boot the their performance iteratively. The experimental results on selected UCI datasets show that the proposed model are more effective to deal with partially labeled continuous data than some representative ones in learning accuracy. Source


Wang Q.-Y.,Harbin Institute of Technology | Cao D.-Q.,Harbin Institute of Technology | Yang J.-B.,Zoomlion Heavy Industry Science and Technology Development Co.
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2013

The vibration mechanism of a gear system was analyzed, and the anti-vibration principle as regards a damping ring device was elaborated. The axial vibration equations of a gear-damping ring system were established. The harmonic balance method was employed to obtain an approximate analytical solution which was used to compare with the numerical solution. On this basis, by using a set of typical data, the amplitude-frequency characteristic was discussed. The relationships between vibration reduction characteristics and the parameters of system were also discussed. Source


Wei J.,Zhejiang University | Du H.,Zhejiang University | Fang X.,Zhejiang University | Guo K.,Zoomlion Heavy Industry Science and Technology Development Co.
Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery | Year: 2010

The vehicle-generated road damage can be effectively reduced when the relevant parameters of hydro-pneumatic suspension in engineering vehicles are tuned reasonably. Multi-body dynamics model with ADAMS, hydraulic system model with AMESim and spectra of road surface roughness model with Simulink were established based on 4-DOF signal-axis vehicle model with consideration of the nonlinear characteristic of accumulator, fluid resistance, check valve and pipeline in the system. "95 percentage fourth power aggregate force" was used as the criterion for road-friendliness and co-simulation was achieved. The relation between road-friendliness and relevant parameters of interconnected hydro-pneumatic suspension was analyzed through co-simulation. In certain extent, the road damage coefficient first decreased and then increased with the increase of the initial pressure of accumulator and the diameter of damper hole in suspension cylinder. The road damage coefficient decreased with the increase of the total volume of accumulator and the inner diameter of pipe. The length of pipe had little influence on the road damage coefficient. Source


Yang H.,Zhejiang University | Liu W.,Zhejiang University | Liu W.,Zoomlion Heavy Industry Science and Technology Development Co. | Xu B.,Zhejiang University | Zhu X.,Zhejiang University
Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | Year: 2012

The electro-hydraulic flow matching control system with the electro-proportional valve and electro-proportional pump works in a synchronous control mode of the valve and pump. It eliminates the hysteresis between the pump and valve in the traditional load-sensing systems nearly. Closed-loop feedback control of pressure and preset pressure margin between pump and maximum load pressure are not needed. It reflects the combination of flexibility and efficiency of hydraulic systems, improving energy efficiency and control performance. The experimental prototype of 2-ton excavator with the electro-hydraulic flow control system is taken as the investigation subject. Energy consumption and dynamic characteristic are comparatively analyzed between the traditional load sensing hydraulic system and the electro-hydraulic flow matching hydraulic system. The controller with flow share capabilities is designed for electro-hydraulic flow matching control. Compared with the traditional load-sensing system, the electro-hydraulic flow matching hydraulic system has the same as with post compensation with anti saturation. The pressure margin is reduced by more than 0.6-0.7 MPa, and the energy consumption is decreased by 8%-10%. It can not only improve the dynamic characteristic and energy efficient, but also the system stability. © 2012 Journal of Mechanical Engineering. Source


Chaobin H.,Tongji University | Li W.,Tongji University | Hu C.,Changshu Institute of Technology | Xu W.,Zoomlion Heavy Industry Science and Technology Development Co.
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010 | Year: 2010

To meet the demand of real-time of CNC system based on Windows CE.NET, this paper describes interrupt architecture of CNC system based on Windows CE.NET. In accordance with the interrupt architecture, the paper achieves the CNC system interpolation control with IPC5387 timer card. Finally, according to the research of interrupt process, the paper analyses the reasons for delay and testes delay time. Experimental results show that IPC5387-timer-interpolation compliance with CNC system real-time requirements completely. © 2010 IEEE. Source

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