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Hao J.,Zhejiang Wanli University | Zhang W.,Zhejiang Wanli University | Ling M.,Beijingjiaotong University
Proceedings - 10th IEEE International Conference on Computer and Information Technology, CIT-2010, 7th IEEE International Conference on Embedded Software and Systems, ICESS-2010, ScalCom-2010 | Year: 2010

Under the research context of two axis digital control turntable, this paper has set up a mathematical model of control system of turntables. Proceeding from such model, it has made an analysis on the deficiencies of classical PID control during turntable control. Against the feature of PID parameters difficult to be tuned, the neural network is thus introduced in the optimizing process of turncontrol PID parameters, during which PID controller is designed based on BP network. In addition, the PID algorithm control based on BP network is simulated with results indicating PID controller designed so featuring high tracking accuracy, stable performance and strong robustness, which provides a solution to the problem of inadequate precision required by classic PID control as regards to the control precision. © 2010 IEEE.

Li Y.,Beijingjiaotong University | Li Y.,Zhoukou Normal University | Wang F.,Zhoukou Normal University | Zhu H.,Zhoukou Normal University | Zhu H.,Xian Jiaotong University
Qinghua Daxue Xuebao/Journal of Tsinghua University | Year: 2013

The problem of botnet, especially in the P2P context which makes the botnet have stronger abilities in survival, has become one of the major threats for network security. A fuzzy logic botnet defense model (FLBDM) was developed to deal with the problem which is made up of three components, detection, analysis, and counterattack. A logic detection model, FLDBM (fuzzy logic detect botnet model), was proposed based on the fuzzy logic theory, with the typical botnet procedures then analyzed by introducing honeypot network. The authentication botnet was used to counterattack. Both simulations and experiments demonstrate that FLBDM has high successful detection rates with low false alarming rates while effectively destroying botnets.

Wei J.,Aerospace Research Institute of Materials And Processing Technology | Sun H.,Beijingjiaotong University | Yang S.,Beijingjiaotong University
Advanced Materials Research | Year: 2012

After the CS-444 infrared ray carbon sulfur analyzer reducing and stabilizing the blank value, we use it for the initial measurement and second measurement, and the third measurement if necessary, we can get the blank value of the sulfur. The results show that the precision and accuracy are better.

Wu X.,Beijingjiaotong University | Lang S.,Beijingjiaotong University | Guo X.Q.,Beijingjiaotong University
Applied Mechanics and Materials | Year: 2013

This article proposes using passenger transportation energy intensity to measure the energy utility efficiency and energy-saving potential of the passenger transportation, uses the complete decomposition model to decompose the passenger transportation energy intensity from 1990 to 2007, and then investigate how various factors impact passenger transportation energy intensity. As is shown in the results, transportation structure increases passenger transportation energy intensity, while energy efficiency decreases it, however the decline is limited. Thus energy saving caused by adjustment of transportation structure is much more considerable. © (2013) Trans Tech Publications, Switzerland.

Shi H.,Beijingjiaotong University | Bai M.,Beijingjiaotong University | Bai M.,CAS Institute of Process Engineering | Zhang Y.,Beijingjiaotong University | And 2 more authors.
International Journal of Earth Sciences and Engineering | Year: 2014

In order to solve the problem of deformation monitoring of the shield excavation of adjacent bridge pier under the complex condition, quickly and with high precision, 3 d laser scanning technology is introduced. From the basic principle and key technology of three-dimensional laser scanning technology, this paper studied work processes of three-dimensional laser scanning technology in monitoring shield excavation of adjacent bridge pier, discussed acquisition of the scanning point cloud data, transformation of coordinate, noise reduction method of redundant information, and put forward the algorithm of three-dimensional modeling based on point cloud data, the different periods of point cloud data set up respectively into triangle mesh model, using the method of quadric surface fitting for noise reduction, through the comparison of model as a whole to get the value of bridge pier deformation, compared with the results of the traditional total station monitoring. Research showed that the threedimensional laser scanning technology in the shield excavation adjacent bridge pier monitoring method was feasible, and the result is reliable. Besides, the value of deformation by using three-dimensional model differed with the results of total station monitoring in 3 mm. The monitoring results meet the requirement for precision, with some practical value in engineering. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.

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