基于行车记录仪的港口物流统计检测系统设计

针对港口物流企业的行车信息统计系统的发展现状,运用GPS系统对港口物流行车信息进行实时记录,借助于GSM技术、互联网技术设备以及数据库存储查询平台,构建基于行车记录仪的港口物流统计检测系统,实现全面追踪港口物流配送车辆与物资的运输状况,帮助客户及时的了解到配送车辆与物资的具体位置与运输状态,同时也可以帮助港口物流企业随时查询全国各地的路径信息、经济信息以及资源管理信息,保障整个港口物流企业的统计监测体系的健康发展。

Design of motion control system of pipeline detection AUV

A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous underwater vehicle(PDAUV) is hereby designed to solve these problems when working with advanced optical,acoustical and electrical sensors for underwater pipeline detection.PDAUV is a test bed that not only examines the logical rationality of the program,effectiveness of the hardware architecture,accuracy of the software interface protocol as well as the reliability and stability of the control system but also verifies the effectiveness of the control system in tank experiments and sea trials.The motion control system of PDAUV,including both the hardware and software architectures,is introduced in this work.The software module and information flow of the motion control system of PDAUV and a novel neural network-based control(NNC) are also covered.Besides,a real-time identification method based on neural network is used to realize system identification.The tank experiments and sea trials are carried out to verify the feasibility and capability of PDAUV control system to complete underwater pipeline detection task.

Fault detection of large-scale process control system with higher-order statistical and interpretative structural model

Nonlinear characteristic fault detection and diagnosis method based on higher-order statistical(HOS) is an effective data-driven method, but the calculation costs much for a large-scale process control system. An HOS-ISM fault diagnosis framework combining interpretative structural model(ISM) and HOS is proposed:(1) the adjacency matrix is determined by partial correlation coefficient;(2) the modified adjacency matrix is defined by directed graph with prior knowledge of process piping and instrument diagram;(3) interpretative structural for large-scale process control system is built by this ISM method; and(4) non-Gaussianity index, nonlinearity index, and total nonlinearity index are calculated dynamically based on interpretative structural to effectively eliminate uncertainty of the nonlinear characteristic diagnostic method with reasonable sampling period and data window. The proposed HOS-ISM fault diagnosis framework is verified by the Tennessee Eastman process and presents improvement for highly non-linear characteristic for selected fault cases.

A virtual machine-based invasion detection system for the virtual computing environment

Under virtualization idea based on large-scale dismantling and sharing, the implementing of network interconnection of calculation components and storage components by loose coupling, which are tightly coupling in traditional server, achieves computing capacity, storage capacity and service capacity distri- bution according to need in application-level. Under the new server model, the segregation and protection of user space and system space as well as the security monitoring of virtual resources are the important factors of ultimate security guarantee. This article presents a large-scale and expansible distributed invasion detection system of virtual computing environment based on virtual machine. The system supports security monitoring management of global resources and provides uniform view of security attacks under virtual computing environment, thereby protecting the user applications and system security under capacity services domain.

Study of partial discharge characteristics at repetitive square voltages based on UHF method

Due to overvoltage produced by inverter output,inverter-fed motor insulation systems often experience fast electrical aging process,especially when partial discharge(PD) is incepted.Before putting into use,the PD detection should be performed on inverter-fed motors at repetitive square voltages to avoid the PD caused insulation deterioration when the motors are collected to inverters having specific characteristics.However,unlike PD tests at AC/DC voltages proposed in IEC 60270,the PD detection at repetitive square voltages is much more complex because of serious interference generated by impulse generator.To solve the problem,ultra-high frequency(UHF) method seems recommendable for its preferable signal-to-noise ratio(SNR).The chief aim of this study is to investigate PD pulse and statistical characteristics of turn-to-turn insulation for inverter-fed traction motors.A square-shaped Archimedes antenna,specially designed for the PD detection at repetitive square voltages of fast rise times,was used to perform PD tests on turn-to-turn insulation models.Time and frequency analysis results indicate that energy component of generator disturbance and PD pulses are mainly distributed in the 0-0.5 GHz and 0.6-1.5 GHz range,respectively.Based on the results,suitable filter was designed for power disturbance suppression.Additionally,resorting to the sensor unit(i.e.antenna and filter) and the PD test system,the PD statistical features at square voltages of different frequencies were obtained.Experimental results show that higher frequency will give rise,statistically,to PD of lower magnitudes distributing at smaller phases.A reasonable interpretation of this phenomenon was presented.Lastly,according to the PD statistical features,some suggestions for the PD detection system design,generator parameter optimization and the PD pulse extracting were given.The results of this work would be beneficial to the increase of the sensitivity when performing the PD detection on insulation systems for inverter-fed motors at repetitive square voltages and thus,improving the reliability of inverter-fed motors.