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Analysis of the harmful effects to buried oil pipeline from power line short-circuit fault

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The Journal of China Universities of Posts and Telecommunications 2012年第5期19卷 124-128页

作者： lu ying-hua MO Fan School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Based on the transmission line theory of the buried metallic structures, the concerned harmful effects to the buried oil and natural gas pipelines caused by the power line short-circuit fault are further discussed. A closed-form expression of the induced voltage caused by the short-circuit fault of the ultra-high voltage power （UHVAC） transmission line is given. The transmission line model of the buried pipeline is set up and a set of formulas for calculating induced voltage on the pipeline and the parameters of the buried pipeline in actual environment condition are given. At last, the characteristic of the harm^hl effects on the buried pipeline from the power line short-circuit fault are discussed.

关键词： ultra-high voltage (UHV) power line short-circuit fault oil pipeline transmission line model of the buried metallic structures

Design and implementation of high-speed real-time data acquisition system based on FPGA

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 61-66页

作者： WANG Xu-ying lu ying-hua ZHANG Li-kun Office of Academic Committee Beijing University of Posts and Telecommunications Beijing 100876 China School of Telecommunication and Network Technology Beijing University of Posts and Telecommunications Beijing 100876 China The Translation Department of the Second Artillery Troops of PLA Beijing 100820 China

The electromagnetic radiation will result in informa- tion leakage being recovered when computers work. This article presents a high-speed real-time data acquisition system based on peripheral component interconnect （PCI） bus and field programmable gate array （FPGA） for sampling electromagnetic radiation caused by video signal. The hardware design and controlling flow of each module are introduced in detail. The sampling rate can reach 64 Msps and system transfers speed can be up to 128 Mb/s by using time interleaving, which increases the overall sampling speed of a system by operating two data converters in parallel.

关键词： high-speed data acquisition FPGA PCI bus very-high-speed integrated circuit Hardware description language (VHDL) analog-to-digital converter (ADC)

Direct computation of multiconductor transmission line capacitance and charge distribution

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 119-124页

作者： XU Jun lu ying-hua ZHANG Li-kun School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China The Translation Department of the Second Artillery Troops of PLA Beijing 100820 China

The per-unit-length capacitance parameter of multiconductor transmission line （MTL） is commonly extracted with indirect matrix transform method, which is complex and time-consuming. To solve the problem, an improved method to directly compute the MTL capacitance is proposed, which can be applied in the transmission line structure with arbitrary shaped cross-section and arbitrary separate distance. This method imports voltage conversions and matrix operations to simplify the complexity, improves computational efficiency by about 600% with results as accurate as previous method. The novel method presents a clear charge distribution map of MTL, whereas precious method will experience a tortuous process to get charge distribution.

关键词： multiconductor transmission line capacitance matrix charge distribution

Eavesdropping the display image from conducted emission on network cable of a PC

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 78-84页

作者： DU Yu-lei lu ying-hua ZHANG Jin-ling School of Telecommunication Engineering Beijing University of Posts and Telecommunications

The display image of a PC can be reconstructed by using the conducted emission on the PC＇s network cable. The relevant signals which be used to reconstruct the original image are coupling from the radiation of the switching of red, green, blue （RGB） signals in PC. These pertinent signals are partly contained in the frequency region higher than 30 MHz in the conducted emission. From these findings, the near-field coupling principle from PC to the network cable is analyzed firstly. And then, a multi-conductor transmission model for the RGB signals which transmit in the network cable is proposed. In addition, the maximum safe distance is estimated by using this model. In order to check the validity of the estimating distance, the eavesdropping experiment is carried out to reconstruct the original display image. The results demonstrate that the blurred display image can be retrieved at the place of 29.5 m.

关键词： electromagnetic secure conducted emission unshielded twisted pair cables eavesdropping multi-conductor transmission model

Euclidean distance harmonic method for establishing theoretical MAPK/Erk signaling pathway in treated breast cancer line MCF-7

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 80-84页

作者： ZHANG Hong-xin lu ying-hua ZHANG Jin-ling School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Hierarchical clustering algorithms, such as Pearson＇s correlation, Euclidean distance, Euclidean distance harmonic, Spearman rank correlation, Kendall＇s tau, and City-block distance, were used to find the best way to establish theoretical MAPK/Erk signaling pathway on the basis of breast cancer line MCF-7 gene expressions. The algorithm constructs a hierarchy from top to bottom on the basis of a self-organizing tree. It dynamically finds the number of clusters at each level. It was found that only Euclidean distance harmonic is fit for the analysis of the cascade composed from a RAF1 （c-Raf）, a MKNK1, a MAPKK （MEK1/2） to MAPK （Erk） in breast cancer line MCF-7. The result is consistent with the biological experimental MAP/Erk signaling pathway, and the theoretical MAPK/Erk signaling pathway on breast cancer line MCF-7 is set up.

关键词： hierarchical clustering signaling pathway,Euclidean distance harmonic

Solid phase extraction of methomyl and thiodicarb from environmental water with an activated carbon cartridge and their determination by HPLC

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Journal of Environmental Sciences 2000年第1期12卷 100-104页

作者： Chen, Yan-Jun lu, ying-hua Liu, Jun Chen, Ya-Min Department of Chemistry Jining Medical College Shandong Jining 272113 China

A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.

关键词： HPLC solid phase extraction activated carbon methomyl thiodicarb CLC number: X592 Document code: A

Generation of orthogonal UWB shaping pulses based on compressed chirp signal

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 99-102页

作者： CHE Shu-liang ZHANG Hong-xin lu ying-hua HE Peng-fei College of Physics and Electronic Engineering the Centre University for Nationalities Beijing 100081 China School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This study investigates a novel method to numerically generate orthogonal ultrawide band （UWB） shaping pulses based on compressed chirp signal. First, a pulse template with less than 1 ns duration time, which is used to construct a Hermitian matrix, is produced with a compressed chirp pulse. Sub-nanosecond orthogonal pulses are then generated for UWB by using the Hermitian matrix eigenvectors. The simulation results show that the power spectral density distribution of the UWB shaping pulses met the constraint of Federal communications commissions （FCC） spectral mask. The shaping pulses not only have higher spectrum utilization ratio and very short time duration but also have excellent autocorrelation and cross-correlation properties, which is an advantage to reduce the interference between multiusers. Especially, a method to produce sub-nanosecond orthogonal UWB shaping pulses by using a relatively longer duration chirp signal is presented.

关键词： UWB shaping pulse spectrum utilization ratio interference between multiusers

Dual-band-stop filters with unsymmetrical T-shape DGS resonators

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 112-115页

作者： ZHANG Jin-ling ZHANG Hong-xin lu ying-hua ZHANG Li-kun School of Telecommunication Engineering Beijing University of Posts and Telecommunications Translation Department

A kind of dual-band-stop filter with an unsymmetrical T-shape defected ground structure （DGS） is proposed. The filter has two band gap centers at 4.9 GHz and 7.35 GHz, respectively, where the two centre frequencies are just the second and third harmonics 2.45 GHz. The filters with high band-stop performance and wideband spurious suppression can be achieved by cascading miniaturized unsymmetrical T-shape DGS. The attenuation of three-cascaded T-shape DGS filter is 30.77 dB at 4.9 GHz and 17.96 dB at 7.35 GHz respectively. The above experimental results are in good agreement with the simulation results, especially for the third harmonic.

关键词： DGS band-stop filter dual-resonant characteristics unsymmetrical T-shape

Design and analysis of quantized controllable doped left-handed materials

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The Journal of China Universities of Posts and Telecommunications 2011年第3期18卷 99-104页

作者： LIU Wen ZHANG Hong-xin WANG Hong lu ying-hua CHEN Nan MEN Shuo School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China Beijing National Railway Research and Design Institute of Signal and Communication Beijing 100073 China College of Electronic Information and Automation Chongqing University of Technology Chongqing 400054 China

Two kinds of controllable doped left-handed materials （DLHMs） were designed by inserting inductors and capacitors into the traditional left-handed material （LHM） as heterogeneous elements respectively, which are DLHM with inductors （LDLHM） and DLHM with capacitors （CDLHM）. The characteristics of transmission spectrum were studied by using finite-difference time-domain method （FDTD）. Compared with the traditional LHM, the resonance strength of the LDLHM is weakened and the pass-band is narrowed, but with the increase of the value of the inserted inductors, the bandwidth is expanded. As capacitors inserted into the LHM, the pass-band of the CDLHM is expanded, but the pass-band is shifted to low frequency and the bandwidth is narrowed with the increase of the value of the capacitors, meanwhile, a new generated pass-band is also shifted to low frequency. Therefore, a quantized controllable doped left-handed material can be achieved.

关键词： electromagnetics left-handed material pass-band capacitors inductors