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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

下垫面变化及雨型对珠海机场片区内涝影响研究

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中国农村水利水电 2024年第6期 132-139页

作者：许浩霆鲁华英占雪晴李佳佩高超张童浩北京师范大学珠海校区粤港水安全保障联合实验室广东珠海519087 北京师范大学自然科学高等研究院广东珠海519087 北京师范大学水科学研究院北京100875 珠海机场集团有限公司广东珠海519087 珠海市规划设计研究院广东珠海519087 广东省滨海地区防灾减灾工程技术中心广东珠海519087

在极端气候和城市化影响下,城市暴雨内涝问题日益严重。为有效解决弱水力梯度珠海机场片区的内涝问题,提高机场运行安全,研究基于InfoWorks ICM模型对机场片区下垫面变化及不同雨型暴雨下的管网排水能力、地表淹没情况及内涝风险等级进... 详细信息

在极端气候和城市化影响下,城市暴雨内涝问题日益严重。为有效解决弱水力梯度珠海机场片区的内涝问题,提高机场运行安全,研究基于InfoWorks ICM模型对机场片区下垫面变化及不同雨型暴雨下的管网排水能力、地表淹没情况及内涝风险等级进行分析,以期评估现有改造工程的内涝防治效果,并探究机场在不同重现期不同雨型暴雨条件下的适应能力,从而为未来的防治策略提供科学依据。研究结果显示,模型模拟水深与实测积水深度的偏差约为10%,验证了该模型在分析区域内涝特征上的可靠性。机场工程改造后,研究区域的内涝风险显著降低,不同风险等级的区域面积大幅减少,应对不同雨型的能力显著增强。特别是在百年一遇的降雨事件中,工程改造显著优化了管网性能,未满管段的比例增至58.08%,超负荷管段的比例从49%降至16.33%,从而使研究区内涝面积缩小88%、积水深度超50 cm的区域面积缩小85%。此外,当雨峰与潮位峰值同时出现时,随着降雨重现期的增加,尤其是5至50年一遇降雨事件,内涝风险随雨峰位置后移增大。机场工程改造提高了对中心型和延后型雨型的适应性,减少了有压管段的占比,显示出改造工程在提升机场抵御极端降雨事件能力方面的有效性。尽管如此,研究区内仍存在局部低洼地带和内涝风险,需持续关注并推进内涝点的整治工作。

关键词：内涝模拟雨型淹没面积管网负荷 InfoWorks ICM

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