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Search Results: 1 - 10 of 82508 matches for " 侯培国 "
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电子设备和系统射频通道高功率微波电磁脉冲场—路综合防护方法综述
Overview of the HPM field-circuit integrated protection methods for electronic equipment and system RF-channels
 [PDF]

郑生全, 邓峰, 王冬冬, 冬云,
Chinese Journal of Ship Research (SR) , 2015,
Abstract: 高功率微波电磁脉冲辐射可以通过多种耦合途径进入敏感电子设备和系统,导致严重的干扰、扰乱甚至损坏,特别是通过天线耦合进入射频通道的电磁脉冲会破坏敏感器件。给出几种针对天线耦合的空间电磁脉冲场防护以及电路中敏感器件的电磁脉冲路防护新方法,探讨敏感系统的电磁脉冲场—路综合防护设计方法。利用专门设计的防护表面和防护模块,分别在天线前端对空间的电磁脉冲场和天线后端电路中的电磁脉冲电压或电流进行抑制,保护电路中的敏感模块免遭损坏,增加的场—路综合防护对工作信号的衰减控制在允许的范围之内。通过原理样件的测试表明,防护方法对带内和带外的高功率微波电磁脉冲具有良好的防护效果。
High power microwave electromagnetic pulse radiation may easily be coupled with sensitive electronic equipments and systems through different entrances, resulting in disturbance, break down, or even destruction. Worse still, when the pulse is coupled with antennas, sensitive devices could be destroyed while the pulse enters into RF channels. in this paper, several new protection methods for antennas against space electromagnetic pulse radiation field as well as for sensitive devices in circuit against high pulse voltage or current are investigated. Moreover, the field-circuit integrated with the above protection design methods are proposed. Protection surfaces and modules which lie at the front and rearward of antennas are specially designed to restrain the space electromagnetic pulse field and voltage or current on the circuit, thus protecting sensitive modules from damage. Meanwhile, the attenuation for the operating signal within the circuit is controlled in an allowable range. For validation, samples tests are conducted, indicating that the proposed methods provide descent protection for both in-band and out-band high power microwave electromagnetic pulse.
不同细菌对家蝇幼虫抗菌蛋白/肽的诱导效应
利霞,,施用晖,
应用昆虫学报 , 2006,
Abstract: 利用抑菌圈测量法和毛细管电泳研究、比较不同细菌对家蝇muscadomestical.幼虫抗菌蛋白/肽的诱导效应。结果表明,家蝇幼虫受细菌诱导后抗菌活性比对照都有不同程度的增加,同时不同细菌诱导表达样品对于相应的诱导菌均表现很高的抗菌活性。毛细管电泳图谱表明鼠伤寒
基于 Fisher 准则的单次运动想象脑电信号意图识别研究
Single trial classification of motor imagery electroencephalogram based on Fisher criterion

付荣荣,,李曼迪
- , 2018, DOI: 10.7507/1001-5515.201701040
Abstract: 为了实现脑机接口系统,对单次运动想象脑电信号的优化特征进行了提取与分类。针对运动想象脑电信号的特点,通过预处理得到脑电信号 Mu 节律成分,利用共空间模式算法在优化空间滤波下提取了运动想象脑电信号的特征。使用 Fisher 判别分析进行分类决策,并通过交叉验证与受试者操作曲线相结合的方法对分类性能进行综合评价。以交叉验证方式对应用空间滤波进行投影的特征维度确定问题进行深入讨论,评价结果表明本文方法在保证较高的准确率的同时可提高运行速度。基于优化的脑电特征进行运动想象意图分类,能够反映不同状态的差异并简化识别流程,为意图识别研究提供了一种准确高效的新方法。
In order to realize brain-computer interface (BCI), optimal features of single trail motor imagery electroencephalogram (EEG) were extracted and classified. Mu rhythm of EEG was obtained by preprocessing, and the features were optimized by spatial filtering, which are estimated from a set of data by method of common spatial pattern. Classification decision can be made by Fisher criterion, and classification performance can be evaluated by cross validation and receiver operating characteristic (ROC) curve. Optimal feature dimension determination projected by spatial filter was discussed deeply in cross-validation way. The experimental results show that the high discriminate accuracy can be guaranteed, meanwhile the program running speed is improved. Motor imagery intention classification based on optimized EEG feature provides difference of states and simplifies the recognition processing, which offers a new method for the research of intention recognition.
驾驶员视角和后视效应对交通流稳定性的影响分析
Stability analysis of traffic flow considering driver’s visual angle and backward visual effect

,洪嘉阳,余焊威,严晨
- , 2018, DOI: 10.11860/j.issn.1673-0291.2018.04.012
Abstract: 摘要 交通流跟驰模型是微观交通流仿真和交通安全评估的重要工具,在城市交通规划、交通运行宏观调控等方面广泛运用.传统交通流跟驰模型主要考虑车辆参数,对于驾驶员因素不够重视,本文将驾驶员视角引入全速度差(FVD)模型,研究基于FVD模型的扩展模型,结合驾驶员后视效应,利用线性稳定性分析扩展模型的交通流稳定性特点.通过将驾驶员视角用驾驶车辆体型参数进行数据量化,分析车辆体型参数对交通流稳定性的影响.仿真实验表明:本文研究的扩展模型在车距较小的情况下交通流稳定性要优于FVD模型;驾驶员对视角变化的敏感系数越高,整个交通流越稳定;驾驶员后视概率越高,交通流越稳定;对于大型车辆,车流高峰时期为其开辟专用车道能够提高该阶段交通流稳定性.
Abstract:Traffic flow following model is an important tool for microscopic traffic flow simulation and traffic safety assessment. It is widely used in urban traffic planning, traffic operation and macro regulation. The traditional car following model of traffic flow considering the main parameters of a vehicle, the driver factors not enough attention, this paper introduces the driver from the perspective of Full Velocity Difference (FVD) model of extended model based on FVD model, combined with the driver’s visual effect, the stability of traffic flow characteristics of extended model of linear stability analysis. The influence of vehicle shape parameters on the stability of traffic flow is analyzed by quantizing the driver’s angle of view with the body parameters of the driving vehicle. The simulation results show that the extended model in the case of smaller car traffic flow stability is better than the FVD model; the coefficient of sensitivity to the changes of view driver is high, the traffic flow is more stable; the higher the probability of driver’s visual, traffic flow is more stable; for large vehicles, traffic during the peak period for its development lane can improve the phase stability of traffic flow.
白三叶对桃园小气侯和桃品质的影响
,孟林,,福强,张志刚,崔桐华
草地学报 , 2006, DOI: 10.11733/j.issn.1007-0435.2006.04.013
Abstract: 研究在桃园种植白三叶(Trifoliumrepens)和清耕作业对桃园小气候及大桃品质的影响。结果表明白三叶区与清耕区比较,前者能够维持气温和地温、保持土壤水分,明显改善桃园小气候,为桃树生育提供适宜的小环境;增加果桃维生素C、可溶性糖和可溶性固形物含量,减少了可滴定酸含量白三叶区大桃品质明显好于清耕区,其中糖酸比增加6.18,显著地提高了大桃的口感。
家蝇抗菌肽的抑菌动力学研究及其机理初探
,韩晋辉,丽霞,,施用晖
中国生物工程杂志 , 2006,
Abstract: 利用鼠伤寒沙门氏菌针刺诱导家蝇幼虫表达抗菌肽,对抗菌肽的抑菌动力学进行研究,并通过抗菌肽样品对不同细菌动力学特性的研究出发对抗菌肽抑菌作用机制进行探讨。研究发现抗菌肽样品的活性与作用时间有关,24h内出现一到两个活性峰,同一抗菌肽样品对不同细菌的抑菌动力学有差异,抗菌肽的抑菌动力学机制应该与它的的抑菌作用机制有关。通过电镜观测、细胞磷代谢、紫外吸收物测定以及抗菌肽与细菌dna相互作用结果可知,微生物诱导家蝇表达的抗菌肽样品不仅能够造成细菌细胞的快速坍塌破裂而且能够破坏细胞核心,与dna结合作用。抗菌肽抑菌动力学的解释:微生物诱导产物中含有两类抗菌肽,一类抗菌肽能造成细胞膜的快速坍塌破裂形成第一个活性峰;另一类抗菌肽可进入细胞,破坏细胞核心,造成紫外吸收物大量外泄形成第二个活性峰。
跑酷运动在我国开展的动因及发展趋势研究
Study of Motivation and Development Trend of Parkour in Our Country
 [PDF]


Advances in Physical Sciences (APS) , 2014, DOI: 10.12677/APS.2014.24010
Abstract:
文章主要通过在中国期刊网收集相关研究资料,通过大量的一次文献和二次文献的查阅获得了大量宝贵的文献资料,对跑酷运动在我国开展的动因及抑制开展的因素进行分析总结,并通过现状在理论的视角下对跑酷运动未来在我国的发展方向进行展望分析,以期为我国跑酷运动的开展提供理论依据,对跑酷运动的发展方向提供参考。
The article summarizes and studies the Parkour’s motivation and inhibition factors through rele-vant research data from CNKI by consulting numbers of primary documents and secondary docu-ments. Besides, development direction of Parkour is analyzed theoretically according to the status quo, so as to provide theoretical basis for the start of Parkour, and to offer references for its de-velopment direction in the country.
IEPE加速度计电路噪声分析
Analysis of Circuit Noise in Integral Electronics Piezoelectric Accelerometer

杨哲,曹丽芳,王玉田,,李泓锦,程朋飞,潘钊
- , 2016, DOI: 10.16450/j.cnki.issn.1004-6801.2016.05.020
Abstract: 研究压电集成电路加速度计的主要噪声源,利用En-In噪声模型将内部噪声源等效输入端,实现了输入噪声和输入信号的直接对比,能容易得到噪声对信号的影响。将Y-Δ变换原理引入T型网络噪声分析,降低噪声分析难度。通过对电路噪声的分析,在宽频范围内推导出可用于计算IEPE加速度计电路本底噪声的公式。将理论计算值与PSpice软件噪声分析所得值进行了对比,证明二者具有良好的相关性,同时得出了各噪声源在输入端对总噪声的贡献,提出了在不同频段内降低总噪声的方法,为IEPE加速度计电路的低噪声设计、参数选择和性能优化提供了理论依据。实验样机的实际值与理论值的对比结果表明,此法对于IEPE加速度计电路低噪声设计具有应用价值。
This paper studies the main source of noise in an integral electronics piezoelectric (IEPE) accelerometer circuit. When the noise model allows the internal noise to be converted into the input source, the noise′s effect on the signals can be easily analyzed by the direct comparison between the input noise and input signal. Then, the noise analysis was simplified by introducing the transformation principle into the T-network noise analysis. The circuit background noise in the IEPE accelerometer within the broadband was derived based on the former analysis, which was verified by the PSpice software. Meanwhile, the method presented different contributions that various noise sources made on the total noise at the input and put forward a method of total noise reduction at different frequencies. These studies provide a theoretical basis for IEPE accelerometer circuit design, parameter selection and performance optimization in low noise. The comparison of the actual value with the theoretical value of an experimental prototype shows the efficacy of this method in reducing the IEPE accelerometer circuit noise.
中国12320公共卫生公益电话试点建设及效果
蒋燕,
中国公共卫生 , 2009, DOI: 10.11847/zgggws2009-25-12-66
Abstract: ?2000年以来,中国信息化建设进入快速发展阶段,据2008年6月统计,我国固定电话、移动电话以及网民数量均居世界第一[1].充分利用覆盖面广的通讯网络已势在必行.因此,信息产业部设立了以123开头的5位号码资源,作为政府部门统一使用的公益电话.2005年底,卫生部启用12320全国公共卫生公益电话号码,主要通过手机和座机来电、短信、E-mial和传真等方式,受理公众对突发公共卫生事件和违反有关公共卫生法律法规案件的举报和投诉、向公众提供有关政策法规和疾病预防控制、卫生保健等方面的咨询服务[2].按照“先行试点,稳步推进”的原则,确定了以北京市等9个试点省市.
图书馆事业必须与国民经济的发展相适应

中国图书馆学报 , 1991,
Abstract:
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