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捷联惯性测量装置角速度通道动态特性辨识 被引量:1
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作者 侯心主 姚宏瑛 《测控技术》 CSCD 2015年第10期122-125,129,共5页
动态特性是评价捷联惯性测量装置的核心技术指标。以某一型号光纤捷联惯性测量装置(含减振器)为研究对象,通过角振动试验和数据分析,结合频域子空间算法与遗传算法,建立了基于捷联惯性测量装置整机角速度通道传递函数模型,为捷联惯性测... 动态特性是评价捷联惯性测量装置的核心技术指标。以某一型号光纤捷联惯性测量装置(含减振器)为研究对象,通过角振动试验和数据分析,结合频域子空间算法与遗传算法,建立了基于捷联惯性测量装置整机角速度通道传递函数模型,为捷联惯性测量装置整机动态性能应用评估奠定了技术基础,方法得到了比传统方法更好的结果,更适合实际工程应用。 展开更多
关键词 捷联惯性测量装置 速度通道 动态特性 频域子空间算法 遗传算法
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浓淡煤粉燃烧器双通道速度差对NOx排放的影响 被引量:3
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作者 安恩科 杨震 +1 位作者 宋谦 周海珠 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第4期537-539,共3页
对350 MW电站四角切圆煤粉锅炉燃烧过程和煤粉燃烧器气固两相流的数值计算表明,常规浓淡煤粉燃烧器的双通道速度差为6~9 m·s^(-1),因此,提出了等速型浓淡煤粉燃烧器的概念.等速型浓淡煤粉燃烧器比常规直流煤粉燃烧器可减少21.8%的... 对350 MW电站四角切圆煤粉锅炉燃烧过程和煤粉燃烧器气固两相流的数值计算表明,常规浓淡煤粉燃烧器的双通道速度差为6~9 m·s^(-1),因此,提出了等速型浓淡煤粉燃烧器的概念.等速型浓淡煤粉燃烧器比常规直流煤粉燃烧器可减少21.8%的NO_x排放,比常规浓淡煤粉燃烧器也可降低11.3%的NO_x排放. 展开更多
关键词 :煤粉燃烧器 通道速度 风煤比
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高速列车双通道速度传感器故障检测与隔离研究 被引量:11
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作者 牛刚 曹雪杰 秦肖肖 《仪器仪表学报》 EI CAS CSCD 北大核心 2019年第1期158-165,共8页
高速列车双通道速度传感器在随列车高速运行时受粉尘、振动、温度变化等因素影响,易出现车轴故障检测虚漏警或误诊等问题。现阶段工程中常利用测试对比等方法检测速度传感器状态,但无法及时监测且易产生虚报警。因此,利用改进主元分析法... 高速列车双通道速度传感器在随列车高速运行时受粉尘、振动、温度变化等因素影响,易出现车轴故障检测虚漏警或误诊等问题。现阶段工程中常利用测试对比等方法检测速度传感器状态,但无法及时监测且易产生虚报警。因此,利用改进主元分析法(PCA)和改进重构贡献图法(IRBCP)建立全新的速度传感器故障检测隔离系统。首先,利用可检测故障幅值选择合适的故障检测统计量并细化,再利用基于组合最大化思想的改进重构贡献图法,确保单故障、多故障均可隔离。以高速列车双通道速度传感器为例,实验验证了所提的策略能够满足常见速度传感器故障的检测隔离需求,准确有效。 展开更多
关键词 通道速度传感器 故障检测与隔离 改进主元分析法 改进重构贡献图
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SCR-D双通道速度控制器设计
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作者 何方 李昌钧 贠世道 《零八一科技》 2004年第1期35-39,共5页
本文主要叙述一个模块化的双通道速度控制器的设计,利用磁放大器和快速可控硅及信号处理电路组成一个整体功能模块可用于组成高精度伺服控制系统。
关键词 SCR-D 通道速度控制器 伺服控制器 磁放大器 快速可控硅 信号处理
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列车运行监控装置(LKJ)速度与压力故障原因及分析 被引量:1
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作者 高超 《中小企业管理与科技》 2016年第24期214-215,共2页
列车运行监控装置(以下简称LKJ),是中国列车运行控制系统体系的组成部分,是用于防止列车冒进信号、运行超速事故和辅助机车司机提高操纵能力的重要行车设备。LKJ系统设备运行的稳定程度极大关系着铁路客货运输的安全及效率。
关键词 LKJ 速度通道 压力通道 工作原理 故障分析
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一种新的空空雷达主动制导导弹抗速度波门拖引干扰方法 被引量:2
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作者 李小龙 王星 +1 位作者 李彬 程嗣怡 《电光与控制》 北大核心 2012年第2期33-36,共4页
速度波门拖引干扰是常用的导引头干扰技术,它严重影响空空雷达主动制导导弹的速度跟踪通道,导致其不能稳定跟踪目标,及时转入末制导状态,影响导弹的作战效能。为有效识别干扰,针对该类干扰信号特点,提出了一种基于EMD分解的抗速度波门... 速度波门拖引干扰是常用的导引头干扰技术,它严重影响空空雷达主动制导导弹的速度跟踪通道,导致其不能稳定跟踪目标,及时转入末制导状态,影响导弹的作战效能。为有效识别干扰,针对该类干扰信号特点,提出了一种基于EMD分解的抗速度波门拖引干扰的方法。通过对目标多普勒回波信号进行分解,滤除回波信号中的高频干扰部分,并对低频分量进行信号重构,得到消除干扰后的回波信号。仿真结果表明,该方法能较好地抑制拖引干扰。 展开更多
关键词 主动制导导弹 欺骗干扰 波门拖引 速度跟踪通道 经验模态分解方法
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基于神经网络的地铁列车速度传感器故障诊断方法 被引量:7
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作者 宋云 朱明年 《城市轨道交通研究》 北大核心 2014年第5期94-97,101,共5页
为了改善城市轨道交通列车设备安装空间和确保列车运行安全,提出一种基于径向基神经网络的双通道速度传感器在线故障检测诊断方法。通过建立双通道速度传感器神经网络故障检测模型,提出3种故障检测策略,并且对模型进行调试试验。试验结... 为了改善城市轨道交通列车设备安装空间和确保列车运行安全,提出一种基于径向基神经网络的双通道速度传感器在线故障检测诊断方法。通过建立双通道速度传感器神经网络故障检测模型,提出3种故障检测策略,并且对模型进行调试试验。试验结果表明所提出的方法能够准确检测传感器故障,为地铁列车提出一种新的故障检测方法。 展开更多
关键词 地铁列车 径向基函数 通道速度传感器 神经网络
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基于通用图形处理器的大规模Costas信号脉压处理
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作者 周斌 叶春茂 +1 位作者 李文雯 宋苗苗 《山东科学》 CAS 2012年第6期47-53,共7页
本文分析了并行Costas信号脉压方法,设计了基于"通用图形处理单元(GPGPU)"的处理模型,并基于"铺路爪"雷达参数实现了Costas信号的方案。该方案在8片Nvidia tesla C1060的异构系统上对5418个通道脉压处理耗时514.3ms... 本文分析了并行Costas信号脉压方法,设计了基于"通用图形处理单元(GPGPU)"的处理模型,并基于"铺路爪"雷达参数实现了Costas信号的方案。该方案在8片Nvidia tesla C1060的异构系统上对5418个通道脉压处理耗时514.3ms,比通用CPU处理系统速度提升574倍。研究结果对新一代异构高性能雷达信号处理系统的设计具有很好的参考意义。 展开更多
关键词 高速雷达信号处理 Costas信号 速度通道处理 通用图形处理单元
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Structure design for electron beam controlling in microwave tube with carbon nanotube cathode
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作者 赵红平 雷威 +2 位作者 张晓兵 顾伟 李晓华 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期159-163,共5页
To control the electron beam emitted from the carbon nanotube (CNT) cathode, four different electron chunnels are designed. A common basic structure used in the simulation is an insulating chunnel. When primary elec... To control the electron beam emitted from the carbon nanotube (CNT) cathode, four different electron chunnels are designed. A common basic structure used in the simulation is an insulating chunnel. When primary electrons hit the surface of the chunnel, secondary electrons are generated, which make the electron distribution at the exit hole of the chunnel more uniform. By analyzing and comparing the state of electrons emitted from the exit of chunnel among the four structures, an optimal structure is obtained. In the optimized structure, the electron distribution at the exit hole of the chunnel is more uniform and the electron beam is rather slim. Furthermore, by adding a magnetic field along the slow wave line, the electron beam can be constrained. In the optimized structure, a very small magnetic field is needed to make most of electrons pass through the slow wave line. 展开更多
关键词 carbon nanotube electron chunnel transverse velocity of electrons
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Stationarity Intervals of Time-Variant Channel in High Speed Railway Scenario 被引量:15
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作者 Chen Binghao Zhong Zhangdui Ai Bo 《China Communications》 SCIE CSCD 2012年第8期64-70,共7页
The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the... The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the channel keeps constant or has no great change, is adopted based on Zhengzfiou- Xi'an (Zhengxi) passenger dedicated line measurement with different train speeds. The stationarity interval is calculated through the definition of Local Region of Stationarity (LRS) under three train ve- locities. Furthermore, the time non-stationary characteristic of high speed pared with five standard railway channel is corn- Multiple-Input MultipleOutput (MIMO) channel models, i.e. Spatial Channel Model (SCM), extended version of SCM (SCME), Wireless World Initiative New Radio Phase II (WINNERII), International Mobile Teleconmnications-Advanced (IMT-Advanced) and WiMAX models which contain the high speed moving scenario. The stationarity interval of real channel is 9 ms in 80% of the cases, which is shorter than those of the standard models. Hence the real channel of high speed railway changes more rapidly. The stationarity intervals of standard models are different due to different modeling methods and scenario def- initions. And the compared results are instructive for wireless system design in high speed railway. 展开更多
关键词 channel characterization time-variantcharacteristic stationarity interval high speed railway standard MIMO channel model
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Characteristics of a Drainage Channel with Staggered Indented Sills for Controlling Debris Flows 被引量:4
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作者 CHEN Xiao-qing YOU Yong +2 位作者 CHEN Jian-gang HUANG Kai LI De-ji 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1242-1252,共11页
The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, wherea... The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, whereas the fluid near the sidewall had a stop-start movement pattern; the viscous debris flow exhibited a stable structure between the indented sills. The experimental results indicate that the mean velocity of the debris flow increased with increasing channel gradients, and the debris flow velocity was slightly affected by the angle of the sills. The average velocity of the non-viscous debris flow increased in the range of(0.5–1.5) interval between the indented sills, whereas the average velocity of the viscous debris flow increased initially and then decreased in the range of(0.75–1.25) interval between the indented sills. The depth of the non-viscous debris flow tended to gradually increase as the channel gradients increased, whereas the depth of the viscous debris flow gradually decreased as the channel gradients increased. When the discharge of the debris flow was constant, the angle and the interval between the indented sills had a slight effect on the depth of the viscous debris flow, whereas the depth of the non-viscous debris flow exhibited a different trend, as the sill angles and intervals were varied. 展开更多
关键词 Debris flow Drainage channel Staggered indented sill Wenchuan earthquake
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Concept Paper: Developing Pavement Structural Deterioration Curves
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作者 Gregory Kelly Gary Chai +2 位作者 Sittampalam Manoharan Deborah Delaney Sanaul Chowdhury 《Journal of Civil Engineering and Architecture》 2018年第7期518-526,共9页
A SN (structural number) can be calculated for a road pavement from the properties and thicknesses of the surface, basecourse, sub-base and subgrade. Historically, the cost of collecting structural data has been ver... A SN (structural number) can be calculated for a road pavement from the properties and thicknesses of the surface, basecourse, sub-base and subgrade. Historically, the cost of collecting structural data has been very high. Data was initially collected using Benkelman Beams and now by FWD (falling weight deflectometer). The structural strength of pavements weakens over time due to environmental and traffic loading factors but due to a lack of data, no structural deterioration curve for pavements has been implemented in a PMS (pavement management system). IRI (international roughness index) is a measure of the road longitudinal profile and has been used as a proxy for a pavement’s structural integrity. This paper offers two conceptual methods to develop PSDC (pavement structural deterioration curves). Firstly, structural data are grouped in sets by design ESA (equivalent standard axles). An ISN (“initial” SN), SNI (intermediate SN) and a TSN (terminal SN), are used to develop the curves. Using FWD data, the ISN is the SN after the pavement is rehabilitated (Financial Accounting “Modern Equivalent”). Intermediate SNIs, are SNs other than the ISN and TSN. The TSN was defined as the SN of the pavement when it was approved for pavement rehabilitation. The second method is to use TSD (traffic speed deflectometer) data. The road network already divided into road blocks, is grouped by traffic loading. For each traffic loading group, road blocks that have had a recent pavement rehabilitation, are used to calculate the ISN and those planned for pavement rehabilitation to calculate the TSN. The remaining SNs are used to complete the age-based or if available, historical traffic loading-based SNIs. 展开更多
关键词 CONCEPTUAL pavement structural number pavement structural deterioration curve pavement management system.
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Cellular Automaton Models of Highway Traffic Flow Considering Lane-Control and Speed-Control 被引量:1
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作者 钱勇生 李文俊 +3 位作者 曾俊伟 王敏 杜加伟 广晓平 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期785-790,共6页
As two kinds of management modes of highway tramc control, lane-control, and speed-control produce different effect under different conditions. In this paper, traffic flow cellular automaton models for four-lane highw... As two kinds of management modes of highway tramc control, lane-control, and speed-control produce different effect under different conditions. In this paper, traffic flow cellular automaton models for four-lane highway system with two opposing directions under the above two modes are established considering car and truck mixed running. Through computer numerical simulating, the fundamental diagrams with different parameters are obtained, and after the analysis of density-flux diagrams, the variation discipline of flux with traffic density under different control models is gained. The results indicate that, compared with lane-control, utilization ratio of road can be further improved with speed-control when the truck number increases. The research result is of great significance for reasonable providing theoretical guidance for highway traffic control. 展开更多
关键词 HIGHWAY cellular automaton model mixed traffic flow lane-control speed-control
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Jam Formation of Traffic Flow in Harbor Tunnel
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作者 何红弟 卢伟真 董力耘 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第12期1140-1144,共5页
This paper reports a study concerning occurrence and growth of traffic jam in a harbor tunnel. The single-lane with three sections (downgrade, fiat, and upgrade) is taken into account and they are characterized with... This paper reports a study concerning occurrence and growth of traffic jam in a harbor tunnel. The single-lane with three sections (downgrade, fiat, and upgrade) is taken into account and they are characterized with different velocity limit. At the low density, the traffic current increases linearly with density and saturates at some values of immediately density. As the density increases, the traffic jam appears firstly before the upgrade section and then extends to the downgrade section. Additionally, the relationships of the velocity and headway against position in different densities are obta/ned from simulation. These results clearly clarify where and when the traffic jam appears. Finally, the critical densities are derived via the theoretical analysis before and after the discontinuous fronts and the theoretical results are consistent with the critical values of simulation results. 展开更多
关键词 traffic jam critical densities harbor tunnel SLOPE
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Analytical Models for Velocity Distributions in Compound Channels with Emerged and Submerged Vegetated Floodplains
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作者 ZHANG Mingwu JIANG Chunbo +3 位作者 HUANG Heqing Gerald Charles NANSON CHEN Zhengbing YAO Wenyi 《Chinese Geographical Science》 SCIE CSCD 2017年第4期577-588,共12页
The lateral distributions of depth-averaged velocity in open compound channels with emerged and submerged vegetated floodplains were analyzed based on the analytical solution of the depth-integrated Reynolds-Averaged ... The lateral distributions of depth-averaged velocity in open compound channels with emerged and submerged vegetated floodplains were analyzed based on the analytical solution of the depth-integrated Reynolds-Averaged Navier-Stokes equation with a term to account for the effects of vegetation.The three cases considered for open channels were two-stage rectangular channel with emerged vegetated floodplain,rectangular channel with submerged vegetated corner,and two-stage rectangular channel with submerged vegetated floodplain,respectively.To predict the depth-averaged velocity with submerged vegetated floodplains,we proposed a new method based on a two-layer approach where flow above and through the vegetation layer was described separately.Moreover,further experiments in the two-stage rectangular channel with submerged vegetated floodplain were carried out to verify the results.The analytical solutions of the cases indicated that the corresponding analytical depth-averaged velocity distributions agree well with the simulated and experimental prediction.The analytical solutions of the cases with theoretical foundation and without programming calculation were reasonable and applicable,which were more convenient than numerical simulations.The analytical solutions provided a way for future researches to solve the problems of submerged vegetation and discontinuous phenomenon of depth-averaged velocity at the stage point for compound channels.Understanding the hydraulics of flow in compound channels with vegetated floodplains is very important for supporting the management of fluvial processes. 展开更多
关键词 compound channel velocity distribution vegetated floodplain two-stage rectangular channel analytical solution
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5.9 GHz Vehicular Channels Comparisons Between Two Traffic Status for Dense Urban Area
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作者 Fang Li Wei Chen +6 位作者 Yishui Shui Lida Xu Junyi Yul Changzhen Li Kun Yang Fuxing Chang Yi Liu 《China Communications》 SCIE CSCD 2018年第4期58-71,共14页
This study focused on differences in vehicle-to-vehicle radio channel character- istics in the same region but different traffic density and speeds at 5.9 GHz (congestion and non-congestion). The continuous measurem... This study focused on differences in vehicle-to-vehicle radio channel character- istics in the same region but different traffic density and speeds at 5.9 GHz (congestion and non-congestion). The continuous measurement campaign was conducted on a city expressway through the complex dense urban area in Wu- hart, China. Small-scale channel characteris- tics including power delay profile, amplitude fading distribution, K-factor, delay spread and Doppler shift were obtained, respectively. Spe- cifically, the cumulative distribution function of root mean square delay spreads and root mean square Doppler spreads in the non-con- gested scenario and congested scenario were all fitted well with Lognormal distribution. We also found out that different intensity of traffic and speed of vehicles have little effect on root mean square delay spreads, but have a big im- pact on root mean square Doppler spreads and level crossing rate. According to estimation outcomes, the V2V channel characteristics for urban areas in Chinese big city were differ- ent from the previous measured results under similar scenarios in Europe. Delay spread and level crossing rate in this study can provide significant references to design the wireless communication system for vehicle-to-vehicle channel. 展开更多
关键词 channel estimation vehicularchannels PDP small-scale fading Dopplerspread.
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Experimental Investigations on Fiber Motion within Rotor Spinning Unit
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作者 JIN Yuzhen LI Xiangdong +2 位作者 JIANG Shunwei CUI Jingyu ZHU Zuchao 《Journal of Thermal Science》 SCIE EI CAS CSCD 2017年第4期385-389,共5页
An experimental platform is constructed to photograph fibers' motion within rotor spinning unit, which is mainly composed of a transparent rotor and a transport channel based on the similarity theory. The fibers will... An experimental platform is constructed to photograph fibers' motion within rotor spinning unit, which is mainly composed of a transparent rotor and a transport channel based on the similarity theory. The fibers will stretch and gather into a fiber bundle in the transport channel. The velocity of fibers is increasing along the inlet to the outlet of the transport channel, and the fibers' maximum velocity appears at the outlet of transport channel. The straightness of the fiber bundle is related to the convergence degree of the transport channel, and the greater the convergence degree is, the straighter the fiber bundle stretches. The results will provide a useful insight to the yam-forming mechanism of rotor spinning. 展开更多
关键词 rotor spinning unit rotor cup transport channel fibers motion experimental investigations
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A DLM/FD/IB Method for Simulating Compound Cell Interacting with Red Blood Cells in a Microchannel
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作者 Shihai ZHAO Yao YU +1 位作者 Tsorng-Whay PAN Roland GLOWINSKI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2018年第3期535-552,共18页
In this article, a computational model and related methodologies have been tested for simulating the motion of a malaria infected red blood cell (iRBC for short) in Poiseuille flow at low Reynolds numbers. Besides t... In this article, a computational model and related methodologies have been tested for simulating the motion of a malaria infected red blood cell (iRBC for short) in Poiseuille flow at low Reynolds numbers. Besides the deformability of the red blood cell membrane, the migration of a neutrally buoyant particle (used to model the malaria parasite inside the membrane) is another factor to determine the iRBC motion. Typically an iRBC oscillates in a Poiseuille flow due to the competition between these two factors. The interaction of an iRBC and several RBCs in a narrow channel shows that, at lower flow speed, the iRBC can be easily pushed toward the wall and stay there to block the channel. But, at higher flow speed, RBCs and iRBC stay in the central region of the channel since their migrations axe dominated by the motion of the RBC membrane. 展开更多
关键词 Compound cell Red blood cells Elastic spring model Fictitious domainmethod Immersed boundary method MICROCHANNEL
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Transport of Cu-H2O nanofluid through a channel with wavy walls under velocity slip and connective boundary conditions
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作者 F. M. Abbasi T. Hayat A. Alsaedi 《International Journal of Biomathematics》 2016年第2期85-103,共19页
Present study examines the mixed convective peristaltic transport of Cu-H2O nanofluid with velocity slip and convective boundary conditions. Analysis is performed using the two-phase model of the nanofluid. Viscous di... Present study examines the mixed convective peristaltic transport of Cu-H2O nanofluid with velocity slip and convective boundary conditions. Analysis is performed using the two-phase model of the nanofluid. Viscous dissipation and heat generation/absorption effects are also taken into account. Problem is formulated using the long wavelength and low Reynolds number approach. Numerical solutions for the pressure rise per wavelength, pressure gradient, axial velocity, temperature and heat transfer rate at the boundaxy are obtained and studied through graphs. Results show that the area of peristaltic pumping decreases with an increase in the nanoparticles volume fraction. Increase in the velocity slip parameter shows an increase of the pressure gradient in the occluded part of the channel. Further, addition of copper nanoparticles reduces both the axial velocity and temperature of the base fluid. Temperature of the nanofluid also decreases sufficiently for an increase in the value of Blot number. 展开更多
关键词 PERISTALSIS slip effects convective boundary conditions Cu-H2O nanofluid wavy walls.
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