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观测域求积分卡尔曼滤波的机载无源定位算法 被引量:6
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作者 刘学 焦淑红 司锡才 《西安交通大学学报》 EI CAS CSCD 北大核心 2011年第5期137-142,共6页
针对机载无源定位系统中存在滤波稳定性差、收敛速度慢、定位精度差等问题,提出一种观测域平方根求积分卡尔曼滤波算法.新算法兼顾了观测域滤波和平方根求积分卡尔曼滤波的优点,将状态矢量中的各个分量自动解耦,分离了可观测项和不可观... 针对机载无源定位系统中存在滤波稳定性差、收敛速度慢、定位精度差等问题,提出一种观测域平方根求积分卡尔曼滤波算法.新算法兼顾了观测域滤波和平方根求积分卡尔曼滤波的优点,将状态矢量中的各个分量自动解耦,分离了可观测项和不可观测项;通过采用Gaussian-Hermit积分规则提高了非线性变换后随机变量参数的估计精度,有效地降低了状态域与观测域之间转换时存在的高阶误差;使用误差协方差阵的平方根代替协方差阵参与递推滤波,在保证数值稳定性的同时提高了算法的运行效率.计算机仿真表明:新算法提高了滤波稳定性、收敛速度和定位精度. 展开更多
关键词 机载无源定位 观测域滤波 求积分卡尔曼滤波器 Gaussian-Hermit积分规则
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基于观测域平方根UKF的机载无源定位算法
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作者 刘学 焦淑红 《弹箭与制导学报》 CSCD 北大核心 2011年第1期193-196,共4页
针对机载无源定位存在滤波稳定性差、收敛速度慢、定位精度低等问题,提出一种观测域平方根UKF滤波算法,新算法充分利用了观测域滤波的自动解耦功能和平方根UKF良好的数值稳定性及非线性滤波能力,并通过最小偏度单形采样的UT变换减少了... 针对机载无源定位存在滤波稳定性差、收敛速度慢、定位精度低等问题,提出一种观测域平方根UKF滤波算法,新算法充分利用了观测域滤波的自动解耦功能和平方根UKF良好的数值稳定性及非线性滤波能力,并通过最小偏度单形采样的UT变换减少了算法在状态域与观测域之间转换时存在的舍入误差,同时也提高了算法的运行效率。仿真结果表明新算法提高了滤波稳定性、收敛速度和定位精度。 展开更多
关键词 机载无源定位 观测域滤波 平方根UKF算法 最小偏度单形采样
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一种位域比例观测器及其在火电机组过程控制中的应用
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作者 李军 黄卫剑 +3 位作者 陈锦攀 石上瑶 陈鹏云 梁爽 《广东电力》 2023年第2期135-142,共8页
随着新型绿色能源装机容量的快速增长,电网亟需快速增加深度调峰、快速调频能力。现有火电机组是实现电网快速增加深度调峰、快速调频能力的主力军。工程最速控制器(engineering fastest controller,EFC)奠定了现有火电机组实现电网快... 随着新型绿色能源装机容量的快速增长,电网亟需快速增加深度调峰、快速调频能力。现有火电机组是实现电网快速增加深度调峰、快速调频能力的主力军。工程最速控制器(engineering fastest controller,EFC)奠定了现有火电机组实现电网快速增加深度调峰、快速调频能力的良好基础,但在其应用过程中发现,重要过程参数大幅超标的风险始终无法避免。针对此,运用一位式控制技术发明一种位域比例观测器(position zone proportion observer,PZPO),并结合EFC应用,进一步提升EFC的综合控制性能,有效降低了重要过程参数大幅超标的风险。仿真实验验证了PZPO的应用效果,典型工程应用案例证明PZPO进一步提升了火电机组深度调峰、快速调频能力,有助于新型绿色能源的消纳和快速发展。 展开更多
关键词 新型电力系统 火电机组 过程参数 工程最速控制器 比例观测 位式控制
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顾及相机可观测域的地理场景多相机视频浓缩 被引量:2
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作者 王飞跃 解愉嘉 毛波 《武汉大学学报(信息科学版)》 EI CAS CSCD 北大核心 2021年第4期595-600,共6页
现有的视频浓缩方法无法有效表达视频对象在多相机地理场景中的全局运动情况。针对该问题,提出了顾及相机可观测域的地理场景多相机视频浓缩方法。首先基于视频空间化处理,进行地理场景中相机可观测域分析;其次通过多相机视频对象的数... 现有的视频浓缩方法无法有效表达视频对象在多相机地理场景中的全局运动情况。针对该问题,提出了顾及相机可观测域的地理场景多相机视频浓缩方法。首先基于视频空间化处理,进行地理场景中相机可观测域分析;其次通过多相机视频对象的数据组织,优选相机可观测组集合,获得虚拟视点;最终实现场景中多相机视频浓缩。实验结果表明,所提方法不仅能够表现视频对象在多个相机镜头中的全局运动情况,而且相比于虚拟场景中的单相机视频浓缩具有更高的时间压缩率。 展开更多
关键词 多相机视频浓缩 地理场景 相机可观测域
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基于域方法的饱和励磁控制器设计
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作者 李江 李军徽 +2 位作者 王利猛 李国庆 董晓亮 《中国电机工程学报》 EI CSCD 北大核心 2012年第16期85-91,共7页
同步发电机励磁系统受到物理结构的限制,励磁电压的输出含有饱和环节,其具有非线性特征。基于域方法,提出饱和励磁控制器的设计思路。首先,利用扩张状态观测器,对模型内部不确定性和外部扰动进行动态补偿,实现非线性系统的反馈线性化;然... 同步发电机励磁系统受到物理结构的限制,励磁电压的输出含有饱和环节,其具有非线性特征。基于域方法,提出饱和励磁控制器的设计思路。首先,利用扩张状态观测器,对模型内部不确定性和外部扰动进行动态补偿,实现非线性系统的反馈线性化;然后,引入饱和指示器,将含饱和环节的线性化模型转化为多面体模型,并将饱和系统的二次稳定性条件用不等式表示出来;引入初始状态域,将初始状态域含于椭球吸引域内的几何关系表示为不等式;最后,为使系统在给定初始状态域、吸引域和线性矩阵不等式区域内满足二次稳定条件,将控制器设计问题转化为双线性矩阵不等式的求解问题。算例研究表明:设计的控制器是有效的,具有优良的控制性能。 展开更多
关键词 饱和励磁控制器 扩张状态观测器:吸引 初始状态 线性矩阵不等式区
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匀速或匀加速运动目标的位置预测问题的分析 被引量:5
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作者 王敏 吴向军 王书基 《船舶工程》 CSCD 北大核心 1995年第3期40-48,3,共9页
本文提出了一种计算匀速或匀加速运动目标的空间位置分析预测的新理论。这种分析预测新理论与传统理论在预测方法的区别是改变了传统的观测方程和优化法则,增加了模拟方程阶的识别技术。它与传统理论在实际应用上的差别是对作出结论所... 本文提出了一种计算匀速或匀加速运动目标的空间位置分析预测的新理论。这种分析预测新理论与传统理论在预测方法的区别是改变了传统的观测方程和优化法则,增加了模拟方程阶的识别技术。它与传统理论在实际应用上的差别是对作出结论所需要的数据量没有要求,提供的运动目标位置预测值是有直接误差估计的,可提供一组满足不同时间需求的预测计算方法等。 展开更多
关键词 观测误差 观测域 预测 估计 位置 雷达
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基于虚拟嵌入块和量化器原点抖动的YASS改进算法 被引量:2
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作者 马丽红 李晓 吕先明 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第1期38-46,共9页
为了提高YASS算法的隐写安全性,提出一种基于灵活次序的虚拟嵌入块和量化器原点随机抖动的YASS改进算法———VHD-YASS算法.为了增加嵌入位置的随机性,该改进算法在每个载体块内随机选取一个不规则区域,重新生成一个虚拟的8×8小块... 为了提高YASS算法的隐写安全性,提出一种基于灵活次序的虚拟嵌入块和量化器原点随机抖动的YASS改进算法———VHD-YASS算法.为了增加嵌入位置的随机性,该改进算法在每个载体块内随机选取一个不规则区域,重新生成一个虚拟的8×8小块来取代传统YASS算法中规则的8×8嵌入块,用于消息的嵌入;然后,通过密钥控制量化索引调制(QIM)中奇/偶量化器的原点偏移,消除QIM量化步长较大时消息嵌入造成的DCT系数聚集效应.将文中改进算法与传统YASS算法和两种不同的改进YASS算法进行了对比实验,结果表明:在同一嵌入容量下,文中改进算法的检测概率最高为0.614,而传统YASS算法的检测概率最高为0.983.从抗隐写分析能力、可视性及算法复杂度方面综合分析可知,文中算法是一种有效的隐写算法. 展开更多
关键词 YASS算法 虚拟嵌入块 量化器 原点抖动 观测域 隐写分析
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一种加速度干扰下的稳定被动定位跟踪算法
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作者 刘洋 冯道旺 郭福成 《航天电子对抗》 2011年第5期47-49,共3页
在研究一种具有误差自动解耦的观测域滤波的目标跟踪算法和自适应渐消EKF算法的基础上,提出一种匀速运动模型下,基于观测域的自适应目标跟踪算法。使用实测GPS导航数据进行数字仿真,结果表明:观测域的自适应目标跟踪算法在加速度扰动下... 在研究一种具有误差自动解耦的观测域滤波的目标跟踪算法和自适应渐消EKF算法的基础上,提出一种匀速运动模型下,基于观测域的自适应目标跟踪算法。使用实测GPS导航数据进行数字仿真,结果表明:观测域的自适应目标跟踪算法在加速度扰动下,稳定性优于观测域滤波算法。 展开更多
关键词 加速度扰动 观测域 自适应渐消滤波
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基于一种改进滤波算法的双天线单站无源定位技术研究
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作者 郭静 梁炳峰 +2 位作者 刘平原 汪玥 贺杨婷 《遥测遥控》 2017年第5期66-73,共8页
研究移动单站利用双天线对固定辐射源进行无源定位的技术。首先介绍联合相位差变化率、多普勒频率变化率和角度信息测距原理,考虑到双天线测角精度较低,提出一种观测域平方根稀疏网格积分卡尔曼滤波器(MSSRSGQKF)。这种滤波算法收敛速... 研究移动单站利用双天线对固定辐射源进行无源定位的技术。首先介绍联合相位差变化率、多普勒频率变化率和角度信息测距原理,考虑到双天线测角精度较低,提出一种观测域平方根稀疏网格积分卡尔曼滤波器(MSSRSGQKF)。这种滤波算法收敛速度快、精度高,并通过稀疏网格取点降低了算法计算量。仿真对比了基于MSSRSGQKF的定位方法与扇形网格搜索定位方法及粒子滤波定位方法的性能,证明基于MSSRSGQKF的定位算法收敛速度更快,收敛精度更高,计算量较小,整体性能更优。 展开更多
关键词 无源定位 稀疏网格 观测域滤波
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Performance of Regional Integrated Environment Modeling System (RIEMS) in the Simulation of Surface Air Temperature over East Asia 被引量:4
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作者 Zhao De-Ming 《Atmospheric and Oceanic Science Letters》 2012年第2期145-150,共6页
Regional climate models (RCMs) have the potential for more detailed surface characteristic and mesoscale modeling results than general circulation models (GCMs).These advantages have drawn significant focus on RCM dev... Regional climate models (RCMs) have the potential for more detailed surface characteristic and mesoscale modeling results than general circulation models (GCMs).These advantages have drawn significant focus on RCM development in East Asia.The Regional Integrated Environment Modeling System,version 2.0 (RIEMS2.0),has been developed from an earlier RCM,RIEMS1.0,by the Key Laboratory of Regional ClimateEnvironment for Temperate East Asia (RCE-TEA) and Nanjing University.A numerical experiment covering 1979 to 2008 (simulation duration from 1 January 1978 to 31 December 2008) with a 50-km spatial resolution was performed to test the ability of RIEMS2.0 to simulate long-term climate and climate changes in East Asia and to provide a basis for further development and applications.The simulated surface air temperature (SAT) was compared with observed meteorological data.The results show that RIEMS2.0 simulation reproduced the SAT spatial distribution in East Asia but that it was underestimated.The simulated 30-year averaged SAT was approximately 2.0°C lower than the observed SAT.The annual and interannual variations in the averaged SAT and their anomalies were both well reproduced in the model.A further analysis of three sub-regions representing different longitudinal ranges showed that there is a good correlation and consistency between the simulated results and the observed data.The annual variations,interannual variations for the averaged SAT,and the anomalies in the three sub-regions were also captured well by the model.In summary,RIEMS2.0 shows stability and does well both in simulating the long-term SAT in East Asia and in expressing sub-regional characteristics. 展开更多
关键词 RIEMS2.0 surface air temperature CLIMATE simulation ability
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Test and evaluation of a moored microstructure recorder
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作者 田川 王树新 +2 位作者 管守德 杨庆轩 徐霄阳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第1期201-209,共9页
A new moored microstructure recorder(MMR) is designed, developed, tested, and evaluated. The MMR directly measures the high-frequency shear of velocity fl uctuations, with which we can estimate the dissipation rate of... A new moored microstructure recorder(MMR) is designed, developed, tested, and evaluated. The MMR directly measures the high-frequency shear of velocity fl uctuations, with which we can estimate the dissipation rate of turbulent kinetic energy. We summarize and discuss methods for estimating the turbulent kinetic energy dissipation rate. Instrument body vibrations contaminate the shear signal in an ocean fi eld experiment, and a compensating correction successfully removes this contamination. In both tank test and ocean fi eld experiment, the dissipation rate measured with the MMR agreed well with that measured using other instruments. 展开更多
关键词 moored microstructure recorder (MMR) dissipation rate turbulent kinetic energy shear ofvelocity fluctuations compensating correction
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The dynamic analysis of natural environment change of nuclear test field in Lop Nur region of China
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作者 Hu Dongsheng Pang Xilei +5 位作者 Zhang Huajing Xu Bing Yu Xuefeng Tian Xinhong An Zhisheng Zhang Guowei 《Engineering Sciences》 EI 2008年第3期37-44,共8页
Using earth satellite observation means, remote sensing information distilled technique and regional research production, we have roundly analyzed and made an integrated evaluation about the Lop Nur nuclear test field... Using earth satellite observation means, remote sensing information distilled technique and regional research production, we have roundly analyzed and made an integrated evaluation about the Lop Nur nuclear test field in western China. This product reveals the rarely-known nuke explosion effect and response events of geology conditions. It also offers us legible and practical first-hand materials about human extreme effects, important engineering environment and intimidating influence process. By excavating and appraising the materials gradually on the natural environment factors changing in the test field through macroscopic elimination and typical filtration, it can supply basic scientific data for security of national nuclear usage, appraising the nuclear environment synthetically and developing nuclear strategy expediently. 展开更多
关键词 earth's satellite observation the nuclear test field the nuke explosion effect and the response process of geological environment comprehensive evaluation of natural resource environment Lop Nut region of China
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Climatology of Guinea: Study of Climate Variability in N'zerekore
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作者 Rene Tato Loua Maoro Beavogui +3 位作者 Hassan Bencherif Alpha Boubacar Barry Zoumana Bamba Christine Amory Mazodier 《Journal of Agricultural Science and Technology(A)》 2017年第4期215-233,共19页
N'zerekore is a geographical region of Guinea, which houses a weather observatory located at longitude 8.8°, latitude 7.7° and altitude 475 m. This region is of major socio-economic interest for the Country... N'zerekore is a geographical region of Guinea, which houses a weather observatory located at longitude 8.8°, latitude 7.7° and altitude 475 m. This region is of major socio-economic interest for the Country. The climatological study of this region shows the variability of each parameter. The objective of this study was to analyze meteorological parameters trends and to assess the space-time evolution of some agro-climatic risks related to the main trends observed in the meteorological parameters regime of this region. In this study, programming tools were used for processing and analyzing meteorological parameters data, including temperatures, rains, wind, evaporation and storms measured in this observatory from 1931 to 2014. The interannual, annual and daily variations of these parameters were obtained, as well as temperature, precipitation anomalies and agroclimatic indexes trends. The analyzing of these variations explained that September is the rainiest months, and the year 1932, 1957 and 1970 are normal, rainy and dry year, respectively. The evaporation increased since 1971 from January to March and November to December. A positive temperature anomaly was observed since 1973 with the maximum 26-33 ℃ and the minimum 16-21 ℃. A dominant westerly wind with a speed of 2.6 m/s was determined. Agro-climatic parameters in N'zerekore have high variability. From 1931 to 2014, three major periods can be distinguished: a wet period from 1931 to 1977, a dry period from 1978 to 1994 and rainfall variability from 1995 to 2014. The trend of these parameters explains the impact of climate change in this part of the world. This is exacerbated by human activity (deforestation), thus mitigation measures are necessary. It would be useful to extend this study throughout the country. 展开更多
关键词 Climate change N'zerekore agroclimatic index.
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Study on Precursory Features of the Lop M_S6. 0 Earthquake Based on GPS Continuous Observation Data and Mobile Gravity Data
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作者 Zhu Zhiguo Li Guirong 《Earthquake Research in China》 CSCD 2015年第3期386-393,共8页
Through calculating and analyzing of GPS continuous observation data and mobile gravity data,the study results from the data are as follows.( 1) The different movement rate of the fault ends provides conditions for st... Through calculating and analyzing of GPS continuous observation data and mobile gravity data,the study results from the data are as follows.( 1) The different movement rate of the fault ends provides conditions for stress accumulation.( 2) The high value zone of gravity anomaly appeared in the monitoring area before the earthquake,and gravity variation contour lines are parallel to the strike of fault; and the process of enhancingweakening-enhancing appeared in the regional gravity field before earthquake. 展开更多
关键词 Lop earthquake GPS Gravity field Precursory features
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Comparison Research on the Records of Strong-motion Seismographs and Seismographs at the Same Station
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作者 Liang Yongduo 《Earthquake Research in China》 CSCD 2015年第3期412-422,共11页
This paper uses Jin Xing( 2004,2005) and Ma Qiang's( 2003) real-time time-domain methods to simulate and compare both the broadband strong motion acceleration and velocity records measured at the same stations in ... This paper uses Jin Xing( 2004,2005) and Ma Qiang's( 2003) real-time time-domain methods to simulate and compare both the broadband strong motion acceleration and velocity records measured at the same stations in the Liaoning Telemetered Digital Seismic Network. The results show that we can get actual velocity and displacement time histories by simulating broadband acceleration records. The acceleration and displacement time histories also may be obtained by simulating broadband velocity records. This indicates that strong motion observations and seismometer observations can be substituted for each other in a certain range. 展开更多
关键词 Acceleration records Velocity records Simulation
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Solution of Inverse Problem on Distributed Generation Using Complex-Valued Network Inversion
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作者 Takehiko Ogawa Kyosuke Nakamura 《Journal of Mechanics Engineering and Automation》 2011年第6期436-444,共9页
Solutions of inverse problems are required in various fields of science and engineering. The concept of network inversion has been studied as a neural-network-based solution to inverse problems. In general, inverse pr... Solutions of inverse problems are required in various fields of science and engineering. The concept of network inversion has been studied as a neural-network-based solution to inverse problems. In general, inverse problems are not limited to a real-valued area. Recently, complex-valued neural networks have been actively studied in the field of neural networks. As an extension of network inversion to complex numbers, a complex-valued network inversion has been proposed. Moreover, inverse problems for estimating the parameters of distributed generation systems such as distributed energy plants or smart grids from observed electric circuit data have been studied in the field of natural energy. These emphasize the need to handle complex numbers in an alternating current (AC) circuit. In this paper, the authors propose an application of the complex-valued network inversion to the inverse estimation of a distributed generation. Further, the authors confirm the effectiveness of the complex-valued network inversion on the basis of simulation results. 展开更多
关键词 Neural networks network inversion complex numbers inverse problems distributed generation
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Comparison Study Between Observation and Simulation for Sea Fog over the Yellow Sea in May 2009
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作者 FU Dan WANG Shuai +2 位作者 CHEN Delin PANG Huaji LI Pengyuan 《Journal of Ocean University of China》 SCIE CAS 2012年第3期290-300,共11页
In this paper, almost all available observational data and the latest 6.0 version of Regional Atmospheric Modeling System (RAMS) model were employed to investigate a heavy sea fog event occurring over the Yellow Sea f... In this paper, almost all available observational data and the latest 6.0 version of Regional Atmospheric Modeling System (RAMS) model were employed to investigate a heavy sea fog event occurring over the Yellow Sea from 2 to 5 May 2009. The evolutionary process of this event was documented by using Multifunctional Transport Satellites-1 (MTSAT-1) visible satellite imagery. The synoptic situation, sounding profiles at two selected stations were analyzed. The difference between the air temperature and sea surface temperature during the sea fog event over the entire sea region was also analyzed. In order to better understand this event, an RAMS modeling with a 15 km×15 km resolution was performed. The model successfully reproduced the main characteristics of this sea fog event. The simulated height of fog top and the area of lower atmospheric visibility derived from the RAMS modeling results showed good agreement with the sea fog area identified from the satellite imagery. Examinations of both observational data and RAMS modeling results suggested that advection cooling seemed to play an important role in the formation of this sea fog event. 展开更多
关键词 sea fog the Yellow Sea observational analysis numerical modeling
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Construction of a Comprehensive Observation Network for Natural-Resource Elements in Heihe River Basin,NW China
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作者 PEI Xiaolong HAN Xiaolong +4 位作者 YANG Hanwen GAO Tiansheng ZHANG Chun GONG Lun WANG Jiangyulong 《Journal of Resources and Ecology》 CSCD 2022年第5期946-954,共9页
The construction of a comprehensive observation platform for natural-resource elements would provide data support for studies of dynamic changes in various natural resources,and could serve the needs of natural-resour... The construction of a comprehensive observation platform for natural-resource elements would provide data support for studies of dynamic changes in various natural resources,and could serve the needs of natural-resource management and the construction of ecological civilization during a period of global change.As the second-largest inland river basin in NW China,the Heihe River Basin(HRB)lies in the central part of the Silk Road Economic Belt,consequently,pilot studies of resource management in the basin are urgently needed.This paper describes the construction of a comprehensive natural-resource elements observation network in the HRB to meet requirements for natural-resource management,based on natural-resource and Earth-system science.Based on current observations and research,thirteen observation stations were established in different river basins through integration with existing stations,reconstruction and upgrading,and new construction.The main types of land-surface resources in the HRB(grassland,forests,rivers,lakes,deserts,wetlands,and farmland)were included in the observation network constructed for the monitoring of natural-resource elements.Long-term,continuous,and stable observation can yield key data concerning coupling processes,trends of change,and rates of change in natural resources.This is of great significance in improving cognitive ability,scientific management,and strategic decision-making regarding natural resources in the HRB,and can provide a reference paradigm for the observation of and research into natural resources in other basins. 展开更多
关键词 Heihe River Basin natural resources basin observing system observation stations comprehensive observation network
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