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APPLICATION AND IMPLEMENTATION OF REAL-TIME IMAGE ZOOMING WITH THE WALSH TECHNIQUE
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作者 江洁 郁道银 《Transactions of Tianjin University》 EI CAS 2001年第4期229-232,共4页
Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.Th... Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.The quality of the image is very good. 展开更多
关键词 image zooming two dimensional superimposure filter field programmable gate array (FPGA)
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A Method for Rapidly Determining the Optimal Distribution Locations of GNSS Stations for Orbit and ERP Measurement Based on Map Grid Zooming and Genetic Algorithm 被引量:3
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作者 Qianxin Wang Chao Hu Ya Mao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第12期509-525,共17页
Designing the optimal distribution of Global Navigation Satellite System(GNSS)ground stations is crucial for determining the satellite orbit,satellite clock and Earth Rotation Parameters(ERP)at a desired precision usi... Designing the optimal distribution of Global Navigation Satellite System(GNSS)ground stations is crucial for determining the satellite orbit,satellite clock and Earth Rotation Parameters(ERP)at a desired precision using a limited number of stations.In this work,a new criterion for the optimal GNSS station distribution for orbit and ERP determination is proposed,named the minimum Orbit and ERP Dilution of Precision Factor(OEDOP)criterion.To quickly identify the specific station locations for the optimal station distribution on a map,a method for the rapid determination of the selected station locations is developed,which is based on the map grid zooming and heuristic technique.Using the minimum OEDOP criterion and the proposed method for the rapid determination of optimal station locations,an optimal or near-optimal station distribution scheme for 17 newly built BeiDou Navigation Satellite System(BDS)global tracking stations is suggested.To verify the proposed criterion and method,real GNSS data are processed.The results show that the minimum OEDOP criterion is valid,as the smaller the value of OEDOP,the better the precision of the satellite orbit and ERP determination.Relative to the exhaustive method,the proposed method significantly improves the computational efficiency of the optimal station location determination.In the case of 3 newly built stations,the computational efficiency of the proposed method is 35 times greater than that of the exhaustive method.As the number of stations increases,the improvement in the computational efficiency becomes increasingly obvious. 展开更多
关键词 Global Navigation Satellite System(GNSS) optimal distribution of station network MAP GRID zooming genetic algorithm.
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Zooming算法在磁极优化设计中的应用
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作者 赖豪杰 李光友 《电机技术》 2005年第3期28-31,共4页
把一种新型全局优化算法—Zooming算法引进到电机优化设计中。首先介绍Zooming算法的基本原理,然后以该算法对永磁起动机进行磁极优化设计,取得较为满意的结果。
关键词 zooming算法 全局优化 永磁起动机 全局优化算法 优化设计 磁极 应用 永磁起动机 基本原理 电机
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Adaptive Image Zooming Algorithm Combining Total Variation Minimization and a Second-order Functional
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作者 王燕燕 高冉 顾聪 《Chinese Quarterly Journal of Mathematics》 2016年第4期435-440,共6页
An image zooming algorithm by using partial differential equations(PDEs) is proposed here. It combines the second-order PDE with a fourth-order PDE. The combined algorithm is able to preserve edges and at the same tim... An image zooming algorithm by using partial differential equations(PDEs) is proposed here. It combines the second-order PDE with a fourth-order PDE. The combined algorithm is able to preserve edges and at the same time avoid the blurry effect in smooth regions. An adaptive function is used to combine the two PDEs. Numerical experiments illustrate advantages of the proposed model. 展开更多
关键词 adaptive image zooming total variation PDES
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Image zooming via surface fitting based on edge constraint
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作者 GUO Yingying ZHANG Caiming +2 位作者 LI Weitao ZHOU Yuanfeng WANG Min 《Computer Aided Drafting,Design and Manufacturing》 2013年第1期1-6,共6页
In this paper we present a new image zooming algorithm based on surface fitting with edge constraint. In surface fitting,we consider not only the relationship of corresponding pixels between the original image and the... In this paper we present a new image zooming algorithm based on surface fitting with edge constraint. In surface fitting,we consider not only the relationship of corresponding pixels between the original image and the enlarged image, but also the neighbor pixels in the enlarged image according to the local structure of original image. Furthermore, during surface fitting, more interpolation constraints are used in the new algorithm for improving the precision of the super sampling pixels. The experimental results show that the new method outperforms the previous methods which based on surface fitting. 展开更多
关键词 image zooming surface fitting image edge
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Adaptive multiscale microscope with fast zooming,extended working distance,and large field of view
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作者 Yi Zheng Xin Wang +6 位作者 Zhao Jiang Jinbo Xu Rongying Yuan Youran Zhao Haoran Zhang Chao Liu Qionghua Wang 《Light(Advanced Manufacturing)》 2024年第1期60-72,共13页
The field-of-view(FOV),depth of field,and resolution of conventional microscopes are constrained by each other;therefore,a zoom function is required.Traditional zoom methods lose real-time performance and have limited... The field-of-view(FOV),depth of field,and resolution of conventional microscopes are constrained by each other;therefore,a zoom function is required.Traditional zoom methods lose real-time performance and have limited information throughput,severely limiting their application,especially in three-dimensional dynamic imaging and large-amount or large-size sample scanning.Here,an adaptive multiscale(AMS)imaging mechanism combining the benefits of liquid lenses and multiscale imaging techniques is proposed to realize the functions of fast zooming,wide working distance(WD)range and large FOV on a self-developed AMS microscope.The design principles were revealed.Moreover,a nonuniform-distortion-correction algorithm and a composite patching algorithm were designed to improve image quality.The continuous tunable magnification range of the AMS microscope is from 9×to 18×,with the corresponding FOV diameters and resolution ranging from 2.31 to 0.98 mm and from 161 to 287 line-pairs/mm,respectively.The extended WD range is 0.8 mm and the zoom response time is 38 ms.Experiments demonstrated the advantages of the proposed microscope in pathological sample scanning,thick-sample imaging,microfluidic process monitoring,and the observation of living microorganisms.The proposed microscope is the first step towards zoom multiscale imaging technology and is expected to be applied in life sciences,medical diagnosis,and industrial detection. 展开更多
关键词 MICROSCOPE Multiscale Liquid lens ZOOM
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Design and fabrication of compound varifocal lens driven by polydimethylsiloxane film elastic deformation
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作者 缪文浩 韩泽峰 +3 位作者 赵瑞 梁忠诚 寇松峰 徐荣青 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期342-346,共5页
A compound varifocal lens based on electromagnetic drive technology is designed and fabricated, where the polydimethylsiloxane(PDMS) film acts as a driving component, while the PDMS biconvex lens and the plane-concave... A compound varifocal lens based on electromagnetic drive technology is designed and fabricated, where the polydimethylsiloxane(PDMS) film acts as a driving component, while the PDMS biconvex lens and the plane-concave lens form a coaxial compound lens system. The plane-concave lens equipped with driving coils is installed directly above the PDMS lens surrounded by the annular magnet. When different currents are applied, the annular magnet moves up and down, driving the PDMS film to undergo elastic deformation, and then resulting in longitudinal movement of the PDMS lens. The position change of the PDMS lens changes the focal length of the compound lens system. To verify the feasibility and practicability of this design, a prototype of our compound lens system is fabricated in experiment. Our proposed compound lens shows that its zoom ability reaches 9.28 mm when the current ranges from -0.20 A to 0.21 A. 展开更多
关键词 compound varifocal lens PDMS film elastic deformation focal length electromagnetic force zoom ability
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基于频谱细化算法的超声多普勒流量计设计
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作者 李云飞 冯珂珂 +3 位作者 张飞 陈斌 车延超 金岩 《传感器与微系统》 CSCD 北大核心 2024年第10期79-83,共5页
流量计作为一种计量传感器设备,是水务信息化综合系统的重要组成部分,其数据精度直接影响系统计量结果。本文基于频谱细化的方法设计了高精度超声多普勒流量计,该流量计采用低功耗单片机(MCU)作为主控芯片,产生频率可配置的中高频脉冲信... 流量计作为一种计量传感器设备,是水务信息化综合系统的重要组成部分,其数据精度直接影响系统计量结果。本文基于频谱细化的方法设计了高精度超声多普勒流量计,该流量计采用低功耗单片机(MCU)作为主控芯片,产生频率可配置的中高频脉冲信号,经功率放大电路后驱动由大功率金属氧化物半导体场效应管(MOSFET)组成的超声波发射电路。设计了回波信号提取电路,实现回波信号的放大、噪声滤除、频差信号提取等功能。采用复调制ZOOM FFT频谱细化算法进行频谱分析,显著提高了频率分辨率和频移计算精度。经实验测试,在低流速(0.19 m/s)、中流速(0.5 m/s)和高流速(0.984 m/s)状态下,流量计测量误差分别为5.161%、2.248%和1.985%。 展开更多
关键词 流速测量 多普勒流量计 ZOOM FFT频谱细化 智慧水务 管理系统
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Analysis of the Influence of Sound Source Position and Electrode Placement on the Stimulation Pattern of the Cochlear Implant under Noise Conditions: Optimization of Auditory Perceptual Effects
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作者 Johannes Burkart 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第3期194-212,共19页
Background: Cochlear implants (CI) are widely used to restore hearing in people with severe to profound hearing loss. However, optimizing CI performance, especially in difficult listening environments with background ... Background: Cochlear implants (CI) are widely used to restore hearing in people with severe to profound hearing loss. However, optimizing CI performance, especially in difficult listening environments with background noise, remains a major challenge. Understanding the influence of factors such as sound source position and electrode placement on CI stimulation patterns is critical to improving auditory perception. Methods: In this study, an analysis was conducted to investigate the influence of sound source position and electrode placement on CI stimulation patterns under noisy conditions. For this purpose, a special measurement setup with a CI speech processor-microphone test box was used to simulate realistic listening scenarios and measure CI performance. Results: The results show that the effectiveness of CI noise reduction systems is influenced by factors such as the position of the sound source and electrode placement. In particular, the beamforming ultra zoom mode showed significantly better noise reduction than the omnidirectional mode, especially under real listening conditions. Furthermore, differences in electrode responses indicate individual variability in the CI user experience, highlighting the importance of personalized fitting algorithms. Conclusions: The results demonstrate the importance of considering environmental factors and individual differences when optimizing CI performance. Future research efforts should focus on the development of personalized fitting algorithms and the exploration of innovative strategies, such as the integration of artificial intelligence, to improve CI functionality in different listening environments. This study contributes to our understanding of CI stimulation patterns and lays the foundation for improving auditory perception in CI users. 展开更多
关键词 Cochlear Implants Noise Reduction Ultra Zoom Beamforming Anatomical Variations Personalized Fittings
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远程会议口译的发展及对教学的影响——以JIPM认证审核会议实践为例
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作者 王艳华 《漫科学(科学教育)》 2024年第4期173-175,共3页
远程会议口译的发展受到远程信息技术的推动,同时也在很大程度上受到会议组织者、参与者和口译员的影响。JIPM认证审核从传统口译模式向远程会议口译模式的转变,标志着远程会议口译的发展进入新阶段。这一变化不仅与会议组织者、参与者... 远程会议口译的发展受到远程信息技术的推动,同时也在很大程度上受到会议组织者、参与者和口译员的影响。JIPM认证审核从传统口译模式向远程会议口译模式的转变,标志着远程会议口译的发展进入新阶段。这一变化不仅与会议组织者、参与者和口译员的利益得失密切相关,同时还对口译教学提出了新的要求和挑战。基于此,文章以JIPM认证审核会议实践为例,探讨了远程会议口译的发展对教学的影响。 展开更多
关键词 远程会议口译 JIPM认证审核 口译教学 Zoom平台
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Online International Peer Interaction:An Exploration of Impacts on Comprehensive Competencies,Global Perspectives,and Cross-Cultural Communication Skills
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作者 Dong Wang 《Journal of Contemporary Educational Research》 2024年第7期89-94,共6页
With the increasing trend of globalization and the rapid advancement of information technology,online learning platforms such as Zoom are becoming increasingly influential in the field of education.The focus of this s... With the increasing trend of globalization and the rapid advancement of information technology,online learning platforms such as Zoom are becoming increasingly influential in the field of education.The focus of this study was the online international peer interaction based on the Zoom platform,detailing how such interaction programs are conducted and exploring in depth the specific impacts of this interaction mode on students’comprehensive competencies,global perspectives,and cross-cultural communication skills.This research not only provides new practical references for online learning and international education but also offers new research perspectives and directions for educators and researchers. 展开更多
关键词 Zoom platform International peer interaction Comprehensive competencies Global perspectives Cross-cultural communication skills
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ZFFT与Chirp-Z变换细化选带的频谱分析对比 被引量:56
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作者 丁康 潘成灏 李巍华 《振动与冲击》 EI CSCD 北大核心 2006年第6期9-12,共4页
在细化选带频谱分析中,复调制细化方法(ZFFT)和线性调频Z变换方法(Ch irp-Z变换)是常用的两种方法。通过理论分析和仿真计算,对两者在算法、特点和误差方面进行对比分析表明:对于单频率和谱线干涉不严重的多频率谐波成分,使用FFT后进行... 在细化选带频谱分析中,复调制细化方法(ZFFT)和线性调频Z变换方法(Ch irp-Z变换)是常用的两种方法。通过理论分析和仿真计算,对两者在算法、特点和误差方面进行对比分析表明:对于单频率和谱线干涉不严重的多频率谐波成分,使用FFT后进行校正,或者使用CZT细化分析,均能得到高精度的频率、幅值和相位,不必使用ZFFT;对于发生严重干涉现象的密集多频率谐波成分,ZFFT通过增大细化倍数后重采样,把干涉的各频率成分分离后进行校正可获得高精度的信号参数,但CZT只是把细化分析频带局部放大,无法消除干涉影响,提高频率分辨率也无法分离出信号的真实频率成分。通过增大采样点数,减少干涉产生的误差,CZT可以获得较高精度的信号参数,但却大大增加了运算时间。 展开更多
关键词 细化频谱分析 Zoom—FFt(zFFt) Chin-Z变换(CZT)
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基于傅里叶变换光谱技术的Zoom-FFT算法研究 被引量:6
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作者 张茗璇 高教波 +3 位作者 孟合民 范喆 郑雅卫 李俊娜 《应用光学》 CAS CSCD 北大核心 2013年第3期452-456,共5页
在分析经典的Zoom-FFT算法基础上,提出一种基于傅里叶变换光谱技术的Zoom-FFT算法,用matlab仿真常规FFT算法和Zoom-FFT算法,对不同采样步长的干涉条纹进行数据处理,通过反演出的光谱曲线图和原始光谱曲线图可以看出:采样步长小于20μm时... 在分析经典的Zoom-FFT算法基础上,提出一种基于傅里叶变换光谱技术的Zoom-FFT算法,用matlab仿真常规FFT算法和Zoom-FFT算法,对不同采样步长的干涉条纹进行数据处理,通过反演出的光谱曲线图和原始光谱曲线图可以看出:采样步长小于20μm时,FFT和Zoom-FFT算法都可以反演出光谱;而当采样步长大于20μm且小于33.3μm时,FFT算法未能反演出光谱,而Zoom-FFT算法仍然可以反演出光谱。 展开更多
关键词 傅里叶变换光谱技术 采样定理 采样步长 FFT Zoom—FFT
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STFT和Zoom-FRFT联合的多分量LFM信号参数估计方法 被引量:6
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作者 孙乐 张衡阳 +1 位作者 魏军 刘立 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第5期1034-1040,共7页
针对传统基于分数阶傅里叶变换(FRFT)的多分量线性调频信号(MLFM)参数估计方法中计算量大,估计精度低等问题,提出了一种短时傅里叶变换(STFT)和Zoom-FRFT联合的参数估计方法.首先,利用STFT得到MLFM信号的短时傅里叶域频谱图,对其进行直... 针对传统基于分数阶傅里叶变换(FRFT)的多分量线性调频信号(MLFM)参数估计方法中计算量大,估计精度低等问题,提出了一种短时傅里叶变换(STFT)和Zoom-FRFT联合的参数估计方法.首先,利用STFT得到MLFM信号的短时傅里叶域频谱图,对其进行直线检测得到各个分量参数的粗略估计.然后,利用LFM信号在FRFT域的频谱分布特征和STFT窗函数的主瓣带宽,计算得到待估计信号在FRFT域变换阶次和频谱的分析范围;最后,在Zoom-FRFT域采用优选法对各个分量进行精估计,得到精确的变换阶次和峰值位置.仿真结果表明,该方法可以有效地对MLFM信号进行参数估计,可以根据实际需要灵活选择窗函数的宽度和细化倍数,与传统方法相比,提高参数估计精度的同时大大减小了计算量. 展开更多
关键词 短时傅里叶变换 Zoom—FRFT 窗函数 主瓣带宽 最优阶次
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一种提高超声波多普勒流量计测量精度的方法 被引量:4
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作者 贾惠芹 时文娟 +1 位作者 冯旭东 党瑞荣 《仪表技术与传感器》 CSCD 北大核心 2015年第2期33-35,共3页
由于强噪声背景下的多普勒超声波回波信号属于微弱信号,传统谱分析方法对微小多普勒偏移量的测量误差较大,使得现有的超声多普勒流量计在应用范围和测量精度上受到限制,因此提出采用Zoom FFT结合卡尔曼滤波来提高多普勒流量计的测量精... 由于强噪声背景下的多普勒超声波回波信号属于微弱信号,传统谱分析方法对微小多普勒偏移量的测量误差较大,使得现有的超声多普勒流量计在应用范围和测量精度上受到限制,因此提出采用Zoom FFT结合卡尔曼滤波来提高多普勒流量计的测量精度。文中首先采用Zoom FFT来提高多普勒回波信号的频率分辨率,然后通过卡尔曼滤波器递推跟踪频率偏移值,最后在Matlab环境下实现了Zoom FFT算法和卡尔曼滤波算法。现场测试结果表明:采用Zoom FFT结合卡尔曼滤波可以提高流量测量精度。 展开更多
关键词 超声波流量计 测量精度 ZOOM FFT 卡尔曼滤波器 MATLAB
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基于Silverlight的海洋环境监测信息平台设计与实现 被引量:5
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作者 施佺 陆春龙 王恒山 《计算机应用与软件》 CSCD 2010年第12期82-85,共4页
遵循完整性、先进性和开放性的系统开发原则,系统采用VS.NET开发平台,利用微软最新的Silverlight技术以及其核心的DeepZoom图像处理技术,以电子海图为基础,设计实现了全新的海洋环境监测信息平台。该系统已成功应用于南通市海洋与渔业... 遵循完整性、先进性和开放性的系统开发原则,系统采用VS.NET开发平台,利用微软最新的Silverlight技术以及其核心的DeepZoom图像处理技术,以电子海图为基础,设计实现了全新的海洋环境监测信息平台。该系统已成功应用于南通市海洋与渔业信息系统中,实际应用表明该系统运行稳定可靠,在行业中具有较好的应用推广价值。 展开更多
关键词 SILVERLIGHT RIA 海洋环境监测 DEEP ZOOM
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“大学物理”课程在线混合式教学的改革与实践 被引量:26
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作者 刘海兰 顾牡 +2 位作者 吴天刚 倪忠强 宋志怀 《物理与工程》 2020年第4期3-11,25,共10页
为了做好新冠肺炎疫情防控期间"大学物理"课程的教学,实现"停课不停学""教学质量实质等效"的教学目标,依托同济大学云课堂(https://courses.tongji.edu.cn/)所用的ZOOM系统和在中国大学MOOC(https://www.... 为了做好新冠肺炎疫情防控期间"大学物理"课程的教学,实现"停课不停学""教学质量实质等效"的教学目标,依托同济大学云课堂(https://courses.tongji.edu.cn/)所用的ZOOM系统和在中国大学MOOC(https://www.icourse163.org/)上所建设的国家精品在线开放课程"大学物理(系列)课程",从多个教学环节开展了"大学物理"课程在线混合式教学模式的改革。经过一段时间的教学实践,取得了积极的成效。本文主要介绍我们教学团队在"大学物理"课程在线混合式教学方面的改革方案和具体做法,以利于相互启发、共同提高。 展开更多
关键词 “大学物理”课程 在线混合式教学 ZOOM视频直播 异步SPOC课程 慕课堂
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欠采样与ZFFT在移频信号检测中的应用 被引量:8
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作者 袁薇 孙景峰 樊文侠 《电子科技》 2010年第3期65-67,80,共4页
轨道移频信号检测需要具有相对较高的频率分辨率。在检测仪器内存和FFT计算长度有限制的情况下,为进一步获得较高的频率分辨率,则需对有用频段进行选频细化分析。文中将欠采样技术与ZOOM-FFT频谱细化技术相结合,用Matlab软件,对国产18... 轨道移频信号检测需要具有相对较高的频率分辨率。在检测仪器内存和FFT计算长度有限制的情况下,为进一步获得较高的频率分辨率,则需对有用频段进行选频细化分析。文中将欠采样技术与ZOOM-FFT频谱细化技术相结合,用Matlab软件,对国产18信息轨道移频信号检测算法进行仿真验证,结果表明所提出的检测算法是可行的,并为轨道电路移频信号检测仪表的设计提供了方法依据。 展开更多
关键词 移频信号 欠采样 ZOOM—FFT 频率分辨率 Matlab仿真
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毫米波雷达液位计高精度测距算法研究 被引量:6
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作者 王元恺 孙伟 许建中 《测试技术学报》 2015年第6期529-533,共5页
本文基于毫米波FMCW雷达液位计测距原理,针对影响测距精度的FFT栅栏效应问题,提出了将Zoom FFT和能量重心校正算法结合的高精度信号处理算法.该算法通过FFT算法锁定感兴趣的差频信号频谱范围,采用Zoom FFT在此范围内进行频谱细化,后利... 本文基于毫米波FMCW雷达液位计测距原理,针对影响测距精度的FFT栅栏效应问题,提出了将Zoom FFT和能量重心校正算法结合的高精度信号处理算法.该算法通过FFT算法锁定感兴趣的差频信号频谱范围,采用Zoom FFT在此范围内进行频谱细化,后利用能量重心校正算法对细化后的频谱进行频率校正,从而获得差频信号的精确频率信息,并通过换算得到雷达到液面的距离.仿真结果表明,该算法能将雷达液位计的测距精度提高到毫米量级,计算量和运算存储空间比较合理. 展开更多
关键词 FMCW雷达 液位计 测距 ZOOM FFT 能量重心校正
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视觉资源数字对象格式与精度研究 被引量:3
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作者 彭建波 史国祥 孙劲松 《大学图书馆学报》 CSSCI 北大核心 2009年第6期46-49,共4页
在文献调研、网络调研、实地走访和实验的基础上,对视觉资源数字对象常用的GIF、JPEG、JPEG2000、TIFF、DjVu等格式进行了分析,指出JPEG是视觉资源数字化过程中得到广泛应用的一种成熟格式,JPEG2000是一种较好的替代格式;DjVu格式不适... 在文献调研、网络调研、实地走访和实验的基础上,对视觉资源数字对象常用的GIF、JPEG、JPEG2000、TIFF、DjVu等格式进行了分析,指出JPEG是视觉资源数字化过程中得到广泛应用的一种成熟格式,JPEG2000是一种较好的替代格式;DjVu格式不适合视觉资源的数字化;视觉资源数字化的最佳格式模式是采用600dpi全彩色TIFF格式进行扫描,再将扫描文件转换为300dpi的JPEG2000格式,采用DeepZoom技术进行网络呈现。 展开更多
关键词 视觉资源 数字化 图像格式 DEEP ZOOM
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