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Anisotropy of Trabecular Bone from Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jian-Feng Chen 《Open Journal of Radiology》 2024年第1期14-23,共10页
Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions... Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age. 展开更多
关键词 ANISOTROPY Trabecular Bone Score Bone Mineral Density Ultra-Distal Radius digital x-ray Image
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Digital Generative Multimedia Tool Theory (DGMTT): A Theoretical Postulation
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作者 Timothy Ekeledirichukwu Onyejelem Eric Msughter Aondover 《Journalism and Mass Communication》 2024年第3期189-204,共16页
The development of digital technology has brought about a substantial evolution in the multimedia field.The use of generative technologies to produce digital multimedia material is one of the newer developments in thi... The development of digital technology has brought about a substantial evolution in the multimedia field.The use of generative technologies to produce digital multimedia material is one of the newer developments in this field.The“Digital Generative Multimedia Tool Theory”(DGMTT)is therefore presented in this theoretical postulation by Timothy Ekeledirichukwu Onyejelem and Eric Msughter Aondover.It discusses and describes the principles behind the development and deployment of generative tools in multimedia creation.The DGMTT offers an all-encompassing structure for comprehending and evaluating the fundamentals and consequences of generative tools in the production of multimedia content.It provides information about the creation and use of these instruments,thereby promoting developments in the digital media industry.These tools create dynamic and interactive multimedia content by utilizing machine learning,artificial intelligence,and algorithms.This theory emphasizes how crucial it is to comprehend the fundamental ideas and principles of generative tools in order to use them efficiently when creating digital media content.A wide range of industries,including journalism,advertising,entertainment,education,and the arts,can benefit from the practical use of DGMTT.It gives artists the ability to use generative technologies to create unique and customized multimedia content for its viewers. 展开更多
关键词 digital generative tools multimedia creation THEORY artificial intelligence machine learning techniques
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Generative Adversarial Networks Based Digital Twin Channel Modeling for Intelligent Communication Networks 被引量:2
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作者 Yuxin Zhang Ruisi He +5 位作者 Bo Ai Mi Yang Ruifeng Chen Chenlong Wang Zhengyu Zhang Zhangdui Zhong 《China Communications》 SCIE CSCD 2023年第8期32-43,共12页
Integration of digital twin(DT)and wireless channel provides new solution of channel modeling and simulation,and can assist to design,optimize and evaluate intelligent wireless communication system and networks.With D... Integration of digital twin(DT)and wireless channel provides new solution of channel modeling and simulation,and can assist to design,optimize and evaluate intelligent wireless communication system and networks.With DT channel modeling,the generated channel data can be closer to realistic channel measurements without requiring a prior channel model,and amount of channel data can be significantly increased.Artificial intelligence(AI)based modeling approach shows outstanding performance to solve such problems.In this work,a channel modeling method based on generative adversarial networks is proposed for DT channel,which can generate identical statistical distribution with measured channel.Model validation is conducted by comparing DT channel characteristics with measurements,and results show that DT channel leads to fairly good agreement with measured channel.Finally,a link-layer simulation is implemented based on DT channel.It is found that the proposed DT channel model can be well used to conduct link-layer simulation and its performance is comparable to using measurement data.The observations and results can facilitate the development of DT channel modeling and provide new thoughts for DT channel applications,as well as improving the performance and reliability of intelligent communication networking. 展开更多
关键词 digital twin channel modeling generative adversarial networks intelligent communication networking
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A digital controlled alternating electromagnetic stirring generator based on dual inverter structure
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作者 张芩 谢芳祥 +2 位作者 朱磊 叶惠 王振民 《China Welding》 EI CAS 2015年第4期74-80,共7页
A digital controlled alternating electromagnetic stirring generator is proposed in this paper. The main circuit of the generator makes use of dual inverter structure among which the former inverter uses full bridge ze... A digital controlled alternating electromagnetic stirring generator is proposed in this paper. The main circuit of the generator makes use of dual inverter structure among which the former inverter uses full bridge zero voltage switching topology and the latter inverter uses full bridge inverter circuit. To improve the dynamic response performance, the inverting frequency of the former inverter is as high us 100 kHz. The Cortex-M3 kernel based ARM microcontroller LM3S818 is adopted as the cybernetics core of the digital control system to achieve accurate, stable and flexible control of the generator. All the PWM signals for the former and latter inverters are generated by the LM3S818 directly. The constant current characteristic of the former inverter is obtained through current close-loop feedback control, and can ensure the operation safety when the output current waveform is at zero crossing point. Both simulation and experiment results show that the proposed generator is with such advantages as wide soft-switching range, perfect control accuracy and flexible waveform modulation, and can fulfill the requirements of electromagnetic stirring process. 展开更多
关键词 electromagnetic stirring generator dual inverter digital control SOFT-SWITCHING ARM
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Design of Digital Hybrid Chaotic Sequence Generator
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作者 饶妮妮 曾东 《Journal of Electronic Science and Technology of China》 2004年第1期14-16,75,共4页
The feasibility of the hybrid chaotic sequences as the spreading codes in code divided multiple access(CDMA) system is analyzed. The design and realization of the digital hybrid chaotic sequence generator by very high... The feasibility of the hybrid chaotic sequences as the spreading codes in code divided multiple access(CDMA) system is analyzed. The design and realization of the digital hybrid chaotic sequence generator by very high speed integrated circuit hardware description language(VHDL) are described. A valid hazard canceledl method is presented. Computer simulations show that the stable digital sequence waveforms can be produced. The correlations of the digital hybrid chaotic sequences are compared with those of m-sequences. The results show that the correlations of the digital hybrid chaotic sequences are almost as good as those of m-sequences. The works in this paper explored a road for the practical applications of chaos. 展开更多
关键词 digital hybrid chaotic sequence generator VHDL code divided multiple access(CDMA)
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Full-field mapping of internal strain distribution in red sandstone specimen under compression using digital volumetric speckle photography and X-ray computed tomography 被引量:5
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作者 Lingtao Mao Jianping Zuo +1 位作者 Zexun Yuan Fu-Pen Chiang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期136-146,共11页
It is always desirable to know the interior deformation pattern when a rock is subjected to mechanicalload. Few experimental techniques exist that can represent full-field three-dimensional (3D) straindistribution i... It is always desirable to know the interior deformation pattern when a rock is subjected to mechanicalload. Few experimental techniques exist that can represent full-field three-dimensional (3D) straindistribution inside a rock specimen. And yet it is crucial that this information is available for fully understandingthe failure mechanism of rocks or other geomaterials. In this study, by using the newlydeveloped digital volumetric speckle photography (DVSP) technique in conjunction with X-ray computedtomography (CT) and taking advantage of natural 3D speckles formed inside the rock due to materialimpurities and voids, we can probe the interior of a rock to map its deformation pattern under load andshed light on its failure mechanism. We apply this technique to the analysis of a red sandstone specimenunder increasing uniaxial compressive load applied incrementally. The full-field 3D displacement fieldsare obtained in the specimen as a function of the load, from which both the volumetric and the deviatoricstrain fields are calculated. Strain localization zones which lead to the eventual failure of the rock areidentified. The results indicate that both shear and tension are contributing factors to the failuremechanism. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 Red sandstone Strain localization Uniaxial compression digital volumetric speckle photography(DVSP) x-ray micro-tomography
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Teaching Design of Course Building Decoration Materials Based on Generative Artificial Intelligence
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作者 LIU Yanan HONG Xiaochun QIAN Liang 《Journal of Landscape Research》 2024年第3期83-87,共5页
With the digital transformation of global education and China's emphasis on education digital,generative AI technology has been widely used in the field of higher education.In this paper,the development of generat... With the digital transformation of global education and China's emphasis on education digital,generative AI technology has been widely used in the field of higher education.In this paper,the development of generative AI technology and its potential in personalized learning,interactive content creation and adaptive assessment in education were introduced firstly.Then,the application case of generative AI tools in teaching content creation,scenario-based teaching content development,visual teaching content development,complex concept deconstruction and analogy,student-led application practice and other aspects in the teaching of Building Decoration Materials was discussed.Through the teaching experiment and effect evaluation,the positive influence of generative AI technology on the improvement of students'learning effect and teaching efficiency was verified.Finally,some thoughts and inspirations on the combination of educational theory and generative AI technology,the integration of teaching design and generative AI technology,and the practice cases and effect evaluation were put forward,and the importance of teacher role transformation and personalized learning path design was emphasized to provide theoretical and practical support for the innovative development of higher education. 展开更多
关键词 generative artificial intelligence Higher education Teaching design Education digitization
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Rapid digitalization and panoramic evaluation of weld X-ray film
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作者 闫志鸿 宋永伦 +1 位作者 王彬 李元香 《China Welding》 EI CAS 2011年第1期49-53,共5页
The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT ( nondestructive testing). To achieve this target, digitalization of film is the first step and automatic defect identification... The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT ( nondestructive testing). To achieve this target, digitalization of film is the first step and automatic defect identification is another key technique. In this paper, a weld X-ray film digitalizing system has been established with linear array CCD and highlight LED light source. Its space resolution can reach 0. 04 mm/pixel and scanning speed can reach 100 mm/s for an industrial film. The transfer function curves of the system have been measured and the results indicate that its image gray resolution can reach 88 G/D at 4. 5D, and its dynamic range can be wider than 2. OD. In order to facilitate the evaluation of large welded structure, a panoramic evaluation algorithm is developed also. The algorithm includes image matching, image fusion and panoramic evaluation of the long linked film image. 展开更多
关键词 weld x-ray film rapid digitalization image processing panoramic evaluation
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Application of X-ray digital tomosynthesis in knee joint trauma examination
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作者 Li-Sheng Wu You-Jun Lin +1 位作者 Xiao-Ling Yi Hai-Na Xu 《Journal of Hainan Medical University》 2018年第7期84-86,共3页
Objective: To explore the clinical value of X-ray digital tomosynthesis(DTS)in the diagnosis of knee joint fractures. Methods: A total of 28 cases of thoracic trauma, X-ray film cannot be clearly diagnosed or can conf... Objective: To explore the clinical value of X-ray digital tomosynthesis(DTS)in the diagnosis of knee joint fractures. Methods: A total of 28 cases of thoracic trauma, X-ray film cannot be clearly diagnosed or can confirm the diagnosis but the need for further identification of forensic diagnosis of cases of DTS scan and three-dimensional reconstruction in order to control the study. Results: 1. The reconstructed images after DTS scanning showed that the knee joint fractures were clearly diagnosed, and the detection rate of 28 knee joint fractures was 92.86%. 2. DTS scanning could clearly detect the fresh knee joint fracture's fracture line, corresponding line and broken bones. For the old fracture, DTS scanning could clearly show the condition of the fracture end's healing. Conclusions: The technique is of great value in the diagnosis of knee joint fracture, especially in the examination of complex structure, thick body and review of internal fixation after fracture. 展开更多
关键词 x-ray KNEE joint digital TOMOSYNTHESIS Fracture Diagnosis
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Research on Influence of Electromagnetic Interference on X-Ray Digital Detection
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作者 Guo Taotao Wang Dada +1 位作者 Guo Tieqiao Yu Hong 《Electricity》 2012年第5期38-43,共6页
X-ray digital imaging technology has found wide application owing to its advantages of real-time, visualization and rapid imaging. In substations the substantial electromagnetic interference has some influence on the ... X-ray digital imaging technology has found wide application owing to its advantages of real-time, visualization and rapid imaging. In substations the substantial electromagnetic interference has some influence on the live detection by the X-ray digital imaging technology, hindering the promotion of the technology in the detection of electric equipment. Based on a large number of field tests, the author carded out a series of researches on electromagnetic interference protection measures, image de-noising, and image enhancement algorithms. 展开更多
关键词 SUBSTATION live detection x-ray digital imaging electromagnetic interference image de-noising image enhancement
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Imaging Analysis of Trabecular Bone Texture Based on the Initial Slope of Variogram of Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jianfeng Chen Qifeng Ying 《Open Journal of Radiology》 2022年第3期78-85,共8页
Background: When applied to trabecular bone X-ray images, a method for analyzing trabecular bone texture based on the initial slope of variogram (ISV) was used to assess the trabecular bone health. Methodology: Data f... Background: When applied to trabecular bone X-ray images, a method for analyzing trabecular bone texture based on the initial slope of variogram (ISV) was used to assess the trabecular bone health. Methodology: Data from more than two hundred subjects were retrospectively studied. For each subject, a DXA (GE Lunar Prodigy) scan of the forearm was performed, and bone mineral density (BMD) value was measured at the location of ultra-distal radius, X-ray digital image of the same forearm was taken on the same day, and ISV value over the same location of ultra-distal radius was calculated. Pearson’s correlation coefficients were calculated to examine the correlation between BMD and ISV of the trabecular bones located at the same ultra-distal radius. ISV values changed with subjects’ age were also reported. Results: The results show that ISV value was highly correlated with the DXA-measured BMD of the same trabecular bone located at the ultra-distal radius. The correlation coefficient between ISV and BMD with the 95% confident was 0.79 ± 0.09. They also demonstrated that the age-related changes in trabecular bone health and differentiated age patterns in males and females, respectively. The results showed that the decrease in BMD was accompanied by a decrease in the initial slope of variogram (ISV). Conclusions: This study suggests that ISV might be used to quantitatively evaluate trabecular health for osteoporosis and bone disease diagnosis. 展开更多
关键词 Trabecular Bone Texture digital x-ray Image Bone Mineral Density Ultra-Distal Radius Initial Slope of Variogram
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The Impact of User-Generated Content in the Product Management Process of Digital Games
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作者 Judith Gerlach Daniel Schultheiss Anja Solf 《通讯和计算机(中英文版)》 2011年第10期855-862,共8页
关键词 数字游戏 管理过程 用户 客户忠诚度 客户满意度 顾客忠诚 产品 顾客满意
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基于System Generator开发数字信号处理系统 被引量:12
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作者 牛斌凯 雍少为 +1 位作者 张建 陈亮 《舰船电子工程》 2010年第1期129-132,共4页
在分析了传统数字信号处理开发方法不足的基础上提出采用基于SysGen的数字信号处理系统开发方法,并应用新方法设计验证了一套数字下变频系统,实验证明SysGen在数字信号处理开发方面具有明显优势。
关键词 SIMULINK system generator for DSP 数字下变频
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基于System Generator的数字下变频设计 被引量:8
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作者 陈蕾 姚远程 《电子设计工程》 2012年第24期74-78,共5页
Xilinx公司推出的DSP设计开发工具System Generator是在Matlab环境中进行建模,是DSP高层系统设计与Xilinx FPGA之间实现的"桥梁"。在分析了FPGA传统级设计方法的基础上,提出了基于System Generator的系统级设计新方法,并应用... Xilinx公司推出的DSP设计开发工具System Generator是在Matlab环境中进行建模,是DSP高层系统设计与Xilinx FPGA之间实现的"桥梁"。在分析了FPGA传统级设计方法的基础上,提出了基于System Generator的系统级设计新方法,并应用新方法设计验证了一套数字下变频系统,通过仿真和实验结果验证了该方法的有效性和准确性。 展开更多
关键词 数字下变频 多级抽取滤波 Systemgenerator FPGA
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基于System Generator的QPSK数字调制器设计 被引量:1
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作者 刘占线 《电子科技》 2011年第8期31-32,35,共3页
介绍了QPSK调制的基本原理,给出了QPSK调制器的系统模型设计,该设计是基于System Generator设计平台,在Matlab/Simulink环境下搭建系统模型,再进行功能仿真和验证,完成QPSK调制器的设计。仿真结果表明,所设计的调制器能产生正确QPSK波形... 介绍了QPSK调制的基本原理,给出了QPSK调制器的系统模型设计,该设计是基于System Generator设计平台,在Matlab/Simulink环境下搭建系统模型,再进行功能仿真和验证,完成QPSK调制器的设计。仿真结果表明,所设计的调制器能产生正确QPSK波形,达到了预期效果。 展开更多
关键词 SYSTEM generator QPSK 数字调制
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基于System Generator/CORDIC算法实现高精度鉴频 被引量:1
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作者 蔡雪颖 秦永左 刘立 《长春工业大学学报》 CAS 2013年第3期313-318,共6页
基于System Generator实现了CORDIC(Coordinate Rotation Digital Computer)算法的FM信号高精度鉴频。进行了模型构建,算法中16次旋转后的仿真得到最大误差为±3.051 757 781 25×10^(-5)rad/s的鉴频结果。
关键词 数字鉴频 CORDIC算法 SYSTEM generator
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REALIZATION OF FUZZY-FILTER CONTROL ON A BRUSHLESS AC GENERATOR 被引量:2
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作者 陈志辉 严仰光 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第3期172-176,共5页
The transistor voltage regulators have been widely adopted in the brushless AC generators in aircraft. This paper researches the digital voltage regulator. The paper presents the hardware platform of the digital volta... The transistor voltage regulators have been widely adopted in the brushless AC generators in aircraft. This paper researches the digital voltage regulator. The paper presents the hardware platform of the digital voltage regulator, which is based on a DSP chip — TMS320C32. A novel fuzzy filter control structure is developed from normal fuzzy control strategy. And the fuzzy filter control algorithm is adopted in the hardware platform successfully. The computer simulation has been conducted. Some control parameters have been obtained through the simulation. The same parameters have been applied in the digital regulation experiments on a brushless AC generator. In the experiment, the digital voltage regulator results in good responses. From the experiment results, it can be seen that the new control algorithm is efficient for the digital voltage regulator. 展开更多
关键词 voltage regulator fuzzy control brushless AC generator (BLACG) FILTER digital signal processor (DSP)
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Design of speed controller for electronic fuel injection gasoline generator based on feed-forward PID control
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作者 赵自庆 刘昌文 张平 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第4期354-363,共10页
As for the application of electronic fuel injection (EFI) system to small gasoline generator set, mechanical speed controller cannot be coupled with EFI system and has the shortcomings of lagged regulation and poor ... As for the application of electronic fuel injection (EFI) system to small gasoline generator set, mechanical speed controller cannot be coupled with EFI system and has the shortcomings of lagged regulation and poor accuracy, a feed-forward control strategy based on load combined with proportional-integral-differential (PID) control strategy was proposed, and a digital speed controller applied to the electrical control system was designed. The detailed control strategy of the controller was intro- duced. The hardware design for the controller and the key circuits of motor driving, current sampling and angular signal captu- ring were given, and software architecture was discussed. Combined with a gasoline generator set mounted with EFI system, the controller parameters were tuned and optimized empirically by hardware in loop and bench test methods. Test results show that the speed deviation of generator set is low and the control system is stable in steady state; In transient state the control system responses quickly, has high stability under mutation loads especially when suddenly apply and remove 100% load, the speed deviation is within 8% of reference speed and the transient time is less than 5 s, satisfying the ISO standard. 展开更多
关键词 gasoline generator digital speed controller electronic fuel injection (EFI) feed forward proportional-integral-differential (PID) control
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基于System Generator的数字滤波器实现与优化 被引量:1
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作者 郑鹤 钱林杰 《电子世界》 2012年第21期127-129,共3页
FPGA是数字信号处理的理想器件,数字信号处理涉及到大量滤波器的设计与实现。本文详细介绍了基于System Generator的数字滤波器的设计与实现,并且根据FPGA的特性对滤波器进行了优化。
关键词 数字滤波器 SYSTEM generator 实现 优化
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一种基于System Generator的CORDIC算法实现 被引量:4
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作者 胡天翔 陈科 赵志强 《科技创新与应用》 2020年第19期23-27,31,共6页
在现场可编程门阵列(FPGA)芯片的应用中,选择坐标旋转数字计算(CORDIC)算法来实现正余弦函数的实时计算有着广泛的应用。同时在信号处理领域上,对正余弦函数的计算有着高精度的需求。据此采用Simulink平台的Xilinx公司开发工具System Ge... 在现场可编程门阵列(FPGA)芯片的应用中,选择坐标旋转数字计算(CORDIC)算法来实现正余弦函数的实时计算有着广泛的应用。同时在信号处理领域上,对正余弦函数的计算有着高精度的需求。据此采用Simulink平台的Xilinx公司开发工具System Genenrator(SysGen)设计了基于CORDIC算法实现正余弦函数计算的FPGA模型,将角度计算范围扩展到全实数领域,并在理论上推导出该设计方案计算结果的误差上限。仿真结果显示,该设计方案的误差精度与理论推导保持一致。而且,相比SysGen的系统自带模块,该设计可以避免重复尝试,更好地控制计算精度。 展开更多
关键词 坐标旋转数字计算机 现场可编程门阵列 正余弦函数 计算精度 System generator
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