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1.
In order to accelerate the working speed of a FFT processor, this paper presents a hardware structure of a FFT processor, which is suitable for CPLD , and the 128-point FFT single-chip processor is realized by means of FLEX10K CPLD and MAX+PLUS II software. The calculation time of the processor is less than 230uS. The research proves that the combination of CPLD and FFT increases the working speed of FFT processors and raise the level of application .  相似文献   

2.
A pipelined FFT processor designed for fast and real-time requirements with FPGA is introduced. This FFT processor can be used to real-time frequency analysis and its working frequency can reach to 75 MHz. The leakage error is reduced through multiply the sampled signal by a weighting window. In order to improve FFT's working frequency and economize FPGA resources, an algorithm of 1024-point complex to compute 2048-point real data is adopted. In addition, an approximate algorithm to compute module value of complex number is introduced.  相似文献   

3.
阐述了晋鲜糯系列玉米品种晋鲜糯1号、晋鲜糯2号、晋鲜糯6号、晋鲜糯8号等的特征特性,及其优质高效栽培技术,旨在为种植、生产、加工甜糯玉米的种植者、加工厂家提供参考依据,以便更好地实现特色玉米、专用玉米的优质与高效生产。  相似文献   

4.
Processing chamber is an important part of high-frequency electromagnetic water processor. To determine what kind of processing chamber has better effect of antiscaling, the software, Ansoft Maxwell, which is based on the finite element method, is applied to simulate electromagnetic energy distribution in two common processing chambers. One processing chamber is set with coaxial electrodes and the other one is wrapped by spirals. The electromagnetic energy released to water and the distribution of instantaneous energy density of each chamber are compared. According to the simulation analysis, when the same electrical excitation is imposed on the same volume of water, electromagnetic energy of processing chamber with coaxial electrodes is far more than that of processing chamber wrapped by spirals. However, the electromagnetic energy of processing chamber with coaxial electrode decreases from the anode to the cathode, while the electromagnetic energy of processing chamber wrapped by spirals is distributed evenly. These analysis results can be definitely instructive to design the chamber of high-frequency electromagnetic processor.  相似文献   

5.
A video Monitor &Control system of tunnel based on DSP/BIOS is proposed,which is different from traditional video Monitor & Control system.It uses DSP to process image,and uses enhanced video input processor to qcquire image.This system satisfies all requirements of video supervision,and is a low cost system.It has a good application foreground.The system has been confirmed as a good veracity and practicability system through testing in the Zhongliang Mountain tunnel of Chongqing.  相似文献   

6.
As a kind of data compression technique of high efficiency, arithmetic coding is widely used in image compressing. This paper introduces the adaptive binary arithmetic coding used in the new international standard of still image compression named jpeg2000. The implementation of arithmetic coding depends on high power digital signal processor.Fast adaptive binary arithmetic coding and optimized assembly program design are discussed, and its practicability and efficiency are proved.It also can be used in other fields that need compressing data.  相似文献   

7.
Aiming at the shortcoming of low recognition and training speed in embedded speaker - recognition system based on DS Phard-core processor, a new scheme of system based on FPGA and vector quantization principle is presented. In the speaker-recognition system based on the vector quantization and generation algorithm, a fitness parallel process hardware structure is presented by the scheme which consumes much less time than software processing while getting the fitness. The test shows that the system uses this method obtains both high recognition rate and higher speed in training and recognition.  相似文献   

8.
In regard to stochastic and suddenly varying data,a new kind of data processor algorithm based on adaptive prediction is presented.The algorithm describes the changing pattern of measured variables by means of time series models with slowly time-varying parameters,forms the criterion by use of the adaptive and its 95% belief limit,and processes the measured data so as to reject or restrain outliers mixed in them.The simulation example indicates that the algorithm surmounts difficulties which most current algorithms encounter when processing stochastic and suddenly varying data and that it is of obvious effects.  相似文献   

9.
The architecture of scalable length and high speed FFT processor based on CPLD(Complex Programmable Logic Device) is proposed, including the pipeline architecture of the radix mixed FFT algorithm, the address regularity of the read-then-write RAM, the array architecture of short-length FFT and the pipeline complement architecture of CORDIC(Coordinate Rotation Digital Computer) algorithm. If the input-data velocity is 20 MHz,the time expended on 1024-point FFT is 50 us.  相似文献   

10.
According to the motors working principle, the authors design and complet an electronic fuel injection system based the monolithic processor of MC68HC08. Then the authors complete a matching experiment of single-plunger fourstroke engine CG125 applying this system to the trestle. As the system used, fairly well has been settled the contradiction among the driving force of engine, the economization of fuel consumption and the letting of exhaust gas. After the testing, the power of motorcycle engine has increased about 10%, the oil consumption has decreased about 15 %, and the exhaust gas has decreased about 20%,  相似文献   

11.
Direct memory access(DMA)is an important technology used for fast speed data transfer in data signal processor(DSP). DMA is able to move data block independent of CPU, and this capability meets real time image processing. TMS320C6201 DSP is taken as an example, and DMA controller characteristic is introduced. According to DMA application in realtime image processing, the specific control ways and realization steps are given out. The research result shows that the flexible control DMA can not only raise image data transfer efficiency but also improve DSP speed.  相似文献   

12.
The DSP(digital signal processor) of TMS320C6000 series,has a special structure VLIW(very long instruc-tion word),which makes the functions of hardware depend on the efficiency of software.Therefore,when DSPs of thisseries are used to design a real-time tracking system,the executing efficiency of software will directly affect the real-timespeciality of the system.Several methods of optimizing software based on C6000 DSPs are researched,including choo-sing compiler options,use of DS Pkey words and intrinsics,data packed and software pipelining.Optimizing software ofthe whole system by using these methods,primely can solve the problem of bad real-time in processing.Consequently,the stability of the whole system is improved.  相似文献   

13.
在农作物金银花干燥期间,为了满足干燥热风的温度和风速的稳定性要求,针对热风炉出风口热风温度与设定的温度值滞后和稳定性差等问题,设计了一套以单片机STM32作为核心处理器和模糊自适PID算法作为参数控制器的控制系统,实现模糊自适PID算法对参数进行调整。利用Matlab语言建立模型,对整套控制系统进行仿真分析。结果表明:出风口热风温度的稳定性能达到95%以上,该研究方法提高控制系统的性能,有利于农作物干燥的质量和效率。  相似文献   

14.
In the era of "post-PC", embedded system is regarded as a new representation. And its characteristics and developing technology are focused. The traits of embedded system, which are low power processor, compact operating system, prolifically peripheral interfaces and form, and its inner modularized framework are parsed. The typical developing pattern of embedded system is put forward,which is called Host-Target pattern . This pattern can make developers have clear design train of thoughts and divide the work, and also make the developing synchronously. And cross-compile and remote debug is the typical developing characteristics of Host-Target pattern. They are both discussed in this article. Finally we prospect the future of embedded system, and the network, system on chip (SOC) and lower cost of embedded systems are regard as its tendency by author.  相似文献   

15.
The damage of bridge cable directly hazards the normal use of bridge and the safety of people. The paper discussed the signal acquisition and detection system which takes embedded DSP processor as core technology, combined with CCD, video decode chip, SDRAM, FLASH ROM, and established the fast measuring algorithm of the surface corrosion and damage, which includes deteminating the processing region, improving medium filter, sobel edge detection and dynamic threshold segment, close operation of morphology, computing defect area and saving. The experimental resuits show that this method implemented the real-time, non-contact and intelligence detecting of cable surface defect and gives the specifications of the system.  相似文献   

16.
The hardware architecture and instruction set of the digital signal processor leads to its high speed and precision in processing data. Aiming at the virtual instrument's deficiency in speed and precision resulting from the limit of the computers' development, the author brings forward a method to promote the performance of the virtual instruments using the DSP technology. Implementing the complex algorithms in DSP and using the principal and subordinate DSP structure or DMA technology in the data acquisition card of the virtual instrument can promote the virtual instrument's real-time characteristic greatly. Several key technologies are introduced in realizing the data acquisition and processing card. The experiment shows that the digital signal processors have higher speed and precision than the computers when implementing complex algorithms, and that using the DSP to implement the algorithms is an effective method to promote the virtual instrument's performance.  相似文献   

17.
In this study, the cold chain and its impact on food stuff microbiology was evaluated for fresh-cut endive. A survey was carried out to analyze endive temperature throughout the supply chain from producer, via processor and distributor to the restaurant. Data loggers accompanying the endive on its route provided a temperature profile of the endive. The effect of the outdoor temperature on initial cooling was evaluated and critical points regarding cold chain management in the supply chain were identified. Our experiments indicate that the cold chain is generally properly maintained. In parallel with temperature monitoring, indicator microorganisms were assessed at different points in the supply chain to examine the effects of endive temperature, temperature fluctuations, and the outdoor temperature on microbial food safety. Small temperature fluctuations in the supply chain had a small effect on the total level of aerobic mesophilic bacteria. However, at the best before-date, total coliforms and Enterobacteriaceae levels were significantly higher in endive samples subject to temperature fluctuations in the supply chain, compared to endive stored in optimal conditions. To our knowledge, this is the first study that combines microbiological analysis with the temperature profile of fresh-cut produce in a realistic food supply chain.  相似文献   

18.
复合磁场处理对玉米种子萌发及幼苗生长发育的影响   总被引:4,自引:1,他引:3  
为了探讨复合磁场处理对玉米生物学效应的影响, 采用 ZS-CⅢ型复合磁化处理机交变电流产生的复合磁场, 磁场强度为(A)250 mT和(B)300 mT的磁场分别处理玉米种子的方法, 以国审品种 ‘郑单958’ 、 河南省审定品种 ‘郑单 2201’ 、 以及杂交组合 12HY617×12HY741、 12HY647×12HY741、 12HY751×12HY601、 12HY576×12HY436、 12HY731×12HY592 为试验材料, 未处理的对应玉米种子为对照组(CK), 研究复合磁场处理对玉米种子发芽及苗期生长的影响。结果表明: 复合磁场处理后玉米种子的发芽势、 发芽率均有提高, 最大提高幅度分别为 26.7%和 30.4%; 叶绿素含量比对照提高了 8.17%~28%;玉米苗期根、 茎和叶的干重、 鲜重、 根长均比对照有增加, 达到显著或极显著水平; 对苗期茎长影响不显著; 以上指标在 A、 B两种磁场强度处理之间差异不显著。因此适宜复合磁场处理可以显著提高玉米种子的发芽率、 发芽势和叶片中叶绿素的含量, 增加苗期根长、 根、 茎和叶的干重、 鲜重, 为玉米增产打下良好的基础。  相似文献   

19.
关于打造农业精品期刊的思考   总被引:3,自引:0,他引:3  
甘海燕 《中国农学通报》2005,21(9):414-416,429
详细分析了制约农业精品期刊产生的主要因素,提出通过采取树立品牌意识,明确刊物定位,突出办刊特色,打造一支高素质复合型的人才队伍,发展集团化经营等系列措施,打造农业精品期刊。  相似文献   

20.
姚乌兰  张增艳  陈亮  辛志勇 《作物学报》2007,33(9):1405-1410
应用RT-PCR、RACE技术,从病原诱导的中间偃麦草叶片cDNA中,分离出1个编码ERF基因的全长cDNA序列,该基因暂命名为TiERF1a,编码由292个氨基酸组成的蛋白质,具有ERF转录因子典型的结构,即保守的AP2/ERF DNA 结合域、核定位位点和酸性激活区。TiERF1a的氨基酸序列与一个水稻ERF蛋白OsBIERF3具有66%的同源性,与拟南芥AtERF1同源性仅39.7%,为植物ERF转录因子家族B3亚群的一个新成员。表达分析结果表明,纹枯病菌、赤霉病菌侵染可诱导TiERF1a基因的上调表达,与防卫相关的激素乙烯、茉莉酸也可诱导该基因上调表达,且TiERF1a对外源乙烯、茉莉酸的响应时期早于对纹枯病菌、赤霉病菌响应时期,说明TiERF1a可能通过乙烯、茉莉酸信号途径参与寄主调控对纹枯病菌、赤霉病菌的防御反应。  相似文献   

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