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1.
信号采集的目的是了后续雷达成像和海浪信息提取。基于虚拟仪器技术,对单脉冲体制导航雷达设计了一套数据采集系统。以计算机和PXI-9820数据采集卡为硬件,以VC++6.0软件作为开发平台,构建了基于Windows平台的数据采集系统,雷达回波信号采集单元采用多路信号同步采集的设计方案,并指出了系统实现过程中的多通道同步采集的关键技术问题。东海某海域的岸基采样实验证明了基于虚拟仪器技术的数据采集器设计的可行性及系统运行的可靠性。  相似文献   

2.
采用虚拟仪器的思想,设计了一种基于声卡的数据采集系统。该采集系统在Lab VIEW程序开发环境下,能够实现声音信号的采集、播放和识别等功能。实验结果表明:系统能够正确采集声音频率范围内的信号,可用于该范围内的一般数据采集与应用。  相似文献   

3.
针对雷达接口信号测试复杂问题,提出了基于ARM9系列嵌入式平台作为硬件开发平台的雷达数据采集系统。将采集系统按照便携式数据采集系统和数据管理及分析系统两大分系统进行了详细阐述。  相似文献   

4.
介绍了基于虚拟仪器技术设计的温度测试系统。将高性能的数据采集卡PCI-1711与传感元件和调理电路于一体,构建成了温度测试硬件系统,软件基于Labview虚拟仪器开发平台,采用模块化设计,实现了检测信号的实时采集、数据处理、数据显示等功能。系统可应用于实验教学中。  相似文献   

5.
利用国产数据采集设备和虚拟仪器技术开发了机床切削力数据采集与处理系统,该系统可以具有信号采集.数据处理、存储以及图形显示等功能.  相似文献   

6.
基于虚拟仪器技术,设计了便携式的压力变送器检定系统。该系统以高精度智能压力表为标准表,以LabView为软件平台,通过计算机完成压力变送器的信号采集与转换,并与标准表进行对比。整个系统具有信号采集、误差计算、报表打印等功能,且携带方便,操作简单,可大大提高工作效率。  相似文献   

7.
通过HK-2000C集成化数字脉搏传感器结合虚拟仪器软件LabVIEW设计开发脉搏分析仪模块,构建出了虚拟人体脉搏采集系统,实现了虚拟仪器界面中脉搏信号的采集、存储、回放和处理,可应用于中医脉诊教学及实验.  相似文献   

8.
发动机台架试验系统是测试发动机动力性、经济性、可靠性的必要手段,其自动化水平与测试精度能够直接影响试验数据采集及分析处理的准确性。基于虚拟仪器LabVIEW设计了发动机台架试验数据采集系统,硬件部分主要包括实现发动机转速、温度、振动等信息获取的传感器,以及匹配传感器的信号调理模块和数据采集卡;软件部分是基于虚拟仪器LabVIEW编写的数据处理与界面显示程序。调试运行结果表明构建的发动机台架试验数据采集系统能够实现发动机转速特性、负荷特性、振动等信息的准确采集并能在界面窗口直观显示,能够满足发动机性能测试过程中运转特性参数信息准确获取的需求。  相似文献   

9.
基于CPLD和USB的高速数据采集系统的设计   总被引:4,自引:0,他引:4  
介绍了CPLD和USB在基于数据采集系统的虚拟仪器的应用。通过软、硬件技术的结合,实现了对多路模拟信号的采集和多种波形的输出,充分发挥了虚拟仪器的优势。该系统利用CPLD芯片及高速、高精度的ADS8364芯片和多通道的DAC7624/25芯片,开发了高速数据采集和波形发生器系统,并使用USB接口在主机中实现数据存储与显示。  相似文献   

10.
基于LabVIEW的信号处理系统   总被引:1,自引:0,他引:1  
介绍了以图形化编程语言LabVIEW为软件开发平台,通过数据采集卡和PC为硬件支撑,构建信号的采集和分析的虚拟仪器系统,该系统不仅实现了实时波形显示、电压有效值、信号频率等参数的计算,还将虚拟仪器技术运用到频谱分析中来,增强了仪器的功能,缩短了仪器的开发时间。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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