数字化模拟

According to the demand of high magnetic field power supply, reference is increased with a set ramp rate and stops at a set stable value, so reference system is composed of digital setting and digit to analog converting circuit. But the stability of reference is mostly guaranteed by the performance of D/A circuit, so D/A circuit is particularly studied in reference system. The scheme of D/A circuit, the selection of DAC and its voltage reference, hardware anti-jamming design and PCB design are discussed in detail, and software of remote control and PLC are discussed in brief. Zero-flux DC current transformer well satisfies the demands of the high stability of Load current detection unit, so the principle of zero-flux DC current transformer is analyzed; in the mean time a project which detects the long term stability is designed. During 8 hours, analog signal which is detected with high precision digit multimeter is recorded in computer at 1HZ frequency by GPIB communication. The drift error source and related parameters are explained in the compare-amplify part. Detailed subtraction circuit is designed; also amplifier chip and periphery components are selected and verified according to the theory of error analysis.

根据强磁场电源的需求，参考源应按照软件设定的斜率逐渐上升到设定稳态值，则参考源系统应由数字给定和数模转换电路两大部分组成，而参考源的稳定度主要依靠完成数模转换功能的模拟电路的性能来保证，因此本文对参考源系统的研究以数模转换电路为重点，分别从电路方案的确定、数模转换芯片及其基准电压源的选取和验证、电路板硬件抗干扰和PCB设计几方面进行了论述，然后对数字给定部分的远控组态和PLC程序设计作了简要介绍；采用零磁通原理的直流电流转换器很好地满足了对负载电流检测单元高稳定度的需求，本文详细分析了零磁通检测的原理，并在选定此种类型电流转换器的基础上设计了一套检测长期稳定度的方案，8小时内以1秒为采样周期，通过计算机Labview程序和高精度数字电压表的GPIB通讯，将被高精度数字电压表数字化后的模拟信号采样值连续记录至计算机中；比较放大环节简要阐述了漂移产生的原因和相关参数指标，确定了具体的减法电路形式，并根据误差分析理论对运算放大器和外围元器件进行了选取和验证。

With the development of worldwide digitalization, the trend of digital television channel displacing the traditional TV appears more and more obvious.

全球都在数字化，电视由模拟向数字化的转移是一个不可逆转的发展方向。

At the beginning of all things in the trend of digital and traditional analog to digital surveillance network to monitor the transformation has become an inevitable trend.

在一切事物都开始数字化的潮流中，传统模拟监控向数字化网络化监控的转化已经成为一种必然的趋势。

the digitized mapping technique is to combine the field data collection system with the computer assisted mapping system in surveys by computer technology.it aims to realize the information collected and processed digitally and automaticaity.the digitized mapping technique can cut short the working time,lighten the labor intensity and enhance the precision of the productions.the system consists of three parts,such as data input,data processing and data output.the survey-record digitized mapping technique is widely used in the digitized mapping working pattern.for its superiority over traditional plane-table mapping in accuracy and efficiency,the large scale digital mapping is becoming more and more popular.compared with traditional analogue mapping,digital mapping has more quality control pivotai points,and its contents and methods are more complex.with the appearance of new technology gps ,the coordinate of different levels controlling points may be surveyed in high precision and it has been applied widely in topographic survey.the operation process of gps electronic tachometer is introduced and its application in topographic survey is br

计算机应用论文，计算机论文， rtk ，全站仪，数字测图，地形测量， gps论文摘要：数字测图是在测量工作中利用电子计算机技术将野外数据采集系统与内业机助制图系统相结合，其目标是实现信息采集处理的数字化、自动化、信息化。数字测图可以缩短作业时间，减轻劳动强度，提高成果精度。数字测图系统主要由数据输入、数据处理和数据输出3部分组成，数字测图作业模式中测记式数字测图应用最为广泛。大比例尺数字测图正以其测图精度高，成图速度快等优势逐步的取代传统的，以平板仪为主的模拟测图。与传统的模拟测图相比，数字测图的质量控制关键点更多、内容与方法更为复杂。gps 新技术的出现，可以高精度并快速地测定各级控制点的坐标，在地形测量中已得到广泛地应用。本文介绍了gps 配合全站仪的作业流程，简要阐明了其在地形测量中的应用。在利用实测数据成图的过程中，解决一些常见的问题，并给出解决的办法及依据，同时给出一些有益的结论，以适应实际使用的需要。

Based on the whole year datum of 251 examination items recorded by 102 digital stations of earthquake underground fluid in 2003, systemically summarizing the distribution of digital stations, quality of the datum , the joint between the digital datum and simulative datum , and so on in china, there is a comparison analysis on the actuality of digital observation of earthquake underground fluid and part of means between homeland and fremdness, preminarily discussing the questions of digital monitoring for earthquake underground fluid in china.

以2003年全国地震地下流体数字化的102个台站的251个测项的全年资料为基础，系统总结了全国数字化台站的分布、资料的质量、数字化资料和模拟资料的衔接情况等，并就目前我国地震地下流体数字化监测的现状和国内外的部分手段进行了对比分析，初步探讨了我国地震地下流体数字化监测中存在的问题。

Based on the whole year datum of 251 examination items recorded by 102 digital stations of earthquake underground fluid in 2003, systemically summarizing the distribution of digital stations, quality of the datum, the joint between the digital datum and simulative datum, and so on in china, there is a comparison analysis on the actuality of digital observation of earthquake underground fluid and part of means between homeland and fremdness, preminarily discussing the questions of digital monitoring for eart...

以2003年全国地震地下流体数字化的102个台站的251个测项的全年资料为基础，系统总结了全国数字化台站的分布、资料的质量、数字化资料和模拟资料的衔接情况等，并就目前我国地震地下流体数字化监测的现状和国内外的部分手段进行了对比分析，初步探讨了我国地震地下流体数字化监测中存在的问题。

multi-channel correlators are widely used in traditional pseudo-random code cw radar,which makes the ranging system more complicated.this paper proposes a method of digitalizing the return signal directly and then convoluting the signals on dsp,which can replace multi-channel correlation in analog circuit.but the computation of convolution is too huge for the dsp to fulfill.to solve this problem,this paper analyzes five fast algorithms including fft,and then chooses one according to the characters of prc-cw radars.the digital method and fast algorithm have been verified by simulated signal and real signal.

一种提高空间伪码扩谱测距精度的实用。。。摘要：传统的伪码调相连续波雷达采用多路模拟相关电路实现对回波信号的相关接收，通过多路试探搜索各距离单元的目标，电路复杂。提出的数字化方案，对回波信号直接数字化，利用高速dsp实现数字卷积，可替代多路模拟相关电路。但是直接卷积的运算量过大，dsp无法承受。本文对此进行了研究，分析了包括fft在内的五种快速算法，结合prc-cw雷达的具体情况，确定了一种适于dsp实现的快速卷积算法。仿真和实测数据证实了数字化方案及快速算法的正确性。

multi-channel correlators are widely used in traditional pseudo-random code cw radar,which makes the ranging system more complicated.this paper proposes a method of digitalizing the return signal directly and then convoluting the signals on dsp,which can replace multi-channel correlation in analog circuit.but the computation of convolution is too huge for the dsp to fulfill.to solve this problem,this paper analyzes five fast algorithms including fft,and then chooses one according to the characters of prc-cw radars.the digital method and fast algorithm have been verified by simulated signal and real signal.

摘 要：传统的伪码调相连续波雷达采用多路模拟相关电路实现对回波信号的相关接收，通过多路试探搜索各距离单元的目标，电路复杂。提出的数字化方案，对回波信号直接数字化，利用高速dsp实现数字卷积，可替代多路模拟相关电路。但是直接卷积的运算量过大，dsp无法承受。本文对此进行了研究，分析了包括fft在内的五种快速算法，结合prc-cw雷达的具体情况，确定了一种适于dsp实现的快速卷积算法。仿真和实测数据证实了数字化方案及快速算法的正确性。

Digitalized virtual human project incorporates up-to-date scientific and technological achievements, digitalizes and visualizes human structures and functions. This study concentrates on the combination of medicine and computer techniques, and opens up many new f...

数字化虚拟人体集成了最新的科技成就，将人体结构和功能信息数字化与可视化，它的研究将在医学与计算机的结合上、在涉及人体模拟的许多方面开辟新的研究领域，也为针灸腧穴形态学的研究提供一个基础技术研究平台。

MD are analog sensors, the digitizing happens when the electrons are passed through the analog to digital converter. The A to D converter converts the analog signal to a digital file or signal.

CD 属于模拟传感器，当电子从模拟转换传输到数字转换器时实现数字化。A/D转换器将模拟信号转换到数字文件或信号。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。