期刊文献+
共找到28篇文章
< 1 2 >
每页显示 20 50 100
基于PXI总线数模转换模块的设计
1
作者 程胜文 王俊平 秦建军 《福建电脑》 2003年第7期17-18,33,共3页
本文主要介绍了基于PXI总线的高精度数模转换模块的体系结构和设计思想,同时讨论了高速高精度数模转换模块PCB设计中应注意的问题。
关键词 数模转换模块 设计 PXI总线 A/D转换器 D/A转换器 体系结构 PCB
下载PDF
高精度、宽输出高压直流电源控制模块的设计
2
作者 孙晨晨 张强 +2 位作者 徐玮巍 高颂 赵华 《南京师范大学学报(工程技术版)》 CAS 2018年第3期69-73,共5页
针对经典的密里根油滴实验对直流电源的高精度、宽输出等要求,进行了高压直流电源中控制模块的硬软件设计.采用了双12 bit数模转换并联构成14 bit数模转换的方法,在不增加成本的基础上,提高了控制电压的分辨率.采用软件补偿的方法提高... 针对经典的密里根油滴实验对直流电源的高精度、宽输出等要求,进行了高压直流电源中控制模块的硬软件设计.采用了双12 bit数模转换并联构成14 bit数模转换的方法,在不增加成本的基础上,提高了控制电压的分辨率.采用软件补偿的方法提高控制精度,将实际控制电压的最大误差由0.12 V改善到了0.000 6 V.实验结果表明,高压直流电源的输出范围为-1 200~1 200 V,精度为±0.072 V. 展开更多
关键词 高压直流电源 控制模块 数模转换模块 软件修正
下载PDF
三菱模块上电跳闸问题分析与处理
3
作者 谭二惠 陈正石 《建筑机械》 2022年第11期129-132,共4页
三菱本地Q系列Q68DAVN数模转换模块上电时引起上端电流分配器频繁跳闸。经过测试,发现Q68DAVN数模转换模块上电瞬间冲击电流较大,与所选快跳型电流分配器保护形式冲突。以此对电流分配器的保护形式进行分析,并引入限流型电流分配器,最... 三菱本地Q系列Q68DAVN数模转换模块上电时引起上端电流分配器频繁跳闸。经过测试,发现Q68DAVN数模转换模块上电瞬间冲击电流较大,与所选快跳型电流分配器保护形式冲突。以此对电流分配器的保护形式进行分析,并引入限流型电流分配器,最终解决了跳闸问题。 展开更多
关键词 Q68DAVN数模转换模块 电流分配器 开关电源
下载PDF
卷径变化中的速度控制
4
作者 韩永刚 曾志清 毛虹 《橡塑技术与装备》 CAS 2003年第8期49-52,共4页
介绍了一种自动卷径测厚系统,包括电气配置,激光传感器设定,变频器设定,以及模数模块、数模模块的设定。给出了一部分程序梯形图及控制接线图。
关键词 可编程控制器 数模 数模模块 变频器 激光传感器
下载PDF
基于电力电子应用平台DSP通用板的设计 被引量:1
5
作者 姚念龙 裴晓泽 《微计算机信息》 北大核心 2006年第12Z期112-114,108,共4页
随着电力电子市场需求与日俱增,为了缩短电力电子硬件设计的开发时间,本文设计开发了DSP56F803通用板作为各种电力电子应用的硬件开发平台。为了增强它的应用灵活性,该通用板在扩展出DSP主要功能模块的同时,通过采用复杂可编程逻辑器件X... 随着电力电子市场需求与日俱增,为了缩短电力电子硬件设计的开发时间,本文设计开发了DSP56F803通用板作为各种电力电子应用的硬件开发平台。为了增强它的应用灵活性,该通用板在扩展出DSP主要功能模块的同时,通过采用复杂可编程逻辑器件XC95XL144实现各种保护逻辑以及输入输出口的扩展功能.DSP和CPLD综合利用作为通用板的核心是本文设计的主要特色。 展开更多
关键词 DSP56800 XC95XL144 脉宽调制模块 数模转换器模块
下载PDF
卷径变化中的速度控制
6
作者 韩永刚 曾志清 毛虹 《橡胶科技》 2004年第7期11-13,共3页
目前在一些自动化生产线中,存在卷径变化的问题。但是,很多情况下我们希望卷径在变,而线速度恒定。测量卷径有很多方法,下面我们介绍一种用激光传感器测量卷径,通过可编程控制器(PLC)运算来控制变频器,使线速度恒定的方法。电气配置如下... 目前在一些自动化生产线中,存在卷径变化的问题。但是,很多情况下我们希望卷径在变,而线速度恒定。测量卷径有很多方法,下面我们介绍一种用激光传感器测量卷径,通过可编程控制器(PLC)运算来控制变频器,使线速度恒定的方法。电气配置如下:可编程控制器:FX2N-64MR(三菱FX2N系列微型可编程控制器、继电器输出);模数模块:FX2N-4AD(三菱FX2N系列4通道模拟量转换成数字量特殊模块);数模模块:FX2N-4DA(三菱FX2N系列4通道数字量转换成模拟量特殊模块);变频器:VS-616G5A43P7(安川616G5系列,3相400V,3.7kW变频器); 展开更多
关键词 变频器 卷径 微型可编程控制器 模拟量转换 特殊模块 激光传感器 数模模块 数字量 自动化生产线 线速度
下载PDF
IPMC驱动材料控制系统的研制 被引量:3
7
作者 李玉秀 于敏 +2 位作者 何青松 宋林林 戴振东 《现代电子技术》 2011年第11期172-176,共5页
新型驱动材料IPMC具有驱动电压低,输出位移大,柔韧性好等优点,在仿生机器人和医疗仪器等微驱动领域有巨大的应用前景。为了满足IPMC驱动的需要和实现其便携性,为此进行了控制系统的研制。该控制系统由ATmega16L单片机控制模块、D/A数模... 新型驱动材料IPMC具有驱动电压低,输出位移大,柔韧性好等优点,在仿生机器人和医疗仪器等微驱动领域有巨大的应用前景。为了满足IPMC驱动的需要和实现其便携性,为此进行了控制系统的研制。该控制系统由ATmega16L单片机控制模块、D/A数模转换模块、扩大输出电流模块、电源模块、按键模块和LCD显示模块组成,能产生驱动IPMC双向摆动时所需的、具有高输出电流的双极性正弦波和方波,且其频率和幅值可调,同时还具有多通道分时控制功能。通过示波器对该控制系统的波形切换、调频和调幅功能进行的检测,也验证了其可行性。 展开更多
关键词 IPMC ATMEGA16L D/A数模转换模块 控制系统
下载PDF
电线电缆直流长时绝缘阻抗测试仪的研制 被引量:2
8
作者 李向男 王会永 +4 位作者 邢力 于钦先 郑海鹏 王彬 包大勇 《自动化仪表》 CAS 2018年第10期99-102,共4页
直流长时绝缘阻抗试验是IEC 60227-5:2011《额定电压450 V/750 V及以下聚氯乙烯绝缘电缆第5部分:软电缆(软线)》中,对户内装饰照明回路用软线新增的试验项目,主要考核户内装饰照明回路用软线绝缘在工作电压下长期运行的可靠程度。针对... 直流长时绝缘阻抗试验是IEC 60227-5:2011《额定电压450 V/750 V及以下聚氯乙烯绝缘电缆第5部分:软电缆(软线)》中,对户内装饰照明回路用软线新增的试验项目,主要考核户内装饰照明回路用软线绝缘在工作电压下长期运行的可靠程度。针对直流长时绝缘阻抗测试要求,研究分析了试验方法,确定了试验结果评定方法,设计并制作了电线电缆直流长时绝缘阻抗测试仪。该测试仪采用嵌入式单片机控制,数字波形发生器产生的正弦波经过二阶有源滤波器生成标准的正弦波;经线性功放及高压变换,输出标准的正弦波高压;正弦波高压经半波整流后,输出直流电压。测试仪体积小、结构简单、测量精度高,具有遥控启停和多路测试功能。应用测试仪,对户内装饰照明用软线进行了测试。测试结果表明,该测试仪能满足相关标准要求,可作为电线电缆长时直流阻抗测试的有效装置。 展开更多
关键词 电线电缆 数模转换模块 长时绝缘阻抗 继电器 滤波器
下载PDF
Mathematic Model of Unsteady Penetration Mass Transfer in Randomly Packed Hollow Fiber Membrane Module 被引量:2
9
作者 张秀莉 张泽廷 +1 位作者 张卫东 郝欣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期185-190,共6页
Based on the membrane-based absorption experiment of CO2 into water, shell-side flow distribution and mass transfer in a randomly packed hollow fiber module have been analyzed using subchannel model and unsteady penet... Based on the membrane-based absorption experiment of CO2 into water, shell-side flow distribution and mass transfer in a randomly packed hollow fiber module have been analyzed using subchannel model and unsteady penetration mass transfer theory. The cross section of module is subdivided into many small cells which contains only one hollow-fiber. The cross sectional area distribution of these cells is presented by the normal probability density distribution function. It has been obtained that there was a most serious non-ideal flow in shell side at moderate mean packing density, and the large amount of fluid flowed and transferred mass through a small number of large voids. Thus mass transfer process is dominated by the fluid through the larger void area. The mass transfer process in each cell is described by the unsteady penetration theory. The overall mass transfer coefficient equals to the probability addition of the mean mass transfer coefficient in each cell. The comparisons of the values calculated by the model established with the empirical correlations and the experimental data of this work have been done.The predicted overall mass transfer coefficients are in good agreement with experimental data. 展开更多
关键词 hollow fiber membrane module mass transfer membrane separation mathematic model
下载PDF
Research on parametric modeling and computing of multi-tower suspension bridge based on ANSYS 被引量:1
10
作者 Feng Zhaoxiang Zhao An +1 位作者 Song Jianyong Yang Yun 《Engineering Sciences》 EI 2012年第3期49-54,共6页
Based on FEM (finite element method) program ANSYS and the OpenGL graphics, this paper develops the parametric modeling module and the computing module of the multi-tower suspension bridge, the modules being embedded ... Based on FEM (finite element method) program ANSYS and the OpenGL graphics, this paper develops the parametric modeling module and the computing module of the multi-tower suspension bridge, the modules being embedded into the ANSYS system, and the parametric modeling module parameters can be entered by way of interface, which can fast establish a multi-tower suspension bridge model. Calculation module can establish load conditions for the features of road bridge and specifications, in which multiple conditions can be defined and solved automatically. Post-processing part of the solution also serves the results of the subtotals and selects the output, so that the results of the output and finishing work have become more convenient and easier, and also the results can be saved in word, excel and other different file types. 展开更多
关键词 ANSYS suspension bridge parametric modeling COMPUTING
下载PDF
基于FPGA的直接数字频率合成系统的仿真设计
11
作者 朱小祥 《软件导刊》 2008年第9期124-126,共3页
利用EDA系统工具的模拟功能对电路过程进行仿真,花费少,效率高。介绍了利用Multisim 9设计一基于FPGA的直接数字频率合成系统的全过程。
关键词 MULTISIM9 直接数字频率合成 波形存储器 数模转换模块 FPGA
下载PDF
Improved CFD modeling of full dissolution of alumina particles in aluminum electrolysis cells considering agglomerate formation 被引量:2
12
作者 Shui-qing ZHAN Ming-mei JIANG +1 位作者 Jun-feng WANG Jian-hong YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3579-3590,共12页
The full alumina dissolution process in aluminum electrolysis cells was investigated using an improved computational fluid dynamics(CFD)model based on the previous researches by consideration of agglomerate formation.... The full alumina dissolution process in aluminum electrolysis cells was investigated using an improved computational fluid dynamics(CFD)model based on the previous researches by consideration of agglomerate formation.The results show that the total mass of alumina agglomerate and its maximum size are mainly dependent on the feeding amount and increase with increasing it.Higher superheat can effectively inhibit the agglomerate formation and thus promote the full alumina dissolution behavior.The full alumina dissolution process mainly includes a fast stage and a slow stage,with an average dissolution rate of 17.24 kg/min and 1.53 kg/min,respectively.About 50%(mass percentage)of the total alumina particles,almost all of which are the well-dispersed alumina fine grains,dissolve within the fast dissolution stage of about 10 s.The maximum values of the average dissolution rate and final percentage of the cumulative dissolved alumina mass are obtained with a feeding amount of 1.8 kg for a superheat of 12℃.The formation of the alumina agglomerates and slow dissolution characteristics play a dominant role in the full dissolution of alumina particles. 展开更多
关键词 aluminum electrolysis alumina dissolution agglomerate formation theoretical modeling CFD modeling
下载PDF
Thermal Characteristics of Optoelectronic Modules with DIP and BGA Package
13
作者 GAO Hong-xia YU jian-zu XIE Yong-qi 《Semiconductor Photonics and Technology》 CAS 2006年第1期43-46,共4页
In order to meet the electrical and thermal performance requirements of current high performance optoelectronics, two package types with dual-in-line package(DIP) and ball grid array(BGA) for optoelectronics are model... In order to meet the electrical and thermal performance requirements of current high performance optoelectronics, two package types with dual-in-line package(DIP) and ball grid array(BGA) for optoelectronics are modeled and thermally simulated, their thermal characterizations are compared and discussed by using the temperature contours and the simulated heating characterization curves in free air and forced air ambient. The results show that BGA has superior inside and outside total performances, and has the promising future in the highly integrated optoelectronics. 展开更多
关键词 Thermal performance DIP BGA Heating characterization Numerical simulation
下载PDF
Design and Implementation of Data Acquisition System based on Linux Platform
14
作者 Yun Feng Youping Yan Nan Zuo 《International Journal of Technology Management》 2014年第7期75-77,共3页
This paper introduces the hardware structure and software design of data acquisition system based on embedded Linux. In order to improve the real-time response performance and the ability of multi task for system, usi... This paper introduces the hardware structure and software design of data acquisition system based on embedded Linux. In order to improve the real-time response performance and the ability of multi task for system, using ARM9 microprocessor technology in hardware, and transplant the Linux operating system, and the system reliability and scalability can be improved. The design makes full use of the characteristics of embedded Linux. The system software module have data acquisition module, data processing module, data communication module and data diagnostic module. The embedded Linux operating system is transplant into data acquisition system, that can accelerate the development of the system and convenient to future expansion functions, improve the observation data timeliness and accuracy, and can realize automation observation. 展开更多
关键词 Embedded Linux data acquisition system device driver
下载PDF
ANALYSIS OF MULTICONDUCTOR TRANSMISSION LINES USING THE MACCORMACK METHOD
15
作者 Dou Lei Wang Zhiquan 《Journal of Electronics(China)》 2006年第5期753-757,共5页
The MacCormack method is applied to the analysis of multiconductor transmission lines by intro- ducing a new technique that does not require decoupling. This method can be used to analyze a wide range of problems and ... The MacCormack method is applied to the analysis of multiconductor transmission lines by intro- ducing a new technique that does not require decoupling. This method can be used to analyze a wide range of problems and does not have to consider the matrix forms of distributed parameters. We have developed soft- ware named MacCormack Transmission Line Analyzer based on the proposed method. Numerical examples are presented to demonstrate the accuracy and efficiency of the method and illustrate its application to analyz- ing multiconductor transmission lines. 展开更多
关键词 Multiconductor transmission lines MacCormack method Numerical value simulation
下载PDF
基于三菱QPLC和Q62DA的轴承外圈沟磨床系统
16
作者 冯万寿 《机床电器》 2012年第3期34-35,共2页
利用三菱QPLC、Q62DA数模转换模块、中频变频器、辅以HMI人机界面、高刚度电主轴、交流伺服电机组成的控制系统,对数控轴承外圈沟磨床进行相对的恒线速磨削控制。
关键词 外圈沟磨床 数模转换模块 三菱QPLC 人机单元 恒线速磨削 中频变频器
下载PDF
Design and Implementation of English Teaching Management System Based on Web
17
作者 YAO Na 《International English Education Research》 2018年第1期58-60,共3页
In order to improve the intelligence of the English teaching management, so as to improve the English teaching resource scheduling and sharing ability, a design method of teaching management system is proposed based o... In order to improve the intelligence of the English teaching management, so as to improve the English teaching resource scheduling and sharing ability, a design method of teaching management system is proposed based on Web. The system adopts Web network architecture design, mainly it is divided into MUC main control module, database module, data management module and man-machine interaction module, Network management and online scheduling of English teaching resources are obtained based on C/S framework, data exchange of English teaching resources is realized on client side and server side, the control component of the English teaching resource distribution database uses MBM29LV400BC as the logic decoding controller. The intelligent algorithm is used to analyze the big data to realize the scheduling and access control of the English teaching management system resources. The test results show that the design of the English teaching management system has good resource scheduling and database construction ability, and the overall intelligence of the system is better. 展开更多
关键词 WEB English teaching Management system Software development
下载PDF
Collision Analysis of the Spar Upper Module Docking
18
作者 Yan Liu Liping Sun Chunlin Wu Guo Wei 《Journal of Marine Science and Application》 2014年第2期193-199,共7页
In order to assess the possible collision effect, a numerical simulation for the upper module and spar platlbrm docking at the speed of 0.2 m/s was conducted by using the software ANSYS/LS-DYNA, and the time history o... In order to assess the possible collision effect, a numerical simulation for the upper module and spar platlbrm docking at the speed of 0.2 m/s was conducted by using the software ANSYS/LS-DYNA, and the time history of the collision force, energy absorption and structural defonamtion during the collision was described. The purpose was to ensure that the platlbrm was safely put into operation. Furthermore, this paper analyzes different initial velocities and angles on the Von Mises stress and collision resultant force during the docking collision. The results of this paper showed that the docking could be conducted with higher security. The data in this paper can provide useful references for the determination of the upper module's offshore hoisting scheme and practical construction by contrasting the numerical simulation results of the parameters on the docking collision. 展开更多
关键词 spar upper module DOCKING offshore lifking collisionanalysis: spar plalIbrm- simulation analysis
下载PDF
Geometrical Langlands Ramifications and Differential Operators Classification by Coherent D-Modules in Field Theory 被引量:2
19
作者 Francisco Bulnes 《Journal of Mathematics and System Science》 2013年第10期491-507,共17页
Spaces of equivalence modulo a relation of congruence are constructed on field solutions to establish a theory of the universe that includes the theory QFT (Quantum Field theory), the SUSY (Super-symmetry theory) ... Spaces of equivalence modulo a relation of congruence are constructed on field solutions to establish a theory of the universe that includes the theory QFT (Quantum Field theory), the SUSY (Super-symmetry theory) and HST (heterotic string theory) using the sheaves correspondence of differential operators of the field equations and sheaves of coherent D - Modules [1]. The above mentioned correspondence use a Zuckerman functor that is a factor of the universal functor of derived sheaves of Harish-Chandra to the Langlands geometrical program in mirror symmetry [2, 3]. The obtained development includes complexes of D - modules of infinite dimension, generalizing for this way, the BRST-cohomology in this context. With it, the class of the integrable systems is extended in mathematical physics and the possibility of obtaining a general theory of integral transforms for the space - time (integral operator cohomology [4]), and with it the measurement of many of their observables [5]. Also tends a bridge to complete a classification of the differential operators for the different field equations using on the base of Verma modules that are classification spaces of SO(l, n + 1), where elements of the Lie algebra al(1, n + 1), are differential operators, of the equations in mathematical physics [1]. The cosmological problem that exists is to reduce the number of field equations that are resoluble under the same gauge field (Verma modules) and to extend the gauge solutions to other fields using the topological groups symmetries that define their interactions. This extension can be given by a global Langlands correspondence between the Hecke sheaves category on an adequate moduli stack and the holomorphic L G - bundles category with a special connection (Deligne connection). The corresponding D - modules may be viewed as sheaves of conformal blocks (or co-invariants) (images under a version of the Penrose transform [1, 6]) naturally arising in the framework of conformal field theory. 展开更多
关键词 Langlands correspondence Hecke sheaves category moduli stacks Verma modules generalized D-modules Vermamodule extensions
下载PDF
Research on marketing module and competitive strategy of E-Business Based on the VIP Website
20
作者 Zuo Teng Tian Shuge Chang Yue 《International English Education Research》 2015年第5期101-103,共3页
E-Business now is developing fast in China and the development of E-Business strategy is crucial as the right strategy can make the E-Business select the correct direction and get a better development. In this paper, ... E-Business now is developing fast in China and the development of E-Business strategy is crucial as the right strategy can make the E-Business select the correct direction and get a better development. In this paper, combined with SWOT parameters module, we will make a thorough research on the strategies used by Vip.eom from different angles. After this research, we will have a good understanding of strategies used by VIP website and learn to make better decisions in the e-business world. 展开更多
关键词 VIP Website SWOT Module Competitive Strategy
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部