由LM331构成单片机V/F精密数据采集电路

本文介绍了一种电压频率转换器构成串行模数转换器的应用,包括单片计算机与其接口的电路和高精度频率测量程序设计方法。使用少量线路构成V/F数据采集通道,程序控制电路接口,实现模拟信号高精度转换为计算机要求的数字信号。     

F1中国站大奖赛对长江三角洲经济和社会影响的分析

通过对近年来一级方程式赛车大奖赛在欧洲及亚太国家举办中每年给举办国带来的巨大经济收益的解读。就即将在我国上海举办的F1中国站大奖赛对我国长三角地区经济和社会发展带来的拉动与影响进行了前瞻性的分析。指出F1中国站的举办必将给我国长三角地区的社会和经济发展带来巨大的影响。     

F1中国大奖赛在我国的消费需求及其对地区经济影响的调查研究

就F1赛车对上海及其周边地区的影响作用,通过新秦网对全国范围内18岁以上的4 939人进行了问卷调查。调查结果表明,虽然人们对于赛车文化的理解尚未深入,但是,赛车运动在中国的发展还是很有潜力的。研究认为,F1上海站赛事将会促进上海及其周边地区消费水平的提高,对促进上海及其周边地区的区域经济发展具有巨大的影响作用。     

无刷直流电动机的无位置传感器数字控制系统设计方案研究

本文提出了采用DPS数字信号处理器并辅以单片机的无刷直流电动机的无位置传感器数字控制系统设计方案.该方案既可降低电路的复杂性,又可获得较高的性价比.     

Modelling and analysis of a basilica under earthquake loading

In this paper a basilica-type church is analysed in order to assess its structural behaviour and seismic vulnerability. For this purpose, an effective two-step procedure has been used, consisting of: (a) 3D static and dynamic linear analyses of the structural complex, and (b) 2D nonlinear push-over analysis of the single macro-elements. The results obtained through push-over analyses have been compared to the collapse loads derived from limit analysis, proving the ability of finite element (F.E.) nonlinear model to provide reliable simulation of the actual response of masonry elements. Then, the strength demand on each single structural macro-elements, resulting from the 3D linear analyses, has been compared to the macro-element ultimate strength capacity. The comparison demand vs. capacity has been carried out for all transversal and longitudinal macro-elements of the church, allowing a direct, though approximate, assessment of the seismic safety level of the church. The comparison demand vs. capacity confirms the susceptibility of this type of buildings to extensive damage and possibly to collapse, as frequently observed. The insertion of rigid diaphragms, which represents a widely used retrofit technique, has also been investigated; such intervention triggers concentration of strength demand in the stiffest macro-elements, so that the seismic capacity of the building is not necessarily increased.     

Racial similarity as a moderator variable in the perception of leader behavior and control

This study compared leader behavior ratings of black and white Army infantry squad members serving in squads led either by black or white leaders. One black and one white squad member, chosen at random from each of 34 racially mixed squads, rated their leader's Consideration and Initiation of Structure behaviors (Stogdill, 1963), and their leader's behavior relevant to French and Raven's (1959) five bases of social power. In general, it was found that members who were of the same race as their leader rated him as significantly less likely to use punishment-related behaviors than did members who were of a different race than their leader. However, same-race members did not rate their leader's considerate or structuring behavior differently than did different-race members. The overall pattern of findings were discussed in terms of the leaders' implicit reliance on their punishment power to obtain compliance from different-race subordinates.     

F4方程式摩托艇比赛电子计时系统的设计

为了提高摩托艇比赛计时系统的精确性和高效性,设计了一种电子计时系统,系统以单片机AT89C51为微控制单元,通过激光传感器,对激光进行感知,并将激光信号转化成电信号传递给单片机,系统设计了两种模式,一种是排位赛模式,第二种是竞速赛模式,分别编写了两套程序,单片机根据程序可以准确执行指令,实验表明,次电子计时系统大大提高了裁判的准确度,以及成绩编排效率,而且完全可以符合现有摩托艇的比赛规则。     

一种基于C8051F060的声波信号采集系统的设计

为了监测某区域某频率段内声波信号的强弱,提出一种以C8051F060为控制核心的声波信号采集系统的设计方案。采用压力场声波传感器将可识别的声波信号转换为适当幅度的电信号,该信号经过由程控滤波器地处理后直接送至带高速ADC的单片机进行处理,最后以SYG2401281图形点阵液晶为显示器件实现声波信号的实时显示。     

基于TMS320F2812的CANopen协议的通信实现

CANopen是一种开放的现场总线协议,是欧洲嵌入式工业控制网络的主要标准协议.在分析CANopen协议的对象字典、设备模型和通信对象等的基础上,采用CANopen协议的子协议DS301实现了基于CAN总线的TMS320F2812与主控模拟调试软件之间的通讯,并通过测试验证了通讯过程中信息传递的正确性和可靠性.     

基于VPC3+C的Profibus-DP智能从站设计

从开发的角度介绍了VPC3+C芯片的主要功能和单片机C8051F020以及软硬件设计的主要思想,分析了Profibus-DP从站的状态机,并介绍了从站与主站通讯所需的GSD文件.