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61.
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 总被引:1,自引:0,他引:1
陈锡尧 《武汉体育学院学报》2005,39(8):17-20
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。 相似文献
62.
该文介绍了在工业控制系统软件设计中上位计算机与PLC(可编程序控制器)及工业仪表等设备通过串行方式进行通信的基本设计原理,硬件要求,实现方法,以及利用CB6.0实现该过程的应用实例. 相似文献
63.
黄河 《广西广播电视大学学报》2006,17(4):20-24
网络的普及推动了视频会议系统的推广。本文首先简要介绍了视频会议的发展情况,阐述视频会议的国际标准H.323协议的发展、标准结构、系统组成和使用MCU创建视频会议的过程,并以POLYCOM公司视频会议产品为例,结合广西广播电视大学双向视频教学系统,介绍视频会议系统在远程教育中的应用。 相似文献
64.
Modelling and analysis of a basilica under earthquake loading 总被引:1,自引:0,他引:1
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. 相似文献
65.
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. 相似文献
66.
67.
本文介绍了PIC单片机的特点,以及利用该芯片、移位寄存器74LS164和阵列电路控制继电器的开关闭合,来实现对大量外部设备的控制。该方法的实现可以有效地节省大量的单片机I/O引脚的使用个数,特别是在一些要实现的功能较多的工程中,效果更为显著。 相似文献
68.
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。 相似文献
69.
Christian Köhler 《Research Policy》2012,41(8):1344-1356
The shift toward more open and interconnected innovation activities has been a major topic in recent academic and practitioner discussions. Firms must connect their in-house R&D activities with external partners, such as leading customers or universities, to increase the effectiveness of their innovation activities. Hence, management needs to define where to search for valuable knowledge in its environment. In this paper we argue that knowledge search has to reflect the heterogeneity of various knowledge sources with regard to the knowledge they can provide and how these sources can be activated. We hypothesize that search strategies driven by science, suppliers and the product market will contribute differently to innovation success with new-to-market versus imitated products. Moreover, we explore the effect of these types of knowledge search within different sectoral patterns of innovation. Our empirical analysis rests on a sample of almost 5000 firms from five Western European countries. The results support our hypotheses and highlight the potentials and shortcomings of different types of knowledge search. 相似文献
70.
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。 相似文献