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201.
This paper expatiates on the bus structure and develop the bus mode Multi-Channel Analyzer (MCA). The nucleus of this MCA is the PC/104 embedded computer, and it introduces the bus communication to realize system and data communication. It may realize data collecting and showing in the field, because the bus mode is rapid. At first, on the hardware we introduce CMOS components, this reduces power, volume and weight. These make it adapts to use in the field; besides, on the software we adopt C and assembly language to program in order to improve conversion speed. At the same time, single-task DOS operating system is infroduced, which makes the software run more steadily, operate more simply. By means of testing on the spot it can normally work, so it suitable to work in the field. 相似文献
202.
Apache Struts is one of the most popular open source framework for Web applications and developments using MVC Model2 architectural pattern. Using the Information Technology to improve the efficiency of education service is emergent. The aim of this paper is to demonstrate the design and realization of a platform system software based on Apache Struts framework. By briefly analyzing the extra requirement in higher education service, an architecture based on MVC design pattern is presented. Some core technologies used in the platform system software, such as Struts Tiles and Struts Menu etc, are proposed in details by the end. Because of its struts-based fundamental architecture and running mechanism, the platform system software made a certain performance advantage and largely reduced the developing period. 相似文献
203.
为探讨粮食增产、农民增收的有效途径,结合国家农业部在永修实施的"水稻综合生产能力科技提升试点行动"项目,选择推广7项节本增效综合配套技术,从而使项目核心区比非项目区增产12.8%,幅射区比非项目区增产5.8%,取得了较好的经济、社会和生态效益. 相似文献
204.
Using non-parameter test and multinomial logit regression, this paper studies the dividend policy and behavior empirically. The results show that the change of the earnings of firms affects their dividend policy. When the EPS of the firms increase, the probability of choosing not to pay cash dividend is maximal, yet when the EPS of the firms decrease, many firms choose not to pay cash dividend or choose to increase DPS, so that the information that the relevant firms have great expectation is transmitted to the market. Furthermore, this paper also finds that the successiveness of the dividend policy of the listed firms in China is not good. 相似文献
205.
Zhao Changfu Feng Xiangui Li Yulan 《保鲜与加工》1991,(6):115-118
Calculations and analyses are made with the CVDA, IIW, JWES standards for the strength and welding defects of two spherical tanks of natural gas in CHONG QING. The results of the analyses indecate that though there are some problems with the welding quality in these tanks, they may still be used with the desingned presure. Now the formal working of these two spherical thanks has verified of the validity the calculations and analyses. 相似文献
206.
The relationship of investors and venture capitalists is an important part in venture capital. Based on asymmetric information, this paper analyzes the principal agent relationship between investors and venture capitalists with game theory. And this paper mainly discusses the choosing, controlling and incentive problem. It suggests that only the capable and self confident venture capitalists could accept the terms of the limited partnership. It also indicates that recompense mechanism which holds the interest of investors and that of venture capitalists tightly is the center of the limited partnership. Rate of yield is the key of recompense mechanism, it not only reflects the incentive on venture capitalists, also reflects the share of risk between investors and venture capitalists. At last, the market credit play an important role in venture capital. 相似文献
207.
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209.
Feng Hailiang Wu Junliang 《保鲜与加工》1997,(6):108-113
Some conceptions of stable quaternion matrices and some judging criteria are given.The Robrach theorem,Taussky theorem,Ostrowski Schneider theorem and Gerschgorin theorem are generalized to quaternion field.The conclusion about two quaternion matrices,i.e.,inferior positive matrices are unstable,interior negative matrices are stable and some other results are pointed out. 相似文献
210.
基于单台强震数据软厚场地地震反应不确定性分析 总被引:1,自引:0,他引:1
选取新西兰Canterbury地区12个强震台站及2010—2012年间的台站584条记录,以浅硬场地LPCC作为参考台站,系统分析Christchurch市区软厚场地地震效应(即场地放大函数)的不确定性及地震动强度、震级、震源距及震源方位角等因素对场地放大函数不确定性的影响规律。分析结果发现:1)地震动强度水平对场地放大函数均值影响较小,仅在长周期(如大于1.0 s)段趋于增大场地的放大效应;以不同地震动强度值进行分组,地震动强度大于0.6 m/s 2的分组场地放大函数标准差显著高于地震动强度小于0.6 m/s 2分组,特别是地震动强度大于1.0 m/s 2时场地放大函数标准差最大,反映了场地土层非线性提高场地地震效应的不确定性;2)地震震级对场地放大函数不确定性影响小,不同地震震级分组场地放大函数均值及标准差的表现基本相当;3)震源距是场地地震反应不确定性的一个重要因素,震源距小于5 km时场地放大函数的标准差明显大于其它情况,即震源距越小地震反应不确定性越大;4)场地放大函数不确定性与震源方位角的选取基本无关,即选取不同的震源方位角场地放大函数标准差无明显差别。 相似文献