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1.
一种自适应斜坡补偿电路   总被引:1,自引:0,他引:1  
基于CMOS工艺设计了一种能够自动调节补偿斜率的斜坡补偿电路。该电路可以跟随输入和输出信号的变化,相应地给出适当的斜坡补偿量,不仅使得峰值电流模式BOOST变换器可以稳定工作,而且可以避免补偿不当的现象,保证变换器有足够快的瞬态响应。仿真结果表明该电路产生的斜坡补偿信号的精度可以达到83%以上。  相似文献   
2.
介绍了潜在成长模型的发展、类型和内容,通过分析、归纳、整理等,比较了潜在成长模型与传统t检验、方差分析、回归分析的差别,探讨了潜在成长模型研究设计的要求,通过台湾棒球职业球员薪酬成长模型说明。利用文献调查法,分析了LGM潜在成长模型在体育运动领域中应用的概况,举例说明体育运动领域应用LGM的情况,证实了未来潜在成长模型会在体育科学领域逐渐受到重视并得到快速发展。  相似文献   
3.
将数字摄影测量技术应用于边坡位移自动监测。在边坡上布设固定标志点,将非量测数码相机置于边坡正面,运用程序控制相机间隔一定时间对边坡进行拍摄。对拍摄图像预处理后使用圆心亚像素识别算法确定测点亚像素位置。根据标志初始实际距离与初始相片像素距离建立物象比例,对比各次识别结果得到各测点实际的相对位移。运用GPS技术和计算机技术,本系统可实现数据交换、控制指令发送和预警的适时监控。本系统采用非量测数码相机,相对于传统边坡检测方法具有成本低,精度高,需要人工干预少等优点,现场试验50 m距离识别精度达到3 mm,取得较好效果,可以作为大量边坡自动化监测的有效手段。  相似文献   
4.
Good estimation of the slopes of the mixture response function may be important as well as estimation of mean mixture response. It is possible to evaluate and compare several mixture designs with respect to the slope. A graphical method is proposed that allows us to evaluate a given design's support for the fitted model in terms of slope variance. We can plot variances of slopes along Cox direction or axial direction according to existence of restriction of simplex region or not when comparing several different mixture designs.  相似文献   
5.
Three tables for selection of single sampling plans with any one of the following combinations of entry parameters are givens.

1) the indifference quality level and the average outgoing quality limit.

2) the indifference quality level with relative slope of the OC curve at that quality leve land.

3) the quality level corresponding to the inflection point with relative slope of the OC curve at that quality level.

A table enabling the transition from one set of parameters to match the OC curve of other similar sets is also given.  相似文献   
6.
针对大坡度桥梁预制梁架设,以阿尔及利亚东西高速公路(中段)18公里桥为例,在原有架桥机基础上进行了改装设计,并采取其它工程措施保证了架梁的速度、质量和安全,使大坡度T梁架设工作得以顺利完成。  相似文献   
7.
固定资产的分类投入在不同时期从不同程度上影响着区域的经济增长。以哈尔滨市1978—2005年的固定资产及其分类投入和区域生产总值数据作为研究基础,运用灰色斜率关联度作为计算工具,克服了邓氏关联度需要用参考点,在计算时要对原始数据进行标准化处理,且容易出现只有一个序列起作用的情况,对哈尔滨市固定资产行业(部门)的分类投入与区域生产总值的动态经济依存关系和经济结构进行了详细地剖析,从新的角度得出基本结论:基础设施行业(部门)投资对经济发展起着重要作用并逐步增强,但是工业部门对经济发展的作用仍然处在首位,同时哈尔滨市的服务业对经济发展的作用并没有发挥出来。  相似文献   
8.
应用宏观地质分析方法,分析了影响船闸高边坡岩体稳定的内、外在因素,并对其稳定性进行了评价,提出了工程施工和工程处理应注意的主要问题。  相似文献   
9.
Tax practitioners play a crucial role in the degree of taxpayers’ compliance – a role that has increased as tax systems worldwide have become more complex. However, little is known about tax authorities’ impact on taxpayers’ decisions to employ tax practitioners. Based on earlier research on motivations to employ a tax practitioner and the extended slippery slope framework of tax compliance, we conducted two studies which provide some answers. A survey study – comprising a representative sample of 500 Austrian self-employed taxpayers – revealed that financial gain is not the most important reason to employ a tax practitioner but instead the motivation to avoid problems with the tax authorities. Related to that, we also find that taxpayers’ perception of tax authorities wielding coercive power motivates them to employ tax practitioners. In the interview study with 33 self-employed taxpayers and 30 tax auditors, taxpayers indicated that they sought to avoid contact with tax officers by employing tax practitioners. This finding was supported by tax officers who reported preferring interaction with tax practitioners over direct contact with taxpayers. The two studies point to the complex relationship between taxpayers, tax authorities and tax practitioners, and allow the drawing of theoretical and practical implications.  相似文献   
10.
For several independent multivariate bioassays performed at different laboratories or locations, the problem of testing the homogeneity of the relative potencies is addressed, assuming the usual slope‐ratio or parallel line assay model. When the homogeneity hypothesis holds, interval estimation of the common relative potency is also addressed. These problems have been investigated in the literature using likelihood‐based methods, under the assumption of a common covariance matrix across the different studies. This assumption is relaxed in this investigation. Numerical results show that the usual likelihood‐based procedures are inaccurate for both of the above problems, in terms of providing inflated type I error probabilities for the homogeneity test, and providing coverage probabilities below the nominal level for the interval estimation of the common relative potency, unless the sample sizes are large, as expected. Correction based on small sample asymptotics is investigated in this article, and this provides significantly more accurate results in the small sample scenario. The results are also illustrated with examples.  相似文献   
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