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排序方式: 共有1433条查询结果,搜索用时 15 毫秒
1.
Determination of Discrete Spectrum in a Random Field   总被引:1,自引:0,他引:1  
We consider a two dimensional frequency model in a random field, which can be used to model textures and also has wide applications in Statistical Signal Processing. First we consider the usual least squares estimators and obtain the consistency and the asymptotic distribution of the least squares estimators. Next we consider an estimator, which can be obtained by maximizing the periodogram function. It is observed that the least squares estimators and the estimators obtained by maximizing the periodogram function are asymptotically equivalent. Some numerical experiments are performed to see how the results work for finite samples. We apply our results on simulated textures to observe how the different estimators perform in estimating the true textures from a noisy data.  相似文献   
2.
This paper investigates the dividend signaling hypothesis, described here as the relationship between dividend changes and future earnings performance. We find that managers pursue different patterns in UK from that in US when making dividend policy. A positive and significant association between dividend changes and the growth of future earnings is observed in the immediately following year after dividend announced There isn't significant link in the longer future. These phenomena are caused by managers' near-eyesight in UK market. In addition, an interesting finding is that dividend decreases have larger negative influence on earnings growth than positive impact on earnings prospects of dividend increases. This is consistent with the infrequent occurrence of dividend reduction.  相似文献   
3.
本文介绍了直接数字频率合成(DDS)芯片AD9852与可编程门阵列(FPGA)相结合采用数字方法实现中频线性相位调制(PM)及试验结果。  相似文献   
4.
介绍了小型化、通用化和实时信号处理要求下,雷达接收机的通用数据采集处理硬件平台。采用Xilinx公司最新平台级FPGA产品Spartan-3系列芯片构建平台,并实现其中的FFT于模块。试验表明,处理精度和速度都满足要求,为该方案的可行性和后续模块的实现提供了依据。  相似文献   
5.
Hall and Miles (1990) suggest an approach of estimating default probabilities of banks using stock market information, and in this paper we apply an aggregated version of their approach to banking sectors around the world in both developed and emerging economies. We study the market’s assessment of the probability of systemic banking crises world wide over the last decade, including the Asian crisis 1997–1998. In addition, we investigate whether there is a relationship between the failure probability and institutional features of the actual banking sector. The quality of governance and the degree of law and order in a country is found to be significantly negatively related to the market based failure probabilities as is an explicit deposit insurance during periods of crisis.  相似文献   
6.
文中通过回顾企业风险预警管理相关文献,分析了物流企业风险形成主要影响因素,并结合物流企业运营特征,建立基于顾客导向的物流企业预警指标体系,运用灰关联分析方法评价物流企业顾客满意度,对物流企业的风险进行预警。  相似文献   
7.
This paper examines funding issues for UK Technology-based Small Firms (TBSFs). TBSFs are the cry of today and UK government like other countries is trying to increase the mass of TBSFs by various means. However, it is reported that TBSFs face many impediments to their successful development. Finance is believed as the main barrier at the early stages of TBSFs development. This paper is attempting to follow up and report if the funding situation for UK TBSFs has improved. The findings reported in this paper suggest that nearly 80% sample firms were finance constrained at the early stages of business development.  相似文献   
8.
介绍了基于Web和数据仓库的房地产市场预警预报系统的体系结构,探索设计了房地产市场预警预报系统的技术与方法,并提出了基于Web和数据仓库的房地产市场预警预报系统的完整解决方案。  相似文献   
9.
多功能信号发生器的设计   总被引:1,自引:0,他引:1  
以MAX038集成芯片为核心,采用MCU微处理器控制程控继电器和数字电位器,设计了多功能信号发生器。能够输出方波、正弦波、三角波和AM信号,并能实现频段选择和频段内频率微调。  相似文献   
10.
在多分辨率分析的基础上,采用二进正交小波变换对电力系统暂态信号进行了分析.将信号分解成许多细节部分和平滑部分(分别是信号的高频部分和细节部分),通过分析信号在各个尺度下的细节部分,从而可以对暂态信号的时域和频域进行定位.实验结果证实了方法的有效性.  相似文献   
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