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Proper modeling of switching windows leads to a better estimate of the noise-induced delay variations. In this paper, we propose a new non-iterative continuous switching model. The proposed new model employs an ordering technique combined with the principle of superposition of linear circuits. The principle of superposition considers the impact of aggressors one after the other. The ordering technique avoids convergence and multiple solution issues in many practical cases. Our model surpasses the accuracy of the traditional discrete model and the speed of fixed point iteration method. 相似文献
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Shenghan Zhou Houxiang Liu Bang Chen Wenkui Hou Xinpeng Ji Yue Zhang Wenbing Chang Yiyong Xiao 《Entropy (Basel, Switzerland)》2021,23(6)
The traditional sequential pattern mining method is carried out considering the whole time period and often ignores the sequential patterns that only occur in local time windows, as well as possible periodicity. Therefore, in order to overcome the limitations of traditional methods, this paper proposes status set sequential pattern mining with time windows (SSPMTW). In contrast to traditional methods, the item status is considered, and time windows, minimum confidence, minimum coverage, minimum factor set ratios and other constraints are added to mine more valuable rules in local time windows. The periodicity of these rules is also analyzed. According to the proposed method, this paper improves the Apriori algorithm, proposes the TW-Apriori algorithm, and explains the basic idea of the algorithm. Then, the feasibility, validity and efficiency of the proposed method and algorithm are verified by small-scale and large-scale examples. In a large-scale numerical example solution, the influence of various constraints on the mining results is analyzed. Finally, the solution results of SSPM and SSPMTW are compared and analyzed, and it is suggested that SSPMTW can excavate the laws existing in local time windows and analyze the periodicity of the laws, which solves the problem of SSPM ignoring the laws existing in local time windows and overcomes the limitations of traditional sequential pattern mining algorithms. In addition, the rules mined by SSPMTW reduce the entropy of the system. 相似文献
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《Electrophoresis》2017,38(3-4):452-459
A new detector, silvering detection window and in‐capillary optical fiber light‐emitting diode‐induced fluorescence detector (SDW‐ICOF‐LED‐IFD), is introduced for capillary electrophoresis (CE). The strategy of the work was that half surface of the detection window was coated with silver mirror, which could reflect the undetected fluorescence to the photomultiplier tube to be detected, consequently enhancing the detection sensitivity. Sulfonamides (SAs) are important antibiotics that achieved great applications in many fields. However, they pose a serious threat on the environment and human health when they enter into the environment. The SDW‐ICOF‐LED‐IFD‐CE system was used to determine fluorescein isothiocyanate (FITC)‐labeled sulfadoxine (SDM), sulfaguanidine (SGD) and sulfamonomethoxine sodium (SMM‐Na) in environmental water. The detection results obtained by the SDW‐ICOF‐LED‐IFD‐CE system were compared to those acquired by the CE with in‐capillary optical fiber light‐emitting diode‐induced fluorescence detection (ICOF‐LED‐IFD‐CE). The limits of detection (LODs) of SDW‐ICOF‐LED‐IFD‐CE and ICOF‐LED‐IFD‐CE were 1.0–2.0 nM and 2.5–7.7 nM (S/N = 3), respectively. The intraday (n = 6) and interday (n = 6) precision of migration time and corresponding peak area for both types of CE were all less than 0.86% and 3.68%, respectively. The accuracy of the proposed method was judged by employing standard addition method, and recoveries obtained were in the range of 92.5–102.9%. The results indicated that the sensitivity of the SDW‐ICOF‐LED‐IFD‐CE system was improved, and that its reproducibility and accuracy were satisfactory. It was successfully applied to analyze SAs in environmental water. 相似文献
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结合图像调焦系统的实际应用需求,提出一种基于OMAP(Open Multimedia Application Plant)处理器的图像调焦系统方案,给出了处理器与触摸显示屏的接口硬件设计,分析了在Linux系统下的接口驱动开发,讨论了实际应用中存在的图像分辨率变换及触点窗口形成两个关键问题,将输入的图像数据及对焦窗口成比例显示在液晶屏上。在自动选择的对焦窗口不满足要求时,使用触摸屏来重新调整对焦窗口,从而实现人工参与对焦窗口的快速选择及调整,满足了特定领域对图像调焦系统的特殊要求。 相似文献
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