关键词： 数学形态学   谐波   自适应算法   多结构元素   形态滤波器  

摘要： 电网谐波的危害日益严重,采用准确快速的谐波检测法能有效控制和预防电力谐波给电网带来的威胁,对现有的多种谐波检测方法的速度和准确性进行综合比较后,文章采用数学形态学滤波与自适应算法相结合的谐波检测的优化方法,通过自适应结构来选取不同的结构元素,使得形态滤波器能更好地适应实际电网中的需求.采用Matlab/simulink软件进行仿真,提取出信号的主要结构特征,与基波信号更相近,准确度更高,速度更快.

关键词： 排序问题   范数学习   贪婪学习  

摘要： 为了更直接地定义点对间的序关系,引入了排序问题的范数学习模型。该模型利用样本空间中的范数类描述样本间的不同序关系。借鉴范数学习的思想,得到了有效处理此类排序学习问题的贪婪学习算法。实验结果表明,此类算法排序效果良好。

关键词： Canny算子   数学形态学   迭代最佳阈值分割算法   禽蛋   边缘检测  

摘要： 针对传统的单一Canny算子进行禽蛋边缘检测存在抗噪能力弱、假边缘等问题,讨论了一种基于数学形态学与Canny算子相结合的禽蛋图像边缘提取方法。基于数学形态学,采用迭代最佳阈值分割算法,得到阈值分割的图像,对其求反后运用腐蚀算法,得到最终待检测的图像。再基于Canny算子进行禽蛋边缘提取。试验结果表明,该方法具有边缘定位能准确、连通性畅、抑制噪声能力强,实时性快等优点。

关键词： Cholesterol biosynthesis model   Biological feedback mechanisms   Systems biology   Functional genomics  

摘要： Elevated levels of cholesterol are known to be a risk factor for cardiovascular diseases. As a result, several treatment strategies and drugs have been developed to control these elevated cholesterol levels, but they are not always successful. Statins are now the most widely used cholesterol-lowering drugs;however, not all the mechanisms of their action are understood and this can sometimes lead to adverse effects. A dynamic mathematical model of the cholesterol biosynthesis network was developed with aim to understand the key mechanisms of cholesterol biosynthesis. In this article we show that in spite of a serious lack of experimental data, the model can be used to study the concepts of possible mechanisms of cholesterol biosynthesis and drug interactions. If only steady-state data is used for the model's identification, the model can predict the steady-state relations after perturbation correctly, while the dynamical properties are not necessarily related to the real system. The control mechanism for the cholesterol levels through the SREBF-2 transcription factor was identified as the PI control algorithm. The comparison of model simulations and performed biological experiments indicated that the substances LK-980 and Atorvastatin most likely trigger the same indirect mechanism of cholesterol biosynthesis control, although they interact with the network in different ways. (C) 2011 Elsevier B.V. All rights reserved.

关键词： Algorithms   Applied mathematics   Biology   Chronic kidney disease   Economics   Mathematical computing   Mathematical optimization   Mathematics   Medicine   Nephrology   Operations research   Population biology   Research Article   Social and behavioral sciences  

摘要： Background: The equations provide a rapid and low-cost method of evaluating glomerular filtration rate (GFR). Previous studies indicated that the Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease-Epidemiology (CKD-EPI) and MacIsaac equations need further modification for application in Chinese population. Thus, this study was designed to modify the three equations, and compare the diagnostic accuracy of the equations modified before and after. Methodology: With the use of (99) Tc-m-DTPA renal dynamic imaging as the reference GFR (rGFR), the MDRD, CKD-EPI and MacIsaac equations were modified by two mathematical algorithms: the hill-climbing and the simulated-annealing algorithms. Results: A total of 703 Chinese subjects were recruited, with the average rGFR 77.14 +/- 25.93 ml/min. The entire modification process was based on a random sample of 80% of subjects in each GFR level as a training sample set, the rest of 20% of subjects as a validation sample set. After modification, the three equations performed significant improvement in slop, intercept, correlated coefficient, root mean square error (RMSE), total deviation index (TDI), and the proportion of estimated GFR (eGFR) within 10% and 30% deviation of rGFR (P-10 and P-30). Of the three modified equations, the modified CKD-EPI equation showed the best accuracy. Conclusions: Mathematical algorithms could be a considerable tool to modify the GFR equations. Accuracy of all the three modified equations was significantly improved in which the modified CKD-EPI equation could be the optimal one.

关键词： Artificial neural network   carbon dioxide   equations of state   genetic algorithm   mixture combining rules   water  

摘要： The solubility of carbon dioxide in water is measured at 278.15348.15K and 0.11MPa. The experimental data are compared with those obtained from equations of state such as van der Waals, Redlikh-Kwong, Soave- Redlikh-Kwong, Peng-Robinson coupled with two mixing rules van der Waals and Wong Sandler equations. Also, the solubility of carbon dioxide in water is modeled using the artificial neural network system and optimized with genetic algorithm method. The results show that the artificial neural network system can accurately predict the solubility of carbon dioxide in water than the other equations of state.

关键词： 道路容量限制   多配送中心   选址   数学模型   算法  

摘要： 文章研究了带道路容量限制的多配送中心选址问题,在综合考虑货物周转费用、运输费用、配送中心年固定费用的前提下,根据实际情况引入了运输道路容量限制,以总费用最低为目标建立了该问题的整数线性规划模型。然后给出了求解该模型的精确算法,又根据贪婪思想设计了求解该问题的启发式算法,并利用具体的实例进行了模拟计算,结果显示,其模型及算法具有很好的效果。

关键词： 工业CT图像   数学形态学   边缘检测   ImageJ软件  

摘要： 图像边缘检测是工业CT图像处理中一项十分重要的工作和预处理步骤,图像的最终处理结果取决于边缘检测的优劣程度。首先介绍了几种经典的图像边缘检测方法,并用这几种算法对工业CT图像进行了计算机仿真。通过对仿真结果的对比和分析,提出了基于数学形态学和图像融合相结合的图像边缘检测算法MDY并在ImageJ软件上编程实现。实验结果表明,该算法能够有效地抑制噪声,完整地检测边缘,且优于其他传统边缘检测算法。

关键词： 子午流注针法   干支   数学公式推算  

摘要： 子午流注针法是根据人体气血流注的盛衰开阖结合阴阳五行、天干地支、脏腑经络等来逐日按时开穴的一种针刺方法。干支是＂天干＂和＂地支＂的合称,天干始于甲,地支始于子,干支相合,六十环周。只有准确的推算出年、月、日、时的干支,

关键词： 数学函数   精度控制   浮点运算   算法实现  

摘要： 本文在函数相关的迭代算法以及级数法的基础上,总结出了一种逼近、归纳以及重建的函数相关的改进算法,使其可以很好地满足浮点运算相关的要求。并且通过一定的测试,对优化算法的优越性进行了证明,与此同时,针对基础数学库进行实现方法相关的研究,可以对高性能计算所需求的性能以及精度更加有效地满足。