免疫算法在双闭环直流调速系统中的应用

文中对双闭环直流调速系统控制器的选择进行了分析,并借鉴免疫算法强大的寻优能力,提出了基于免疫算法的调速系统控制器参数整定方法.为了分析比较,实际应用中采用了三种控制器参数整定方法,比较结果说明,免疫算法在调速系统控制器参数整定中的应用是更加有效的.通过在单晶炉拉晶过程的应用,证明该方法可行性和正确性.     

EGFAFS: A Novel Feature Selection Algorithm Based on Explosion Gravitation Field Algorithm

Feature selection (FS) is a vital step in data mining and machine learning, especially for analyzing the data in high-dimensional feature space. Gene expression data usually consist of a few samples characterized by high-dimensional feature space. As a result, they are not suitable to be processed by simple methods, such as the filter-based method. In this study, we propose a novel feature selection algorithm based on the Explosion Gravitation Field Algorithm, called EGFAFS. To reduce the dimensions of the feature space to acceptable dimensions, we constructed a recommended feature pool by a series of Random Forests based on the Gini index. Furthermore, by paying more attention to the features in the recommended feature pool, we can find the best subset more efficiently. To verify the performance of EGFAFS for FS, we tested EGFAFS on eight gene expression datasets compared with four heuristic-based FS methods (GA, PSO, SA, and DE) and four other FS methods (Boruta, HSICLasso, DNN-FS, and EGSG). The results show that EGFAFS has better performance for FS on gene expression data in terms of evaluation metrics, having more than the other eight FS algorithms. The genes selected by EGFAGS play an essential role in the differential co-expression network and some biological functions further demonstrate the success of EGFAFS for solving FS problems on gene expression data.     

基于光谱曲线形态的高光谱影像检索方法研究

随着传感器技术、数据通讯技术的飞速发展,利用各种机载和星载传感器,己经获取到各种不同的海量遥感影像数据。巨大的数据量带来了数据存储和管理的问题,如何实现从海量影像数据中检索出我们所需要的信息显得十分迫切。影像检索最早由Chang于1980年提出,是对传统信息检索的扩展。针对海量遥感影像高效检索的需求和高光谱遥感影像波段数目多的特点,分析了影像检索中的影像距离函数和相似性度量问题,基于经典的曲线简化Douglas-Peucke算法(简称DP算法)提取光谱曲线的形态特征,利用“提取特征”的思想,提出了基于DP算法的光谱曲线和影像检索(简称DPSR)方法,将光谱形态特征应用于影像检索当中。DPSR利用光谱曲线上的特征点,减小了计算量,实现了有效地匹配和检索,适合高光谱遥感影像的光谱检索。文章选择了OMISI高光谱数据的四种易混分地类进行了相似性度量的对比实验。通过与常规的分析方法光谱角匹配(SAM)、光谱信息散度(SID)的对比可以看到,DPSR在较少计算量的情况下能保持较高的计算精度,提供了一种新的影像光谱高效检索方法。此外,文章还提出了尚待进一步研究的问题。     

一种求解混合整数非线性规划问题的演化算法--搜索空间自动收缩法

提出一种求解混合整数非线性规划问题的新的演化算法 -搜索空间自动收缩法 (ACSSOS) .在这种算法中 ,演化算法既用来定位最优解区域 ,实现搜索空间自动向全局最优解收缩 ,又用来最终求得最优解 .由于在遗传算子中引用了舍入操作 ,它不仅可用来求解混合非线性整数规划问题 ,也可求解纯整型或纯实型变量非线性函数优化问题 .数值试验结果表明本文的算法在解的质量、稳定性和收敛速度等方面优于一般的演化算法 .     

高阶常微分方程的动态演化建模

提出了采用高阶常微分方程模型代替传统时序分析中所用的ARMA模型来实现一维时间序列的建模和预报．设计的将遗传程序设计与遗传算法相嵌套的动态演化建模算法,用遗传程序设计优化模型结构,以遗传算法优化模型参数,边收集数据边建模边预报,首次成功地实现了时间序列实时预报的程序自动化．两个时间序列的应用实例表明采用此算法可获得较好的实时预报效果．     

基于无约束非线性优化算法的光强自相关函数拟合

在光子相关光谱(PCS)颗粒测量技术中非线性累积反演方法是一种重要的算法。采用无约束非线性优化算法对反演过程中相关曲线的拟合问题进行了分析和研究, 实现了从任意初始值开始获取最优非线性拟合解, 并给出了算法的实现步骤。采用此方法对50 nm, 100 nm, 200 nm和500 nm的标准聚苯乙烯乳胶颗粒的实测光强自相关函数数据进行了拟合, 并反演了颗粒粒径, 与其他曲线拟合算法相比, 本算法不但对初始值的依赖性小, 而且得到的颗粒粒径更接近乳胶颗粒的标称直径, 测量误差更小。     

A primitive-variable Riemann method for solution of the shallow water equations with wetting and drying

A Riemann flux that uses primitive variables rather than conserved variables is developed for the shallow water equations with nonuniform bathymetry. This primitive-variable flux is both conservative and well behaved at zero depth. The unstructured finite-volume discretization used is suitable for highly nonuniform grids that provide resolution of complex geometries and localized flow structures. A source-term discretization is derived for nonuniform bottom that balances the discrete flux integral both for still water and in dry regions. This primitive-variable formulation is uniformly valid in wet and dry regions with embedded wetting and drying fronts. A fully nonlinear implicit scheme and both nonlinear and time-linearized explicit schemes are developed for the time integration. The implicit scheme is solved by a parallel Newton-iterative algorithm with numerically computed flux Jacobians. A concise treatment of characteristic-variable boundary conditions with source terms is also given. Computed results obtained for the one-dimensional dam break on wet and dry beds and for normal-mode oscillations in a circular parabolic basin are in very close agreement with the analytical solutions. Other results for a forced breaking wave with friction interacting with a sloped bottom demonstrate a complex wave motion with wetting, drying and multiple interacting wave fronts. Finally, a highly nonuniform, coastline-conforming unstructured grid is used to demonstrate an unsteady simulation that models an artificial coastal flooding due to a forced wave entering the Gulf of Mexico.     

Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm

Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm is proposed, and a fitness function is provided. Simulations are conducted using the adaptive niche immune genetic algorithm, the simulated annealing algorithm, the quantum genetic algorithm and the simple genetic algorithm, respectively. The results show that the adaptive niche immune genetic algorithm performs better than the other three algorithms in terms of the multi-user cognitive radio network resource allocation, and has quick convergence speed and strong global searching capability, which effectively reduces the system power consumption and bit error rate.     

五分类血液分析仪的智能光学系统设计

目前国内血液分析仪的白细胞五分类大多以硬件方式实现,且存在硬件结构复杂,制作成本高和过度依赖某些精密部件等问题。为简化五分类仪器的系统结构,提出了一种用于白细胞五分类的智能光学系统,该系统以全光学技术作为白细胞检测方式,采用VC6.0作为软件开发平台,建立了RBF神经网络的白细胞五分类识别算法模型,整个细胞识别和分类过程完全由软件实现,从而降低硬件复杂程度,减小了外界干扰因素的影响。实验结果：样机对LYM、MON、NEU、EOS、BAS的测试相对偏差分别为1.43%、4.41%、3.92%、2.94%、11.1%,满足了国家标准中的性能要求,故仪器整体的分类结果比较理想。结论：本文提出的智能光学系统具有性能稳定可靠、抗干扰能力强的特点。     

一种基于多准则决策和PSO-LM混合优化算法的多峰Brillouin散射谱的特征提取方法

采用传统方法对多峰Brillouin散射谱进行拟合的过程中,通常是以谱线最大功率点为基准的,却忽略了其他比该点小但却是极值的功率点。这样获得的拟合曲线通常只有一个峰值,相当于把除最高峰之外还有多个小峰的多峰Brillouin散射谱进行了简化,导致大量有用信息的丢失。为了提高Brillouin散射谱的特征提取精度,提出了一种基于MCDM和PSO-LM混合优化算法的多峰Brillouin散射谱特征提取方法(MCDM-PSO-LM)。MCDM可以识别和准确定位多峰Brillouin散射谱的各个波峰和波谷;PSO-LM混合优化算法可以实现分别对各个波峰和波谷的曲线进行拟合并找到每一个波峰的中心频率,该算法既克服了PSO算法过早收敛于局部极值和LM算法依赖初值的问题,又可以将PSO算法的全局搜索能力和LM算法的局部收敛能力结合在一起。较传统算法而言,MCDM-PSO-LM算法保证了对最优值求解的速度和精度,提高了运算能力,使解析解最大限度地接近最优值。分别在不同信噪比和不同线宽条件下进行仿真验证,频移和温度误差分析结果表明,MCDM-PSO-LM方法可以对多峰Brillouin散射谱的各个波峰与波谷进行准确定位,可用于多峰Brillouin散射谱的特征提取,识别效果明显强于传统算法,提高了信息分析的准确性。