Some Random Coincidence Point and Common Fixed Point Results in Cone Metric Spaces Over Banach Algebras

In this paper,we obtain some tripled common random fixed point and tripled random fixed point theorems with several generalized Lipschitz constants in such spaces.We consider the obtained assertions without the assumption of normality of cones.The presented results generalize some coupled common fixed point theorems in the existing literature.

A RANDOM FIXED POINT ITERATION FOR THREE RANDOM OPERATORS ON UNIFORMLY CONVEX BANACH SPACES

In the present paper we introduce a random iteration scheme for three random operators defined on a closed and convex subset of a uniformly convex Banach space and prove its convergence to a common fixed point of three random operators. The result is also an extension of a known theorem in the corresponding non-random case.

On a Class of Plane Random Walks with Absorbing Points

L. Shapiro has presented and solved a problem of a class of random walks with absorbing points on plane lattice points .[1]He divided the all lattice points on line y=x(x>0) into two classes by modulo 2, and selected one of the two classes to be the set of absorbing points. In this paper,we generalize the Shapiro problem:divide the all lattice points on line y = x(x>0) into k classes by modulo k,and select one class or more classes of the k classes to be the set of absorbing points. We solve the generalized problem by using the residue method and give an application of it to probability theory.

Effect of Quadrat Shape on Spatial Point Pattern Performance of Haloxylon ammodendron

In this study, we investigated the natural growth of Haloxylon ammodendron forest in Moso Bay, southwest of Gurbantunggut Desert. Random sample analysis was used to analyze the spatial point pattern performance of Haloxylon ammodendron population. ArcGIS software was used to summarize and analyze the spatial point pattern response of Haloxylon ammodendron population. The results showed that: 1) There were significant differences in the performance of point pattern analysis among different random quadrants. The paired t-test for variance mean ratio showed that the P values were 0.048, 0.004 and 0.301 respectively, indicating that the influence of quadrat shape on the performance of point pattern analysis was significant under the condition of the same optimal quadrat area. 2) The comparative analysis of square shapes shows that circular square is the best, square and regular hexagonal square are the second, and there is no significant difference between square and regular hexagonal square. 3) The number of samples plays a decisive role in spatial point pattern analysis. Insufficient sample size will lead to unstable results. With the increase of the number of samples to more than 120, the V value and P value curves will eventually stabilize. That is, stable spatial point pattern analysis results are closely related to the increase of the number of samples in random sample square analysis.

Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings

In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained.

Spatio-temporal point pattern analysis on Wenchuan strong earthquake

For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aflershocks with magnitude M≥4.0, M≥4.5, and M≥5.0. It is found that these data exhibit the spatio-temporal clustering on a certain distance scale and on a certain time scale. In particular, the space-time interaction obviously strengthens when the distance is less than 60 km and the time is less than 260 h for the first two aftershock sequences; however, it becomes strong when the distance scale is less than 80 km and the time scale is less than 150 h for the last aftershock sequence. The completely spatial randomness analysis on the data regardless of time component shows that the spatial clustering of the aftershocks gradually strengthens on the condition that the distance is less than 60 km. The results are valuable for exploring the occurrence rules of the Wenchuan strong earthquake and for predicting the aftershocks.

RANDOM APPROXIMATION OF AN ADDITIVE FUNCTIONAL EQUATION OF m-APPOLLONIUS TYPE

In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation：∑mi=1 f（z-xi）=mf（z-1/m2∑mi=1xi）-1/m∑1≤i〈j≤mf（xi＋xj）,where m is a natural number greater than 1,in random normed spaces. 更多还原

Modified fuzzy point estimate method and its application to slope reliability analysis

A slope engineering system is a complex system, in which many uncertaintiesexist, including random uncertainties and fuzzy uncertainties. Traditionally, random uncertaintieswere often considered, while fuzzy uncertainties were ignored. Therefore, fuzzy-random methodsshould he proposed. A fuzzy point estimate method was proposed by Dodagoudar, that is, consideringthe effect of fuzzy-random factors, the fuzzy-random limit state function of slopes is changed torandom interval limit state function by the lambda level cutting, then the moments of the functioncan be obtained by the Rosenblueth's method, and the stability state of slopes can be evaluated bysynthesizing a group of moments. But in Dodagoudar's method, Rosenblueth's state function iscomposed of only two kinds of combinations of parameters rather than 2~n kinds of combinations. So amodified fuzzy point estimate method is proposed by the authors, and it is used in a slopereliability analysis.

THE VALUE DISTRIBUTION OF RANDOM DIRICHLET SERIES ON THE RIGHT HALF PLANE(Ⅱ)

Kahane has studied the value distribution of the Gauss-Taylor serieswhere {Xn} is a complex Gauss sequence and In this paper, by trans-forming the right half plane into the unit disc and setting up some important inequal-ities, the value distribution of the Dirichlet series is studied where {Xn}is a sequence of some non-degenerate independent random variable satisfying conditions:EXn = 0; Xn or ReXn or ImAn of bounded density. Thereexists α> 0 such that Vn : (the classic Gauss and Steinhaus random variables are special cases of such random variables). The important results are obtained that every point on the line Res = 0 is a Picard point of the series without finite exceptional value a.s..

基于FPGA的Edwards曲线标量乘法改进与实现

点加是Edwards曲线标量乘法的基本运算,当点加算法确定后,通过减少点加运算次数来提高标量乘法运算效率是一种有效的方法。首先,根据标量乘法在椭圆曲线公钥密码中的使用特点,将标量乘法分成固定点标量乘法、随机点标量乘法和多点标量乘法;其次,采用预计算和窗口法来减少标量乘法中的点加运算次数;最后,在复旦微的JFM7K325T的现场可编程门阵列(FieldProgrammableGateArray,FPGA)中进行了实现和测试。结果表明,与原有实现方法相比,改进算法计算256比特固定点标量乘法速度提升了450%,计算随机点标量乘法速度提升了39%,计算多点标量乘法速度提升了66%。

The Power of Change-Point Test for Two-Phase Regression

In this paper, the roughness of the model function to the basis functions and its properties have been considered. We also consider some conditions to take the limit of the roughness when the observations are i.i.d. An explicit formula to calculate the power of change-point test for the two phases regression through the roughness was obtained.

RANDOM SYSTEMS OF HARD PARTICLES:MODELS AND STATISTICS

This paper surveys models and statistical properties of random systems of hard particles. Such systems appear frequently in materials science, biology and elsewhere. In mathematical-statistical investigations, simulations of such structures play an important role. In these simulations various methods and models are applied, namely the RSA model, sedimentation and collective rearrangement algorithms, molecular dynamics, and Monte Carlo methods such as the Metropolis-Hastings algorithm. The statistical description of real and simulated particle systems uses ideas of the mathematical theories of random sets and point processes. This leads to characteristics such as volume fraction or porosity, covariance, contact distribution functions, specific connectivity number from the random set approach and intensity, pair correlation function and mark correlation functions from the point process approach. Some of them can be determined stereologically using planar sections, while others can only be obtained using three-dimensional data and 3D image analysis. They are valuable tools for fitting models to empirical data and, consequently, for understanding various materials, biological structures, porous media and other practically important spatial structures.

Phase diagrams of spin-3/2 Ising model in the presence of random crystal field within the effective field theory based on two approximations

The bimodal random crystal field （A） effects are investigated on the phase diagrams of spin-3/2 Ising model by using the effective-field theory with correlations based on two approximations： the general van der Waerden identity and the approximated van der Waerden identity. In our approach, the crystal field is either turned on or turned off randomly for a given probability p or q = 1 -p, respectively. Then the phase diagrams are constructed on the （A,kT/J） and （p,kT/J） planes for given p and A, respectively, when the coordination number is z = 3. Furthermore, the effect of randomization of the crystal field is illustrated on the （△,kT/J） plane for p = 0.5 when z - 3,4, and 6. All these are carried out for both approximations and then the results are compared to point out the differences. In addition to the lines of second-order phase transitions, the model also exhibits first-order phase transitions and the lines of which terminate at the isolated critical points for high p values.

随机误差传递的高空气象秒级数据快速校验方法

【目的】为保证气象预报结果的准确性。【方法】提出了考虑随机误差传递的高空气象秒级数据快速校验方法。对高空气象秒级数据进行预处理,包括数据中心化处理、特征点提取。数据中心化的处理方式为实施各组数据的加权平均处理,获得新的数据组作为基准数据;特征点提取使用的处理方法为遍历法,需要遍历全部数据点。考虑数据获取过程中的随机误差传递情况,对预处理后的高空气象秒级数据实施空间一致性检查、内部一致性检查。应用集合经验模态分解EEMD(Ensemble Empirical Mode Decomposition)算法与对比源反演CSI(Contrast Source Inversion)算法构建基于CSI-EEMD的高空气象秒级数据快速校验模型,实施数据得到快速校验。【结果】测试结果表明,该方法能够实现4个气象站数据的快速校验,校验结果的均方根误差与平均绝对误差均低于0.1,实现了数据的质量控制。【结论】将该方法应用于气象站数据校验中,可以实现精准度的数据校验,具有一定的实用价值。

基于多特征约束的露天采场道路点云提取

针对露天采场道路点云数据通过法向量、路缘石等点云特征难以准确提取的问题,提出了一种多特征约束的露天采场道路点云提取方法.以辽阳市千山石灰石矿露天采场激光点云为数据源,首先对原始数据进行降采样;然后基于单点RGB信息、邻域RGB信息、邻域高差、邻域粗糙度、反射强度5类点云特征,制作并划分了训练集和验证集,利用随机森林算法构建了道路点云提取模型并进行了优化,进一步引入欧式聚类算法改进了道路点云提取模型结果,最后评估了露天采场道路点云提取结果.结果表明,本文方法可以实时有效准确地提取露天采场道路点云数据.

改进双向快速搜索随机树的无人艇路径规划

针对双向快速搜索随机树(bidirectional rapidly-exploring random tree, BI-RRT)算法在全局路径规划时存在搜索效率低、路径拐点较多等问题,提出一种改进BI-RRT的水面无人艇(unmanned surface vehicle, USV)全局路径规划算法。该算法采取了极度贪心的思想、高斯偏置随机点采样方法以及启发式的节点扩展策略,同时对节点扩展和搜索树连接进行角度约束,将生成的路径进行剪枝和3次B样条优化处理。结果表明,相对于改进前,改进的BI-RRT在平均时间、随机采样点和平均路径上分别减少了40.5%、65.0%和24.0%。改进后的算法时间、采样点和搜索树扩展大幅度减少,路径平滑度提高且路径更短。

基于激光诱导击穿光谱(LIBS)的煤灰熔点快速检测

由于劣质煤的存在,燃煤时锅炉内极易出现结渣问题,不仅降低了煤的利用率、电厂的经济效益,且使火电厂存在安全隐患,如管壁超温爆管等,不符合国家节能减排的发展战略要求。因此炉内结渣是影响火电机组和气化工艺可靠运行的关键因素之一,准确预测灰熔点可以提前调整炉膛出口温度以避免结渣。采用激光诱导击穿光谱仪(LIBS)对33个火电厂常用煤燃烧后得到的煤灰样品采集其中所有元素的光谱,分别建立煤灰中的所有元素的谱线强度与煤灰熔点的随机森林模型、支持向量机回归模型和线性回归模型,直接预测煤灰熔点温度。采用基于马氏距离(MD)的异常数据剔除算法和基于稀疏矩阵的基线估计与降噪算法(BEADS),对粉煤灰样的全光谱数据进行了预处理。将全部数据划分为70%训练集和30%测试集,并以平均相对误差(MRE)作为判断模型拟合程度的标准,其中随机森林模型对粉煤灰熔点的预测平均相对误差(MRE)为54.74%,支持向量机回归模型的预测平均相对误差为60.08%,而线性回归模型的预测平均相对误差达到了9.78%。研究结果表明,线性回归模型对煤灰熔点的预测结果更准确。将便携式LIBS光谱仪与机器学习算法相结合,用于煤灰熔点的快速检测,可有效避免锅炉结渣问题,实现火电厂安全性和经济效益的同步提高,有广阔的发展前景。

无人机激光雷达杉木人工林碳储量估测

森林碳储量是衡量森林生态系统基本特征的重要指标,传统碳储量估测方式需要耗费大量的时间、人力、物力等,因此利用无人机搭载激光雷达获取机载激光数据并建立森林碳储量估测模型,为获取区域内森林碳储量提供参考,从而更好地对森林资源进行监测。以杉木人工林为研究对象,利用机载激光雷达点云数据获取点云特征变量,以此作为建模变量进行模型研建。通过不同筛选变量方式选择建模变量,分别建立非线性回归模型、线性回归模型和随机森林模型并进行模型评价,通过对比模型的决定系数(R^(2))、均方根误差(RMSE)和平均绝对误差(MAE)选出最优模型,用于后续研究。结果表明,1)3种模型拟合效果最佳的为随机森林模型,其R^(2)为0.94,RMSE为0.53 t/hm^(2),MAE为0.44 t/hm^(2)。非线性回归模型R^(2)为0.71,RMSE为0.66 t/hm^(2),MAE为0.56 t/hm^(2);线性回归模型R^(2)为0.67,RMSE为0.88 t/hm^(2),MAE为0.80 t/hm^(2)。2)共计提取101个点云特征变量,通过变量筛选发现高度变量、密度变量无论是相关性还是重要性,均大于强度变量。3)对比是否加入优选变量对随机森林模型预测精度的影响,加入优选变量后模型R^(2)没有变化,但RMSE与MAE小于未加入优选变量,精度有所提高。利用机载激光雷达点云数据获取的点云特征变量建立模型,对比非线性回归和线性回归模型,随机森林模型精度最高,用其估算得到研究区内碳储量为480.65 t/hm^(2),与实测值最相近。因此随机森林模型更适合于区域森林碳储量的估测。

基于三维点云的磁极焊缝识别及机器人轨迹生成技术

针对大型水电站发电机磁极变长度、变间隙的复杂焊缝存在的示教编程效率低、精度差的问题,开发了一种基于光栅视觉传感的焊缝识别及机器人轨迹免示教生成技术.采用安装于机器人末端的光栅传感器获取不同部位的磁极焊缝点云,提出了一种结合机器人工具位姿变换矩阵和迭代最近点算法(ICP)的点云配准算法,得到大尺寸磁极焊缝完整点云数据.基于随机采样一致性(RANSAC)开发了焊缝识别算法,实现了机器人焊接轨迹的自动生成.结果表明,该算法可识别出多种复杂工况的磁极焊缝,识别率高,抗干扰能力强,平均识别误差在±0.4 mm范围内,满足焊接要求.

基于特征点匹配的排水管道声点云模型配准算法

三维重建技术逐渐成为获取全面、完备、准确的排水管道信息的关键手段;而实际检测受到管道堵塞等工况与管道检测规程等因素限制,造成所获得的管道声呐点云模型会出现位姿不同、部分重叠或空缺等情况,需要通过配准获取完整管道模型;同时,传统ICP算法针对管道模型存在效率低、精度差的问题;因此,文章提出基于特征点匹配的粗配准与改进的ICP精细配准相结合的点云配准算法;首先,利用ISS特征点检测法检测出模型特征点,通过FPFH对特征点进行进一步的描述;其次,采用RANSAC算法筛选出正确特征匹配点集,利用四元数法解算出初始变换参数完成粗配准;最后,在粗配准基础上,通过改进最近对应点查询的ICP算法完成精细配准;实验结果表明了该文算法的可行性与优越性,能为后续排水管道缺陷检测提供高完备、全面、准确的点云模型。