Performance analysis of multi-channel order statistics detector for range-spread target

The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optimal detector,which requires many processing channels.The structure of such optimal detector is complex.Therefore,a simpler quasi-optimal detector is then introduced.The quasi-optimal detector,called the strong scattering cells’ number dependent order statistics（SND-OS） detector,takes the form of an average of maximum strong scattering cells with a known number.If the number of strong scattering cells is unknown in real situation,the multi-channel order statistics（MC-OS） detector is used.In each channel,a various number of maximums scattered from target are averaged.Then,the false alarm probability analysis and thresholds sets for each channel are given,following the detection results presented by means of Monte Carlo simulation strategy based on simulated target model and three measured targets.In particular,the theoretical analysis and simulation results highlight that the MC-OS detector can efficiently detect range-spread targets in white Gaussian noise.

Influence of statistical time range on estimating seismicity parameters

The influence of non-uniqueness in selecting statistical time ranges on seismicity parameters of b value and annual mean occurrence rate ν4 is widely analyzed and studied. The studied result states that the influence of statistical time range on the b value is generally smaller than on the annual mean rate. Owing to the exponentially functional relation between the annual mean rate and b value, the variation of b value by varying statistical time range brings about decrease or increase in the annual mean rates of each magnitude interval with power progression law. These results will exert a synthetic effect on seismic safety evaluation results in various regions in our country.

Reconstructing ancestral ranges in historical biogeography:properties and prospects

Recent years have witnessed a proliferation of quantitative methods for biogeographic inference. In particular, novel parametric approaches represent exciting new opportunities for the study of range evolution. Here, we review a selection of current methods for biogeographic analysis and discuss their respective properties. These methods include generalized parsimony approaches, weighted ancestral area analysis, dispersal-vicariance analysis, the dispersal--extinction--cladogenesis model and other maximum likelihood approaches, and Bayesian stochastic mapping of ancestral ranges, including a novel approach to inferring range evolution in the context of island biogeography. Some of these methods were developed specifically for problems of ancestral range reconstruction, whereas others were designed for more general problems of character state reconstruction and subsequently applied to the study of ancestral ranges. Methods for reconstructing ancestral history on a phylogenetic tree differ not only in the types of ancestral range states that are allowed, but also in the various historical events that may change the ancestral ranges. We explore how the form of allowed ancestral ranges and allowed transitions can both affect the outcome of ancestral range estimation. Finally, we mention some promising avenues for future work in the development of model-based approaches to biogeographic analysis.

An Integrated Use of Advanced T2 Statistics and Neural Network and Genetic Algorithm in Monitoring Process Disturbance

Integrated use of statistical process control (SPC) and engineering process control (EPC) has better performance than that by solely using SPC or EPC. But integrated scheme has resulted in the problem of “Window of Opportunity” and autocorrelation. In this paper, advanced T2 statistics model and neural networks scheme are combined to solve the above problems: use T2 statistics technique to solve the problem of autocorrelation;adopt neural networks technique to solve the problem of “Window of Opportunity” and identification of disturbance causes. At the same time, regarding the shortcoming of neural network technique that its algorithm has a low speed of convergence and it is usually plunged into local optimum easily. Genetic algorithm was proposed to train samples in this paper. Results of the simulation ex-periments show that this method can detect the process disturbance quickly and accurately as well as identify the dis-turbance type.

Stability of T. Chan’s Preconditioner from Numerical Range

A matrix is said to be stable if the real parts of all the eigenvalues are negative. In this paper, for any matrix An, we discuss the stability properties of T. Chan’s preconditioner cU (An) from the viewpoint of the numerical range. An application in numerical ODEs is also given.

STATISTICA计算机软件在化学实验数据分析中的应用

通过多种实例着重介绍STATISTICA软件在实验误差分析、一致性检验等实验数据可靠性分析方面的使用。使用证明 ,利用该软件可以大大提高数据分析的可靠性和科学性 。

Statistic Analysis on Quantitative Characteristics for Developing the DUS Test Guideline of Ranunculus asiaticus L.

Selection of quantitative characteristics, division of their expression ranges, and selection of example varieties are key issues on developing DUS Test Guidelines, which are more crucial for quantitative characteristics since their expressions vary in different degrees. Taking the development of DUS Test Guideline of Ranunculus asiaticus L. as an example, this paper applied statistic-based approaches for the analyses of quantitative characteristics. We selected 9 quantitative characteristics from 18 pre-selected characteristics, based on within-variety uniformity, stability between different growing cycles, and correlation among characteristics, by the analyses of coefficient of variation, paired-samples t-test and partial correlation. The expression ranges of the 9 selected quantitative characteristics were divided into different states using descriptive statistics and distribution frequency of varieties. Eight of the 9 selected quantitative characteristics were categorized as standard characteristics as they showed one peak in distribution frequency of 120 varieties in various expressions of the characteristics, whereas, plant height can be categorized as grouping characteristic since it gave two peaks, and can group the varieties into pot and cut varieties. Finally, box-plot was applied to visually select the example varieties, and varieties 7, 12, and 28 were determined as the example varieties for plant height. The methods described in this paper are effective for the selection of quantitative characteristics, division of expression ranges, and selection of example varieties in Ranunculus asiaticus L. for DUS test, and may also be interest for other plant genera.

A Novel Statistical Manifold Algorithm for Position Estimation

In this paper, a novel statistical manifold algorithm is proposed for position estimation of sensor nodes in a wireless network, making full use of distance information available among unknown nodes and simultaneous localization of multiple unknown nodes. To begin, a ranging model including the distance information among unknown nodes is established. With the reparameterization of the natural parameter and natural statistic,the solution problem of the ranging model is transformed into a parameter estimation problem of the curved exponential family.Then, a natural gradient method is adopted to deal with the parameter estimation problem of the curved exponential family.To ensure the convergence of the proposed algorithm, a particle swarm optimization method is utilized to obtain initial values of the unknown nodes. Experimental results indicate that the proposed algorithm can improve the positioning accuracy, compared with the traditional algorithm.

The Statistical Significance Test of Regional Climate Change Caused by Land Use and Land Cover Variation in West China

The West Development Policy being implemented in China is causing significant land use and land cover （LULC） changes in West China. With the up-to-date satellite database of the Global Land Cover Characteristics Database （GLCCD） that characterizes the lower boundary conditions, the regional climate model RIEMS-TEA is used to simulate possible impacts of the significant LULC variation. The model was run for five continuous three-month periods from 1 June to 1 September of 1993, 1994, 1995, 1996, and 1997, and the results of the five groups are examined by means of a student t-test to identify the statistical significance of regional climate variation. The main results are： （1） The regional climate is affected by the LULC variation because the equilibrium of water and heat transfer in the air-vegetation interface is changed. （2） The integrated impact of the LULC variation on regional climate is not only limited to West China where the LULC varies, but also to some areas in the model domain where the LULC does not vary at all. （3） The East Asian monsoon system and its vertical structure are adjusted by the large scale LULC variation in western China, where the consequences are the enhancement of the westward water vapor transfer from the east oast and the relevant increase of wet-hydrostatic energy in the middle-upper atmospheric layers. （4） The ecological engineering in West China affects significantly the regional climate in Northwest China, North China and the middle-lower reaches of the Yangtze River; there are obvious effects in South, Northeast, and Southwest China, but minor effects in Tibet.

Statistic PID Tracking Control for Non-Gaussian Stochastic Systems Based on T-S Fuzzy Model

A new robust proportional-integral-derivative （PID） tracking control framework is considered for stochastic systems with non-Gaussian variable based on B-spline neural network approximation and T-S fuzzy model identification. The tracked object is the statistical information of a given target probability density function （PDF）, rather than a deterministic signal. Following B-spline approximation to the integrated performance function, the concerned problem is transferred into the tracking of given weights. Different from the previous related works, the time delay T-S fuzzy models with the exogenous disturbances are applied to identify the nonlinear weighting dynamics. Meanwhile, the generalized PID controller structure and the improved convex linear matrix inequalities （LMI） algorithms are proposed to fulfil the tracking problem. Furthermore, in order to enhance the robust performance, the peak-to-peak measure index is applied to optimize the tracking performance. Simulations are given to demonstrate the efficiency of the proposed approach.

SOUND SOURCE LOCALIZATION OF DIGITAL HEARING AIDS USING WAVELET BASED MULTIVARIATE STATISTICAL METHOD

The letter proposed a sound source localization method of digital hearing aids using wavelet based multivariate statistics with the Generalized Cross Correlation (GCC) algorithm. Haar wavelet is used to decompose GCC sequences and extract four wavelet characteristics. And then, Hotelling T2 statistical method is used to fuse the four wavelet characteristics. The statistical value is used to judge the number of sound sources and obtain corresponding time delay estimation which is used to localize the position of sound source. The experimental results show that the proposed method has better robustness in an environment with severe noise and reverberation. Meanwhile, the complexity of al-gorithm is moderate, which is available for sound source localization of hearing aids.

华法林抗凝治疗稳定性评价新探索:基于改良SAMe-T-PDW2-LAD2积分

背景 目前关于华法林抗凝治疗稳定性的研究较少,现有主要评估方法为SAMe-TT2R2积分,但该积分具有较为明显的局限性且不适用于非白种人群,前期研究显示血小板分布宽度(PDW)以及左心房内径(LAD)与治疗目标范围内的时间百分比(TTR)的达标具有密切关系,可否将二者纳入现有的积分体系并加以改良运用值得临床深思。目的 探索改良SAMe-T-PDW2-LAD2积分对华法林抗凝治疗稳定性常用国际标准化比值(INR)在TTR达标的预测价值,以期为改进现有华法林抗凝治疗稳定性的评价方案提供方法学参考。方法 选取2021年1月—2023年6月就诊于九江市第一人民医院的164例使用华法林抗凝治疗的持续性非瓣膜性心房颤动患者作为研究对象。根据TTR评价界值(65%)将TTR≥65%定义为达标,即华法林抗凝治疗稳定性为高质量抗凝;将TTR<65%定义为未达标,即华法林抗凝治疗稳定性为非高质量抗凝。同时根据上述标准将患者分为两组:TTR达标组(TTR≥65%,46例)和TTR未达标组(TTR<65%,118例)。改良SAMe-T-PDW2-LAD2积分保留了既往SAMe-TT2R2积分中性别、年龄、合并疾病、合并用药这4项参数,并尝试将种族、吸烟这2项参数删除,代替以“PDW升高”和“LAD增大”并分别积分为2分;收集并比较两组患者的上述参数。采用二元Logistic回归分析探讨华法林抗凝治疗稳定性TTR达标的影响因素;分别绘制SAMe-TT2R2积分、改良SAMe-T-PDW2-LAD2积分评价华法林抗凝治疗稳定性TTR达标的受试者工作特征(ROC)曲线。结果 单因素分析结果显示,两组患者年龄及合并心力衰竭、合并高脂血症、吸烟、PDW升高、LAD增大比例比较,差异有统计学意义(P<0.05)。二元Logistic回归分析结果显示,年龄(OR=0.882,95%CI=0.812~0.958,P=0.003)、PDW升高(OR=0.443,95%CI=0.282~0.697,P<0.001)、LAD增大(OR=0.031,95%CI=0.001~0.853,P=0.040)是华法林抗凝治疗稳定性TTR达标的影响因素。SAMe-TT2R2积分不同分值组TTR、TTR达标率比较,差异有统计学意义(P<0.05);其中积分6、7分组TTR高于积分2、3、4、5分组(P<0.05);积分7分组TTR达标率高于积分2、3、4、5、6分组(P<0.05)。改良SAMe-T-PDW2-LAD2积分不同分值组TTR、TTR达标率比较,差异有统计学意义(P<0.05);其中积分3、4、5、6、7分组TTR低于积分0、1、2分组(P<0.05);积分2分组TTR达标率高于积分0、1、3、4、5、6、7分组(P<0.05)。ROC曲线结果显示,SAMe-TT2R2积分评价华法林抗凝治疗稳定性TTR达标的ROC曲线下面积(AUC)为0.803(95%CI=0.737~0.868),最佳截断值为5.5分,灵敏度为1,特异度为0.508;改良SAMe-T-PDW2-LAD2积分评价华法林抗凝治疗稳定性TTR达标的AUC为0.814(95%CI=0.751~0.877),最佳截断值为2.5分,灵敏度为0.848,特异度为0.737。结论 年龄、PDW升高、LAD增大是华法林抗凝治疗稳定性TTR达标的影响因素。SAMe-TT2R2积分评价华法林抗凝治疗稳定性存在较多的局限性,改良SAMe-T-PDW2-LAD2积分评价华法林抗凝治疗稳定性具有较好的临床应用价值。

外周血T细胞亚群PD-1和CD28参考范围和影响因素

目的建立健康成人外周血T细胞亚群PD-1和CD28表达参考区间,并探究其与常规实验室指标的相关性。方法收集2022年11月至2023年1月在本院体检的120例健康体检者外周血,用流式细胞术检测淋巴细胞中CD3^(+)、CD4^(+)和CD8^(+)T细胞及其表面PD-1和CD28的表达,CD8^(+)T根据CD28和PD-1表达不同细分6个亚群,对这些指标的比例和绝对值建立参考范围。T细胞各亚群与常规指标进行相关性分析。结果健康成人外周血PD-1(%)表达率:CD4>CD3;CD28(%):CD4>CD3>CD8;PD1和CD28阳性计数:CD3>CD4>CD8。女性CD4^(+)(%)显著低于男性;年龄与CD8和CD3计数以及CD28计数负相关,与CD8^(+)CD28^(+)上PD-1表达呈正相关;红细胞以及血小板计数与CD8相关亚群上PD-1hi和PD-1int的表达和计数呈正相关,但和CD4^(+)(%)呈负相关。CD8^(+)CD28-亚群PD-1的表达和计数与ALB呈正相关;CD8^(+)CD28^(+)亚群PD-1计数和LDL呈正相关。结论本文建立了健康成人外周血T细胞亚群PD-1和CD28表达参考区间,并发现性别、年龄、红细胞、血小板、血脂和营养状态等对T细胞亚群以及PD-1和CD28表达均可造成影响。

A Statistical Comparison of Traffic Measurements from the Moving versus Stationary Observer Methods

Data of traffic flow, speed and density are required for planning, designing, and modelling of traffic stream for all parts of the road system. Specialized equipments such as stationary counts are used to record volume and speed;but they are expensive, difficult to set up, and require periodic maintenance. The moving observer method was proposed in 1954 by Wardrop and Charlesworth to estimate these variables inexpensively. Basically, the observer counts the number of vehicles overtaken, the number of vehicles passed, and the number of vehicles encountered while traveling in the opposite direction. The trip time is reported for both travel directions. Additionally, the length of road segment is measured. These variables are then used in estimating speeds and volumes. In a westbound direction from Interstate Highway 30 (I-30) in the DFW area, this study examined the accuracy and feasibility of this method by comparing it with stationary observer method as the standard method for such counts. The statistical tests were used to test the accuracy. Results show that this method provides accurate volume and speed estimates when compared to the stationary method for the road segment with three lanes per direction, especially when several runs are taken.

非中心t分布合格判定方法中k值计算

非中心t分布是批量产品电磁兼容符合性评定的重要统计技术之一,k值是非中心t分布合格判定方法中的关键参数,在GB/Z 6113.403-2020中仅给出了80%/80%准则的有限样本下的k值,且未给出具体计算方法。本文结合电磁兼容试验统计技术实际应用情况,从非中心t分布分位数表中有对应分位数概率(P)值而无置信度(α)值、无P值且无α值两方面进行计算方法研究,提出了适用于不同准则和不同样本的k值计算方法,对不同计算方法进行了对比研究分析,指出基于线性插值和指数逼近拟合算法的准确性、与标准的一致性较高,最后给出了两种典型的k参数计算值。旨在为电磁兼容非中心t分布试验符合性统计评定提供工程指导和参考。

綦江地区健康成人外周血T淋巴细胞亚群参考范围分析

目的探讨綦江地区健康成人外周血T淋巴细胞亚群的变化特点,进行统计分析,建立綦江地区T淋巴细胞亚群的实验室参考范围。方法选取2022年4月1日—2023年4月10日于綦江地区进行健康体检的311例体检者为研究对象,平均年龄为(32.35±5.83)岁。采集健康体检者清晨空腹静脉血,采用流式细胞术检测311例健康成人外周血T淋巴细胞亚群。结果男性总淋巴细胞绝对计数、总T淋巴细胞绝对计数、CD8^(+)淋巴细胞百分比、CD8^(+)淋巴细胞绝对计数高于女性,CD4^(+)淋巴细胞百分比低于女性,差异有统计学意义(P<0.05);两组总T淋巴细胞百分比、CD4^(+)淋巴细胞绝对计数、CD4^(+)/CD8^(+)比较,差异无统计学意义(P>0.05)。不同年龄组各项指标比较,差异无统计学意义(P>0.05)。采用百分位数法对311例健康体检者外周血T淋巴细胞亚群进行分析,并将各项指标的95%可信区间作为綦江地区健康成人外周血T淋巴细胞亚群的参考范围,具体如下:总淋巴细胞绝对计数1520×10^(6)/L~3780×10^(6)/L、总T淋巴细胞绝对计数950×10^(6)/L~2840×10^(6)/L、总T淋巴细胞百分比49%~85%、CD4^(+)淋巴细胞绝对计数545×10^(6)/L~1420×10^(6)/L、CD4^(+)淋巴细胞百分比26%~50%、CD8^(+)淋巴细胞绝对计数318×10^(6)/L~1255×10^(6)/L、CD8^(+)淋巴细胞百分比12%~42%、CD4^(+)/CD8^(+)为0.70~2.90。结论性别会影响健康成人外周血T淋巴细胞亚群的部分指标,建立适合本地区健康成人外周血T淋巴细胞亚群参考范围对疾病的诊断具有极其重要的意义。

基于P&T-GC/MS指纹图谱技术的烟用香精质量控制评价方法

利用P&T-GC/MS指纹图谱技术,结合夹角余弦相似度、峰匹配及多元T^(2)控制图,对烟用香精的质量稳定性进行综合评价,结果表明:P&T最优的前处理条件为吹扫时间14 min,吹扫温度40℃,解析温度200℃,在该条件下测得烟用香精中各挥发性成分特征色谱峰的RSD为1.36%~6.98%,说明该方法精密度良好;指纹图谱结合夹角余弦相似度、峰匹配分析及多元T^(2)控制图,可快速识别组分发生变化的烟用香精样品,及时发现样品的错混、质量浓度改变等问题,有效监控烟用香精的质量稳定性,并有助于进一步分析化学组分发生变化的根本原因。

基于t检验的光伏电站中能效异常光伏组件识别研究

由于目前光伏电站能效指标缺乏具体的应用方式,光伏组件发电效率优劣的界限模糊,且光伏电站在正常运行中光伏组件I-V特性曲线难以获取,导致目前识别异常光伏组件的方法难以应用到实际光伏电站中。基于此,利用光伏组件能效比服从正态分布的特点,提出了一种基于t检验的光伏电站中能效异常光伏组件的识别方法,对光伏组件实际能效比与理论能效比之差进行假设检验,并结合实际光伏电站进行实验验证。研究结果表明:该方法可以有效识别异常光伏组件,可为光伏电站的运维提供数据支持。

The Law of Iterated Logarithm of Rescaled Range Statistics for AR(1) Model

Let {Xn,n ≥ 0} be an AR（1） process. Let Q（n） be the rescaled range statistic, or the R/S statistic for {Xn} which is given by （max1≤k≤n（∑j=1^k（Xj - ^-Xn）） - min 1≤k≤n（∑j=1^k（ Xj - ^Xn ））） /（n ^-1∑j=1^n（Xj -^-Xn）^2）^1/2 where ^-Xn = n^-1 ∑j=1^nXj. In this paper we show a law of iterated logarithm for rescaled range statistics Q（n） for AR（1） model.

浙江地区健康青少年和成人外周血T淋巴细胞免疫表型调查及正常参考值范围的建立

目的通过对健康青少年和成人外周血T淋巴细胞免疫表型分布调查，建立健康人外周血T淋巴细胞免疫表型正常参考值范围。方法选择浙江地区义务献血和健康体检者385例，血样用Multi TEST四色特异性T淋巴细胞亚群荧光抗体进行荧光标记，FACS Callibur流式细胞仪检测样品，Mulfiset程序获取数据并分析结果，SPSS 12．0软件包进行统计分析。以百分位数法，采用95％可信区间确定正常参考值范围。结果男性和女性的CD3^＋的百分率和CD3^＋CD4^＋百分率和绝对数均有差异，表现为女性高于男性。而CD3^＋绝对数和CD3^＋CD8^＋百分率和绝对数没有性别差异。T淋巴细胞免疫表型各个指标在不同年龄组之间均有差异，表现CD3^＋CD8^＋（相对数和绝对值）随年龄组增大而逐渐下降趋势，而CD3^＋CD4^＋（相对数和绝对值）则随年龄组增大而逐渐增加。浙江省健康人T淋巴细胞免疫表型参考值范围：CD3^＋百分数（％）：47．98～82．60；CD3^＋绝对数（个／μl）：712．49～2367．55；CD8^＋百分率（％）：14．24～41．48；CD8^＋绝对数（个／μl）：219．14～1109．81；CD4^＋百分率（％）：24．15～51．66；CD4^＋绝对数（个／μl）：383．61～1345．60；CD4／CD8：0．70～3．25。结论健康人淋巴细胞免疫表型的分布存在性别和年龄差别。由于这种差别细微，可以在同一种族同一区域建立统一的正常参考值范围。