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1.
This paper studies the problem of detecting multiplechanges at unknown times in the mean level of elision in thetrimeter sequences of the Orestes, a play written by theAncient Greek dramatist Euripides (485–406 B.C.). Change-detection statistics proposed by MacNeill (1978) and Jandhayala and MacNeill(1991) are adopted for this purpose. Analysis of the trimetersequences yields several points of change. A general explanation fortheir occurrence appears to be that Euripides varies his use ofelision according to the emotional content of his text, i.e., heseems to change the form to support the content and, thus, seems touse elision frequency as a dramatic instrument.  相似文献   

2.
重点对多输入多输出(MIMO)无线通信系统的信道模型、空时分组码(Alamouti)以及垂直分层空时码(V-BLAST)空间复用技术进行了仿真分析.首先利用MATLAB在信道建模中实现了基于瑞利环境下的信道容量仿真图,同时仿真并分析了天线相关性对信道容量的影响;然后进行了Alamouti方案和最大比接收合并(MRRC)之间的仿真分析;最后对V-BLAST系统中的线性检测(ZF)算法和最小均方误差(MMSE)算法做了仿真比较,从而得出V-BLAST系统优于非V-BLAST体系下的误码性能.  相似文献   

3.
深入分析了拷贝构造函数和转换构造函数的作用和实现方法,并指出了程序设计中出现的问题和解决方法。  相似文献   

4.
为解决局部放电信号检测中白噪声的抑制问题,在D. L. Donoho 和I. M. Johnstone 提出的多分辨分析小波阈值去噪方法的基础上,构造了一个双变量阈值函数.该阈值函数通过改变k值来调节阈值化小波系数与原始小波系数之间的恒定偏差;并通过改变参数m来调节平滑过渡区内曲线的阶次,用于局部微调,弥补了硬阈值法不连续性和软阈值法具有偏差的不足.仿真结果表明,改进后的小波阈值函数的信号去噪效果明显,具有较高的实用价值.  相似文献   

5.
Action research has been extensively used world-wide for decision making related to policy due to its nature of involving the researcher and decision maker in the process. Following independence in India, one of the major revolutions was brought about in the dairy sector with regard to complete management systems. Most innovations and changes occurred in the line function while the staff function was more often neglected in the overall change. The authors undertook an action research study focusing on staff function and relayed improvements that can influence policy related to decision making. The authors have also developed the MPS model for staff function which can help a company or industry in appraising their own staff and functions which can thereby aid in utilising their potential.  相似文献   

6.
由于无线传感器网络具有超大规模、与环境耦合紧密等特点,物理实验不可避免受到限制,仿真建模因此成为重要的研究手段.多分辨率建模作为复杂系统分布式仿真的关键技术,能够很好地满足无线传感器网络的仿真需要.本文简述了多分辨率建模相关的理论与技术,对其在无线传感器网络仿真研究中的应用意义做了分析,并且基于多分辨率建模方法提出了一种新的传感器网络仿真框架,最后通过仿真试验论证了新框架的可行性.  相似文献   

7.
多元线性回归分析在机组发电耗水率中的应用   总被引:1,自引:0,他引:1  
多元线性回归分析是一个有广泛适用性的多元统计分析方法。本文利用葛洲坝发电站的部分数据,对葛洲坝发电站一段时间内的库水位、出库流量及其对应的机组耗水率利用多元线性回归进行建模分析。显然,对这个问题的深入研究,可以有效地认识各种因素对机组发电耗水率的影响程度,从而可以更好地对机组发电耗水率进行预测。  相似文献   

8.
直扩系统中伪随机码序列调制的DPSK调制器   总被引:1,自引:0,他引:1  
论文概括介绍了直扩系统中伪随机编码调制的差分移相键控调制器的原理、方框图及用高密度的集成电路实现的方法。这种用PN码序列调制的DPSK扩频调制器能较好地抑制载波。  相似文献   

9.
In this paper, the problems of stability and stabilization are considered for a class of switched linear systems with slow switching and fast switching. A multiple convex Lyapunov function and a multiple discontinuous convex Lyapunov function are first introduced, under which the extended stability and stabilization results are derived with a mode‐dependent average dwell time switching strategy, where slow switching and fast switching are exerted on stable and unstable subsystems, respectively. These two types of Lyapunov functions are established in a constructive manner by virtue of a set of time‐varying functions. By using our proposed approaches, larger stability regions of system parameters are identified, and tighter bounds can be obtained for the mode‐dependent average dwell time. New mode‐dependent and time‐varying controllers are constructed for a class of switched control systems with stabilizable and unstabilizable subsystems as well. All the stability and stabilization conditions can be given in terms of strict linear matrix inequalities (LMIs), which can be checked easily by using recently developed algorithms in solving LMIs. Finally, two numerical examples are provided to show the effectiveness of the obtained results compared with the existing results.  相似文献   

10.
中国人口分布及空间相关分析   总被引:24,自引:0,他引:24  
刘德钦  刘宇  薛新玉 《遥感信息》2002,(2):2-6,T001
利用2000年人口普查信息,介绍了在人口地理信息系统中,通过三维模型显示,罗伦斯曲线,人口重心和人口潜力等方法,分析中国人口分布的特征。在此基础上,用空间相关方法对人口分布的现象进行分析,揭示了其空间地理分布的内在联系。  相似文献   

11.
Based on ICESat data and temperature and precipitation from 2003 to 2010 and used ANUSPLINE interpolation method and Theil\|Sen’s method,we analyzed and discussed lake water level change characteristic from 2003 to 2010,as well as the temporal\|spatial response of lake water level to climate changes.the results showed that most of lakes mainly distribute in the central and western region of TP,and their lake water levels are mainly between 4 500 to 5 000 meters.Lake water level of Tak kyel and Yamzhog Yumco in the southern of TP as well as Panggong in the western of TP showed a decreasing trend.Analysis of the relationship between lake water level and climate factor indicated that lake water level in different basin showed different trends because of varied temperature and precipitation.the increasing trend of lake volume was not only dependent on direct supply of precipitation,but also effected by melted water from glaciers and snow due to climate warming.  相似文献   

12.
The q-rung orthopair fuzzy sets are superior to intuitionistic fuzzy sets or Pythagorean fuzzy sets in expressing fuzzy and uncertain information. In this paper, some partitioned Bonferroni means (BMs) for q-rung orthopair fuzzy values have been developed. First, the q-rung orthopair fuzzy partitioned BM (q-ROFPBM) operator and the q-rung orthopair fuzzy partitioned geometric BM (q-ROFPGBM) operator are developed. Some desirable properties and some special cases of the new aggregation operators have been studied. The q-rung orthopair fuzzy weighted partitioned BM (q-ROFWPBM) operator and the q-rung orthopair fuzzy partitioned geometric weighted BM (q-ROFPGWBM) operator are also developed. Then, a new multiple-attribute decision-making method based on the q-ROFWPBM (q-ROFPGWBM) operator is proposed. Finally, a numerical example of investment company selection problem is given to illustrate feasibility and practical advantages of the new method.  相似文献   

13.
1∶25万数据库是国家测绘局继1∶100万数据库建立后的又一个大型的空间数据库,自从1998年被建成后广泛应用于国民经济各个部门,对它两次更新后,用户最关心它更新前后数据发生了什么变化,所以对数据变化的研究便尤为重要。本文通过对1∶25万数据库更新前后的地名利用空间分析和统计分析进行了定量的对比,从中探索地名变化的规律。为以后数据库地名的有效更新提供有力的参考。  相似文献   

14.
基于图象纹理分析的纱线质量检测   总被引:4,自引:0,他引:4  
李晓昆 《计算机工程》1999,25(4):55-56,62
为了使纱线质量检测自动化,提出一个高效的基于纹是分析的自动判别算法。  相似文献   

15.
对随机系数自回归模型的变均值点进行在线监测时, 如果变均值点的位置远离开始监测点, 则平均地说, 需要较长的运行时间方能检测到该变均值点. 为此, 笔者引进一个窗宽参数, 提出了一种改进的在线监测方法. 给出了监测统计量在原假设下的极限分布, 并证明了此方法的一致性. 模拟结果显示新方法明显优于已有的方法. 最后将该方法应用于两组股票价格均值点的监测问题中, 说明了方法的有效性.  相似文献   

16.
设计了一种腭裂语音的声韵母切分算法。通过主观的波形测试和客观的F检验及t检验,证明了腭裂语音与正常语音具有显著性差异。定义声母具有清音音素特性的音节为I类音节,声母具有浊音音素特性的音节为II类音节。首先基于层次聚类模型自动判别I类、II类音节,然后定义类浊音权重函数和类清音概率函数,实现I类音节的声韵母一级切分,再通过短时自相关函数峰值个数的一阶微分实现I类音节声韵母的二级切分。基于声韵母波形差异性,检测短时自相关函数的能量跳变点,实现II类音节的声韵母切分。通过大样本实验,结果表明提出的腭裂语音声韵母自动判别算法具有较高的正确率,I类音节的正确率达到90.72%,II类音节的正确率为92.90%。  相似文献   

17.
针对目前大多数方面级情感分析方法存在着没有重点关注局部上下文中关键词特征的问题.本文提出了一种基于局部上下文关键词特征提取及增强的方面级情感分析模型LCPM (local context pos mask).首先提出了局部上下文词性掩码机制,提取方面词周围重要词的特征,减少噪声词的干扰.其次对损失函数进行修改,让模型重点关注与方面词有关的局部上下文关键词特征,提升模型情感分类的表现.最后设计了一种门控机制,模型可以动态学习权重系数,给局部上下文关键词特征和全局上下文特征分配不同的权重系数.在4个公开数据集上的实验结果表明,与现有的方面级情感分析模型相比,准确率和MF1值都有提高,验证了局部上下文关键词提取及增强的有效性,在方面级情感分析任务上有较大的应用价值.  相似文献   

18.
In many cases, simulation is used to compare several scheduling strategies that may be applied to a system (considered as possible scenarios), with regard to several performance criteria. The simulation study of dispatching rules to job shop systems is a classical example. Unfortunately, simulation runs provide various tables of data, which can be difficult to read and to interpret. We discuss the use of multiple correspondence analysis to address this problem. This multivariate statistical technique allows certain relations between variables to be pointed out. The graphical overview of the available information which is provided facilitates the results interpretation and the comparison of strategies. To illustrate this approach, multiple correspondence analysis is used to study the application of well known dispatching rules to a simplified now shop.  相似文献   

19.
针对现有计算机视觉、图形学、信号处理、数字图像处理、应用光学等领域无法通过现有成像模型与装置及计算方法获取足够目标场景信息的难题,计算摄像学研究提出新的成像机制与对应的计算重构方法,在光信号观测领域另辟蹊径,创新性地将视觉信息处理与计算前移至成像过程,从而极大地提高了信息优化计算的自由度,能够在维度、尺度与分辨率上实现质的突破,从而观测到传统成像系统看不清与看不见的场景信息.本文沿着计算摄像学思路、方法与目标三条主线,对国内外研究现状进行分析与综述,期望能够帮助读者更快地了解及进入相关研究.  相似文献   

20.
This article utilises a dynamic model of unicycles to address the convergence of vehicle formation about closed convex curves. A novel curve extension method, extending the target loop along the vector from the loop centre to the point on the loop, is proposed to construct a family of level curves and the existence of a loop function on a tubular-like neighbourhood is proved by referring to the tubular neighbourhood theorem. Path following control is derived based on the loop function which incorporated into the arc-length function to propose the solution to coordinated formation control. We show how backstepping technique, Lyapunov-based theory and graph theory can be combined together to construct the coordinated path following controller under the bidirectional commutation topology. It is proved that the designed cooperative control system is asymptotically stable if the graph is connected. The proposed method is effective for a skewed superellipse, which is a type of curve that includes circles, ellipses and rounded parallelograms.  相似文献   

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