首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 171 毫秒
1.
在可见光域632.8 nm光波段,首次研制出Ti∶LiNbO3质子交换光波导型偏振器.同时,给出了波导型偏振器参数测试装置.在理论上,利用物理光学和波导色散理论分析与计算了这种偏振器的消光比,分析了影响器件性能的各种因素.理论计算与实验结果符合良好.  相似文献   

2.
正交试验设计方法在汽车制动系统试验设计中的应用   总被引:5,自引:0,他引:5  
在新产品开发过程中,人们常需要了解各种因素对产品或产品的性能、成本、产量等指标的影响。实际问题中影响这些指标的因素往往很多,要想完成一个全因素组合配置试验以期了解这些影响常常是极浪费和不现实的。本结合HFC1061液压制动系统试验设计与分析的过程,总结正交试验设计在应用过程中影响因素及其位级规范化、试验设计和数据分析等几个主要步骤的实施方法与要求。  相似文献   

3.
贴膜位置的偏移是轻触薄膜开关出现不良品的主要因素之一,位置偏移量的大小在很大程度上取决于用来检查贴膜位置偏移的位置测量装置的测量精度.通过参数设计的方法,系统分析影响位置测量装置测量精度的影响因素,依据L_(18)(2~1×3~7)正交表安排正交试验,将贴膜上20个金属弹片两两之间的距离作为信号因子,通过比例式校准模型分别计算每次试验的SN比和比例系数,分析最优的因子水平组合.研究表明,优化后的位置检查装置识别能力得到了明显的改善,最适合条件的位置检查装置具有更好的测量精确度.  相似文献   

4.
本文对于炼油装置所安排的正交试验过程,利用正交多项式确定出各影响试验指标的因素对试验指标的效应函数,从而求出所有因素对试验指标的效应函数多项式.利用多项式来优化装置操作条件.  相似文献   

5.
调查表可重复性信度研究方法   总被引:5,自引:0,他引:5  
本文结合安庆市1992年部分乡镇卫技人员二次心态调查资料,介绍了一种调查表内计量测量的条目的可重复性信度分析方法──方差分析法,以及定性测量的条目两次调查结果一致度分析方法,对影响调查表可重复性的主要因素进行了讨论,强调了调查表信度分析的意义这对于我们在大型现场研究中提高调查表设计能力,提高测量的效度与精度有重要理论指导意义.  相似文献   

6.
上海世博会"城市让生活更美好"的主题具有丰富的内涵,城市居民的生活美好水平可通过与周边乡村居民的生活比较进行测量,其影响因素有富裕、和谐、美化、安全等。在设计生活美好指数评价指标和影响因素测量指标的基础上,构建指数测量和影响因素分析的二阶段模型,并以2007年中国31省市的地市级城市的截面数据为样本,采用改进的模糊积分和格兰杰检验方法进行实证分析,得出"城市让生活更美好"命题成立,而对城市美好生活具有重要有利影响的因素主要是城市和谐、城市美化、城市开放和城市进步的结论。  相似文献   

7.
本文对我国测量通货膨胀的主要指标全国零售物价总指数进行了相关因素分析,并在此基础上建立了零售物价总指数预测的数学模型.  相似文献   

8.
利用分位数回归模型探讨了原油价格、道琼斯指数、美元汇率、上证指数和利率对国内黄金价格的影响.实证分析结果表明在不同分位数水平上各因素对黄金价格的影响不一样.分位数回归能够从历史数据中挖掘出更多的信息,更有利于投资者了解影响黄金价格波动的因素从而做出更好的决策.  相似文献   

9.
榆树林油田CO_2吞吐采油目标井优选方法研究   总被引:2,自引:2,他引:0  
CO_2吞吐是开发低渗透油田的有效方法之一,但进行CO_2吞吐前目标井的优选是关键步骤,它直接关系到CO_2吞吐措施的成败.首先分析了剩余油饱和度、油井含水率、油层厚度、渗透率、孔隙度、井底流压各因素对CO_2吞吐效果的影响,从而建立评价指标,然后利用层次分析方法确定各单因素的合理权重,最后根据模糊综合评判法优选出树11Y68-57和树11Y67-611两口油井适宜CO_2吞吐.优选出的油井具有良好的的油效果,表明该方法是正确可行的,具有一定的推广价值.  相似文献   

10.
降低回路电阻值技术措施的优化   总被引:1,自引:1,他引:0  
引言 断路器的回路电阻值是评价电器连接接触质量的重要指标.它是一个受多种因素影响之随机变量.长期以来没能在充分可靠的基础上,找出满意的改进措施.我们用正交实验及方差分析方法,在这方面进行了一些工作.(文2) 主要是通过多次 PDCA循环,完成了确定影响接触质量稳定性的关键部位,对关键部位考察主要影响因素并提出改进措施.因而取得了提高质量、减少返修工作量、提高一次合格率等效益.在此基础上我们又对L27内正交表中每种可控因素及水平搭配条件,增加在不同时效及操作次数条件下的测量数据,并进行信噪比分析,以确定受各种因素干扰影响…  相似文献   

11.
The problems of estimating ratio of scale parameters of two distributions with unknown location parameters are treated from a decision-theoretic point of view. The paper provides the procedures improving on the usual ratio estimator under strictly convex loss functions and the general distributions having monotone likelihood ratio properties. In particular,double shrinkage improved estimators which utilize both of estimators of two location parameters are presented. Under order restrictions on the scale parameters, various improvements for estimation of the ratio and the scale parameters are also considered. These results are applied to normal, lognormal, exponential and pareto distributions. Finally, a multivariate extension is given for ratio of covariance matrices.  相似文献   

12.
We study the bandwidth and the pathwidth of multi-dimensional grids. It can be shown for grids, that these two parameters are equal to a more basic graph parameter, the vertex boundary width. Using this fact, we determine the bandwidth and the pathwidth of three-dimensional grids, which were known only for the cubic case. As a by-product, we also determine the two parameters of multi-dimensional grids with relatively large maximum factors.  相似文献   

13.
针对多响应参数优化问题,考虑响应间相关性和可控因子波动的影响,提出了一种基于似无关回归的多元稳健损失函数方法。首先采用似无关回归对模型拟合和过程优化中的相关参数进行估计,更有效地利用响应间相关性信息;然后利用给定点处梯度信息来估计可控因子波动对过程稳健性的影响。算例表明,当响应间存在相关性时,与最小二乘方法相比,采用似无关回归拟合的响应曲面模型精度更高;与传统质量损失函数相比,在采用相同质量成本矩阵时,采用稳健损失函数方法得到的最优解处期望质量损失更小。  相似文献   

14.
We consider the estimation of the ratio of the scale parameters of two independent two-parameter exponential distributions with unknown location parameters. It is shown that the best affine equivariant estimator (BAEE) is inadmissible under any loss function from a large class of bowl-shaped loss functions. Two new classes of improved estimators are obtained. Some values of the risk functions of the BAEE and two improved estimators are evaluated for two particular loss functions. Our results are parallel to those of Zidek (1973, Ann. Statist., 1, 264–278), who derived a class of estimators that dominate the BAEE of the scale parameter of a two-parameter exponential distribution.  相似文献   

15.
Polygon transformations based on taking the apices of similar triangles constructed on the sides of an initial polygon are analyzed as well as the limit polygons obtained by iteratively applying such transformations. In contrast to other approaches, this is done with respect to two construction parameters representing a base angle and an apex perpendicular subdivision ratio. Furthermore, a combined transformation leading to circulant Hermitian matrices is proposed, which eliminates the rotational effect of the basic transformation. A finite set of characteristic parameter subdomains is derived for which the sequence converges to specific eigenpolygons. Otherwise, limit polygons turn out to be linear combinations of up to three eigenpolygons. This leads to a full classification of circulant Hermitian similar triangles based polygon transformations and their limit polygons. As a byproduct classical results as Napoleon’s theorem and the Petr-Douglas-Neumann theorem can be easily deduced.  相似文献   

16.
基于测量质量损失函数的控制图控制界限的优化   总被引:1,自引:0,他引:1  
控制界限和抽样间隔是控制图的两个基本参数。常规控制图是基于3σ原理确定的控制界限,该控制界限是在大量试验基础上依据经验确定的,并没有精确的公式推导.对于抽样间隔,常规控制图也没有明确的规定。田口博士的质量损失函数可以很好的解决质量经济性方面的一些问题.利用田口博士的理论,通过确定适宜的二次测量质量损失函数,可以确定控制图的最佳控制界限和最佳抽样间隔.文章简要介绍了常规控制图原理和田口博士的质量损失函数,重点叙述了田口博士反馈控制系统的测量质量损失函数,在此基础上,研究了控制图最佳控制界限和最佳抽样间隔,并且通过具体实例验证了该控制图良好的经济性.  相似文献   

17.
王宁  白静  张新立 《经济数学》2017,34(1):72-76
在前人相关研究基础上,将主体异质性等更符合实际的影响因素引入到风险联合投资演化博弈模型中,求出了模型的演化稳定策略,并对影响演化稳定策略的相关因素进行了分析,博弈一方的合作策略选择视对方的合作均衡策略而定,但联合投资的合作行为终将演化为一博弈方选择不合作策略而终止.主体的异质性与单位冲突成本收益对促进双方都选择合作策略造成很大影响,异质性程度差异程度越大,单位冲突成本收益越小,联合投资成功的可能性就越大,合作行为也会因双方遵守合约契约而得到长期稳定的维持.  相似文献   

18.
The main object of this paper is to discuss the Bayes estimation of the regression coefficients in the elliptically distributed simple regression model with measurement errors. The posterior distribution for the line parameters is obtained in a closed form, considering the following: the ratio of the error variances is known, informative prior distribution for the error variance, and non-informative prior distributions for the regression coefficients and for the incidental parameters. We proved that the posterior distribution of the regression coefficients has at most two real modes. Situations with a single mode are more likely than those with two modes, especially in large samples. The precision of the modal estimators is studied by deriving the Hessian matrix, which although complicated can be computed numerically. The posterior mean is estimated by using the Gibbs sampling algorithm and approximations by normal distributions. The results are applied to a real data set and connections with results in the literature are reported.  相似文献   

19.
In this study, the problem of developing simple dynamic models of an anaerobic digestion process is tackled using an identification procedure which proceeds in several consecutive steps. Starting from sets of experimental data describing the time evolution of several key component concentrations, i.e. biomass(es), substrates and products, the minimal number of macroscopic bioreactions required to represent the data at hand, as well as the parameters of the associated stoichiometry matrix, are determined using maximum likelihood principal component analysis. Then, the structure of the kinetic laws, together with their parameters, are identified using likelihood ratio tests to navigate through the branches of decision trees made of various kinetic structures. The effectiveness of the modelling procedure is illustrated with a simulated example of anaerobic digestion. As usual sensors only provide aggregate measurements of the component concentration, a deeper investigation of practical identifiability is achieved in relation with the influence of measurement errors.  相似文献   

20.
Optical waveguide polarizer at 632.8 nm was fabricated for the first time using proton exchange Ti:LiNbO3. The setup measuring the characteristic parameters of the polarizer was given. The extinction ratio of the polarizer was theoretically analyzed and calculated by means of physical optics and dispersion theory for waveguide. Various factors affecting the device performance are analyzed. Theoretical calculations are in good agreement with the experimental results.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号