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91.
Recently, interest about model discrimination has been focused on methods based on model estimation. Due to the problem of model aliasing, several criteria have been proposed aimed at assessing the capacity of a design for model discrimination. Three of these measures, along with a new criterion that combines them and assesses the overall discrimination capacity of a design, are implemented to evaluate a class of 27-run orthogonal arrays in three levels.  相似文献   
92.
The orthogonal arrays with mixed levels have become widely used in fractional factorial designs. It is highly desirable to know when such designs with resolution III or IV have clear two-factor interaction components (2fic’s). In this paper, we give a complete classification of the existence of clear 2fic’s in regular 2 m 4 n designs with resolution III or IV. The necessary and sufficient conditions for a 2 m 4 n design to have clear 2fic’s are given. Also, 2 m 4 n designs of 32 runs with the most clear 2fic’s are given for n = 1,2.   相似文献   
93.
对二元二次多项式回归模型进行预先正交化处理,提出使用因子空间的N等份的格子设计的观点,推导出了信息矩阵的一般性结构,并给出了该设计的非退化条件及其最小二乘估计和对应的协方差矩阵。  相似文献   
94.
数字高清晰度电视地面广播COFDM传输方案   总被引:1,自引:0,他引:1  
数字高清晰度电视是新一代电视的发展方向,常用的传输方案是编玛正交频分复用(COFDM)方案和大联盟(GA)的残留边带调制(VSB)方案。文中介绍了在于COFDM的数字高清晰度电视全数字发送部分的基本传输方案和硬件实现,分析了误码率等性能,并给出了实验结果。  相似文献   
95.
为了研究经提取并纯化后的墨鱼墨中多酚氧化酶(PPO)的酶活性及其在红茶饮料加工中的应用,以新鲜墨鱼墨囊为PPO提取原料,用p H7.2磷酸盐缓冲液初步提纯,粗酶液又经饱和度为30%-80%硫酸铵分级沉淀,得到纯化倍数为3.09,酶活性达到199450u的PPO粗酶液。为探寻墨囊PPO在红茶饮料加工中的最佳工艺方案,通过单因素实验和正交试验以及感官评定试验,确定其在红茶饮料加工中应用的最佳工艺条件为:酶添加量为0.05%(m/v),反应温度为50℃,反应体系pH为8.0。  相似文献   
96.
Nested orthogonal arrays have been used in the design of an experimental setup consisting of two experiments, the expensive one of higher accuracy being nested in a larger and relatively less expensive one of lower accuracy. In this paper, we provide new methods for constructing two types of nested orthogonal arrays.  相似文献   
97.
We propose to discuss at length several examples from standard text books. All of these examples deal with analysis of covariance (ANCOVA) models and related analyses of data. We intend to capitalize on our understanding of optimal covariate designs (OCDs) in different ANCOVA models and re-visit these examples with a view to suggest optimal/nearly optimal designs for estimation of the covariate parameter(s). As we will see, for some examples our task is very much routine but for others, it is indeed a highly non trivial exercise.

?We intent to cover a total of six examples—divided in two parts. This is Part I—dealing with two examples.  相似文献   
98.
基于量子密钥分配协议是目前实现密钥分配最安全的方法,两个三态量子位组成的复合系统中存在一组正交直积态,它可以表现出非定域性。该文提出了一个建立在该系统的非定域性基础上的量子密钥分配协议,协议双方通过交换量子位和集体测量建立起共享的密钥。量子力学的基本原理保证了该协议是无条件安全的,没有第三方可以窃取密钥而不被发现。该协议不需要纠缠态,也不需要做任何量子操作。因此,它更容易在实践中实现,同时具有更高的可靠性与健壮性。  相似文献   
99.
This paper introduces a new class of designs called equi-neighboured designs. An equineighboured design has the property that every unordered pair of treatments occurs as nearest neighbours equally frequently at every level. These designs are defined in Section 4 and shown to be balanced when neighbouring observations are correlated. Some equineighboured designs are constructed using a complete set of orthogonal Latin squares. Cyclic equineighboured designs are also defined.  相似文献   
100.
This paper is concerned with estimating a mixing density g using a random sample from the mixture distribution f(x)=∫f x | θ)g(θ)dθ where f(· | θ) is a known discrete exponen tial family of density functions. Recently two techniques for estimating g have been proposed. The first uses Fourier analysis and the method of kernels and the second uses orthogonal polynomials. It is known that the first technique is capable of yielding estimators that achieve (or almost achieve) the minimax convergence rate. We show that this is true for the technique based on orthogonal polynomials as well. The practical implementation of these estimators is also addressed. Computer experiments indicate that the kernel estimators give somewhat disappoint ing finite sample results. However, the orthogonal polynomial estimators appear to do much better. To improve on the finite sample performance of the orthogonal polynomial estimators, a way of estimating the optimal truncation parameter is proposed. The resultant estimators retain the convergence rates of the previous estimators and a Monte Carlo finite sample study reveals that they perform well relative to the ones based on the optimal truncation parameter.  相似文献   
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