Using orthogonal array for constructing three-level search designs

We consider the problem of constructing search designs for 3^m factorial designs. By using projection properties of some three-level orthogonal arrays, some search designs are obtained for 3 ? m ? 11. The new obtained orthogonal search designs are capable of searching and identifying up to four two-factor interactions and estimating them along with the general mean and main effects. The resulted designs have very high searching probabilities; it means that besides the well-known orthogonal structure, they have high ability in searching the true effects.     

C语言“指针”教学经验谈

在C语言的教学中,指针概念的教学一直就是C语言的教学重点和难点,指针已成为学习和掌握C语言的一大障碍.从硬件角度、图示方法及举例选题三个方面介绍了C语言指针教学中的体会.     

An orthogonal arrays approach to robust parameter designs methodology

Robust parameter design methodology was originally introduced by Taguchi [14 Taguchi, G. 1986. Introduction to Quality Engineering: Designing Quality Into Products and Process, Tokyo: Asian Productivity Organization.  [Google Scholar]] as an engineering methodology for quality improvement of products and processes. A robust design of a system is one in which two different types of factors are varied; control factors and noise factors. Control factors are variables with levels that are adjustable, whereas noise factors are variables with levels that are hard or impossible to control during normal conditions, such as environmental conditions and raw-material properties. Robust parameter design aims at the reduction of process variation by properly selecting the levels of control factors so that the process becomes insensitive to changes in noise factors. Taguchi [14 Taguchi, G. 1986. Introduction to Quality Engineering: Designing Quality Into Products and Process, Tokyo: Asian Productivity Organization.  [Google Scholar] 15 Taguchi, G. 1987. System of Experimental Design, Vol. I and II, New York: UNIPUB.  [Google Scholar]] proposed the use of crossed arrays (inner–outer arrays) for robust parameter design. A crossed array is the cross-product of an orthogonal array (OA) involving control factors (inner array) and an OA involving noise factors (outer array). Objecting to the run size and the flexibility of crossed arrays, several authors combined control and noise factors in a single design matrix, which is called a combined array, instead of crossed arrays. In this framework, we present the use of OAs in Taguchi's methodology as a useful tool for designing robust parameter designs with economical run size.     

Orthogonal Arrays for the Estimation of Global Sensitivity Indices Based on ANOVA High-Dimensional Model Representation

We present an efficient new approach to estimate global sensitivity indices based on ANOVA high-dimensional model representation. The method makes use of the properties of orthogonal arrays and extend the results of Wang et al. (2010 Wang , X. , Tang , Y. , Chen , X. , Zhang , Y. ( 2010 ). Design of experiment in global sensitivity analysis based on ANOVA high-dimensional model representation . Communications in Statistics—Simulation and Computation 39 : 1183 – 1195 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) to a more general situation. A theorem is given to illustrate that both the non influential and significant sensitivity indices are well estimated. This new method offers higher sampling efficiency than those of Sobol and Saltelli. We test its performance on two different models, which are widely used in engineering and statistical areas.     

Constructing D-optimal symmetric stated preference discrete choice experiments

We give new constructions for DCEs in which all attributes have the same number of levels. These constructions use several combinatorial structures, such as orthogonal arrays, balanced incomplete block designs and Hadamard matrices. If we assume that only the main effects of the attributes are to be used to explain the results and that all attribute level combinations are equally attractive, we show that the constructed DCEs are D-optimal.     

Classification of three-level strength-3 arrays

Generalized aberration (GA) is one of the most frequently used criteria to quantify the suitability of an orthogonal array (OA) to be used as an experimental design. The two main motivations for GA are that it quantifies bias in a main-effects only model and that it is a good surrogate for estimation efficiencies of models with all the main effects and some two-factor interaction components. We demonstrate that these motivations are not appropriate for three-level OAs of strength 3 and we propose a direct classification with other criteria instead. To illustrate, we classified complete series of three-level strength-3 OAs with 27, 54 and 81 runs using the GA criterion, the rank of the matrix with two-factor interaction contrasts, the estimation efficiency of two-factor interactions, the projection estimation capacity, and a new model robustness criterion. For all of the series, we provide a list of admissible designs according to these criteria.     

新型PA高帧频摄像机的设计与实现

采用光敏二极管阵列固体图像传感器,设计研制了1000帧/s的高速PA摄像机,并对技术原理、PA图像传感器特点、连续和单次时序设计及图像传感器输出视频信号处理等方面作了介绍。PA视频摄像机可工作于连续和单次两种工作状态。采用纤维面板耦合,像素100×100;最小照度优于1.5 勒克斯,动态范围100倍。     

DDS阵列频率源技术研究

杂散抑制差和输出频率低是DDS的两大缺点,并且随着输出带宽的增加杂散性能更加恶化。传统的解决方法是采用更好的算法和改进DDS芯片本身的结构。该文在分析了DDS杂散性能和输出带宽相互制约的DDS阵列方法基础上,尝试了一种新的解决办法棗DDS阵列方法。同时还分析了这种方法的性能,并通过实验验证了其可行性。     

全自适应阵列中的逆QR分解算法

提出了一种在全自适应阵列中的逆ＱＲ分解算法，给出了它的Ｓｙｓｒｏｌｉｃ实现方法。该算法可以很容易地映射到Ｓｙｓｔｏｌｉｃ结构上，仅需一个Ｓｙｓｔｏｌｉｃ阵便能得到最佳权矢量。并且同ＱＲ分解算法一样，它是直接对数据矩阵进行处理，且变换采用酉阵，保持了很好的数值稳定性