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101.
An experimenter in the field of cloud seeding describes aspects of experiments which he would like statisticians to take into account and suggects Problems which he would like statisficians solve.  相似文献   
102.
In this paper, conditions for a set of points to form a rotatable design of order four have been worked out. These condi- tions form the basis for obtaining a set of rotatable designs of order four.  相似文献   
103.
从研究SAR的海洋遥感探测重要性和基本特点出发,概述了SAR系统的海洋遥感探测技术所涉及的主要研究内容,针对海洋环境要素分布的随机性和时变性,研究了海面微波散射特性和SAR的海面成像机理,给出了研究结果;分析了SAR系统主要特点,提出研究包括系统的宽测绘带特性和雷达的弱信号获取、海面精确成像算法和时空相关性等方面;同时探讨了海洋目标检测的技术途径,以满足SAR系统海洋观测应用的需要.  相似文献   
104.
为阐述化学研究中必然性与偶然性的关系,分析了化学研究中归纳推理和机遇的重要性,并讨论了化学研究中机遇的产生根源和捕捉方法。结果表明,化学研究中既要重视其必然性,树立必胜信心,通过归功推理,探索化学的奥秘;又要重视其偶然性,抓住机遇,尽早攻克难关。  相似文献   
105.
In this article optimality of experimental design for fitting a lower-order polynomial to a higher order response function for the situation in which observations may be subject to shift in means as well as in variances is considered. It is found that Karson, Manson and Hader‘s (1969) optimum designs provide pro-tection, in some sense, against model inadequacies even when observations are subject to shift in means and variances.  相似文献   
106.
针对大坡度桥梁预制梁架设,以阿尔及利亚东西高速公路(中段)18公里桥为例,在原有架桥机基础上进行了改装设计,并采取其它工程措施保证了架梁的速度、质量和安全,使大坡度T梁架设工作得以顺利完成。  相似文献   
107.
通过调查问卷、个案采访、座谈等方式对某大学学生干部的心理压力状况进行分析,并提出调适建议。  相似文献   
108.
Numerous scholars have argued that we are currently in a post “tattoo renaissance” era wherein the practice has increasingly become a legitimate art form accepted by the American middle class. In order to facilitate this cultural transition, tattooed people legitimize their own tattoos through various narratives that ascribe deep semantic meaning to their images and words. Pulling from twenty-two in-depth interviews with tattoo removal clinicians, tattoo artists, people who regret at least one of their current tattoos, and people who have had their tattoos removed or altered, this paper contributes to the literature on the meaning and significance of tattoos in the lives of 21st century Americans. In particular, we aim to showcase that, in the current cultural context, wherein people feel a need to justify their tattoos with a level of profound symbolic meaning, tattoo regret abounds in a form distinct from that of previous generations. Drawing from a post-structuralist framework which understands tattoos as symbols, we discuss tattoo narratives as pervasive normative expectations and explore how people face potential dilemmas when they lack them, as well as when they subscribe static and absolute meanings to the words and images depicted in their body art. These narratives, and accordingly the tattoos themselves, become problematic as a result of the inability of tattoos to function beyond their capacity as symbolic representations. When people cannot reconcile or transcend the dynamic and relative nature of their tattoos’ symbolic meanings, they feel regretful and sometimes opt for tattoo cover-ups or removals.  相似文献   
109.
In response surface designs, it is not usually easy to handle the moment matrix X'X, especially for higher orders. This paper presents a method in which the moment matrix of a response surface of any order can be standardized, i.e., X'X splits into a diagonal matrix consisting of sub-matrices of lower order. This eases the calculation of the determinant and the inverse of X'X. The method has been illustrated with applications to second, third and fourth order response surfaces.  相似文献   
110.
Most experimental material in agriculture and industry is heterogeneous in nature and therefore its statistical analysis benefits from blocking. Many experiments are restricted in time or space, and again blocking is useful. This paper adopts the idea of orthogonal blocking of Box & Hunter (1957) and applies it to optimal blocking designs. This approach is then compared with the determinant-based approach described in the literature for constructing block designs.  相似文献   
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