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11.
In Bayesian machine learning, conjugate priors are popular, mostly due to mathematical convenience. In this paper, we show that there are deeper reasons for choosing a conjugate prior. Specifically, we formulate the conjugate prior in the form of Bregman divergence and show that it is the inherent geometry of conjugate priors that makes them appropriate and intuitive. This geometric interpretation allows one to view the hyperparameters of conjugate priors as the effective sample points, thus providing additional intuition. We use this geometric understanding of conjugate priors to derive the hyperparameters and expression of the prior used to couple the generative and discriminative components of a hybrid model for semi-supervised learning.  相似文献   
12.
采用溶胶-凝胶方法制备了Ti(1-x)CoxO2样品。研究了不同的热处理温度和掺杂浓度对样品晶型和颗粒尺寸的影响。样品400℃热处理呈锐钛矿相,600℃转变为全红石相并且晶粒尺寸明显增大。掺杂对晶型没有影响,但是随掺杂量的增大晶格常数减小。  相似文献   
13.
Presents a comment on "Psychological treatments" (see record 2004-21168-001) by D. H. Barlow. Barlow proposed that we distinguish between the terms "treatment" and "psychotherapy." The author believes that not only is the distinction unnecessary, but that its implications could have negative consequences for the field of clinical psychology. It is the proposed distinguishing feature that treatments are "specifically tailored to the pathological process that is causing the impairment and distress" that is most problematic. Clinical psychology does not need a distinction that further exacerbates the split between researchers and practitioners. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
针对传统泣塑模CAD系统的缺陷,提出并分析了新型注塑模系统的总体设计方案和3DMCAD/CAM系统构建语言,由此实现了柔性化注塑模CAD系统,包括模架、抽芯机构、浇口套等机构及其孔型的信息获取、自动生成、更新和删除。  相似文献   
15.
The principles of macroergonomics and the laws of ergodynamics are reviewed. The theories of mutual adaptation and transformation dynamics are presented as a complex basis of the ergodynamics, and they are offered as paradigms for macroergonomic evaluation and design of sociotechnical or human‐machine‐environment decision‐making systems (HMES). Criteria and factors of decision‐making efficiency are studied for different cognitive strategies and their transformations in the course of long‐term training and short‐term decision making in emergencies. Sample system criteria and design guidelines, based on the results of both laboratory studies and actual research and design applications, are provided. A combination of macroergonomics and ergodynamics helps ergonomists to meet rapidly growing requirements of practice and overcome a narrow approach to the workstations analysis when a broader view of complex multilevel system leads to success and instead of traditional static approach the analysis of transformations in technologies, management structures, and work skills is needed.  相似文献   
16.
17.
The binary hypercube Q n has a small diameter, but a relatively large number of links. Because of this, efforts have been made to determine the maximum number of links that can be deleted without increasing the diameter. However, the resulting networks are not vertex‐symmetric. We propose a family of vertex‐symmetric spanning subnetworks of Q n , whose diameter differs from that of Q n by only a small constant factor. When n=2k, the cube‐connected cycles network of dimension n is a vertex‐symmetric spanning subnetwork of Q n+lg n . By selectively adding hypercube links, we obtain a degree 6 vertex‐symmetric network with diameter 3n/2. We also introduce a vertex‐symmetric spanning subnetwork of Q n−1 with degree log2 n, diameter 3n/2−2, log2 n‐connectivity and maximal fault tolerance. This network hosts Q n−1 with dilation 2(log2 n)−1. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
18.
Editorial     
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19.
Entry costs to home ownership have been rising in Australia since the mid‐1950s but home ownership rates had not fallen by the mid‐1980s. Drawing from a national life history survey carried out in 1986–87, this paper shows that median ages for first time home buying have been declining among successive cohorts over the post‐war era. The paradox of rising entry costs and earlier home buying may be explained by rising labour force participation among women immediately after marriage and awareness of the increasing financial returns from long‐term home ownership. Among the later cohorts, early entry to home ownership appears to have been associated particularly strongly with wives' employment after marriage and husbands' incomes. The findings suggest that access to home ownership in the future may be increasingly limited to young adults having high household incomes.  相似文献   
20.
The properties of mixed monolayer films of photochromic indolinospiropyrans and poly(methylmethacrylate) (PMMA), poly(vinyl stearate) (PVSt), and poly(2-vinyl pyridine) (P2VP) have been studied. It was found that reversible photoinduced changes in monolayer surface-pressure with time occurred in collapsed systems and in mixed films in which the photochrome had been forced out of the polymer monolayer. Mixed films of P2VP and a spiropyran of particular structure could have their inherent stability increased under the action of ultraviolet irradiation on aqueous subphases. This effect appeared to be related to the formation of a physically crosslinked photomerocyanine-polymer two-dimensional network.  相似文献   
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