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101.
102.
Mixtures of factor analyzers is a useful model-based clustering method which can avoid the curse of dimensionality in high-dimensional clustering. However, this approach is sensitive to both diverse non-normalities of marginal variables and outliers, which are commonly observed in multivariate experiments. We propose mixtures of Gaussian copula factor analyzers (MGCFA) for clustering high-dimensional clustering. This model has two advantages; (1) it allows different marginal distributions to facilitate fitting flexibility of the mixture model, (2) it can avoid the curse of dimensionality by embedding the factor-analytic structure in the component-correlation matrices of the mixture distribution.An EM algorithm is developed for the fitting of MGCFA. The proposed method is free of the curse of dimensionality and allows any parametric marginal distribution which fits best to the data. It is applied to both synthetic data and a microarray gene expression data for clustering and shows its better performance over several existing methods.  相似文献   
103.
以泰州某大跨度连续梁桥的静动载试验为例,建立ANSYS和桥梁博士模型进行静动力有限元数值计算。将试验结果与模型计算值进行比较,试验结果表明,该桥结构刚度和承载能力满足设计要求。  相似文献   
104.
This paper reports results from recent Eurofound research on the impact of the crisis on industrial relations and working conditions in Europe, based on the output of Eurofound's European Working Conditions Observatory and European Industrial Relations Observatory and data from the European Working Conditions Survey. Overall, the crisis – even if it is sometimes difficult to separate the effect of the crisis from megatrends in working conditions and industrial relations – seems to have had an impact on both domains. With reference to industrial relations, the impact of the crisis has influenced actors, processes, and outcomes. Regarding working conditions, the results appear to be in line with the literature on the topic, which relates the crisis to an increase in job insecurity, a decrease in work intensity, in working hours, and in anti-social working time arrangements, and a general improvement in terms of health risks and related outcomes.  相似文献   
105.
本文根据地质力学和岩体结构力学原理,探讨水平扭剪应力场在大裂缝系统形成、转化和分布中的重要控制作用及其物理模型.文中认为,大裂缝系统是较大的直压型裂缝网络与扭剪型裂缝网络叠加的产物,主要分布在较强的水平扭剪应力和术平直压应力复合作用的区块;水平扭剪应力场是改造和控制大裂缝网络结构异向性的最重要因素。这为研究和勘探较大的隐伏裂缝系统,提供了新的成藏模式和理论依据。  相似文献   
106.
“重陆轻海”与“通洋裕国”之海洋观刍议   总被引:1,自引:0,他引:1  
明清两朝正处于世界性海洋历史发展的"千古变局"时代,但统治者沿袭传统模式,在立国思想上"重农抑商"、"重陆轻海",在国防战略上以"禁海"代替海防,禁海迁界、"守土防御",反映其海洋观念的淡薄;而东南沿海地方官员,尤其郑成功"通洋裕国"思想的提出和实践,显露出"以商立国",向海洋空间发展的意涵;传统时代"重陆轻海"与"通洋裕国"所反映的海洋观念,对国家民族发展的影响在某种程度上可以忽略不计,但大航海时代,海洋作为人类的第二生存空间影响到世界历史走向和发展格局时,"重陆轻海"观念所带来的深层影响会因此而改变国家和民族的命运。  相似文献   
107.
While the literature has indeed confirmed a general tendency linking small and medium enterprises (SMEs) to a dynamic of greater job creation, there is little available evidence on what has happened to job quality since the financial crisis. Through a representative sample of 5311 employees in 2008 (first year of job destruction) and 4925 employees in 2010 (last year for which data were available), and using a two-stage structural equation model, this article empirically analyses the multidimensional determinants of job quality, by enterprise-size class, in Spain. The research has revealed three main results. First, job quality in Spain improved in all enterprises, regardless of their size, during the early years of the recession. Second, the greatest improvements were found in SMEs. Although job quality was already better in SMEs than in large enterprises in 2008, the differences between them subsequently widened. Third, this accelerated divergence was explained by the following dimensions: working conditions, work intensity, health and safety at work, and work–life balance. These dimensions were much more positive in SMEs. Employment-related public policy should therefore focus more specifically on SMEs. There are two reasons for this. First, despite the recession, SMEs have shown themselves to be key factors in the explanation of job quality. Second, by making changes to their value generation model, they could continue to drive the creation of better quality jobs.  相似文献   
108.
Abstract. Spatial Cox point processes is a natural framework for quantifying the various sources of variation governing the spatial distribution of rain forest trees. We introduce a general criterion for variance decomposition for spatial Cox processes and apply it to specific Cox process models with additive or log linear random intensity functions. We moreover consider a new and flexible class of pair correlation function models given in terms of normal variance mixture covariance functions. The proposed methodology is applied to point pattern data sets of locations of tropical rain forest trees.  相似文献   
109.
With the increasing importance of self-help groups, professionals need to augment their understanding of how groups work in order to help clients make effective use of them. Three conceptual frameworks-social networks, social learning and cognitive theory-explain the basic psychosocial processes of self-help groups. Practice implications indicate how clients can benefit from self-help groups and suggest how professionals might enable their clients to realize the full benefits of participation in them.  相似文献   
110.
Abstract

It has been suggested that psychological stress is one of the reasons for the high morbidity among unemployed people in Western countries. The same may apply to the well-documented high mortality. It would be expected that increased levels of biological stress would be found in these people. In the present study a sample of 310 long-term unemployed people from Norway was followed for 2 years. Psychologcal stress was assessed by medical examination and by the psychometric tests GHQ-28 and HSCL-30, the latter compared with a reference population of employed people. Serum levels of cortisol, prolactin and testosterone, together with immunoglobulins IgA, IgG and IgM, were compared with working controls. The unemployed had a high level of psychological distress at the first examination, the sanie for men and women. At the 2-year follow up distress was reduced by re-employment. This fits the ‘causation hypothesis' which explains the high distress level as caused by unemployment. The other direction of causation, ‘the selection hypothesis', assuming that distressed persons have an increased chance of continuous unemployment, was also confirmed in the present study. As for biological stress, significant differences were not found between the unemployment, the re-employed and the working controls.  相似文献   
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