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181.
182.
Fiona Simpson 《GeoJournal》2000,50(2-3):127-131
Ethnic minorities are facing increasing problems of social exclusion in Central and Eastern Europe. The complex nature of
the transition from socialism means that the institutional framework to support them is still being established. Whilst non-governmental
organisations (NGOs) have a crucial role to play in promoting a more inclusive society, through improving access to local
democratic structures for otherwise excluded groups and acting as fora for improved community participation throughout the
region, their development remains fraught with problems. Examination of the experiences of one such organisation, ETNO Agentura
based in northern Slovakia, provides an insight into the problems and opportunities arising as community representatives work
together to provide social support for ethnic minorities. The paper outlines key issues arising from the case of ETNO Agentura,
including difficulty in gaining access to supporting finance and securing long term financial viability, the lack of institutional
capacity of local authorities to become receptive to their views, and implicit socio-cultural barriers to ethnic minority
representation in community participation processes. Developing a fuller understanding of these problems and the measures
required to overcome them is a central part of establishing a more effective role for NGOs within post socialist societies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
183.
许志文 《华东地质学院学报》2000,23(1):87-89
介绍了对稀疏矩阵进行压缩存储时,稀疏矩阵相乘运算的基本思想和算法.在此基础上,探讨了避免矩阵中零元素相乘的无效操作,奠定了该算法的矩阵变换基础. 相似文献
184.
钱善皆 《中国天文和天体物理学报》2000,20(4)
以类星体0917+624中1989年5月观测到的IDV事件为实例,尝试提出一个4成分模型(1个稳定成分和 3个闪烁成分)以充分解释在 6 cm波长上观测到的偏振变化,包括流量和偏振流量的相关性和反相关性以及它们之间的快速转化.对于 20 cm波长上观测到的偏振变化,3成分模型(1个稳定成分和3个闪烁成分)已足以解释全部现象.文中提出的闪烁模型在解释IDV事件的偏振变化方面改进了以前的模型拟合. 相似文献
185.
利用基于自校正和CLEAN算法的现代VLBI混合成图技术,对Pearson等人于1976年观测得到的类星体 3C 286在 18 cm波段上的 VLBI数据重新作了处理.由此得到的图像要大大好于最初的处理结果,也获得了更多的有用信息.用几个Gauss模型去拟合校正后的UV数据,发现中央亮区可以被分解为两个致密结构,这与后来的高分辨率观测相一致.与不同历元的VLBI观测结果相比较,发现这两个致密结构间的距离不但在同一时间随观测频率变化,而且很有可能在同一观测频率上随时间变化. 相似文献
186.
D. Raimann E. Bica T. Storchi-Bergmann J. Melnick H. Schmitt 《Monthly notices of the Royal Astronomical Society》2000,314(2):295-306
We study the stellar population of galaxies with active star formation, determining ages of the stellar components by means of spectral population synthesis of their absorption spectra. The data consist of optical spectra of 185 nearby ( z 0.075) emission-line galaxies . They are mostly H ii galaxies, but we also include some starbursts and Seyfert 2s, for comparison purposes. They were grouped into 19 high signal-to-noise ratio template spectra, according to their continuum distribution, absorption- and emission-line characteristics. The templates were then synthesized with a star cluster spectral base.
The synthesis results indicate that H ii galaxies are typically age-composite stellar systems, presenting important contributions from generations up to as old as 500 Myr. We detect a significant contribution of populations with ages older than 1 Gyr in two groups of H ii galaxies. The age distributions of stellar populations among starbursts can vary considerably despite similarities in the emission-line spectra. In the case of Seyfert 2 groups we obtain important contributions from the old population, consistent with a bulge.
From the diversity of star formation histories, we conclude that typical H ii galaxies in the local Universe are not systems presently forming their first stellar generation. 相似文献
The synthesis results indicate that H ii galaxies are typically age-composite stellar systems, presenting important contributions from generations up to as old as 500 Myr. We detect a significant contribution of populations with ages older than 1 Gyr in two groups of H ii galaxies. The age distributions of stellar populations among starbursts can vary considerably despite similarities in the emission-line spectra. In the case of Seyfert 2 groups we obtain important contributions from the old population, consistent with a bulge.
From the diversity of star formation histories, we conclude that typical H ii galaxies in the local Universe are not systems presently forming their first stellar generation. 相似文献
187.
This paper develops a novel return mapping algorithm for the numerical integration of general isotropic finite strain elastoplastic constitutive models for geomaterials. The constitutive formulation is founded on multiplicative decomposition of the deformation gradient. The logarithmic strain measure as well as the exponential approximation of the plastic flow rule is utilized to restore the standard infinitesimal format return mapping algorithm. Central to the algorithm is the exploitation of a set of three mutually orthogonal unit base tensors for the representation of constitutive relations and the corresponding integration of the rate form of the constitutive equations. The base tensors constitute a local cylindrical coordinate system in the principal space, which allows to formulate the return mapping algorithm in the three‐dimensional space and reduce the dimension of the problem to be analyzed from six down to three. With the proposed approach, direct determination of the principal axes and the transformation procedure between the general space and the principal space, as required in traditional spectral decomposition, are avoided. Furthermore, the matrices that are involved in the inversion evaluation take simple forms, leading to extremely easy inverse computation. As a result, the consistent tangent operator can be streamlined into a form simpler and more compact than those by conventional integration methods. Following the formulation of the integration procedure, a numerical experiment is performed to assess the accuracy and efficiency of the proposed algorithm. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
188.
在新冠疫情的冲击下,国际关系错综复杂、瞬息万变,不稳定性不确定性剧增。全面及时地分析“全球-中国”国际关系变化特征,对于中国的外交发展规划具有重要的参考价值。复杂的国际关系可以分解为一系列事件单元,新闻数据中蕴含了时间、地点、人物、事物等关键信息,是构建事件的最直接、最全面的信息来源。本文以GDELT(Global Database of Events, Language, and Tone)新闻事件数据库为数据源,基于“全球-中国”的视角,利用2020年1—5月全球疫情相关新闻数据,研究新冠疫情事件背景下的国际关系的变化。本文首先以事件数量、事件强度值和事件被提及数作为关键变量,提出了国际关系的分类表达和计算模型,解决了国际关系表达模糊和难以计算的问题。然后从时空可视化角度展示疫情下国际关系的变化特征,并结合疫情期间的国际重要事件,进一步分析引起国际关系变化的原因。研究表明,采用本文方法能精确掌握新冠疫情下“全球—中国”国际关系的发展程度,发现“全球-中国”国际关系的变化规律和变化原因,具有重要的应用价值。本文的研究可以为大数据时代的国际关系研究提供一个新的视角,同时也为新闻数据的分析提供参考。 相似文献
189.
以海南1∶10 000 DLG数据为例,描述了基于ArcGIS制图表达机制、制图数据与GIS数据通过模板方式生产实现一体化存储的工作方法,为海南1∶10 000 DLG数据更新提供参考,能够实现地理信息获取实时化、处理自动化、传输网络化和服务社会化。 相似文献
190.