The influence of node sequence and extraneous load induced by graphical overviews on hypertext learning

The effects of four hypertext learning environments with a hierarchical graphical overview were studied on the coherence of the node sequence, extraneous load and comprehension. Navigation patterns were influenced by the type of overview provided (i.e., dynamic, static) and whether navigation was restricted (i.e., restricted, non-restricted). It was hypothesised that redundant use of the overview for inducing a high-coherence reading sequence would result in high extraneous load and low comprehension. Coherence was higher in the dynamic than in the static conditions. Coherence was also higher in the restricted than in the non-restricted conditions. Mental effort as a measure of extraneous load was higher at the end than at the beginning of the learning phase, especially in the dynamic restricted and the static non-restricted conditions, although there was no significant interaction. Comprehension was lowest in the dynamic restricted condition and highest in the dynamic non-restricted and static restricted conditions. Low comprehension in the dynamic restricted condition indicates that overviews can become redundant for reading sequence coherence, negatively impacting comprehension. The evidence suggests that severe restriction of navigation paths should be avoided and that continuous use of overviews such as in dynamic overviews may be detrimental to learning.     

Experimental Study on Shear Localisation in Granular Materials Within Combined Strain and Stress Field

Abstract: The characteristic features of the shear zones formation in deforming granular materials were investigated using particle image velocimetry (PIV), which was combined with a photo‐elastic study of the stress field. Laboratory tests were performed for an active translation of rigid retaining wall. PIV is an optical technique for measuring displacement fields from successive digital images and was employed to analyse experiments on two different granular materials, composed of (1) sand grains and (2) glass granules. The tests on glass granules were supplemented by taking photo‐elastic images in circularly polarised light to gather information on changes in the average stress field, accompanying the specimen deformation. Attention was focused on the effect of the initial density, grain coarseness and magnitude of wall displacement on shear localisation within a strain field and its geometrical relation to some structures found in the stress field.     

基于Node.js技术的报表信息管理平台设计与实现

文章利用Node.js框架进行报表信息管理平台的开发,实现对不同类型报表信息的填写、查询、导出等操作。系统前端采用Vue-cli构建前端工程项目,Element组件设计页面;后端采用Java语言,数据库采用MySQL数据库。利用其高效、实时响应的特点,提高办公效率。     

接口技术在数据库中的应用

接口技术在数据库中得到了广泛的应用,认识和掌握访问数据库的接口技术和方法以及性能的好坏,对于开发者至关重要。本文以Visual Basic为开发平台,介绍了接口技术在数据库中的应用。     

用于先进的双嵌入和栓工艺的低缺陷钨CMP高性价比浆料(英文)

介绍了用于钨双嵌入和钨栓CMP工艺的新型CMP3200TM氧化铝浆料,测试证明,这种浆料在110nm技术节点的钨CMP工艺应用中取得了理想的效果。通过对氧化铝粒子制造工艺的有效控制,获得了可满足110nm技术节点双嵌入和栓层钨CMP工艺要求的低缺陷率,高性价比的氧化铝蛐硝酸铁浆料。从而在价格竞争激烈的半导体制造领域,特别是代工市场引起了业界越来越多的关注。     

Strain Measures for Rigid Crushable Foam in Uniaxial Compression

Abstract:  Progressive collapse deformation mechanisms in Rohacell-51WF foam during uniaxial compression has been studied. Measures of a macroscopic engineering strain are identified. The elastic and plastic parts of a macroscopic engineering strain can be predicted by using the compression failure strain, lock-up strain, and time dependent elastic and plastic parts of lock-up strain, which are material parameters. Identification of strain measures in a uniaxial compression test is essential to get material parameters for an elastoplastic model. The viscoelastic recovery property of Rohacell-51WF foam is also described.     

城市网络研究：由等级到网络

本文从城市等级到城市网络转化的研究视角,在文献回顾的基础上,对城市网络研究的转变模式、网络结构特征、单个城市与城市网络的关系等方面进行了探讨。研究认为：（1）从城市单体来看,可从城市等级的中心性与城市网络的节点性组成四象限分析城市的特性并对城市进行归类;（2）从城市联系通道来看,城市等级到城市网络经过了单向与非对称、通道少到双向、通道多样化的转变,作者从联系方向、联系主体、联系大小、联系空间、联系途径等方面进行了对比研究;（3）从城市外部联系角度来看,可从点、线、网络结构方面进行城市网络的分析研究;（4）结合城市网络特征,单个城市与城市网络的基本关系可从节点、关系通道、联系强弱、聚类特征、抗风险性等方面进行分析。     

术前乳腺B超及MRI检查对乳腺癌患者腋窝淋巴结状态评估的准确性评估

目的:对术前乳腺B超及MRI检查对乳腺癌患者腋窝淋巴结状态评估中的临床价值进行评价分析,为今后的临床诊治工作提供可靠的参考依据。方法:抽取在2010年8月-2013年8月间我院收治的乳腺癌临床患者136例,对其在根治术前行乳腺B超及MRI检查,并以术后病理结果为依据,对乳腺B超及MRI检查在腋窝淋巴结状态评估中的准确性进行评估,并展开对比分析。结果:经比较发现,乳腺B超与MRI检查对腋窝淋巴结状态评估准确性无明显差异(P0.05),二者联合后准确性较单独使用时发生显著升高(P0.05)。结论:在乳腺癌腋窝淋巴结状态评估中乳腺B超、MRI检查的临床准确性无明显差异,联合使用后可有效提高检测准确性,值得关注。     

A hierarchical Path Computation Element (PCE)-based k-random-paths routing algorithm in multi-domain WDM networks

We propose an inter-domain routing algorithm for multi-domain wavelength-division multiplexing (WDM) mesh networks. On the basis of the hierarchical Path Computation Element (PCE) architecture, the proposed algorithm introduces a k random path strategy in the parent PCE to adjust the algorithm optimization level. Simulation results indicate that the proposed algorithm outperforms previous schemes in terms of blocking probability and resource utilization, while preventing the increase in PCEP signaling overhead.     

钢管混凝土新型筒仓柱节点设计与有限元分析

结合筒仓结构的特点,设计一种新型的钢管混凝土节点型式,对节点的传力机理和力学性能进行分析,并提出了新型节点的初步设计（计算）方法,为工程设计人员在实际应用中提供思路和参考。并采用通用有限元软件ANSYS对节点进行非线性有限元分析,验证所建议节点的承载力。