中国城市空间结构绩效研究评析与展望

在我国当前快速城市化的进程中,城市空间结构绩效的优劣直接影响着城市的健康和可持续发展。文章通过回顾我国城市空间结构绩效的研究概况,对其内在机理、评价指标体系、良好绩效的空间结构形态以及提高城市空间结构绩效的措施等主要研究内容进行梳理和评析,并在此基础上展望未来的研究方向,以期有助于该领域在我国的研究获得新的突破。     

南山城小学

我们被这个优雅的方案打动了。We are delighted with the elegance of the design.尽管最初的设计始于1995-1996年,但是直到2001-2003年这个建筑才动工建设,是建筑面积6 200平方米的低预算建筑。场地位于靠近京都的南山城村,并处在村中主要街道上。学校坐落在一个山坡上,可以俯瞰乡村的全景。     

拉索式双曲面玻璃幕墙建造技术

随着建造工艺技术水平的提高,玻璃幕墙的形式以及连接方式也日新月异,以新疆国际会展中心工程独特的悬挑明月造型为例,其5层南北两侧设计为椭圆悬挑观景窗拉索式玻璃幕墙,工程采用特制的钢拉索点支以及玻璃自平衡方法进行固定,通过优化设计、实施成套施工技术,最终很好地表现了建筑造型的美观效果,为同类工程积累了一定的经验.     

基于GIS的大孤山露天矿边坡稳定性分析研究

针对辽宁省鞍山市大孤山露天铁矿北端边坡出现滑动变形这一现象,通过详细的地质调查和边坡节理裂缝的测定,利用TM30监测露天矿边坡的变形情况。用FLAC软件进行数值模拟分析边坡的稳定性。采用时间序列分析监测数据,并总结出边坡变形的一般性规律。建立起基于GIS的大孤山露天矿变形监测预警系统。     

Enhanced sound absorption properties of porous ceramics modified by graphene oxide films

Under the condition of constant thickness, improving the low-frequency sound absorption performance of conventional sound-absorbing materials is a challenging research topic. To address this issue, a new reduced graphene oxide/polyvinyl alcohol (RGO/PVA) porous composite ceramic was fabricated using freeze-drying and optimized by redesigning the internal connecting pores of porous ceramic matrixes with a reticular microstructure using RGO and PVA. The as-prepared porous structure showed significant enhancement in the low-frequency sound absorption band compared with pristine porous ceramics. In addition, the hybrid porous ceramics exhibited low thermal conductivity. These favorable properties indicate that the hybrid sound-absorbing ceramics have potential application prospects for noise reduction in the fields of construction and electrical and mechanical devices.     

Sharpening polycrystalline phase boundary for potassium sodium niobate ceramics with MnF2 modification

The influence of anion on structure and performance is unclear in potassium sodium niobate ((K,Na)NbO₃; KNN)-based ceramics, while cation doping has been widely researched. Here, the phase structure and electrical properties are explored in MnF₂-doped KNN ceramics. Significantly, sharp rhombohedral–orthorhombic (R–O) and orthorhombic–tetragonal (O–T) phase boundary as well as reduced diffusion degree is exhibited in the ceramics along with little changed phase transition temperatures due to the optimized F⁻ content at O site, which is different from that of cation replacement for A and B sites. Notably, the domain wall motion is facilitated due to the increased A vacancy and decreased O vacancy along with strengthened polarity, originating from the higher valence state and electronegativity of F⁻ with respect to O²⁻. And then, enhanced ferroelectricity is realized via MnF₂ modification, the piezoelectricity is elevated in turn. This work presents a new idea of anion doping for controlling structure and properties in perovskite materials.     

一种基于传感器数据综合处理算法

提出基于知识参量的数据标准化处理方法,介绍了知识参量的构成以及故障征兆的隶属度表示方法.根据功率相等的原则提出了传感器数据中的野值滤波方法.运用神经网络和最小二乘法加权的方法对缺损数据进行填充,并分别与最小二乘法和BP网络的处理结果进行比较.仿真结果表明,运用该方法进行数据处理,可以在保证数据完整准确的情况下,有效地弥补原始数据的缺陷,提高了数据的准确性和可信度.     

变频器技术及其在煤矿中的应用

文中详细阐述了变频器技术和功能特点，及该技术在煤矿生产中构成的实用电机控制系统，并评述了它的应用前景。指出，该技术在风机、泵类等的电机控制系统中，可获得显著的节能效果。     

混合溶剂芳脂比与特定温度下密度的关系

为提高生产效率、降低生产成本、快速判断混合溶剂芳脂比,研究了混合溶剂芳脂比与特定温度下密度的关系。实验结果表明,混合溶剂的芳脂比与其特定温度下的密度之间存在明显线性关系,且该线性关系对生产具有指导意义。     

无机阻燃剂研究进展

无机阻燃剂无毒或低毒,燃烧时能防流滴,不产生烟雾,很多还有抑制烟雾的作用,完全符合当今阻燃剂向环保型发展的大趋势。对无机阻燃剂的研究现状进行了综述,从而为其深入研究开发提供参考。