城市增长边界的性质及划定方法探讨——杭州市生态带保护与控制规划实践

随着我国城市化进程加速推进,城市增长与土地资源和生态环境保护等矛盾已日益凸显。划定城市增长边界(UGB)是协调建设与生态保护的有效手段。结合杭州生态带规划案例,对城市增长边界的性质进行辨析,提出刚性UGB与弹性UGB的区别。运用生态敏感性分析、景观生态安全格局构建和建设用地规划等方法,以及面对建设与保护冲突的规划决策方法,探讨了UGB的划定方法,并指出UGB在我国规划应用中需要进一步完善的方面。     

同源高速宏观地质条件对勘察的指导意义

对同源高速公路地貌景观进行了分析,并针对不同地质条件下的工程地质特征进行了工作量布置前的探讨,综合研究后进行了勘察工作,合理指导了勘察与工程建设,对同类工程具有重要的指导意义。     

Modes of making smart cities: Or,practices of variegated smart urbanism

The ‘actually existing’ smart city is not a monolith. It is not directed by a universal logic, nor does it develop in a standardised way. As recent research has argued, the spatial, material, and political contexts of cities have major influence over what smart urbanism looks like in practice. This paper adds analytical depth to, and broadens the geographical scope of, research on the variegated modes of making smart cities. Based on empirical research in multiple Australian cities we use three case studies to explore three different modes of smart urbanism, each one centred on the interests of a different key actor: corporate-centric, citizen-centric, and planner-centric. These different modes can, and do, co-exist in the same city. At times, they are competing logics that fight to pull the city in different directions. Yet, they can also work together to shape smart city initiatives. In describing these different modes, we pay particular attention to the ways that these projects and strategies must contend with the already existing spatial, cultural, and political contexts of each place.     

Phase Equilibria of BaO-R2O3-CuO z Systems (R = Y and Lanthanides) under CO2-free Conditions

For applications ranging from phase equilibria to the processing of second-generation high T _c superconductor-coated-conductors, phase diagrams constructed under carbonate-free conditions are needed. Subsolidus phase equilibria of BaO-R₂O₃-CuO _z (R = Ho) have been investigated at (810°C), 21 kPa (875°C) and 0.1 MPa (850 and 930°C) by applying controlled atmosphere methods to minimize the presence of carbonate and CO₂ and H₂O contamination. Under carbonate-free conditions, most of these phase diagrams are different from those reported in the literature. In this paper, we also review and compare the phase diagrams of ten BaO-R₂O₃-CuO _z systems (R = Nd, Sm, Eu, Gd, Dy, Y, Ho, Er, Tm and Yb) that were previously determined in this laboratory under Among these diagrams, a distinct trend of phase formation and tie-line relationships is observed.     

工艺条件对PTCR热敏陶瓷喷雾造粒粉体性能的影响

采用压力喷雾造粒的方式对BaTiO3系PTCR热敏陶瓷粉体进行喷雾造粒处理,研究了喷雾造粒过程中浆料组成和雾化条件对粉体性能的影响。研究结果表明：喷雾造粒过程中浆料粘度过高,雾化条件控制不当,都会使喷雾造粒粉体颗粒的团聚程度增加,影响粉体的松装密度和流动性,对生坯成型及材料烧结不利,考虑到料浆中粘合剂含量、固体物含量的综合影响,添加适量的分散剂可以降低料浆的粘度,控制适当的雾化压力,选用合适的喷雾直径与涡旋片组合可以获得理想的粉体。     

最小生成树算法在城市基础建设中的应用

随着城市基础建设规模的逐步扩大,所需建设资金也大幅提高,只有对各类系统进一步优化才能提高其运行的经济效益和利用率,降低其成本。本文采用最小生成树算法对城市基础建设布局进行设计,重点以暖气供应为例进行阐述。     

光纤光阱力计算的近似条件及误差分析

光纤光镊技术利用光纤出射的光束捕获和操控粒子,其飞速发展对光阱力的理论研究提出了更高的要求。采用射线光学模型对光纤光阱中的米氏微球所受到的光阱力进行数值模拟,讨论了光阱力计算中可采用的近似条件及其应用范围,比较了在近似条件下与直接计算情况下结果的差异,分析了微球与光纤端面之间的距离对近似计算的影响。理论分析和模拟计算表明,当微球与光纤端面之间的距离大于临界值时,可对计算模型中光束在微球表面的入射角、入射点的方位角等角度参量作近似处理,该结论为简化光纤光阱力计算提供了理论依据。     

彩色多频同步显示器行激励级电路的倒推设计法（1）

行激励级电路的设计是完全为行输出级服务的,它实质上是行输出级电路设计的一个重要而不可分割的组成部分。因此行激励级电路的设计,自然采用了从显象管偏转线圈和行输出管到激励变压器和行激励级的倒推设计法。     

基于时空感知的用户角色推理

随着大数据和信息技术的发展,更好地理解用户的行为轨迹在个性化推荐、广告推荐等方面越来越重要。该文依据大数据环境下的城市计算理论,提出一种基于情境感知的用户角色推理模型。通过用户的行为轨迹分析其行为的时空特性;结合时间、语义分析等构造识别用户角色概率推理模型;通过算法克服识别用户角色的主观性、动态适应性差等问题。实验结果证明了该文所提模型的可行性、精确性和预测准确性。     

Global maximum power point tracking based on new extremum seeking control scheme

A new perturbed‐based extremum seeking control (PESC) scheme is proposed in this paper to track the global maximum power point (GMPP). The PESC scheme has two control loops based on power of the photovoltaic (PV) array: the first loop operates as usually to track the maximum power point and the second sweeps all local MPPs to locate the GMPP. Once the GMPP is located based on its uniqueness (after the PV pattern is quickly scanned many times, depending on the PV pattern's profile), the GMPP is accurately tracked based on first control loop. The used PV patterns have the profile of the PV power characteristics obtained for PV array under partially shaded conditions (PSCs). This PESC scheme is proposed to track the GMPP in the PV applications, but also in other multimodal problems from industry, being a good motif to revive the specialists' interest for the extremum seeking control field. The results obtained here are very promising for both search speed and tracking accuracy performances of the GMPP under different PSCs simulated on the PV array. Thus, the energy efficiency of PV array controlled with the proposed PESC scheme will increase with more than 1.2% in comparison with that obtained with the other MPP algorithms because of better performance shown by this PESC scheme. A 99.6% tracking accuracy is obtained here in comparison with a maximum 98.4% tracking accuracy reported in the literature. Furthermore, 100% hit and high search speed are obtained here for the GMPP localization. Copyright © 2015 John Wiley & Sons, Ltd.