新时期我国都市圈治理的新逻辑与变革方向探讨

20世纪末以来,我国多地开始了都市圈治理的探索实践,随着国家提出培育发展现代化都市圈,都市圈正式成为国家治理体系中重要的调控单元。作为城镇化战略、区域发展战略和乡村振兴战略叠加的重要地域空间,新时期都市圈的治理创新是一项重要的实践课题。文章回顾了过去我国都市圈治理的主要做法与瓶颈制约,借鉴国际都市圈治理的典型经验,探讨我国都市圈治理的新逻辑和新方向,提出新时期都市圈治理应遵循“平等协商、同城发展、互利共赢”的逻辑,创新规划理念与方法,建立全方位协调机制;国家应以同城化发展为目标,积极推动相关立法工作和统计制度改革,开展都市圈发展综合试点研究与实践。     

阿尔瓦·阿尔托人情化创作之解读

阿尔瓦·阿尔托是一位极有特色的建筑师,他的人情化理论及实践作品深深地影响了一代人。本文从他对本能的认识、对方言原型的借鉴、对空间的理解以及对自然的模仿这四个方面,对他的人情化创作进行探讨,希望对现今的人性化建筑设计有一定的启示作用。     

SMW工法的应用研究

根据工程实例 ,说明了采用SMW工法 ,形成挡土和隔水的复合结构 ,能够确保基坑的安全 ;从施工过程、施工中的注意事项等方面阐述了SMW工法的应用     

临时性到常备化:突发公共卫生事件下救治设施空间规划供给研究

新型冠状病毒肺炎疫情对人类健康安全、经济发展和社会稳定造成了巨大的威胁。为应对疫情,我国很多城市建设了临时性的应急救治设施。文章从广西龙潭医院临时全负压病区建设面临的问题出发,分析了空间规划供给不足导致城市在应对突发公共卫生事件中的被动性,认为临时应急救治设施应当向常备化转变。从空间规划内容的角度,提出将突发公共卫生事件的救治设施分为永久专用救治设施、临时专用救治设施和临时借用救治设施3类,实现多元设施的复合式常备化供给;要以区域观来构建不同层级的区域防疫救治设施联动体系;提出要将突发公共卫生事件救治设施纳入空间规划体系,并在省级、市级、县级国土空间规划、控制性详细规划中进行有效传导与落实。     

基于专家知识与BP神经网络的架空导地线状态评价研究

目前输电设备运维过程存在着规程过于繁杂,规定的参量较为冗余等问题。提出了一种导地线状态评价方法,该方法通过关联分析从规程中提取出日常运维过程中广泛应用的关键参数作为运行状态的评价指标,并采用灰色关联确定对设备运行状态具有强关联性的外界因素作为影响因子,结合运维专家经验建立导地线状态评价专家系统,提高状态评价的准确性与可靠性。采用历史缺陷样本与专家系统评价样本作为训练样本,通过Levenberg-Marquardt算法进行BP神经网络的训练,建立融入专家经验的导地线智能状态评价模型。通过运行实例分析表明本文训练得到的状态评价模型能够准确地实现对导地线的状态评价,具有相当可靠性。     

传动销齿故障时间分布定量化建模及应用

为确保飞机调向转盘装置执行调运任务的成功率,对其关键部件传动销齿的故障时间分布规律进行研究.采用基于极大似然估计和相关系数拟合优度检验建立可靠的传动销齿故障时间分布函数,并应用于飞机调向转盘装置的使用和维护,最后进行实例分析.分析结果表明:建立的传动销齿故障时间分布函数对飞机调向转盘装置的使用和维护具有一定的指导意义,能够确保飞机调向转盘装置执行调运任务的成功率.     

环境·意境·心境——基于城市意象理论的风景名胜区规划方法

近年来,风景名胜区的特色流失和风貌趋同现象越发明显,急需探索一套能够增强风景名胜区特色的规划方法。文章通过对城市意象理论的深入研究和风景名胜区规划实践的系统分析,将城市意象理论引入风景名胜区规划,提出了道路等级化与景观化、边界层级化与刚性化、区域空间联动一体化、节点人性化与场域化、标志物特色化与符号化等规划策略,并结合广西壮族自治区灵山县六峰山—三海岩风景名胜区总体规划进行分析,以期为其他风景名胜区规划提供借鉴。     

Seismic Data‐Driven Identification of Linear Models for Building Structures Using Performance and Stabilizing Objectives

A two‐stage dual‐objective structural identification method is presented in this article. The complexity of the identification of story‐level physical models for large‐scale building structures is first addressed through a comparative study. A stiffness variation‐based stabilizing objective is proposed to be necessarily incorporated into iterative optimization with the classical performance objectives to improve the model feasibility, and an area‐type evaluation index is subsequently proposed for the stopping criteria. Accordingly, a two‐stage differential evolution‐based dual‐objective optimization framework is presented for the computation of Pareto fronts for nondominated candidate solutions. Then, the proposed method is investigated using two illustrative examples, including a nine‐story benchmark structure, and a real‐world seven‐story reinforced concrete structure. A series of condensed models are identified from the nondominated solutions on the Pareto front. The prediction performance of the single‐objective optimal model and the dual‐objective acceptable models is compared using the overall discrepancies of acceleration, interstory drift, and modal properties, within both estimation and validation cases. Incorporation of the noise effect into the method is finally studied and discussed.     

Optimizing Location and Capacity for Multiple Types of Locomotive Maintenance Shops

Thousands of locomotives run in the North America railroad network and each of them must receive periodic maintenance service; meanwhile, the locomotives may break down during shipment operations and demand repair. Maintenance shops are characterized by the types of locomotives they can handle and the level of service they can provide. This article formulates a mixed‐integer program model to optimize location and capacity of locomotive maintenance shops. The objective is to minimize the sum of the costs for building new (or shutting down existing) maintenance shops, the costs for capacity expansion (or reduction), and the costs for shipping broken locomotives to a suitable shop. A Lagrangian‐relaxation‐based heuristic algorithm is proposed to solve the shop location and capacity planning problem. The model and solution techniques are applied to a full‐scale real‐world case study, while the computational results show that the current maintenance shops are overly built and recommend that two maintenance shops should be closed and an amount of capacities should be reduced from the existing shops. A series of numerical sensitivity analyses are also conducted to draw managerial insights.     

无底柱分段崩落法斜壁边界条件放矿实验

为了研究无底柱分段崩落法斜壁边界条件下矿石散体的移动规律,开展了斜壁边界条件下的底部放矿实验。按照1∶25的几何相似比,制作了无底柱分段崩落法斜壁边界条件下底部放矿模型,根据矿山现场矿石块度级配,制备了对应级配的矿石散体材料及流动性与散体材料一致的标志颗粒。在实验数据的基础上,绘制了各水平层标志颗粒放出量曲线图,分析了矿体厚度和上下盘边壁对散体流动规律的影响。结果表明,矿体厚度对散体流动规律影响较小,在上下盘边壁的约束作用下,同一水平层,越靠近上盘的散体越先被放出。结果对无底柱分段崩落法放矿工艺的研究和应用具有一定指导意义。