“八合一”理念下城市滨水空间营造的 六个维度

上海自2002年启动黄浦江两岸综合开发后,于2014年底提出《黄浦江两岸地区公共空间建设三年行动计划》,作为其中杨浦滨江南段公共空间的总设计师团队,深度介入了上海城市滨水空间的复兴。依托实践提出“八合一”理念,即城市设计、建筑设计、景观设计、市政设计、水工设计、生态修复、智能设计和艺术设计协同合作;并在突破学科壁垒的基础之上,构建包含系统化空间营造、历史文脉延续、基础设施复合、场景节点构筑、生态环境修复和公共艺术植入的六维城市滨水空间再生体系。     

权力变迁与村落结构的演化——以静升村为例

社会权力在村落中的运作需要通过具体建筑来承载,此类建筑也就成为控制村落结构的节点所在。在不同的历史时期,权力内容及其运作方式的改变将引起各个节点的变化,进而导致整个村落结构的变迁。本文以静升村为例,通过考察不同节点在不同时期的意义和用途等,探讨了权力的物化过程与村落结构的互动关系。     

A nested online scheduling and nonlinear model predictive control framework for multi-product continuous systems

In the pursuit of integrated scheduling and control frameworks for chemical processes, it is important to develop accurate integrated models and computational strategies such that optimal decisions can be made in a dynamic environment. In this study, a recently developed switched system formulation that integrates scheduling and control decisions is extended to closed-loop operation embedded with nonlinear model predictive control (NMPC). The resulting framework is a nested online scheduling and control loop that allows to obtain fast and accurate solutions as no model reduction is needed and no integer variables are involved in the formulations. In the outer loop, the integrated model is solved to calculate an optimal product switching sequence such that the process economics is optimized, whereas in the inner loop, an NMPC implements the scheduling decisions. The proposed scheme was tested on two multi-product continuous systems. Unexpected large disturbances and rush orders were handled effectively.     

Surrogate-based optimization of a periodic rescheduling algorithm

Periodic rescheduling is an iterative method for real-time decision-making on industrial process operations. The design of such methods involves high-level when-to-schedule and how-to-schedule decisions, the optimal choices of which depend on the operating environment. The evaluation of the choices typically requires computationally costly simulation of the process, which—if not sufficiently efficient—may result in a failure to deploy the system in practice. We propose the continuous control parameter choices, such as the re-optimization frequency and horizon length, to be determined using surrogate-based optimization. We demonstrate the method on real-time rebalancing of a bike sharing system. Our results on three test cases indicate that the method is useful in reducing the computational cost of optimizing an online algorithm in comparison to the full factorial sampling.     

A ternary mechanism for the facilitated transfer of metal ions onto metal–organic frameworks: implications for the ‘‘versatility’’ of these materials as solid sorbents

Although metal–organic frameworks offer a new platform for developing versatile sorption materials, yet coordinating the functionality, structure and component of these materials remains a great challenge. It depends on a comprehensive knowledge of a “real sorption mechanism”. Herein, a ternary mechanism for U(VI) uptake in metal–organic frameworks was reported. Analogous MIL-100s (Al, Fe, Cr) were prepared and studied for their ability to sequestrate U(VI) from aqueous solutions. As a result, MIL-100(Al) performed the best among the tested materials, and MIL-100(Cr) performed the worst. The nuclear magnetic resonance technique combined with energy-dispersive X-ray spectroscopy and zeta potential measurement reveal that U(VI) uptake in the three metal–organic frameworks involves different mechanisms. Specifically, hydrated uranyl ions form outer-sphere complexes in the surface of MIL-100s (Al, Fe) by exchanging with hydrogen ions of terminal hydroxyl groups (Al-OH₂, Fe-OH₂), and/or, hydrated uranyl ions are bound directly to Al(III) center in MIL-100(Al) through a strong inner-sphere coordination. For MIL-100(Cr), however, the U(VI) uptake is attributed to electrostatic attraction. Besides, the sorption mechanism is also pH and ionic strength dependent. The present study suggests that changing metal center of metal–organic frameworks and sorption conditions alters sorption mechanism, which helps to construct effective metal–organic frameworks-based sorbents for water purification.     

Comparative study on overall and local static performance of steel open-web girders

To quantify the mechanical properties of five types of steel open-web girders that have been tested or applied in practical engineering, a systematic study of the overall and local mechanical properties of steel open-web girders based on the same dimensions and material conditions was presented. An overall study of the quasi-intersection beam method for shear deformation was introduced for 8 × 8 grid open-web girders to derive the determinants of the load distribution factor. Based on the load distribution factors, the essence and formula of any shear key node domain (SKND) were derived theoretically. The reliability of the numerical model was verified by tests on the H-type unidirectional SKNDs, which led to a comparative load–displacement study of unidirectional and bidirectional SKNDs. Quantitative results of the overall flexural capacity and SKND load capacity of the H-type, TH-type, TS-type, T-type, and DT-type open-web girders were obtained. The maximum shear deformation in the elastic phase of the five open-web girders accounted for 39.04% to 54.76% of the overall deformation. In this study, the adjustment factors of the modeling analysis based on the current practical design of equivalent dense-ribbed solid beams (DRSBs) were revised. A method of SKND's design load capacity under the action of bidirectional forces was put forward for the first time.     

基于变采样周期的CPS多重优先级调度研究

信息物理融合系统(CPS)是实现能源互联网中信息技术和电网技术融合的重要技术体系。针对在CPS中采用传统调度策略导致的高丢包率、低利用率和网络延时长等问题,提出了一种多重优先级的调度策略,该调度策略能够保证信息在网络中传递的灵活性;基于该调度策略,针对CPS不同组成部分的特点,提出了两种变采样周期算法,该算法能够同时兼顾网络资源情况和系统控制性能,使系统在网络资源受限的情况下能够达到稳定状态。最后,根据能源互联网的特点,描述了如何将该调度策略应用于能源互联网中。     

考虑电网关联度的电力通信网关键环节识别

电力通信网作为电网的支撑网络,其可靠运行对电网安全可靠运行有着重要意义。为了识别电力通信网的关键环节,提出了一种考虑电网关联度的电力通信网关键环节识别方法。首先,构建电力-通信复合系统,其次,分别构建电力系统层节点评价体系、链路评价体系和通信系统层节点评价体系、链路评价体系,然后采用TOPSIS算法分别求得电力系统层节点重要度、链路重要度以及通信系统层节点重要度、链路重要度。最后,通过特定的代数运算,将电网关联度与通信网自身的重要度结合起来,分别求得考虑电网关联度的电力通信网节点、链路重要度值,并依据重要度值,识别出电力通信网关键环节。某省实际电力通信网仿真结果表明,该方法可以有效地识别出关键环节,证明了该方法的可行性。     

三相不平衡低压微网的多目标优化调度

提出了一种含多种分布式电源的三相不平衡微网综合优化调度策略。首先,确定了三相不平衡微网安全、经济、高效运行的评价指标;建立了多目标优化调度模型,并通过对多目标调度模型的求解得到微网的运行策略。其次,对各目标函数从不同的运行角度进行了分析,以充分利用多目标方法的有效性。算例仿真验证了所提出的优化调度策略在充分发挥各种分布式电源作用方面的优势。     

电动汽车充电站在配电系统中电气接入点的最优选择

针对电动汽车(electric vehicle,EV)充电负荷在空间中的合理布局等问题,现有相关文献主要围绕充电站的选址和定容展开研究,尚未论及如何确定充电站在所属区域配电系统中的电气接入点。在此背景下,该文针对计及对潮流影响的电动汽车充电站电气接入点的选择问题进行探讨。首先,依据电动汽车出行统计数据拟合结果,获得初始荷电状态(state of charge,SOC)及起始充电时刻分布特性,建立电动汽车充电负荷的概率模型,同时利用蒙特卡洛仿真求解,并采用深圳市电动出租车的实际数据对这种方法做了验证。之后,以节点电压偏差百分数和支路有功功率损耗增量百分数为基础,构造了评价充电站对配电系统潮流影响的综合指标,进而提出了确定充电站最优电气接入点的方法。最后,以修改的IEEE 33节点配电系统为例对所提出的方法进行了说明。