Modular and Versatile Spatial Functionalization of Tissue Engineering Scaffolds through Fiber‐Initiated Controlled Radical Polymerization

Native tissues are typically heterogeneous and hierarchically organized, and generating scaffolds that can mimic these properties is critical for tissue engineering applications. By uniquely combining controlled radical polymerization (CRP), end‐functionalization of polymers, and advanced electrospinning techniques, a modular and versatile approach is introduced to generate scaffolds with spatially organized functionality. Poly‐ε‐caprolactone is end functionalized with either a polymerization‐initiating group or a cell‐binding peptide motif cyclic Arg‐Gly‐Asp‐Ser (cRGDS), and are each sequentially electrospun to produce zonally discrete bilayers within a continuous fiber scaffold. The polymerization‐initiating group is then used to graft an antifouling polymer bottlebrush based on poly(ethylene glycol) from the fiber surface using CRP exclusively within one bilayer of the scaffold. The ability to include additional multifunctionality during CRP is showcased by integrating a biotinylated monomer unit into the polymerization step allowing postmodification of the scaffold with streptavidin‐coupled moieties. These combined processing techniques result in an effective bilayered and dual‐functionality scaffold with a cell‐adhesive surface and an opposing antifouling non‐cell‐adhesive surface in zonally specific regions across the thickness of the scaffold, demonstrated through fluorescent labelling and cell adhesion studies. This modular and versatile approach combines strategies to produce scaffolds with tailorable properties for many applications in tissue engineering and regenerative medicine.     

Generative methods in urban design: a progress assessment

The year 2007 marked the 20‐year anniversary of A New Theory of Urban Design (1987), a slender volume by Christopher Alexander and colleagues that serves as a notable milepost within the half‐century old “design methods movement” in which Alexander himself played a seminal role. The “generative” design method of A New Theory focused less upon the specification of a final form through schematic planning, and more on the stepwise process by which a form might emerge from the evolutionary actions of a group of collaborators. In so doing, it challenged the notion of “design” as a progressive expression of schematic intentions, and argued for a conception of design as a stepwise, non‐linear evolution in response to a series of contextual urban factors. In the 20 years since, significant progress has been made to develop the insights of generativity in urban design, as in other fields. Some of Alexander’s ideas have been incorporated – notably by practitioners of The New Urbanism – and some have been challenged and dismissed, including, notably, by Alexander himself. The author assesses progress since this milepost volume – substantial, he argues – as well as setbacks and shortcomings, and significant opportunities still remaining.     

考虑随机风压场非高斯特性的大跨度膜屋盖风振响应

作用于大跨度膜屋盖结构上的随机风压场在统计意义上由高斯和非高斯区域构成。基于零记忆非线性转化法理论,提出了这种混合随机风压场的模拟方法,算例表明,生成的随机风压场样本能准确描述实验数据的各项统计特性。将生成的样本和利用传统方法生成的高斯随机风压样本作用于某膜屋盖结构,经风振时域分析后发现,高斯随机风压激励下结构部分构件的响应值比非高斯随机风压激励下的响应值低,这表明,随机风压荷载的非高斯特性不容忽视。文章还给出了结构不同构件的整体风振响应系数。     

Kernel regression for real-time building energy analysis

This study proposes a new technique for real-time building energy modelling and event detection using kernel regression. We show that this technique can exceed the performance of conventional neural network algorithms, and do so by a large margin when the available training dataset is small. Furthermore, unlike the synapse weights in a neural network, the parameters of our kernel regression models are amenable to human interpretation and can give useful information about the building being studied. We extensively test our proposed algorithms using a new dataset consisting of 1.5 years of power and environmental measurements for four buildings, in addition to benchmarking against the ASHRAE Predictor Shootout dataset. On the new dataset, our kernel regression algorithm gave the best prediction performance in three of four cases and significantly outperformed neural networks (the nearest competitor) with training sets of 1/2 a year or less.     

宜兴大酒店装修改造“设计施工一体化”应用与研究分析

本文以宜兴大酒店装修改造为例,探析了＂设计施工一体化＂如何让酒店改造重新装修旧貌换新颜,如何把原来中规中矩、缺少格局变化的旧商务大楼规划成为配套设施完善,环境宜人的宾馆区。这对设计者来说是很大的挑战,也是十分值得探索的课题。     

建筑外墙体保温技术及质量控制研究

建筑的外墙体保温技术作为新世纪建筑水平的新标志,不仅关系到建筑工艺的发展问题,同时也与节约能耗、增加住房使用面积等民生问题息息相关。本文就对建筑外墙体的保温技术问题及质量控制方面给出了一些建议和看法。     

冷水机组的防冻技术研究

分别从水侧和制冷剂侧分析了冷水机组的防冻方法和原理,水侧防冻主要是从水流量和水温方面进行控制,制冷剂侧防冻主要是控制蒸发器内的制冷剂压力,从安装、维护和成本进行比较,冷水机组的防冻更倾向于从水侧防冻。从水侧进行防冻时,不同的蒸发器根据其特点采用不同的方法,干式蒸发器可仅从水温进行防冻;满液式和板式蒸发器需从水流量和水温两方面进行防冻保护,同时,板式蒸发器还需在进水管增加水过滤器;多个蒸发器并联时,可在每个蒸发器增加水流量和水温检测,也可在最不利环路采用流量开关和温度控制器并在总出水管增加流量开关的方法进行防冻。     

A classification control strategy for energy storage system in microgrid

Storage devices are indispensable elements in a microgrid to compensate for the power imbalance between loads and the distributed generator (DG) output. Different storage strategies give diverse performances in adjustment speed and capacity. Based on the performance of different storage devices and the features of power imbalance curve in different periods, a classification control strategy is proposed in this paper. First, storage devices are given priorities according to the adjusting speed, and the power imbalance curve is divided into two periods according to the changing speed. During an emergency, all the storages are employed to compensate the rapidly increasing power imbalance; during the steady period, storage device with higher priority is employed to track the instantaneous component of power imbalance, while storage device with lower priority is used to replace the kWh output of higher priority storage. The proposed strategy is tested in a microgrid within the subdistribution network of IEEE RBTS Bus6 system using Monte Carlo methods. Simulation results indicate that the classification control strategy could endow the system with fast adjusting ability through coordination between storages. Reliability indices of the testing system are utilized to demonstrate that the classification control strategy could improve the stability of the microgrid and reliability of the distribution network. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Institutionalizing infrastructure: photo-elicitation of cultural-cognitive knowledge of development

Infrastructure that goes unused – for example, after constructing the first water, electricity, sewers or road infrastructure in an infrastructure-poor community – is a common issue in new infrastructure development in the global south. In this case, while infrastructure has diffused, it has not become institutionalized. To better understand this problem, photo-elicitation methods are used to explore cultural-cognitive frames used by research respondents as they create and explain photograph symbols that represent change in their built environment. For example, respondents advocate for infrastructure they have reason to believe outsiders will provide as they evaluate the infrastructure against local utility in an early phase of institutionalization. Respondents also frame the research undertaking as an opportunity to actively diffuse infrastructure practices they have recently adopted themselves. By making these and other frames explicit, the photo-elicitation method reveals the elusive cultural-cognitive pillar of institutionalization and also provides insight into sources of self-reporting bias. The method also has particular advantages for research dealing with disadvantaged respondents, reduces issues of free recall bias and increases the length and depth of research interviews. Given the relative novelty of this method in construction research, its theory, advantages and limitations are discussed in some depth.