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11.
Stephen V. Ward 《Planning Perspectives》2013,28(2):295-313
A key feature of modern planning history has been the identification of cities admired for their ‘good planning’. In varying degrees, they have stimulated emulation, selective or partial borrowing, or even direct copying of their admired planning features. Model cities at different phases of planning history include Paris, Frankfurt, Vienna, Moscow, London, Stockholm, Barcelona, Chicago, New York, Portland and Vancouver. In recent years, new models have emerged, such as Singapore or Curitiba. The article considers how such cities became or are becoming models. It examines the methods by which the knowledge and reputation of the ‘model’ are promoted and disseminated. The importance of key actors, and visits, conferences and exhibitions focused on planning issues are considered. So too are less specific factors which help draw the gaze of a wider world. The article also considers whether such cities were/are places where new planning approaches have been invented or where they were implemented on a larger scale. Overall the paper discusses a key and strengthening feature in the circulation of contemporary planning knowledge. It does not answer all the surrounding questions in any definitive sense but opens up new debates about planning and the processes behind its historical evolution. 相似文献
12.
Developing toughened aromatic polybenzoxazines using thermoplastic oligomers and telechelics,part 1: Preparation and characterization of the functionalized oligomers 下载免费PDF全文
Ian Hamerton Lisa T. McNamara Brendan J. Howlin Paul A. Smith Paul Cross Steven Ward 《应用聚合物科学杂志》2014,131(19)
The preparation and characterization of three families of thermoplastic oligomers (Mn = 2918–13263 g mol?1) based on polyarylsulfone (PSU) differing in both molecular weight and terminal functionality and one series of polyarylethersulfone (PES) of different molecular weights is reported. Infrared and nuclear magnetic resonance spectroscopy data support the formation of both the hydroxyl terminated oligomers and conversion (67–89% depending on molecular weight) to the telechelic PSU oligomer bearing reactive benzoxazine groups. Differential scanning calorimetry reveals that the onset of homopolymerization in the telechelic PSU oligomer occurs at around 100°C (peak maximum 125°C at 10 K/min) and rescans show values of the glass transition (for the homopolymers) ranging from 124 to 167°C depending on molecular weight. The influence on the oligomer backbone and terminal functionality is examined using thermal analysis. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40875. 相似文献
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Despite their many benefits, microcomputers can dramatically increase the vulnerability of an organization's information system. As these devices are integrated in an organization, computer hardware, software, and data become widely dispersed, enabling more individuals to access information. Widespread use of microcomputers, especially when coupled with their ability to communicate with larger systems, requires early formulation and implementation of security and control procedures that differ substantially from those established in mainframe environments. 相似文献
15.
Adam J. Hall Michael J. Chappell John A.D. Aston Stephen A. Ward 《Computer methods and programs in biomedicine》2014
A four compartment mechanistic mathematical model is developed for the pharmacokinetics of the commonly used anti-malarial drug artesunate and its principle metabolite dihydroartemisinin following oral administration of artesunate. The model is structurally unidentifiable unless additional constraints are imposed. Combinations of mechanistically derived constraints are considered to assess their effects on structural identifiability and on model fits. Certain combinations of the constraints give rise to locally or globally identifiable model structures. 相似文献
16.
F. Schröder R. M. Ward A. R. Walpole R. P. Turner M. M. Attallah J.-C. Gebelin 《Materials Science & Technology》2015,31(3):372-384
Linear friction welding of the Ti6Al4V alloy is studied. A new definition of the energy input rate is proposed, based on an integration over time of the in-plane force and velocity; a strong correlation with the upset rate is then found. The effective friction coefficient is estimated to be 0·5±0·1 for varying frequencies and amplitudes, with only a weak dependence on the processing conditions displayed. A model is proposed that accounts for both the conditioning and equilibrium stages of the process, which is shown to be in good agreement with the experimental data. The model is used to study the mechanism by which the flash is formed. A criterion is proposed by which the rippled nature of its morphology can be predicted. 相似文献
17.
Information technology (IT) implementation continues to be a challenging process for many organizations. The challenge is heightened when systems are changed due to mergers and acquisitions (M&A). The recent focus on IT-service management highlights the importance of having positive relationships between IT-service providers and end-users. In an M&A situation, there is often little history, and thus limited basis for trust in the IT organization, yet systems often need to be changed in these situations. The current study examines the IT-service provider’s relationship with the end-user to ascertain the factors that influence that relationship and ultimately influence end-user attitudes toward the new system. We study a mandated implementation following an acquisition in the banking industry. The results highlight the important and fragile nature of trust in the IT-service provider. In addition, the results demonstrate that there are significant differences in what matters at what time during the implementation process. 相似文献
18.
Faith Bamiduro Michael B. Ward Richard Brydson Steven J. Milne 《Journal of the American Ceramic Society》2014,97(5):1619-1624
The crystallization of ZnO microrods by hydrothermal treatment of a suspension formed from reaction of zinc acetate and sodium hydroxide has been examined using scanning and transmission electron microscopy. Polycrystalline hexagonal ZnO microrods first appeared after 0.5 h reaction time at 120°C. These early stage rods were composed of stacks of hexagonal layers, each ~50 nm in thickness containing closely aligned assemblies of nanocrystallites <20 nm in size. Further growth of the microrods involved columns of nanoparticles extending from the basal layers of the preformed hexagonal stacks. Re‐crystallization produced single‐crystal microrods, many of which existed as twin particles. 相似文献
19.
Polymer gel electrolytes have been prepared using lithium tetrafluoroborate (LiBF4), propylene carbonate (PC) and polyvinylidene fluoride (PVDF) at 20% and 30% concentration by mass. Self diffusion coefficients have been measured using pulse field gradient nuclear magnetic resonance (PFG-NMR) for the cation and anion using 7Li and 19F resonant frequencies respectively. It was found that lithium ion diffusion was slow compared to the much larger fluorine anion likely resulting from a large solvation shell of the lithium. Lithium ion diffusion measurements exhibited two distinct diffusive species, whereas the fluorine ions exhibited only a single diffusive species. 相似文献
20.
ABSTRACT This paper is about INES, an intelligent, multimodal tutoring environment, and how we build a tutor agent in the environment that tries to be sensitive to the mental state of the student that interacts with it. The environment was primarily designed to help students practice nursing tasks. For example, one of the implemented tasks is to give a virtual patient a subcutaneous injection. The students can interact multimodally using speech and a haptic device under the guidance of the virtual embodied tutor. INES takes into account elements of the student's character and an appraisal of the student's actions to estimate the mental state of the student. This information is used to plan and execute the actions and responses of the tutor agent. 相似文献