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61.
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Chong Shen Wencai Du Robert Atkinson Kae Hsiang Kwong 《Wireless Personal Communications》2012,62(2):329-361
We propose a dynamic mobility management framework for Internet Protocol version 6 (IPv6) and policy enforcement enabled heterogenous
wireless networks. Policies and policy rules are defined depending on network infrastructure facilities, service agreements
and negotiation results. Each traffic is coupled with an identifiable traffic flow while the heterogenous interface flow bindings
are regulated by polices. The network selection, flow distribution, handovers and mobility procedures are flexible and we
propose to improve the decision making via Multiple Attributes Decision Making (MADM). Techniques considered in the framework
include the IPv6 based Network Mobility (NEMO), multihoming capability, transparent vertical handovers, horizontal handovers
and dynamic policy enforcement matching process to improve the Quality of Service (QoS), Quality of Experience (QoE) and ubiquitous
connectivity. A experiment testbed and simulation models have been constructed to verify the mobility framework performance
in a heterogeneous WiFi, WiMax and UMTS hybrid environment. 相似文献
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The interface fracture toughness of thermal barrier coatings (TBCs) on high-pressure turbine blades manufactured by electron beam physical vapour deposition was measured by a cross-sectional indentation (CSI) method. Scanning electron microscopy and luminescence mapping were employed to reveal that coating delamination induced by CSI was predominantly along the thermally grown oxide–bond coat interface and the shape of the delaminated area was approximately semicircular. The critical energy release rate (Gc) for delamination was calculated based on a clamped circular plate model. Analysis of the stored energy release revealed that the residual stresses in the coating do not contribute to the total energy release rate provided that the delaminated area of the coating does not buckle. Therefore, for this method, detailed information of residual stresses is not necessary for the determination of interface fracture toughness. However, intercolumnar microfracture and shear displacement in the YSZ top coat can lead to significant overestimation of the interface fracture toughness in some situations. A method of specimen preparation is described to inhibit these effects. The interface fracture resistance of the TBCs was found to be 29 ± 9 J m?2 after between 35 and 100 thermal cycles (from room temperature to 1150 °C with 1 h duration). 相似文献
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Anthony C. Atkinson 《技术计量学》2013,55(3):616-618
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The occurrence of accidents and injuries continues to be a major problem in construction worldwide. Even though accident statistics have been improving in most markets there are significant areas requiring further attention. The extent of integrated working between designers and constructors may be an instrumental factor. A comparison is undertaken of the accident performance of 55 large construction projects in the UK, with varying levels of design/construction integration as represented by procurement path. Although a statistical relationship between high levels of integration and low levels of accidents was weak, a follow‐up interview study provided strong support, suggesting that a lack of significance was related to the unreliability of the statistics available. The interview study also indicated reasons for this link. A key element in improved safety was seen to be better communications and a more positive relationship between designers and constructors. Further research into designing for safety for all procurement paths is recommended. 相似文献
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Homayun K. Navaz Ali Zand Theresa Atkinson Albert Nowakowski Amir Gat Sari Paikoff 《American Institute of Chemical Engineers》2014,60(6):2346-2353
A computational fluid dynamics model based on a finite difference solution to mass and momentum conservation equations (Navier–Stokes equations) for a liquid droplet transport between two porous or nonporous contacting surfaces (CSs) is developed. The CS dynamic (equation of motion) and the spread of the incompressible liquid available on the primary surface for transfer are coupled with the Navier–Stokes equations. The topologies of the spread dynamic between and inside both surfaces (primary and CSs) are compared with experimental data. The amount of mass being transferred into the CS, predicted by the model, is also compared to the experimental measurements. The impact of the initial velocity on the spread topology and mass transfer into the pores is addressed. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2346–2353, 2014 相似文献
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Zhang Duyao Atkinson Helen V. Dong Hongbiao Zhu Qiang 《Metallurgical and Materials Transactions A》2017,48(10):4701-4712
Metallurgical and Materials Transactions A - There is a need to extend the application of semi-solid processing (SSP) to higher performance alloys such as 319s (Al-Si-Cu-Mg) and 201 (Al-Cu-Ag). The... 相似文献
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