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排序方式: 共有569条查询结果,搜索用时 12 毫秒
1.
Robert Brooke Manrico Fabretto Samuel Pering Eliza Switalska Lachlan Reeks Drew Evans Peter Murphy 《应用聚合物科学杂志》2015,132(26)
A study using three different pairs of electrochromic polymers (ECPs) synthesized onto plaques by means of a modified vapor phase polymerization (VPP) technique is presented. Restriction of the respective polymerization times, allowed both faster and slower polymerizing monomers to be controlled, and produced blended plaques with visually diffuse interfaces. The ECPs within the blended plaques retain their individual electrochromic behavior and when encapsulated into an electrochromic device, show outstanding optical switching performance with little degradation evident over 10,000 cycles, coupled with a switching time of the order of 1 second. Blends also allow multiple diffuse color changes within an electrochromic device, due to the difference in oxidation potentials of the individual ECPs, making them candidates for adaptive camouflage use. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42158. 相似文献
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This paper sets out to share BT's leadership and experience by determining the identity management opportunities and issues,
then document the lessons learnt in previous deployments and recommend strategies for all types and sizes of organisation.
Today's ICT environment has created a mixed approach to access management across sectors. Browser-based any time, anywhere,
anyone access, coupled with the business need to access more systems and services across a changing infrastructure of distributed
platforms and networked services, has changed the administrative landscape. Enterprises are being forced to add administrative
support staff or invest in technology-driven process change. At the same time, users are undergoing significant change, creating
new expectations in service quality. Moreover, regulatory bodies are demanding confirmation that processes granting access
are controlled and documented. In this world of increasing demands, complexity and expectation, the service management tools,
techniques and options available to improve user access management are as varied and numerous as the issues faced by management
in their deployment.
Identity management is widely heralded as an opportunity to improve the end user experience, reduce costs, improve security
and deliver regulatory compliance — but is often misunderstood. Projects regularly fail to achieve the expected benefits.
These failures are the result of expectations being inappropriately set, deployment of solutions turning out to be more complex
or taking longer than expected, and/or products selected before required functionality has been determined.
For the larger more mature organisations, or those organisations that are the amalgamation of mergers and acquisitions, the
dilemma is where to start and what approach to take. 相似文献
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Gouvier W. Drew; Sytsma-Jordan Sara; Mayville Stephen 《Canadian Metallurgical Quarterly》2003,48(3):175
Objective: To evaluate the effects of disability type, job complexity, and public contact on hiring decisions. Design and Participants: An Americans With Disabilities Act (ADA; 1990) fact sheet and matched resumes with vocational and medical histories including chronic mental illness, developmental disability, closed head injury, and back injury were provided to 295 undergraduate business-related majors, who rated the applicants' suitability for 2 job positions and work shifts. Results: Findings indicated disparities in ratings of employability as a function of disability type. Paired comparisons yielded complementary findings, with effects of disability type and Disability Type × Job Complexity, but no effects of public contact. Conclusions: Stereotyping and discrimination in employment decisions apparently persist, more than 10 years after the ADA. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Drew Michael R.; Yang Cynthia; Ohyama Tatsuya; Balsam Peter D. 《Canadian Metallurgical Quarterly》2004,30(3):163
Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A melt-extraction technique, using a sharpened molybdenum wheel, has been used to produce fine oxide ceramic fibres. Wetting of the molybdenum wheel by molten ceramic is a key parameter in the melt-extraction process. Two types of fibre are generally obtained, depending on the extraction speed. At very low wheel speed, fine and uniform fibres of high quality are produced. However, when the wheel speed exceeds a critical velocity, Rayleigh waves are formed on the free surface of the fibres. Moreover, the average fibre thickness first increases with the wheel velocity, then passes through a maximum, decreasing at high velocity. This thickness variation is discussed in terms of both surface tension and viscosity of the liquid ceramics. 相似文献
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This paper tests the assertion that experienced contractors are more competitive than inexperienced contractors by measuring the effect of experience on bidding competitiveness for building contracts procured by a regular client. Contractors are grouped into experienced and inexperienced contractors, and two levels of contractors’ experience are identified: (1) bidding experience only and (2) bidding plus construction experience. Results of two-sample t tests show that experienced contractors are more competitive than inexperienced contractors. Contractors’ competitiveness in respect of school contracts and other contracts are further compared in evaluating the relationship between the project type and experience effect. Experienced contractors are, on average, more competitive in competing for school contracts. It emerges that the factor of project type familiarity amplifies the experience effect. A comparison of experienced contractors’ competitiveness in bidding for (1) new building works and (2) alteration and extension works shows that the effect of experience would be more significant when contract works packages are highly standardized. 相似文献
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Mark S. Drew 《Solar Energy》1985,35(3):291-293