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161.
The purpose of this study is to better understand, from an explorative qualitative perspective, the motivations and practices of highly security-conscious users of mobile authentication, and their underlying mental models of those behaviours. Mobile authentication studies have largely overlooked the mindset of these users in the upper bound of security experience, who have considered their behaviour in terms of detailed knowledge of mobile authentication risk. Twenty IT professionals who self-identified as security-conscious mobile device users, many with decades of intensive security-specific experience, were interviewed for this study regarding their opinions and experiences with mobile device authentication and security. These users described usability and situational impairment issues, as well as a deep concern for their identity and data security arising from highly contextual combinations of distrust towards underlying technologies and situational risk. Derived implications for development of security methods adapted to these informed perspectives are discussed and will be the basis for follow-on research comparing these findings with everyday users. 相似文献
162.
Calcium carbonate‐filled syndiotactic poly(propylene) (CaCO3‐filled s‐PP) was prepared in a self‐wiping, co‐rotating twin‐screw extruder. The effects of CaCO3 of varying particle size (1.9, 2.8 and 10.5 μm), content (0–40 wt %), and type of surface modification (uncoated, stearic acid‐coated, and paraffin‐coated) on the crystallization and melting behavior, mechanical properties, and processability of CaCO3‐filled s‐PP were investigated. Non‐isothermal crystallization studies indicate that CaCO3 acts as a good nucleating agent for s‐PP. The nucleating efficiency of CaCO3 for s‐PP was found to depend strongly on its purity, type of surface treatment, and average particle size. Tensile strength was found to decrease, while Young's modulus increased, with increasing CaCO3 content. Both types of surface treatment on CaCO3 particles reduced tensile strength and Young's modulus, but improved impact resistance. Scanning electron microscopy (SEM) observations of the fracture surfaces for selected CaCO3‐filled s‐PP samples revealed an improvement in CaCO3 dispersion as a result of surface treatment. Finally, steady‐state shear viscosity of CaCO3‐filled s‐PP was found to increase with increasing CaCO3 content and decreasing particle size. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 201–212, 2004 相似文献
163.
A novel pattern recognition technique, support vector regression (SVR), has been introduced for linear structural parameter identification in a companion article. It is recognized that structural systems in general are designed to behave nonlinearly when subjected to extreme loading. Therefore SVR-based methods for nonlinear structural identification (SI) have been studied and they are summarized in this paper. The first method uses the SVR technique to identify nonlinear structural parameters, whereby the power parameter controlling the shape of the Bouc–Wen model is known. The second and third methods conduct nonlinear SI in the power parameter unknown condition, with the difference that the third method adopts a model selection strategy to enhance the nonlinear parameter estimation practicability. Five-story nonlinear structural systems whose restoring forces are expressed by the Bouc–Wen model are investigated to demonstrate the effectiveness of the SVR-based SI methods. Verification results show that the third method using the model selection strategy is the most efficient one for nonlinear structural parameter identification. 相似文献
164.
This paper addresses the question of how older adults’ experiences of home maintenance issues shape their opportunities to maintain ageing in place. We explore this question through a case study of ageing in place on Waiheke Island, near Auckland, New Zealand. We draw on in-depth interviews with 28 older adults aged 65 to 94, as well as participatory photo elicitation interviews and research journals conducted with 11 of these participants. We argue that older adults’ diverse personal circumstances and wider social contexts influence how home maintenance concerns are understood and addressed. We find that maintenance issues may cause stress and anxiety, thereby rupturing affective ties to place, limiting access to preferred identities and reducing well-being. Yet many feel connected to social networks and gain a positive sense of self and autonomy through participation in home maintenance tasks. Ultimately, how older adults experience their home maintenance issues influences their opportunities to maintain ageing in place. 相似文献
165.
Barnard Lucy; Stevens Tara; Siwatu Kamau Oginga; Lan William 《Canadian Metallurgical Quarterly》2008,1(3):169
A survey of a sample of faculty (N = 201) at a large, public university located in the Southwest was conducted to investigate whether differences in faculty attitudes toward diversity positively mediate faculty attitudes toward persons with disabilities. In addition, the current study examined whether differences in faculty attitudes toward diversity may be viewed as positively mediating the relationship between instructor characteristics and their attitudes toward persons with disabilities. This study concludes that faculty members may not be viewing disability as part of the greater construct of diversity with empirical evidence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Smith S Tang TB Terry JG Stevenson JT Flynn BW Reekie HM Murray AF Gundlach AM Renshaw D Dhillon B Ohtori A Inoue Y Walton AJ 《IET nanobiotechnology / IET》2007,1(5):80-86
The development of an implantable system designed to deliver drug doses in a controlled manner over an extended time period is reported. Key performance parameters are the physical size, the power consumption and also the ability to perform wireless communications to enable the system to be externally controlled and interrogated. The system has been designed to facilitate wireless power transfer, which is very important for miniaturisation as it removes the need for a battery. 相似文献
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Lacticin 3147 is a broad-spectrum bacteriocin produced by the food-grade organism Lactococcus lactis. Lacticin 3147 is active at a neutral pH and has been shown to be bactericidal to streptococci and staphylococci in vitro. The effectiveness of an intramammary teat seal formulation, and a teat seal containing lacticin 3147 was evaluated at drying off in 68 uninfected quarters of 18 cows. Following infusion of either teat seal or lacticin 3147 combined with teat seal, a deliberate infection challenge of Streptococcus dysgalactiae (approximately equal to 1.5 x 10(4) cfu per teat) was administered by direct inoculation into the teat sinus. During an 8-d experimental period following inoculation, 61% of control quarters and 6% of the treatment quarters either developed clinical mastitis or were shedding the challenge organism. Randomly amplified polymorphic DNA polymerase chain reaction genetic typing was used to confirm that both the new infections and the bacteria surviving in the teats at the end of the experiment were the challenge strain. The combination of teat seal and lacticin 3147 was well tolerated within the udder and elicited only a temporary increase in somatic cell count to 5.7 x 10(5)/ml (88 h after infusion) in a previously uninfected lactating udder quarter. Therefore, we concluded that this nonantibiotic approach to mastitis prevention may contribute to a reduction in the routine application of antibiotics at drying off in the future. 相似文献