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81.
Many organisations suspect that their internal security threat is more pressing than their external security threat. The internal threat is predominantly the result of poor user security behaviour. Yet, despite that, security awareness programmes often seem more likely to put users to sleep than to improve their behaviour. This article discusses the influences that affect a user's security behaviour and outlines how a well structured approach focused on improving behaviour could be an excellent way to take security slack out of an organisation and to achieve a high return for a modest, low-risk investment. 相似文献
82.
Peer-assisted learning interventions with elementary school students: A meta-analytic review. 总被引:1,自引:0,他引:1
Rohrbeck Cynthia A.; Ginsburg-Block Marika D.; Fantuzzo John W.; Miller Traci R. 《Canadian Metallurgical Quarterly》2003,95(2):240
A meta-analytic review of group comparison design studies evaluating peer-assisted learning (PAL) interventions with elementary school students produced positive effect sizes (ESs) indicating increases in achievement (unweighted mean ES = 0.59, SD = 0.90; weighted ES, d = 0.33, p 相似文献
83.
Investigation of the thermal, mechanical, and fracture properties of alumina-epoxy composites 总被引:1,自引:0,他引:1
A combination of dynamic shear rheology, thermomechanical analysis (TMA), scanning electron microscopy (SEM), Near-Edge X-ray Absorption Fine Structure (NEXAFS), and fracture toughness testing was utilized to characterize the thermal, mechanical, chemical, and fracture properties of alumina (α-Al2O3)-filled epoxy resins as a function of average filler size, size distribution, particle shape, loading, and epoxy crosslink density. In general the cured properties of the filled composites were robust. Small changes in particle size, shape, and size distribution had little impact on the final properties. Resin crosslink density and filler loading were the most critical variables, causing changes in all properties. However, most applications could likely tolerate small changes in these variables also. SEM and NEXAFS characterization of the fracture surfaces revealed that the fracture occurs at the filler interface and the interfacial epoxy composition is similar to the bulk resin, indicating a weak epoxy-alumina interaction. These results are critical for implementation of particulate-filled polymer composites in practical applications because relaxed material specifications and handling procedures can be incorporated in production environments to improve efficiency. 相似文献
84.
85.
Piers Wilson 《Network Security》2003,2003(8):16-18
Rogue servers are a constant threat and pose a variety of problems for the IT security team. This article summarises the threats that come from not managing rogue servers and gives prevention and detection tips. 相似文献
86.
The ears of lizards are highly directional. The directionality is generated by strong acoustical coupling of the eardrums.
A simple lumped-parameter model of the ear followed by binaural comparisons has been shown to perform successful phonotaxis
in robot implementations. However, such a model will produce localization errors in the form of response bias if the ears
are asymmetrical. We have evaluated how large errors are generated by asymmetry using simulations of the ear model in Mathematica
5.2. The study shows that the effect of asymmetry is minimal around the most directional frequency of the ear, but that biases
reduce the useful bandwidth of localization.
This work was presented in part at the First European Workshop on Artificial Life and Robotics, Vienna, Austria, July 12–13,
2007 相似文献
87.
88.
John Seifert Angela Frelich Linda Shecterle John St Cyr 《Journal of the International Society of Sports Nutrition》2008,5(1):1-5
D-ribose, a naturally occurring pentose carbohydrate, has been shown to replenish high- energy phosphates following myocardial ischemia and high intensity, repetitive exercise. Human studies have mainly involved short-term assessment, including potential toxicity. Reports describing adverse effects of D-ribose with prolonged ingestion have been lacking. Therefore, this study assessed the toxicity of extended consumption of D-ribose in healthy adults. Nineteen subjects ingested 20 grams/Day (10 grams, twice a Day) of ribose with serial measurements of biochemical and hematological parameters at Days 0, 7, and 14. No significant toxic changes over the 14-day assessment period occurred in complete blood count, albumin, alkaline phosphatase, gamma glutamyltransferase, alanine amiotransferase, and aspartate aminotransferase. However, D-ribose did produce an asymptomatic, mild hypoglycemia of short duration. Uric acid levels increased at Day 7, but decreased to baseline values by Day 14. D-ribose consumption for 14 days appears not to produce significant toxic changes in both hematological and biochemical parameters in healthy human volunteers. 相似文献
89.
Argues that children's failure on one of Piaget's best known tasks, conservation of solid quantity, reflects ignorance of physical properties rather than inadequate reasoning ability. The evidence for conservation itself, seen from the child's position, is analyzed. It is emphasized that children can learn and enjoy the concepts and methods of physics at much earlier ages than current orthodoxies would indicate. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
John Hemp 《Flow Measurement and Instrumentation》1994,5(4):247-253
In this paper a fuller and clear derivation of the weight vector theory of Coriolis mass flowmeters is given indicating its potential for the prediction of velocity profile effects in both the traditional kind of meter (vibrating tube) and the compact kind (vibrating element inside a duct). 相似文献