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41.
Recent years have witnessed major governmental initiatives regarding critical infrastructure protection (CIP). During that same time, critical infrastructures (CIs) have undergone massive institutional restructuring under the headings of privatization, deregulation and liberalization. Little research has gone into understanding the interactions between these two developments. In this article, we outline the consequences of institutional restructuring for the changing ways in which CIs ensure the reliability and security of their networks and services. Neither Normal Accident Theory nor High‐Reliability Theory can account for reliability under these conditions. We then investigate the implications of these findings for CIP. 相似文献
42.
Jean Poerre 《钢铁》2003,38(Z1):101-103
全球变暖给钢铁工业带来了巨大的挑战,挑战涉及使用碳的多少和能量利用率.低强度生产可以短期内达到减轻排放,使处于京都协议要求的水平.从中期看,更多地使用废钢也有助于减轻排放.但是为了实现更多地减少温室气体GHG的排放,也即等于实现京都协议之后的排放目标,钢铁工业必须设想有一个新的生产面貌,这形成了未来时期对它的最大挑战.碳的收集和吸收,碳使用中的代用剂,工艺流程中绿色来源的电和氢的应用,这些在未来10年中是必须要发展的,希望通过广泛地国际合作加以实现. 相似文献
43.
Cognitive Operations in the Generation Effect on a Recall Test: Role of Aging and Divided Attention.
Generation effect (generated words are better memorized than read words) of anagrams, rhymes, and associates of target words was examined in young, elderly, and very old subjects. Experiments 1 and 2 showed that only young subjects benefit from the generation effect in a free-recall test when the rule is of a phonological nature. Experiments 3, 4, and 5 showed that the generation effect of rhymes was due to a resources-dependent self-initiated process. Experiments 4 and 5 showed that in a divided-attention situation, generation effect of rhymes is not significant in young subjects, but that the generation effect of semantic associates remains significant for both groups (Experiment 5). The results are discussed within the environmental support framework and the transfer-appropriate processing framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Trust for Ubiquitous,Transparent Collaboration 总被引:1,自引:0,他引:1
In this paper, trust-based recommendations control the exchange of personal information between handheld computers. Combined with explicit risk analysis, this enables unobtrusive information exchange, while limiting access to confidential information. The same model can be applied to a wide range of mobile computing tasks, such as managing personal address books and electronic diaries, to automatically provide an appropriate level of security. Recommendations add structure to the information, by associating categories with data and with each other, with degrees of trust belief and disbelief. Since categories also in turn confer privileges and restrict actions, they are analogous to rôles in a Rôle-Based Access Control system, while principals represent their trust policies in recommendations. Participants first compute their trust in information, by combining their own trust assumptions with others' policies. Recommendations are thus linked together to compute a considered, local trust assessment. Actions are then moderated by a risk assessment, which weighs up costs and benefits, including the cost of the user's time, before deciding whether to allow or forbid the information exchange, or ask for help. By unifying trust assessments and access control, participants can take calculated risks to automatically yet safely share their personal information. 相似文献
45.
The catalytic activity of fresh Pd and Pt catalysts supported on γ-alumina in the complete oxidation of CH4 traces under lean-burn conditions was studied in the presence or the absence of water or H2S. Steam-aged catalysts were also studied in order to simulate long-term ageing in real lean-burn natural gas fuelled vehicles (NGVs) exhaust conditions. Without water or H2S added to the feed, Pd catalysts exhibit a superior catalytic activity in methane oxidation compared to Pt ones, whatever the catalysts were fresh or aged. The addition of 10 vol.% water vapour to the feed strongly affects the activity of the fresh Pd catalyst, thus being only slightly more efficient than the fresh Pt one. H2S has a strong poisoning effect on the catalytic activity of Pd catalysts, while Pt catalysts are more resistant. The fresh H2S-poisoned Pd/Al2O3 catalyst was studied by TPD in O2/He. Poisoning species decompose above 873 K as SO2 and O2 in relative concentrations consistent with the decomposition of surface sulphate species. However, a treatment in O2/He at temperatures as high as 923 K does not allow the complete regeneration of the catalytic activity of H2S-poisoned Pd/Al2O3. A mechanism involving the poisoning of PdO by sulphate species is proposed. Different diffusion processes by which these sulphate species can migrate back and forth between PdO and the support, depending on the experimental conditions, are suggested. 相似文献
46.
Shiffman Saul; Paty Jean A.; Gnys Maryann; Kassel Jon D.; Elash Celeste 《Canadian Metallurgical Quarterly》1995,14(4):301
From previous studies, chippers (very light, long-time cigarette smokers) seem not to be nicotine dependent, despite decades of smoking. The effect of tobacco deprivation on chippers' withdrawal reactions was examined. Matched groups of 26 chippers and 25 regular smokers were studied while abstaining or smoking for 2-day blocks, with assessments administered 5 times daily by palm-top computers. As hypothesized, chippers showed no changes as a result of nicotine deprivation. In contrast, regular smokers demonstrated distinct changes in craving, mood, arousal, and sleep disturbance. The computers also tested participants' cognitive performance. Unlike chippers, regular smokers' performance on complex tasks was slower under deprivation; the effect could not be explained by changes in motor performance or simple reaction time. Results suggest performance may have been improved by nicotine rather than worsened by withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
We present a general method and a toolkit for designing, implementing and visualizing distributed algorithms. We make use of the high level encoding of distributed algorithms as graph rewriting systems. The result is a unified and simple framework for describing, implementing and visualizing a large family of distributed algorithms. 相似文献
48.
Loranger Michel; Pépin Michel; Gignac Guy; Benoit Geneviève 《Canadian Metallurgical Quarterly》1995,36(1):59
Presents results of 3 studies on the psychometric properties of the LP-ABC (M. Loranger and M. Pépin, 1993), a French-language instrument for assessing general functioning in adults with mental retardation. The studies involved a total of 299 male and female Canadian adults with mental retardation. Results confirm the internal consistency, construct validity, criterion validity, discriminant validity, interrater reliability, and test–retest reliability of the LP-ABC. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Emmanuel. Delamarche Bruno. Michel Hans A. Biebuyck Christoph Gerber 《Advanced materials (Deerfield Beach, Fla.)》1996,8(9):719-729
Self-assembled monolayers (SAMs) of alkanethiols and disulfides on gold form organic interfaces with properties largely controlled by the end groups of the molecules composing the film. SAMs provide a unique link between the science of organic surfaces and technologies that seek to exploit their adaptable character. Many techniques are useful for probing the structure of SAMs although only scanning tunneling microscopy (STM) at picoamperes reveals the details of the packing of their end groups at the sub-angstrom level. This review demonstrates that STM effectively tests new types of control over the microscopic structure–property relationships characteristic of SAMs on gold that should prove useful to their application. 相似文献
50.