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61.
Henk Tobias 《Network Security》2000,2000(6):9-11
As more and more organizations conduct business over the Internet, the need to securely identify users across the anonymity void of the Internet has never been more paramount. EEMA, the non-profit making trade organization for electronic business in Europe, has been at the forefront in the fight to create a legal framework for online identification, placing the issue high on the agenda at this year’s ISSE conference in October. 相似文献
62.
W-based versus latent variables spatial autoregressive models: evidence from Monte Carlo simulations
In this paper, we compare by means of Monte Carlo simulations two approaches to take spatial autocorrelation into account:
the classical spatial autoregressive model and the structural equations model with latent variables. The former accounts for
spatial dependence and spillover effects in georeferenced data by means of a spatial weights matrix W. The latter represents
spatial dependence and spillover effects by means of a latent variable in the structural (regression) model while the observed
spatially lagged variables are related to the latent spatial dependence variable in the measurement model. The simulation
results based on Anselin’s Columbus, Ohio, crime data set show that the misspecified latent variables approach slightly trails
the correctly specified classical approach in terms of bias and root mean squared error of the coefficient estimators. 相似文献
63.
This article discusses the consideration of factors involved in the selection of a system to provide process water, using ultrafiltration to treat surface water. The first part looks at on-site process water production from surface water for an Akzo Nobel Chemicals site in Amsterdam. The second part discusses UF membranes in such applications, and describes the development of the AquaFlex system. 相似文献
64.
Sven van der Gijp Johan E. ten Elshof Oliver Steigelmann Henk Verweij 《Journal of the American Ceramic Society》2000,83(10):2610-2612
The influence of mechanical stress and chemical homogeneity on the permittivity of BaTi0.9 Zr0.1 O3 ceramics prepared from mixed-oxide and hydrothermal powders was studied. To reduce stress, liquid-phase sintering was applied in conjunction with a low heating rate to stimulate the formation of large grains. The influence of chemical homogeneity was studied by variations in sintering temperatures and times. For both types of ceramics, the dielectric constant at the Curie temperature was influenced by both factors, but to a different extent. In the mixed oxide ceramic, chemical homogeneity played a more prominent role, while internal stress appeared to exert a larger influence in the hydrothermal ceramics. The dielectric constant at the Curie temperature could be increased by 5%–10% by an annealing treatment at 200°C, followed by slow cooling. 相似文献
65.
Physicochemical properties and amylopectin chain profiles of cowpea,chickpea and yellow pea starches
Junrong Huang Henk A. Schols Jeroen J.G. van Soest Zhengyu Jin Ellen Sulmann Alphons G.J. Voragen 《Food chemistry》2007,101(4):1338-1345
Starches from cowpea and chickpea seeds were isolated and their properties were compared with those of commercial yellow pea starch. Amylose contents were 25.8%, 27.2%, and 31.2%, and the volume mean diameter of granules, determined in the dry state, were 15.5, 17.9, and 33.8 μm for cowpea, chickpea and yellow pea starches, respectively. All three legume starches showed a C-type X-ray diffraction pattern and two-stage swelling pattern. Amylopectin populations were isolated and the unit chain profiles were analyzed by HPLC after debranching with pullulanase. The degree of polymerization (DP) of short chain populations was about 6–50 and the populations of long chain had a DP of 50–80. Cowpea showed a lower weight ratio of short:long chains than chickpea and yellow pea starches. The larger portion of long side chains in cowpea amylopectin can be correlated with a higher gelatinization temperature, greater pasting peak and a slight difference in crystalline structure found for cowpea starch. Chickpea and yellow pea starches exhibited similarity in unit chain profile of amylopectin as well as in gelatinization temperature and pasting profile, while they differed in amylose content, particle size and syneresis. It is assumed that the chain length distribution of amylopectin has a large influence on starch properties. 相似文献
66.
de Jong Peter J.; Merckelbach Harald; Arntz Arnoud; Nijmam Henk 《Canadian Metallurgical Quarterly》1992,101(4):724
20 treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by the behavioral treatment. In addition, untreated Ss were more confident about their contingency estimates than were treated Ss. The present results fit with earlier studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Stroebe Margaret; Stroebe Wolfgang; Schut Henk; Zech Emmanuelle; van den Bout Jan 《Canadian Metallurgical Quarterly》2002,70(1):169
Two longitudinal studies assessed whether disclosure of emotions facilitates recovery from bereavement. Study 1 tested prospectively over a 2-year period whether the extent to which bereaved persons talked about their loss to others and disclosed their emotions was associated with better adjustment to the loss of a marital partner. There was no evidence that disclosure facilitated adjustment. Study 2 randomly assigned recently bereaved individuals either to the Pennebaker writing task (J. W. Pennebaker & S. K. Beall, 1986) or to no-essay control conditions. The writing task did not result in a reduction of distress or of doctors visits either immediately after the bereavement or at a 6-month follow-up. Beneficial effects were not demonstrated for bereaved persons who had suffered an unexpected loss or who at the time of the study still expressed a high need for emotional disclosure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
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70.
Klánová J Diamond M Jones K Lammel G Lohmann R Pirrone N Scheringer M Balducci C Bidleman T Bláha K Bláha L Booij K Bouwman H Breivik K Eckhardt S Fiedler H Garrigues P Harner T Holoubek I Hung H MacLeod M Magulova K Mosca S Pistocchi A Simonich S Smedes F Stephanou E Sweetman A Sebková K Venier M Vighi M Vrana B Wania F Weber R Weiss P 《Environmental science & technology》2011,45(18):7617-7619