节假日期间面临的安全保护挑战

当重要的节日（如中国的春节和西方的圣诞节）到来之时，许多机构组织的大部分员工都休假了，业务通常在一段时间内完全停止，或最多只留下极少数员工来为其顾客提供服务。在欢庆的节假日里网络攻击者却不放假，因此对安全不能放松警惕。     

Arrhenius average temperature: the effective temperature for non-fatigue wearout and long term reliability in variable thermal conditions and climates

This paper presents a method of assessing the effective temperature essential for predicting the temperature acceleration of the wearout mechanisms (other than thermal fatigue) of electronic equipment. This is particularly important for equipment experiencing variable thermal conditions. The approach, based on weighting of thermal acceleration factors, leads to the Arrhenius average temperature T/sub eff/ given by (4). T/sub eff/ is related to wearout processes and allows one to compare predictions from the thermal design to results of accelerated testing. It has no relation to the maximum component temperature which influences functionality. The method is applicable to outside plant telecommunication equipment as well as in the automotive and aerospace industries. The effect of climate and design constraints on T/sub eff/ are discussed.     

Relation entre l'attachement et les interactions mère-enfant en milieu naturel et expérimental à l'age scolaire.

The purpose of the present study is to examine the relation between quality of mother-child interaction in a lab and home setting, and quality of attachment of school-age children. A second objective of the study is to evaluate the associations between quality of mother-child interactions, attachment and maternal psychosocial measures (social support, depression, and parental stress). Security of attachment (Separation-Reunion procedure, Main & Cassidy, 1988) and the quality of mother-child interaction was evaluated for a sample of 38 children (mean age = 6 years). Mothers also completed self-report measures for depression, stress, and social support. Concurrent to the lab assessment, quality of mother-child interaction was also evaluated during a home visit. Results indicated a strong association between interactive patterns in both settings. Moreover, interactive patterns differed in terms of attachment classification with secure children showing the most harmonious patterns and disorganized/controlling children showing the most dysfunctional patterns. Maternal psychosocial measures were not related to child security of attachment, but mothers of insecure children reported marginally more stress related to the child. Maternal psychosocial adjustment was, in part, related to dyadic mother-child interaction in the home and lab setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exploring the loss of semantic memory in semantic dementia: Evidence from a primed monitoring study.

An on-line primed monitoring study was used in an exploration of the nature of semantic memory loss in a patient (P.P.) with semantic dementia who showed a profound semantic impairment on a range of off-line tasks. Priming for pairs of words taken from a common category (e.g., cat-dog, spade-rake, ruby-emerald) was contrasted with that for word pairs from different categories that were related functionally (e.g., shampoo-hair, broom-floor, theater-play). Control participants showed robust priming for both types of semantic relation. P.P., in contrast, showed a normal priming effect for the functionally related conditions but no priming for category coordinates. This result suggests that P.P.'s semantic memory loss cannot be explained solely as a loss of stored representations or as a problem with deliberate controlled access to that information. Rather, elements of both explanations apply for different kinds of semantic information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Wideband radio imaging technique for multipath environments

A novel radio imaging technique with an application in the characterisation of indoor and urban wireless channels is described. The technique produces a visual representation of the multipath environment and has the capability of distinguishing between stationary and temporally varying components. Measurement and imaging techniques are described and sample results presented     

Use of a plasma reactor with a three-jet mixing chamber for processing of liquid toxic waste materials

We present a brief review and show the outlook for processing of toxic waste materials by a plasma method. We carried out experimental investigations of the processing of liquid toxic organic and organochlorine waste materials in a plasma reactor with a three-jet mixing chamber. Translated from InzhenernoFizicheskii Zhurnal, Vol. 70, No. 1, pp. 87–92, January–February, 1997.     

VSWR reduction for large millimeter-wave cassegrain radiotelescopes

Multiple reflections in large radiotelescopes used for astronomical spectroscopy cause characteristic modulations of the observed spectrum (“baseline ripple”). For a given mechanism, the magnitude of the effect depends primarily on the reflection coefficient, which for the most important paths is proportional to λ. Although ripple is thus generally negligible at mm-wavelengths, there are some instances where it may still be significant, and a recent experiment at the15 m James Clerk Maxwell Telescope was severely affected. We describe a technique which has proved effective in reducing the ripple to an acceptable level. The purpose of this research note is to draw this technique to the attention of the astronomical community. We calculate the reflection coefficient for a typical instrument and show that it can be greatly reduced over a very broad bandwidth by means of a tapered absorber in the centre of the secondary mirror. The graphical analysis of the tapered absorber also demonstrates that the scattering cones and circular absorbers widely used in radioastronomy donot in fact reduce the reflection coefficient significantly.     

Nucleation Processes Close to the Spinodal

Using an analytical equation of state (EOS) which describes a system that can exist in a liquid or vapor phase, a generalized Landau free-energy expansion around any spinodal point is constructed. For this simple model, the critical exponents associated with the spinodal line are obtained, and the model reduces to the usual expansion around the critical point as a particular case. The approach may become an interesting starting point to study phase separation mechanisms, such as nucleation and spinodal decomposition, far from the critical point. The decay of deeply quenched metastable states close to the spinodal through a nucleation process is analyzed and their mean lifetime is obtained. The results are compared with those obtained through the use of the usual Landau free-energy expansion around the critical point.     

Phosphorus-31 magnetic resonance brain spectroscopy of children at risk for a substance use disorder: preliminary results

The purpose of this exploratory investigation was to evaluate the heuristic potential of 31P magnetic resonance spectroscopy (MRS) in elucidating a neurobiologic component of the liability for a substance use disorder (SUD). We investigated 31P MRS spectra employing chemical shift imaging (CSI) derived from four distinct anatomic brain locations (i.e. frontal, occipital, right parietal, left parietal) in three groups of peripubertal children who are hypothesized to be at increasing levels of familial SUD risk. Specifically, we studied children with a positive paternal family history of SUD and a disruptive behavior disorder (DBD) diagnosis (SUD+/DBD+; n = 10), in contrast, to those with a positive paternal SUD history in the absence of other psychopathology (SUD+/DBD-; n = 13) and matched control children from normal families (SUD-/DBD-; n = 13). In addition, we examined neurocognitive tests of our subjects to determine any associations between cognitive capacities with regional 31P MRS spectra. The highest-risk sample (SUD+/DBD+) demonstrated a diminished proportion of phosphodiesters confined to the right parietal voxel. This right parietal phosphodiester proportion correlated only with the Information Scale score on a standard intelligence test for children. This suggested a relationship between general learning ability and motivation for academic achievement and right parietal physiology in the highest-risk sample. Variations in synaptic pruning could account for this observation.