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1.
Water Resources Management - In the context of climate stress, urbanisation and population growth, design and planning tools that assist in decentralised and environmental infrastructural planning...  相似文献   
2.
Administered dichotic digit tasks requiring free report and selective listening, respectively, to 20 6–16 yr old hyperactive children. Ss received methylphenidate before 2 experimental sessions and a placebo before 2 control sessions. The stimulant did not improve free-report performance significantly; rather it facilitated or impaired performance, depending on how it affected the order in which stimuli were reported. Similarly, medication had no effect on overall selective-listening performance, but it increased the difficulty of switching attention from one ear to the other. Results demonstrate that stimulants may act to maintain selective attention and to inhibit channel switching. Listening asymmetry, that is, right-ear superiority, was influenced by task variables but not by stimulant medication. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
The North Atlantic Refinery has three 5400-hp slow-speed induction motors driving reciprocating compressors for a Hydrogen plant. All motors were rewound on-site over the period of 1998-2002, using magnetic wedges as per the original design, and the motor protection was upgraded to microprocessor-type relays. In summer 2003, during routine maintenance, it was noted that these motors suffered substantial loss of slot magnetic wedges and had to be scheduled for rewedging over 2004-2006. This paper presents failure analysis, field measurements covering heat-run test results, and motor-performance and vibration analysis before and after motor rewedging work. This paper reviews the key factors for using magnetic versus nonmagnetic wedges in these applications and techniques available to predict loss of wedges. The use of a microprocessor relay for slow-speed induction motor protection is discussed, particularly, the thermal protection feature to address the cyclic-load pattern caused by the reciprocating compressor  相似文献   
4.
This paper reviews the literatures on housing and ontological security and the meaning of the home in order to derive specific examples of the psycho-social benefits of the home which can be assessed through empirical research. A postal survey measuring these psycho-social benefits was distributed to a random sample of adults in eight local authority districts in West Central Scotland. From the responses to the survey, three factors were constructed relating to the home as a haven, as a locus of autonomy and as a source of status for the occupants. Multivariate analysis showed that housing tenure is less important as an influence upon the attainment of psycho-social benefits from the home than the neighbourhood context and the incidence of problems with the home. Further, those factors negatively associated with psycho-social benefits appear to be more important than those factors positively associated with such benefits. This suggests that future research should focus on the fact that what detracts from psycho-social benefits may be more important than what contributes to them. A further important finding is that, after controlling for other influences, people living alone derive more benefits from the home as a haven and as a locus of autonomy than people in multi-person households.  相似文献   
5.
Radioactive hydroxyapatite was synthesized using 45Ca to evaluate the cariogenicity of oral streptococci. Discs prepared from it were suspended in media containing sucrose, then inoculated with Streptococcus mutans or Streptococcus sanguis. The radioactivity in the supernatant fluid was measured at specified time intervals. Released 45Ca in the supernatant fluids markedly increased in both species during the experimental period, while Strep. mutans showed much higher decalcification than Strep. sanguis. The present method would be useful for semi-quantitative evaluation of bacterial decalcification ability.  相似文献   
6.
Used a dual-task procedure as a measure of speech lateralization in 151 normal, right-handed, 3–12 yr old children. Ss engaged in unimanual finger tapping with and without concurrent speech. It was hypothesized that if speech is left lateralized, talking should disrupt right-hand tapping (an instance of intrahemispheric interference) more than left-hand tapping (an instance of interhemispheric interference). Results for 2 different verbal tasks show the predicted overall asymmetry but no developmental trend in degree of asymmetry. The data suggest that lateralization is as marked in young children as in older children. About 70% of the Ss showed the predicted effect; there was no significant change in incidence as a function of grade level. Analyses of verbal production indicated that the performance asymmetry could not be attributed to an asymmetrical trade-off between talking and tapping. No sex differences in performance asymmetry were found. The results contradict the traditional model of progressive lateralization but corroborate the developmental invariance frequently observed using perceptual measures of language lateralization. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Children with congenital hydrocephalus, children with attention deficit-hyperactivity disorder, and normal controls were evaluated with measures of focused attention (Visual Orienting and Detection Task), sustained attention (continuous performance test), and attention shifting (Wisconsin Card Sorting Test). Components from these tasks have been linked to attention systems mediated by anterior or posterior brain networks. Children with congenital hydrocephalus showed an inability to focus and shift attention, which specifically implicated impairment of the disengage and move components of the posterior brain attention system. Children with attention deficit- hyperactivity disorder displayed the expected performance patterns on measures of focused attention once their difficulties with sustained attention were taken into account. However, they showed problems with shifting and sustaining attention, which are commonly associated with the anterior brain attention system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The present author agrees with the suggestions by P. J. Caplan et al (see record 1986-10956-001) that sex differences in average performance on spatial tasks are often modest in magnitude and inconsistent from one task to another and that spatial ability is not a unitary construct; however, their contentions that sex differences in spatial abilities are nonexistent and that the concept of spatial abilities is not sufficiently valid as to allow meaningful investigation of sex differences are challenged. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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10.
A concurrent-task paradigm was used to investigate age-related differences in the attentional capacity of 92 right-handed adults. Young, middle-aged, and elderly Ss were compared as they performed speeded, unimanual finger tapping with and without concurrent silent reading, speaking, and maze completion. There were 2 levels of difficulty for each cognitive task. The decrement in tapping rate from the single- to dual-task condition increased linearly with age. Concurrent-task tapping was slowed more by difficult than by easy tasks, and difficult tasks had a disproportionately disruptive effect on the concurrent performance of elderly Ss. The heightened vulnerability of the elderly to concurrent-task effects cannot be attributed parsimoniously to either general slowing or diminution of a specific resource. Instead, the results suggest a reduction in a general-purpose processing resource with increasing age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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