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11.
Investigated burden experienced by 60 spouses and 71 parents who served as primary caregivers to individuals with traumatic brain injury (BI). Burden levels, as assessed by the Questionnaire on Resources and Stress (QRS-SF), were compared for spouses and parents. Both parents and spouses exhibited high levels of burden. Relative to spouses, parents reported significantly greater burden related to lifespan care. Spouses reported significantly less personal reward than did parents. The presence of social aggression and cognitive disability in the individual with BI was found to have a greater association with subjective burden of caregivers than was the presence of physical disability or injury severity. Results of previous studies with QRS-SF scores show that the responsibility assumed by spouses and parents of persons with BI was as great as that experienced by families of people with severe chronic physical disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
We analyze the impact of a time-varying Rayleigh-fading channel on the performance of an Alamouti transmit-diversity scheme. We propose several optimal and suboptimal detection strategies for mitigating the effects of a time-varying channel, and derive expressions for their bit-error probability as a function of the channel correlation coefficient /spl rho/. We find that the maximum-likelihood detector that optimally compensates for the time-varying channel is very tolerant to time-varying fading, attaining full diversity order even for the extreme case of /spl rho/=0. In contrast, although lower in complexity, the suboptimal schemes suffer a diversity penalty and are thus suitable only for slowly fading channels.  相似文献   
13.
Three experiments, with 98 undergraduates, investigated the effects of increasing task difficulty and noise intensity on postnoise persistence on the Feather tolerance for frustration puzzles. In Exp I, greater persistence occurred both after exposure to moderate noise levels (55 db [A]) and an easy perceptual-motor task and after high noise levels (90 db [A]) and a more difficult task. The same pattern of persistence was obtained in Exp II, with more attempts to solve the Feather puzzles occurring after moderate noise and an easy cognitive task and after loud noise and a more difficult cognitive task. In Exp III, a modified Feather task was presented with instructions to determine solvability. A similar U-shaped relationship was obtained, with longer correct response times to unsolvable puzzles following low noise and high noise. Such aftereffect patterns are more easily explained as the result of residual arousal than of frustration tolerance. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
Book review     
Published in 1989, 585 pages, $180; Available from the American Institute of Chemical Engineers, 345 East 47th St., Publication Sales Department, New York, NY 10017.  相似文献   
15.
The authors describe their perspectives as a psychologist married couple and discuss some of the major trends that have affected their work in the last years, including the women's movement and new developments in the field of psychology. They note both positive and negative changes from the last 2 decades. Whereas there are many more new and exciting opportunities for psychologists today, there are also more pressures, more stringent training and credentialing requirements, more competition, and less mobility. Also discussed are some advantages to being married to another psychologist, including understanding each other's roles, combining social and professional lives, and expanding professional networks. They look to the future of psychology with optimism and hope that by examining and changing some of the restrictions on psychologists today, the field of professional psychology can be made more rewarding for future psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
A few years ago, Sun Microsystems CEO Scott McNealy created uproar by declaring: ‘You have zero privacy. Get over it.’ ( Sprenger, 1999 ) The question, at least for Americans, is did the 11 September terrorist attacks – and the response to them – prove him right? Is privacy really dead?  相似文献   
17.
The intensity and frequency chirp of picosecond pulses from a self-seeded gain-switched Fabry-Perot laser diode have been directly measured using the technique of frequency-resolved optical gating. Measurements over an output sidemode suppression ratio (SMSR) range of 15-35 dB show that higher SMSR's are associated with an increasingly linear frequency chirp across the output pulses. This complete pulse characterization allows the conditions for optimum pulse compression to be determined accurately, and indicates that transform-limited, pedestal free pulses can be obtained at an SMSR of 35 dB  相似文献   
18.
The morphology of surfaces of several ceramic materials has been examined using transmission electron microscopy. The approach used was to prepare a sample for examination in the microscope, carefully clean it, and then heat-treat it. In the case of the oxides studied (alumina and spinel) the samples were heated in air; the non-oxides (α-SiC and β -SiC) were annealed under vacuum. The morphology in all but one case was such that the surface faceted parallel to the nearest low-index plane to give well-defined terraces; these were separated by ledges which also tended to facet parallel to the traces of low-index planes. The exception was the {1100} alumina surface, which appears to be unstable in air at temperatures close to 1400°C. A computer program using a multislice approach was used to estimate the height of the steps on the (0001) surface; the step heights appear to be multiples of the c lattice parameter. A reconstruction of this surface as a result of this heat treatment is also proposed.  相似文献   
19.
Corrosion-related failures in electric power plants often stimulate research aimed at understanding the cause of the failures and at developing cost-effective corrosion control options. This paper describes some of the success stories. Over the last few years, EPRI has helped solve several aqueous corrosion problems using the following approaches: materials selection, coatings, water chemistry control, residual stress modification and corrosion monitoring. These approaches were applied successfully to flue gas desulfurization systems, low pressure steam turbines and boiling water reactor piping. A measure of the success of these corrosion control options is the cost savings of over $570 million documented by only seven of EPRI's over 700 utility members after applying these techniques.  相似文献   
20.
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