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1.
Reports the results of a 3-wave longitudinal study of a sizable, regionally representative sample of both noncustodial and custodial parents interviewed initially before their divorce was final. A model was tested that predicted the noncustodial parent's postdivorce contact with the child and the payment of child support from a series of factors related to a social exchange orientation. This orientation highlights the noncustodial parent's implicit calculation of the rewards vs the costs of continuing involvement and support of the child. It was found that noninvolvement was, in general, well-predicted, both cross-sectionally and longitudinally, by the model. The most powerful factor in the model was the noncustodial parent's perception that he or she had some control over the child's upbringing. Among fully employed noncustodial parents who reported high perceived control, there was an excellent record of involvement and child support payment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The effects of the nature of the polyols used in polyurethane (PUR) synthesis on the structural transformations after ageing by UV irradiation has been studied. The investigations were performed on PUR prepared from polyester and polyether diol oligomers. The characterization of the samples before and after ageing in view of the structural changes, which influence the course of the photooxidative degradation and photocrosslinking as well as in view of changes of mechanical properties has been done. Comparative investigations were performed by spectroscopic and viscometric measurements. The results show pronounced heterogeneity of the degradative reactions, including the existence of crosslinking processes and producing thus very inhomogeneous polymeric material. The course and the intensity of photooxidative degradation of PUR differ together with changes of mechanical properties depending whether polyester or polyether polyol have been used. The processes of photooxidative degradation is less expressed in polyesterurethane then in polyurethane based on polyether, under the same conditions of experiments. Different structures of polyester diols caused the various ageing behaviour of PUR too.  相似文献   
3.
Revenue-collection data from toll roads allow for accurate estimates of miles driven by vehicle type and, when combined with crash data, valid estimates of crash involvements per mile driven. Data on vehicle-miles traveled and collisions were obtained from toll road authorities in Florida. Kansas, and New York. In addition, state crash files and published vehicle-miles of travel were obtained for toll roads in Illinois. Indiana, Ohio, and Pennsylvania. Large commercial motor vehicles were significantly underinvolved in single-vehicle crashes on all state toll roads. In five states, commercial motor vehicles were significantly overinvolved in multiple-vehicle crashes relative to passenger vehicles; the exceptions were Kansas, where they had significantly lower multiple-vehicle involvement rates, and Indiana. where there were no significant differences in multiple-vehicle involvements by vehicle type. The risk of commercial motor vehicle involvement in multiple-vehicle crashes resulting in deaths or serious injuries was double that of passenger vehicles in the two states (Ohio and Pennsylvania) that identified serious injuries. Whether crash rates, on toll roads of commercial motor vehicles are higher or lower than those of passenger vehicles appears to depend on the type of crash, specific toll road. and traffic density.  相似文献   
4.
There is public concern about the magnitude of the problem of large truck crashes in the US. Fatalities in large truck crashes have not declined much; however, more large trucks are driving more miles than ever before while fatalities per mile driven have dropped substantially. This study examined how the public health burden of large truck crashes versus the risk per unit of travel has changed over 25 years.The present study focused on the US vehicle occupants in fatal crashes involving a large truck during 1975-1999. Occupant fatalities per 100000 population, per 10000 licensed drivers, per 10000 registered trucks and per 100 million vehicle-miles of travel (VMT) were calculated to determine trends in occupant deaths in large truck crashes.In 1999, large truck crashes resulted in 3916 occupant deaths in passenger vehicles and 747 in large trucks. Passenger vehicle occupant deaths in large truck crashes per 100000 population have increased somewhat since 1975 (1.28 in 1975 and 1.44 in 1999). There have been appreciable declines in occupant deaths per truck VMT since 1975, but the percentage reduction has been greater for occupants of large trucks (67%) than for passenger vehicle occupants (43%). However, truck drivers are at elevated risk of dying relative to their numbers in the workforce. Overall large truck involvements in fatal crashes per truck VMT decreased more than passenger vehicle involvements per passenger VMT (PVMT; 68% versus 33% decreases for single-vehicle crashes and 43% versus 23% for multiple-vehicle crashes). Large truck involvement in fatal crashes has dropped substantially when measured per unit of travel, but the public health burden of large truck crashes, as measured by deaths per 100000 population, has not improved over time because of the large increase in truck mileage. Research is needed on measures to better protect both occupants of large trucks and passenger vehicle occupants colliding with them.  相似文献   
5.
Age-related cognitive differences may be due, in part, to difficulties using task-relevant context in a proactive manner. Two studies evaluated different methods for increasing older adults' use of context in the AX-Continuous Performance Task (H. E. Rosvold, A. F. Mirsky, I. Sarason, E. D. Bransome, & L. H. Beck, 1956), which evaluates components of context processing. The results suggest that (a) age differences in the use of context are not due to reduced access to cue information, (b) directed strategy training made older adults' context processing performance more like that of young adults, and (c) similar performance changes could be observed with less directed instruction and extended practice. These results suggest that age-related differences in context processing can be ameliorated by directed strategy training or extended practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
84 university counseling center clients (61 women and 23 men) self-reporting childhood physical, sexual, or emotional abuse (n?=?30) or no childhood abuse (n?=?54) completed 3 measures of psychological functioning. Multivariate analysis of variance revealed that clients reporting abuse were more depressed (with the mean Beck Depression Inventory score in the borderline clinical depression range), had more symptomatology (with the mean Global Severity Index of the Brief Symptom Inventory at about the average level of a psychiatric outpatient population), and scored higher on the Borderline Personality scale of the Millon Clinical Multiaxial Inventory (with the mean base-rate score near the cutoff score for presence of borderline personality features). 19 clients reporting emotional abuse only did not differ on any measure from 11 clients reporting sexual or multiple forms of abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
A neglected question regarding cognitive control is how control processes might detect situations calling for their involvement. The authors propose here that the demand for control may be evaluated in part by monitoring for conflicts in information processing. This hypothesis is supported by data concerning the anterior cingulate cortex, a brain area involved in cognitive control, which also appears to respond to the occurrence of conflict. The present article reports two computational modeling studies, serving to articulate the conflict monitoring hypothesis and examine its implications. The first study tests the sufficiency of the hypothesis to account for brain activation data, applying a measure of conflict to existing models of tasks shown to engage the anterior cingulate. The second study implements a feedback loop connecting conflict monitoring to cognitive control, using this to simulate a number of important behavioral phenomena. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
OBJECTIVE: To determine the risk of motor vehicle occupant deaths per unit of travel for Hispanic, non-Hispanic black, and non-Hispanic white children (aged 5-12 years) and teenagers (aged 13-19 years). DESIGN: Comparison of 1989 to 1993 motor vehicle occupant death rates of children and teenagers by race, ethnicity, and sex by using data on mortality from the National Center for Health Statistics, travel data from the 1990 Nationwide Personal Transportation Survey, and 1990 US census data. RESULTS: Among children 5 to 12 years old, race/ ethnicity differences per 100000 persons were unremarkable, but per billion vehicle-miles of travel, the rates were 14 for non-Hispanic blacks, 8 for Hispanics, and 5 for non-Hispanic whites. Among teenagers aged 13 to 19, the rates per 100000 persons were highest for non-Hispanic whites; however, the rates per billion vehicle-miles were 45 for Hispanics, 34 for non-Hispanic blacks, and 30 for non-Hispanic whites. Black and Hispanic male teenagers had substantially higher death rates per billion vehicle-miles of travel than either white male teenagers or female teenagers in any racial/ethnic group. CONCLUSIONS: Black and Hispanic children and teenagers are at higher risk of dying in motor vehicle crashes when they travel. Greater public health attention is needed to address these increased risks.  相似文献   
9.
Interference is reduced in mostly incongruent relative to mostly congruent lists. Classic accounts of this list-wide proportion congruence effect assume that list-level control processes strategically modulate word reading. Contemporary accounts posit that reliance on the word is modulated poststimulus onset by item-specific information (e.g., proportion congruency of the word). To adjudicate between these accounts, we used novel designs featuring neutral trials. In two experiments, we showed that the list-wide proportion congruence effect is accompanied by a change in neutral trial color-naming performance. Because neutral words have no item-specific bias, this pattern can be attributed to list-level control. Additionally, we showed that list-level attenuation of word reading led to a cost to performance on a secondary prospective memory task but only when that task required processing of the irrelevant, neutral word. These findings indicate that the list-wide proportion congruence effect at least partially reflects list-level control and challenge purely item-specific accounts of this effect. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
Fluid intelligence (gF) and working memory (WM) span predict success in demanding cognitive situations. Recent studies show that much of the variance in gF and WM span is shared, suggesting common neural mechanisms. This study provides a direct investigation of the degree to which shared variance in gF and WM span can be explained by neural mechanisms of interference control. The authors measured performance and functional magnetic resonance imaging activity in 102 participants during the n-back WM task, focusing on the selective activation effects associated with high-interference lure trials. Brain activity on these trials was correlated with gF, WM span, and task performance in core brain regions linked to WM and executive control, including bilateral dorsolateral prefrontal cortex (middle frontal gyrus; BA9) and parietal cortex (inferior parietal cortex; BA 40/7). Interference-related performance and interference-related activity accounted for a significant proportion of the shared variance in gF and WM span. Path analyses indicate that interference control activity may affect gF through a common set of processes that also influence WM span. These results suggest that individual differences in interference-control mechanisms are important for understanding the relationship between gF and WM span. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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