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991.
To evaluate cognitive-interference, reassertion, and reaction-to-performance models of test anxiety, 82 university students completed the Test Anxiety Scale, provided state measures of anxiety just before and after a course examination, described their preparation for the test, and reported thought content and state anxiety up to 6 times during the test. Test Anxiety Scale scores were predictive of pre- and posttest state anxiety but not performance or problem-solving thought frequency during the test. Thought content was significantly but weakly correlated with performance, which was well correlated with posttest state anxiety but not with pretest anxiety. Pretest state anxiety was virtually uncorrelated with posttest state anxiety, with the correlations gradually declining during the test. Question-answering thought content correlated inversely with anxiety during the test. There was no group for whom anxiety appeared to facilitate performance. Preparation correlated only with performance. Results appear inconsistent with a cognitive-interference interpretation of test anxiety and suggest that, in the naturalistic setting used, anxiety is more clearly an effect than a cause of poor performance. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Re‐ignition behaviour of charred solid fuels after extinction by water is studied. In this communication the effect of material porosity on re‐ignition is investigated. A surrogate ceramic material is used so as to separate the pyrolysis and combustion processes from those associated with heat transfer. Experimental data are reported for different sample thickness and porosity, and varying heat flux and water application time. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
993.
Ivnik Robert J.; Smith Glenn E.; Malec James F.; Petersen Ronald C.; Tangalos Eric G. 《Canadian Metallurgical Quarterly》1995,7(2):155
This project studied the intercorrelations and long-term stabilities of standard Wechsler Adult Intelligence Scale—Revised (WAIS—R), Wechsler Memory Scale—Revised (WMS—R), and Auditory–Verbal Learning Test (AVLT) summary indexes. It also reports similar data on the recently published Mayo Cognitive Factor Scales (MCFS), which are derivative indexes for the combined administrations of these 3 tests. These analyses challenge 2 assumptions that most psychologists make when interpreting adult cognitive tests: (a) that for cognitively normal people, performance in one cognitive domain correlates well with and predicts functioning in other cognitive domains, and (b) that in the absence of pathology, cognition is stable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
The doping properties of selected impurities in Hg1-x Cdx Te have been determined. Primary emphasis is on elements from Groups IB and IIIA, expected to substitute on the metal sublattice,
and on elements from Groups VA and VIIA, expected to substitute on the Te sublattice. In addition, the behavior of some elements
from Group IV as well as behavior of Li has been determined. Impurities were introduced into Hg1-x Cdx Te either by diffusion or during crystal growth. Cu, Ag and Li are fast diffusing acceptors, Ga is a fast diffusing donor,
Al and Si are donors which require high diffusion temperature to effect diffusion, P and As are slowly diffusing acceptors
and Br is a slowly diffusing donor. Sn appears to be inactive. In general, impurities substituted on the metal sublattice
are rapid diffusers while those substituted on Te sites are slow diffueers.
Supported in part by the Air Force Materials Laboratory, WPAFB, Ohio. 相似文献
995.
In response to the article by R. B. Zajonc (see record 1987-02628-001) on the confluence model and prediction of national Scholastic Aptitude Test (SAT) scores, the present authors reestimate Zajonc's model using their estimates of proportion of high school seniors taking the SAT. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
High resolution multispectral scanner (MSS) imagery of Savannah River nontidal wetlands were analyzed to identify 1) useful spectral bands for discriminating among National Wetland Inventory classes, 2) where the classes cluster in n-dimensional feature space, and 3) what wetland classification accuracies can be expected. Spectral measurements in the green (0.55–0.60 μm), red (0.65–0.70 μm), and near-infrared wavelengths (0.70–0.79 μm and 0.92–1.10 μm) provided the most useful information. Emergent marsh (both persistent and nonpersistent), scrub-shrub, mixed deciduous swamp forest, and mixed deciduous upland forest were found to cluster in somewhat predictable regions of 2- and 3-dimensional feature space. The overall classification accuracy of the Steel Creek delta study area was 83% and was assessed by comparing the remote sensing derived thematic map with 1325 linear meters of transects sampled in situ. These results suggest that high resolution aircraft MSS data can provide detailed vegetation type information for mapping both thermally affected and rejuvenating nontidal wetland in the South Carolina Savannah River Swamp System. 相似文献
997.
Eric Graham 《Computer Physics Communications》1976,12(1):121-124
This paper reviews work on stellar convection theory with a particular emphasis on numerical simulations of convection. The Boussinesq and the anelastic approximations of the fluid equations are introduced and solutions of the linearized equations for the onset of convection are described. Non-linear numerical solutions to the Boussinesq equations are discussed. Next, the character of stellar convection is considered. Convection is found to be intimately linked with a number of proceses in the stellar interior. Studies of stellar convection have either attempted to model a star with a very simplified treatment of convection or to solve the fluid equations for a range of parameters less extreme than those found in stars. Finally, a brief review is given of some of the numerical methods that have been employed. 相似文献
998.
The importance of surface contamination as a potential source of exposure to hazardous materials is discussed. Data from the literature concerning the resuspension of indoor surface contamination are presented. Reported procedures for quantitating surface contamination are compared. It is suggested that, despite its limitations, surface contamination monitoring may be useful in estimating potential risks from hazardous materials. 相似文献
999.
We report the fabrication and testing of 4-, 7-and 19-fibre fused biconical taper transmissive star couplers for use with single multimode fibres. Overall insertion losses on six couplers range from ?1.3 dB to ?2.6 dB. Losses are nearly independent of N, the number of fibres, but dispersion of the powers in the output fibres increases significantly with N. 相似文献
1000.
Daniel F. Varnell Eric J. Moskala Paul C. Painter Michael M. Coleman 《Polymer Engineering and Science》1983,23(12):658-662
FT-IR spectroscopic studies have been performed in an attempt to elucidate the nature of the specific interactions occurring in miscible poly(?-caprolactone) (PCL)-poly (vinyl chloride) (PVC) blends. Studies of low molecular weight analogues, polymer/solvent mixtures and blends of PCL and α-deuterated PVC are presented. The results strongly suggest that a hydrogen bonding type of interaction between the carbonyl bond of PCL and the α-hydrogen of PVC exists in compatible PCL-PVC blends. 相似文献