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991.
An approximate method is proposed for taking account of stochastic dependences between failures of elements when monitoring an index of the probability type. The method is based on transforming the vector of the duration of failure-free operation of the elements having stochastically dependent components into a vector with independent components. It may be used in order to plan independent tests of the elements when confirming the requirements imposed on systems and on the processing of their data. 相似文献
992.
G. Lukatela and M. T. Turvey (1994x) showed that at a 57-ms prime-presentation duration, the naming of a visually presented target word (frog) is primed not only by an associate word (toad) but also by a homophone (towed) and a pseudohomophone (tode) of the associate. At a 250-ms prime presentation, priming with the homophone was no longer observed. In Experiment 1, the authors replicated these priming effects in the Dutch language. Next, the authors extended the priming paradigm to a word/legalnon-word lexical decision task (Experiments 2 and 3) and a word/pseudohomophone decision task (Experiment 4). Phonologically mediated associative priming was observed in all conditions with pseudohomophonic primes but not with homophonic primes. The latter did not prime at a 250-ms prime-presentation time and at 57 ms in the word/pseudohomophone task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
分析全国及 9大流域片 1997~ 2 0 0 0年逐年降水量、天然径流量的变化趋势及降水量年内变化情况 ,研究近期我国地表水资源变化趋势及近年旱涝特点 .研究表明 :自 1997年以来 ,我国降水量除 1998年比多年平均值偏多 11.6 % ,长江、嫩江等河流发生了特大洪水 ,是丰水年外 ,其余的1997,1999,2 0 0 0年 3年均比多年平均值偏少 0 .9%~ 4 % ,属平水年 ,为南丰北枯型 相似文献
994.
Numerous definitions of droughts which are based on different climatological time series have been in use. In this paper, the development of drought indicators by using different time series is described. These drought indicators were developed for use by the Department of Natural Resources in the State of Indiana, U.S.A. The second part of the study deals with an analysis of the consistency of results obtained by using different time series, in order to select two or three of the commonly available series for drought analysis. Past drought data are used to test the performance of the drought indicators. As a result of this study, three month precipitation, monthly river flow and the Palmer Hydrologic Drought Index series are recommended for operational use. 相似文献
995.
K. Rayner, A. Pollatsek, D. Drieghe, T. J. Slattery, and E. D. Reichle (see record 2007-11669-010) argued that the R. Kliegl, A. Nuthmann, and R. Engbert (see record 2006-01956-002) corpus-analytic evidence for distributed processing during reading should not be accepted because (a) there might be problems of multicollinearity, (b) the distinction between content and function words and the skipping status of neighboring words was ignored, and (c) there are inconsistencies with experimental results. Reanalyses with linear mixed-effect models demonstrate that (a) regression coefficients are stable across 9 samples, (b) lexical status and skipping status (and their interactions) are highly significant but do not account for the effects of word frequency for content and for function words, and (c) there is strong evidence for lexical processing of content words while fixating function words to the left of them. A critical result about fixation durations prior to skipped words is replicated in an experiment. The distinction between correlational analyses and well-controlled experiments and questions about generalizability of results are discussed. The author argues for a complementary role of corpus analysis, computational modeling, and experiments in reading research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Patton Brianne C.; Hook Michelle A.; Ferguson Adam R.; Crown Eric D.; Grau James W. 《Canadian Metallurgical Quarterly》2004,118(3):653
Spinalized rats that receive shock when 1 hind limb is extended (contingent shock) exhibit an increase in flexion duration, a simple form of instrumental learning. Rats that receive shock independent of leg position (noncontingent shock) do not exhibit an increase in flexion duration and fail to learn when tested with contingent shock 24 hr later. It appears that noncontingent shock induces an intraspinal modification that inhibits the capacity to learn. The authors propose that the mechanisms that underlie this effect depend on de novo protein synthesis. To evaluate this hypothesis, the authors gave spinalized rats the protein synthesis inhibitor Cycloheximide (CXM) or saline intrathecally prior to, or immediately after, noncontingent shock exposure. Twenty-four hours later, rats were tested with contingent shock. Rats that received the vehicle and noncontingent shock failed to learn. CXM-treated shocked rats learned normally, suggesting that the learning deficit depends on protein synthesis within the spinal cord. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
998.
通过测量KClO_3-C-DDNP(A种)、KClO_3-C(B种)、KClO_3-Sb_2S_3-DDNP(C种)三种常用电引火药头的燃烧火焰模拟信号,比较它们的发火性能.结果表明,KClO_3-C-DDNP(A种)引火药头优于其它两种. 相似文献
999.
Kosnik William; Kline Donald; Fikre John; Sekular Robert 《Canadian Metallurgical Quarterly》1988,3(1):37
Reports an error in "Ocular fixation control as a function of age and exposure duration" by William Kosnik, Donald Kline, John Fikre and Robert Sekuler (Psychology and Aging, 1987[Sep], Vol 2[3], 302-305). In the aforementioned article, the following corrections should be made: 1. The title of Table 1 should be changed to Mean Bivariate Areas (min-arc2) and Mean Horizontal and Vertical Standard Deviations (min-arc) of Fixations of Older and Younger Groups. 2. The equation on page 304 should have used the natural log rather than the log base 10. The corrected equation is provided in the erratum. (The following abstract of the original article appeared in record 1988-01066-001.) In previous work we reported that fixation stability did not deteriorate in older adults over relatively long viewing durations. In the present study we reanalyzed the data to examine potential aging effects on fixational control for viewing durations typically used in psychological experimentation. Monocular eye movements were recorded in 12 older and 12 younger observers using a dual Purkinje image technique, while observers fixated a stationary target. The two-dimensional scatter of eye positions was measured during nine viewing durations ranging from 100 ms to 12.8 s. Fixational control of the two groups was comparable at all of the viewing durations. Both younger and older observers were able to maintain fixation within an area several times smaller than the size of the fovea. Implications for aging studies that use briefly presented visual stimuli are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
K. J. Phillips 《Strain》1985,21(1):19-22
An insight into strain gauge telemetry techniques explaining why telemetry can offer interesting advantages over conventional strain gauge systems. The difference between a.c. strain gauge measurements and analogue to digital conversion followed by a.c. transmission is discussed together with the importance of a.c. transmission in the avoidance of drifts and parasitic effects applicable to d.c. systems.
A comparison between frequency modulation (FM) and time or pulse duration modulation (PDM) explains why PDM can offer significant advantages. 相似文献
A comparison between frequency modulation (FM) and time or pulse duration modulation (PDM) explains why PDM can offer significant advantages. 相似文献