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71.
In 5 experiments, the authors tested whether the processing of nonconscious spatial stimulus information depends on a prior intention. This test was conducted with the metacontrast dissociation paradigm. Experiment 1 demonstrated that masked primes that could not be discriminated above chance level affected responses to the visible stimuli that masked them. Experiments 2 and 3 showed that this effect was abolished when the task instruction was changed in such a way that the primes ceased to be task relevant. Experiments 4 and 5 demonstrated that a prime's effect depended on whether it was associated with the same response as the target or with an opposite response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Estimation and hypothesis testing based on normal samples censored in the middle are developed and shown to be remarkably
efficient and robust to symmetric shorttailed distributions and to inliers in a sample. This negates the perception that sample
mean and variance are the best robust estimators in such situations (Tiku, 1980; Dunnett, 1982).
Professor Emeritus, Department of Mathematics and Statistics, McMaster University,
Professor Emeritus, Department of Mathematics and Statistics, McMaster University, 相似文献
73.
实时分布式系统中,如果结点n自从上一次收到结点i的广播信息后经过超时值时没有再收到结点i的广播信息,就认为结点i失败。这时需要调整各正常结点的优先列表,以保证每个结点被一个也只能是一个结点选择为自己的第后个优先结点,以减少任务的失败率。本文提出了一种确定最佳超时值以及检测结点失败并且调整结点的优先列表以处理结点失败的新方法。 相似文献
74.
本文讨论逆绎推理的形式化问题,指出这一问题的认知基础,然后证明逆绎推理可通过建立必要性假设来完成;NH构成了对已有知识订的扩充,必须构造必要性假设理论来捕捉逆绎推理的逻辑特征,本文选择缺席逻辑作为形式化NL的理论框架,并指出NL的基本性质。 相似文献
75.
考察研究了9种预处理体系对8种常见金属氰络合物的离解效率,结果表明:有6种预处理体系均能得到较满意的结果。此外,还探讨了预处理体系中金属氰络合物的离解机理,提出了各种存在形式氰化物离解的可能机理。 相似文献
76.
Process capability index Cpk has been widely used in the manufacturing industry as a process performance measure. In this paper, we investigate the natural estimator of the index Cpk, and show that under the assumption of normality its distribution can be expressed as a mixture of the chi-square and the normal distributions. We also implement the theory of hypothesis testing using the natural estimator of Cpk, and provide efficient Maple programs to calculate the p-values as well as the critical values for various values of -risk, capability requirements, and sample sizes. The behavior of the p-values and critical values as functions of the distribution parameters are investigated to obtain tight critical values for reliable testing. Based on the test, we develop a simple and practical procedure for in-plant applications. The practitioners can use the proposed procedure to determine whether their process meets the preset capability requirement, and make reliable decisions. 相似文献
77.
The octave illusion (D. Deutsch, 1974) occurs when 2 tones separated by an octave are alternated repeatedly, such that when the right ear receives the high tone, the left ear receives the low tone, and vice versa. Most subjects in the original study reported hearing a single tone that alternated from ear to ear, whose pitch also alternated from octave to octave, and D. Deutsch (1975a) proposed an explanation in terms of separate what and where auditory pathways. C. D. Chambers, J. B. Mattingley, and S. A. Moss (2002) argued that the perceived pitch difference generally corresponds more to a semitone and proposed an alternative explanation in terms of diplacusis. This article argues that Chambers et al. used problematic procedures and reports a new experiment on the octave illusion. The findings confirm that an octave difference is generally perceived, and they agree with the model of Deutsch (1975a) but are at variance with the diplacusis hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Processing capacity-defined as the relative ability to perform mental work in a unit of time-is a critical construct in cognitive psychology and is central to theories of visual attention. The unambiguous use of the construct, experimentally and theoretically, has been hindered by both conceptual confusions and the use of measures that are at best only coarsely mapped to the construct. However, more than 25 years ago, J. T. Townsend and F. G. Ashby (1978) suggested that the hazard function on the response time (RT) distribution offered a number of conceptual advantages as a measure of capacity. The present study suggests that a set of statistical techniques, well-known outside the cognitive and perceptual literatures, offers the ability to perform hypothesis tests on RT-distribution hazard functions. These techniques are introduced, and their use is illustrated in application to data from the contingent attentional capture paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
James D. Johnston Ashlin E. Cowger Robert J. Graul Ryan Nash Josie A. Tueller Nathan R. Hendrickson Daniel R. Robinson John D. Beard K. Scott Weber 《Indoor air》2019,29(6):1005-1017
Recent work suggests that evaporative coolers increase the level and diversity of bioaerosols, but this association remains understudied in low‐income homes. We conducted a cross‐sectional study of metropolitan, low‐income homes in Utah with evaporative coolers (n = 20) and central air conditioners (n = 28). Dust samples (N = 147) were collected from four locations in each home and analyzed for dust‐mite allergens Der p1 and Der f1, endotoxins, and β‐(1 → 3)‐d ‐glucans. In all sample locations combined, Der p1 or Der f1 was significantly higher in evaporative cooler versus central air conditioning homes (OR = 2.29, 95% CI = 1.05‐4.98). Endotoxin concentration was significantly higher in evaporative cooler versus central air conditioning homes in furniture (geometric mean (GM) = 8.05 vs 2.85 EU/mg, P < .01) and all samples combined (GM = 3.60 vs 1.29 EU/mg, P = .03). β‐(1 → 3)‐d ‐glucan concentration and surface loads were significantly higher in evaporative cooler versus central air conditioning homes in all four sample locations and all samples combined (P < .01). Our study suggests that low‐income, evaporative cooled homes have higher levels of immunologically important bioaerosols than central air‐conditioned homes in dry climates, warranting studies on health implications and other exposed populations. 相似文献
80.
Marko Jovanovi? Richard Tyldesley-Worster Gottfried Pohlentz Jasna Peter-Katalini? 《International journal of molecular sciences》2014,15(4):6527-6543
Human milk oligosaccharides (HMO) represent the bioactive components of human milk, influencing the infant’s gastrointestinal microflora and immune system. Structurally, they represent a highly complex class of analyte, where the main core oligosaccharide structures are built from galactose and N-acetylglucosamine, linked by 1–3 or 1–4 glycosidic linkages and potentially modified with fucose and sialic acid residues. The core structures can be linear or branched. Additional structural complexity in samples can be induced by endogenous exoglycosidase activity or chemical procedures during the sample preparation. Here, we show that using matrix-assisted laser desorption/ionization (MALDI) quadrupole-time-of-flight (Q-TOF) collision-induced dissociation (CID) as a fast screening method, diagnostic structural information about single oligosaccharide components present in a complex mixture can be obtained. According to sequencing data on 14 out of 22 parent ions detected in a single high molecular weight oligosaccharide chromatographic fraction, 20 different oligosaccharide structure types, corresponding to over 30 isomeric oligosaccharide structures and over 100 possible HMO isomers when biosynthetic linkage variations were taken into account, were postulated. For MS/MS data analysis, we used the de novo sequencing approach using diagnostic ion analysis on reduced oligosaccharides by following known biosynthetic rules. Using this approach, de novo characterization has been achieved also for the structures, which could not have been predicted. 相似文献