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1.
Many models of spoken word recognition posit the existence of lexical and sublexical representations, with excitatory and inhibitory mechanisms used to affect the activation levels of such representations. Bottom-up evidence provides excitatory input, and inhibition from phonetically similar representations leads to lexical competition. In such a system, long words should produce stronger lexical activation than short words, for 2 reasons: Long words provide more bottom-up evidence than short words, and short words are subject to greater inhibition due to the existence of more similar words. Four experiments provide evidence for this view. In addition, reaction-time-based partitioning of the data shows that long words generate greater activation that is available both earlier and for a longer time than is the case for short words. As a result, lexical influences on phoneme identification are extremely robust for long words but are quite fragile and condition-dependent for short words. Models of word recognition must consider words of all lengths to capture the true dynamics of lexical activation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The activation of safety valves causes the development of flow reaction forces that have to be transferred in an adequate way via the piping to the steel structure or via the connected vessel into the foundation. If the safety valve outlet piping is connected to a blowdown system or, in case of blowing off into the atmosphere, are equipped with a T‐piece at the outlet, the stationary reaction forces are compensated completely. The transient opening process, however, develops flow reaction forces which culminate in peaks of short duration. In this article, a simple method will be proposed for the estimation of the resulting reaction forces as a function of the length of the pipe at the safety valve outlet. CFD calculations and blowdown tests executed with a full‐lift safety valve have confirmed this method on principle. Special importance is attributed to the short duration of the effect of the reaction forces which seems to have only a negligible impact on the supporting steel structure.  相似文献   
3.
泌阳凹陷北部斜坡复杂断块群油田以断鼻、断块及断层+岩性油气藏为主,垂向含油层系多,平面上叠合连片,油气主要富集在鼻状构造主体部位的断鼻断块内。通过对研究区油气控制因素的分析,指出继承性的鼻状构造控制了油气聚集方向和富集程度,油气藏含油范围和油气藏高度则主要受断层封闭性和封闭程度的控制,油气分布规律受伸展构造所伴生的各种断块群构造型式的控制。  相似文献   
4.
基于高速分散的烟火药剂制备工艺   总被引:1,自引:1,他引:0  
探索高速分散的烟火药剂制备工艺,分析了高速分散制备工艺中的安全性。在实际应用中,此种工艺所制备的烟火药剂有燃烧精度高的优点。  相似文献   
5.
掺气减蚀保护作用的新概念   总被引:8,自引:0,他引:8  
利用针式掺气流速仪测量原型和模型掺气浓度场、流速场,气泡尺寸及其概率分布的研究成果表明,原型水流韦伯数高,形成微小气泡的能力比模型强,气泡上浮慢,接近底部的小尺寸气泡概率及掺气浓度比模型大。初步研究认为:0.2mm或0.5mm以下的微小气泡在掺气减蚀中起着主要作用,可能只要很小掺气浓度即可达到掺气减蚀的效果。因此以小尺寸气泡的掺气浓度,作为判断掺气减蚀保护作用的指标将更为准确。  相似文献   
6.
Analysis of non-stationary electrochemical oscillations emerges utilization of the techniques allowing an observation of time evolution of their parameters such as instantaneous frequency, amplitude or frequency band. An algorithm of extraction of these parameters can be based on one of linear or quadratic time-frequency representations of oscillations record. In this paper, the authors present representatives of such transformations (Choi-Williams and Cone-shaped) originating from one of the most popular joint time-frequency energy distribution—Wigner-Ville distribution. Short introduction to the mathematics of the topic discussed is provided, then the authors present an example of application in the analysis of current oscillations of copper dissolution process.  相似文献   
7.
In this work it is presented a study on the residence time distribution (RTD) of particles in a co-current pilot-plant spray dryer operated with a rotary atomization system. A nuclear technique is applied to investigate the RTD responses of spray dryers. The methodology is based on the injection of a radioisotope tracer in the feed stream followed by the monitoring of its concentration at the outlet stream. The experiments were performed during the drying of aqueous suspensions of gadolinium oxide. The RTD responses obtained experimentally presented good reproducibility, indicating that the technique applied is well suited to investigating fluid-dynamics of spray dryers. In addition to the experimental investigation, a mathematical model was used to describe the RTD experimental curves.  相似文献   
8.
This article deals with the kinetics of two-step anionic polymerization by way of a non-steady state method. Several molecular parameters can be evaluated using the formulae developed. A bimodal molecular weight distribution function for the resulting polymer is derived from the set of kinetic differential equations, which is in agreement with the experimental data reported.  相似文献   
9.
本文运用一典型的人工神经网络模型─“反向传播”模型,对高氧化态(Ⅱ─Ⅳ)三核金属簇合物的构型分布进行了分析,得到了较好的分类、预报结果为化合物结构分析提供了新的工具。  相似文献   
10.
从测得的竞聚率计算了单体链节在聚[苯乙烯-甲基丙烯酸β(甲基亚硫酰基)乙酯](PSM)中的序列分布。苯乙烯(S)或甲基丙烯酸β(甲基亚硫酰基)乙酯(M)的长序列的概率随着PSM中相应单体含量的增加而增加。对于S和M摩尔分数大致相等的PSM,单体链节的长序列分布函数值相接近。用与此结构相近的PSM合成的稀土金属络合物,其催化活性不佳。在M短序列分布和S长序列分布较高的情况下,络合物的催化活性最好。所得聚丁二烯的微观结构与PSM中单体单元的分布无关。  相似文献   
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