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51.
Reviews the book, Basic Processes in Reading Visual Word Recognition by Derek Besner and Glyn W. Humphreys (see record 1990-99017-000). While there has been an increase in the amount of work on many different aspects of reading, as Besner and Humphreys point out in the overview to their book, the vast majority of the research on the topic of reading in the past twenty years has been concerned with the processes involved in word recognition. For this reason, Besner and Humphreys have attempted to bring together studies on topics which are both relevant to current debates in the field of word recognition, and which are likely to be important for future developments in the field. They have compiled an edited volume consisting of their overview and eight additional chapters. The editors have attempted to span the continuum of processes involved in word recognition and thus have included chapters which cover topics ranging from the visual analysis of words, to those on the influence of semantic factors on word recognition. The authors of these chapters comprise an impressive list of researchers in the field of word recognition, with the majority of chapters being authored by leading researchers on the topic. Given the stature of the authors and the range of topics covered, in theory this volume should provide a very thorough overview of current theory and research on reading. There is no question that each of the chapters is interesting and important in its own right. However, in practice the volume as a whole fell somewhat short of my expectations. The different tacts taken by different authors has resulted in a very uneven coverage of the current debates in the field. Notwithstanding these criticisms, I am sure that the majority of researchers in this field will consider this volume to be an important contribution. The book would provide a very useful addition to graduate courses in cognitive sciences and as a supplemental text for an undergraduate course on the psychology of reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
以单片机8031 为核心组成的采集、保护和通信模块,通过RS485 的连接,与486 工控微机构成了分布式35 kV 变电站的自控系统,实现变电站的计量、保护和控制等功能,以达到变电站的无人值守或少人值守。  相似文献   
53.
Algebraic properties of cryptosystem PGM   总被引:2,自引:0,他引:2  
In the late 1970s Magliveras invented a private-key cryptographic system calledPermutation Group Mappings (PGM). PGM is based on the prolific existence of certain kinds of factorization sets, calledlogarithmic signatures, for finite permutation groups. PGM is an endomorphic system with message space ℤ|G| for a given finite permutation groupG. In this paper we prove several algebraic properties of PGM. We show that the set of PGM transformations ℐ G is not closed under functional composition and hence not a group. This set is 2-transitive on ℤ|G| if the underlying groupG is not hamiltonian and not abelian. Moreover, if the order ofG is not a power of 2, then the set of transformations contains an odd permutation. An important consequence of these results is that the group generated by the set of transformations is nearly always the symmetric group ℒ|G|. Thus, allowing multiple encryption, any permutation of the message space is attainable. This property is one of the strongest security conditions that can be offered by a private-key encryption system. S. S. Magliveras was supported in part by NSF/NSA Grant Number MDA904-82-H0001, by U.S. West Communications, and by the Center for Communication and Information Science of the University of Nebraska.  相似文献   
54.
董竟 《包钢科技》2003,29(2):93-94
本文主要介绍了科技术语中的主要构词方法合成法所构成词语的结构和语义。  相似文献   
55.
基于浙江省优质水资源相对短缺的现实,提出了开展水库(群)优化调度的基本思路,在分析水库群不同联结方式特点的基础上,提出水库群联合优化调度的技术方法,实例验证表明,该方法增加供水量12%,科学可行。  相似文献   
56.
为解决文南油田高油气比井泵效低的问题,引进了二级采油技术。该技术采用特殊的二级采油工具,充分利用油井高油气比的特点,从而达到提高泵效的目的。文南油田30口井的现场试验表明,该技术应用后,平均单井泵效提高6%以上,平均单井视动液面下降739m,累积增油7560t。  相似文献   
57.
Thermogravimetry and pyrolysis in combination with gas chromatography and infrared spectroscopy were the experimental techniques applied to the thermal degradation of cinnamoylated poly(vinyl alcohol) samples, constituted from vinyl alcohol-vinyl cinnamate photocrosslinkable copolymers. The thermal decomposition products include gases, liquids and solids. The gases are formed from saturated and unsaturated volatile hydrocarbons C1? C4, carbon monoxide and carbon dioxide. The liquid fraction includes aromatic hydrocarbons and some oxygenated organic compounds. The solid product identified in the greatest amount was cinnamic acid. The content in the thermal decomposition products varies considerably both with copolymer composition and temperature.  相似文献   
58.
青坨子凸起馆陶组地震相研究   总被引:6,自引:0,他引:6  
青坨子凸起馆陶组是东辛油田潜在的油气勘探区带,但目前对本区的地层分布和沉积相特征尚未进行系统研究,区内钻井不多且钻井取心、录井资料较少,因此开展区域的沉积相研究必须依靠现有的三维地震资料。通过对青坨子凸起周缘馆陶组地震相的研究,总结了该区的沉积模式,这对于下一步的油气勘探有一定的指导意义。另外,本区河流地震相的研究工作也可以作为其他地区地震相研究的借鉴。  相似文献   
59.
A new concept, the generalized inverse group (GIG) of signal, is firstly proposed and its properties, leaking coefficients and implementation with neural networks are presented. Theoretical analysis and computational simulation have shown that (1) there is a group of finite length of generalized inverse signals for any given finite signal, which forms the GIG; (2) each inverse group has different leaking coefficients, thus different abnormal states; (3) each GIG can be implemented by a grouped and improved single-layer perceptron which appears with fast convergence. When used in deconvolution, the proposed GIG can form a new parallel finite length of filtering deconvolution method. On off-line processing, the computational time is reduced to O(N) from O(N2). And the less the leaking coefficient is, the more reliable the deconvolution will be.  相似文献   
60.
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