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961.
In this paper, we present a formalism called feature grammar and its application to several problems of semantic analysis. Our extension concerns the structure of the feature value sets, which can be complex, and the definition of unification, which is dependent on this structure. Moreover, we introduce generation rules for feature symbols in order to determine well-formed symbols, which form the alphabet of a formal language for natural language analysis.  相似文献   
962.
We prove that there exists no algorithm to decide whether the language generated by a context-free grammar is dense with respect to the lexicographic ordering. As a corollary to this result, we show that it is undecidable whether the lexicographic orderings of the languages generated by two context-free grammars have the same order type.  相似文献   
963.
介绍了研制开发“科研人员管理系统”应用软件的设想思想、软件构成、主要功能、特点及用FOXPRO语言实现该MIS系统时所使用的各种技术。  相似文献   
964.
罗素从研究意义指称论出发,对语句结构进行深入的逻辑分析,提出了著名的摹状词理论。这不仅成功地解决了哲学史上的语义学三大难题,而且对逻辑学和哲学都产生了巨大影响。本文仅就这一理论产生的理论渊源、三大语义学难题、理论内容及其对三大难题的解决进行概述,同时指出了该理论的重要意义。  相似文献   
965.
The efficient design of computation intensive multidimensional signal processing applications requires dealing with three kinds of constraints: those implied by the data dependencies, the non-functional requirements (real-time, power consumption) and resources availability of the execution platform. Modeling and Analysis of Real-time and Embedded systems (MARTE) UML profile through its repetitive structure modeling (RSM) package is well suited to model the inherent parallelism within these applications, a compact representation of parallel execution platforms and the distributive mapping of one on another. The execution of such a specification respects the whole set of constraints defined upon, while the quality of the scheduling is directly linked to the quality of the mapping of the multidimensional structures (data arrays or parallel loop nests) into time and space. We propose here a strategy to use a refactoring tool dedicated to this kind of application that allows to find good trade-offs in the usage of storage and computation resources and in parallelism (both task and data parallelism) exploitation. This strategy is illustrated on an industrial radar application.  相似文献   
966.
语言和文化间密不可分,无论是在文化差别还是在文化融合方面,它起着举足轻重的作用。文化是人类长期发展的结果,不同的文化有其不同的特点,文化差异的存在是必然的。语言教学同样存在差异。本文主要从地理环境因素来阐述文化差别这一问题。  相似文献   
967.
Age-normed tests of listening comprehension, oral expression, reading comprehension, and written expression were administered in Grades 1 (n = 128), 3, and 5, or 3 (n = 113), 5, and 7. Confirmatory factor analyses compared 1- and 4-factor models at each grade level and supported a 4-factor model of language by ear, mouth, eye, and hand. Multiple regressions identified which of the 3 other language skills explained unique variance in each of the 4 language skill outcomes and provided additional evidence that language is not a single skill. Individuals' ipsative scores (amount that the standard score for age on each language measure deviated from individual's mean for all 4 measures) showed that 25% to 30% of individuals showed relative strengths or weaknesses (±1 SD) in specific language skills, but only 7% were stable across Grades 3 and 5. Findings are discussed in reference to (a) theoretical implications for idea comprehension and expression via language by ear, mouth, eye, and hand; and (b) educational applications of observed developmental and individual differences for general, special, and gifted education. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
968.
The various uses of computer-mediated communication (CMC) are transforming the nature of social interactions and human relations among adolescents. Little is known about engagement of exceptional youth with this technology. The present study investigated the implications of language and social factors for frequency of CMC use and its relationship to adolescent well-being in young people with and without a history of specific language impairment (SLI). Eighty six adolescents with a history of SLI and 90 typically developing 17 year olds participated. Participants completed standardized assessments of psycholinguistic abilities and self-report measures of language motivations and social motivations for CMC use, as well as anxiety and depression. Results indicate that language abilities have a complex relationship with frequency of CMC use; social abilities have a more direct association and are predictive of frequency of CMC use. Both adolescents with SLI and typically developing adolescents were less shy online. No association was obtained between frequency of CMC use and reported emotional symptoms of anxiety and/or depression. It is argued that the characteristics of CMC, in terms of its less stringent language demands and its reduced-cues environment, can provide a medium for positive adaptation of adolescents with communication challenges.  相似文献   
969.
本文通过对福清文化会议中心和华侨博物馆的方案设计的概括和分析,阐述如何利用现代建筑语言在公共建筑设计上表达复杂的人文精神。  相似文献   
970.
Language is intimately connected with most aspects of human development. Because of this pervasive quality, language is incorporated as part of the individual's coping mechanisms, and at times it may even serve a definite defensive role. This investigation examines research and clinical data regarding the language independence phenomenon as it relates to the treatment of bilingual patients. Attempts are made to describe the way the bilingual individuals mobilize (shift) their languages under anxiety-producing conditions and how this shifting of languages can be utilized by these individuals as part of their coping mechanisms. There can be both positive and negative implications for treatment. In this regard, the article illustrates how the linguistic shifting may further reinforce defenses such as intellectualization, splitting, and isolation of affect. Linguistic shifting can also be technically introduced by monolingual clinicians to advance the therapeutic process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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