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11.
基于SDL的通信软件维护模型SMM 总被引:1,自引:0,他引:1
软件维护是软件生存周期的一个重要且花费很大的阶段,维护工作的自动化是软件行业十分迫切的需要。本文提出了一个基于ITU-TSDL语言的通信软件维护模型SMM。在此模型中,软件维护被分成三个部分:建立面向维护的数据库,制定维护规范和基于功能转换的自动维护。该模型将有助于软件维护支撑环境的建立 相似文献
12.
树文法是一种高维文法,能够用来表达二维以上复杂对象的构造规则.在模式识别、图式语言等领域有着广泛的应用前景.本文在树文法有关概念基础上提出了标志树、连接标志、标志树文法等概念,构造了标志树的匹配和识别算法,并成功解决了标志树文法的语法分析器构造问题. 相似文献
13.
汽车自动传动液的研制 总被引:2,自引:0,他引:2
介绍了自动传统液的分类规格、自动传动液的特性和相关的评定方法;研制了无锌和低锌配方的两种产品,经评定试验和实机使用,符合DexronⅡD、Mercon和AllisonC-4的规格要求,达到了国外同类产品的质量水平。 相似文献
14.
Due to the unique requirements of a series of projects to specify communications architectures using graphical representations (Cara and MFD), we have developed the communications-oriented rule-based language Carla (Cara Rule Language), which provides an executable specification of the architecture being developed. Carla is designed to provide the ability to specify and simulate high-level, possibly incomplete, specifications of communications architectures, and to allow the developer to refine the specification through the addition of behavior-describing rules. Carla is also well-suited to creating black-box specifications of any system whose behavior depends on input/output history. We describe the features of the language, discuss various design issues, and provide examples of various communications protocols specified in Carla. 相似文献
15.
16.
We describe a formal language/notation for DNA molecules that may contain nicks and gaps. The elements of the language, DNA
expressions, denote formal DNA molecules. Different DNA expressions may denote the same formal DNA molecule. We analyse the
shortest DNA expressions denoting a given formal DNA molecule. We determine lower bounds on their lengths and explain how
we construct these minimal DNA expressions. 相似文献
17.
论述了初春施工这个特定的施工季节所具有的特征,从气候、施工人员、工程情况及受冻土体等方面对初春施工易出现的问题进行了分析,对施工过程及施工技术规律性问题做了细化性研究和探讨。 相似文献
18.
根据Requisition的词义和询价、招标、订购文件的意义,建议将不能准确表达意思的中文译词“请购”改成“询购”。 相似文献
19.
This paper reports how the study of formal logical reasoning provides insight into more everyday types of reasoning, such as that involved in language comprehension. Both of these types of cognition are thought to involve the use of mental models, and so it is reasonable to think that the cognitive operations needed for formal logical reasoning would be involved in everyday reasoning as well. We focused on three aspects of formal reasoning: (a) the integration of information into a common mental model, (b) the drawing of inferences, and (c) the coordination of alternative possibilities. We were able to show that the integration and inference components were related to narrative comprehension processes, but the coordination of alternative models was not. Thus, there is evidence for some overlap in the mental processes used in formal and everyday reasoning. This further justifies the study of formal logical reasoning as a window into certain types of everyday reasoning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
Docherty Nancy M.; Cohen Alex S.; Nienow Tasha M.; Dinzeo Thomas J.; Dangelmaier Ruth E. 《Canadian Metallurgical Quarterly》2003,112(3):469
This study examined the degree to which different types of communication disturbances in the speech of 48 schizophrenia patients and 28 controls were variable and state related versus stable and traitlike. Clinically rated formal thought disorder and 5 types of referential disturbance showed substantial stability within participants over time. The sixth type of referential disturbance, the vague reference, was not stable over time. Formal thought disorder was associated with the severity of core psychotic symptoms in patients, whereas referential disturbances showed little or no association with positive or negative symptom severity. Furthermore, changes in psychotic symptoms over time were accompanied by corresponding changes in formal thought disorder but not referential disturbances. These results support the idea that some types of referential disturbances are traitlike and may be reflective of vulnerability as well as manifest illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献