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基于Language Model的地理信息检索模型(英文) 被引量:3
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作者 黎志升 王煦法 《中国科学技术大学学报》 CAS CSCD 北大核心 2010年第2期203-209,共7页
区别于传统的信息检索,地理信息检索通过一个查询范围词来限制用户的兴趣区域.目前的技术一般是把该查询范围词作为一个过滤器,将在该范围之外的文档排除在查询结果外.但是,词在地理空间的频率分布并不是均匀的,因此词在排序结果中的重... 区别于传统的信息检索,地理信息检索通过一个查询范围词来限制用户的兴趣区域.目前的技术一般是把该查询范围词作为一个过滤器,将在该范围之外的文档排除在查询结果外.但是,词在地理空间的频率分布并不是均匀的,因此词在排序结果中的重要性应该随着查询范围的变化而有所改变.为此,提出了一种新的基于语言模型的地理信息查询模型,把查询范围引入到传统的语言模型中.在该模型中,引入了一个local model来描述查询词的地理分布特性.实验结果表明,新的检索模型优于TF-IDF与传统的语言模型. 展开更多
关键词 语言模型 地理感知 地理 信息检索
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Vari-gram language model based on word clustering
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作者 袁里驰 《Journal of Central South University》 SCIE EI CAS 2012年第4期1057-1062,共6页
Category-based statistic language model is an important method to solve the problem of sparse data.But there are two bottlenecks:1) The problem of word clustering.It is hard to find a suitable clustering method with g... Category-based statistic language model is an important method to solve the problem of sparse data.But there are two bottlenecks:1) The problem of word clustering.It is hard to find a suitable clustering method with good performance and less computation.2) Class-based method always loses the prediction ability to adapt the text in different domains.In order to solve above problems,a definition of word similarity by utilizing mutual information was presented.Based on word similarity,the definition of word set similarity was given.Experiments show that word clustering algorithm based on similarity is better than conventional greedy clustering method in speed and performance,and the perplexity is reduced from 283 to 218.At the same time,an absolute weighted difference method was presented and was used to construct vari-gram language model which has good prediction ability.The perplexity of vari-gram model is reduced from 234.65 to 219.14 on Chinese corpora,and is reduced from 195.56 to 184.25 on English corpora compared with category-based model. 展开更多
关键词 word similarity word clustering statistical language model vari-gram language model
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Linguistic Reflection on the Online Catchword of Appreciation —From the Perspective of Usage-based Language Model and Complex Adaptive System Theory
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作者 HE Xiang 《北京第二外国语学院学报》 2016年第5期139-139,共1页
Language is a special social phenomenon and is always on the changing process with the development of society. During the evolving process of language, new language varieties will continuously emerge due to the change... Language is a special social phenomenon and is always on the changing process with the development of society. During the evolving process of language, new language varieties will continuously emerge due to the changes of some social and cultural factors. Cyber language is universally accepted as one type of the social language varieties. Basically, cyber language can be treated as a complex adaptive system which is influenced by the interaction between users’ cognition, social culture and the surrounding environments. Thus it is safe to say that cyber language is always undergoing a dynamic evolving process. With the usage-based language model as the theoretical foundation, this paper proposes a Complex Adaptive System (CAS) approach to analyze the expression of Appreciation to explore the complex, dynamic and nonlinear development of cyber language from the angle of meaning construction, grammaticalization and functional adaption respectively. It is found that the expression of Appreciation is experiencing adaptively a semantic connotations development and a process of grammatical functions expansion as well. This paper suggests that the emergence and development of cyber language is a novel and trendy social language phenomenon. Network language can achieve its process and evolution under the huge impact of social changes and social promotions. When faced with the changing surroundings, cyber language itself enjoys a timely adaption and responsive development to keep up with the new environments, which reflects the basic principle of language development, namely, language changes with the development of society. 展开更多
关键词 Usage-based language model Complex Adaptive System Theory the expression of APPRECIATION cyber language language var
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Studies on the Models of Children' s Foreign Language Education
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作者 Li Qingzhao 《学术界》 CSSCI 北大核心 2015年第7期302-309,共8页
There are hot arguments on foreign language learning "the sooner the better" and it is critical to children' s foreign language education policies.This study combs series of empirical studies and models ... There are hot arguments on foreign language learning "the sooner the better" and it is critical to children' s foreign language education policies.This study combs series of empirical studies and models to analyze disadvantages of the belief of foreign language education "the sooner the better" in China.The findings are:1.Age is not the key factor to foreign language achievement,learning strategies,language distance and mother language proficiency are important factors that can not be ignored;2.The results in external foreign language studies can not be used directly to guide domestic foreign language education policies,for practical demands must be taken in consideration. 展开更多
关键词 外语学习 教育模式 儿童 教育政策 序列分析 学习策略 距离和
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Language Interaction and the Influence of the Chinese Language
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作者 He Xiaoyong 《学术界》 CSSCI 北大核心 2015年第9期303-307,共5页
It is necessary that each era has its own value orientation of the language civilization,which forms the motivation,model and pragmatic hypothesis.As for the Chinese language,it is the Chinese philosophical semantics.... It is necessary that each era has its own value orientation of the language civilization,which forms the motivation,model and pragmatic hypothesis.As for the Chinese language,it is the Chinese philosophical semantics.Language and civilization integrate into each other,so when analyzing linguistics,we shall separate the lexeme on the basis of context.Pragmatics establishes the context for the Chinese language,the basis of which is boosting the education of the Chinese language.As result,pragmatics is not only a branch of linguistics but also the construction of popular linguistics.The Chinese language course is only the concrete implementation of pragmatics and the basic project for the language context in a popular and globalizational style. 展开更多
关键词 语言学 相互作用 汉语 中国哲学 语文教育 语用学 语义学 上下文
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"Chinese Character- Chinese Language" the Regional Linguistic System. Developing Process and Current Situation
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作者 Zhang Lu 《学术界》 CSSCI 北大核心 2015年第2期303-307,共5页
Linguistic civilization orientation is a necessity for all eras,with which the motivation,viable model and pragmatic hypothesis of the language can be formed."Chinese character— Chinese language"takes on di... Linguistic civilization orientation is a necessity for all eras,with which the motivation,viable model and pragmatic hypothesis of the language can be formed."Chinese character— Chinese language"takes on different cultures in different regions, embodying the integration of language and civilization. As a result, in order to analyze linguistics, it is necessary for us to compare the Chinese language at home and abroad, and it is the linguistic construction based on the public. The modern Chinese language inherits the cultural connotation of the Chinese linguistics and answers the regional hypothesis and establishes the new linguistic system for the Chinese language in different regions. 展开更多
关键词 语言系统 中国 语文 文化内涵 语言学 国内外 字符
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基于Modelica的发电湿汽轮机系统仿真及特性分析
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作者 王劲韬 曾国庆 +3 位作者 谢旭阳 谢罗涛 邹梓仪 陈国兵 《舰船科学技术》 北大核心 2025年第4期105-111,共7页
本文旨在解决船用发电湿汽轮机系统在使用传统模型和数字驱动方法时,数据完整性和动态仿真精度方面存在局限性的问题。在船用发电湿汽轮机物理试验平台的基础上,采用模块化建模方法,结合自顶向下的需求分析策略和自下而上的建模思想,明... 本文旨在解决船用发电湿汽轮机系统在使用传统模型和数字驱动方法时,数据完整性和动态仿真精度方面存在局限性的问题。在船用发电湿汽轮机物理试验平台的基础上,采用模块化建模方法,结合自顶向下的需求分析策略和自下而上的建模思想,明确模型的功能要求,并逐步完成各设备模块功能的调试和组合。分析结果显示,静态和变工况仿真结果的数据误差均低于5%,且在变工况下与实际机组情况基本一致。这些仿真结果能够较为真实地反映系统的运行状况,能够为后续船舶动力数字孪生系统的建立和虚实交互提供了基础。 展开更多
关键词 模块化建模 系统仿真 modelICA语言 船用发电湿汽轮机 MWorks仿真平台
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Intelligent modeling method for OV models in DoDAF2.0 based on knowledge graph
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作者 ZHANG Yue JIANG Jiang +3 位作者 YANG Kewei WANG Xingliang XU Chi LI Minghao 《Journal of Systems Engineering and Electronics》 2025年第1期139-154,共16页
Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a vi... Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a viewpoint in DoDAF2.0,the operational viewpoint(OV)describes operational activities,nodes,and resource flows.The OV models are important for SoS architecture development.However,as the SoS complexity increases,constructing OV models with traditional methods exposes shortcomings,such as inefficient data collection and low modeling standards.Therefore,we propose an intelligent modeling method for five OV models,including operational resource flow OV-2,organizational relationships OV-4,operational activity hierarchy OV-5a,operational activities model OV-5b,and operational activity sequences OV-6c.The main idea of the method is to extract OV architecture data from text and generate interoperable OV models.First,we construct the OV meta model based on the DoDAF2.0 meta model(DM2).Second,OV architecture named entities is recognized from text based on the bidirectional long short-term memory and conditional random field(BiLSTM-CRF)model.And OV architecture relationships are collected with relationship extraction rules.Finally,we define the generation rules for OV models and develop an OV modeling tool.We use unmanned surface vehicles(USV)swarm target defense SoS architecture as a case to verify the feasibility and effectiveness of the intelligent modeling method. 展开更多
关键词 system of systems(SoS)architecture operational viewpoint(OV)model meta model bidirectional long short-term memory and conditional random field(BiLSTM-CRF) model generation systems modeling language
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基于Modelica语言的复杂机械系统统一建模平台研究 被引量:18
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作者 吴义忠 吴民峰 陈立平 《中国机械工程》 EI CAS CSCD 北大核心 2006年第22期2391-2396,共6页
研究了基于Modelica语言的复杂机械系统统一建模平台MWorks的关键技术。在分析Modelica模型描述和Modelica标准库(MSL)结构的基础上,设计了基于Modelica语言的可视化建模系统框架,提出了基于有向无环图的MSL内存存储模式,提高了可视化... 研究了基于Modelica语言的复杂机械系统统一建模平台MWorks的关键技术。在分析Modelica模型描述和Modelica标准库(MSL)结构的基础上,设计了基于Modelica语言的可视化建模系统框架,提出了基于有向无环图的MSL内存存储模式,提高了可视化建模速度;提出了基于实体句子匹配的快速图文切换算法;设计了基于句子的线性二叉树结构,实现了文本和图形编辑环境相统一的恢复操作。最后给出了MWorks系统的建模实例。 展开更多
关键词 复杂机械系统 modelICA语言 可视化建模 有向图
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多领域建模语言Modelica类型解析研究与实现 被引量:5
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作者 吴民峰 吴义忠 +1 位作者 周凡利 陈立平 《计算机工程与应用》 CSCD 北大核心 2006年第25期80-83,共4页
类型解析是编译器开发的一项重要工作,也是语义分析的一个最重要组成部分。基于Modelica建模语言,研究了编译器类型系统的作用域、类型检查等关键技术,提出了类型系统的解析和查找机制,实现了类型检查及错误处理机制,并在多领域物理系... 类型解析是编译器开发的一项重要工作,也是语义分析的一个最重要组成部分。基于Modelica建模语言,研究了编译器类型系统的作用域、类型检查等关键技术,提出了类型系统的解析和查找机制,实现了类型检查及错误处理机制,并在多领域物理系统建模与仿真平台MWorks系统中得到应用。 展开更多
关键词 类型系统 modelICA 多领域 建模语言
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多体动力学模型的Modelica语言建模 被引量:3
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作者 刘俊 黄运保 +1 位作者 陈立平 王启富 《中国机械工程》 EI CAS CSCD 北大核心 2010年第9期1088-1093,共6页
对Adams多体模型结构及Modelica模型的转换方法进行了研究。对多体动力学模型结构及建模方式进行分析,根据Adams多体模型结构设计了对应的Modelica多体模型结构。研究了Adams多体模型各组件包含的信息,以及与Modelica模型的异同,提出了... 对Adams多体模型结构及Modelica模型的转换方法进行了研究。对多体动力学模型结构及建模方式进行分析,根据Adams多体模型结构设计了对应的Modelica多体模型结构。研究了Adams多体模型各组件包含的信息,以及与Modelica模型的异同,提出了各多体组件的转换方法。最后给出了多体模型转换验证实例与结果。该研究有助于提高多领域仿真系统的多体建模效率及与传统多体系统的兼容性。 展开更多
关键词 多领域统一建模 modelICA语言 多体动力学模型 模型转换
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基于仿真建模语言Modelica的多领域仿真实现 被引量:9
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作者 于涛 曾庆良 《山东科技大学学报(自然科学版)》 CAS 2005年第4期13-16,共4页
介绍了Modelica语言发展背景及特点,并对其语法结构进行了分析。介绍了Modelica模型库和Modelica仿真建模工具。最后,在仿真建模软件Dymola中,对一直流电机驱动系统进行了建模和仿真。仿真结果证明,Modelica语言及其模型库简单、易用,... 介绍了Modelica语言发展背景及特点,并对其语法结构进行了分析。介绍了Modelica模型库和Modelica仿真建模工具。最后,在仿真建模软件Dymola中,对一直流电机驱动系统进行了建模和仿真。仿真结果证明,Modelica语言及其模型库简单、易用,在多领域仿真建模中有很好的发展前景。 展开更多
关键词 多领域仿真 仿真建模语言 modelICA 面向对象
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基于Modelica语言建模的柴油机稳动态性能仿真与试验 被引量:2
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作者 李文辉 刘长铖 +2 位作者 马修真 夏文 张子鉴 《农业工程学报》 EI CAS CSCD 北大核心 2016年第21期87-94,共8页
针对传统柴油机建模效率不高、所建模型抽象不易理解、软件平台开放程度差、模型通用性低的问题,采用多领域统一物理建模规范Modelica语言和面向对象的建模思想建立了柴油机的仿真模型。以上柴D4114B型发电用柴油机为例,在解决上述问题... 针对传统柴油机建模效率不高、所建模型抽象不易理解、软件平台开放程度差、模型通用性低的问题,采用多领域统一物理建模规范Modelica语言和面向对象的建模思想建立了柴油机的仿真模型。以上柴D4114B型发电用柴油机为例,在解决上述问题的同时模拟了负荷特性下柴油机的稳态过程,最高压力、排温等稳态数据点的实测值与仿真值的最大相对误差为8.9%,证明了所建立的柴油机模型具有较好的稳态性能。在此基础上进行了动态仿真,模拟了转速、单缸循环油量等参数的动态变化规律,并将部分参数的仿真值与实测值进行比较,两者吻合得比较好,证明了所建立的柴油机模型能较好地预测其动态性能,可为后续的基于Modelica语言的柴油机建模提供参考。 展开更多
关键词 modelICA语言 柴油机 建模 仿真
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论MVC模式改进Model 2x模型 被引量:1
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作者 王鑫 孙小平 谭畅 《控制工程》 CSCD 2005年第5期480-481,485,共3页
研究了MVC(模块、视图、控制)模式的改进结构,该模式可以使业务逻辑与现实逻辑相分离,增强可维护性。以Java语言为基础探讨了使用Struts和XSLT相结合实现MVC,架构出具有良好的扩展性和伸缩性的基于Web的系统。介绍了Model1模型和Model2... 研究了MVC(模块、视图、控制)模式的改进结构,该模式可以使业务逻辑与现实逻辑相分离,增强可维护性。以Java语言为基础探讨了使用Struts和XSLT相结合实现MVC,架构出具有良好的扩展性和伸缩性的基于Web的系统。介绍了Model1模型和Model2模型以及每个模型的优缺点,由此论述MVC模式所衍生出来的Model2x模型。实际应用表明该方法有助于提高代码的可重用性和灵活性,通过将问题划分为更小的组件,当技术空间或问题空间中出现变化时会有更多的机会重用代码,在实际项目应用中效果良好。 展开更多
关键词 MVC模式 model 2x模型 Java和xml开发语言 WEB系统
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角色建模工具RModeler的设计与实现
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作者 文斌 毛晓光 《计算机应用研究》 CSCD 北大核心 2008年第4期1257-1260,共4页
提倡在对象技术中基于角色识别对象及其协调关系,然后展开到类模型、接口模型、实体模型,同时对角色模型的形式化定义和表示方法进行了系统地研究,并在此基础上设计和实现了基于RML的可视化角色建模工具RModeler。RModeler目前完成了代... 提倡在对象技术中基于角色识别对象及其协调关系,然后展开到类模型、接口模型、实体模型,同时对角色模型的形式化定义和表示方法进行了系统地研究,并在此基础上设计和实现了基于RML的可视化角色建模工具RModeler。RModeler目前完成了代码实现和测试工作,并在实际开发中使用,运行良好。RModeler支持业务过程中采用RML语言的建模,具备将RML模型转换为UML模型的功能,采用业界标准数据描述格式XMI来传递和共享建模信息。 展开更多
关键词 角色 角色模型 角色建模语言 软件工具 扩展元数据交换
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ChatModeler:基于大语言模型的人机协作迭代式需求获取和建模方法 被引量:13
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作者 靳东明 金芝 +1 位作者 陈小红 王春晖 《计算机研究与发展》 EI CSCD 北大核心 2024年第2期338-350,共13页
需求获取和建模是需求工程中的关键步骤,影响后续系统设计与实现.传统的需求获取和建模方法通常由需求提供者、需求分析师等多类干系人共同协作、反复迭代完成,需要耗费大量的人力.如何减轻需求提供者与需求分析师的负担、提高获取和建... 需求获取和建模是需求工程中的关键步骤,影响后续系统设计与实现.传统的需求获取和建模方法通常由需求提供者、需求分析师等多类干系人共同协作、反复迭代完成,需要耗费大量的人力.如何减轻需求提供者与需求分析师的负担、提高获取和建模的效率有着重要意义.现有工作中有的使用知识库来提供更多知识,以辅助获取或者建模,有的利用自然语言处理等技术对获取或者建模过程进行自动化,但是它们并没有减轻需求提供者的负担.利用大语言模型(large language models,LLMs)的生成能力,提供了一种人机协作的迭代式需求获取和建模框架ChatModeler.具体来说,根据真实世界中需求团队的分工及协作关系,将部分需求提供者、需求分析师等角色的工作由大语言模型承担,而需求提供者只需要进行确认.为大语言模型扮演的各种角色进行了提示词设计,该提示词会随需求的元模型而变化.ChatModeler在7个需求案例上与3种需求模型的自动建模方法进行了14组对比实验,证明了ChatModeler在降低需求提供者的负担和生成高质量需求模型2个方面上的优越性. 展开更多
关键词 需求工程 需求诱导 大语言模型 人机协作 提示工程
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Capability requirements modeling and verification based on fuzzy ontology 被引量:4
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作者 Qingchao Dong Zhixue Wang Weixing Zhu Hongyue He 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第1期78-87,共10页
The capability requirements of the command, control, communication, computing, intelligence, surveillance, reconnaissance (C41SR) systems are full of uncertain and vague information, which makes it difficult to mode... The capability requirements of the command, control, communication, computing, intelligence, surveillance, reconnaissance (C41SR) systems are full of uncertain and vague information, which makes it difficult to model the C41SR architecture. The paper presents an approach to modeling the capability requirements with the fuzzy unified modeling language (UML) and building domain ontologies with fuzzy description logic (DL). The UML modeling constructs are extended according to the meta model of Depart- ment of Defense Architecture Framework to improve their domain applicability, the fuzzy modeling mechanism is introduced to model the fuzzy efficiency features of capabilities, and the capability requirement models are converted into ontologies formalized in fuzzy DL so that the model consistency and reasonability can be checked with a DL reasoning system. Finally, a case study of C41SR capability requirements model checking is provided to demonstrate the availability and applicability of the method. 展开更多
关键词 fuzzy ontology fuzzy unified modeling language (UML) fuzzy description logic (DL) model checking.
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XML-based integration data model and schema mappingin multidatabase systems 被引量:5
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作者 LiRuixuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期437-444,共8页
Multidatabase systems are designed to achieve schema integration and data interoperation among distributed and heterogeneous database systems. But data model heterogeneity and schema heterogeneity make this a challeng... Multidatabase systems are designed to achieve schema integration and data interoperation among distributed and heterogeneous database systems. But data model heterogeneity and schema heterogeneity make this a challenging task. A multidatabase common data model is firstly introduced based on XML, named XML-based Integration Data Model (XIDM), which is suitable for integrating different types of schemas. Then an approach of schema mappings based on XIDM in multidatabase systems has been presented. The mappings include global mappings, dealing with horizontal and vertical partitioning between global schemas and export schemas, and local mappings, processing the transformation between export schemas and local schemas. Finally, the illustration and implementation of schema mappings in a multidatabase prototype - Panorama system are also discussed. The implementation results demonstrate that the XIDM is an efficient model for managing multiple heterogeneous data sources and the approaches of schema mapping based on XIDM behave very well when integrating relational, object-oriented database systems and other file systems. 展开更多
关键词 multidatabase systems common data model schema mapping extensible markup language (XML).
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基于Modelica的虚拟电工电子网络实验室设计 被引量:4
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作者 施正寅 朱善安 《计算机工程》 CAS CSCD 2012年第11期287-289,共3页
为方便学生通过互联网进行电类课程实验,设计一种基于Modelica的虚拟电工电子网络实验室iEEVL。该实验平台利用Modelica进行多课程的统一建模,涵盖电路原理、模拟电子技术、数字电子技术、微电子器件、单片机原理、数字信号处理原理与... 为方便学生通过互联网进行电类课程实验,设计一种基于Modelica的虚拟电工电子网络实验室iEEVL。该实验平台利用Modelica进行多课程的统一建模,涵盖电路原理、模拟电子技术、数字电子技术、微电子器件、单片机原理、数字信号处理原理与技术等课程。仿真结果表明,该平台具有较好的可扩展性,用户可以通过建立新的Modelica模型进行实验。 展开更多
关键词 电工电子网络实验室 虚拟实验 远程教育 统一建模 modelICA语言
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Research on system-of-systems combat simulation model formal specification and representation 被引量:3
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作者 Liu Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期901-909,共9页
To makesystem-of-systems combat simulation models easy to be developed and reused, simulation model formal specification and representation are researched. According to the view of system-of-systems combat simulation,... To makesystem-of-systems combat simulation models easy to be developed and reused, simulation model formal specification and representation are researched. According to the view of system-of-systems combat simulation, and based on DEVS, the simulation model's fundamental formalisms are explored. It includes entity model, system-of-systems model and experiment model. It also presents rigorous formal specification. XML data exchange standard is combined to design the XML based language, SCSL, to support simulation model representation. The corresponding relationship between SCSL and simulation model formalism is discussed and the syntax and semantics of elements in SCSL are detailed. Based on simulation model formal specification, the abstract simulation algorithm is given and SCSL virtual machine, which is capable of automatically interpreting and executing simulation model represented by SCSL, is designed. Finally an application case is presented, which can show the validation of the theory and verification of SCSL. 展开更多
关键词 simulation model formalism simulation model representation system-of-systems combat simulation language simulation virtual machine.
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