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1.
标准建模语方UML是一种新兴的面向对象的建模语言。介绍了它的发展状况,主要特点以及前景。卫星移动通信是未来移动通信的重要发展方向,但设计一个完善且实用的卫星移动通信系统并不容易,探索用UML对卫星移动通信系统设计软件进行建模,并以此为例,详细地阐述了UML的形式、内容和使用方法,由此对UML形成初步的较完整的认识,并完成卫星移动通信系统设计软件的建模过程。  相似文献   

2.
讨论中低轨卫星移动通信的系统设计问题 ,包括星座设计、覆盖率统计和通信线路计算等问题。运用统一建模语言UML、面向对象可视化编程软件Delphi、科学计算软件Matlab、动画制作软件Animator等工具 ,研制了中低轨卫星移动通信系统设计综合软件 ,并以此设计了我国中低轨卫星移动通信系统的星座方案各一套 ,同时完成了星座实时动态演示 ,并能实时对全球、中国、北美、欧洲进行覆盖率动态统计和通信线路计算。  相似文献   

3.
基于UML的面向对象编程在直接转矩控制系统中的应用   总被引:3,自引:0,他引:3  
把面向对象的方法运用于控制系统设计,并利用UML的建模机制和特点,以UML为建模语言,同时以Rational ROSE为工具对直接转矩控制系统进行面向对象建模。  相似文献   

4.
张治国 《科技资讯》2007,(28):50-51
面向对象技术是软件工程领域中的重要技术,统一建模语言UML则是近几年国际上比较流行的面向对象的标准建模语言.本文阐述了基于UML建模的图书馆系统的开发.建模是开发优秀软件所有活动的核心部分,也是本文工作的重点所在.基于这个过程我们从系统分析,设计,实现与测试,运用UML建模思想与各种模型对图书馆系统进行了详细的描述.  相似文献   

5.
介绍统一建模语言(UML),UML支持从需求分析、系统设计到具体实现的软件开发全过程.利用UML建模对高校科研信息管理系统进行分析设计,探讨了UML在面向对象需求分析中的应用.UML建模不仅能够建立可靠、完美的系统结构模型,而且可以更好地帮助开发人员理解系统中各项业务流程,方便用户和开发人员之间的交流,提高系统开发的效率.  相似文献   

6.
统一建模语言(UML)是一种可视化的面向对象的建模语言,可用于对软件系统进行描述和构造软件的系统结构。本文介绍了UML的主要内容,并以图书馆管理系统为实例,探讨了应用UML建模机制,对系统的需求分析、详细设计及实现的不同阶段的建模过程。  相似文献   

7.
杨丹 《科技信息》2007,28(33):90-92
面向对象开发方法在软件界的流行,直接引起了面向对象建模语言的兴起,UML(Unified Modeling Language)作为一种面向对象的统一建模语言,正在逐渐地被软件界和商界所认可。然而对于使用该语言建立的各种模型如何进行度量?有哪些具体的指标可供使用?又如何取得这些度量值以便在开发早期对系统规模做出总体估计却没有被很好的重视和研究。本文即根据对移动通信系统的建模实例,不仅介绍了如何利用UML的图示对整个系统进行建模,同时一并给出了对模型进行度量的参考指标。  相似文献   

8.
统一建模语言UML (Unified Modeling Language)是一种标准的图形化建模语言,它是面向对象分析与设计方法的表现手段,适用于不同的开发环境和软件生命周期.文中主要讨论如何使用UML完成高校学生个人信用评价管理信息系统的用例建模、静态建模和动态建模,以提高该系统的文档化、可视化和标准化,并保证系统的可靠性和可用性.  相似文献   

9.
运用统一建模语言UML(Unified Modeling Language),提出了一种关系型建模方法,并实现了一个原型系统,能够对UML中蕴含的部分设计信息进行建模与抽取.所得到设计信息能够应用于软件重构及面向方面编程中,能够挖掘设计阶段形成的语义信息,有效地帮助开发人员进行软件重构.  相似文献   

10.
UML属于可视化基于面向对象的建模语言,文章简单地介绍了有关UML的开发过程以及UML的建模技术,通过对UML的视图,UML的开发过程以及UML的的组成与优势进行了分析争研究,介绍了有关UML的建模技术在相关软件的开发过程中应用效果.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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