基于STEP的转子零件CAD／CAPP集成系统

STEP(Standard for the Exchange of Product Model Data)是国际标准化组织制定的产品数据表达与交换标准。介绍了基于 STEP标准的、转子类零件 CAD/ CAPP系统集成的总体结构 ,阐述了系统中主要模块的功能及设计原理。     

基于STEP的转子零件CAD/CAPP集成系统

STEP(Standard for the Exchange of Product Model Data)是国际标准化组织制定的产品数据表达与交换标准.介绍了基于STEP标准的、转子类零件CAD/CAPP系统集成的总体结构,阐述了系统中主要模块的功能及设计原理.     

基于STEP的CAD/CAAPP的信息集成

文章在介绍了CAD系统生成的数据信息和CAAPP的信息需求基础上 ,分析了两者的信息侧重点的差异 ,提出了利用STEP实现CAD与CAAPP信息集成的基本思想及产品装配数据模型 ,论述了基于STEP的CAD/CAAPP集成过程     

网络协同设计动态数据交换系统

动态数据交换是成功实现网络协同设计的关键技术，作者分析了网络协同设计交换数据的特点，研究了网络协同设计动态数据交换中所涉及的数据转换、数据传输、数据操作，提出了异类CAD系统之间的动态数据交换体系结构和动态数据交换组织模式。以STEP为产品数据交换标准，ORA—CLE数据库为系统核心数据库，各CAD系统用户可同时访问ORACLE数据库，实现信息共享和交互。提出STEP—ORACLE动态数据交换组织模式，实现了跨平台异类CAD系统之间动态数据的实时交互和数据的实时一致性。     

基于AP203曲面模型的STEP／IGES转换工具的研究

符合STEP标准与IGES规范的输入和输出是大多数CAD系统的2个数据接口，在目前情形下，这些CAD系统是以“自动化孤岛”形式运作的，实际上存在数据交换和共享的障碍，作者提出利用转换工具来克服这种障碍，文中详细讨论了基于AP203曲面模型的STEP／IGES转换工具的接口方案以及STEP集成资源的程序语言表达，定义了STEP与IGES间的曲面结构映射和实体数据转换，实现了基于AP203曲面模型的STEP／IGES转换工具开发，最后给出了一个应用实例。     

基于STEP标准的三维零件信息系统

分析了CAD集成系统的要求,提出了面向对象的类的特征建模方法与实现方法,给出了基于特征的产品数据集成系统原型以及原型系统的实现过程和技术,实现了基于STEP标准的、可实现自动特征识别的零件信息集成系统,并与传统的集成系统进行了对比,从而得出了此系统的一些特点.     

网络协同设计下基于STEP-OODB动态数据交换

提出了以面向对象数据库(Object-Oriented Database,OODB)作为网络协同设计动态数据交换系统的核心数据库,分析了网络协同设计动态数据交换中所涉及的数据转换、数据传输、数据操作.提出基于STEP-OODB的动态数据交换模式,OODB数据库为系统核心数据库,STEP为产品数据交换标准,各CAD系统用户可同时访问OODB数据库,实现信息共享和交互.实现了跨平台异类CAD系统之间动态数据交互和数据的实时一致性.     

利用STEP/XML的CAD/CAPP信息交换与共享模型及实现

针对异构系统之间难以解决的产品数据交换与共享问题,深入研究了制造信息资源共享、STEP AP203/AP214文件到AP224文件的转换规则等关键技术。采用STEP标准作为CAD系统的信息输出,提出了通过STEP中性文件转换器把CAD系统输出AP203/AP214文件转换成AP224文件,CAPP系统通过AP224中性文件来获取零件的几何和工艺信息的方法。利用STEPAP28所制定的转换规则,将STEP文件转换为相应的XML中性文件,建立XML schema库,以实现制造信息的数据交换和共享。     

从IGES到STEP的产品数据交换研究

主要论述了产品数据表达与交换的重要性,并在分析产品数据交换规范IGES体系结构、数据表达方式及存在问题的基础上,着重介绍了ISO标准STEP的产生、内容、文件结构和EXPRESS语言的表达方法。     

STEP文件的实施方法

STEP标准是CIMS信息集成的核心。采用STEP文件是实现产品数据交换最方便可行的方法。本文介绍了STEP文件实施的基本原理、STEP文件结构和STEP转换器的设计方法。     

Markedness and its Interpretation in Language Use

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Features of Women's language

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.     

A computer generator for randomly layered structures

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

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with