基于MasterCAM平台的数控加工

介绍了MasterCAM软件的CAD/CAM功能。结合连杆数控加工实例,阐述了在MasterCAM环境下进行零件造型、工艺分析、刀轨生成、仿真加工、后处理程序、机床加工等数控加工的一整套过程。运用该软件,可避免繁琐的手工编程,提高加工效率,保证零件的加工精度,实现高效优质的数控加工。     

应用MasterCAM实现数控自动编程与加工

本文主要通过MasterCAM软件在数控加工中的一个应用实例，介绍了在数控加工过程中运用该软件进行机械设计和加工的基本流程结合侧板零件的加工实例，详尽地讲述了MasterCAM强大的CAD／CAM功能。     

基于MasterCAM的米奇卡通玩具凸模的数控编程与加工

以一米奇卡通玩具凸模的数控编程与加工为例,较为详尽地讲述了运用MasterCAM软件进行数控编程与加工的方法和策略,为模具的数控加工提供借鉴。     

MasterCAM在数控教学中的应用

华中Ⅰ型数控系统是国内用于数控教学的主要系统之一；MasterCAM是微机平台上使用最为广泛的CAD／CAM软件系统。将MasterCAM结合华中Ⅰ型数控钻铣床用于数控教学，不仅可以简化加工代码编写的步骤，而且可以大大提高程序的质量。     

上下异形零件的线切割自动编程

上下异形零件的加工是线切割数控加工中的难点问题.通过一个典型的加工实例,在探讨零件的加工原理和加工工艺的基础上,提出利用MasterCAM软件进行零件的造型和线切割自动编程,能有效提高上下异形零件的加工精度与加工效率.     

基于MasterCAM X的数码相机面壳凹模数控加工

本文以某一数码相机面壳凹模为加工对象,分析其结构特点及数控加工工艺要求,在此基础上制定了从粗加工到最后的较陡峭曲面的余留残料加工的整个加工工艺过程,加工实际说明,这一加工过程能够满足数码相机面壳凹模的各项质量要求。突出了MasterCAM软件数控编程的方法,为数控编程加工提供参考,对提高编程效率和实际应用水平有较大的帮助。     

自动编程应用实例

随着零件复杂程度的增加,数学计算量、程序段数目也将大大增加,这时需要自动编程来完成数控加工程序的编制。本文介绍了一种自动编程数控加工的方法,使用Pro／E软件造型,导入MasterCAM进行刀路设计,后处理生成数控加工程序,然后传输到机床上进行数控加工。此方法简单易用,大大提高了数控编程的效率,能有效地保证数控加工的精度。     

端面凸轮参数化建模与仿真加工

通过用三维软件Pro/E对端面凸轮进行参数化的实体建模,再将模型文件导入到MasterCAM中进行数控仿真加工并获得数控加工代码,以降低端面凸轮回转时螺旋线的直线度误差,提高端面凸轮的端面回转接触精度。通过端面凸轮的参数化设计缩短了该产品的开发周期,提高了设计效率。同时借助三维软件可对端面凸轮的实体建模进行必要的运动仿真,通过观察、分析和判断模拟运动过程实际工作情况,以尽早发现设计过程中存在的缺陷,采用MasterCAM的仿真加工与接触精度的修正,避免了实际加工中的不必要的原材料损耗。为端面凸轮的设计与研究提供了一条新思路。     

SINUMERIK802D数控系统基于MasterCAM9的后置处理器

通过分析MasterCAM9后置处理程序的结构,结合基于SINUMERIK802D数控系统的KVC650B立式加工中心的编程特点,开发了专用的后置处理器,使MasterCAM9生成的NC程序能够直接应用于KVC650B加工中心上加工。实际应用表明:该专用后置处理器可以提高MasterCAM9编程效率,实现数控加工自动化。     

关于MasterCAM绘制公式曲线的探讨

随着现代制造技术的发展和数控机床的日益普及,数控加工得到广泛的应用,越来越多的人正在学习和使用数控自动编程。目前在我国的数控加工行业中,自动编程软件有很多种,MasterCAM就是其中一种应用非常广泛的自动编程软件。自动编程造型时常常会遇到需要绘制曲线的情况,虽然MasterCAM软件利用其中的绘图工具按钮可以直接绘制多种曲线,如椭圆、盘旋曲线、螺旋曲线、样条曲线等,但还是有很多曲线不能用绘图工具按钮直接绘制,如正弦曲线、抛物线、双曲线等,而这些曲线都可以用公式来表达的,是有规律的,本文就此类曲线的绘制问题进行探讨。     

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.     

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.     

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.     

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-