同步带传动的计算机辅助设计

利用计算机辅助设计，设计程序ＳＢＤＡＰ，完成了同步带传动设计及带齿间的载荷分配计算。在传动设计基础上，通过对齿间载荷分配分析，可以调整齿形参数，以达到提高带的传动寿命。     

基于Romax Designer的NGW型行星齿轮箱传动性能分析

针对有效评估NGW型行星齿轮箱传动性能的问题,在完成齿轮基本参数设计的基础上,采用Romax Designer分析行星传动系统的传动性能。首先,以齿根弯曲强度为设计准则,确定NGW型行星传动系统中齿轮基本参数;然后,通过无干涉啮合条件并以齿面接触疲劳强度的校核准则,验证了所设计的NGW型行星传动系统能够满足运动条件和齿面接触要求;最后,基于Romax Designer建立NGW型行星传动系统的几何模型,并分别以最大齿面接触应力和各齿轮传动误差与单位齿宽载荷为指标对这一模型展开静态分析和动态分析。研究结果表明:内/外啮合副的传动误差波动幅值均小于1.4μm,且各齿轮单位齿宽载荷波动值均小于90 N/mm,行星传动系统传动性能良好。     

渐开线少齿差传动的轮齿载荷研究

与一般齿轮传动不同,在渐开线少齿差传动中存在多齿同时接触现象,因而其载荷分配系数要小得多.本文在对几何关系、轮齿变形和制造误差进行分析的基础上,建立了描述多齿啮合状态的数学模型.计算表明,同时啮合齿对的数目一般不大于5对,载荷分配系数随齿数和载荷集度的增加而减少.本文给出了不同载荷集度、不同传动参数下载荷分配系数的均值和标准差,可用以确定轮齿载荷的分布特征.本文的结论得到光弹性实验的验证.     

摆线针轮传动输出转角滞后分析

提出一种分析求解摆线针轮传动误差的有效的新方法。该方法不仅可分析求解传动误差，亦可找出最先接触的针齿。解决了载荷分析、强度计算等有关这种传动性能分析的一个基本问题。     

磁力金属带传动效率的理论计算与试验

磁力金属带传动(MBDM)是基于摩擦传动理论和电磁学理论构建的一种新型摩擦传动．研究了MBDM的功率损失及传动效率，分析了其影响因素，并通过实验加以验证．结果表明，MBDM通过电磁吸引力和初张力的耦合作用产生摩擦力，传递运动和动力，具有传动功率大和效率高等特点．MBDM稳定运行时的传动效率可稳定在95％～98％，并随磁感应强度的增加而提高、     

齿轮传动误差的平均法测试原理

齿轮传动误差可采用不同的测试方法来获得。本文阐述了采用平均方法测试具轮传动误差的原理并给出求平均值系统及相应的测量结果，实践证明，该城齿轮回转时测试其传动误差是很有效的，其动态运动和理论计算是相符合的。     

蜗杆副传动接触线载荷的研究

建立了蜗杆副在常规的润滑与磨损传动条件下,齿面接触线载荷的计算模型,结合蜗杆副传动的润滑与磨损规律特点,阐明了蜗杆副传动中,弹性流体动力润滑油膜和齿面磨损状态对齿面接触线载荷变化规律的影响。     

拖拉机传动系动载荷的研究

本文叙述了理论研究拖拉机传动系动载荷的方法,即建立动力模型、数学模型及用电子计算机解运动微分方程组;并对某65马力轮式拖拉机带几种农机具各档起步时传动系动载荷的变化及离合器不同接合速度对传动系动载荷的影响进行了研究。     

滑动摩擦和啮合相位对齿轮中心双流传动动力学的影响

为了研究滑动摩擦和相位调谐对齿轮中心双流传动动力学的影响,建立了考虑时变啮合刚度、阻尼、滑动摩擦、相位及支承刚度和阻尼的齿轮中心双流传动系统扭转－横向振动耦合模型。通过对渐开线直齿轮副啮合过程的分析,推导了系统中与摩擦有关的计算公式,并采用数值仿真法研究了滑动摩擦、相位调谐对齿轮动态传动误差和支承动载荷的影响,研究结果表明滑动摩擦对齿轮支承动载荷影响很大,采用相位调谐可有效地降低系统动态传动误差及中心轮的支承动载荷。     

行星齿轮传动均载问题的研究

行星齿轮传动只有在载荷分配均匀情况下才能发挥传动比大、结构紧凑、效率高、承载能力大、传动平稳等优点.阐述了行星齿轮传动均载问题在国内外的研究现状、行星轮间载荷分配不均的原因、常用的均载方法,指出了行星齿轮传动均载问题需要进一步研究的几个问题.     

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-