铰接式岔枕道岔结构落轴冲击数值分析

考虑岔枕下道床的非线性支承和联结铰结构,建立了三维弹性铰链单元数值模拟方法和整组道岔落轴冲击有限元模型,比较分析了时域与频域内铰接式与普通长岔枕道岔结构的振动响应.结果表明:与普通岔枕相比,铰接式岔枕轨道结构的整体刚度较低,缓和了轮轨冲击,改善了道岔区的综合受力环境;改变了普通岔枕的动态特性,极大程度上降低了高速列车过岔时未行车股道岔枕末端对道床的拍击,减少了道砟粉化,延长了道床养护维修周期;道岔区采用高弹性扣件,可与铰接岔枕组合成优良的弹性基础,优化高速道岔动力性能.     

道岔区板式无砟轨道竖向受力分析

本文将板式无砟道岔系统视为梁-实体-实体组合结构体系,通过Ansys软件建立板式无砟道岔道床的空间有限元模型,采用ADAMS/Rail软件进行岔区结构不平顺仿真,计算了列车过岔的动力响应;选取合适的计算参数,计算分析了转辙器区和辙叉区道床板及底座板的受力变形,为板式无砟道岔的设计、施工提供参考。     

高速道岔辙叉区动力响应仿真分析

通过建立列车过岔有限元模型,运用动力学原理,研究移动荷载作用不同轨下刚度和列车速度在道岔辙叉区对轨道振动特性的影响。分析了心轨尖端、心轨根端及辙叉区共用垫板中心等特殊部位处的轨道振动特性。计算表明列车速度的变化对钢轨最大竖向加速度和岔枕最大竖向加速度的影响较大,而辙叉区轨下刚度的变化对钢轨最大竖向加速度、岔枕最大竖向位移及岔枕最大竖向加速度有较大的影响。     

直逆向过岔列车与桥上道岔耦合振动影响因素分析

针对桥上无缝道岔,运用有限单元法,建立钢轨一岔枕一桥梁弹簧一阻尼空间振动模型;运用弹性系统动力学总势能不变值原理及形成矩阵的"对号入座"法则建立列车一道岔一桥梁空间振动方程组;以温福客运专线田螺大桥为例,拟定桥上铺设了由2组38号道岔组成的单渡线,分析直逆向过岔时,列车运行速度、轨下垂向刚度、枕下垂向均布刚度、岔区垂向不平顺幅值及梁体高度等参数对列车一道岔一桥梁系统耦合振动的影响.研究结果表明:系统响应随列车速度和岔区垂向不平顺幅值增大、梁体高度减小而增加;轨下垂向刚度对系统不同的响应有不同的影响;道岔响应随枕下垂向均布刚度增大而降低.     

提速道岔钢岔枕振动分析研究

钢岔枕是一种特殊形式的岔枕,主要用于道岔牵引点处,可将道岔电务转换杆件置于枕内,有利于大机养护作业。但能否在客运道岔中使用,目前又引起了争议,本研究采用动力仿真分析理论,研究怎么减缓钢岔枕的振动,使之在有碴道床中能与混凝土岔枕具有相同的动力稳定性,从理论上分析提速道岔在改进中采用钢岔枕是可行性。     

道岔平面选型的动力学研究

为合理选取道岔平面线型及尖轨切削方式,基于轮轨系统动力学建立车辆-道岔动力耦合模型,计算不同线型方案下轮轨系统动力响应及其与列车过岔速度间关系,并以18号道岔为例验证此选型方法的可行性.研究结果表明:道岔平面线型设计须同时考虑侧股线型参数和曲尖轨切削方式,满足列车侧逆向进岔时的系统动力稳定性;动力学评价方法可从结构受力及行车状态方面对道岔侧股线型进行分析,并参照系统动力响应随列车过岔速度的变化情况初步确定允许通过速度;对18号道岔而言,增大侧股曲线半径或选用前端半径较大的复圆线型可有效提高行车质量及列车过岔速度,曲尖轨部分采用半切线型或半割线型效果较好,相离半切线型尖轨具有较大粗壮度,可作为主要切削方式之一.     

CDC-16道岔捣固车对有砟道床作业的宏细观力学行为的影响

道岔是实现列车转线的关键设备,是铁路轨道的三大薄弱环节之一,定期进行捣固养护作业是保障列车安全运营的重要手段。但目前针对道岔捣固作业主要依赖实践经验,缺乏理论依据。为研究捣固作业对道岔区有砟道床力学特性的影响,首先,基于DEM-MBD耦合算法,建立CDC-16捣固车捣固装置-钢轨-轨枕-有砟道床仿真模型,实现道岔区捣固作业的有效模拟;其次,开展现场横向阻力试验,验证模型的正确性;最后,分析捣固作业前后道床阻力特性、轨枕竖向位移及道床支承刚度的变化规律,探讨捣固作业次数对有砟道床质量状态的影响。研究结果表明：捣固作业后道床横向阻力降低32.40%,纵向阻力降低28.13%,支承刚度降低86.23%;捣固作业不会改变枕侧、枕底和枕端3部分对纵横向阻力的贡献排序,但对枕侧区域的分担比影响最大;随着捣固次数增加,在一定范围内道床纵横向阻力和支承刚度提升较明显。综合考虑有砟道床质量状态、力学特性以及大机作业效率,建议对道岔区尖轨位置捣固作业以2～3次为宜。     

中国铁路高速道岔技术研究

高速道岔是高速铁路轨道结构的关键，其结构与状态对列车运行安全和运行品质具有重大影响。文章介绍了高速道岔设计参数和平面线形，扣件、岔枕、道岔转换系统等部件主要结构特征，高速道岔设计理论，相关技术条件及取得的创新成果，对于中国高速铁路道岔的进一步研制、试验验证及推广使用具有重要的指导意义。     

12号合金钢组合辙叉单开道岔疲劳裂纹萌生寿命预测

基于有限元分析软件建立12号合金钢组合辙叉单开道岔静、动力学分析模型;基于列车直、侧向过岔的动力仿真结果,确定岔区钢轨疲劳敏感区域,并提取敏感区域疲劳荷载谱;采用静力分析模型研究单位荷载下各敏感区域钢轨内部应力分布情况;基于Miner线性累积法则对岔区钢轨疲劳裂纹萌生寿命进行预测;研究列车轴重、速度对钢轨裂纹萌生寿命的影响;给出不同轴重、不同速度列车通过时岔区钢轨疲劳敏感区域裂纹萌生寿命的预测公式.结果表明:道岔不同敏感区域钢轨的疲劳裂纹萌生寿命相差很大,列车轴重及侧向通过速度对钢轨的疲劳裂纹萌生寿命有很大影响,疲劳裂纹萌生寿命随列车轴重的增加而大幅降低,随列车侧向通过速度的增加也有所降低.     

铁路提速道岔病害原因分析与整治

铁路提速道岔是在普通道岔的基础上进行设备改进,消除道岔限速因素,改善列车过岔的平稳性,以满足快速列车运行的需要。道岔是铁道线路的薄弱环节,其病害是线路设备病害整治的一大难题。为适应铁路提速、重载的发展要求,我国铁路正线道岔     

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。     

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.     

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

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