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1.
国内金刚石绳锯   总被引:4,自引:0,他引:4  
阐述了金刚石绳锯的基本组成、工作原理、金刚石串珠绳的结构以及金刚石串珠的类型,通过对我国几种主要金刚石绳锯的介绍,总结了国内金刚石绳锯和串珠制造形式的发展现状,分析了目前我国金刚石绳锯发展的不足,展望了其发展趋势以及广阔的应用前景。  相似文献   

2.
本文分析了绳衬钢度对单绳双摩擦轮提升中钢绳过渡张力的影响、两摩擦轮绳槽的磨损和两摩擦轮间半径差变化的规律及钢绳在摩擦轮上的窜动.并指出该提升机专用于提升载荷时,绳槽半径差和钢绳过渡张力波动都将随提升次数增加而减小.反之,该提升机专用于下放载荷时,绳槽半径差和钢绳过渡张力波动都将随提升次数增加而增加.最后给出该提升机绳槽半径差的测算方法.  相似文献   

3.
为掌握金刚石绳锯机在水下切削作业时的工作状态,并能及时对作业参数进行调整,设计了一种水下金刚石绳锯机监测系统。分析了绳锯机切削作业时的切削参数,选取切削速度、进给速度、张紧力、串珠绳位置和液压系统进行监测。硬件采用基于ARM7TDMI-S核心的处理器LPC2214,配合监测传感器、存储器、RS232通讯和LCD显示器组成硬件系统。分析了监测系统软件设计思路,对数据显示和数据处理进行模块化设计。经过测试,显示器可以实时显示绳锯机的主要作业参数。该设计实现了水下金刚石绳锯机作业参数的可靠监测,对提高绳锯机的水下切削效率有重要意义。  相似文献   

4.
多绳摩擦提升机钢丝绳张力在线监测传感器   总被引:2,自引:0,他引:2  
介绍一种新型矿用多绳摩擦提升机动态张力监测传感器,采用圆平面压力弹性膜作为变极距差动电容信号输出,传感器弹性敏感元件与转换电路休成一体化全封闭设计制造,具有良好的抗振动和抗冲击性能,适用于井下恶劣工作环境。  相似文献   

5.
通过对贮绳机构钢丝绳排列调整问题的分析,介绍了排绳螺杆电动调整装置研究开发的过程,阐述了该装置的基本原理、结构特点和技术难点,现已成功地在某船厂进行使用。  相似文献   

6.
为模拟人臂腕关节的结构功能,提出了有别于传统仿生关节的3自由度绳驱动并联结构,即通过球副连接动平台与静平台实现腕关节的转动功能。考虑绳驱动的冗余特性和绳索的单向受力性,对机构的位姿结构进行静力学分析,获得绳索张力表达式,同时建立绳张力分布优化模型,通过遗传算法得到绳拉力分布情况。通过建立运动学和静力学方程对机构进行受力分析,并引入线矢量和微分变换的方式,推导出机构的固有刚度和可控刚度,建立了腕关节静态位姿结构刚度模型,并给出刚度评价指标。分析绳索张力与机构刚度的关系和可控刚度对整体刚度的影响,数值仿真分析得出腕关节机构的位姿结构刚度在工作空间中的分布规律。  相似文献   

7.
以Atmel公司的为控制器,以纱线张力为研究对象,阐述系统的硬、软件实现方案,并分析张力测量传感器——霍尔传感器的纱线张力变化,设计纱线张力检测方案。系统将采集到的结果经A/D模块转换信号,实现LED实时显示;准确且自由地设置上、下限纱线张力;当纱线张力值超范围时,实现声光报警;并采用PWM信号控制电机,拉回张力至正常状态。结果表明,系统设计与检测方案简单,可行性较高,成本较低。  相似文献   

8.
基于光纤光栅传感原理研制出一种监测孔隙水压力的新型光纤Bragg光栅渗压传感器,并进行了室内标定和现场试验。该传感器可将过滤后进人传感器腔体的水压引起的光栅反射光波长的变化灵敏直观地显示出来,从而实现孔隙水压力的实时监测。与常规的电类检测仪器进行的对比试验表明:该传感器不仅能达到常规仪器的监测效果,而且具有绝对数值测量,抗干扰能力强,结构简单,长期稳定性高,能很好地实现对土木建筑结构的实时、在线监测等独特的性能,在土木工程界具有广泛的应用前景。  相似文献   

9.
将绳驱动并联机器人应用至外墙清洗领域,并对清洗机器人的动力学建模及张力优化进行深入研究。首先,确定机器人的构型为完全约束绳驱动并联机器人,并建立了考虑绳索弹性的动力学模型;其次,针对该类型绳驱动并联机器人绳张力解不唯一问题,提出将相关力改进的最小方差作为优化目标对绳索张力进行优化。最后,通过Simulink-Adams进行联合仿真验证。结果表明,优化后的绳索张力光滑连续变化。系统开环的情况下,圆形轨迹最大误差均值为0.071 m,终点误差均值为5.15 mm;直线轨迹最大误差均值为9.25 mm,终点误差均值为3.5 mm。解决了完全约束绳驱动并联机器人绳索张力不唯一、不连续问题,并为控制策略研究提供理论依据。  相似文献   

10.
对传统"硬式"支撑系统和"软式"张线支撑系统,以及绳牵引并联支撑系统的支撑形式进行分析.对比实验结果表明,低速风洞试验的静导数测量采用"软式"支撑系统较好,张线支撑系统只能实现静导数测量;绳牵引系统不仅具有张线测量静导数时的全部优点,而且还可以实现单自由度的和多个姿态角组合的飞行器模型的多种振荡运动时的动导数测量.在传统风洞试验基础上,结合绳牵引系统的自身特点解析,归纳绳牵引支撑风洞试验系统的静导数和动导数的气动导数解算原理.  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.
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   

13.
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   

14.
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   

15.
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.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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-  相似文献   

20.
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-  相似文献   

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