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1.
研制了一台二维自动磁场测量系统,它包括测量行程为3500mm的运动定位装置和测量控制系统.采用霍尔探头点测法,并使用“on fly”测量技术对合肥国家同步辐射实验室(NSRL)二期工程新安装波荡器扫描点测量,得到了波荡器场形分布测号结果.并对测号结果讲行了分析。  相似文献   

2.
介绍了一种用于大尺寸,无长导轨干涉测量系统.该系统由两种干涉仪构成.半导体激光光纤干涉仪用于定位,He-Ne激光干涉仪用于测量光程差.文中还就提高定位精度,采用脉冲电流调制方法调制半导激光器作了介绍.实验中,采用100mm导轨,测量距离为800mm,测量误差为±2μm.  相似文献   

3.
测量误差与天文定位误差   总被引:2,自引:2,他引:0  
论述了基于最优估计理论的天文定位方法中天体高度测量精度与定位精度的关系.理论分析和实验表明,即使高度测量精度较差时,仍可获得满意的定位结果.  相似文献   

4.
基于机器微视觉的微结构平面运动测试技术   总被引:4,自引:0,他引:4  
为了对MEMS的微结构平面运动特性参数进行提取和分析,基于机器微视觉构建MEMS动态测试系统,提出模糊图像合成技术.在连续光照明下获取微结构运动图像,利用光学检测方法增强模糊特征带,引入亚像素定位技术提取特征结构边缘,最终获得微结构的平面运动特性参数.实验结果表明,该系统测量误差小于100nm,具有较好的测量重复性精度,与现有系统相比,该系统测量原理简单,实现方便,且能满足微结构的测试需求.  相似文献   

5.
薄孔壁厚和小孔径测量系统   总被引:5,自引:0,他引:5  
由于相邻孔壁厚度的测量根据进刀量进行计算时精度很低,故提出了一种应用电容传感器对2个微小孔间相邻孔壁进行精密测量的系统.基于非接触式电容测孔传感器,研究了测头的电场边缘效应影响及保护环的宽度选择,设计了电容瞄准测孔传感器的测头对相邻小孔中心定位,利用电容差动测厚传感器测量孔壁,系统由1个瞄准测孔传感器和2个差动测厚传感器及三通道测量电路组成,处理数据后直接显示孔径和孔间壁厚.系统属非接触测量,无需修正测头及工件变形误差,实验证明,测量精度为0.5μm,  相似文献   

6.
讨论了曲面切槽单色器的工作原理,并依据合肥光源上的XAFS光学参数,设计加工出晶体的切槽曲面,测量了曲面的形位误差,进而分析了曲面加工、定位误差以及入射光的束宽对单色器分光性能的影响.在测量所得的加工误差下,考虑由于束流宽束给衍射性能造成的影响,计算了实际晶体相对于理想晶体的理论衍射效率.计算结果证明该晶体单色器完全适用于合肥光源的XAFS光晕系统.  相似文献   

7.
在对现有检测方法加以综合分析的基础上,对直流系统的绝缘监测技术进行了详细的研究,给出了直流系统漏电流大小与被测时间量之间的关系,阐述了直流系统接地故障点的测量定位原理,并给出了绝缘监测故障定位装置的结构。  相似文献   

8.
用于微波天线的三维面形测量技术   总被引:1,自引:0,他引:1  
在三维立体视觉测量原理的基础上,建立了用于微波天线面形测量的三维视觉测量系统,分析了该测量系统优于其他测量系统的主要优点,给出了测量原理,介绍了系统组成及其功能,通过对微波天线的面形测量,验证其可行性,对空间点位进行多次重复测量表明:x,y方向的测量标准差优于0.1mm,z方向的测量标准差优于0.18mm,满足微波天线的面形测量要求。  相似文献   

9.
基于运动控制技术的非球面测量系统   总被引:1,自引:0,他引:1  
为满足非球面光学元件表面精度的测量要求,设计和实现了一种高效数控非球面测量系统.系统基于运动控制技术,构建了四轴联动的测量工作平台.根据数据采集原理,实现对非球面工件表面形位参数进行连续采样.整个系统采用工控微机作为上位机非实时控制,下位机采用高速DSP进行实时控制.在Windows操作系统下,用Visaul C++开发工具完成了测量系统的软件开发.最后通过实验对测量系统的稳定性及其误差进行了分析.实验结果表明,系统行程为100~120mm,系统误差小于5μm,能满足普通光学非球面元件测量精度的要求,同时系统体现了较好的通用性和可靠性.  相似文献   

10.
韦旭 《科技资讯》2006,(23):36-36
RTK实时动态测量技术是继CPS全球定位技术之后,测量领域又一次技术革命,能够极大地提高工作效率.本文介绍了RTK技术及其在城市测量中的应用,分析了RTK技术应用于城市测量的注意事项,并对RTK在实测中遇到的问题提出建议。  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

17.
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。  相似文献   

18.
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   

19.
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   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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