基于取样光纤光栅的温度-应变交叉传感器

设计了一种基于取样光纤光栅的温度-应变交叉传感器,应变测量范围为0~2 000με,温度测量范围为-50~200℃.仿真验证获取了取样光纤光栅的传感特性.应用SPSS统计学软件,得到取样光栅同时测量温度和应变的双参量矩阵方程,并标定了矩阵方程中的4个传感系数.     

基于薄壁应变筒的光纤布拉格光栅压力传感器

综述光纤布拉格光栅的传感机理，研制基于薄壁应变筒的光纤布拉格光栅压力传感器。该传感器力灵敏度高，同时又能实现温度补偿；其结构简单，易干工业化生产。对静态特性实验研究结果表明，该传感器系统具有比常规的压力传感器更优越的性能，     

光纤光栅传感器的原理及应用研究

作为性能优良的敏感元件,均匀光纤布拉格光栅、啁啾光纤布拉格光栅等多种传感器已经有了更多的直用领域。通过光纤布拉格光栅内部写入、干涉法侧面写入、相位模版法写入等制作技术的原理说明和对比评介,通过光纤光栅传感器对所在环境的应变、应力、温度变化和动态磁场的感应原理分析,以及对光纤光栅传感器在复合材料、电力系统、石油天然气井和建筑结构中的应用工程的综述,阐明了这一类传感器件在单参数传感测量,特别是多参数传感测量中还育很大的发展空间,值得进一步研究。     

光纤光栅温度补偿实验研究

分析了光纤布拉格光栅对温度和应变传感的响应机制,对光纤布拉格光栅传感中的应变和温度交叉敏感问题进行了讨论,在此基础上提出了采用参考光栅实现光纤布拉格光栅应变传感时的温度补偿的基本原理和方法,并通过实验进行了验证。理论和实验均证明,与其他温度补偿方法相比,笔者提出的参考光栅温度补偿法原理简单,补偿效果好。     

一种光纤光栅加速度传感系统

研制了一种高精度、低成本适合于地震勘探和矿山安全等工程领域的光纤光栅加速度传感系统。该系统利用加速度改变光纤光栅中心波长的原理工作,可以有效消除温度漂移对动态应变测量的影响。实验结果表明,传感器频响在2-100Hz,灵敏度1．2pm／με,动态范围达80dB,是一种较为理想的光纤加速度传感系统。     

单布拉格光栅光纤压力温度双参量传感器的研究

光纤布拉格光栅(FBG)传感器采用普通悬臂梁对非温度物理量进行测量时,存在温度交叉敏感的问题.针对该问题,提出一种基于双厚度等腰三角形的双参量传感器悬臂梁结构,通过理论分析与仿真验证了该结构的可行性,并将单FBG光栅放置于该结构厚度变化交界位置构成双光栅传感.通过光纤传感理论推导和实验系统验证了温度、压力与FBG反射光谱的双波峰共模函数值、双波峰波长差之间的关系.实验结果表明该结构可以实现压力和温度的同时测量,通过双厚度等腰三角形悬臂梁传感结构可有效解决温度交叉敏感问题.     

基于波纹管杠杆组合结构的光纤光栅压力传感器设计

针对井中水压高精度测量的需求,基于波纹管的压力传感特性,及悬臂梁的杠杆放大结构,设计了一种高灵敏度的光纤布拉格光栅压力传感器,通过弹性片连接的杠杆结构将压力作用下波纹管的轴向变形放大为光纤布拉格光栅的轴向应变,以实现压力的高精度测量。建立了传感器机械结构的力学模型,推导了传感器中光纤布拉格光栅中心波长变化与压力的数学表达式,并通过有限元方法对传感器的压力灵敏度进行了仿真。该传感器仿真和实验压力灵敏度分别为14.8 pm/kPa和14.1 pm/kPa。该压力传感器能够对小量程范围内的压力进行准确测量,同时可以通过改变杠杆臂长参数改变传感器的灵敏度,调整其测量量程。     

基于均匀光纤光栅F-P腔温度传感器的设计

论述了均匀长周期光纤光栅和布拉格光纤光栅的反射特性,提出用均匀长周期和布拉格光纤光栅形成F-P腔,给出了F-P腔的反射率公式,用Matable计算了F-P腔中心反射波长随温度的变化,并用实验进行了测量．设计出用均匀光纤光栅F-P腔作为传感元件的温度传感器系统,并对温度变化进行了测量．结果表明,均匀光纤光栅F-P腔的中心反射波长与温度具有良好的线性关系,传感器系统的温度测量误差在±0．4℃以内．     

一种高精度光纤光栅位移传感器设计研究

本论文以光纤光栅传感理论及光纤光栅位移传感器为研究内容,结合导师科研项目,利用布拉格光栅特殊的结构特性,设计并研制出一种基于行星轮系的大量程高精度布拉格光栅位移传感器,并对新的光纤光栅位移传感器原理、测量灵敏度、量程进行了理论分析和实验研究。     

应用FBG传感器测量高性能混凝土梁养护早期性能

在高性能混凝土构件无载荷养护早期,混凝土较大的自生收缩和温度变形在混凝土结构内部产生微裂纹将对高性能混凝土结构的耐久性产生不可忽视的影响。运用光纤布拉格光栅（FBC）埋设型传感器成功检测了高性能混凝土梁构件在其无载养护早期的应变和温度变化。由于布拉格光栅同时感应温度变化和应变,因此需要设置FBG温度传感器来补偿应变传感器的温度影响。FBG双传感器成功检测了高性能混凝土梁构件的早期变形性能和温度变化,试验结果表明高性能混凝土梁在养护早期无载阶段的自收缩变形比较大,浇注养护18h达到430με的最大值,同时分析了减水剂用量对高性能混凝土早期变形性能的影响。     

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.     

A computer generator for randomly layered structures

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

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。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

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

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.