采场覆岩离层演化的光纤光栅检测实验研究

为定量化研究采场上覆岩层离层规律,采用相似材料物理模型试验的方法模拟煤矿回采过程,用光纤光栅传感技术构建相似材料物理模型实验的覆岩移动的监测方法和系统。实验制作了一个3 m×1.19 m×0.2 m的相似材料平面模型,几何相似比为1∶200,同时在模型内埋设9个光纤光栅应变传感器和1个光纤光栅温度传感器,用以研究模型开挖过程中覆岩运移状态与光纤光栅传感器测试结果的对应关系。实验结果表明,光纤光栅传感器应变量与岩层运移状态密切相关。传感器所在岩层层位发生离层时,传感器受拉应力作用使其应变量发生跃升,而后由于离层不再扩展而保持平稳,直至离层破断垮落。通过光纤光栅检测方法可以定量化描述传感器所处岩层离层变化量的大小。     

光纤Bragg光栅监测沥青混凝土应变试验

基于光纤Bragg光栅(FBG)传感原理,结合沥青混凝土路面的特点,介绍了传感器应变传感特性与设计封装结构,制作了一种用于监测沥青混凝土应变试验研究的光纤Bragg光栅传感器。通过砝码加载的方法对传感器进行标定,光纤Bragg光栅传感器的应变灵敏度系数为1.1 pm/με,封装工艺没有改变光纤光栅的应变传感特性;传感器埋入SMA-13沥青混凝土后,通过静态试验得到荷载与传感器轴向应变之间的关系为0.038 7με/N;通过ANSYS 11.0仿真传感器静态试验,得到传感器应变灵敏度修正因子η为0.928;进行了5 h动态试验,应用其监测室内车辙试验下沥青混凝土内部结构沿传感器轴向的应变,随着碾压次数的增加,轴向的应变增加。监测结果能够反映沥青混凝土内部结构应变基本变化规律,可用于沥青路面的应变监测,为道路养护决策提供了一种新方法。     

相似物理模型变形的光纤光栅传感器检测分析

为了定量化研究相似物理模型实验岩层变形过程,在3m平面应力模型上,安装光纤光栅传感器5个,通过对埋设在相似物理模型中的光纤光栅传感器的采集数据分析,研究了物理模型在微小变形和宏观移动过程中的光纤光栅传感器灵敏度,并与对应位置的百分表数据进行对比。实验结果表明,物理模型岩层变形量小于4.985 mm时,光纤光栅传感器能够准确反映岩层的移动变形情况,两者呈线性变化;变形量大于4.985 mm时,光纤光栅传感器的灵敏度会大幅降低,但其仍然能反映岩层的移动变形状态,研究对岩层变形测试技术的发展有积极作用。     

基于FBG的磁场传感器实验设计方案

光纤Bragg光栅(FBG)传感技术较其它光纤传感技术有其独特的优点，使其更具有研究的价值。基于光纤Bragg光栅的应变敏感性和磁性材料的磁致伸缩效应，提出了将光纤Bragg光栅应用于磁场传感测量的方案。设计方案中将光纤Bragg光栅与磁致伸缩材料相结合。实现了光纤Bragg光栅波长漂移量与侧向位移的线性调谐关系；通过测量光纤Bragg光栅波长漂移量，可以估算出外界磁场的强度变化。     

基于光纤Bragg光栅的采动支承压力分布试验研究

为了研究采动支承压力的分布情况,采用光纤Bragg光栅(FBG)传感器对长壁采场模型试验进行了测试,在模型中埋设了9支FBG应变传感器,对比分析工作面推进时底板支承压力与上位FBG的测试结果。试验揭示了FBG测试结果与支承压力变化呈现镜面反射,在超前支承压力影响范围内支承压力与波长漂移呈线性关系。研究提出了支承压力FBG测试灵敏度参数,其表征了FBG传感器每变化1 pm时的支承压力变化;定量分析了围岩采动支承压力分布规律,得出了测线2三支FBG所在层位的支承压力大小与影响范围(K,L1,L2),同时建立了基于FBG的围岩采动支承压力的分布模型,用于描述采动围岩体中支承压力在不同层位和距离工作面不同距离时的分布规律。     

光纤光栅传感器的现状与发展

概述了近几年国内外在光纤传感器领域的研究热点－光纤Bragg光栅传感器的发展与现状,这种迅速发展的功能光纤传感元件具有其它种类的光纤传感器无可拟的优点,给出了光纤Bragg光栅的基本光学特性,光纤光栅的制作技术,光纤光栅传感器的工作原理,对温度和应变的灵敏度分析以及波长位移信号的解调技术等,最后描述了其前景和主要研究方向。     

光纤Bragg光栅应力增敏研究

应力增敏的研究是光纤Bragg光栅传感的重要课题之一.提出了光纤Bragg光栅应力增敏的模型,推导了该模型的等效弹性模量计算公式,得到了应力与中心波长相对偏移量的关系和应力灵敏度系数表达式,表明通过适当选择弹性体的弹性模量和尺寸,就可以提高应力灵敏度系数.用弹性聚合物封装的光纤光栅理论和实验应力灵敏度系数分别是6.64×10-10Pa-1和6.14×10-10Pa-1,各为裸光纤光栅轴向应力灵敏度的57.8和54.8倍.应力灵敏度系数的理论值和实验值吻合很好.     

采动覆岩运移BOTDA-FBG监测试验

为研究采场覆岩变形破坏特征,采用相似材料物理模型试验的方法模拟煤矿工作面回采过程,用BOTDA分布式光纤和布拉格光纤光栅(FBG)监测采场覆岩运移规律。实验搭建了1.5 m×0.6 m×1.3 m的三维立体模型,几何相似比为1∶150,同时在模型水平方向埋设2根光纤,垂直方向铺设4根光纤,亚关键层埋设2个光纤光栅应变传感器,用以研究模型开挖过程中覆岩运移状态与BOTDA及FBG测试结果的对应关系。试验表明,FBG传感器应变量与岩层运移状态密切相关,可实现对采动覆岩变形破断和离层发育过程的监测。水平光纤测试结果与岩层垮落移动呈明显的对应关系,测试频移峰值间距与岩层垮落顶部离层宽度几乎一致,平均误差不超过3%;垂直光纤频移变化可以反映覆岩垮落及离层发育的动态变化过程。     

简易光纤Bragg光栅测重传感器的制作

设计了一种测量重力的光纤Bragg光栅传感器。光纤Bragg光栅传感器结构形似梯形体,在梯形体的上台面可以放置被测物体,在下台面中间位置需要粘贴光纤Bragg光栅。通过这种结构可以将纵向力转换为横向力,重力测量转换为横向位移测量。实验结果证明,自制的光纤Bragg光栅传感器测量范围在0～3.5 kg之间时,波长与重力呈现较好的线性关系,进程、回程显示具有较好的重复性。     

全光纤分光转动拉曼测温激光雷达探测性能优化

采用光纤Bragg光栅的耦合模理论和转动拉曼激光雷达的温度反演算法,优化全光纤分光转动拉曼测温激光雷达系统的探测性能。以光纤Bragg光栅高斯型谱为基础,构建以光纤Bragg光栅为核心的全光纤分光系统的参数优化模型,以1.5km高度处大气温度的统计误差为优化目标进行仿真分析,得到光纤Bragg光栅的中心波长和半峰值带宽的优化值;为了使均匀光纤Bragg光栅的光谱旁瓣与大气分子的纯转动拉曼谱线匹配,局部优化光纤Bragg光栅的Bragg波长、平均折射率变化和光栅长度等结构参数,以构建光纤Bragg光栅加工系统及设置初始加工参数。结合望远镜耦合效率的仿真结果,分析了全光纤分光转动拉曼激光雷达的探测性能。仿真结果表明,全光纤分光转动拉曼激光雷达系统在高度1.5km处的统计温度误差可达1.3K。     

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)

正~~     

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).     

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.     

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.