综采工作面开机率多元分析

对综采工作面开机率监测得到的大量数据进行统计与回归分析，确定了开机率与各主要事故率之间定量关系，并找出对工作面生产影响大的因素。     

综采工作面生产过程的动态模拟

本文在对综采工作面进行大量观测的基础上建立了动态模拟模型；通过对生产过程的模拟和故障分析，寻找系统薄弱环节，预测某些薄弱环节改造后综采面可能达到的产量。     

煤层倾角对综采工作面支承压力的影响研究

在煤矿开采过程中,煤层倾角的大小对回采工作面的矿山压力显现会产生很大的影响,针对平顶山八矿实际地质条件,利用FLAC3D数值模拟软件对不同煤层倾角的模型进行计算,研究煤层倾角对工作面支承压力的影响规律,为工作面的安全生产及工作面区段煤柱尺寸等问题提供了理论依据。     

大采高综采面矿压显现规律研究与分析

摘要：本文通过对凌志达煤矿15101工作面支架工作阻力监测与分析,研究了该首采工作面矿压显现规律;结合现场实测与数值模拟手段,对综采工作面回采并巷道变形情况、工作面上下顺槽支承应力分布规律进行了系统的分析研究。结果表明,该工作面矿压显现不剧烈,工作面选用的支架较为合理,同时指出了开采过程中存在的问题,为该工作面的高效安全生产及接替工作面的布置提供了理论和现实依据。     

FLAC-3D在大采高初采工作面顶板力学模拟中的应用

通过FLAC-3D模拟软件,以中能煤业3号煤层大采高2301工作面现场模拟为例,对其开切眼进行建模,并模拟了工作面推进过程中工作面两端头与中部的垂直和水平应力。结合现实工作面矿压情况,对工作面的开采具有实际的应用和指导价值。     

某矿煤层底板采动破坏规律数值模拟研究

为揭示煤层采动破坏规律，在分析工程地质、水文地质及开采条件的基础上。采用Flac有限差分软件对工作面推进过程中底板采动破坏规律进行了模拟研究，得出了工作面推进过程中底板应力场、位移场及塑性区的基本发展变化规律，为煤矿安全生产和矿井水害防治提供参考依据。     

利用计算机模拟普采工作面生产系统

建立模型框图模拟普采工作面生产系统,综合研究各种因素对工作面生产影响。     

综放开采沿工作面倾向顶板垮落规律

为了研究综放工作面覆岩倾向破断规律,采用红外式综采支架压力监测仪,对灵武矿区磁窑堡二矿C142综放工作面矿压进行了监测,利用RFPA 2D数值模拟软件对该工作面倾向覆岩破断规律进行了模拟.研究表明,工作面沿倾向矿压规律明显,直接顶和老顶破断均从工作面上部开始,随着工作面推进,破断位置逐步向工作面中部转移.工作面端头受压力拱保护,压力显现不明显,工作面上下顺槽煤壁支承压力规律明显.本论文对类似工作面矿压监测、生产管理提供了依据.     

涌山矿石门揭煤地应力数值模拟

针对煤矿石门揭煤突出强度大、破坏性强,对煤矿安全生产潜在威胁较大问题,以涌山矿五煤石门揭煤过程中巷道应力变化规律为研究对象,采用FLAC3D数值模拟的方法对石门揭煤过程中地应力的变化情况建立模拟模型,并对其工作面掘进过程进行数值模拟,分析得到研究成果,得出了揭煤过程中巷道周围应力分布的规律,有助于预防煤与瓦斯突出事故.     

基于数值模拟的不同工作面宽度下开采煤层底板流固耦合破坏规律研究

随着煤矿开采业的迅速发展及规模的不断扩大,采煤工作面的宽度越来越宽。采用数值模拟的方法,综合考虑地质构造,煤层开采,矿山压力,含水层水压力等因素,从渗流与应力耦合作用的角度入手建立了底板含水层均布水压流固耦合模型。运用FLAC3D有限差分数值模拟软件对采动工作面底板进行数值模拟,分析了不同工作面宽度下采动煤层底板应力分布状态以及破坏特征和渗流特性。重点模拟工作面推进过程中不同工作面宽度下底板的变形,破坏区域,导升带高度变化情况,得出在进行采矿活动过程中,要在综合考虑多种因素前提下,选取合理的工作面宽度,以保证安全开采的结论。     

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.     

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…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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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。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

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