陡煤采空区稳定性评价的信息融合模型

为评价陡煤采空区稳定性,分析了陡煤矿区地质特点和稳定性影响因素,根据时空观思想建立了由3个二级指标和7个三级指标构成的稳定性评价指标体系;利用信息分配和信息扩散原理构造概率分配函数,结合D-S证据推理理论,建立了陡煤采空区稳定性评价的信息融合模型.验证了信息融合模型对陡煤矿山采空区稳定性评价是适应的.该方法对类似地质条件的矿山采空区稳定性评价具有借鉴作用.     

三昌采石场复杂采空区群稳定性数值模拟研究

三昌采石场采空区具有规模大、数量多、空间关系复杂等特点,急需开展复杂采空区群稳定性课题的研究.在对采空区群及其开采环境现场调研的基础上,进行了现场点荷载试验与室内单轴抗拉、抗压强度实验,获得岩体力学参数.采用三维有限元方法对三昌采石场进行数值模拟,模拟结果表明:三昌采石场采空区稳定性偏低,部分空区顶板出现拉应力集中,有可能出现顶板冒落.根据分析结果,提出了相应安全对策,为矿山的安全生产起到指导作用.     

基于空区结构效应的残矿开采作业环境安全辨识与协同利用

针对西部某矿山目前开采现状和大量遗留残矿的采空区结构特征,在采空区作业环境安全评价的基础上,提出协同利用空区空间的残矿开采模式,即采空区的空间直接利用作为采准过程的补偿空间和切割空间、加固处置协同利用的补偿空间、密闭封存安全保护、散体充填密闭处理和胶结充填应力环境再造等,并以R3空区作为实例提出空区协同利用的采矿方法和出矿等生产工艺.应用未确知测度理论,利用采空区结构效应的空区跨度(X1)、空区暴露面积(X2)、空区高度(X3)、空区埋深(X4)、矿柱尺寸布置(X5)5个参数,对西部某矿群空区下的残矿开采作业环境进行安全辨识和分级.研究结果表明:该方法对采空区群下残矿开采作业环境的安全评价简单可行,通过采空区的结构效应获得了残矿开采作业环境的安全分级辨识.     

一种多层采空区群稳定性的综合评价法

为准确评价多层采空区群的稳定性,考虑到数值模拟的局限性且采空区稳定性影响因素较多,提出数值模拟分析(整体分析)与多级模糊评判(单个分析)相结合的综合评价方法。以实际工程为例,建立矿体及采空区群三维整体数值模型,并利用FLAC3D软件研究其应力分布和塑性区(结构塑性强度破坏方面)以及采空区顶板中点位移监控(变形控制方面)。采用多级模糊评判对单个采空区的稳定性进行评价,对比分析这2种方法的异同,以便得出更准确的稳定性分类。研究结果表明:1号、2号和11号空区,处于不稳定状态,13号等9个空区处于较不稳定空区;采用该综合评价法所得的评判结果能更好地反映复杂多层采空区群的稳定程度,精度较高,为矿山复杂多层采空区群稳定性评价提供了一种新的可行的思路和方法。     

采空区治理技术及其适用性

长期以来,应用留矿、空场等采矿方法开采的矿山,空区没有得到及时处理,相继发生了顶板崩落和地表岩移等灾害.考虑到影响岩体移动的不同因素,空区开采引起岩层移动将显现不同特征,所带来的影响也不同.因此在了解采空区治理技术及适用性的基础上,选择合理的空区处理方法以减少引起空区岩体移动产生的危害具有实际意义.     

基于D-S证据理论的岩体质量分级组合评价方法

现有岩体质量分级方法评价结果存在非一致性的问题.为此,在组合评价思想的基础上,选取多种岩体质量分级方法作为基础分级方法,建立了岩体质量分级组合评价计算模型.并考虑到D-S证据理论是一种较严谨的不确定性推理方法,其具有较强的信息融合能力,并且能够反映不同信息之间的一致性和冲突性,将其引入建立一种新的组合评价方法合成规则.然后,针对D-S合成规则需要解决确定基础分级方法基本概率分配函数这一问题,引入欧氏距离建立基础分级方法基本概率分配函数的确定方法,从而最终建立基于D-S证据理论的岩体质量分级组合评价方法.最后,工程实例分析表明,3种基础分级方法存在冲突性,但是D-S证据理论能够较好地解决这一问题.     

中小型金矿山采空区处理方案

以某典型中小型金矿山的采空区为研究背景,结合空区特点提出了封堵治理方案,矿山严格按着设计方案进行操作,可以满足安全要求,对类似矿山有一定的指导作用.取得以下结论:(1)总结分析了矿山开采空区现状与地质及水文开采技术条件.(2)对现有采空区的安全隐患进行了分析评价.(3)提出了在地表修建护栏网、井下废弃巷道进行封闭等措施的空区处理方案.(4)制订了封堵过程中安全技术措施,并从地压管理、通风等方面给出了安全防范措施.     

急倾斜煤层采空区结构特征GPR探测

急倾斜煤岩体结构和地质缺陷具有隐蔽性。历史性无序开采形成的采空区分布的不规则性严重影响安全开采。以神新小红沟煤矿急倾斜煤层开采区域空区分布规律预测与参数确定为目标。通过理论分析、GPR地面与地下立体联合探测,分析了+522水平B3和B6开采扰动范围内采空区结构特征。+522水平距五一煤矿巷道垂直距离约为35.0～35.5 m.B3巷1 214～1 232m范围内空区覆岩破坏严重,多处出现破碎区。空区下部近似椭圆,上部似半椭球体结构,且空区已联通。1 232～1 250 m范围空区及覆岩破坏严重,局部区域积水量大,为现场开采设计与灾害防治提供科学依据。     

采空区群蠕变突变三维力学模型构建及稳定性精确预测

针对双向分层条式充填采矿法空区群特点,系统地构建顶板和矿柱为一体的三维空间力学模型,引入弹性力学和结构力学相关理论,推导出3种边界条件下顶板中心下沉挠度的曲线方程。综合运用突变和蠕变理论,从能量转化角度阐明采空区群突变机理,建立采空区群系统突变失稳计算流程,导出采空区群顶板蠕变微分方程,实现对采空区群突变失稳规律和稳定时限的精确预测,通过实例计算和数值模拟分析,验证其有效性。此外,全面分析影响采空区群稳定性的主控因子,并得出影响因子的影响程度。通过调节影响因子参数,可预测控制采空区群稳定性,选择最佳充填时机,优化采场结构参数。研究结果表明:采空区群系统稳定性与矿柱支撑面积率、矿柱峰值抗压强度、矿柱弹性模量呈正相关,与顶板均布荷载呈负相关;当顶板-矿柱系统处在固支模式时,采场参数对系统稳定性影响最显著;当采场参数足够大时,固支模型和简支模型对系统稳定性影响差距不明显。     

群空区稳定性聚类分级及处治对策

为对群空区进行稳定性分级及综合处理研究,在前期空区探测的基础上,基于三维数值模拟程序M1DAS/GTS与FLAC 3D耦合对采空区的稳定性进行模拟分析,综合考虑顶板最大位移、最大主应力、最小主应力等3个因素对群空区进行聚类分级,并在此基础上提出群空区的综合处治对策.结果表明:运用模糊聚类分析方法,实现最大顶板位移、最大...     

Markedness and its Interpretation in Language Use

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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