STUDY ON THE COAL-ROCK INTERFACE RECOGNITION METHOD BASED ON MULTI-SENSOR DATA FUSION TECHNIQUE

The coal-rock interface recognition method based on multi-sensor data fusiontechnique is put forward because of the localization of single type sensor recognition method. Themeasuring theory based on multi-sensor data fusion technique is analyzed, and hereby the testplatform of recognition system is manufactured. The advantage of data fusion with the fuzzy neuralnetwork (FNN) technique has been probed. The two-level FNN is constructed and data fusion is carriedout. The experiments show that in various conditions the method can always acquire a much higherrecognition rate than normal ones.

Performance evaluation of minimum quantity lubrication by vege-table oil in terms of cutting force,cutting zone temperature,tool wear,job dimension and surface finish in turning AISI-1060 steel

In all machining processes, tool wear is a natural phenomenon and it leads to tool failure. The growing demands for high productivity of machining need use of high cutting velocity and feed rate. Such machining inherently produces high cutting temperature, which not only reduces tool life but also impairs the product quality. Metal cutting fluid changes the performance of machining operations because of their lubrication, cooling and chip flushing functions, but the use of cutting fluid has become more problematic in terms of both employee health and environmental pollution. The minimization of cutting fluid also leads to economical benefits by way of saving lubricant costs and workpiece/tool/machine cleaning cycle time. The concept of minimum quantity lubrication (MQL) has been suggested since a decade ago as a means of addressing the issues of environmental intru- siveness and occupational hazards associated with the airborne cutting fluid particles on factory shop floors. This paper deals with experimental investigation on the role of MQL by vegetable oil on cutting temperature, tool wear, surface roughness and dimen- sional deviation in turning AISI-1060 steel at industrial speed-feed combinations by uncoated carbide insert. The encouraging results include significant reduction in tool wear rate, dimensional inaccuracy and surface roughness by MQL mainly through reduction in the cutting zone temperature and favorable change in the chip-tool and work-tool interaction.

The Offline Program Profile Lining and Cutting Robot System

The paper introduces a new type of cutting system: the Offline Program Profile Lining and Cutting Robot System (OPPLCRS). The system adopts the offline program technology without teaching. The system can measure and compensate every profile’s deformation automatically, so it is suit to process any batch of profiles, and the order of processing different profiles can be arranged at will. The OPPLCRS, firstly appearing in China, will have wide application in profile cutting fields.

Free-Interface Dual-Compatibility Modal Synthesis Substructure Method in Large-Scale Structures

Free-interface dual-compatibility modal synthesis method(compatibility of both force and displacement on interfaces)is introduced to large-scale civil engineering structure to enhance computation efficiency. The basic equations of the method are first set up, and then the mode cut-off principle and the dividing principle are proposed. MATLAB is used for simulation in different frame structures. The simulation results demonstrate the applicability of this substructure method to civil engineering structures and the correctness of the proposed mode cut-off principle. Studies are also conducted on how to divide the whole structure for better computation efficiency while maintaining better precision. It is observed that the geometry and material properties should be considered, and the synthesis results would be more precise when the inflection points of the mode shapes are taken into consideration. Furthermore, the simulation performed on a large-scale high-rise connected structure further proves the feasibility and efficiency of this modal synthesis method compared with the traditional global method. It is also concluded from the simulation results that the fewer number of DOFs in each substructure will result in better computation efficiency, but too many substructures will be time-consuming due to the tedious synthesis procedures. Moreover, the substructures with free interface will introduce errors and reduce the precision dramatically, which should be avoided.

含挖填界面边坡三维稳定性上限分析

针对工程实践中挖填交界面与边坡坡面走向线斜交的高边坡空间三维稳定分析问题,基于极限分析上限定理,构建拓展的三维牛角状破坏机构,通过引入机构参数挖填界面倾角α突出边坡特性,建立与之对应的功能平衡方程,采用序列二次规划优化算法求解强度折减后的边坡安全系数上限解。在此基础上,计算了宁夏黄土丘陵地区妙岭750kV变电站高边坡以及相关文献中极限状态下边坡稳定性系数γH/c工程案例,并将计算结果与有限元极限分析软件模拟值进行对比分析。结果表明:随着挖填界面倾角α的增大,边坡安全系数Fs上限解和模拟值均减小,两种方法的计算结果相对误差在5.9%以内,且拓展的破坏机构与数值模拟的剪切耗散变形模式基本一致;在极限状态下,拓展机构的上限解和数值模拟结果都十分接近于1.0,二者相对误差未超过8.3%。研究工作为此类高边坡空间稳定分析问题提供了一种简便实用的计算方法。

Analysis and Numerical Simulation of Hydrofracture Crack Propagation in Coal-Rock Bed

In underground coal mines,hydrofracture can cause the increase of breathability in the fractured coal bed.When the hydrofracture crack propagates to the interface between the coal bed and the roof-floor stratum,the crack may enter roof-floor lithology,thus posing a limit on the scope of breathability increase and making it difficult to support the roof and floor board for subsequent coal mining.In this work,a two-dimensional model of coal rock bed that contains hydrofracture crack was constructed.Then an investigation that combines the fracture mechanics and the system of flow and solid in rock failure process analysis(RFPA2D-Flow)were carried out to study the failure mechanism at the interface between rocks and coals,and critical water pressure that hydrofracture crack propagates.The results indicated that the main factors that affect the direction of hydrofracture crack propagation are the angle of intersection between coal-rock interface and horizontal section,horizontal crustal stress difference,tension-shear mixed crack fracture toughness in coal-rock interface and differences in elasticity modulus of coal-rock bed.The possibility of crack directly entering coal-rock interface would increase with the increase in angle of intersection or horizontal crustal stress difference.The trend that crack propagates along the coal-rock interface will become stronger with the decrease of the fracture toughness at the coal-rock interface and the increase of the elasticity modulus difference between the coal bed and the roof strata.The results of this study was to put forward a method of controlling hydrofracture crack,optimize the fracturing well location provides a certain theoretical basis.

适用二维切割体网格的THINC/QQ算法扩展研究

为了扩展基于二次曲面和高斯积分的双曲正切函数界面捕捉算法THINC/QQ的单元适用类型,本文将适用切割表面式非结构单元的THINC/QQ-SF算法原理应用于二维切割体网格。在进行界面重构时,先将带悬挂点的复杂单元虚拟简化为常规的四边形或三角形单元;而在计算流体体积流量时再考虑各单元的真实拓扑结构。针对典型流体体积对流和溃坝算例,本文设计了一系列二维切割体网格,并验证了所用扩展方法的可行性。研究表明:与高分辨率界面捕捉HRIC算法相比,二维THINC/QQ-SF算法的计算精度更高,能有效抑制多相流界面发生大变形时的流体体积数值耗散。

玻璃钢管壁/原油界面特性对高含水原油低温集输的影响

我国大部分油田已进入开采中后期,油井采出液含水率较高,玻璃钢管道因其良好的抗腐蚀性广泛应用于油田地面集输系统。同时,为了节约加热能耗,可采用低温集输工艺输送高含水原油,但可能出现的原油黏附问题严重威胁系统安全。因此,探究玻璃钢管壁/原油界面特性,对揭示高含水原油低温集输黏附机理具有重要意义。基于接触角仪探究了含蜡原油在玻璃钢和不锈钢表面的界面特性。结果表明,在水相中,油滴在不同材质平板的接触角随温度的降低而增大,且油滴在玻璃钢表面的接触角大于在不锈钢表面的接触角,油滴在水相中的界面张力随温度的降低而增大;与不锈钢表面相比,油滴在玻璃钢表面的黏附功较小,油滴之间的内聚功随温度的升高而减小;在集输系统中,凝油不易黏附于玻璃钢管道,玻璃钢管道更有利于低温集输工艺的实施。

山区填挖交界面施工技术研究

针对山区半挖半填路基交界面施工技术开展研究,简述了山区半挖半填路基交界面处易发生的病害类型,并对山区半填半挖交界面处主要病害的特征进行详细分析和阐述,同时,根据大量山区半挖半填路基工程实践经验,提出和总结半填半挖路基施工技术要求、半填半挖路基交界面填料技术以及交界面处理技术要求,为山区半挖半填路基交界面施工和保证其稳定性提供重要的工程指导价值。

南极冰岩界面钻进过程孔斜规律研究及调控装置设计

南极冰层下基岩取心,对于研究南极冰川形成的历程和全球气候变化等方面具有重要的意义。钻遇冰层和岩层的倾斜交界面时,极易发生孔斜,影响基岩取心的质量甚至成败。本文分析了钻头在冰岩界面钻进过程中的受力状态,探究了地层倾角、钻压、转速、机械钻速、单位体积切削功等因素对钻头受力及孔斜规律的影响。最后,基于满眼防斜的原理设计了针对冰岩界面防斜的垂直入岩装置。

保德煤矿智能化掘进工作面建设及应用研究

为了解决保德煤矿生产接续紧张,实现减人增安、降本增效,提高智能化开采水平,根据单位现有的生产掘进模式结合智能化科技应用,研究工作面国产化电控系统,为各种自动化控制功能提供控制接口;通过截割动载荷识别和自适应截割,实现掘锚一体机记忆割煤和自适应割煤;采用自动锚杆支护,实现钻孔、送药、锚固等工序的自动化运行;实现梭车自动化作业以及机尾自动移设;通过掘、支、锚、运一体化数字孪生技术,实现工作面数据在线监测和设备远程集中控制;工作面多机协同控制,实现“智能掘进、少人操作”。通过以上研究对掘锚机、梭车、连运车及胶带机机尾进行智能升级改造,针对性地建设智能掘进系统,从而探索出一条符合保德煤矿自身生产条件的智能化掘进道路。

山区填挖交界面多层加筋技术研究

针对山区半挖半填路基交界面问题开展研究,简述了山区半挖半填路基土工格栅加筋的种类,并对山区半填半挖各类型土工格栅加筋作用和机理进行探究和分析。同时,结合某典型山区半挖半填路基案例建立数值模型探究不同的土工格栅加筋层数、格栅条的铺设间距等对山区填挖交界面的加筋效果,为山区半挖半填路基交界面多层加筋提供重要的工程指导价值。

微纳米气泡与臭氧催化氧化联用技术的应用进展

臭氧催化作为1种高级氧化工业废水处理技术,因其廉价、高效、无二次污染、操作简便等优势被广泛应用于工业废水处理中。在臭氧催化氧化中,常规曝气使臭氧气泡平均粒径在毫米级以上,该种大粒径气泡会直接导致臭氧气泡稳定性差、臭氧利用率及氧化能力降低,而微纳米气泡-臭氧催化氧化联用技术能保证臭氧气泡粒径分布在200 nm~60μm,可延长气泡停留时间、促进臭氧溶解及增强氧化能力。根据微纳米气泡产生的原理,阐述了微纳米气泡产生方法,包括加压减压方式、汽水循环方式、射流曝气方式等。此外,从提高臭氧溶解率和加强臭氧氧化能力2个方面论述了臭氧微纳米气泡的性质,并从难降解工业废水处理、地下水修复、杀菌消毒3个方面剖析了微纳米气泡在臭氧催化氧化中的应用。微纳米气泡-臭氧催化氧化联用技术作为一种绿色环保新兴技术,相较于传统臭氧催化氧化工艺具有明显优势,然而臭氧微纳米气泡作用于目标去除物的传质过程尚不明确,国内生产的微纳米气泡发生器质量还有待改善,需提高纳米级气泡的产出率与质量,并将臭氧微纳米气泡技术与光催化、电催化、超声催化等技术相结合以拓展其应用领域。

基于接口的小型农业作业机模块划分方法

产品模块化设计时模块划分的合理性直接影响实现大规模定制生产的效果。提出了一种通过接口关系进行模块划分的方法,将零件接口关系用模糊隶属度函数进行定量化描述,在模糊图上通过割集的方法实现模块的合理划分。以SF5系列小型农业作业机产品为例,通过模块化设计将不同模块进行组合,可满足农林牧多行业用户的功能需求。

半填半挖路基交接面稳定性分析

分析了交接面对半填半挖路基稳定性的影响因素,在总体上将其归纳为几何特征和物理力学参数两类。研究了交接面的台阶特征、填料物理力学参数的差异性,分析了不平衡推力法在条块划分、计算结果误差方面的不足,阐明了不平衡推力法用来分析半填半挖路基交接面的稳定性的缺陷,推荐以改进的Sarma(MSarma)方法替换。以某公路半填半挖路基交接面分析为基础,将正交试验设计方法、统计方法和MSarma方法结合起来,形成了半填半挖路基交接面稳定性力学机制分析方法。采用该法研究了半填半挖路基交接面3种工况条件下各种因素对路基稳定性系数影响的敏感性排序,前4位依次为黏聚力、内摩擦角、交接面和地基倾角。在研究这4个主要参数与稳定性系数量化关系并比较变化趋势的基础上,为填料、交接面参数及路基形式选择提供了指导原则。

故障树定量分析及其交互方式的实现

在分析制作故障树分析软件原因的基础上,分析了作为交互软件内核的故障树分析理论,详细研究了相应的算法及实现。与此同时,以MATLAB7.0作为软件设计的工具,分析了面向对象的图形用户界面(GUI)设计的功能和特点。进而将主程序和界面程序以控件形式结合,形成了功能较为完备的FTA软件。实际设计和运用表明,基于MATLAB7.0的FTA软件具有界面交互友好、读写格式清晰、显示结果规范的优点。

CrTiAlN镀层对M2基高速钢切削性能的影响

分析了CrTiAlN镀层的组织,研究了CrTiAlN镀层对M2高速钢刀具切削性能的影响．结果表明:CrTiAlN镀层提高了M2基高速钢刀具的切削性能．CrTiAlN镀层具有良好的高温稳定性能,能避免红硬性不足引起的刀具失效;CrTiAlN 镀层与M2基体的结合较强,具有稳定结构,能避免抗压强度下降引起的刀具失效．

SiCw/Al复合材料切削表面层中SiC-Al界面观察(英文)

The SiC-Al interface in the cutting surface layer of the squeeze casting SiCw/Al composite was observed by transaction electron microscope (TEM). The results showed that there was a high density dislocation in the aluminium matrix, and the SiC-Al interfaces were not destroied during the cutting processes. It has been proved that the squeeze casting SiCw/Al composites have high interface bonding strength, so it is necessary to study the interface bonding mechanism of the SiCw/Al composite. TEM observation results showed that at the SiC-Al interface in the squeeze casting SiCw/Al composite, no new phases were observed, and no long distance (more than 50nm) mutual diffusion of Si and Al was found. Further

剪纸艺术形式对室内空间界面设计的启示

剪纸艺术形式对室内空间设计具有较大的借鉴与启示作用,本文从剪纸艺术的吉祥寓意、图底变换、"镂空"视觉效果等方面阐述了其对室内空间界面设计的启示,旨在世界设计潮流中保留本国特色,并从中国剪纸艺术中得到灵感,从而促进本国设计的发展,彰显其中国特色.

刀-屑接触区摩擦润滑的毛细管模型研究

切削时刀-屑接触区为边界摩擦状态,冷却润滑剂难以进入,其作用可用毛细管理论解释。在切削试验与理论分析的基础上,提出了圆锥形毛细管模型。动力学分析结果表明:冷却润滑剂的微粒尺寸越小,冷却润滑效果越好。刀-屑接触面的吸附作用能形成边界润滑膜,圆锥形毛细管能限制冷却润滑剂的渗透深度,负压力可为冷却润滑剂的渗透提供动力。