煤矿井下人员定位系统的研究与实现

针对现有煤矿井下定位系统在井下采取单一的定位方法,进而导致定位成本高、精度过低或过高的问题,提出一种新型的煤矿井下定位系统。将定位环境分为巷道、采空区和硐室3种类型。根据3种定位场合的特点,研究了信标节点的布置方案,并且根据定位要求,在采空区采取RSSI定位中的三边定位算法,在硐室和巷道中采取了RSSI的修正方法,在三边定位算法中加入了质心定位算法,测试数据表明,可以满足定具体环境的定位要求。     

采动过程中微地震定位方法研究

对当前微地震的主要定位方法包括P波定位法、地震波射线法、P波射线传播方向交汇点法等推导的定位公式进行了对比分析,总结了各自优缺点及适用条件。同时在实验室利用预制的混凝土模型,模拟矿山监测环境,采用P波定位法对其模拟定位,定位结果与实际情况进行比较,破裂位置基本吻合(定位精度±1m),表明微地震技术能满足采矿工程中的应用条件。     

差分定位技术在哈尔乌素露天矿中的应用

以哈尔乌素露天矿为背景,基于单站差分的伪距差分技术的技术原理,研究了差分辅助定位系统设计方法,包括差分定位基站位置选择与差分定位系统网络布置,研究了基于差分定位技术的钻机钻孔技术与工程车辆定位技术。差分定位技术提高了哈尔乌素露天煤矿生产效率和安全生产水平。     

阶梯孔零件加工中定位选择对误差的影响

不同的定位方式对工艺质量有相当重要的影响,而基准位移和基准不重合作为产生定位误差的重要因素,在定位方式选择上应优先考虑;以阶梯孔零件加工为载体,建立对比数学模型,采用定位理论分析、实践数据分析、误差改进设计等方法,从误差的来源、影响程度、定位方式选择、误差计算到定位改进对此问题进行探讨,达到降低误差影响,提高工艺质量的目的。     

采动过程中微地震定位方法研究

对当前微地震的主要定位方法包括P波定位法、地震波射线法、P波射线传播方向交汇点法等推导的定位公式进行了对比分析,总结了各自优缺点及适用条件。同时在实验室利用预制的混凝土模型,模拟矿山监测环境,采用P波定位法对其模拟定位,定位结果与实际情况进行比较,破裂位置基本吻合(定位精度±1m),表明微地震技术能满足采矿工程中的应用条件。     

GPS-RTK在地质勘探工程测量中的应用

主要介绍了GPS-RTK技术及其快速静态定位、准动态定位和动态定位三种定位模式,重点对GPS-RTK技术在地质勘探工程测量中的勘探网及控制测量、地形测量、工程点布设、勘探线剖面测量、地质工程点定位测量和物化探测量等应用情况进行了分析.并对GPS-RTK技术应用中的测量误差和精度、基准站和移动站的设置以及数据链通讯和作业半径的确定进行了讨论.     

基于时差定位线性算法和Geigei迭代算法的某铁矿声发射源定位精度分析

时差线性定位算法主要参考时间差时,波速等参数构建线性方程组进行代数方法的求解,该法原理和计算过程都较为简单,但缺点是方程组可能会出现无解导致定位计算失败。Geiger迭代定位算法在选取了合适迭代初值的基础上进行多次迭代,得到定位结果,其在原理上比时差线性定位算法更精确,本文对时差定位中的线性定位和Geiger迭代定位两种算法结合云南某大型铁矿的声发射监测系统监测到的声发射事件进行了分析,通过两种定位算法得到的定位结果误差对比分析来具体说明两种方法对于工程实际的适用性和精确度。     

定位误差的分析及计算

介绍了两种定位基准情况下定位误差的计算方法     

井下GRPM定位研究与地磁匹配的仿真试验

针对无电、无网络情况下井下人员逃生定位和救援导航的难题,架构了井下地磁与RFID 射频结合的井下定位方法GRPM(Geomagnetic and Radio Positioning Method)。GRPM采用射频初定位、地磁特征精定位的主动定位模式,适合应急避险与救援定位需求。根据井下高精度地磁测量数据和井下地磁“日变”规律,分析了井下巷道地磁数据具有带状连续、区域易突变的数据特点。采用了分段线性法、最近邻域法和三次曲面法插值方法和MSD,HD和NPROD三种匹配准则,开展了地磁基准构建和地磁匹配定位的仿真实验。实验结果表明:分段线性插值法适合小区域巷道地磁基准建立,拟合快速,精度较高,符合井下巷道磁场分布的收敛性。NPROD定位匹配模型适合井下人员动态行走定位,匹配速度快,达到2/3格网精度,满足精确定位要求。     

可见光定位技术在矿井人员定位系统中的应用研究

矿井人员位置监测系统是国家要求装备的煤矿安全避险六大系统之一,在煤矿安全生产、事故应急救援和事故调查中发挥着重要作用。可见光定位技术因其安全性高、成本低、绿色节能等优势成为极具潜力的矿井定位技术之一。总结了矿井常用无线定位技术的特点,如基于射频标签识别、Wi-Fi、ZigBee、超宽带、5G的室内定位技术,提出采用可见光定位技术实现矿井人员定位的方法。总结了常用可见光定位算法,讨论了几种适合矿井巷道的可见光定位系统,定位平均误差均低于10 cm,成像定位系统对光强变化不敏感,受环境影响小,定位效果更稳定。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

2014 second batch of rare earth quota released

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矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586