灰色聚类分析在金属矿山井下作业环境评价中的应用

结合某金矿的实际情况,从人的生理、心理状态和工作效率等角度对金属矿山井下作业环境进行聚类分析。确定了井下作业环境的三种聚类对象的灰类,确定了不同灰类的白化函数,标定了灰色聚类权,并计算出聚类系数,建立了不同作业环境的评价标准,为进一步改善井下作业环境,保障工人的生命安全和身体健康提供了科学依据。     

综采工作面环境状况灰色熵权聚类分析

基于灰色系统理论建立了综采工作面作业环境聚类指标体系。从人对作业环境的适应度出发,确定不同作业环境灰类的灰数,从而给出不同灰类的白化函数。利用现场实测环境参数,根据灰色熵权分析给出各指标信息熵,计算出各指标的聚类权,最后计算出各对象对应的聚类系数,确立了作业环境状况。     

灰色聚类评估模型在矿井通风系统中的应用

利用灰色系统理论中的灰色聚类法对矿井通风系统的方案进行了聚类分析,通过确定不同灰类的白化函数和标定灰色聚类权,计算出了聚类系数,得出了矿井通风系统的决策方案。该方法为矿井通风系统方案的优选提供了科学依据。     

灰色聚类与铀矿井通风系统合理性的综合评判

灰色聚类,即区分聚类元素在聚类指标下的所属类别。铀矿井通风系统合理性的综合评判是一个外延确定而内涵不确定的问题,它属于灰色系统的范畴,该文提出了应用灰色聚类评判铀矿井通风系统合理的一种方法,并用灰这种方法对我矿某矿井调整前后的通风系统合理性进行评判。     

灰色聚类与铀矿井通风系统合理性的综合评判

灰色聚类,即区分聚类元素在聚类指标下的所属类别,铀矿井通风系统合理性的综合评判是一个外延确定而内涵不确定的问题,它属于灰色系统的范畴,本文提出了应用灰色聚类评判铀矿井通风系统合理性的一种方法,并用灰这种方法对我矿某矿井调整前后的通风系统合理性进行评判。     

基于灰色聚类分析的矿山环境质量评价

在灰色聚类分析中,把山西省矿区环境质量作为灰色系统进行研究,利用灰色聚类分析方法对山西省矿区环境质量进行评价。为定量评估研究区矿区环境质量,以国家环境质量标准为依据,以矿山环境11个主要污染物为评价指标,对2012年12个监测点的环境质量监测数据建立了灰色聚类评价模型。在对数据样本进行预处理之前,需采用平均标准化方法对原始样本数据进行无量纲化。通过建立灰类的三角形白化权函数计算实测值的灰类隶属度,采用临界值倒数法得到不同污染因子的危害度,最后对样本数据进行灰色综合聚类评价,并基于ARCGIS平台直观地显示矿山环境质量总体情况。数值结果表明了该方法的合理性和有效性。该研究成果为矿山环境评价提供一条新途径,同时可以在非煤矿山环境评价中进行推广应用。     

物元分析理论在矿井安全评价中的应用

矿井安全状况的好坏受到诸多定量和非定量因素的影响，将物元分析理论和灰色聚类理论相结合，建立了一种新的安全评价分析模型，并利用关联函数值的大小来衡量评价因子与灰类集合的关系，从而使识别方法更为精细化。并且该方法对建模样本的数目没有限制，计算过程简单，实际运用效果较好。     

煤矿瓦斯煤尘爆炸危险源灰色聚类评估

应用安全系统工程和层次分析方法,以人—机—环境—管理4个方面为准则对煤矿瓦斯煤尘爆炸事故危险源进行定性分析。通过两两比较评分准则,借助Mtalab计算各指标的权重。建立基于中心点三角白化权函数的瓦斯煤尘爆炸危险源灰色聚类评估体系,计算各评估指标的灰色聚类系数,确定各准则层所属灰类,从而准确分析煤矿所需整改方向,确保煤矿安全生产。     

煤矿瓦斯爆炸事故演化危险性评价的AHP-GT模型及应用

分析了传统瓦斯危险性评价方法与模型存在的问题,通过对煤矿瓦斯爆炸“人-机-环境-管理”复杂非线性系统分析,建立生产人员素质因素、生产装备因素、环境条件因素、安全管理因素等4个大类和27个小类的危险性评价指标体系。在层次分析法和灰色聚类法等研究基础上,构建了煤矿瓦斯爆炸事故演化危险性评价的非线性多层次灰色评价模型(AHP-GT),确定了评价模型中评价灰类的等级数、灰数及白化权函数,根据评价灰类及白化权函数的非线性,修订了评价目标综合评价等级标准。给出了评价实例,评价结果符合实际。     

基于灰色聚类-IAHP的顶板事故风险评估

为评估顶板事故风险,建立灰色聚类-IAHP风险评价模型,使用区间层次分析法(IAHP)构建评估对象层次结构体系,利用区间数特征根法求得指标权向量,利用灰色聚类法计算出事故风险的综合评价值。评估实例表明,灰色聚类-IAHP评价模型是一种简单实用、操作性较强的风险评估方法,可为顶板事故预防提供参考。     

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

正~~     

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