基于Spark平台的微震信号鉴别方法

凿岩爆破是金属矿山开采过程中不可避免的环节,爆破扰动产生的微震信号会对岩体损伤微震信号的分析造成干扰.为了避免爆破扰动对微震监测的干扰,实现岩体损伤微震信号与爆破微震信号的快速鉴别,基于Spark平台的Fisher分类算法建立了微震信号智能识别算法,实现了岩体损伤和爆破事件的自动区分.经过测试,该算法鉴别信号的正确率稳...     

新旧HP—Nb炉管焊接后的剩余寿命

制氢转化炉炉管局部发生失效后,采用局部更换炉管失效段的方法可以延长整根炉管的使用寿命。采用微观组织分级法、硬度测量法以及Larson-Miller参数法对某厂新旧HP-Nb炉管焊接后的剩余寿命进行综合评价,结果表明新旧炉管焊接后的剩余寿命约为45000h,蠕变断裂将发生在旧炉管的母材上。     

基于VMD的TFPF微震数据随机噪声去除方法应用研究

由于金属矿山复杂的环境条件,微震监测方法所采集的微震数据中含 有大量的随机噪声,导致有效信 号到时拾取准确性的降低,将严重响应微震源定位的准确性。 因此,本文提 出了一种基于变分模态分解( VMD)的时 频峰值滤波(TFPF)方法,进行微震数据随机噪声去除的应用研究。 该方法 将微震数据利用 VMD 分解成若干个主频 和带宽不同的信号分量,对不同的信号分量选取对应窗长进行 TFPF 随机噪 声去除处理,再进行信号重构,以达到压 制随机噪声的目的。 通过理论和实际数据的测试,验证了 VMD-TFPF 方法 去除随机噪声的有效性与优越性。 随机噪 声的有效去除,对提高微震数据处理的精度具有重要意义。     

太阳电池最大功率及其跟踪模式

根据太阳电池电流方程及输出功率极值条件,在温度保持不变时,可建立最大功率方程,由此可在伏安特性坐标系内绘制大范围光照变化时最大功率的轨迹线,发现其呈现为S形状。据此提出三种最大功率的跟踪模式:(1)恒载跟踪;(2)恒压跟踪;(3)计算跟踪。其中恒载跟踪适用极低光照和极强光照,恒压跟踪适合于中等光照,计算跟踪适合于恒压跟踪向恒载跟踪的过渡光强。计算跟踪是本文给出的一种最大功率电压联立求解的计算方法。     

含缺陷球罐的安全评定

在数值模拟计算含缺陷球罐应力场的基础上,对含缺陷球罐在工作压力和超压两种工况下进行了断裂安全评定和强度校核。评定结果表明,含缺陷球罐在正常使用及超压工况下是安全的,同时对其继续使用提出了一些建议。     

The optical-electrical properties of doped β-FeSi2

By using the pseudo-potential plane-wave method of first principles based on the density function theory,the geometrical,electronic structures and optical properties of FeSi1.875M0.125(MDB,N,Al,P) were calculated and analyzed.The calculated structural parameters depend strongly on the kinds of dopants and sites.The total energy calculations for substitution of dopants at the SiI and the SiII sites revealed that Al and P prefer the SiI sites,whereas B and N prefer the SiII sites.The calculations predict that B- and Al-doped β-FeSi2 show p-type conduction,while N- and P-doped show n-type.Optical property calculations show that N-doping has little influence on the complex dielectric function of β-FeSi2; B-,N-,Al- and P-doping can enhance the electronic transition,refractive index,and reflection effect in the low-energy range,and weaken the reflection effect at the max peak of reflectivity.These results can offer theoretical guidance for the design and application of optoelectronic material β-FeSi2.     

高温高压条件下不锈钢的氢损伤

综述了高温高压条件下氢致不锈钢损伤的研究进展情况,重点介绍了不锈钢力学性能和微观结构的变化,并就压力和温度对氢损伤敏感性影响作了简单的讨论。     

A new approach to regulate the photoelectric properties of two-dimensional SiC materials:first-principles calculation on B-N co-doping

This paper describes a new approach to regulate the photoelectric properties of two-dimensional SiC materials. The first-principles pseudo-potential plane wave method is used to calculate the geometric structure, electronic structure and optical properties of two-dimensional (2D) SiC co-doped by the adjacent elements of C-Si (such as B and N). The results show that:after B-N co-doping, the supercell lattices of 2D SiC are observed obviously deformation near the doped atoms. Meanwhile, the band structures of 2D SiC co-doped by B-N become rich. As the impurity level enters the forbidden band, the band gap decreases, and the distribution of density of states near the Fermi level changes accordingly. The calculation of optical properties shows that the ability to absorb electromagnetic waves of 2D SiC has been enhanced obviously in the low energy range after B-N co-doping. The reason is originated from the transition of the 2p state of B and N. At the same time, the static dielectric constant increases and the peak of reflectivity decreases. The above results indicate that the optoelectronic properties of 2D SiC can be modulated by co-doping B-N.     

弓长岭露天铁矿浅层采空区稳定性数值模拟

由于历史原因，弓长岭露天铁矿周边地方小矿点不规范乱采乱挖，导致在独木采区形成了大量的浅层采空区，迫于生产需求，需要对独木采区小北沟空区进行爆破处理。为了保障牙轮钻设备及人员安全，需要对空区的稳定性进行评价。考虑到弓长岭露天矿采空区地质赋存条件和围岩稳固性等特征，运用FLAC3D数值计算，开展了小北沟空区静力学计算和空区上方承载牙轮钻机的计算分析。研究表明：采空区形成后，在顶板处产生的最大压应力值为2 MPa，在顶板处产生的最大拉应力值为0.25 MPa，产生的压应力和拉应力均不是很大；地表12个监测点显示，地表最大垂直位移值不超过10 mm；在地表危险区域1施加牙轮钻机等效载荷，产生最大的垂直位移约为0.56 mm，在地表危险区域2施加牙轮钻机等效载荷，产生最大的垂直位移约为0.48 mm，牙轮钻机不会对地表沉降产生明显影响。