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根据火山岩的岩性和电性特征,对南堡凹陷火山岩地层做了对比和划分.以岩流组作为基本地层划分单元,该地区以NP1-18井作为标准共划分出了6个岩流组,以此作为基础进行对比.结果表明,该地区爆发相发育于火山口相和近火山口相.整个地区广泛发育溢流相,火山构造类型属于盾状火山. 相似文献
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对SiC纤维的直流电阻加热CVD工艺进行了研究,实验采用将两种硅烷的比例混合液体通过液体流量计计量供液并即时完全汽化后与氢气混合输入到反应管并在水冷水银封入气口通入顶吹氢的供气方案,从而简化了工艺并解决了反应气体冷凝问题.在CVD工艺研究中发现影响纤维沉积质量的因素主要有沉积温度、反应气体组分及流量、走丝速度等工艺参数,此外还发现直流电阻加热CVD工艺中,反应管前后存在约200℃的温差,采用双沉积室工艺可减缓温差.在一定的沉积参数下,可沉积出直径60~100μm、抗拉强度3100~4080MPa的SiC纤维. 相似文献
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将自适应核估计的ICA算法应用于DS-CDMA系统的多用户检测中,在没有关于混叠信号的分布假设时,根据信号的统计特性自动估计评价函数,采用自适应核密度估计ICA算法检测器的输出初始化独立分量分析的迭代,对任意混叠信号进行盲分离。通过与传统匹配滤波检测和ICA后处理匹配滤波检测进行仿真比对,证明了该算法在DS-CDMA多用户检测中的可行性和优越性。 相似文献
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A relatively perfect coalmine fire risk-evaluating and order-arranging model that includes sixteen influential factors was
established according to the statistical information of the fully mechanized coalface ground on the uncertainty measure theory.
Then the single-index measure function of sixteen influential factors and the calculation method of computing the index weight
ground on entropy theory were respectively established. The value assignment of sixteen influential factors was carried out
by the qualitative analysis and observational data, respectively, in succession. The sequence of fire danger class of four
experimental coalfaces could be obtained by the computational aids of Matlab according to the confidence level criterion.
Some conclusions that the fire danger class of the No.1, No.2 and No.3 coalface belongs to high criticality can be obtained.
But the fire danger class of the No.4 coalface belongs to higher criticality. The fire danger class of the No.4 coalface is
more than that of the No.2 coalface. The fire danger class of the No.2 coalface is more than that of the No.1 coalface. Finally,
the fire danger class of the No.1 coalface is more than that of the No.3 coalface. 相似文献
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运用FEM\BEM声振耦合计算方法分析叶片出口角对离心泵在水动力激励下泵壳振动辐射噪声影响。采用大涡模拟方法模拟离心泵内部瞬态流场,获得蜗壳壁面偶极子声源;对泵壳体结构进行模态分析获得结构模态响应;利用LMS Virtual Lab间接边界元IBEM声振耦合模块计算非定常流动引起的离心泵内部噪声,并与实验数据对比,验证基于LES、声振耦合的噪声数值模拟方法可行性。计算离心泵外场噪声及声辐射,研究叶片出口角度对离心泵外场噪声辐射影响。结果表明,离心泵叶片通过频率BPF处的辐射声功率随叶片出口角的增大而增大;外场噪声声压级指向性分布显示叶片出口角存在合适范围,使泵在小流量工况运行时噪声较小。 相似文献
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