During seismic data acquisition, a high-sensitivity geophone with a high inherent frequency can increase high frequency energy by suppressing low frequency signals. This could cause a worse response at low frequencies...During seismic data acquisition, a high-sensitivity geophone with a high inherent frequency can increase high frequency energy by suppressing low frequency signals. This could cause a worse response at low frequencies. If the advantages of high-sensitivity data and conventional data are combined, the effective bandwidth will be broadened. Considering this, we propose a partial frequency band match filtering method which can combine the advantages of both high frequency and conventional frequency ranges. By introducing Ricker wavelets with different dominant frequencies and amplitudes, we established a theoretical model which possesses characteristics of both types of seismic data and demonstrates the feasibility of the partial frequency band match filtering method. A test using single shot records shows the effectiveness of this method for widening the effective frequency band.展开更多
温度是影响材料力学性能的重要因素之一,准确测量器件温度是认识材料在应力作用下其力学性能演变以及评估设备健康状态和寿命的重要方式。面向功率器件开关过程中焊接界面快速温变测量的需求,传统方法存在时间分辨能力不足、难以测量瞬...温度是影响材料力学性能的重要因素之一,准确测量器件温度是认识材料在应力作用下其力学性能演变以及评估设备健康状态和寿命的重要方式。面向功率器件开关过程中焊接界面快速温变测量的需求,传统方法存在时间分辨能力不足、难以测量瞬态温度的问题。文中基于激光诱导元素特征谱线强度与温度的密切相关性,提出了一种微秒量级时间分辨能力的表面温度测量方法,并建立了样品表面温度与光谱特性之间的定量关系。研究结果表明,物质表面温度提升导致激光诱导等离子体光谱强度和信噪比增强,且增强效果受到光谱采集延时和门宽影响。采用反向传播-人工神经网络(back propagation-artificial neural network,BP-ANN)和偏最小二乘(partial least squares,PLS)法对表面温度与光谱特性关系定量拟合并校准,拟合模型线性相关性拟合度指标均大于0.99。BP-ANN拟合模型的拟合偏差更小,其均方根误差(root mean squared error,RMSE)为2.582,正确率为98.3%。该方法为物体瞬态温度测量提供了一种有效手段,对功率器件焊接界面健康状态的评估给予了有力支撑。展开更多
基金financially supported by the National Natural Science Foundation of China(No.41104072)College Students Science and Technology Innovation Activity Plan in Zhejiang Province(No. 2012R401214)
文摘During seismic data acquisition, a high-sensitivity geophone with a high inherent frequency can increase high frequency energy by suppressing low frequency signals. This could cause a worse response at low frequencies. If the advantages of high-sensitivity data and conventional data are combined, the effective bandwidth will be broadened. Considering this, we propose a partial frequency band match filtering method which can combine the advantages of both high frequency and conventional frequency ranges. By introducing Ricker wavelets with different dominant frequencies and amplitudes, we established a theoretical model which possesses characteristics of both types of seismic data and demonstrates the feasibility of the partial frequency band match filtering method. A test using single shot records shows the effectiveness of this method for widening the effective frequency band.
文摘温度是影响材料力学性能的重要因素之一,准确测量器件温度是认识材料在应力作用下其力学性能演变以及评估设备健康状态和寿命的重要方式。面向功率器件开关过程中焊接界面快速温变测量的需求,传统方法存在时间分辨能力不足、难以测量瞬态温度的问题。文中基于激光诱导元素特征谱线强度与温度的密切相关性,提出了一种微秒量级时间分辨能力的表面温度测量方法,并建立了样品表面温度与光谱特性之间的定量关系。研究结果表明,物质表面温度提升导致激光诱导等离子体光谱强度和信噪比增强,且增强效果受到光谱采集延时和门宽影响。采用反向传播-人工神经网络(back propagation-artificial neural network,BP-ANN)和偏最小二乘(partial least squares,PLS)法对表面温度与光谱特性关系定量拟合并校准,拟合模型线性相关性拟合度指标均大于0.99。BP-ANN拟合模型的拟合偏差更小,其均方根误差(root mean squared error,RMSE)为2.582,正确率为98.3%。该方法为物体瞬态温度测量提供了一种有效手段,对功率器件焊接界面健康状态的评估给予了有力支撑。
基金国家重点基础研究发展计划项目(973计划)(2014CB-239506)国家电网公司科技项目(52020114026L)+1 种基金Project Supported by the National Basic Research Program(973 Program)(2014CB239506)Science and Technology Project of State Grid Corporation of China(52020114026L)
