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121.
Juray De Wilde Denis Constales Geraldine J. Heynderickx Guy B. Marin 《International Journal of Multiphase Flow》2007
The propagation speeds of linear waves in gas–solid suspensions depend strongly on the solids volume fraction and the wave frequency. The latter is due to gas–solid momentum transfer and allows a simple test on filtered gas–solid momentum transfer models. Such models may predict linear wave propagation speeds different from those obtained with the non-filtered model at wave frequencies higher than the filter frequency, but not at wave frequencies lower than the filter frequency. 相似文献
122.
一种新型温度自补偿高灵敏度折射率计 总被引:7,自引:0,他引:7
基于高频CO2激光脉冲写入的新型超长周期光纤光栅(ULPFG),提出了一种可实现温度自补偿的新型高灵敏度折射率计。理论与实验表明,新型超长周期光纤光栅不同闪耀阶次谐振峰对外界折射率与温度变化的灵敏度各自不同,特别的是,该光栅存在对外界折变不敏感的谐振峰,测量中除了可以利用该峰实现温度同时测量外,还可以补偿另一个测量折变的谐振峰因温度变化带来的测量误差。该折射率计具有制作简单、成本低、强度好,灵敏度高等优点,当外界折射率在1.43~1.45范围内变化时,其折射率测量灵敏度可达每单位折射率240 nm,在实际工业应用中具有较大的潜在实用价值。 相似文献
123.
124.
《Surface and interface analysis : SIA》2006,38(1):19-24
We have been developing a new analytical transmission electron microscope (TEM), called a coincidence TEM, which in principle enables elemental mapping images to be observed at a high signal‐to‐noise (S/N) ratio under very low dose radiation conditions. In this paper, we report the development of a coincidence TEM with a digital waveform measuring system for obtaining a coincidence elemental mapping image. In this system, analog signals detected by a Si(Li) detector and a multianode, position‐sensitive photomultiplier (PSPM) are continuously converted into 12‐bit digital waveform data at a rate of 100 MHz, and transferred to a PC. From the transferred digital waveform data, information on X‐ray photon energy, electron incident position, and detection times of both X rays and electrons are calculated by digital waveform measurement, which lead to the observation of a successful coincidence elemental mapping image. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
125.
In this paper, a quantum secure direct communication protocol using ensembles with the same density matrix is proposed. The two communication parties can realize the message transmission using this method through a quantum channel, each bit of information can be transmitted using an ensemble and read out through global measurement.The eavesdropping behavior can be detected through the channel diagnoses. 相似文献
126.
叙述一种新的光电复合测量技术,它集CCD摄像显示,微机信息采集与处理,光不投影放大,显微镜目视判读为一体,可对微粒大小及其空间分布实行多通道测量,观察和分析。 相似文献
127.
128.
郑洪 《浙江大学学报(理学版)》1996,23(4):342-347
本文介绍了一种钢卷尺刻度在线测量系统 ,它采用了高速摄像及计算机数据处理技术 ,文章阐述了系统的非接触动态测量原理 ,描述了光电信号的处理方法 . 相似文献
129.
According to Bell's theorem, the degree of correlation between spatially separated measurements on a quantum system is limited by certain inequalities if one assumes the condition of locality. Quantum mechanics predicts that this limit can be exceeded, making it nonlocal. We analyse the effect of an environment modelled by a fluctuating magnetic field on the quantum correlations in an EPR singlet as seen in the Bell inequality. We show that in an EPR setup, the system goes from the usual ‘violation’ of Bell's inequality to a ‘non-violation’ for times larger than a characteristic time scale which is related to the parameters of the fluctuating field. We also look at these inequalities as a function of the spatial separation between the EPR pair. 相似文献
130.
The purpose of this paper is to analyze the convergence of interval-type algorithms for solving the generalized fractional program. They are characterized by an interval [LB
k
, UB
k
] including*, and the length of the interval is reduced at each iteration. A closer analysis of the bounds LB
k
and UB
k
allows to modify slightly the best known interval-type algorithm NEWMODM accordingly to prove its convergence and derive convergence rates similar to those for a Dinkelbach-type algorithm MAXMODM under the same conditions. Numerical results in the linear case indicate that the modifications to get convergence results are not obtained at the expense of the numerical efficiency since the modified version BFII is as efficient as NEWMODM and more efficient than MAXMODM.This research was supported by NSERC (Grant A8312) and FCAR (Grant 0899). 相似文献