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991.
The display image of a PC can be reconstructed by using the conducted emission on the PC's network cable. The relevant signals which be used to reconstruct the original image are coupling from the radiation of the switching of red, green, blue (RGB) signals in PC. These pertinent signals are partly contained in the frequency region higher than 30 MHz in the conducted emission. From these findings, the near-field coupling principle from PC to the network cable is analyzed firstly. And then, a multi-conductor transmission model for the RGB signals which transmit in the network cable is proposed. In addition, the maximum safe distance is estimated by using this model. In order to check the validity of the estimating distance, the eavesdropping experiment is carried out to reconstruct the original display image. The results demonstrate that the blurred display image can be retrieved at the place of 29.5 m. 相似文献
992.
孙笑雨 《沈阳工程学院学报(自然科学版)》2001,(1)
介绍了一种新型的模拟电网噪声的设备 ,该设备性能可靠、体积小、操作方便 ,能模拟产生规定幅值和脉宽的电网噪声 ,适合现场应用。 相似文献
993.
994.
针对链条炉排牵引力设计时缺乏可靠依据、制造时缺乏定量检测的现状,采用转矩测量钳和电磁加载器,研制了炉排牵引力及其调速机动态转矩测试系统,可满足其从静止到高速的宽调速范围的转矩测量。 相似文献
995.
电磁感应加热器在吹膜机组上的应用 总被引:1,自引:0,他引:1
电磁感应加热器具有加热迅速、温度控制实时准确等特点,应用于塑料吹膜机组上,不但能改变传统电阻丝加热方式工艺落后、高耗能等现状,而且还能使吹膜机组料筒树脂易于塑化,使薄膜产品性能明显提高;同时电磁感应加热器也具有使用寿命长、维护简单、功率大、安全可靠的特点,起到了节约电能和降低环境温度的作用。 相似文献
996.
Jungho Kim H. Zhang G. D. Gu Young-June Kim 《Journal of Superconductivity and Novel Magnetism》2009,22(3):251-254
We report x-ray scattering study of charge density wave (stripe) order in La2−x
Ba
x
CuO4 (LBCO) and La1.6−x
Nd0.4Sr
x
CuO4 (LNSCO). The doping dependence of the charge stripe ordering temperature and the low-temperature correlation length is compared
with the bulk superconducting transition temperature. We find that the charge stripe ordering temperature and correlation
length are quite different in these two families of cuprates, while there seems to be inverse correlation between the bulk
superconducting temperature and the charge stripe correlation length. 相似文献
997.
Temporal fluctuations of the speckle pattern formed upon backscattering of a laser beam from an interface between gold and nonlinear polymer film have been observed as a function of optical power. The instability can be explained by coupling of laser light to surface plasmons and other guided modes, which experience multiple scattering while propagating in the film along the interface. The speckle pattern produced in this process is extremely sensitive to fluctuations of the scattering potential near the interface. 相似文献
998.
The carrier cooling and the carrier relaxation of an InN thin film illuminated with two excitation energies of 1.53 and 3.06 eV were studied by an ultrafast time-resolved photoluminescence upconversion apparatus. The hot phonon effect could be accounted for longer effective phonon emission times as compared to the theoretical prediction. The rise time and the LO phonon emission time for 3.06 eV excitation were much smaller than those for 1.53 eV excitation. These differences were attributed to the intervalley scattering between the Γ1 and Γ3 valleys in InN when carriers were excited with the energy of 3.06 eV. The intervalley scattering times of 250 fs and 2 ps were estimated for the intervalley scattering from the Γ1 to Γ3 valley and the reversed scattering process, respectively. 相似文献
999.
F. Cser 《应用聚合物科学杂志》2001,80(12):2300-2308
Lorentz correction is used to correct the intensities of X‐ray scattering of single crystal diffractometry in order to recalculate intensities to obtain structure factors. This correction reduces the intensities to zero at zero diffraction angle. Small angle scattering is used to study the dimensions of heterogeneities in polymeric materials. The scattering intensities near to zero scattering angle originate partly from periodic systems (reciprocal lattice) and partly from dispersed particle systems. Periodic systems should result in individual Gaussian or Lorentzian peaks with the position of a peak maximum depending on the length of the periodicity. Particle scattering results in a Gaussian peak centred at zero scattering angle. The effect of the Lorentz correction on the interpretation of small angle X‐ray scattering data is shown in the case of some semicrystalline polyethylenes (high density, linear low density, and low molecular weight waxy polyethylenes). The data are compared with those for amorphous block copolymers (styrene/butadiene) in which there is a periodic system with homogeneous lamellar thickness. Lorentz correction destroys the characteristics of the particle scattering and can be applied only for periodic systems. It should not be used to produce a peak on scattering data which does not show periodicity (peaks) without correction. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2300–2308, 2001 相似文献
1000.