Phase-change Ge8Sb92 films were deposited on the varied thermal-conductivity substrates by radio frequency sputtering and their crystallization behavior was investigated. Situ sheet resistance measurement and the X-ray diffraction spectra show a double stage phase transitions of Ge8Sb92 films on the low thermal-conductivity substrates while a single stage phase transition on the high ones with the increasing heating temperature. The first-stage phase transition is amorphous-to-crystalline transition and the second-stage phase transition is partial-to-complete crystalline transition. The results provide experimental basis for the optimization of Ge8Sb92 phase-change memory and the possibility application in three-level electrical storage with single layer GeSb-type phase-change materials.

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Disturbance or corresponding errors of the transmission of information affect the ability of error detection. The chaotic encryption system prevents errors and secures the transmission system safely. The security assures by updating chaotic signals with the parameters of the chaotic circuits which are frequently changed. The data decipher and the encryption by the chaotic signaling system renews and changes the initial condition of a chaotic electric circuit. When most of the decimal portions are less than the threshold, the transmission is accepted, and all the noninteger numbers are rounded to their nearest integers. The criterion allows the error-detection function in the security system that is proposed in this paper. The chaotic encryption system for information is applied to public channels by the authorized individual. Three pictorial examples transmitted in the proposed system successfully demonstrate the security and performance. The new system provides high efficiency in the satellite communication network.

This paper investigates the spatial distributions of electron beam-evaporated atoms and electron beam-induced plasma in the coating process. The materials evaporated by electron beams first form vapour and then a little of plasma is generated in the vapour. The spatial distributions of electron beam-induced atoms and plasma play an important role on the coating uniformity of composition and thickness. The radial distribution of coating deposition thickness of electron beam-evaporated atoms predicted by this study agrees with the available experimental data. The predicted distribution of ion density in the electron beam-induced plasma agrees with the available measured data. The results reveal that the normalized coating thicknesses at the divergence angle of 6 and 14 degrees of vapor source, respectively, are 0.8 and 0.2 of these at divergence angle of 0 degree of vapor source for titanium and aluminum evaporated separately. The similar tendency for the decreasing coating thickness with the radial distance is also obtained for the co-evaporation of aluminum, titanium, and copper. High rotation rate of substrate of vapor source leads to the small deposition rate. Most ions in the electron beam-induced plasma are attracted by electrons of the electon beam and are located at the neighbourhood of the beam region. Therefore, the ion and ion-attracted electron densities rapidly decrease with the increasing radial distance from the electron beam.

Theoretical analysis and a laboratory experiment were carried out to validate a gradient wind balance (GWB) vortex model by simulating hurricane-like cyclonic motion in a rotating tank with a gently sloping bottom. The analysis clarified the effects of the motion on the conservation of potential vorticity of shallow water. The effects include the topography of the sloping bottom, vortex depression, and parabolic-free-surface deformation. The velocity distribution of the vortex was identified by measuring the vortex depression with a vertical laser light sheet and fitting it with the GWB model. The result provides a clear view of the entire vortex structure to understand vortices with large Rossby numbers in geophysical flows.