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Describes a practical application of the line-sampling multiframe stroboscopic technique for dynamic observation of magnetic domain in grain-oriented (GO) silicon (Si) steels in practical use. Diagram of the multiframe stroboscopic observation system; Information on the stroboscopic images.

Hunt’s equation provides a simple means of estimating the runup of breaking waves. However, breaking waves also induce setup on a slope. A modification to Hunt’s equation is advocated which accounts for the presence of wave setup. Support for the modification is provided by data from model tests involving random waves approaching smooth, impermeable slopes of 1:5, 1:10, 1:20, and 1:30. Coefficients to be used in the modified equation are given which allow the significant runup and other characteristic values to be estimated. [ABSTRACT FROM AUTHOR]

Low temperature fabrication of microcrystalline silicon solar cells was studied. It was found that reasonable performance is available even limiting substrate temperature at 100°C. Applying this technique to thermoplastic polymer substrates, a conversion efficiency of 6% was achieved. [Copyright &y& Elsevier]

Detailed operations of the apparatus for the stroboscopic observation of periodic phenomena at the region of line frequencies, such as the magnetic domain response, under the scanning electron microscopy are described in this paper. To achieve the stroboscopic observation at such low frequencies, a new line-sampling technique has been introduced instead of the conventional point-sampling method. In addition to the line-sampling stroboscopy, a multiframe operation is also introduced to display the stroboscopic images of different phase values simultaneously. These operations are simply realized by applying the raster separation and the blanking on the display monitor scope under the multiple line-sampling during the one-drive period. To demonstrate the ability of this simple apparatus, some results of the stroboscopic observation of magnetic domains in an Fe–Si sample under a 60-Hz drive field are also presented in this paper. [ABSTRACT FROM AUTHOR]

The recently developed dynamic observation technique of R. Shimizu and T. Ikuta [Appl. Phys. Lett. 44, 811 (1984)] for scanning electron microscopy, ‘‘line-sampling stroboscopy,’’ was used for the observation of magnetic domains in an amorphous ferromagnetic ribbon. The image-processing technique introduced turned out to be very useful, allowing the behavior of domain walls, which is often obscured by topological contrast, to be clearly observed. [ABSTRACT FROM AUTHOR]

Zheng, J.-H., Jeng, D.-S. and Mase, H., 2007. Sandy beach profile response to sloping seawalls: an experimental study. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 334 – 337. Gold Coast, Australia, ISSN 0749.0208. Seawalls are commonly used as a tool for coastal defence worldwide. Most previous studies have considered the case of vertical seawalls and descriptions of existing seawalls, rather than the influence of different designs of sloping seawalls on beach erosion. In this study, laboratory investigations of an undistorted moveable bed model were conducted to determine the resulting beach profile of artificial sandy beaches. In the experiments, three different sloping seawalls were considered under erosive wave conditions with a 50-year return period. The coast of Northern Jiangsu Province, China, is used as a case study. To simulate natural conditions, similarity criteria are developed assuming that the energy dissipation per unit volume along the beach profile is uniform and that the wave properties can be properly scaled by Froude criteria. Field surveys of beach profile changes due to the storm surge induced by Typhoon 9711 were taken to validate the experimental model and good agreements were attained. Spatial profile configurations were studied by examining dominant profile features such as the break point bar and the scour trough on the seawall-backed profiles. Experimental results provided a reference for the maintenance of artificial sandy beaches and the design of seawalls on the coast of Northern Jiangsu Province, China. [ABSTRACT FROM AUTHOR]

A novel scheme of the plasma-based ion implantation (PBII), the positive pulse bias (PPB) method has been proposed, in which a workpiece to be treated is at the ground potential while the plasma surrounding it is biased to a positive high voltage; thus the ion sheath same as the one in the conventional negative pulse bias (NPB) method is formed on the workpiece. Principal merit of the PPB method over the NPB method is that it possesses a mechanism of suppressing X-rays from the wall by impact of secondary electrons and it enables to manipulate the workpiece during PBII processing. The latter merit will serve to realize an efficient continuous processing system. The principle of the PPB method is discussed based on the asymmetric double probe theory and results of the proof-of-principle experiment are presented. [Copyright &y& Elsevier]

Geometrical effects of a three-dimensional workpiece on the plasma-based ion implantation have been studied using trench-shape and L-shape workpieces. Temporal and spatial evolution of the sheath and the ion flux on the workpiece are measured for a negative voltage pulse of −1.8 to −7.0 kV, 40 μs: (1) The trench is occupied by the ion sheath quickly due to the sheath overlapping from both side walls; this effect is not seen in the L-shape workpiece with only one side wall. (2) Electrons are detected inside the trench even after the ion sheath fills the trench, which is attributed to secondary electrons emitted from the surface of the workpiece by ion impact and trapped electrostatically between the side walls. (3) The ion flux incident upon the inner surface of the trench is strongly enhanced because trapped secondary electrons ionize the filling gas as in the hollow-cathode discharge. The enhanced ionization is therefore not seen in L-shape and planar workpieces. [Copyright &y& Elsevier]

Rotating Cu/Zn plasmas produced by a coaxial plasma gun have been applied to plasma centrifuge. A separation factor of up to 10 is measured over a radius of 4 cm when a current of 13 kA and an axial magnetic field of 2.5 kG are applied. Plasma parameters are: rotation frequency ω=1.1×106 rad/s, density n∼1015 cm-3, and ion temperature Ti=10 eV. The separation factor of 2 is attained even in the plasma core where the density is higher than one-half of the peak value. This is attributed to the fact that a strong centrifugal force forms a hollow density profile which gives the density peak at a radius of 2 cm. [ABSTRACT FROM AUTHOR]