Shadowing Effect on the Statistical Characteristics of Specular Elements in the Multipath Propagation Over Sea

1998 ◽  
Vol 52 (5) ◽  
pp. 22-28
Author(s):  
Yu. F. Logvinov
Keyword(s):  
Multipath Propagation ◽  
Statistical Characteristics ◽  
Shadowing Effect

Ultra high resolution SEM at high voltage images individual fab fragments applied as molecular label to cell surface receptors

1989 ◽  
Vol 47 ◽  
pp. 70-71
Author(s):  
Klaus-Ruediger Peters
Keyword(s):  
High Resolution ◽  
High Energy ◽  
Metal Coating ◽  
Beam Diameter ◽  
Surface Receptors ◽  
Surface Mobility ◽  
Metal Atoms ◽  
Shadowing Effect ◽  
Imaging Mode ◽  
Deposition Techniques

Topographic ultra high resolution can now routinely be established on bulk samples in cold field emission scanning electron microscopy with a second generation of microscopes (FSEM) designed to provide 0.5 nm probe diameters. If such small probes are used for high magnification imaging, topographic contrast is so high that remarkably fine details can be imaged on 2DMSO/osmium-impregnated specimens at ribosome surfaces even without a metal coating. On TCH/osmium-impregnated specimens topographic resolution can be increased further if the SE-I imaging mode is applied. This requires that beam diameter and metal coating thickness be made smaller than the SE range of ~1 nm and background signal contributions be reduced. Subnanometer small probes can be obtained (only) at high accelerating voltages. Subnanometer thin continuous metal films can be produced under the following conditions: self-shadowing effect between metal atoms must be reduced through appropriate deposition techniques and surface mobility of metal atoms must be diminished through high energy sputtering and/or specimen cooling.

Influence of Yield Strength Variability over Cross-Section to Steel Beam Load-Carrying Capacity

2005 ◽  
Vol 10 (2) ◽  
pp. 151-160 ◽  
Author(s):  
J. Kala ◽  
Z. Kala
Keyword(s):  
Yield Strength ◽  
Cross Section ◽  
Carrying Capacity ◽  
Bending Moment ◽  
Statistical Characteristics ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Strength Variability ◽  
Hot Rolled ◽  
Hot Rolled Steel

Authors of article analysed influence of variability of yield strength over cross-section of hot rolled steel member to its load-carrying capacity. In calculation models, the yield strength is usually taken as constant. But yield strength of a steel hot-rolled beam is generally a random quantity. Not only the whole beam but also its parts have slightly different material characteristics. According to the results of more accurate measurements, the statistical characteristics of the material taken from various cross-section points (e.g. from a web and a flange) are, however, more or less different. This variation is described by one dimensional random field. The load-carrying capacity of the beam IPE300 under bending moment at its ends with the lateral buckling influence included is analysed, nondimensional slenderness according to EC3 is λ¯ = 0.6. For this relatively low slender beam the influence of the yield strength on the load-carrying capacity is large. Also the influence of all the other imperfections as accurately as possible, the load-carrying capacity was determined by geometrically and materially nonlinear solution of very accurate FEM model by the ANSYS programme.

Spatial Statistical Characteristics of Soil

2003 ◽  
Vol 59 (3-4) ◽  
pp. 10
Author(s):  
Ye. V. Tarnavsky ◽  
G. P. Kulemin
Keyword(s):  
Statistical Characteristics
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