Peak structural response to nonstationary random excitations

Study establishes distribution function of peak response values, based on frequency interpretation. Excitations considered include impact loading on landing gears and aircraft gust loading. Because of relative severity of excitations, prediction of fatigue and maximum response characteristics is important part of task of structural analysis and design

A note on the first passage time problem

Kolmogoroff backward equation for analyzing first passage time problem for linear single degree of freedom vibratory system with linear viscous dampin

On the bound of first excursion probability

Boundary values for first excursion probability as related to reliability and safe performance of mechanical and structural system

Optimum structural design based on reliability and proof-load testing

Proof-load test eliminates structures with strength less than the proof load and improves the reliability value in analysis. It truncates the distribution function of strength at the proof load, thereby alleviating verification of a fitted distribution function at the lower tail portion where data are usually nonexistent

Assessment of Molecular Cytogenetic Methods for the Detection of Chromosomal Abnormalities

Some marker chromosomes and chromosome rearrangements are difficult to identify using G-bands by Giemsa staining after trypsin treatment (G-banding) alone. Molecular cytogenetic techniques, such as spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH), can help to detect chromosomal aberrations precisely. We analyzed the karyotypes in 6 cases of multiple congenital abnormalities and 1 case of spontaneous abortion (case 2). Three cases (cases 1, 6, and 7) had marker chromosomes, and 4 cases (cases 2-5) had chromosomal rearrangements. The karyotypes in cases 1, 2, and 3 were determined using FISH with probes based on the clinical findings and family histories. Spectral karyotyping (SKY) analysis in cases 4-7 showed that this method is useful and saves time. The combination of SKY and FISH analyses defi ned the range of the ring chromosome in case 7. We demonstrated that a combination of G-banding, FISH, and SKY can be applied effectively to the investigation of chromosomal rearrangement and to the detection of marker chromosome origins. We suggest the use of these methods for prenatal diagnosis, in which the inherent time limitations are particularly important

Simplified Formula for Axial Strains of Buried Pipes Induced by Propagating Seismic Waves

Pipe strains developed in buried straight pipes by horizontally propagating seismic waves are analyzed. Extensive discussion is made for the general slippage conditions between soils and pipes, as well as for the arbitrary angle of incidence of the longitudinal and transverse waves relative to the pipe axis. After the pipe strain solutions and their upper and lower bounds are obtained for the given values of the angle of incidence, solutions for the maximum pipe strains with unknown angles of incidence are discussed. In particular, simple approximate closed-form solutions for the maximum pipe strains developed herein should be useful for practical applications

Heating of Accelerator Targets Behaviours

開始ページ、終了ページ: 冊子体のページ付

Effect of self-weight and vertical acceleration on the behaviour of tall structures during earthquake

The effect of self-weight and vertical ground acceleration during earthquakes on vertical cantilevers has been studied. The input is taken to be a bivariate normal random process, digitally simulated on a computer. The tip deflection, base moment and shear force have been obtained numerically for three structures of different natural frequencies. It is found that the presence of self-weight and vertical ground excitation could alter these three quantities considerably. This leads to the conclusion that with tall structures a refined analysis, similar to the one presented here, is advisable