assessing the behavior of composite structures which are subjected to impact loads is one of the important subjects in the field of mechanical sciences. using thin-walled tubes which collapsed and absorbed the impact energy is a well-known method to prevent damages to the other parts of the structures. in this paper, deformations, crushing length, peak load, mean force and energy absorption cap...

OBJECTIVES For needle insertion and guidewire placement during central venous catheterization, a thin-wall introducer needle technique and a cannula-over-needle technique have been used. This study compared these two techniques regarding the success rates and complications during internal jugular vein catheterization. DESIGN Prospective, randomized, controlled study. SETTING A university-af...

The stability and evolution of ferroelectric domain structures in thin films are studied. Elastic solutions are derived for both elastically anisotropic and isotropic thin films with arbitrary domain structures, subject to the mixed stressfree and constraint boundary conditions. These solutions are employed in a three-dimensional phase-field model to investigate simultaneously the effect of sub...

Replaceable energy dissipation elements can reduce damage to main structures and improve seismic resistance of bridge structures. However, in existing studies, replaceable are mainly arranged the transverse direction structure, while little attention is given longitudinal bridge, which also suffers from serious under earthquakes. This paper proposes an innovative double-limb-thin-wall (DLTW) pi...

The fine structure of Bacillus subtilis has been studied by observing sections fixed in KMnO(4), OsO(4), or a combination of both. The majority of examinations were made in samples fixed in 2.0 per cent KMnO(4) in tap water. Samples were embedded in butyl methacrylate for sectioning. In general, KMnO(4) fixation appeared to provide much better definition of the boundaries of various structures ...

Instantaneous velocity fields in the x-y plane of a zero pressure gradient turbulent boundary layer are measured using particle image velocimetry. It is found that there exist random, time-varying zones in the U-V fields in which the streamwise momentum is remarkably uniform. The largest dimension of a typical zone is proportional to the boundary layer thickness. The zone closest to the wall co...

Comparative study of microfossils from two kinds of sediments: chert intercalations (studied in thin section) and phosphorite/phosphatic carbonate (in thin section and maceration), from the upper Neoproterozoic Doushantuo phospho− rites in the Weng’an area, Guizhou Province, South China, shows that the phosphatized Megasphaera ornata and the chert−preserved Tianzhushania tuberifera should be re...

The effect of finite wall thickness on the stability of n=1 resistive wall modes in toroidal plasmas is investigated. A fusion reactor-relevant configuration is examined. The investigation employs a novel ideal-magnetohydrodynamics adaptive shooting code for axisymmetric plasmas, extended to take into account the wall thickness. Although finite wall thickness generally reduces the growth rate o...

thin-walled hollow steel columns, either circular or box shaped, are commonly used as piers in bridges. recent earthquakes, e.g. hyogoken-nanbu or kobe 1995, on the other hand have shown that these columns are vulnerable to damage when subjected to earthquake loading. this paper presents a new innovative thin-walled hollow steel column fabricated of corrugated plates, “thin-walled steel columns...