Splashplate feeds, e.g. [1], are increasingly used for high performance parabolic antennas. The feed is directly interfaced in the focus of the antenna by a straight circular waveguide through the antenna vertex which simultaneously acts as feed support. At the far side of the waveguide, the need of a circularto-rectangular waveguide transition is obvious to overcome proper interfacing with sta...

Steel beam cross sections are normally classified according to the effect of local buckling on the moment capacity of the section. This is achieved by defining slenderness limits for the flange and the web. This paper describes a series of bending tests on cold-formed RHS to examine these limits. The resulting experimental relationship between web slenderness and plastic rotation capacity is gi...

nonlinear hunting speeds of railway vehicles running on a tangent track are analytically obtained using hopf bifurcation theory in this paper. the railway vehicle model consists of nonlinear primary yaw dampers, nonlinear flange contact stiffness as well as the clearance between the wheel flange and rail tread. linear and nonlinear critical speeds are obtained using bogoliubov method. a compreh...

In order to solve the problem that due to the unreasonable parameter Settings when use CAE analysis to produce the cars covering parts mould, such as sheet wrinkling, cracking, and more than an acceptable range of rebound. This article used CAE analysis software to find relatively reasonable parameters to achieve a reasonable analysis in the process of sheet metal forming defects and to put for...

The early Middle Jurassic is regarded as the period when sauropods diversified and became major components of the terrestrial ecosystems. Not many sites yield sauropod material of this time; however, both cranial and postcranial material of eusauropods have been found in the Cañadón Asfalto Formation (latest Early Jurassic-early Middle Jurassic) in Central Patagonia (Argentina), which may help ...

We present the results of an experimental investigation on the wrinkling of positively curved surfaces and explore their use towards drag reduction applications. In our precision model experiments we make use of rapid prototyping techniques to cast samples with custom geometry and material properties out of silicone-based rubbers. Our structures consist of a thin stiff shell that is chemically ...

Complex wrinkle patterns have been observed in various thin film systems, typically with integrated hard and soft materials for various applications as well as in nature. The underlying mechanism of wrinkling has been generally understood as a stress-driven instability. On an elastic substrate, equilibrium and energetics set the critical condition and select the wrinkle wavelength and amplitude...

Textured surfaces, formed through wrinkling and folding, are observed abundantly in nature. We are especially motivated by the unique capabilities of some species of cuttlefish that camouflage themselves by rapidly switching from smooth to textured skin by expressing protuberances called papillae. Inspired by this, we developed a shape memory alloy– elastomer composite as a platform for reversi...