At present, most precast shear walls are implemented in accordance with the method equivalent to a cast-in-place structure, where joint is complicated, and construction difficult. According characteristics of wall structures, design “strong horizontal joints, weak vertical joints” for structure proposed. The existing was used form strong damper connect joints joints. It can reduce pouring concr...

Is the common folklore, that oars are less efficient at propulsion than propellers, correct? Here we examine the propulsive efficiency of the oars used in competitive rowing. We take the propulsive efficiency η of rowing to be the ratio of the energetic benefit, the energy Db dissipated by boat drag, to the energetic cost, the work Wr performed by the rower. Air drag is neglected as is the ener...

Optimal control of dampers has been proposed to mitigate vibration effects in mechanical systems. In many cases, systems are subject to periodic forcing and the goal is to maximize the energy dissipated by the damper. In contrast to prior work utilizing instantaneous or infinite-time−horizon optimization, this paper employs periodic optimal control to maximize the energy dissipated per cycle. F...

A model is proposed, which predicts the toughness of 7000 series aluminium alloys in a variety of situations, including two alloy compositions, different quench rates from the solution treatment temperature and ageing states from underaged to overaged. The model is derived in three steps. The energy dissipated by transgranular fracture is first calculated, using a simplified cohesive zone appro...

wear is a complicated phenomenon caused by the relative movement of two contacting surfaces compressed together by a normal force. prediction of the wear, in most cases, requires various experiments and microstructural characterization of the contacting surfaces. mathematical models based on physical concepts could provide considerable help in understanding the physical behavior and hence the p...

The dependence of intermittent inertial properties on ultraviolet eddy viscosity closures is examined within the framework of shellmodels of turbulent flows. Inertial intermittent exponents turn out to be fairly independent on the way energy is dissipated at small scales.