We construct a class of projected entangled pair states which is exactly the resonating valence bond wave functions endowed with both short range and long range valence bonds. With an energetically preferred resonating valence bond pattern, the wave function is simplified to live in a one-parameter variational space. We tune this variational parameter to minimize the energy for the frustrated s...

This paper describes a systematic method of refining a computational grid for the Direct Numerical Simulation (DNS) of flow about a square cylinder. The grid refinement method involves two stages. The first stage constructs computational meshes based on reasonable estimates of cell size and grid stretching ratios and investigates the sensitivity of the computed flow field to these parameters. T...

For flow-induced vibration of a rounded-square cylinder under the effect proximity interference by stationary splitter plate downstream, numerical study is presented for various corner-radius R(0.1−0.5), reduced velocity U*(2−12.5), cylinder-plate gap G*(0.3,2.0), Reynolds number Re = 100, mass ratio M*=1, damping coefficient ζ=0.005, plate-length L*=1, and plate-thickness t*=0.05. R, vortex-in...

Inexpensive digital valves are implemented to accurately control the position of a pneumatic cylinder using pulse width modulation (PWM) technique. A fuzzy PI controller is designed and implemented to overcome the nonlinearity inherited in the system due to air compressibility, dry friction and the nature of the digital valves. The actuator under control is a vertical double-acting single-rod p...

This study is focused on twoand three-dimensional incompressible flow past a circular cylinder for Reynolds number Re 6 1000. To gain insight into the mechanisms underlying the suppression of unsteadiness for this flow we determine the nonlinear optimal open-loop control driven by surface-normal wall transpiration. The spanwise-constant wall transpiration is allowed to oscillate in time, althou...

We introduce single-step proximal policy optimization, a deep reinforcement learning algorithm for situations where neural network optimization does not depend on state. Optimization is examined with open-loop control problems of laminar and turbulent flows (Re up to few ${10}^{4}$). For flow past square cylinder, the approach reduces drag by 30% finding best placement small in agreement existi...

PURPOSE To compare the final changes in corneal wavefront aberration by limbal relaxing incisions (LRIs) after cataract surgery. METHODS This prospective cumulative interventional nonrandomized case study included cataract and astigmatic patients undergoing LRIs and phaco with intraocular lens implantation. LRIs were planned using Donnenfeld nomogram. The root mean square of corneal wave aber...

In this research numerical simulations are performed, using the multi-relaxation-time lattice Boltzmann method, in the range 3 ≤ β = w[d] ≤ 30 at Re = 100, 200 and 300, where β the blockage ratio, w is the equispaced distance between centers of cylinders, d is the diameter of the cylinder and Re is the Reynolds number, respectively. Special attention is paid to the effect of the equispaced dist...

The classical k ? " model and a new implementation of wall-laws have been evaluated for unsteady turbulent ows past square and circular cylinders. We show that good numerics can lead to a serious improvement of the results. In the case of the ow past a square cylinder (Lyn's test case), results agree surprisingly well with the experimental data. In the analysis of the vortex shedding ow past a ...

Solutions of stress intensity factors for external and internal unpressurized and pressurized surface cracks in internally pressurized thick-walled reactor pressure vessels are determined directly by a three-dimensional displacement-hybrid finite element method. The finite element method is based on a rigorous modified variational principle of the total potential energy, with arbitrary element ...