Semi-Lagrangian (S-L for short) methods, also called quasi-Lagrangian, have been around since the early 1960’s. T.N. Krishnamurti is probably the first to use S-L method. The S-L scheme becomes really popular following Andre Robert’s work in the early 80’s (Robert 1982) when he combined the use of S-L with semi-implicit method (SLSI) which allows for large time step size because both schemes ar...

The Immersed Boundary method is one of the most useful computational methods in studying fluid structure interaction. On the other hand, the Immersed Boundary method is also known to require small time steps to maintain stability when solved with an explicit method. Many implicit or approximately implicit methods have been proposed in the literature to remove this severe time step stability con...

This paper evaluates how semi-randomly formed project groups, compared to forming groups at free will, affect students’ learning in a project-oriented setting. The findings are based on empirical data. We have analyzed students’ experiences by taking a course in the subject of Information Systems. The identified experiences are considered to be either a strength or a problem. We can conclude th...

When explicit time discretization schemes are applied to stiff reaction–diffusion equations, the stability constraint on the time step depends on two terms: the diffusion and the reaction. The part of the stability constraint due to diffusion can be totally removed if the linear diffusions are treated exactly using integration factor (IF) or exponential time differencing (ETD) methods. For syst...

The Energy Conserving semi-implicit method (ECsim), presented by Lapenta in 2017, is a Particle Cell (PIC) algorithm for the simulation of plasmas. conservation achieved within formulation that does not require any non-linear solver. A mass matrix introduced to express linearly particle-field coupling. With preserves energy machine precision. construction central nature and also main cost compu...

In recent years, Fourier spectral methods have emerged as competitive numerical methods for large-scale phase field simulations of microstructures in computational materials sciences. To further improve their effectiveness, we recently developed a new adaptive Fourier-spectral semi-implicit method (AFSIM) for solving the phase field equation by combining an adaptive moving mesh method and the s...

Collaborative filtering plays the key role in recent recommender systems. It uses a user-item preference matrix rated either explicitly (i.e., explicit rating) or implicitly (i.e., implicit feedback). Despite the explicit rating captures the preferences better, it often results in a severely sparse matrix. The paper presents a novel iterative semi-explicit rating method that extrapolates unrate...

in this paper an efficient dual time implicit approach is used to solve viscous laminar flow around two bodies with general motion. therefore, the grid includes a background grid and two sets of grids around the moving bodies. rotational and translational motions of two bodies are managed separately in this grid arrangement. in this work the overset concept for hybrid grid is used and flow vari...

Franklin William Stahl studied DNA replication, bacteriophages, and genetic recombination in the US during the mid-twentieth and early twenty-first centuries. With his colleague Matthew Meselson, Stahl performed an experiment called the Meselson-Stahl experiment, which provided evidence for a process called semi-conservative DNA replication. Semi-conservative replication is a process in which e...