Search results for "SIM"

A Spline Collocation Scheme for the Spherical Shallow Water Equations

1999

OPKINE, a multipurpose program for kinetics

1991

The program OPKINE is presented for the study of reaction mechanisms and multicomponent analysis in dynamic conditions. This program is written in FORTRAN-77 for IBM 30/90 and VAX 8300 computers, and permits the simultaneous evaluation of both rate constants and initial reagent concentrations or, alternatively, rate constants and sensitivities. Up to 20 kinetic curves, with up to 400 points each, can be treated to evaluate up to 40 parameters. Integration of the system of differential equations is performed by means of the Runge–Kutta–Fehlberg method. OPKINE is provided with the Simplex, and modified versions of the Davidon–Fletcher–Powell and Gauss–Newton–Marquardt optimization methods. A …

Effective strategies for targeted attacks to the network of Cosa Nostra affiliates

2022

AbstractNetwork dismantling has recently gained interest in the fields of intelligence agencies, anti-corruption analysts and criminal investigators due to its efficiency in disrupting the activity of malicious agents. Here, we apply this approach to detect effective strategies for targeted attacks to Cosa Nostra by analysing the collaboration network of affiliates that participate to the same crimes. We preliminarily detect statistically significant homophily patterns induced by being member of the same mafia syndicate. We also find that links between members belonging to different mafia syndicates play a crucial role in connecting the network into a unique component, confirming the releva…

On optimal estimates for the solutions of linear difference equations on the circle

1976

A linear difference equation arising in the proof of Moser's twist mapping theorem is solved and optimal estimates for the solution are established.

Navigationsformel zu A. Busemanns Variationsproblem der Raumfahrt

1970

Die Indikatrix des Variationsproblems wird auser durch die Storungsdifferentialgleichung fur die grose Halbachse und die Exzentrizitat durch einen Zusammenhang zwischen der Richtung des Impulsausstoses und der exzentrischen Anomalie gegeben. Die Hamilton-Gleichungen einer Extremalen reduzieren sich dann auf eine Navigationsgleichung. Die restlichen Storungsgleichungen fur die Perihellange und die mittlere Lange der Epoche geben schlieslich den sparsamsten zeitlichen Ablauf des Raketenausstoses.

Shooting methods for 1D steady-state free boundary problems

1993

AbstractIn this note, we present two numerical methods based on shooting methods to solve steady-state diffusion-absorption models.

On the preparation of simple and universal buffers including polynuclear species

1986

A simple generalized procedure for the calculation of electrolyte concentrations in pH-buffers is proposed. Mixtures of acid-base systems and formation of polynuclear species at high ionic strengths are considered, and a diagram useful for the study and preparation of the buffers is shown.

Structure‐Activity Relationships of Benzamides and Isoindolines Designed as SARS‐CoV Protease Inhibitors Effective against SARS‐CoV‐2

2020

Abstract Inhibition of coronavirus (CoV)‐encoded papain‐like cysteine proteases (PLpro) represents an attractive strategy to treat infections by these important human pathogens. Herein we report on structure‐activity relationships (SAR) of the noncovalent active‐site directed inhibitor (R)‐5‐amino‐2‐methyl‐N‐(1‐(naphthalen‐1‐yl)ethyl) benzamide (2 b), which is known to bind into the S3 and S4 pockets of the SARS‐CoV PLpro. Moreover, we report the discovery of isoindolines as a new class of potent PLpro inhibitors. The studies also provide a deeper understanding of the binding modes of this inhibitor class. Importantly, the inhibitors were also confirmed to inhibit SARS‐CoV‐2 replication in …

Comparison of implementations of the lattice-Boltzmann method

2008

AbstractSimplicity of coding is usually an appealing feature of the lattice-Boltzmann method (LBM). Conventional implementations of LBM are often based on the two-lattice or the two-step algorithm, which however suffer from high memory consumption and poor computational performance, respectively. The aim of this work was to identify implementations of LBM that would achieve high computational performance with low memory consumption. Effects of memory addressing schemes were investigated in particular. Data layouts for velocity distribution values were also considered, and they were found to be related to computational performance. A novel bundle data layout was therefore introduced. Address…

Stochastic analysis of dynamical systems with delayed control forces

2006

Abstract Reduction of structural vibration in actively controlled dynamical system is usually performed by means of convenient control forces dependent of the dynamic response. In this paper the existent studies will be extended to dynamical systems subjected to non-normal delta-correlated random process with delayed control forces. Taylor series expansion of the control forces has been introduced and the statistics of the dynamical response have been obtained by means of the extended Ito differential rule. Numerical application provided shows the capabilities of the proposed method to analyze stochastic dynamic systems with delayed actions under delta-correlated process contrasting statist…