Search results for "simulointi"
showing 10 items of 148 documents
Hidden attractors in dynamical models of phase-locked loop circuits : limitations of simulation in MATLAB and SPICE
2017
During recent years it has been shown that hidden oscillations, whose basin of attraction does not overlap with small neighborhoods of equilibria, may significantly complicate simulation of dynamical models, lead to unreliable results and wrong conclusions, and cause serious damage in drilling systems, aircrafts control systems, electromechanical systems, and other applications. This article provides a survey of various phase-locked loop based circuits (used in satellite navigation systems, optical, and digital communication), where such difficulties take place in MATLAB and SPICE. Considered examples can be used for testing other phase-locked loop based circuits and simulation tools, and m…
Peeling of multilayer graphene creates complex interlayer sliding patterns
2015
Peeling, shearing, and sliding are important mechanical phenomena in van der Waals solids. However, theoretically they have been studied mostly using minimal periodic cells and in the context of accurate quantum simulations. Here, we investigate the peeling of large-scale multilayer graphene stacks with varying thicknesses, stackings, and peeling directions by using classical molecular dynamics simulations with a registry-dependent interlayer potential. Simulations show that, while at large scale the peeling proceeds smoothly, at small scale the registry shifts and sliding patterns of the layers are unexpectedly intricate and depend both on the initial stacking and on the peeling direction.…
Playing with Time in Digital Fiction
2015
The exceptional quality of digital fictions lies in their inherently dynamic nature, how they may be flexibly programmed to generate new content and alter the already existing contents. This adds a new temporal level, compared to traditional fictions. Digital games, especially, incorporate aspects of simulation and narration in their structure. As interactive and dynamic media form, games are specifically temporal in nature. They offer us the flexibility and preciseness of digital simulations, with the potential of psychologically engaging narrative qualities, which together open up a whole new field of experimenting with temporally dynamic media. Much of the new media fictions partake in a…
Guiding Student Thinking Through Teacher Questioning When Learning with Dynamic Representations
2021
Dynamic representations (e.g., dynamic geometry software GeoGebra for mathematics learning and PhET simulations for science learning) offer excellent opportunities for students to conduct investigations and to formulate explanations for the visualized phenomena. In order for this to be effective, students need guidance, for example, for planning their investigations and reflecting on their actions. One way to support students is by prompting them by using questions that are adapted to the students’ current situation. This chapter focuses on how pre-service teachers provide guidance for students through questioning and by both structuring and problematizing student learning. Data comes from …
Service platform implementation for simulation systems
2016
Nykyään olemassa olevia simulaatiojärjestelmiä hyödynnetään koneiden itseoppimisen ja tietojärjestelmäpohjaisten (KDD) alustojen kehityksessä. Tämän takia simulaatioiden merkitys ja vaikutus tulee kasvamaan suuressa määrin jokapäiväisessä elinympäristössämme. Yritykset kuten Ahphabet (Google), Facebook ja SpaceX edustavat yrityksinä kehitystä mallintamiseen ja simulointiin siirtyvästä tavasta kehittää MDA pohjaisia tuotteita itsenäisesti toimivista autoista avaruustutkimukseen. Ihmisen näkökulmasta nykyinen kehitys tulee muuttamaan ympäristöä tavalla, jossa kanssakäyminen koneiden kanssa muuttuu luonnolliseksi osaksi arkea. Tutkielman Tarkoituksena oli suunnitella ja toteuttaa palvelualusta…
Getting even with CLE
2018
In the landscape of approaches toward the simulation of Lattice Models with complex action the Complex Langevin (CL) appears as a straightforward method with a simple, well defined setup. Its applicability, however, is controlled by certain specific conditions which are not always satisfied. We here discuss the procedures to meet these conditions and the estimation of systematic errors and present some actual achievements.
Handover performance in IEEE 802.16 mobile networks
2009
Effects of particle clustering on the plastic deformation and damage initiation of particulate reinforced composite utilizing X-ray CT data and finit…
2018
In this paper, a new simulation technique which can include microstructural inhomogeneity of particulate reinforced composites is proposed to accurately study deformation pattern and damage mechanism in these composites. Three dimensional microstructures constructed from XCT images incorporated into finite element modeling codes with minimal approximation to capture the effects of cluster size, local volume fraction of particles in the cluster and the distance between clusters as relevant statistical quantities describing the microstructural inhomogeneity of particulate reinforced composites. A quantitative parameter as degree of clustering is defined to consider particle clustering effect.…