Search results for "menetelmä"

Motoriikan havainnointilomakkeen (MOQ-T) luotettavuus 6-vuotiaiden lasten arvioinnissa

2014

Tässä tutkimuksessa selvitettiin Motoriikan havainnointilomakkeen (MOQ-T) luotettavuutta arvioitsijareliabiliteetin avulla. Lisäksi tutkimuksessa tarkasteltiin MOQ-T-lomakkeen validiteettia käyttämällä kriteerimittauksena Movement Assessment Battery for Children 2 (MABC 2) -mittaria riskiryhmään tunnistettujen esikouluikäisten lasten motorisen kehityksen tason arvioimiseen. Tutkimus toteutettiin osana Suomen CP-liitto ry:n ja Niilo Mäki Instituutin Mukaan - liikun, opin ja osallistun -hanketta. Tutkimukseen osallistui Jyväskylän alueen viidestä eri esikouluryhmästä yhteensä 66 6-vuotiasta lasta, joista kaksi ryhmän aikuista täytti lapsista erilliset MOQ-T-lomakearviot internetissä. Tämän ai…

Myönteinen vertaispalaute -menetelmän vaikutukset ja toimivuus yhdessä päiväkodin esiopetusryhmässä

2005

Designing Classroom Practices for Teaching Online Inquiry : Experiences from the Field

2021

Students face several challenges when asked to locate relevant and credible information from the internet. This article introduces three principles for designing online inquiry lessons and documents what we learned from five language arts teachers from Finland who implemented and provided feedback on a learning unit framed in those design principles. Teachers implemented a researcher-designed online inquiry unit in nine upper secondary school classrooms. The unit included four 75-minute lessons sequenced to support the location, evaluation, and synthesis of information students encountered in an online inquiry task. Teachers’ diaries revealed their impressions of the unit, problems encounte…

Model nuclear energy density functionals derived from ab initio calculations

2020

We present the first application of a new approach, proposed in [Journal of Physics G: Nuclear and Particle Physics, 43, 04LT01 (2016)] to derive coupling constants of the Skyrme energy density functional (EDF) from ab initio Hamiltonian. By perturbing the ab initio Hamiltonian with several functional generators defining the Skyrme EDF, we create a set of metadata that is then used to constrain the coupling constants of the functional. We use statistical analysis to obtain such an ab initio-equivalent Skyrme EDF. We find that the resulting functional describes properties of atomic nuclei and infinite nuclear matter quite poorly. This may point out to the necessity of building up the ab init…

0.1-10 MeV Neutron Soft Error Rate in Accelerator and Atmospheric Environments

2021

Neutrons with energies between 0.1-10 MeV can significantly impact the Soft Error Rate (SER) in SRAMs manufactured in scaled technologies, with respect to high-energy neutrons. Their contribution is evaluated in accelerator, ground level and avionic (12 km of altitude) environments. Experimental cross sections were measured with monoenergetic neutrons from 144 keV to 17 MeV, and results benchmarked with Monte Carlo simulations. It was found that even 144 keV neutrons can induce upsets due to elastic scattering. Moreover, neutrons in the 0.1-10 MeV energy range can induce more than 60% of the overall upset rate in accelerator applications, while their contribution can exceed 18% in avionics.…

Proton Direct Ionization Upsets at Tens of MeV

2023

Experimental monoenergetic proton single-event upset (SEU) cross sections of a 65-nm low core-voltage static random access memory (SRAM) were found to be exceptionally high not only at low energies ($ 3 MeV and extending up to tens of MeV. The SEU cross Section from 20-MeV protons exceeds the 200-MeV proton SEU cross Section by almost a factor of 3. Similarly, monoenergetic neutron cross sections at 14 MeV are about a factor of 3 lower than the 20-MeV proton cross section. Because of Monte Carlo (MC) simulations, it was determined that this strong enhancement is due to the proton direct ionization process as opposed to the elastic and inelastic scattering processes that dominate the SEU res…

Proton Direct Ionization in Sub-Micron Technologies: Numerical Method for RPP Parameter Extraction

2022

This work introduces a numerical method to iteratively extract parameters of a rectangular parallelepiped (RPP) sensitive volume (SV) from experimental proton direct ionization SEU data. The method combines two separate numerical models. The first model estimates the average LET values for energetic ions, including protons and also heavy ions, in elemental solid targets. The second model describes the statistical variance in the energy deposition events of projectile-induced primary ionization within a RPP shaped target volume. To benchmark the method, simulated cross-section values based on RPP parameters derived with this method are compared with literature data from four SRAM devices. Th…

Benchmark of a multi-physics Monte Carlo simulation of an ionguide for neutron-induced fission products

2022

AbstractTo enhance the production of medium-heavy, neutron-rich nuclei, and to facilitate measurements of independent yields of neutron-induced fission, a proton-to-neutron converter and a dedicated ion guide for neutron-induced fission have been developed for the IGISOL facility at the University of Jyväskylä. The ion guide holds the fissionable targets, and the fission products emerging from the targets are collected in helium gas and transported to the downstream experimental stations. A computer model, based on a combination of MCNPX for modeling the neutron production, the fission code GEF, and GEANT4 for the transport of the fission products, was developed. The model will be used to i…

Simulations of the stopping efficiencies of fission ion guides

2017

With the Ion Guide Isotope Separator On-Line (IGISOL) facility, located at the University of Jyväskylä, products of nuclear reactions are separated by mass. The high resolving power of the JYFLTRAP Penning trap, with full separation of individual nuclides, capacitates the study of nuclides far from the line of stability. For the production of neutron-rich medium-heavy nuclides, fissioning of actinides is a feasible reaction. This can be achieved with protons from an in-house accelerator or, alternatively, with neutrons through the addition of a newly developed Be(p,xn)-converter. The hereby-obtained fission products are used in nuclear data measurements, for example fission yields, nuclear …

BEM-Based Magnetic Field Reconstruction by Ensemble Kálmán Filtering

2022

Abstract Magnetic fields generated by normal or superconducting electromagnets are used to guide and focus particle beams in storage rings, synchrotron light sources, mass spectrometers, and beamlines for radiotherapy. The accurate determination of the magnetic field by measurement is critical for the prediction of the particle beam trajectory and hence the design of the accelerator complex. In this context, state-of-the-art numerical field computation makes use of boundary-element methods (BEM) to express the magnetic field. This enables the accurate computation of higher-order partial derivatives and local expansions of magnetic potentials used in efficient numerical codes for particle tr…