Search results for "MAIS"
showing 10 items of 966 documents
Šķidra metāla plūsmas un kristalizācijas izpēte ar neitronu radiogrāfiju
2019
Darbā pētīta orientētā kristalizācija, izmantojot neinvazīvu attēlveidošanas tehniku - neitronu radiogrāfiju. Rezultāti pirmo reizi atklāj daļiņu iesalšanas procesu metāla sacietēšanas laikā makro izmērā, ir parādīts, ka daļiņu iesalšana tilpumā notiek, kad cietā un šķidrā fāze veido pusšķidru maisījumu. Eksperimenti veikti ar alvu (Sn) taisnstūrveida traukā, kas tiek elektromagnētiski maisīta un orientēti kristalizēta. Informācija par recirkulējošo plūsmu ievākta, izsekojot 355 - 500 µm gadolīnija (Gd) daļiņas, kas vizualizē plūsmas lauku jebkurā laika momentā. Rezultāti liecina, ka metalurģiskās problēmas, piem., cieta materiāla iemaisīšanu kausējumā vai dielektrisku daļiņu vienmērīgā dis…
Zemes pārvaldības likuma 8. un 8.1 panta normas un to kopsakars ar citiem tiesību avotiem.
2021
Pēc neatkarības atjaunošanas uzsāktajai zemes reformai ir nozīmīga loma, veidojot no nekustamā īpašuma izrietošās tiesiskās attiecības. Zemes reformai noslēdzoties, tika pieņemts Zemes pārvaldības likums, kuram bija jāpārņem zemes reformas tiesiskais regulējums. Tā kā ne visi zemes reformas laika lēmumi un veiktie pasākumi sasniedza vēlamos rezultātus, pieņemtajam likumam bija jānovērš pieļautās kļūdas. Labojot kļūdas, Zemes pārvaldības likumā ir ietverts 8. un 8.1 pants. Šiem pantiem ir jānoregulē ar ceļiem un ielām saistītās, bet vēl nenoregulētās tiesiskās attiecības. Turklāt ir jānovērš arī uz šo problēmu attiecināmie tiesvedību riski. Tomēr, kā liecina veiktais pētījums, minētais mērķi…
Self and others in school bullying and cyberbullying : Fine-tuning a new arts-based method to study sensitive topics
2023
Despite continuous international research and prevention efforts, bullying not only persists globally but also evolves into new forms, such as cyberbullying. In this methodological article, we present a new arts-based research tool, graphic vignettes, that can extend our understanding of peer aggression and other sensitive topics by facilitating participants’ creative reflection over the roles of self and others in different problem-based situations. Each graphic vignette, designed for this study, looks like an incomplete comic strip that participants individually develop further. Flexible and open to interpretation vignettes were used in combination with more restrictive/structured vignett…
Long-baseline neutrino oscillation physics potential of the DUNE experiment
2020
The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is determined, based on a full simulation, reconstruction, and event selection of the far detector and a full simulation and parameterized analysis of the near detector. Detailed uncertainties due to the flux prediction, neutrino interaction model, and detector effects are included. DUNE will resolve the neutrino mass ordering to a precision of 5σσ, for all δCPδCP values, after 2 years of running with the nominal detector design and beam configuration. It has the potential to observe charge-parity violation in the neutrino sector to a precision of 3σσ (5σσ) after an exposure of 5 (10) years, for 50% o…
Low exposure long-baseline neutrino oscillation sensitivity of the DUNE experiment
2022
The Deep Underground Neutrino Experiment (DUNE) will produce world-leading neutrino oscillation measurements over the lifetime of the experiment. In this work, we explore DUNE’s sensitivity to observe charge-parity violation (CPV) in the neutrino sector, and to resolve the mass ordering, for exposures of up to 100 kiloton-megawatt-calendar years (kt-MW-CY), where calendar years include an assumption of 57% accelerator uptime based on past accelerator performance at Fermilab. The analysis includes detailed uncertainties on the flux prediction, the neutrino interaction model, and detector effects. We demonstrate that DUNE will be able to unambiguously resolve the neutrino mass ordering at a 4…
Optimization of the JUNO liquid scintillator composition using a Daya Bay antineutrino detector
2021
To maximize the light yield of the liquid scintillator (LS) for the Jiangmen Underground Neutrino Observatory (JUNO), a 20 t LS sample was produced in a pilot plant at Daya Bay. The optical properties of the new LS in various compositions were studied by replacing the gadolinium-loaded LS in one antineutrino detector. The concentrations of the fluor, PPO, and the wavelength shifter, bis-MSB, were increased in 12 steps from 0.5 g/L and 0.01 mg/L to 4 g/L and 13 mg/L, respectively. The numbers of total detected photoelectrons suggest that, with the optically purified solvent, the bis-MSB concentration does not need to be more than 4 mg/L. To bridge the one order of magnitude in the detector s…
Deep Underground Neutrino Experiment (DUNE) Near Detector Conceptual Design Report
2021
The Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are at the forefront of astrophysics and particle physics research. DUNE will study questions pertaining to the preponderance of matter over antimatter in the early universe, the dynamics of supernovae, the subtleties of neutrino interaction physics, and a number of beyond the Standard Model topics accessible in a powerful neutrino beam. A critical component of the DUNE physics program involves the study of changes in a powerful beam of neutrinos, i.e., neutrino oscillations, as the neutrinos propagate a long distance. The experiment co…
Studies of transition-edge sensor physics : thermal models and noise
2011
This thesis focuses on studying the noise in transition-edge sensors (TES). More specifically, the aim is to find an explanation for the observed excess noise that is limiting their performance and has been troubling the TES field in recent years. Several theories have been put forth but a definitive answer is still missing. In the early stages of this thesis work a novel theory was presented for the noise in a special TES geometry. In our theory the excess noise is caused by correlated fluctuations of superconductivity at the phase boundary between normal and superconducting states. Data from more recent experiments does not give solid support for the theory and in this thesis the validity…