Search results for " Stab"
showing 10 items of 1773 documents
Nonlinear relaxation phenomena in metastable condensed matter systems
2016
Nonlinear relaxation phenomena in three different systems of condensed matter are investigated. (i) First, the phase dynamics in Josephson junctions is analyzed. Specifically, a superconductor-graphene-superconductor (SGS) system exhibits quantum metastable states, and the average escape time from these metastable states in the presence of Gaussian and correlated fluctuations is calculated, accounting for variations in the the noise source intensity and the bias frequency. Moreover, the transient dynamics of a long-overlap Josephson junction (JJ) subject to thermal fluctuations and non-Gaussian noise sources is investigated. Noise induced phenomena are observed, such as the noise enhanced s…
Stabilization Effects of Dichotomous Noise on the Lifetime of theSuperconducting State in a Long Josephson Junction
2015
We investigate the superconducting lifetime of a long overdamped current-biased Josephson junction, in the presence of telegraph noise sources. The analysis is performed by randomly choosing the initial condition for the noise source. However, in order to investigate how the initial value of the dichotomous noise affects the phase dynamics, we extend our analysis using two different fixed initial values for the source of random fluctuations. In our study, the phase dynamics of the Josephson junction is analyzed as a function of the noise signal intensity, for different values of the parameters of the system and external driving currents. We find that the mean lifetime of the superconductive…
Phase dynamics in graphene-based Josephson junctions in the presence of thermal and correlated fluctuations
2014
In this work we study by numerical methods the phase dynamics in ballistic graphene-based short Josephson junctions. The supercurrent through a graphene junction shows a non-sinusoidal phase-dependence, unlike a conventional junction ruled by the well-known d.c. Josephson relation. A superconductor-graphene-superconductor system exhibits superconductive quantum metastable states similar to those present in normal current-biased JJs. We explore the effects of thermal and correlated fluctuations on the escape time from these metastable states, when the system is stimulated by an oscillating bias current. As a first step, the analysis is carried out in the presence of an external Gaussian whit…
Lifetime of the superconductive state in long Josephson junctions in presence of non-Gaussian noise sources
2012
The effects of Lévy noise sources on the transient dynamics of long Josephson junctions (LJJ) are investigated in the presence of both a periodical current signal and a noise source with Gaussian, Cauchy-Lorentz or Levy-Smirnov probability distributions. In particular, by numerically integrating the Sine-Gordon equation, the mean escape time (MET) from the superconductive metastable state is obtained as a function both of the frequency of the periodical force and amplitude of the noise signal. We find resonant activation (RA) and noise enhanced stability (NES). Significative changes in RA and NES are observed by using Lévy noise sources with different statistics. MET is also studied as a fu…
Jueces y «control de calidad» de los sistemas políticos
2007
Maria.J.Anon@uv.es Este artículo trata de analizar la tesis normativa que atribuye a los jueces la función de garantía de la estabilidad de los sistemas políticos, examen que se lleva a cabo en dos planos. En primer lugar, realizo una valoración de la contribución de la regla de reconocimiento a la identidad y a la legitimidad de los sistemas jurídicos. Planteo, después, la idea de que el rasgo distintivo de la función judicial desde un punto de vista institucional y normativo no es tanto el mantenimiento de la estabilidad del orden político cuanto la garantía de los derechos, subrayando las limitaciones de la tesis analizada en este artículo en contextos de transformación del orden jurídic…
Jā-Nē balsošanas sistēmas
2015
Bakalaura darbs iepazīstina ar Jā-Nē balsošanas sistēmām. Darbā aprakstītas nosvarotas, stabilas pret maiņām, stabilas pret tirdzniecību, vektoru nosvarotas Jā-Nē balsošanas sistēmas un sakarības starp tām. Ilustrācijai apskatīttas četras balsošanas sistēmas. Noslēgumu daļā aplūkota balsošanas sistēmas dimensionalitāte. Darbs ir metodiska rakstura.
Zvaigžņotā Debess: 60.gadskārta
2019
Contents: In Remembrance of Jānis Ikaunieks, Arturs Balklavs and Andrejs Alksnis: I.Pundure. «ZVAIGŽŅOTĀ DEBESS» Was Leading to the Truth … ; I.Pundure. Astronomers of Latvian Origin in IAU Management ; DISCOVERIES: I.Pundure. Gaia’s Most Accurate Star Map of Milky Way and Its Surroundings ; SPACE RESEARCH and EXPLORATION: I.Pundure. ESA Selects Three New Missions to Explore the Universe ; LATVIAN SCIENTISTS: The List of Popular Science Papers (1958-2016) by Professor Andrejs Alksnis (concluded) ; In memoriam: Dr.sc.ing. Edgars Bervalds (1936-2019) ; In memoriam: Dr.phys. Natālija Cimahoviča (1926-2019) ; FLASHBACK: I.Pundure. On Hawking’s Publication in the Vatican’s Commentarii Series ; F…
Humīnskābju izdalīšana no kūdras un to pētīšana
2017
Bakalaura darba ietvaros tika izpētīta attiecīgā zinātniskā, metodiskā un mācību literatūra par humusvielām, to izdalīšanas metodēm un humīnskābju pētīšanas metodēm. No astoņiem kūdras paraugiem divos eksperimentos tika izdalītas humīnskābes un noteiktas to masas daļas. Izmantojot FTIR-ATR metodi tika uzņemti un analizēti humīnskābju IS spektri un lietojot Kjeldāla metodi noteica slāpekļa daudzums paraugos. Izdalītajām kūdras humīnskābem, lietojot izotopu attiecību masspektrometriju, noteica 13C un 15N.
Stability of solution for Rao-Nakra sandwich beam model with Kelvin-Voigt damping and time delay
2022
This paper deals with stability of solution for a one-dimensional model of Rao?Nakra sandwich beam with Kelvin?Voigt damping and time delay given by ??1?1?????? ? ??1?1?????? ? ??(??? + ?? + ??????) ? ?????????? ? ??????????( ? , ?? ? ??) = 0, ??3?3?????? ? ??3?3?????? + ??(??? + ?? + ??????) ? ?????????? = 0, ????????? + ?????????????? ? ????(??? + ?? + ??????)?? ? ?????????? = 0. A sandwich beam is an engineering model that consists of three layers: two stiff outer layers, bottom and top faces, and a more compliant inner layer called ?core layer?. Rao?Nakra system consists of three layers and the assumption is that there is no slip at the interface between contacts. The top and bottom lay…
Structure–activity relationships, and drug metabolism and pharmacokinetic properties for indazole piperazine and indazole piperidine inhibitors of RO…
2007
ROCK has been implicated in many diseases ranging from glaucoma to spinal cord injury and is therefore an important target for therapeutic intervention. In this study, we have designed a series of 1-(4-(1H-indazol-5-yl)piperazin-1-yl)-2-hydroxy(or 2-amino) analogs and a series of 1-(4-(1H-indazol-5-yl amino)piperidin-1-yl)-2-hydroxy(or 2-amino) inhibitors of ROCK-II. SR-1459 has IC50 = 13 nM versus ROCK-II while the IC50s for SR-715 and SR-899 are 80 nM and 100 nM, respectively. Many of these inhibitors, especially the 2-amino substituted analogs for both series, are modest/potent CYP3A4 inhibitors as well. However, a few of these inhibitors (SR-715 and SR-899) show strong selectivity for R…