Search results for "NAK"
showing 10 items of 469 documents
Quantum Backreaction on Three-Dimensional Black Holes and Naked Singularities
2016
We analytically investigate backreaction by a quantum scalar field on two rotating Ba\~nados-Teitelboim-Zanelli (BTZ) geometries: that of a black hole and that of a naked singularity. In the former case, we explore the quantum effects on various regions of relevance for a rotating black hole space-time. We find that the quantum effects lead to a growth of both the event horizon and the radius of the ergosphere, and to a reduction of the angular velocity, compared to the unperturbed values. Furthermore, they give rise to the formation of a curvature singularity at the Cauchy horizon and show no evidence of the appearance of a superradiant instability. In the case of a naked singularity, we f…
An Anthropological Insight on the Commonalities between Tourism and Archaeology
2019
Over the years, archaeology maturated towards something else than a scientific discipline. Archaeological sites are culturally showed as emerging and recycled tourist attractions (Robb 1998; Bateman 2006; Rowan & Baram 2004; Karlsson & Gustafsson, 2006). At a closer look, tourism is understood as a leisure activity which is enrooted in the needs of relaxing and evasion while archaeology -as a knowledge platform which is based on scientific method- explores the history of ancient cultures. This raises a more than interesting question respecting the commonalities and differences between archaeology and tourism. To some extent, archaeologists find ancient relics and objects whi…
Development of a Textile Nanocomposite as Naked Eye Indicator of the Exposition to Strong Acids
2017
[EN] Chemical burns, mainly produced by acids, are a topic of concern. A new sensing material for the detection of strong acids able to be incorporated into textiles has been developed. The material is prepared by the covalent attachment of 2,2 ',4,4 ',4 ''-pentamethoxy triphenyl methanol to a mesoporous material which further is included in a nitro resin to obtain a colourless composite. The response of this composite to diverse acid solutions was tested showing the appearance of an intense purple colour (with a colour difference higher than 160) that can be monitored by the naked eye or could be easily digitised to feed an instrumental sensor. Reversibility and resistance to washing cycle…
Poly-Gly Region Regulates the Accessibility of Metal Binding Sites in Snake Venom Peptides
2022
It is supposed that the presence of poly-His regions in close proximity to poly-Gly domains in snake venoms is related to their biological activity; poly-His/poly-Gly (pHpG) peptides inhibit the activity of metalloproteinases during venom storage via the chelation metal ions, necessary for their proper functioning. This work shows that only the histidyl residues from the N-terminal VDHDHDH motif (but not from the poly-His tag) were the primary Zn(II) binding sites and that the poly-Gly domain situated in the proximity of a central proline residue may play a regulatory role in venom gland protection. The proline induces a kink of the peptide, resulting in steric hindrance, which may modulate…
Rinnakkaislaskentamallien arviointi : Intel Threading Building Blocks
2013
Moniydinprosessoreiden ollessa jo normi on rinnakkaislaskennasta tullut arkipäivää yhä useammalle ohjelmoijalle. Rinnakkaislaskenta on hankalaa hahmottaa ja toteuttaa, joten tarvitaan uusia korkeamman abstraktiotason rinnakkaislaskentamalleja tukemaan rinnakkaislaskennan yleistymistä. Tässä tutkielmassa luomme mallin rinnakkaislaskentamallien arviointiin kahdeksasta eri näkökulmasta. Sen jälkeen tutustumme Intel Threading Building Blocks (TBB) -rinnakkaistuskirjastoon, joka lupaa tehdä rinnakkaislaskennan toteuttamisesta helpompaa siirtämällä rinnakkaistuksen perusmekanismeja pois ohjelmoijan vastuulta. Lopuksi arvioimme TBB:tä aiemmin luomamme mallin pohjalta. Toteamme, että TBB täyttää hy…
Noviisit, selaajat ja tuottajat : kuusi näkemystä Internet-koulutuksesta
1997
Metsien ennallistamisen vaikutus kaarnakuoriaisten populaatioihin ja metsätuhoriskiin
2008
Cilvēka ķermenis uzraudzīšanas telpā un vernakulārajā pasaulē: Mišela Fuko un Ivana Illiča skatījums
2021
Darbs `Cilvēka ķermenis uzraudzīšanas telpā un vernakulārajā pasaulē: Mišela Fuko un Ivana Illiča skatījums` izstrādāts balstoties autores interesē par cilvēku un viņa ķermeni, skatot to gan kā pārvaldāmu un ietekmējamu objektu, gan kā subjektu, kas spējīgs paust pašvaru, pretojoties to ietverošajām varas praksēm. Balstoties Fuko un Illiča skatījumā uz cilvēku uzraudzības telpā, atklājas šīs telpas aizvien pieaugošā sarežģītība un spriedze, kas veidojas realizējot un nemitīgi uzlabojot sabiedrības pārvaldi. Vernakulārā joma jeb pasaule ir Illiča aicinājums novērtēt dažādas cilvēka aktivitātes, kuras netiek pakļautas formālajai ekonomikai, piedāvājums aktualizēt autonomu lēmumu pieņemšanu, k…
Alma Mater: 2011/Rudens
2011
Universitātes Avīze : Alma Mater / LU Preses centrs ; LU Akadēmiskais apgāds. - Rudens (2011), 32.lpp.
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…