Search results for "NOS"
showing 10 items of 30869 documents
MySQL- ja MongoDB-tietokantojen suorituskykyvertailu
2018
Datan määrä ja rakenne on muuttunut vuosikymmenien saatossa huimasti, ja tiedonkäsittely kokee uusia haasteita jatkuvasti. Perinteiset relaatiotietokannat eivät välttämättä enää sovellu ratkaisemaan näitä ongelmia. 2000-luvun puolella vaihtoehdoksi ovat tulleet NoSQL-tietokannat, joiden tavoitteena on tarjota ratkaisukeinoja näihin uusiin haasteisiin. Tässä tutkielmassa käsitellään relaatio- ja NoSQL-tietokantojen taustoja ja eroavaisuuksia. Erityisesti tutkielmassa keskitytään tietokantojen suorituskykyyn. Tutkielmassa mitattiin ja vertailtiin MySQL ja MongoDB tietokantojen suorituskykyä, jotka edustavat vastaavasti relaatio- ja NoSQL-tietokantoja. Suorituskykytesteihin käytettiin avoimen …
SQL- ja NoSQL-tietokantojen suorituskykyerot
2016
SQL-tietokantoja on käytetty lähes tietokantojen olemassaolon alusta asti. Nykyään dataa on yhä enemmän kuin ennen, se on monipuolisempaa, ja sen prosessointi on työläämpää. NoSQL-tietokannat ovatkin nousseet perinteisten SQL-tietokantojen rinnalle tarjoamaan vaihtoehtoisia ratkaisuja nykypäivän haasteiden ratkaisemiseksi. Tutkielmassa tarkastellaan tietokantojen suorituskykyeroja käymällä läpi jo tehtyjä tutkimuksia aihealueesta, sekä pohditaan ovatko NoSQL-tietokannat valmiita käytettäviksi. SQL databases has been used almost since databases were invented. Nowadays there is a lot more data than before, it is more diverse, and processing it requires more work. NoSQL databases have risen to…
Mental Skills of an Athlete as a Resource of Professional Longevity in Sport
2021
The aim of the study was to assess associations between dimensions of mental skills, psychological readiness and predictors of career longevity among current athletes. Mental skills dimensions were measured with the Ottawa Mental Skills Assessment Tool (OMSAT). The psychological predictors of athletic career longevity were measured with the Athletic Coping Skills Scale-28 (the ACSI-28) producing scores for seven coping skills and with the Competitive State Anxiety Inventory-2 (CSAI-2) which produced scores for confidence in competition. Overall, 253 current athletes (average age 22 years) of various competitive levels (classified to 5 groups according to the national sport classification sy…
Beeta-alaniinin nauttimisen vaikutukset veren pH- ja laktaattiarvoihin sekä fyysiseen suorituskykyyn
2008
Saltevo, Saana Sinikka. Liikuntafysiologian kandidaattitutkielma. Kesä 2008. Beeta- alaniinin nauttimisen vaikutukset veren pH- ja laktaattiarvoihin sekä fyysiseen suorituskykyyn. 41 s. Beeta-alaniini muodostaa lihaskudoksessa karnosiinia, joka on lihaksen tärkeimpiä puskureita. Korkeaintensiteettisessä suorituksessa lihaksen pH:n laskun minimointi saattaisi olla hyödyksi lihassupistuksen optimaalisen toiminnan kannalta. Tämän tutkimuksen tarkoituksena oli selvittää vaikuttaako beeta-alaniini veren happamuuteen, laktaattiin ja fyysiseen suorituskykyyn. Tutkimukseen osallistui viisitoista jyväskyläläistä miesjalkapalloilijaa (21.3 ± 2.8 v.). Koehenkilöt jaettiin kahteen ryhmään, joista toise…
Thiol-Stabilized Atomically Precise, Superatomic Silver Nanoparticles for Catalyzing Cycloisomerization of Alkynyl Amines
2018
Abstract Both the electronic and surface structures of metal nanomaterials play critical roles in determining their chemical properties. However, the non-molecular nature of conventional nanoparticles makes it extremely challenging to understand the molecular mechanism behind many of their unique electronic and surface properties. In this work, we report the synthesis, molecular and electronic structures of an atomically precise nanoparticle, [Ag206L72]q (L = thiolate, halide; q = charge). With a four-shell Ag7@Ag32@Ag77@Ag90 Ino-decahedral structure having a nearly perfect D5h symmetry, the metal core of the nanoparticle is co-stabilized by 68 thiolate and 4 halide ligands. Both electroche…
Flat-band superconductivity in strained Dirac materials
2016
We consider superconducting properties of a two-dimensional Dirac material such as graphene under strain that produces a flat band spectrum in the normal state. We show that in the superconducting state, such a model results in a highly increased critical temperature compared to the case without the strain, inhomogenous order parameter with two-peak shaped local density of states and yet a large and almost uniform and isotropic supercurrent. This model could be realized in strained graphene or ultracold atom systems and could be responsible for unusually strong superconductivity observed in some graphite interfaces and certain IV-VI semiconductor heterostructures.
Supernova-neutrino induced reactions on molybdenum via neutral-currents
2012
In this thesis which consists of an introductory part and six publications the neutralcurrent neutrino-nucleus scatterings o the stable molybdenum nuclei are studied using microscopic nuclear models. The main focus is on supernova neutrinos and the nuclear responses to them for the aforementioned nuclei are computed by folding the computed cross sections with realistic neutrino-energy spectra. In this work both the coherent and incoherent contributions to the cross sections are considered. The contributions from the prominent multipole channels to the incoherent cross sections are also discussed in great detail.
Rozpoznawanie indywidualnych potrzeb edukacyjnych i wspieranie rozwoju uczniów w wieku wczesnoszkolnym z trudnościami w uczeniu się matematyki
2018
Coupling the Higgs mode and ferromagnetic resonance in spin-split superconductors with Rashba spin-orbit coupling
2022
We show that the Higgs mode of superconductors can couple with spin dynamics in the presence of a static spin-splitting field and Rashba spin-orbit coupling. The Higgs-spin coupling dramatically modifies the spin susceptibility near the superconducting critical temperature and consequently enhances the spin pumping effect in a ferromagnetic insulator/superconductor bilayer system. We show that this effect can be detected by measuring the magnon transmission rate and the magnon-induced voltage generated by the inverse spin Hall effect.
Topological polarization, dual invariants, and surface flat band in crystalline insulators
2020
We describe a three-dimensional crystalline topological insulator (TI) phase of matter that exhibits spontaneous polarization. This polarization results from the presence of (approximately) flat bands on the surface of such TIs. These flat bands are a consequence of the bulk-boundary correspondence of polarized topological media, and contrary to related nodal line semimetal phases also containing surface flat bands, they span the entire surface Brillouin zone. We also present an example Hamiltonian exhibiting a Lifshitz transition from the nodal line phase to the TI phase with polarization. Utilizing elasticity tetrads, we show a complete classification of 3D crystalline TI phases and invar…