497 research outputs found
Nonlinear Oscillations and Bifurcations in Silicon Photonic Microresonators
Silicon microdisks are optical resonators that can exhibit surprising
nonlinear behavior. We present a new analysis of the dynamics of these
resonators, elucidating the mathematical origin of spontaneous oscillations and
deriving predictions for observed phenomena such as a frequency comb spectrum
with MHz-scale repetition rate. We test predictions through laboratory
experiment and numerical simulation.Comment: Main text: 5 pages, 6 figures. Supplemental material: 12 pages, 8
figure
Regional distribution of the prostaglandin E2 receptor EP1 in the rat brain: accumulation in Purkinje cells of the cerebellum
Prostaglandin E2 (PGE2), is a major prostanoid produced by the activity of cyclooxygenases (COX) in response to various physiological and pathological stimuli. PGE2 exerts its effects by activating four specific E-type prostanoid receptors (EP1, EP2, EP3 and EP4). In the present study, we analyzed the expression of the PGE2 receptor EP1 (mRNA and protein) in different regions of the adult rat brain (hippocampus, hypothalamus, striatum, prefrontal cerebral cortex, parietal cortex, brain stem and cerebellum) using reverse transcription-polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical methods. On a regional basis, levels of EP1 mRNA were the highest in parietal cortex and cerebellum. At the protein level, we found a very strong expression of EP1 in cerebellum as revealed by Western blotting experiments. Furthermore, the present study provides for the first time evidence that the EP1 receptor is highly expressed in the cerebellum, where the Purkinje cells displayed a very high immunolabeling of their perikaryon and dendrites as observed in the immunohistochemical analysis. Results from the present study indicate that the EP1 prostanoid receptor is expressed in specific neuronal populations, which possibly determine the region specific response to PGE2
Wie viel Gesundheit wollen wir uns eigentlich leisten?
Der Gesetzlichen Gesundheitsversorgung in Deutschland stehen einschneidende Reformen bevor. Können das Konzept der Bürgerversicherung, der Vorschlag einer Gesundheitsprämie oder kapitalgedeckte Prämien eine Lösung bieten?
Hydraulic Press of Car Coolers
Import 05/08/2014Diplomová práce se zabývá návrhem hydraulického pohonu lisu automobilových chladičů. V úvodu je popsána historie a vývoj automobilových chladičů. Dále jsou zmapovány typy chladičů jejích výroba a možnost výroby na lisech. V další kapitole jsou uvedeny požadavky pro hydraulický lis. Na základě požadavků je vybráno jedno ze čtyř řešení, pro které jsou provedeny výpočty pro dílčí části hydraulického pohonu lisu. Dále jsou vyspecifikovány jednotlivé prvky hydraulického obvodu. Výrobní dokumentaci doplňuje zpracovaný 3D model hydraulického agregátu. Další kapitola se zabývá návodem na obsluhu a údržbu navrženého hydraulického zařízení. V závěru práce je pro toto zařízení vypracováno hodnocení rizik.Master thesis deals with hydraulic press of car coolers. In the introduction is described history and development of car coolers. Then are charted types of coolers, their production and possibilities of production on hydraulic press. In the next chapter are shown requirements for hydraulic press. Based on the requirements is selected one of the four solutions, for which are performed calculations for parts of hydraulic drive of press. Then are specified individual elements of hydraulic press drive. 3D model of the hydraulic circuit complete the product documentation. Next chapter deals with instructions for use and maintenance of the proposed hydraulic equipment. At the end of the thesis is carried out risk assessments for proposed equipment.338 - Katedra hydromechaniky a hydraulických zařízenídobř
Laser Peening für innovative Werkstoffe und Oberflächen
Laser peening (laser shock peening, LSP) is a mechanical surface treatment, increasingly applied for generating particularly deep residual compressive stresses close to the surface thus significantly increasing the service life of components. In order to meet the current challenges in the field of sustainability, this work investigates the enormous potential of this technology, from a materials science perspective, in the field of additive manufacturing / 3D printing for lifetime enhancement as well as surface functionalization. As an example, Ti6Al4V alloy, used for additively manufactured components for space applications, is used to demonstrate the introduction of 2.4 mm deep compressive residual stresses, leading to an increase in fatigue life by a factor 100, and also further explaining the deformation characteristics. A comparison is made with conventional shot peening and technically proven cast iron. Laser peening is used for the first time to overcome the near-surface tensile residual stresses typical in laser-based topographic functionalization and additionally opens the perspective for a multi-scale periodically structured surface. Laser polishing, direct laser interference patterning (DLIP) and laser peening will be presented as a novel process combination applied for the sustainable and tailored post-treatment of additively manufactured parts.Laser Peening (Laser Shock Peening, Laser Schock Verfestigung, LSP) repräsentiert ein zunehmend anwendungsrelevantes mechanisches Oberflächenbehandlungsverfahren zur Generierung besonders tiefer oberflächennaher Druck-Eigenspannungen für signifikante Lebensdauersteigerungen von Bauteilen. Um den aktuellen Herausforderungen im Bereich Nachhaltigkeit zu begegnen, untersucht die vorliegende Arbeit aus materialwissenschaftlicher Perspektive das enorme Potential dieser Technologie im Bereich additive Fertigung / 3D-Druck zur Lebensdauersteigerung sowie Oberflächenfunktionalisierung. Am Beispiel der für additiv gefertigte Bauteile in Weltraumanwendungen eingesetzten Legierung Ti6Al4V wird die Einbringung von 2,4 mm tiefen Druck-Eigenspannungen gezeigt, welche zu einer Steigerung der Lebensdauer um den Faktor 100 führen, sowie ein Beitrag zur Aufklärung der Deformationscharakteristik geleistet. Dabei erfolgt ein Vergleich zu konventionellem Kugelstrahlen und dem technisch bewährten Werkstoff Gusseisen. Laser Peening wird erstmals zur Überwindung der für laserbasierte topographische Funktionalisierungen typischen oberflächennahen Zug-Eigenspannungen genutzt und eröffnet die Perspektive für eine multiskalige, periodische Oberflächenstrukturierung. Die Verfahren Laserpolieren, direkter Laser-Interferenzstrukturierung (DLIP) und Laser Peening werden als neuartige Prozesskombination zur nachhaltigen und maßgeschneiderten Nachbehandlung additiv hergestellter Bauteile vorgestellt
Egzegeza Księgi Izajasza 61,1-11: historia redakcji i pytanie o tożsamość proroka zwanego Tritoizajaszem
Exegesis of Is 61 has shown that the chapter is a literal composition,which consists of two parts: a frame vv. 1-3+10-11 and a middle part vv.4-9. The two framing sections, vv.1-3(10-11) could first have been a separatetext. V. 3aa is possibly a secondary addition, which joins chapter 61 withchapters 60 and 62. But it is reasonable to read and interpret Is 61 as oneunit, in which a prophetic „I” take the floor. The „I” poses as a servantknown from Deutero-Isaiah’s Songs of JHWH’s Servant. But in this „I”we hear tradents who passed down and updated Deutero-Isaiah’s tradition,and added new God’s promises. The prophet Trito-Isaiah, who should belike the other prophets speaking to the people, never existed. However thetradents understood their mission as prophetical one
Hydraulic Drive of Stepping Conveyer
Import 03/08/2012Bakalářská práce se zabývá konstrukčním návrhem hydraulického pohonu krokového dopravníku pro 7 kusů tlakových láhví v jednom kroku. V úvodu je proveden rozbor použitelnosti dopravníků pro tlakové láhve. Krokový dopravník jednoznačně splňuje všechny zadané požadavky k přepravě tlakových lahví. Na základě provedeného rozboru je dále řešen kinematický návrh navrženého řešení. Následuje silový rozbor kinematického návrhu, který doplňují pevnostní výpočty. Poté jsou odhadnuty hydromotory, u kterých jsou uvedeny výpočty jejich tlaků a průtoků. Následně je navržen samotný agregát. Výsledkem je projekční řešení hydraulického pohonu s označením jednotlivých navržených prvků a konstrukční návrh krokového dopravníku.The bachelor thesis is dealing with the design of the construction of hydraulic drive
of stepping conveyor for 7 pieces cylinders in one step. In the introduction is analyzed
the applicability of conveyors for cylinders. Stepping conveyor clearly satisfies all
the stated requirements for transport of cylinders. Based on the analysis is solved kinematic design of the proposed solution. Follow kinematic analysis of power and strength calculations. Then are estimated hydraulic cylinders, where are calculations of pressures and flow rates. Then is design unit itself. The result is hydraulic drive design solutions
with designation of individual elements and construction design of stepping conveyor.338 - Katedra hydromechaniky a hydraulických zařízenívelmi dobř
CYCLONE Unified Deployment and Management of Federated, Multi-Cloud Applications
Various Cloud layers have to work in concert in order to manage and deploy
complex multi-cloud applications, executing sophisticated workflows for Cloud
resource deployment, activation, adjustment, interaction, and monitoring. While
there are ample solutions for managing individual Cloud aspects (e.g. network
controllers, deployment tools, and application security software), there are no
well-integrated suites for managing an entire multi cloud environment with
multiple providers and deployment models. This paper presents the CYCLONE
architecture that integrates a number of existing solutions to create an open,
unified, holistic Cloud management platform for multi-cloud applications,
tailored to the needs of research organizations and SMEs. It discusses major
challenges in providing a network and security infrastructure for the
Intercloud and concludes with the demonstration how the architecture is
implemented in a real life bioinformatics use case
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