860 resultados para HOT FLASHES
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We revisit the issue of sensitivity to initial flow and intrinsic variability in hot-Jupiter atmospheric flow simulations, originally investigated by Cho et al. (2008) and Thrastarson & Cho (2010). The flow in the lower region (~1 to 20 MPa) `dragged' to immobility and uniform temperature on a very short timescale, as in Liu & Showman (2013), leads to effectively a complete cessation of variability as well as sensitivity in three-dimensional (3D) simulations with traditional primitive equations. Such momentum (Rayleigh) and thermal (Newtonian) drags are, however, ad hoc for 3D giant planet simulations. For 3D hot-Jupiter simulations, which typically already employ strong Newtonian drag in the upper region, sensitivity is not quenched if only the Newtonian drag is applied in the lower region, without the strong Rayleigh drag: in general, both sensitivity and variability persist if the two drags are not applied concurrently in the lower region. However, even when the drags are applied concurrently, vertically-propagating planetary waves give rise to significant variability in the ~0.05 to 0.5 MPa region, if the vertical resolution of the lower region is increased (e.g. here with 1000 layers for the entire domain). New observations on the effects of the physical setup and model convergence in ‘deep’ atmosphere simulations are also presented.
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Northeast Asia experienced a severe drought in summer 2014. Sea surface temperature forcing may have increased the risk of low precipitation, but model biases preclude reliable attribution to anthropogenic forcing.
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The essay uncovers evidence for the construction of the ‘woman author’ in the largely male vogue for bawdy burlesque poetry by tracing the circulation of a pair of verses through seventeenth-century manuscript and print miscellanies. It argues that just as these verses are reworked and recontextualised through the process of transmission, so to their ‘authors’ are re-embodied and ascribed different identities in different publication contexts. Female-voiced bawdy poetry raises particular problems for authorial attribution, rather than searching for the real woman behind the text, the essay examines how the ‘authors’ of female-voiced bawdy poetry were produced and reproduced through shifting formal frameworks and socioliterary networks.
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Sprites have been detected in video camera observations from Niger over mesoscale convective systems in Nigeria during the 2006 AMMA (African Monsoon Multidisciplinary Analysis) campaign The parent lightning flashes have been detected by multiple Extremely Low Frequency (ELF) receiving stations worldwide The recorded charge moments of the patent lightning flashes are often in excellent agreement between different receiving sites, and are furthermore consistent with conventional dielectric breakdown in the mesosphere as the origin of the sprites Analysis of the polarization of the horizontal magnetic field at the distant receivers provides evidence that the departure from linear magnetic polarization at ELF is caused primarily by the clay night asymmetry of the Earth-ionosphere cavity Copyright (C) 2009 Royal Meteorological Society
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Alfven eigenmodes (AE) driven by ion cyclotron resonance heating are usually registered by different diagnostic channels in the hot core plasmas of large tokamaks like JET and ASDEX Upgrade. These AE appear very near to the extremum points of Alfven wave continuum, which is modified by the geodesic effect due to poloidal mode coupling. It is shown that the AE spectrum may be explored as the magnetic spectroscopy (like Alfven cascades by Sharapov et al 2001 Phys. Lett. A 289 127) to determine the q-factor minimum and geodesic frequency at the magnetic axis in standard sawtoothed discharges without reversed shear.
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Assuming that nuclear matter can be treated as a perfect fluid, we study the propagation of perturbations in the baryon density. The equation of state is derived from a relativistic mean field model, which is a variant of the non-linear Walecka model. The expansion of the Euler and continuity equations of relativistic hydrodynamics around equilibrium configurations leads to differential equations for the density perturbation. We solve them numerically for linear and spherical perturbations and follow the propagation of the initial pulses. For linear perturbations we find single soliton solutions and solutions with one or more solitons followed by ""radiation"". Depending on the equation of state a strong damping may occur. We consider also the evolution of perturbations in a medium without dispersive effects. In this case we observe the formation and breaking of shock waves. We study all these equations also for matter at finite temperature. Our results may be relevant for the analysis of RHIC data. They suggest that the shock waves formed in the quark gluon plasma phase may survive and propagate in the hadronic phase. (C) 2009 Elseiver. B.V. All rights reserved.
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Assuming that nuclear matter can be treated as a perfect fluid, we study the propagation of perturbations in the baryon density at high temperature. The equation of state is derived from the non-linear Walecka model. The expansion of the Euler and continuity equations of relativistic hydrodynamics around equilibrium configurations lead to the breaking wave equation for the density perturbation. We solve it numerically for this perturbation and follow the propagation of the initial pulses.
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The Ibituruna quartz-syenite was emplaced as a sill in the Ribeira-Aracuai Neoproterozoic belt (Southeastern Brazil) during the last stages of the Gondwana supercontinent amalgamation. We have measured the Anisotropy of Magnetic Susceptibility (AMS) in samples from the Ibituruna sill to unravel its magnetic fabric that is regarded as a proxy for its magmatic fabric. A large magnetic anisotropy, dominantly due to magnetite, and a consistent magnetic fabric have been determined over the entire Ibituruna massif. The magmatic foliation and lineation are strikingly parallel to the solid-state mylonitic foliation and lineation measured in the country-rock. Altogether, these observations suggest that the Ibituruna sill was emplaced during the high temperature (similar to 750 degrees C) regional deformation and was deformed before full solidification coherently with its country-rock. Unexpectedly, geochronological data suggest a rather different conclusion. LA-ICP-MS and SHRIMP ages of zircons from the Ibituruna quartz-syenite are in the range 530-535 Ma and LA-ICP-MS ages of zircons and monazites from synkinematic leucocratic veins in the country-rocks suggest a crystallization at similar to 570-580 Ma, i.e., an HT deformation >35My older than the emplacement of the Ibituruna quartz-syenite. Conclusions from the structural and the geochronological studies are therefore conflicting. A possible explanation arises from (40)Ar-(39)Ar thermochronology. We have dated amphiboles from the quartz-syenite, and amphiboles and biotites from the country-rock. Together with the ages of monazites and zircons in the country-rock, (40)Ar-(39)Ar mineral ages suggest a very low cooling rate: <3 degrees C/My between 570 and similar to 500 Ma and similar to 5 degrees C/My between 500 and 460 Ma. Assuming a protracted regional deformation consistent over tens of My, under such stable thermal conditions the fabric and microstructure of deformed rocks may remain almost unchanged even if they underwent and recorded strain pulses separated by long periods of time. This may be a characteristic of slow cooling ""hot orogens"" that rocks deformed at significantly different periods during the orogeny, but under roughly unchanged temperature conditions, may display almost indiscernible microstructure and fabric. (C) 2009 Elsevier B.V. All rights reserved.
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Helstångsborr och konstång kallas bergborrverktyg, som tillverkas av sexkantiga stänger med inre hål för ledning av spolvatten. Dessa spolhål är klädda med ferritiskt rostfritt stål. Innan valsning borras ett centrerat hål i stålämnet som ska valsas. I det borrade hålet appliceras ett rör av ferritiskt rostfritt stål och i det röret skjuts en manganstålskärna in. Efter valsning dras kärnan ut och ett spolhål med invändigt foder av rostfritt stål bildas. Under uppvärmningen och valsningen av stålämnet sker normalt en koldiffusion från manganstålskärnan till det rostfria fodret. Fodrets syfte är att skydda spolhålets yta mot erosion och korrosion.Syftet med arbetet var att hitta en metod som garanterar uppkolning av det invändiga fodret, samt att utreda vad uppkolningen betyder för den mekaniska hållfastheten i stängerna. Ett laboratorieförsök visade att det var bra, med avseende på uppkolning, att blanda stearat i kärnbestrykningsmedlet. Kärnbestrykningsmedlet penslas på manganstålskärnan innan den förs in i stålämnet som ska valsas, dess syfte är att minska friktionen vid kärnutdragningen efter valsning.Ett försök utfördes i valsverket med stearat i kärnbestrykningsmedlet. En grundlig undersökning utfördes på två hetor som valsats med stearat-bestrykningsmedel, samt på en traditionellt tillverkad heta för att ha som referens. Hetorna kapades till provstänger om 1,5 m, totalt undersöktes 55 st.Utvärderingen av verksförsöket visade att stängernas kvalitet blir tillräckligt bra om ingenting oförutsett händer i produktionen, oavsett om koltillskott är tillsatt i bestrykningsmedlet eller inte. Arbetet gav inte en garanterande metod, men visade att stängerna normalt håller hög kvalitet.
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Syftet med denna systematiska litteraturstudie var att beskriva faktorer som påverkade uppkomsten av hot och våld inom psykiatrin. Till resultatet har författarna använt sig av tjugoen vetenskapliga artiklar som hämtats ur Högskolan dalarnas databaser ELIN, Academic Search Elite samt Cinahl. Sökord i olika kombinationer har använts för att få fram relevant litteratur till studien. De sökord som användes var violence, nursing, mental health nurses, aggressive patients, aggressive behaviour, psychiatric units, patients, factors, prevention, aggression, nurses, psychiatric, management, psychiatry och causes. Även manuell sökning i tidskrifter har gjorts. Artiklarna skulle vara publicerade tidigast år 2000 om inte tidigare studier ansågs innehålla relevant fakta för studien. Granskning av artiklarna genomfördes med hjälp av granskningsmallar. Resultatet visade att bemötandet av patienter inom psykiatrisk vård var av stor betydelse för om hotfulla och våldsamma incidenter skulle inträffa. Att som vårdpersonal försöka förstå anledningen till den uppkomna situationen kunde leda till att dessa situationer kunde undvikas. Patienterna upplevde ofta att personalen inte lyssnade och detta var en vanlig orsak till att våldsamma incidenter uppstod. Vårdpersonalen ansåg istället att patientens sjukdom var orsaken till uppkomsten av hot och våld. På avdelningar där patienter med paranoida och psykotiska tendenser var intagna ökade risken för våldsamma situationer. Patienterna upplevde ofta tiden på den psykiatriska avdelningen som långtråkig och det påverkade stämningen. Både vårdpersonal och patienter ansåg att mer aktiviteter skulle minska aggressionen på avdelningen.
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Inom friidrottens löpgrenar kan man idag se vid de stora galorna att det finns en person som har till uppgift att springa före övriga deltagare och springa i en viss fart som har beställts antingen av arrangörerna eller någon löpare. Denna person kallas för "hare" vars huvuduppgift är att se till att ett visst tempo hålls under loppet. Men vad har detta fenomen för effekt på idrottens värde? Detta arbete ger en beskrivning av fenomenet "haren" både ur historiskt perspektiv samt hur det ser ut i nutida läge. Genom diverse teorier om vad som skapar värde inom idrott och hur idrott bör utföras för att uppfattas som mer "äkta" har fenomenet sedan analyserats för att bestämma om fenomenet är något positivt eller negativt för idrottens värde. Prestationer är något som ska genomföras på egen hand och idrottaren skall besitta de resurser som krävs för att kunna genomföra ett lopp helt på egen hand och kunna hantera både interna och externa påfrestningar. Att inte veta vem som kommer att vinna är den ovisshet som skapar spänning och därmed värde inom idrott. Med haren har man eliminerat denna ovisshet för att i stället få spänning genom att fokusera loppen på att slå rekord. Detta sätt att skapa prestationer har en mycket negativ påverkan på idrottens värde vilket får en detaljerad analys i detta arbete.
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Hot rolling process is heat input process. The heat energy in hot rolled steel coils can be utilized. At SSAB Strip Product Borlänge when the hot rolled steel coils came out of the hot rolling mill they are at the temperature range of 500°C to 800°C. Heat energy contained by the one hot rolled steel coil is about 1981Kwh whereas the total heat energy for the year 2008 is 230 GWh/year.The potential of heat is too much but the heat dissipation rate is too slow. Different factors on which heat dissipation rate depends are discussed.Three suggestions are proposed to collect the waste heat from hot rolled steel coils.The 2nd proposal in which water basin is suggested would help not only to collect the waste heat but to decrease in the cooling time.
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2004, the SSR, Akademikerförbundet, made a study on the threats and violence as a social secretary in the municipal social services are exposed in their occupation of the "social secretary of threats and violence at work" (T-110192), conducted by Temo ab. We have chosen to use the study on a smaller scale and then made contact with five municipalities in the middle of Sweden to investigate social secretaries experiences of threats and violence. Using the cross-sectional design and a convenience sample, we have gained access to data from 56 people. From a sociological perspective, we have chosen to use Norbert Elias theory of universal configuration and interdependence, and Michel Foucault’s theories concerning power search explanation for the existence of threats and violent situations in the contact between social workers and their clients.
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Using a physically based model, the microstructural evolution of Nb microalloyed steels during rolling in SSAB Tunnplåt’s hot strip mill was modeled. The model describes the evolution of dislocation density, the creation and diffusion of vacancies, dynamic and static recovery through climb and glide, subgrain formation and growth, dynamic and static recrystallization and grain growth. Also, the model describes the dissolution and precipitation of particles. The impeding effect on grain growth and recrystallization due to solute drag and particles is accounted for. During hot strip rolling of Nb steels, Nb in solid solution retards recrystallization due to solute drag and at lower temperatures strain-induced precipitation of Nb(C,N) may occur which effectively retard recrystallization. The flow stress behavior during hot rolling was calculated where the mean flow stress values were calculated using both the model and measured mill data. The model showed that solute drag has an essential effect on recrystallization during hot rolling of Nb steels.
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The surface failure characteristics of different work roll materials, i.e. High Speed Steel, High Chromium Iron and Indefinite Chill Iron, used in the finishing stands of a hot strip mill have been investigated using stereo microscopy, 3D optical profilometry, scanning electron microscopy and energy dispersive X-ray spectroscopy. The results show that the surface failure mechanisms of work rolls for hot rolling are very complex, involving plastic deformation, abrasive wear, adhesive wear, mechanical and thermal induced cracking, material transfer and oxidation. Despite the differences in chemical composition and microstructure, the tribological response of the different work roll materials was found to be strongly dependent on the material microstructure and especially the presence and distribution of microstructural constituents, such as the different carbide phases and graphite (in the case of Indefinite Chill Iron). Cracking and chipping of the work roll surfaces, both having a negative impact on work roll wear, are strongly influenced by the presence of carbides, carbide networks and graphite in the work roll surface. Consequently, the amount of carbide forming elements as well as the manufacturing process must be controlled in order to obtain an optimised microstructure and a predictable wear rate.