980 resultados para unconventional superconductivity


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Drawing on the newest findings of politeness research, this paper proposes an interactionally grounded approach to computer-mediated discourse (CMD). Through the analysis of naturally occurring text-based synchronous interactions of a virtual team the paper illustrates that the interactional politeness approach can account for linguistic phenomena not yet fully explored in computer-mediated discourse analysis. Strategies used for compensating for the lack of audio-visual information in computer-mediated communication, strategies to compensate for the technological constraints of the medium, and strategies to aid interaction management are examined from an interactional politeness viewpoint and compared to the previous findings of CMD analysis. The conclusion of this preliminary research suggests that the endeavour to communicate along the lines of politeness norms in a work-based virtual environment contradicts some of the previous findings of CMD research (unconventional orthography, capitalization, economizing), and that other areas (such as emoticons, backchannel signals and turn-taking strategies) need to be revisited and re-examined from an interactional perspective to fully understand how language functions in this merely text-based environment.

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Tin oxide is considered to be one of the most promising semiconductor oxide materials for use as a gas sensor. However, a simple route for the controllable build-up of nanostructured, sufficiently pure and hierarchical SnO2 structures for gas sensor applications is still a challenge. In the current work, an aqueous SnO2 nanoparticulate precursor sol, which is free of organic contaminants and sorbed ions and is fully stable over time, was prepared in a highly reproducible manner from an alkoxide Sn(OR)4 just by mixing it with a large excess of pure neutral water. The precursor is formed as a separate liquid phase. The structure and purity of the precursor is revealed using XRD, SAXS, EXAFS, HRTEM imaging, FTIR, and XRF analysis. An unconventional approach for the estimation of the particle size based on the quantification of the Sn-Sn contacts in the structure was developed using EXAFS spectroscopy and verified using HRTEM. To construct sensors with a hierarchical 3D structure, we employed an unusual emulsification technique not involving any additives or surfactants, using simply the extraction of the liquid phase, water, with the help of dry butanol under ambient conditions. The originally generated crystalline but yet highly reactive nanoparticles form relatively uniform spheres through self-assembly and solidify instantly. The spheres floating in butanol were left to deposit on the surface of quartz plates bearing sputtered gold electrodes, producing ready-for-use gas sensors in the form of ca. 50 μm thick sphere-based-films. The films were dried for 24 h and calcined at 300°C in air before use. The gas sensitivity of the structures was tested in the temperature range of 150-400°C. The materials showed a very quickly emerging and reversible (20-30 times) increase in electrical conductivity as a response to exposure to air containing 100 ppm of H2 or CO and short (10 s) recovery times when the gas flow was stopped.

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Permanent magnet synchronous motors (PMSMs) provide a competitive technology for EV traction drives owing to their high power density and high efficiency. In this paper, three types of interior PMSMs with different PM arrangements are modeled by the finite element method (FEM). For a given amount of permanent magnet materials, the V shape interior PMSM is found better than the U-shape and the conventional rotor topologies for EV traction drives. Then the V shape interior PMSM is further analyzed with the effects of stator slot opening and the permanent magnet pole chamfering on cogging torque and output torque performance. A vector-controlled flux-weakening method is developed and simulated in matlab to expand the motor speed range for EV drive system. The results show good dynamic and steady-state performance with a capability of expanding speed up to 4 times of the rated. A prototype of the V shape interior PMSM is also manufactured and tested to validate the numerical models built by the finite element method.

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Economic theories of rational addiction aim to describe consumer behavior in the presence of habit-forming goods. We provide a biological foundation for this body of work by formally specifying conditions under which it is optimal to form a habit. We demonstrate the empirical validity of our thesis with an in-depth review and synthesis of the biomedical literature concerning the action of opiates in the mammalian brain and their eects on behavior. Our results lend credence to many of the unconventional behavioral assumptions employed by theories of rational addiction, including adjacent complementarity and the importance of cues, attention, and self-control in determining the behavior of addicts. We oer evidence for the special case of the opiates that "harmful" addiction is the manifestation of a mismatch between behavioral algorithms encoded in the human genome and the expanded menu of choices faced by consumers in the modern world.

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Az alsó kamatkorlát melletti előretekintő iránymutatás a kamatpolitika helyettesítője, a várakozások és a pénzpiaci hozamok befolyásolásának nem konvencionális monetáris politikai eszköze. A jegybank a piaci szereplők számára előre jelezheti az alacsony kamatkörnyezet tartós fennmaradását (delphoi típus), és kötelezettséget is vállalhat erre (odüsszeuszi típus). Ez utóbbi esetben megváltozik a jegybanki reakciófüggvény: a jegybanki kamatdöntésekben nem az inflációs kilátások és az inflációs cél közötti eltérés, illetve a kibocsátási rés jut kitüntetett szerephez, hanem valamilyen állapotváltozó alakulása vagy az időtényező. A reakciófüggvény változásának hitelessége esetén a hozamok csökkenésére lehet számítani. Ha a jegybank a kamatszint fenntartásának feltételéül az állapotváltozók olyan értékeit jelöli meg, amelyek teljesülése esetén az inflációs célkövetés szabályai szerint amúgy sem emelt volna kamatot, akkor az előretekintő iránymutatás „üres beszéd”, és a hozamokra gyakorolt hatás is elmaradhat. Egyelőre nem eldönthető, hogy az előretekintő iránymutatás a kamatpolitika átmeneti helyettesítőjéből annak tartós kiegészítő elemévé válik-e. _____ Forward guidance is a substitute for interest-rate policy where the zero lower boundary applies. It is an unconventional monetary policy instrument intended to influence market yields and expectations. The central bank may give signals (forecasts) to the market on lasting maintenance of a low interest-rate environment (Delphi type) or may commit itself to do so (Odysseus type). In the latter case the reaction function changes: instead of inflation prospects and output gap, the main role in central bank rate decisions becomes the evolution of given macroeconomic state variables or the time factor. If changes of the reaction function are credible, a drop in security yields are expected. Forward guidance is just cheap talk if such values in economic state variables are set as conditions for keeping interest rates unchanged, which based on the rules of inflation targeting would not trigger an interest rate increase, regardless. In that case, no impact on yields may occur. For the time being it cannot be decided whether forward guidance is transitory or a lasting instrument of monetary policy.