920 resultados para Output gap


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In defining what he termed 'Television's Second Golden Age', Robert J.Thompson refers to characteristics such as being 'not regular TV', internal continuity, mixed genres but an aspiration towards 'realism', complex writing, self-consciousness and intertextuality. Such characteristics are displayed by the BBC series Life on Mars (2006-2007) which intermingles the Seventies tough cop show with psychological fantasy. This chapter examines the way that the series can be understood as a dramatisation of the negotiation that the creators undertook with their Seventies source material to update it for the values and qualities of contemporary television drama. It will emphasise the importance of television in the generation of the imagined 1973 and its characters, but also as an ongoing connection between the real and the imagined within the programme, including forming a breach of the boundaries between the two. Sam's actions within his Seventies world to remake it to include his own ideas of justice and due process while retaining the passion and freedom of action that the milieu provides will also be be examined in relation to the series' creators' needs to remake the Seventies tough-cop show in the light of modern social and media mores. The paper will also consider how Sam has to come to terms with his father's crimes, as the series' creators had to come to terms with the 'crimes' of taste, morality and approach of their 'parent' programmes from the Seventies' Golden Age.

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This chapter provides a critical assessment of the approach adopted by the United Nations Convention on the Rights of Persons with Disabilities (CRPD) towards children with disabilities and its implications for socializing States Parties to both ‘right’ and ‘rights’ behaviour. It discusses the ways in which ‘rights talk’ for children with disabilities, itself a relatively recent development in this context, has been predominantly needs based in its substantive content, and explores whether the exacerbated disadvantage experienced by children with disabilities as a result of the particular interaction between disability and childhood is effectively addressed and given due weight by the new Convention. The CRPD's provisions are discussed in the context of children with disabilities and their potential to provide effective redress assessed. The chapter concludes with some critical reflections on the extent to which the CRPD can really be understood as minding the gap for children with disabilities.

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We show that for a large class of exchange-correlation functionals the local exchange-correlation potential obtained within an optimized effective potential severely underestimates the band gap. On the other hand, the corresponding nonlocal potential obtained from a generalized Kohn-Sham scheme provides a much better description of the band gap, in good agreement with experiments. These results strongly indicate that a local exchange-correlation potential, however good the exchange-correlation approximation, cannot capture the delicate interplay between correlation effects and spatial localization in the KS band structure, unless the (cumbersome) contribution from the derivative discontinuity of the exchange-correlation energy functional is considered.

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Theoretically the Kohn-Sham band gap differs from the exact quasiparticle energy gap by the derivative discontinuity of the exchange-correlation functional. In practice for semiconductors and insulators the band gap calculated within any local or semilocal density approximations underestimates severely the experimental energy gap. On the other hand, calculations with an "exact" exchange potential derived from many-body perturbation theory via the optimized effective potential suggest that improving the exchange-correlation potential approximation can yield a reasonable agreement between the Kohn-Sham band gap and the experimental gap. The results in this work show that this is not the case. In fact, we add to the exact exchange the correlation that corresponds to the dynamical (random phase approximation) screening in the GW approximation. This accurate exchange-correlation potential provides band structures similar to the local density approximation with the corresponding derivative discontinuity that contributes 30%-50% to the energy gap. Our self-consistent results confirm substantially the results for Si and other semiconductors obtained perturbatively [R. W. Godby , Phys. Rev. B 36, 6497 (1987)] and extend the conclusion to LiF and Ar, a wide-gap insulator and a noble-gas solid. (c) 2006 American Institute of Physics.

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We present here a detailed study of the complex relationship between the electromagnetic near-field and far-field responses of "real" nanostructured metallic surfaces. The near-field and far-field responses are specified in terms of (spectra of) the surface-enhanced Raman-scattering enhancement factor (SERS EF) and optical extinction, respectively. First, it is shown that gold nanorod- and nanotube-array substrates exhibit three distinct localized surface plasmon resonances (LSPRs): a longitudinal, a transverse, and a cavity mode. The cavity mode simultaneously has the largest impact on the near-field behavior (as observed through the SERS EF) and the weakest optical interaction: It has a "near-field-type" character. The transverse and longitudinal modes have a significant impact on the far-field behavior but very little impact on SERS: They have a "far-field-type" character. We confirm the presence of the cavity mode using a combination of SERS EF spectra, electron microscopy, and electromagnetic modeling and thus clearly illustrate and explain the (lack of) correlation between the SERS EF spectra and the optical response in terms of the contrasting character of the three LSPRs. In doing so, we experimentally demonstrate that, for a surface that supports multiple LSPRs, the near-field and far-field properties can in fact be tuned almost independently. It is further demonstrated that small changes in geometrical parameters that tune the spectral location of the LPSRs can also drastically influence the character of these modes, resulting in certain unusual behavior, such as the far-field resonance redshift as the near-field resonance blueshifts. DOI: 10.1103/PhysRevX.3.011001

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A compact differential 4-way power combiner with 2.3 dB loss and high common-mode rejection characteristic for use in mm-wave PAs is presented. A complete circuit comprised of a power splitter, two-stage cascode PA array, and a power combiner was implemented in SiGe technology. Measured small-signal gain of at least 17 dB was obtained from 74.5 GHz to 80.5 GHz with a peak 21 dB at 79 GHz. The prototype delivered 13.2 dBm P1dB and 14.3 dBm Psat when operated from a single 3.3 V supply at 75 GHz.

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It has been argued that the variation in brain activity that occurs when observing another person reflects a representation of actions that is indivisible, and which plays out in full once the intent of the actor can be discerned. We used transcranial magnetic stimulation to probe the excitability of corticospinal projections to 2 intrinsic hand muscles while motions to reach and grasp an object were observed. A symbolic cue either faithfully indicated the required final orientation of the object and thus the nature of the grasp that was required, or was in conflict with the movement subsequently displayed. When the cue was veridical, modulation of excitability was in accordance with the functional role of the muscles in the action observed. If however the cue had indicated that the alternative grasp would be required, modulation of output to first dorsal interosseus was consistent with the action specified, rather than the action observed-until the terminal phase of the motion sequence during which the object was seen lifted. Modulation of corticospinal output during observation is thus segmented-it progresses initially in accordance with the action anticipated, and if discrepancies are revealed by visual input, coincides thereafter with that of the action seen.

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Cooling techniques play a key role in improving efficiency and power output of modern gas turbines. The conjugate technique of film and impingement cooling schemes is considered in this study. The Multi-Stage Cooling Scheme (MSCS) involves coolant passing from inside to outside turbine blade through two stages. The first stage; the coolant passes through first hole to internal gap where the impinging jet cools the external layer of the blade. Finally, the coolant passes through the internal gap to the second hole which has specific designed geometry for external film cooling. The effect of design parameters, such as, offset distance between two-stage holes, gap height, and inclination angle of the first hole, on upstream conjugate heat transfer rate and downstream film cooling effectiveness performance are investigated computationally. An Inconel 617 alloy with variable properties is selected for the solid material. The conjugate heat transfer and film cooling characteristics of MSCS are analyzed across blowing ratios of Br = 1 and 2 for density ratio, 2. This study presents upstream wall temperature distributions due to conjugate heat transfer for different gap design parameters. The maximum film cooling effectiveness with upstream conjugate heat transfer is less than adiabatic film cooling effectiveness by 24–34%. However, the full coverage of cooling effectiveness in spanwise direction can be obtained using internal cooling with conjugate heat transfer, whereas adiabatic film cooling effectiveness has narrow distribution.

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The purpose of this article is to identify some the most critical outstanding issues faced by practitioners in undertaking effective talent management. In spite of the global financial crisis, talent management will continue being one of the most important challenges faced by organizations in the coming decade. Workforce demographics and skills shortages are likely to make the "war for talent'' fiercer than ever before making effective talent management a competitive necessity. While talent management is rapidly developing as a research field, there are many areas and questions that need to be explored. These questions are likely to have a particularly important applied benefit as they represent some of the key challenges organizations are grappling with in effectively managing their talent. The article asks researchers in the field to consider the questions proposed in developing future research agendas.