940 resultados para Disciplinary regime
Resumo:
Since the disintegration of the Soviet Union, Cuba has experienced a severe economic crisis, and the country's social policy has played an important role in showing the people a raison-d'etre for the revolution. This role has become even stronger in recent years, as internal and external actors demand political reforms and economic liberalization. This article first examines the Cuban government's use of social development to counter the demands for changes. It then looks at the extent that government social policy contributes economically to improving the Cuban living standard. The article demonstrates empirically how the leadership emphasizes their social accomplishments whenever demands for change come, and then shows that after the suspension of Soviet aid, Cuban social policy has been able to provide services mainly by relying on human capital and reducing quality materially because of the shortage of foreign reserves. This has limited the economic effectiveness of the services.
Resumo:
The ensuing bloodshed and deteriorating humanitarian crisis in Syria, the failure of the United Nations Security Council to reach a consensus on what action to take, and the involvement of contending external actors partially reflect the complexity of the current impasse. Despite the importance of regional and international factors, however, this papers attempts to argue that the domestic dynamics of the Syrian crisis have been vitally important in determining the course of the popular uprising and the regime’s response. In this, Syria’s crisis belongs with the Arab Spring the trajectories and prospects of which have been shaped by dynamics within regimes. It will be seen that the formal and informal institutional structure of the Ba‘thist regime in Syria has been critical to its resilience and ability to stay united so far while attempting to crush a peaceful popular uprising that turned into insurgency in the face of the regime’s violent crackdown.
Resumo:
エジプトではムバーラク大統領の国内政策と域内におけるエジプトの影響力低迷が引き金となって、2011年1月25日に抗議運動起こった。抗議運動はエジプト全土に拡がり、18日間の民衆的な反体制運動によってムバーラクは軍に見捨てられ、失脚に追い込まれた。この民衆蜂起によって警察は街頭から撤退し、シナイ半島の警察署は焼き放たれ、ムバーラクが率いていた国民民主党の建物や国内治安機関の本部は襲撃され、国家機関が数ヶ月にもわたって機能不全となり、ムバーラク体制の崩壊は国内的な混乱を招くこととなった。振り返れば、エジプトでの政治的大変動は社会的な革命へと展開することはできなかった。その理由は独裁体制からの移行を先導できる組織化された反体制勢力が存在しなかったためである。民衆による抗議運動は一時的に体制を転覆できても旧体制のエリートを分裂させることはできず、軍の影響下にある体制の復活を防ぐこともできなかった。2011年以降のエジプトは現在まで混乱状態に陥ったままであるが、1カ月に及ぶエジプト軍最高評議会(SCAF)の暫定統治、エジプト史上初の自由な大統領選挙によって選出された文民大統領のムルスィーによる一年余りの統治、そして2013年7月の軍事クーデターによって権力の座に就いたスィースィーの統治といった過程で、民衆蜂起がエジプトの外交関係に及ぼした影響はごく僅かであった。本稿は、現在のエジプトの外交政策が2011年の革命にほとんど影響を受けていないのはなぜか、またエジプトの統治者たちが政権の正統性、体制の強化および政治的な安定性を確保し、国内的な課題に対処するための戦略をいかに策定しているのかを説明することを試みる。本稿での主張は、ムバーラク以降のエジプトが体制の強化と保全のために外交政策を進めており、国内的な混乱によって地域内アクターへの依存度が高まっていることである。
Resumo:
An earlier analysis of the Hall-magnetohydrodynamics (MHD) tearing instability [E. Ahedo and J. J. Ramos, Plasma Phys. Controlled Fusion 51, 055018 (2009)] is extended to cover the regime where the growth rate becomes comparable or exceeds the sound frequency. Like in the previous subsonic work, a resistive, two-fluid Hall-MHD model with massless electrons and zero-Larmor-radius ions is adopted and a linear stability analysis about a force-free equilibrium in slab geometry is carried out. A salient feature of this supersonic regime is that the mode eigenfunctions become intrinsically complex, but the growth rate remains purely real. Even more interestingly, the dispersion relation remains of the same form as in the subsonic regime for any value of the instability Mach number, provided only that the ion skin depth is sufficiently small for the mode ion inertial layer width to be smaller than the macroscopic lengths, a generous bound that scales like a positive power of the Lundquist number
Resumo:
The one-dimensional self-similar motion of an initially cold, half-space plasma of electron density 0,produced by the (anomalous) absorption of a laser pulse of irradiation
Resumo:
Thermal smoothing in the plasma ablated from a laser target under weakly nonuniform irradiation is analyzed, assuming absorption at nc and a deflagration regime (conduction restricted to a thin quasisteady layer next to the target). Magnetic generation effects are included and found to be weak. Differences from results available in the literature are explained; the importance of the character of the underdense flow at uniform irradiation is emphasized.
Resumo:
Refractive smoothing of weak non-uniformities in the illumination of laser targets is analyzed, assuming absorption at the critical density and restricting conduction to a thin layer, and using results from thermal smoothing, which is uncoupled from the refraction. Magnetic effects are included. Non-uniformity wavelengths comparable to the thickness of the conduction layer are considered; efficient smoothing exists at both short and long wavelengths in this range. Thermal focusing could make the ablated plasma unstable.
Resumo:
An asymptotic analysis of electron collection at high bias Fp serves to determine the domain of validity of the orbital-motion-limited regime of cylindrical Langmuir probes, which is basic for the workings of conductive bare tethers. The radius of a wire collecting OML current in an unmagnetized plasma at rest cannot exceed a value, Rmax , which is found to exhibit a minimum as a function of Fp ; atFp values of interest, Rmax is already increasing and is larger than the electron Debye length lDe . The breakdown of the regime relates to conditions far fromthe probe, at electron energies comparable to the ion thermal energy, kTi ; Rmax is found to increase with Ti . It is also found that ~1! the maximumwidth of a thin tape, if used instead of a wire, is 4Rmax ; ~2! the electron thermal gyroradius must be larger than both R and lDe for magnetic effects to be negligible; and ~3! conditions applying to the tether case are such that trapped-orbit effects are negligible.
Resumo:
The current I to a cylindrical probe at rest in an unmagnetized plasma, with probe bias highly positive, is determined. The way I lags behind the orbital-motion-limited OMLcurrent, 1 OML R, as the radius R exceeds the maximum radius for the OML regime to hold, is of interest for space-tether applications. The ratio I/I OML is roughly a decreasing function of R/lD R max /lDe , which is independent of bias, with lDe the electron Debye length and Rmax /l De roughly an increasing function of the temperature ratio, Ti /Te. The dependence of current on ion energy is used to discuss the effect of probe motion through the plasma, a case applying to tethers in low orbit.
Resumo:
In this work the spectrally resolved, multigroup and mean radiative opacities of carbon plasmas are calculated for a wide range of plasma conditions which cover situations where corona, local thermodynamic and non-local thermodynamic equilibrium regimes are found. An analysis of the influence of the thermodynamic regime on these magnitudes is also carried out by means of comparisons of the results obtained from collisional-radiative, corona or Saha–Boltzmann equations. All the calculations presented in this work were performed using ABAKO/RAPCAL code.
Resumo:
The determination of the plasma potential Vpl of unmagnetized plasmas by using the floating potential of emissive Langmuir probes operated in the strong emission regime is investigated. The experiments evidence that, for most cases, the electron thermionic emission is orders of magnitude larger than the plasma thermal electron current. The temperature-dependent floating potentials of negatively biased Vpmenor queVpl emissive probes are in agreement with the predictions of a simple phenomenological model that considers, in addition to the plasma electrons, an ad-ditional electron group that contributes to the probe current. The latter would be constituted by a fraction of the repelled electron thermionic current, which might return back to the probe with a different energy spectrum. Its origin would be a plasma potential well formed in the plasma sheath around the probe, acting as a virtual cathode or by collisions and electron thermalization pro-cesses. These results suggest that, for probe bias voltages close to the plasma potential Vp?Vpl, two electron populations coexist, i.e., the electrons from the plasma with temperatureTeand a large group of returned thermionic electrons. These results question the theoretical possibility of measuring the electron temperature by using emissive probes biased to potentials Vp about lower equal than ?Vpl.