6 resultados para U.S Foreign Relations 2000-2009
em CentAUR: Central Archive University of Reading - UK
Resumo:
Magnetic clouds are a subset of interplanetary coronal mass ejections characterized by a smooth rotation in the magnetic field direction, which is interpreted as a signature of a magnetic flux rope. Suprathermal electron observations indicate that one or both ends of a magnetic cloud typically remain connected to the Sun as it moves out through the heliosphere. With distance from the axis of the flux rope, out toward its edge, the magnetic field winds more tightly about the axis and electrons must traverse longer magnetic field lines to reach the same heliocentric distance. This increased time of flight allows greater pitch-angle scattering to occur, meaning suprathermal electron pitch-angle distributions should be systematically broader at the edges of the flux rope than at the axis. We model this effect with an analytical magnetic flux rope model and a numerical scheme for suprathermal electron pitch-angle scattering and find that the signature of a magnetic flux rope should be observable with the typical pitch-angle resolution of suprathermal electron data provided ACE's SWEPAM instrument. Evidence of this signature in the observations, however, is weak, possibly because reconnection of magnetic fields within the flux rope acts to intermix flux tubes.
Resumo:
In this paper, we are concerned with the provision of schools in rural North India, particularly with whether such provision is determined by the demographic and economic characteristics of the region or whether local democracy also plays a role. We find that the probability that a governing party loses an election has a positive effect on the provision of schooling infrastructure, while the margin of victory of the governing party has a negative effect. Political reservation for members of the Scheduled Castes (SCs) has a positive effect on schooling infrastructure in villages with a large SC population, but a negative effect overall.
Resumo:
A quantitative assessment of Cloudsat reflectivities and basic ice cloud properties (cloud base, top, and thickness) is conducted in the present study from both airborne and ground-based observations. Airborne observations allow direct comparisons on a limited number of ocean backscatter and cloud samples, whereas the ground-based observations allow statistical comparisons on much longer time series but with some additional assumptions. Direct comparisons of the ocean backscatter and ice cloud reflectivities measured by an airborne cloud radar and Cloudsat during two field experiments indicate that, on average, Cloudsat measures ocean backscatter 0.4 dB higher and ice cloud reflectivities 1 dB higher than the airborne cloud radar. Five ground-based sites have also been used for a statistical evaluation of the Cloudsat reflectivities and basic cloud properties. From these comparisons, it is found that the weighted-mean difference ZCloudsat − ZGround ranges from −0.4 to +0.3 dB when a ±1-h time lag around the Cloudsat overpass is considered. Given the fact that the airborne and ground-based radar calibration accuracy is about 1 dB, it is concluded that the reflectivities of the spaceborne, airborne, and ground-based radars agree within the expected calibration uncertainties of the airborne and ground-based radars. This result shows that the Cloudsat radar does achieve the claimed sensitivity of around −29 dBZ. Finally, an evaluation of the tropical “convective ice” profiles measured by Cloudsat has been carried out over the tropical site in Darwin, Australia. It is shown that these profiles can be used statistically down to approximately 9-km height (or 4 km above the melting layer) without attenuation and multiple scattering corrections over Darwin. It is difficult to estimate if this result is applicable to all types of deep convective storms in the tropics. However, this first study suggests that the Cloudsat profiles in convective ice need to be corrected for attenuation by supercooled liquid water and ice aggregates/graupel particles and multiple scattering prior to their quantitative use.
Resumo:
This article summarizes the main research findings from the first of a series of annual surveys conducted for the British Council of Shopping Centres. The study examines the changing pattern of retailing in the United Kingdom and provides an overview of key research from previous studies in both the U.K. and the United States. The main findings are then presented, including an examination of the impact of e-commerce on sales and rental values and on the future space and ownership / leasing requirements of U.K. retailers for 2000-2005. The impact on a shopping center in a case study town in the U.K. is also considered. The difficulties of isolating the impact of e-commerce from other forces for change in retailing are highlighted. In contrast to other viewpoints, the results show that e-commerce will not mean the death of conventional store-based U.K. retailing, although further benchmark research is needed.