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X. P. You G. Hobbs W. A. Coles R. N. Manchester R. Edwards M. Bailes J. Sarkissian J. P. W. Verbiest W. van Straten A. Hotan S. Ord F. Jenet N. D. R. Bhat A. Teoh 《Monthly notices of the Royal Astronomical Society》2007,378(2):493-506
We present an analysis of the variations seen in the dispersion measures (DMs) of 20-ms pulsars observed as part of the Parkes Pulsar Timing Array project. We carry out a statistically rigorous structure function analysis for each pulsar and show that the variations seen for most pulsars are consistent with those expected for an interstellar medium characterized by a Kolmogorov turbulence spectrum. The structure functions for PSRs J1045−4509 and J1909−3744 provide the first clear evidence for a large inner scale, possibly due to ion–neutral damping. We also show the effect of the solar wind on the DMs and show that the simple models presently implemented into pulsar timing packages cannot reliably correct for this effect. For the first time we clearly show how DM variations affect pulsar timing residuals and how they can be corrected in order to obtain the highest possible timing precision. Even with our presently limited data span, the residuals (and all parameters derived from the timing) for six of our pulsars have been significantly improved by correcting for the DM variations. 相似文献
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Choon-Hooi Teoh 《Advances in water resources》1982,5(4):208-216
Relatively rapid and reliable procedures are required to determine reservoir storage-yield relationships during preliminary studies or reconnaissance surveys associated with regional assessments of surface water resources. Several techniques are available, but all are limited in their application. The following eight procedures were evaluated: Hurst (empirical), Alexander (gamma), Gould (synthetic), Dincer, Gould (gamma), Hardison (carryover), Guglij and McMahon (empirical). Each procedure was evaluated by application to 33 Australian and 12 Malaysian streams. The storage estimates determined from the rapid procedures were compared with those from behaviour (or simulation) analysis and Gould's transition matrix method. Limitations in theoretical models result from the basic assumptions upon which they were developed. For empirical models, difficulties arise through the non-representativeness of the basic data. Some procedures are restricted in the range of conditions within which they are applicable. The results indicate that Gould's (gamma) and McMahon's (empirical) procedures provide satisfactory storage estimates for preliminary assessments. 相似文献
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ABSTRACTMitigating climate change is often framed as the ultimate collective action problem of this era and great emphasis is made on the need for approaches that foster ‘cooperation’ and ‘consensus’. This paper argues that the irony of this rhetoric could not be more stark; climate policy framing is an exclusionary process, and climate mitigating interventions that are engineered essentially to address neoliberal economic concerns rather than environmental challenges are often the source of multiple new conflicts. In this regard, this paper shows how the response of local non governmental organisations (NGOs) to hydropower development in the Darjeeling region of West Bengal in the Eastern Himalayas bears evidence to Gramscian analyses of ‘the manufacture of consent’ between elite bourgeois actors – the state, formal civil society, political parties and the private sector. Such ‘associational’ unions are only occasionally interrupted, as in the case of the people’s movement, Affected Citizens of Teesta (ACT) in North Sikkim. Finding a balance between resistance and enabling political space to think and act differently, the movement led to the cancellation of several hydropower projects put forward in the name of climate mitigation, and in the process, drew attention to political processes involved in the manufacture of consent. Using case studies from the Darjeeling and Sikkim regions, this paper distinguishes between Gramsci’s vision of the political space of disruption vis-à-vis the covert agenda of climate consensus.Key policy insights
A politics of consensus in relation to climate change is an outcome of, and in turn reiterates, a narrowing of distance between the state and civil society.
Including civil society in climate policy decision making and implementation is considered positive and inclusive, however, it is important to note that civil society is not always and everywhere inclusive and transformative.
Both at global and national levels, it is claimed that climate change interventions happen in an overall framework of participatory, inclusive environmental governance; in relation to hydropower development, we note that this is hardly the practice on the ground.
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