18 resultados para Interest rates -- Australia -- Mathematical models.
Resumo:
Since the financial crash of 2008 monetary policy has been in a state of stasis – a condition in which things are not changing, moving, or progressing, but rather appear frozen. Interest rates have been frozen at low levels for a considerable period time. Inflation targets have consistently been missed, through phases of both overshooting and undershooting. At the same time, a variety of unconventional monetary policies involving asset purchases and liquidity provision have been pursued. Questions have been raised from a variety of sources, including various international organizations, covering distinct BIS and IMF positions about the continuing validity and sustainability of existing monetary policy frameworks, not least because inflation targeting has ceased to act as reliable guide for policy for over six years. Despite this central banks have been reluctant to debate moving to a new formal policy framework. This article argues that as an apex policy forum only the G20 leaders’ summits has the necessary political authority to call their central banks to account and initiate a wide ranging debate on the future of monetary policy. A case is made for convening a monetary policy working group to discuss a range of positions, including those of the BIS and IMF, and to make recommendations, because the G20 has been most effective in displaying international financial leadership, when leaders have convened and made use of specialist working groups.
Resumo:
Mathematical models are useful tools for simulation, evaluation, optimal operation and control of solar cells and proton exchange membrane fuel cells (PEMFCs). To identify the model parameters of these two type of cells efficiently, a biogeography-based optimization algorithm with mutation strategies (BBO-M) is proposed. The BBO-M uses the structure of biogeography-based optimization algorithm (BBO), and both the mutation motivated from the differential evolution (DE) algorithm and the chaos theory are incorporated into the BBO structure for improving the global searching capability of the algorithm. Numerical experiments have been conducted on ten benchmark functions with 50 dimensions, and the results show that BBO-M can produce solutions of high quality and has fast convergence rate. Then, the proposed BBO-M is applied to the model parameter estimation of the two type of cells. The experimental results clearly demonstrate the power of the proposed BBO-M in estimating model parameters of both solar and fuel cells.
Resumo:
Whole genome sequencing (WGS) technology holds great promise as a tool for the forensic epidemiology of bacterial pathogens. It is likely to be particularly useful for studying the transmission dynamics of an observed epidemic involving a largely unsampled 'reservoir' host, as for bovine tuberculosis (bTB) in British and Irish cattle and badgers. BTB is caused by Mycobacterium bovis, a member of the M. tuberculosis complex that also includes the aetiological agent for human TB. In this study, we identified a spatio-temporally linked group of 26 cattle and 4 badgers infected with the same Variable Number Tandem Repeat (VNTR) type of M. bovis. Single-nucleotide polymorphisms (SNPs) between sequences identified differences that were consistent with bacterial lineages being persistent on or near farms for several years, despite multiple clear whole herd tests in the interim. Comparing WGS data to mathematical models showed good correlations between genetic divergence and spatial distance, but poor correspondence to the network of cattle movements or within-herd contacts. Badger isolates showed between zero and four SNP differences from the nearest cattle isolate, providing evidence for recent transmissions between the two hosts. This is the first direct genetic evidence of M. bovis persistence on farms over multiple outbreaks with a continued, ongoing interaction with local badgers. However, despite unprecedented resolution, directionality of transmission cannot be inferred at this stage. Despite the often notoriously long timescales between time of infection and time of sampling for TB, our results suggest that WGS data alone can provide insights into TB epidemiology even where detailed contact data are not available, and that more extensive sampling and analysis will allow for quantification of the extent and direction of transmission between cattle and badgers. © 2012 Biek et al.