49,883 research outputs found
With HMS \u3cem\u3ePrince of Wales\u3c/em\u3e and HMS \u3cem\u3eWarspite\u3c/em\u3e: The Adventures of a Canadian Radar Officer in the Royal Navy
Electronic payments in the U.S. economy : an overview
Business publications are filled these days with stories about the digital or electronic economy. One routinely reads about e-commerce, e-business, and e-banking. Terms such as e-mail and e-tickets have entered the common lexicon. Some analysts have gone so far as to proclaim that the U.S. economy is being fundamentally transformed and is entering a "new age" of unparalleled growth and opportunity.> While such a view is open to debate, clearly some major, potentially far-ranging, changes are under way. The most visible and most dramatic involve e-commerce. A growing amount of economic activity is taking place on the Internet, directly or indirectly impacting households and businesses throughout the economy. Less visible, but also significant, are changes involving "e-payments." Although the U.S. payments system continues to rely heavily on paper-based methods, cash and checks, for conducting transactions, electronic payments are steadily gaining a greater presence.> Weiner provides an overview of e-payments as they currently exist in the United States. He shows that the U.S. payments system is becoming more electronic, principally through traditional means. While new instruments are beginning to emerge, it is the traditional e-payment types--credit cards, debit cards, and ACH transactions--that are driving the U.S. payments system forward.Payment systems
Challenges to the natural rate framework
By most estimates, the U.S. unemployment rate is currently below its "natural rate." The implication is the economy is operating at an unsustainably high level of resource utilization. Capacity levels are being strained, tending to put upward pressure on wages and prices. In anticipation of these rising inflationary pressures, the Federal Reserve has firmed monetary policy several times over the past year.> A majority of mainstream economists appear comfortable with the natural rate framework, in part because it has tracked inflation successfully over the past 35 years. Despite its excellent record, however, the natural rate framework has not been without critics. In the past year, nonbelievers have advanced a number of arguments for why mounting inflationary pressures should not be a concern at this time. These arguments have focused on the heightened globalization of the marketplace, the weak bargaining position of the labor force, widespread productivity gains, and the absence to date of an unambiguous rise in inflation.> In this article, adapted from presentations made to the National Economists Club and the Congressional Budget Office in February 1995, Weiner considers the arguments against the natural rate framework. He offers some counterarguments and concludes that concerns about future inflationary pressures are well founded.Inflation (Finance) ; Unemployment
Social media analytics are evolving: from twitter-based crisis mapping to large-scale real-time situation assessment with trust and credibility analysis
Taking Heisenberg's Potentia Seriously
It is argued that quantum theory is best understood as requiring an
ontological duality of res extensa and res potentia, where the latter is
understood per Heisenberg's original proposal, and the former is roughly
equivalent to Descartes' 'extended substance.' However, this is not a dualism
of mutually exclusive substances in the classical Cartesian sense, and
therefore does not inherit the infamous 'mind-body' problem. Rather, res
potentia and res extensa are proposed as mutually implicative ontological
extants that serve to explain the key conceptual challenges of quantum theory;
in particular, nonlocality, entanglement, null measurements, and wave function
collapse. It is shown that a natural account of these quantum perplexities
emerges, along with a need to reassess our usual ontological commitments
involving the nature of space and time.Comment: Final version, to appear in International Journal of Quantum
Foundation
Reference image selection for difference imaging analysis
Difference image analysis (DIA) is an effective technique for obtaining
photometry in crowded fields, relative to a chosen reference image. As yet,
however, optimal reference image selection is an unsolved problem. We examine
how this selection depends on the combination of seeing, background and
detector pixel size. Our tests use a combination of simulated data and quality
indicators from DIA of well-sampled optical data and under-sampled
near-infrared data from the OGLE and VVV surveys, respectively. We search for a
figure-of-merit (FoM) which could be used to select reference images for each
survey. While we do not find a universally applicable FoM, survey-specific
measures indicate that the effect of spatial under-sampling may require a
change in strategy from the standard DIA approach, even though seeing remains
the primary criterion. We find that background is not an important criterion
for reference selection, at least for the dynamic range in the images we test.
For our analysis of VVV data in particular, we find that spatial under-sampling
is best handled by reversing the standard DIA procedure and convolving target
images to a better-sampled (poor seeing) reference image.Comment: 14 pages, 8 figures, 4 tables, accepted for publication in MNRA
Interchange fees in various countries : developments and determinants
Debit cards ; Credit cards
Radiological health risks to astronauts from space activities and medical procedures
Radiation protection standards for space activities differ substantially from those applied to terrestrial working situations. The levels of radiation and subsequent hazards to which space workers are exposed are quite unlike anything found on Earth. The new more highly refined system of risk management involves assessing the risk to each space worker from all sources of radiation (occupational and non-occupational) at the organ level. The risk coefficients were applied to previous space and medical exposures (diagnostic x ray and nuclear medicine procedures) in order to estimate the radiation-induced lifetime cancer incidence and mortality risk. At present, the risk from medical procedures when compared to space activities is 14 times higher for cancer incidence and 13 times higher for cancer mortality; however, this will change as the per capita dose during Space Station Freedom and interplanetary missions increases and more is known about the risks from exposure to high-LET radiation
Income inequality : a summary of the Bank's 1998 Symposium
Income inequality has become an increasingly important public policy issue in industrialized countries in recent years. Although macroeconomic conditions have been favorable in many of these countries, the distribution of income within and across countries has remained uneven. In fact, in several countries, income inequality has risen. As a result, policymakers have become concerned that large segments of the population are not reaping the benefits of economic growth.> To gain a better understanding of these issues, the Federal Reserve Bank of Kansas City sponsored a symposium titled "Income Inequality: Issues and Policy Options" held at Jackson Hole, Wyoming, August 27-29, 1998. The symposium brought together a distinguished group of public officials, academics, and private-sector representatives. The discussion was far-ranging and insightful. As moderator Alice Rivlin noted toward the end of the conference, while there was a divergence of opinion in several areas, there was a consensus that "poverty, deprivation, and lack of opportunity are things that ought to be of great concern to us."> Weiner and Monto summarize the papers and commentary presented at the symposium. The first section reviews the changes in income inequality patterns over the past two decades. The second explores the reasons for these changes. Monetary policy links and the economic impact of distributional change are taken up in the following two sections. The final section considers policy options and summarizes the remarks of an overview panel.Income ; Income distribution
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