Computer program analyzes and monitors electrical power systems (POSIMO)

Requirements to monitor and/or simulate electric power distribution, power balance, and charge budget are discussed. Computer program to analyze power system and generate set of characteristic power system data is described. Application to status indicators to denote different exclusive conditions is presented

Disentanglement and decoherence in a pair of qutrits under dephasing noise

We relate disentanglement and decoherence rates in a pair of three-level atoms subjected to multi-local and collective pure dephasing noise acting in a preferred basis. The bipartite entanglement decay rate, as bounded from above by the negativity, is found to be greater than or equal to the dephasing-decoherence rates characterized by the decay of off-diagonal elements in the corresponding full density matrix describing the system or the reduced density matrix describing either qutrit, extending previous results for qubit pairs subject to such noise.Comment: 9 pages, submitted to J. Mod. Opt. 01/21/07, accepted 08/14/07 Version 2 corrections: 1) E and D operators in second-to-last paragraph of Sec. 2. 2) matrix elements (8,6) and (9,1) in Eq.

The Environmental Kuznets Curve from Multiple Perspectives

The analysis finds that in addition to U-shaped paths of environmental quality arising for growth in income per capita, growth in population can also produce socially efficient patterns that are U-shaped. Sufficient conditions for both types of paths are identified for a range of models and parameters, including symmetrical models with homothetic, constant-returns functions such as with CES functions. Similar results are also shown to arise in decentralized economies under either homogeneous or heterogeneous income levels.Environmental Kuznets Curve, Economic Growth, Environmental Quality

Reform options for pay-as-you-go public pension systems

Public pension schemes in many countries are predominantly of a pay-as-you-go (PAYG) type, particularly in advanced and transition economies. This paper reviews the types of stresses that PAYG systems can experience and discusses a range of policy options to preserve the financial stability of public PAYG systems. Section 1 introduces the basic policy levers of a stylized PAYG system. Section 2 discusses the key short- and long-run financial challenges faced by PAYG systems. Section 3 covers parametric adjustments in the basic PAYG policy levers as well as administrative reforms. Section 4 describes broader reform strategies for maintaining financial equilibrium in a PAYG system including the option of partial funding.Pensions&Retirement Systems,Environmental Economics&Policies,Economic Stabilization,Banks&Banking Reform,National Governance

The persistence of self-employment across borders: new evidence on legal immigrants to the United States

Using recently-available data from the New Immigrant Survey, we find that previous self-employment experience in an immigrant’s country of origin is an important determinant of their self-employment status in the U.S., increasing the probability of being self-employed by about 7 percent. Our results improve on the previous literature by measuring home-country self-employment directly rather than relying on proxy measures. We find little evidence to suggest that home-country self employment has a significant effect on U.S. wages in either paid employment or self employment

UHE neutrino searches using a Lunar target: First Results from the RESUN search

During the past decade there have been several attempts to detect cosmogenic ultra high energy (UHE) neutrinos by searching for radio Cerenkov bursts resulting from charged impact showers in terrestrial ice or the lunar regolith. So far these radio searches have yielded no detections, but the inferred flux upper limits have started to constrain physical models for UHE neutrino generation. For searches which use the Moon as a target, we summarize the physics of the interaction, properties of the resulting Cerenkov radio pulse, detection statistics, effective aperture scaling laws, and derivation of upper limits for isotropic and point source models. We report on initial results from the RESUN search, which uses the Expanded Very Large Array configured in multiple sub-arrays of four antennas at 1.45 GHz pointing along the lunar limb. We detected no pulses of lunar origin during 45 observing hours. This implies upper limits to the differential neutrino flux E^2 dN/dE < 0.003 EeV km^{-2} s^{-1} sr^{-1} and < 0.0003 EeV km$^{-2} s^{-1} at 90% confidence level for isotropic and sampled point sources respectively, in the neutrino energy range 10^{21.6} < E(eV) < 10^{22.6}. The isotropic flux limit is comparable to the lowest published upper limits for lunar searches. The full RESUN search, with an additional 200 hours observing time and an improved data acquisition scheme, will be be an order of magnitude more sensitive in the energy range 10^{21} < E(eV) < 10^{22} than previous lunar-target searches, and will test Z burst models of neutrino generation.Comment: 26 pages, 14 figure