Public choices between lifesaving programs : how important are lives saved?

In developing and industrial countries alike, there is concern that health and safety policy may respond to irrational fears - to the"disaster of the month"- rather than address more fundamental problems. In the United States, for example, some policymakers say the public worries about trivial risks while ignoring larger ones and that funding priorities reflect this view. Many public health programs with a low cost per life saved are underfunded, for example, while many environmental regulations with a high cost per life saved are issued each year. Does the existing allocation of resources reflect people's preoccupation with the qualitative aspects of risks, to the exclusion of quantitative factors (lives saved)? Or can observed differences in the cost per life saved of environmental and public health programs be explained by the way the two sets of programs are funded? The authors examine the preferences of U.S. citizens for health and safety programs. They confronted a random sample of 1,000 U.S. adults with choices between environmental health and public health programs, to see which they would choose. The authors then examined what factors (qualitative and quantitative) seem to influence these choices. Respondents were asked about pairs of programs, among them: smoking education or industrial pollution control programs, industrial pollution control or pneumonia vaccine programs, radon eradication or a program to ban smoking in the workplace, and radon eradication or programs to ban pesticides. The survey results, they feel, have implications beyond the United States. They find that, while qualitative aspects of the life-saving programs are statistically significant in explaining people's choices among them, lives saved matter, too. Indeed, for the median respondent in the survey, the rate of substitution between most qualitative risk characteristics and lives saved is inelastic. But for a sizable minority of respondents, choice among programs appears to be insensitive to lives saved. The interesting question for public policy is what role the latter group plays in the regulatory process.Health Monitoring&Evaluation,Public Health Promotion,Insurance&Risk Mitigation,Insurance Law,Water Conservation,Health Monitoring&Evaluation,Insurance&Risk Mitigation,Insurance Law,Water Conservation,Environmental Economics&Policies

Global logistics indicators, supply chain metrics, and bilateral trade patterns

Past research into the determinants of international trade highlighted the importance of the basic spatial gravity model augmented by additional variables representing sources of friction. Studies modeled many sources of friction using various proxies, including indices based on expert judgment in some cases. This paper focuses on logistics friction and draws on a data set recently compiled by the World Bank with specific quantitative metrics of logistics performance interms of time, cost, and variability in time. It finds that the new variables that relate directly to logistics performance have a statistically significant relationship with the level of bilateral trade. It also finds that a single logistics index can capture virtually all of the explanatory power of multiple logistics indicators. The findings should spur public and private agencies that have direct or indirect power over logistics performance to focus attention on reducing sources of friction so as to improve their country's ability to compete in today's global economy. Moreover, since the logistics metrics are directly related to operational performance, countries can use these metrics to target actions to improve logistics and monitor their progress.Common Carriers Industry,Transport and Trade Logistics,Economic Theory&Research,Free Trade,Trade Policy

The scaling of the decoherence factor of a qubit coupled to a spin chain driven across quantum critical points

We study the scaling of the decoherence factor of a qubit (spin-1/2) using the central spin model in which the central spin (qubit) is globally coupled to a transverse XY spin chain. The aim here is to study the non-equilibrium generation of decoherence when the spin chain is driven across (along) quantum critical points (lines) and derive the scaling of the decoherence factor in terms of the driving rate and some of the exponents associated with the quantum critical points. Our studies show that the scaling of logarithm of decoherence factor is identical to that of the defect density in the final state of the spin chain following a quench across isolated quantum critical points for both linear and non-linear variations of a parameter even if the defect density may not satisfy the standard Kibble-Zurek scaling. However, one finds an interesting deviation when the spin chain is driven along a critical line. Our analytical predictions are in complete agreement with numerical results. Our study, though limited to integrable two-level systems, points to the existence of a universality in the scaling of the decoherence factor which is not necessarily identical to the scaling of the defect density.Comment: 5 pages, 2 figures, Final and accepted versio

The effect of a light radion on the triviality bound on higgs mass

In this paper we study how the triviality bound on higgs mass in the context of the SM is modified by a light stabilized radion of the Goldberger-Wise variety. Our approach is inherently perturbative. Including the radion contribution to \bt(\l) and \bt(g_t) to one loop we evolve the higgs self coupling \l from the cut off \L(=\vphi) down to the EW scale $\mu_0 = v$. The triviality bound is obtained by requiring that \l(\L) = \sqrt{4 \pi} which is the perturbative limit. We also study the effect of small changes in the UVBC on the triviality bound both in the presence and absence of a light radion.Comment: 9 pages, latex, 2 eps figure

Impact of Daily Arctic Sea Ice Variability in CAM3.0 during Fall and Winter

Climate projections suggest that an ice-free summer Arctic Ocean is possible within several decades and with this comes the prospect of increased ship traffic and safety concerns. The daily sea ice concentration tendency in five Coupled Model Intercomparison Project phase 5 (CMIP5) simulations is compared with observations to reveal that many models underestimate this quantity that describes high-frequency ice movements, particularly in the marginal ice zone. To investigate whether high-frequency ice variability impacts the atmosphere, the Community Atmosphere Model, version 3.0 (CAM3.0), is forced by sea ice with and without daily fluctuations. Two 100-member ensemble experiments with daily varying (DAILY) and smoothly varying (SMTH) sea ice are conducted, along with a climatological control, for an anoma- lously low ice period (August 2006–November 2007). Results are presented for three periods: September 2006, October 2006, and December–February (DJF) 2006/07. The atmospheric response differs between DAILY and SMTH. In September, sea ice differences lead to an anomalous high and weaker storm activity over northern Europe. During October, the ice expands equatorward faster in DAILY than SMTH in the Siberian seas and leads to a local response of near-surface cooling. In DJF, there is a 1.5-hPa positive sea level pressure anomaly over North America, leading to anomalous northerly flow and anomalously cool continental U.S. temperatures. While the atmospheric responses are modest, the differences arising from high temporal frequency ice variability cannot be ignored. Increasing the accuracy of coupled model sea ice variations on short time scales is needed to improve short-term coupled model forecasts

In-medium dependence and Coulomb effects of the pion production in heavy ion collisions

The properties of the high energy pions observed in heavy ion collisions, in particular in the system Au on Au at 1 GeV/nucleon are investigated. The reaction dynamics is described within the Quantum Molecular Dynamics (QMD) approach. It is shown that high energy pions freeze out early and originate from the hot, compressed matter. $N^*$--resonances are found to give an important contribution toward the high energy tail of the pion. Further the role of in-medium effects in the description of charged pion yields and spectra is investigated using a microscopic potential derived from the Brueckner G-matrix which is obtained with the Reid soft-core potential. It is seen that the high energy part of the spectra is relatively more suppressed due to in-medium effects as compared to the low energy part. A comparision to experiments further demonstrates that the present calculations describe reasonably well the neutral (TAPS) and charged (FOPI) pion spectra. The observed energy dependence of the $\pi^-/\pi^+$ ratio, i.e. deviations from the isobar model prediction, is due to Coulomb effects and again indicate that high energy pions probe the hot and dense phase of the reaction. These findings are confirmed independently by a simple phase space analysis.Comment: 28 pages Latex, prepared with elsevier-style, 13 PS-figure

Quenching Dynamics of a quantum XY spin-1/2 chain in presence of a transverse field

We study the quantum dynamics of a one-dimensional spin-1/2 anisotropic XY model in a transverse field when the transverse field or the anisotropic interaction is quenched at a slow but uniform rate. The two quenching schemes are called transverse and anisotropic quenching respectively. Our emphasis in this paper is on the anisotropic quenching scheme and we compare the results with those of the other scheme. In the process of anisotropic quenching, the system crosses all the quantum critical lines of the phase diagram where the relaxation time diverges. The evolution is non-adiabatic in the time interval when the parameters are close to their critical values, and is adiabatic otherwise. The density of defects produced due to non-adiabatic transitions is calculated by mapping the many-particle system to an equivalent Landau-Zener problem and is generally found to vary as $1/\sqrt{\tau}$, where $\tau$ is the characteristic time scale of quenching, a scenario that supports the Kibble-Zurek mechanism. Interestingly, in the case of anisotropic quenching, there exists an additional non-adiabatic transition, in comparison to the transverse quenching case, with the corresponding probability peaking at an incommensurate value of the wave vector. In the special case in which the system passes through a multi-critical point, the defect density is found to vary as $1/\tau^{1/6}$. The von Neumann entropy of the final state is shown to maximize at a quenching rate around which the ordering of the final state changes from antiferromagnetic to ferromagnetic.Comment: 8 pages, 6 figure

Multi-Machine Stability Using Dynamic Inversion Technique

Stability studies of multi machine system are a major concern to power system engineers due to the increasing complexity involved. This paper deals with the application of a nonlinear technique called Dynamic Inversion, to TCSC for the improvement of stability of multi-machine system. The transient stability studies for various cases: without any controller, with 75% line compensation and with Dynamic Inversion technique, are compared. The critical clearing time as well as the maximum loading ability is also discussed. The result for the nonlinear controller is found to be better than all the other cases