Study of Apollo water impact. Volume 2 - Dynamic response of shells of revolution during vertical impact into water - No interaction Final report

Mathematical model for predicting dynamic response of thin elastic shells of revolution during water impac

Monte--Carlo Thermodynamic Bethe Ansatz

We introduce a Monte--Carlo simulation approach to thermodynamic Bethe ansatz (TBA). We exemplify the method on one particle integrable models, which include a free boson and a free fermions systems along with the scaling Lee--Yang model (SLYM). It is confirmed that the central charges and energies are correct to a very good precision, typically 0.1% or so. The advantage of the method is that it enables the calculation of all the dimensions and even the particular partition function.Comment: 22 pages. Added a footnote and realizations for the minimal models. Fortran program, mont-s.f90, available from the source lin

Classification of Quantum Hall Universality Classes by $\ W_{1+\infty}\ $ symmetry

We show how two-dimensional incompressible quantum fluids and their excitations can be viewed as $\ W_{1+\infty}\$ edge conformal field theories, thereby providing an algebraic characterization of incompressibility. The Kac-Radul representation theory of the $\ W_{1+\infty}\$ algebra leads then to a purely algebraic complete classification of hierarchical quantum Hall states, which encompasses all measured fractions. Spin-polarized electrons in single-layer devices can only have Abelian anyon excitations.Comment: 11 pages, RevTeX 3.0, MPI-Ph/93-75 DFTT 65/9

Solar cell radiation response near the interface of different atomic number materials

The response of cobalt 60 irradiated N/P silicon solar cells was measured as a function of the atomic number of the medium adjacent to the cell and the direction of the gamma ray beam. The interpositioning of various thicknesses of aluminum between the adjacent material and the cell had the effect of moving the cell to various locations in an approximate monatomic numbered medium. Using this technique the solar cell response was determined at various distances from the interface for gold and beryllium. The results were compared with predictions based upon ionization chamber measurements of dose perturbations in aluminum and found to agree within five percent. Ionization chamber data was then used to estimate the influence of various base contact materials

Quantum Bubble Dynamics in 2+1 Dimensional Gravity I: Geometrodynamic Approach

The Dirac quantization of a 2+1 dimensional bubble is performed. The bubble consists of a string forming a boundary between two regions of space-time with distinct geometries. The ADM constraints are solved and the coupling to the string is introduced through the boundary conditions. The wave functional is obtained and the quantum uncertainty in the radius of the ring is calculated; this uncertainty becomes large at the Planck scale.Comment: 14 pages, Latex (\cite typos corrected

A Supply-Chain Approach to Talent Management

Talent management is the process through which employers anticipate and meet their needs for human capital. It is about getting the right people with the right skills into the right jobs at the right time. It is a lot to get right, and few organizations do. The difficulty in getting it right is a problem for firms insofar as talent-management decisions shape firm competencies and success. It is a problem for workers, because these decisions impact their careers. And it is ultimately a problem for society, because these decisions, in aggregate, ultimately affect economic growth and social stability

A note on the topological order of noncommutative Hall fluids

We evaluate the ground state degeneracy of noncommutative Chern-Simons models on the two-torus, a quantity that is interpreted as the "topological order" of associated phases of Hall fluids. We define the noncommutative theory via T-duality from an ordinary Chern-Simons model with non-abelian 't Hooft magnetic fluxes. Motivated by this T-duality, we propose a discrete family of noncommutative, non-abelian fluid models, arising as a natural generalization of the standard noncommutative Chern-Simons effective models. We compute the topological order for these universality classes, and comment on their possible microscopic interpretation.Comment: 14 page

Chiral persistent currents and magnetic susceptibilities in the parafermion quantum Hall states in the second Landau level with Aharonov-Bohm flux

Using the effective conformal field theory for the quantum Hall edge states we propose a compact and convenient scheme for the computation of the periods, amplitudes and temperature behavior of the chiral persistent currents and the magnetic susceptibilities in the mesoscopic disk version of the Z_k parafermion quantum Hall states in the second Landau level. Our numerical calculations show that the persistent currents are periodic in the Aharonov-Bohm flux with period exactly one flux quantum and have a diamagnetic nature. In the high-temperature regime their amplitudes decay exponentially with increasing the temperature and the corresponding exponents are universal characteristics of non-Fermi liquids. Our theoretical results for these exponents are in perfect agreement with those extracted from the numerical data and demonstrate that there is in general a non-trivial contribution coming from the neutral sector. We emphasize the crucial role of the non-holomorphic factors, first proposed by Cappelli and Zemba in the context of the conformal field theory partition functions for the quantum Hall states, which ensure the invariance of the annulus partition function under the Laughlin spectral flow.Comment: 14 pages, RevTeX4, 7 figures (eps

Missing girls in Liberal Italy, 1861–1921

By relying on the number of (surviving) boys per hundred girls observed in the population censuses as a cumulative measure of differential mortality during birth, infancy, and childhood, this paper shows that average Italian child sex ratios (aged 0–4) were abnormally high between 1861 and 1921. Our estimations indicate that unexplained excess female mortality resulted in around 2–3 per cent of ‘missing girls’ during this period. Likewise, by constructing a new dataset on child sex ratios at the provincial level during the same period, this article shows that child sex ratios tended to be higher in Southern Italy, a geographical cleavage that became stronger as time went by. Crucially, the results reported here cannot be explained by registration issues because (1) the analysis holds if we focus on the sex ratios of older children (aged 5–9) and (2) these patterns are also clearly visible using death registers. Unexplained excess female mortality early in life disappeared from the 1920s onwards, thus suggesting that either discriminatory practices gradually vanished and/or that they no longer translated into higher mortality rates due to enhanced living standards