Prospects and problems in designing image oriented information systems

There are slowly maturing and growing about us today a number of techniques which are likely to have a very significant effect upon the implementation of information systems in the near future. One of these techniques is pictorial data handling and interpretation, which is a subclass of the general area called pattern recognition. Pictorial data processing first became volumetrically significant in the case of photographic output of synchrotron bubble chambers which now deliver several million photographs per year. More recently, a surge of interest has developed in automatic interpretation of biological, medical, and weather satellite pictorial data. The automatic scanning of microscopic slides for the purpose of identifying certain morphological characters is an example of a rather complex task in the area of biological/medical laboratory automation. Some new viewpoints have begun to emerge from the experience of grappling with large volume pictorial data handling problems.published or submitted for publicatio

The Reform and Design of Commodity Taxes in the Presence of Tax Evasion with Illustrative Evidence from India

The literature on tax evasion and its implication for optimal tax theory has concentrated on income tax evasion. The issue of commodity tax evasion has received relatively little attention even though it is important in many cases, especially in developing countries. This paper proposes a theory of marginal reform of indirect taxes that recognises the presence of commodity tax evasion. Illustrative evidence from Indian data confirm the sensitivity of the Pareto improving direction of marginal tax changes to alternative a priori assumptions on commodity tax evasion. The theory of marginal reform of commodity taxes is, then, extended to propose a theory of marginal reform of audits and penalties, and several propositions are derived. The underlying theory of tax design is also extended to include income tax design and income tax evasion, and a framework is proposed to allow the simultaneous analyses of both forms of tax evasion, and study of their impact on the "optimal mix" of direct and indirect taxes.

Finite Temperature and Density Effects in Planar Q.E.D

The behavior of finite temperature planar electrodynamics is investigated. We calculate the static as well as dynamic characteristic functions using real time formalism. The temperature and density dependence of dielectric and permeability functions, plasmon frequencies and their relation to the screening length is determined. The radiative correction to the fermion mass is also calculated. We also calculate the temperature dependence of the electron (anyon) magnetic moment. Our results for the gyromagnetic ratio go smoothly to the known result at zero temperature, $g=2$, in accordance with the general expectation.Comment: 24 pages, LaTe

Bulk and Edge excitations in a ν=1\nu =1 quantum Hall ferromagnet

In this article, we shall focus on the collective dynamics of the fermions in a $\nu = 1$ quantum Hall droplet. Specifically, we propose to look at the quantum Hall ferromagnet. In this system, the electron spins are ordered in the ground state due to the exchange part of the Coulomb interaction and the Pauli exclusion principle. The low energy excitations are ferromagnetic magnons. To provide a means for describing these magnons, we shall discuss a method of introducing collective coordinates in the Hilbert space of many-fermion systems. These collective coordinates are bosonic in nature. They map a part of the fermionic Hilbert space into a bosonic Hilbert space. Using this technique, we shall interpret the magnons as bosonic collective ex citations in the Hilbert space of the many-electron Hall system. By considering a Hall droplet of finite extent, we shall also obtain the effective Lagrangian governing the spin collective excitations at the edge of the sample.Comment: Plain TeX 18 Pages Proceedings for the Y2K conference on strongly c orrelated fermionic systems, Calcutta, Indi

Comment on "A note on the construction of the Ermakov-Lewis invariant"

We show that the basic results on the paper referred in the title [J. Phys. A: Math. Gen. v. 35 (2002) 5333-5345], concerning the derivation of the Ermakov invariant from Noether symmetry methods, are not new

Maturation and spawning of marine finfish

Fish utilized for spawning experiments were taken near Port Aransas, Tex., from estuarine and gulf populations of each species. Red drum, Sciaenops ocellata, were taken by hook-and-line and beach seine. Spotted seatrout, Cynoscion nebulosus, and red snapper, Lutjanus campechanus, were collected by hook-and-line. Southern flounder, Paralichthys lethostigma, were taken by hook-and-line and trammel net. Red drum and southern flounder were taken during their fall spawning period and spotted seatrout in the early spring season. Immature red snappers taken in early fall were placed in the spawning tank. The snapper tank was covered with nylon netting to prevent fish from jumping out of the tank. Red drum (750 mm TL), spotted trout (356 mm TL), and southern flounder (males 254 mm TL, females 305 mm TL) were kept as brood fish. Fish were transferred to the laboratory in fiber glass tanks (300-1,900 1) and placed into 1,000-30,000 l fiber glass spawning tanks. Fish were handled carefully to avoid surface abrasions which could result in infections. External parasites were removed with a 25-50 ppm bath of malachite green and Formalin. After this treatment the fish were placed in spawning tanks. Details of the seawater holding facilities are described by Arnold et al. (1976). Photoperiod and temperature data were gathered from U.S. Coast Guard and U.S. Weather Service records for Port Aransas, Tex. By comparing larval collections or adult spawning records of redfish (Simons and Breuer 1962), southern flounder (Stokes 1975), spotted trout (Miles 1950), and red snapper (Mosely 1966), the photoperiods and temperatures for the natural spawning seasons were determined. The laboratory photoperiod and temperature regimes for induced spawning of these four species were based on these meteorological and hydrological records.Marine Scienc