Atmospheric effects on CO2 laser propagation

An investigation was made of the losses encountered in the propagation of CO2 laser radiation through the atmosphere, particularly as it applies to the NASA/Marshall Space Flight Center Pulsed Laser Doppler System. As such it addresses three major areas associated with signal loss: molecular absorption, refractive index changes in a turbulent environment, and aerosol absorption and scattering. In particular, the molecular absorption coefficients of carbon dioxide, water vapor, and nitrous oxide are calculated for various laser lines in the region of 10.6 mu m as a function of various pressures and temperatures. The current status in the physics of low-energy laser propagation through a turbulent atmosphere is presented together with the analysis and evaluation of the associated heterodyne signal power loss. Finally, aerosol backscatter and extinction coefficients are calculated for various aerosol distributions and the results incorporated into the signal-to-noise ratio equation for the Marshall Space Flight Center system

A combinatorial identity for studying Sato-Tate type problems

We derive a combinatorial identity which is useful in studying the distribution of Fourier coefficients of L-functions by allowing us to pass from knowledge of moments of the coefficients to the distribution of the coefficients.Comment: This paper contains the proof of a combinatorial identity used to study effective equidistribution laws for the Fourier coefficients of elliptic curve L-functions investigated by the first two authors in http://arxiv.org/abs/1004.275

Ohio\u27s Post-Conviction Appeal Remedy

Ohio has recently adopted legislation intended to provide a prisoner with a means of testing, in the court which originally imposed sentence, the constitutional validity of his sentence. This legislation is intended to provide a remedy which will supplement the writ of habeas corpus. Jurisdiction in habeas corpus proceedings lies in the court of the county in which the prisoner is confined. In recent years the courts located in counties containing state correctional institutions have been deluged with habeas corpus petitions

In-Situ Nuclear Magnetic Resonance Investigation of Strain, Temperature, and Strain-Rate Variations of Deformation-Induced Vacancy Concentration in Aluminum

Critical strain to serrated flow in solid solution alloys exhibiting dynamic strain aging (DSA) or Portevin–LeChatelier effect is due to the strain-induced vacancy production. Nuclear magnetic resonance (NMR) techniques can be used to monitor in situ the dynamical behavior of point and line defects in materials during deformation, and these techniques are nondestructive and noninvasive. The new CUT-sequence pulse method allowed an accurate evaluation of the strain-enhanced vacancy diffusion and, thus, the excess vacancy concentration during deformation as a function of strain, strain rate, and temperature. Due to skin effect problems in metals at high frequencies, thin foils of Al were used and experimental results correlated with models based on vacancy production through mechanical work (vs thermal jogs), while in situ annealing of excess vacancies is noted at high temperatures. These correlations made it feasible to obtain explicit dependencies of the strain-induced vacancy concentration on test variables such as the strain, strain rate, and temperature. These studies clearly reveal the power and utility of these NMR techniques in the determination of deformation-induced vacancies in situ in a noninvasive fashion.

Corruptive Tendencies, Conscientiousness, and Collectivism

This research investigated the relation between conscientiousness, collectivism, and corrupt tendency–which is represented by moral emotions (shame and guilt proneness). The study was conducted on 117 students (76 male, 41 female; M = 18.93 years old; SD = 1.67 years old) in Jakarta. The result shows that collectivism has positive predictive correlation with the tendency of not doing corruption and that conscientiousness is not able to predict corrupt tendencies. Collectivism of which every group member has as a strong moral identity is suggested to be the ideal ecological situation which need to be built to prevent corruption in Indonesia

Representations of integers by certain positive definite binary quadratic forms

We prove part of a conjecture of Borwein and Choi concerning an estimate on the square of the number of solutions to n=x^2+Ny^2 for a squarefree integer N.Comment: 8 pages, submitte

Nitrogen isotopes in chondrules: signatures of precursors and formation processes

Nitrogen isotope abundance of 68 individual chondrules separated from six ordinary, two carbonaceous and two enstatite chondrites has been analysed. N composition of chondrules from ordinary and carbonaceous chondrites generally shows large variation and differs from that of their host. This large range of N composition suggests the presence of different N components in their precursors. Chondrules from the enstatite chondrites on the other hand show N isotopic composition similar to that of their host, suggesting precursors with similar N components for both chondrules and their host meteorites. Nitrogen isotopic systematics therefore distinguishes chondrules in enstatite chondrites from those in ordinary and carbonaceous chondrites. Chondrules in ordinary and carbonaceous chondrites require precursors that are different from those of their parent meteorites and formation in nebular environment, whereas chondrules in enstatite chondrites are formed from the same precursors as those of their host chondrites and presumably in the same region

A note on the culture of Chanos chanos (Forskal) at Brackishwater Fish Farm, Kaninada

The culture of Chanos chanos to marketable size within a three months period, is described. Procedures involved include phased manuring coupled with proper water management to keep up enhanced primary productivity. Results show that, under monoculture, with low-input technology it is possible to produce 3,000 kg fish per hectare per year

On modular signs

We consider some questions related to the signs of Hecke eigenvalues or Fourier coefficients of classical modular forms. One problem is to determine to what extent those signs, for suitable sets of primes, determine uniquely the modular form, and we give both individual and statistical results. The second problem, which has been considered by a number of authors, is to determine the size, in terms of the conductor and weight, of the first sign-change of Hecke eigenvalues. Here we improve significantly the recent estimate of Iwaniec, Kohnen and Sengupta.Comment: 23 pages, 1 figure; new version with new coauthor and strong improvements of two of the two main results