The Iowa Pitch Range Audiometer

The ideal apparatus for measuring the acuity of the ear should enable one to determine the faintest audible sound at each and every pitch within the tonal range. It should be easily and quickly operated and should be permanently standardized. The Pitch Range Audiometer is an approach to this ideal

Ultra-Short Optical Pulse Generation with Single-Layer Graphene

Pulses as short as 260 fs have been generated in a diode-pumped low-gain Er:Yb:glass laser by exploiting the nonlinear optical response of single-layer graphene. The application of this novel material to solid-state bulk lasers opens up a way to compact and robust lasers with ultrahigh repetition rates.Comment: 6 pages, 3 figures, to appear in Journal of Nonlinear Optical Physics & Material

Novel Modifications of Parallel Jacobi Algorithms

We describe two main classes of one-sided trigonometric and hyperbolic Jacobi-type algorithms for computing eigenvalues and eigenvectors of Hermitian matrices. These types of algorithms exhibit significant advantages over many other eigenvalue algorithms. If the matrices permit, both types of algorithms compute the eigenvalues and eigenvectors with high relative accuracy. We present novel parallelization techniques for both trigonometric and hyperbolic classes of algorithms, as well as some new ideas on how pivoting in each cycle of the algorithm can improve the speed of the parallel one-sided algorithms. These parallelization approaches are applicable to both distributed-memory and shared-memory machines. The numerical testing performed indicates that the hyperbolic algorithms may be superior to the trigonometric ones, although, in theory, the latter seem more natural.Comment: Accepted for publication in Numerical Algorithm

The Influence of Intensity Ratio on Binaural Sound Localization

It has been recognized that the intensity ratio at the ears is a factor in the localization of sound, but it appears that its influence has been greatly over-estimated. In the summer of 1916 G. W. Stewart and O. Hovda did considerable qualitative work on this. Our present research is a continuation of their work with practically the same apparatus

Self Similar Solutions of the Evolution Equation of a Scalar Field in an Expanding Geometry

We consider the functional Schrodinger equation for a self interacting scalar field in an expanding geometry. By performing a time dependent scale transformation on the argument of the field we derive a functional Schrodinger equation whose hamiltonian is time independent but involves a time-odd term associated to a constraint on the expansion current. We study the mean field approximation to this equation and generalize in this case, for interacting fields, the solutions worked out by Bunch and Davies for free fields.Comment: 8 pages, Latex, IPNO/TH 94-3

Assessing thePrior Intercultural Experiences,Motivating Factorsand Deterrentsinfluencing4-H Members’ Intention to Participate an International Experience Program

International experience programs (IEPs), such as International 4-H Youth Exchange (IFYE) and other programs employed by U.S Cooperative Extension Programs and international partners, can forge students’ development of a global perspective. The purpose of this study was to determine 4-H members’ prior intercultural experience, perceived motivating factors to participation in an IEP, perceived deterrents to participation in an IEP, and 4-H members’ intentions to participate in an IEP; and to explain 4-H members’ intention to participate in an IEP. Results of this study suggest that 4-H members’ intention to participate in an IEP is predicted by prior intercultural experiences. The effect of prior intercultural experiences is mediated by motivating factors, that is as motivating factors increase, intent increases while reducing the effect of prior intercultural experiences. A recommendation for practitioners to use to bridge the gap between 4-H members and other cultures is to provide varied intercultural experiences in or near the youths’ own communit

Protostellar disks and the primitive solar nebula

The objective is to obtain quantitative information on the turbulent transport of mass, angular momentum, and energy under the conditions that characterize the solar nebula, by direct numerical calculations. These calculations were made possible by research conducted on supercomputers (Cray XMP and Cray 2) by the Ames Computational Fluid Dynamics Branch. Techniques were developed that permitted the accurate representation of turbulent flows over the full range of important eddy sizes. So far, these techniques were applied (and verified) primarily in mundane laboratory situations, but they have a strong potential for astrophysical applications. A sequence of numerical experiments were conducted to evaluate the Reynold's stress tensor, turbulent heat transfer rate, turbulent dissipation rate, and turbulent kinetic energy spectrum, as functions of position, for conditions relevant to the solar nebula. Emphasis is placed on the variation of these properties with appropriate nondimensional quantities, so that relations can be derived that will be useful for disk modeling under a variety of hypotheses and initial conditions

Examining the motivations and barriers influencing the decisions of Louisiana state university college of agriculture freshmen to participate in international experiences

© 2015, Assoc. Int. Agricultural and Extension Education. All rights reserved. Over the past decade, universities in the United States (U.S) have increased time and financial investments put toward internationalizing their curricula, particularly in efforts to increase students’ participation in international experiences (IEs). Despite efforts, only 10% of U.S students participated in an IE in the 2011/2012 academic year, of which only 1.3% included students in agriculturally-related majors. The purpose of the study was to examine the motivations and barriers influencing the decisions of College of Agriculture (CoA) freshmen to participate in an international experience (IE). The majority of freshmen were interested in an IE, and they perceived their participation would be at least somewhat important to their education and future career. Overall life experience gained and looks good on a résumé were perceived as the most important motivations. Cost and lack of information were the greatest barriers perceived by freshman students. Freshmen who perceived the most motivations also had greater interest in an IE and viewed an IE as very important, while freshmen who perceived the fewest motivations were those who did not perceive an IE as important. It can be recommended that students who have participated previously in an IE deliver presentations during first year experience courses. These presentations should highlight global components of the curriculum using practical, job-oriented instructional methods that focus on the overall life experiences, career benefits, and résumé strength. To eliminate cost barriers and increase student participation in IEs, CoA administrators and faculty members should work with freshmen to help them locate scholarship opportunities early on in their college career