The Monopole Antenna With a Small Number of Radials

This paper reports a study of an antenna system consisting of a vertical monopole and a small number of insulated horizontal radials lying lightly on the ground. The monopole antenna has long been popular for medium frequency broadcasting because of its inherent simplicity and economy. Although quarter-wavelength resonant structures were used in the early days, it was shown by Ballantine (1924) that for a given power, the strongest field strength at the radio horizon was produced by an antenna about 0.6 wavelength long. This ignored the sky wave and was based on the assumption of a perfectly conducting (and reflecting) earth. With the same assumption, Brown (1935) computed the earth currents produced by a vertical monopole having a sinusoidal current distribution. He also estimated the ground power loss for a ground of infinite conductivity, assuming it had the same tangential magnetic field on its surface as when perfectly conducting. This is a reasonably good approximation under certain conditions and has been used by many writers following Brown (e.g. Wait &Surtees (1954), Monteath (1958), etc.)

Backscatter of Electromagnetic Waves from a Rough Layer

Backscatter of electromagnetic waves from rough surfac

Backscatter of Ultrasonic Waves from a Rough Layer

Kirchhoff approximation used to calculate backscatter of ultrasonic waves from rough laye

Current hiring practices in the restaurant industry: An example of California restaurants

Employee hiring is a crucial function in any organization. Adherence to hiring practices that are fair, ethical, and non-discriminatory are vital to both organizations and job applicants. This three-phase study examined hiring practices in the restaurant industry with a focus on the interview step from the perspectives of human resource (HR) managers, unit-level managers, and job applicants. Significant differences were found between the Council of Hotel and Restaurant Trainers HR managers\u27 attitudes toward ethical hiring and ethnicity, while significant differences were observed between organizational size and perceptions of ethical hiring within organizations. Unit-level restaurant managers from California restaurants used a variety of methods when recruiting and hiring employees and believed they had adequate policies and procedures in place to ensure ethical hiring. While, verbal and non-verbal cues of the interviewer were perceived as indicators of ethical or unethical hiring practices by job applicants who interviewed for employment in California restaurants. Given the diversity in today\u27s labor market, findings from this study offer a promising view that conveys potential for impacting operations and thus affecting the hiring of millions of foodservice workers

Variation of Electrostatic Coupling and Investigation of Current Percolation Paths in Nanocrystalline Silicon Cross Transistors

Nanocrystalline silicon thin films are promising materials for the development of advanced Large Scale Integration compatible quantum-dot and single-electron charging devices. The films consist of nanometer-scale grains of crystalline silicon, separated by amorphous silicon or silicon dioxide grain boundaries up to a few nanometer thick. These films have been used to fabricate single-electron transistor and memory devices, where the grains form single-electron charging islands isolated by tunnel barriers formed by the grain boundaries. The grain boundary tunnel barrier isolating the grains is also of great importance, as this determines the extent of the electrostatic and tunnel coupling between different grains. These effects can lead to the nanocrystalline silicon thin film behaving as a system of coupled quantum dots.& more..

The KSU Acoustic Simulator for Radar Studies

Equipment and instrumentation for acoustic simulation of electromagnetic wave propagation and radar systems design studie