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Khirbat al-Mudaybi‘ is the site of an ancient fort on the eastern desert fringe of the Karak plateau in Jordan – an area known as Moab in biblical times. Little was known about the site until the Karak Resources Project between 1997 and 2014 excavated it. The most intriguing find at the site was a massive four-chambered gate decorated with ornate volute column capitals. Ceramic, architectural, and radiocarbon analysis indicate that the fort dates to the late Iron Age, very likely to the seventh century BCE. Who built it, why it was built and why such ornamental architecture was employed, and why it was abandoned remain questions to be answered. This article speculates that the fort was built by a Moabite ruler who, as a client-ruler of the powerful Neo-Assyrian Empire, was required to pay tribute to his overlords. This tribute came from levies on caravan traffic that passed by the site on the desert highway that connected Arabia with Damascus in the north. The impressive architecture was a symbol of royal authority. The fort was abandoned during the Neo-Babylonian period when the caravan route shifted and no longer passed the site.

Man-carried antennas usually identify the radio operator in a squad. The antennas are often whips that are narrowband and tailored to a particular radio. The Joint Tactical Radio with a frequency range from 2 MHz to 2 GHz presents new requirements. Incorporating the antenna into the uniform will hinder identification of the radio operator. A prototype of an antenna in the form of a Vest is part of the Combat Wear Integrated (COMWIN) Antenna System. The COMWIN vest antenna was fabricated and tested at the SPAWAR Systems Center. The design was proposed and analyzed theoretically by researchers at the Naval Postgraduate School. Impedance measurements showed close agreement with the theoretical predictions. The calculations had predicted a resonance at 95 MHz and a relatively constant impedance for higher frequencies. When a person wore the vest, the frequency of the resonance decreased to 65 MHz and the maximum impedance decreased by a factor of 4. When a transformer was inserted into the circuit, the measured VSWR was less than 3.1:1 for all frequencies between 100 and 500 MHz. Radiation patterns compared favorably with the predictions. The pattern is isotropic and vertically polarized for frequencies less than 250 MHz. For these frequencies there is a minor null in the elevation pattern at an angle of 30/spl deg/. Most of the energy is directed towards the horizon. Research into the COMWIN vest antenna capable of transmitting or receiving at all frequencies between 30 and 500 MHz is planned. The radiation hazards of using this technology is assessed and mitigated.

A model has been designed that considers water flow as well as electrolyte flow in the two-compartment system consisting of the extracellular and intracellular fluids. The electrolyte flows are assumed to depend only on the electrolyte concentrations, and the water flow is assumed to depend on the electrolyte concentrations as well as the relative and absolute quantities of water. The intake rates are arbitrary, and the coefficients can be varied to simulate diseased conditions. So far, however, there is not sufficient information available to be sure of the normal values. The model does not claim to explain any of the mechanics of the various flows, but only to give the same effects.

An investigation of adiabatic rapid passage has been made in ruby at 8 mm wavelengths. Performance data are given on a two-level ruby maser operated both as a pulsed amplifier and as an oscillator at these wavelengths. When amplifying, values of gain and bandwidth of up to about 14 ds and 10 Mc/ s at 1-4° k were obtained, giving root gain-bandwidth products of up to about 50 Mc/ s. In preliminary experiments using the maser as an oscillator output powers of about 70 / z/ v at 33-1 Gc/ s were obtained at 1. 4° K. The inversion technique used, which incorporates magnetic field modulation with the use of the crystal as a cavity, could be readily scaled to considerably higher frequencies.

The potentialities of microwave spectrometer techniques in assessing the purity and crystalline quality of synthetic maser crystals are illustrated by a comparison of the paramagnetic properties of ruby samples grown from the vapour phase and from powder by flame fusion. Typical spectra presented are discussed in relation to complementary chemical and spectrographic analysis, and it is shown the information obtained is of direct relevance to the accurate control of methods of crystal growth.