Letter from William E. Warne to Senator Langer Regarding Depredation by Horses from the Fort Berthold Reservation, Undated

This letter, undated but likely written in the first half of 1950 (see comment), from Assistant Secretary of the United States (US) Department of the Interior William E. Warne to US Senator William Langer, makes reference to Langer\u27s letter of January 12 regarding complaints by H. A. Rustad and Julius Mattson of crop damage caused by wild horses belonging to the Fort Berthold Reservation. Warne writes that an investigation was made into the matter, that the Fort Berthold Agency Superintendent has been aware of the problem for some time, and that past efforts to resolve the problem have met with limited success. Recent talks with the Tribes, however, have indicated an awareness and willingness on the Tribes\u27 part to deal with the problem, and recently 227 head of horses were sold, with plans to sell more. Furthermore, representatives of the US Bureau of Indian Affairs Area Office and of the Fort Berthold Agency have spoken with Mattson. From their report, Warne feels that the cooperative effort of the parties concerned will result in a satisfactory solution of the problem. Note: While this letter is undated, Warne served as Assistant Secretary of the US Department of the Interior only from 1947 to 1951, and there are references in the Usher Burdick Collection to complaints by H. A. Rustad of horse depredation in January of 1950, which, combined with references in this letter to complaints made in January, suggests, albeit inconclusively, that this letter was written in the first part of 1950. See also: Letter from Representative Burdick to H. A. Rustad Regarding Troubles with Reservation Horses, January 18, 1950 (In the Usher Burdick Collection) Letter from Representative Burdick to the U.S. Bureau of Indian Affairs Regarding Troubles with Reservation Horses, January 18, 1950 (In the Usher Burdick Collection)https://commons.und.edu/langer-papers/2069/thumbnail.jp

Dipole radiation from a cylindrical hole in the earth.

This report examines the problem of an antenna radiating from a cylindrical hole in the earth and the subsequent far-zone field produced in the upper air half space. The approach used for this analysis was to first examine propagation characteristics along the hole for surrounding geologic material properties. Three cases of sand with various levels of moisture content were considered as the surrounding material to the hole. For the hole diameters and sand cases examined, the radiation through the earth medium was found to be the dominant contribution to the radiation transmitted through to the upper half-space. In the analysis presented, the radiation from a vertical and a horizontal dipole source within the hole is used to determine a closed-form expression for the radiation in the earth medium which represents a modified element factor for the source and hole combination. As the final step, the well-known results for a dipole below a half space, in conjunction with the use of Snell's law to transform the modified element factor to the upper half space, determine closed-form expressions for the far-zone radiated fields in the air region above the earth

Joint voltages resulting from lightning currents.

Simple formulas are given for the interior voltages appearing across bolted joints from exterior lightning currents. External slot and bolt inductances as well as internal slot and bolt diffusion effects are included. Both linear and ferromagnetic wall materials are considered. A useful simplification of the slot current distribution into linear stripline and cylindrical parts (near the bolts) allows the nonlinear voltages to be estimated in closed form

Capacitance and effective area of flush monopole probes.

Approximate formulas are constructed and numerical simulations are carried out for electric field derivative probes that have the form of flush mounted monopoles. Effects such as rounded edges are included. A method is introduced to make results from two-dimensional conformal mapping analyses accurately apply to the three-dimensional axisymmetric probe geometr

An improved statistical model for linear antenna input impedance in an electrically large cavity.

This report presents a modification of a previous model for the statistical distribution of linear antenna impedance. With this modification a simple formula is determined which yields accurate results for all ratios of modal spectral width to spacing. It is shown that the reactance formula approaches the known unit Lorentzian in the lossless limit

Loop-to-loop coupling.

This report estimates inductively-coupled energy to a low-impedance load in a loop-to-loop arrangement. Both analytical models and full-wave numerical simulations are used and the resulting fields, coupled powers and energies are compared. The energies are simply estimated from the coupled powers through approximations to the energy theorem. The transmitter loop is taken to be either a circular geometry or a rectangular-loop (stripline-type) geometry that was used in an experimental setup. Simple magnetic field models are constructed and used to estimate the mutual inductance to the receiving loop, which is taken to be circular with one or several turns. Circuit elements are estimated and used to determine the coupled current and power (an equivalent antenna picture is also given). These results are compared to an electromagnetic simulation of the transmitter geometry. Simple approximate relations are also given to estimate coupled energy from the power. The effect of additional loads in the form of attached leads, forming transmission lines, are considered. The results are summarized in a set of susceptibility-type curves. Finally, we also consider drives to the cables themselves and the resulting common-to-differential mode currents in the load

Analysis of electromagnetic scattering by nearly periodic structures: an LDRD report.

In this LDRD we examine techniques to analyze the electromagnetic scattering from structures that are nearly periodic. Nearly periodic could mean that one of the structure's unit cells is different from all the others--a defect. It could also mean that the structure is truncated, or butted up against another periodic structure to form a seam. Straightforward electromagnetic analysis of these nearly periodic structures requires us to grid the entire structure, which would overwhelm today's computers and the computers in the foreseeable future. In this report we will examine various approximations that allow us to continue to exploit some aspects of the structure's periodicity and thereby reduce the number of unknowns required for analysis. We will use the Green's Function Interpolation with a Fast Fourier Transform (GIFFT) to examine isolated defects both in the form of a source dipole over a meta-material slab and as a rotated dipole in a finite array of dipoles. We will look at the numerically exact solution of a one-dimensional seam. In order to solve a two-dimensional seam, we formulate an efficient way to calculate the Green's function of a 1d array of point sources. We next formulate ways of calculating the far-field due to a seam and due to array truncation based on both array theory and high-frequency asymptotic methods. We compare the high-frequency and GIFFT results. Finally, we use GIFFT to solve a simple, two-dimensional seam problem