Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 85).

The requirements imposed upon a d.c. amplifier and reference voltage supply, suitable for measurement and control of signals of the order of 1 volt to an accuracy of 10 parts per million are investigated. A basic block design is proposed to achieve this goal using a transistor differential amplifier of new design and a highly regulated reference voltage supply. The detailed design procedure for these building blocks is then presented. Exact analysis of important characteristics of several relevant circuit configurations is presented. The unit under discussion was constructed and the measured performance was found to be in good agreement with the predicted performance. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

An electromagnet capable of producing a magnetic field intensity of greater than 21,600 gauss in a gap of one inch and over an area of 3.14 square inches has been designed and constructed. The structure of the ternary alloy of approximate composition Mn₆ₒAl₂ₒC₂ₒ has been investigated by X-ray methods, and shown to have an ordered perovskite structure, with aₒ = 3,865 A⁰. The effective magnetic moment pit manganese atom was measured, using the electromagnet, and a torsion balance method. The value of the magnetic moment at zero degrees Kelvin was found to be 1.2 Bohr magnetons per manganese atom. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

A seven and one half ton electromagnet has been built primarily for beam analysis in conjunction with the University of British Columbia electrostatic generator. With a current of 49 amperes, a field in excess of 19,900 gauss over an area of 256 square inches has been obtained across a one inch air gap. The hysteresis loop is satisfactorily small, being 0.2 amperes wide at a magnetising current of 15 amperes. Current stability with the magnetising current varying from zero to 35 amperes has "been maintained to a few parts in 10,000 over periods as long as seven hours. Field stability has been checked using a proton resonance signal to be one part in 10,000 over a short period of eight minutes, and to be three parts in 10,000 over the long period of seven hours. Using the stabilising system, the time required to change the field to a new setting is less than three seconds. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Thesis (M.S.)--Rochester Institute of Technology, 1984. / Typescript. Includes bibliographical references (leaf 315).

No description available.

Thesis (M.S.)--Virginia Polytechnic Institute, 1952. / Vita. Includes bibliographical references (leaves 83-85). Also available via the Internet.

Master of Science

This thesis provides an analysis of the diminishing sea ice trend in the Arctic Ocean by examining the NPS 1/12-degree pan-Arctic coupled ice-ocean model. While many previous studies have analyzed changes in ice extent and concentration, this research focuses on ice thickness as it gives a better indication of ice volume variability. The skill of the model is examined by comparing its output to sea ice thickness data gathered during the last two decades. The first dataset used is the collection of draft measurements conducted by U.S. Navy submarines between 1986 and 1999. The second is electromagnetic (EM) induction ice thickness measurements gathered using a helicopter by the Alfred Wegener Institute in April 2003. Last, model output is compared with data collected by NASAâ s ICESat program using a laser altimeter mounted on a satellite of the same name. The NPS model indicates an accelerated thinning trend in Arctic sea ice during the last decade. The validation of model output with submarine, EM and ICESat data supports this result. This lends credence to the postulation that the Arctic not only might, but is likely to be ice-free during the summer in the near future.

In general, contrary to popular opinion. heavy shading coils are not as effective in reducing noise in an alternating current electromagnet as those which are smaller and thus have a greater value of resistance. This occurs because in addition to obtaining the greatest shift possible between flux produced by the unshaded and shaded portions of the pole the magnitudes of these fluxes should be equal. / Master of Science