Theses and Dissertations

It is the intent of this paper to analyze and evaluate the advantages of on-line computer systems and identity the principles by which a system might be conceived and assembled.

This paper describes a system that tests magnetic memories, digitalizes the sampled memory output, stores the data on magnetic tape, and reduces the data to usable form.

A number of methodshave been proposed for the measurement of resistivity of semiconductors over the past few years. Most prominent are the microwave, A.C. four-point probe, and D.C. four-point probe method.

The electromagnetic properties of a live biological system are extremely important to many medical applications. While information about electromagnetic properties of tissues are available in the literature, little or no data are available for a single cell or subcellular structures. Microwave biological/cell detection has been demonstrated to be useful and promising in many medical applications due to its internal properties such as non-invasive, fast and label-free.

A detailed analysis of experimental meter reading systems, in terms of the generic componenets, has lead the author to conclude that systems which employ ordinary telephone lines as the meter reading data channel aremore economical than systems which depend upon power lines, pilot wires, or radio for communications. This conclusion, however, is based on the assumption that the American Telephone and Telegraph Co., which supplies about 80% of the telephone service in the United States, will soon file for a new, lower monthly charge tariff with the F.C.C.

The reverse recovery time of a diode will be defined in terms of the time required for a specified reverse current transient in the diode circuit to decay to particular value. This transient is important to the designers of fast switching circuits, such as those used in high speed computers, because it represents an upper limit to the switching speed of the diode.

The feasibility of using field-effect transistors in wide-band differential amplifier applications has been investigated. An analysis of bipolar transistor differential amplifiers is included which demonstrates the problem of thermal drift and low input impedance present in all low level transistor amplifiers. An investigation of a field-effect transistor shows that such a device possesses the properties of zero thermal drift at a particular bias point, extremely high input impedance, good radiation resistance, low noise, and a high power gain.

For the first time, the impedance spectrum of live Jurkat T-lymphocytes human cells was characterized in a single sweep spanning six decades of frequency from 9 kHz to 9 GHz. The ultrawide bandwidth bridged the traditional impedance spectroscopy at kilohertz to megahertz frequencies with the recently developed microwave dielectric spectroscopy, which can probe the cell interior without being hindered by the cell membrane.

This paper will prove that the realization of any transfer admittance can always be performed simultaneously with the realization of any pair of R-C driving point short-circuit admittances. The only condition is that the given Y11, Y12, and Y22 have the same poles.

A pulse counter using tunnel diodes and an avalanche transistor has been designed and constructed. A pulse counter was designed to operate on pulses of two nanoseconds duration.

The objective is to obtain a practical method of synthesizing RC Active Filters using transistors as the active element.

Thin films circuits which require inductive elements are more expensive to fabricate because of additional process steps required.

A closed-loop capacitance sensing and control mix-mode circuit with a dedicated sensor electrode and a proportional-integral controller was designed for MEMS varactors. The control was based on tuning the bias magnitude of the MEMS varactor according to t

For the first time, wafer-scale fabrication of PtSe2 MOSFETs was demonstrated by photolithography. The on PtSe2 is grown by thermally assisted conversion (TAC) of Pt films under Se vapor at 400 °C. Taking advantage of the unique property of PtSe2 to transition from semiconductor to semimetal as its thickness increases beyond a few monolayers, channel recess was adapted for improving gate control while keeping the contact resistance as low as 0.008 Ω∙cm. The wafer-scale fabrication resulted in uniform device characteristics so that average vs. best results were reported, as well as RF vs.

A review is made of the operational aspects of the two basic core logic circuits used. Some of the shortcomings of these two circuits initiated consideration of other ferrite switching devices such as the transfluxor.