Introductory Circuit Research Articles

Introductory circuits: reference node r model impact

The impact of presenting the r model as a design tool to undergraduates within the introductory circuits course is reported. Classroom use of the r model permits integration of network topology principles and network diagnosis techniques, including modeling-simulation-construction-test. Corresponding laboratory use of the r model permits more effective utilization of instrumentation including spectrum and network analyzers.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Proof of M/sub 12/=M/sub 21/ based on stored energy is incorrect

The mutual inductances for a pair of coupled coils are described by a single parameter M instead of two parameters M/sub 12/ and M/sub 21/. Correct proofs of M/sub 12/=M/sub 21/ can be found in books on physics, electromagnetic field theory, and circuit theory written decades ago. In recent years, some authors of textbooks for introductory linear circuit analysis have presented an alternative proof which is seemingly simple, but is actually unsound. The flaw of the proof is shown and a proof based on the calculation of the average power is presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Multiple choice testing: This type of testing in introductory circuit analysis has proven successful at the University of Illinois

Once upon a time there was a young faculty member in electrical engineering who with two other faculty members had responsibility for teaching the introductory sophomore-level circuit analysis course to 500 students. In order to treat the students uniformly it was established that all students would take the same examinations. Feeling bold, this young assistant professor offered to grade the most difficult problem on the first hour test. Much to his chagrin this grading task required a full 20 hours. Much to my chagrin, this faculty member was I! Subsequently I was able to devise meaningful problems that could be more efficiently graded, but in no case was I able to reduce the grading time for a single problem to less than 10 hours (slightly more than one minute per problem per student).

On the Presentation of Miller's Theorem

Miller's theorem is an important analysis tool. Its presentation in many introductory electronic circuits texts often leads to student misunderstandings with regard to its applicability. An alternative presentation that may improve students' understanding is suggested.

Teaching Introductory Circuits Using the Theory of Distributions and the Convolution Algebra

In this paper we describe what we believe to be an innovation in the teaching of electrical engineering, that is the use of the theory of distributions and the convolution algebra in an introductory circuits course. Teaching the course in this way eliminates the contradiction in the usual defmition of the unit impulse, permits immittance to be defined in the time domain, and facilitates passage from the time domain to the frequency domain. The theory goes far beyond the case of basic circuits and applies to any linear time invariant system. Using distributions, the product of convolution becomes a powerful tool in solving circuit equations; the initial conditions are introduced automatically. It is the authors' belief that in a number of years most linear circuits and systems courses will be taught following the approach presented here.

Computer-Flavored Circuit Theory-Revisited

The impact of the computer and computation on the introductory circuits courses is examined. In response to this impact, changes that include the analysis of nonlinear circuits and experimentation using APL are recommended for the teaching of the circuits courses.

Coincidence of Poles and Zeros

The concept of poles and zeros of network functions is taught in many introductory circuit courses, but the methods of presentation vary widely. Among them, the introduction of the network function by way of the differential equation written in operational form offers some pedagogical advantages that justify its use in spite of its lack of mathematical rigor. This method also helps to realize that poles and zeros can actually coincide with each other. This is illustrated by an example in which the cancellation of factors in the numerator and denominator of the network function would lead to an error if arbitrary initial conditions are to be satisfied.