Charles Slivinsky

Computer-access security systems using keystroke dynamics

An approach to securing access to computer systems is described. By performing real-time measurements of the time durations between the keystrokes when a password is entered and using pattern-recognition algorithms, three online recognition systems were devised and tested. Two types of passwords were considered: phrases and individual names. A fixed phrase was used in the identification system. Individual names were used as a password in the verification system and in the overall recognition system. All three systems were tested and evaluated. The identification system used 10 volunteers and gave an indecision error of 1.2%. The verification system used 26 volunteers and gave an error of 8.1% in rejecting valid users and an error of 2.8% in accepting invalid users. The overall recognition system used 32 volunteers and gave an error of 3.1% in rejecting valid users and an error of 0.5% in accepting invalid users. >

Networked, asynchronous assessment of ongoing instruction

A system for anonymous assessment of ongoing instruction by students is being implemented and used in an undergraduate electrical engineering course on circuit theory. Students submit their detailed assessments through a conferencing system, topic-by-topic as the course proceeds. An intermediary is used to provide anonymity and verification. The teacher receives the assessments forwarded by the intermediary and then posts responses. The system provides a means for obtaining regular, structured feedback about classroom instruction using a fixed-format questionnaire. It is asynchronous and requires almost no use of class time. Students are required to participate and are given a small amount of credit towards their course grade. Reasonable deadlines and the asynchronous operation provide flexibility and yet allow feedback in-time to improve ongoing instruction. This topic-specific feedback on classroom instruction and other course work provides the type of detailed information from enrolled students needed to evaluate and improve the course and the instruction.

Computation of secondary arc current on double-circuit EHV lines employing single-pole switching

Abstract Successful selective- (or single-) pole switching (SPS) of faulted EHV transmission lines depends on rapid secondary arc extinction. Two factors which govern the probability of secondary arc extinction are the effective value of the steady-state secondary arc current and the rate of rise of the recovery voltage. Successful application of SPS requires that the magnitude of the secondary arc current should be kept below a certain level. The purpose of this work is to present a method for the computation of the effective value of the secondary arc current on a double-circuit transmission line employing SPS. The model developed for the double-circuit line takes into account the mutual coupling between the two individual circuits. A typical 400 kV double-circuit line is considered and the effective value of the secondary arc current is evaluated for both transposed and untransposed configurations of the line. Then a comparison with the results available from simple network analysis is made.

A consultation with EE faculty advisors: Good academic counseling can make all the difference to your college — And professional — Careers

Academic counseling has notoriously been one aspect of college life that is not given the attention it deserves. However, its importance for students cannot be overemphasized. Faculty advisors must not only insure that their students fulfill all the requirements for graduation, but also help them choose courses, including electives (technical and non-technical). Good advice, when taken, produces well-rounded technical graduates with multifaceted capabilities such as breadth of vision, the ability to analyze and solve problems, and sound communication and interpersonal skills. Bad advice (or good advice not taken) leads to opportunities lost and gaps in a persons education that may never be filled.

Educational opportunities in telecommunications beckon EEs: A promising career in this high-growth field can begin with a university program that offers specialized training

The field of telecommunications promises to be one of the areas offering the hottest career opportunities in the next several years, and experts are predicting shortages of trained personnel. Engineers will be needed to design, build, and manage the communications networks and services needed by industrial companies, banks, credit card companies, and the military — to mention just a few of the major users.

Digital signal processing: An individual learning package: ILPs are like university courses in that they are built around engineering texts, but to make up for not having a prof, they include other specially prepared materials

The IEEE Educational Activities Board is sponsoring the development of Individual Learning Packages (ILPs) which are available to IEEE members at a discount. These ILPs can be studied by engineers to stay up-to-date in technical specialties within electrical and computer engineering.

Editorial: Potentials: A new beginning

Potentials is in its fourth year of operation, and has reached, in an important sense, the end of its beginnings. A new slate of people are now in place to maintain the tradition of excellence that has been established.

Books — Digital signal processing: First, an overview; then a survey of the basic texts

The field of digital signal processing originated in the 1960s and accelerated in growth in the 1970s. It includes several basic operations on signals: reconstruction of signals from samples, analysis of the characteristics of signals, and signal filtering. Signal reconstruction refers to the operation of reforming a continuously varying signal, such as a voltage, a speed measurement, and other factors, from a set of evenly spaced samples of the signal.

A microcomputer-based controller for a single-phase, 2 HP DC motor drive

This paper describes a microcomputer-based controller for a single-phase, 2-HP DC motor drive. Hardware, software, and systems aspects are discussed. Alternative control algorithms are presented. Results of system operation are given.