45th Arkansas Junior Science and Humanities Symposium


Lightening Flashes

Dr. Mostafa Hemmati, Professor of Physics (Arkansas Tech University)

Breakdown waves are propagating processes which convert an ion-less gas into a neutral plasma.  The return stroke of a lightening flash is an example of a breakdown wave.  For the theoretical investigation of the waves, we employ a one-dimensional, steady-state, constant-velocity fluid model.  The wave is considered to be shock-fronted and electrons are the main element in the propagation of the wave.  A qualitative description of what happens in a lightening bolt will be provided.  Only a special type of lightening, a cloud with a negative bottom over a flat country, will be considered.

Dr. Hemmati earned his Ph.D. in physics from the University of Oklahoma in 1983.  In the fall semester of 1983, he was employed as an assistant professor of physics at Arkansas Tech University.  Currently, he serves as a professor of physics and the director of the Office of Undergraduate Research at Arkansas Tech University.  His research interests are in the theoretical investigation of electric breakdown waves.  He has made numerous presentations at national and international conferences, submitted over fifty successful grant proposals, and published over sixty peer-reviewed papers in scholarly journals.


Jominy Hardenability of Steel

Dr. Bob Frasier, Associate Professor of Mechanical Engineering (Arkansas Tech University)

The process of hardening steel and the Jominy Hardness Test will be explained and demonstrated.  A pre-heated specimen of steel will be cooled in a Jominy End Quench jig and the significance and mechanism of the hardness test will be explained

Engineering from the Atomic Scale to the Blimp Scale

Dr. Daniel Bullock, Associate Professor of Electrical Engineering (Arkansas Tech Univerisity)

Electrical engineering is such a broad based area of study ranging the full limit of the scientific prefixes from nanotechnologies to megawatt power production.  Demonstrations of these projects including the Wonder Blimp will delight and inform students

The Digital Revollution

Dr. Carl Greco, Associate Professor of Electrical Engineering (Arkansas Tech University)

The advent of Very Large Scale Integration (VSLI) digital circuits have spawned the digital age impacting everything from signal broadcasting via cell phones and television to space exploration.  Electrical engineering and computer science students in the Digital Logic Laboratories at Arkansas Tech University discover and master the devices and developmental tools that have made these astronomical advances possible.  A timely demonstration guaranteed not to scare or frighten awaits your attention.

Mobile Robot Algorithms

Dr. Carlos Castillo, Assistant Professor of Electrical Engineering (Arkansas Tech University)

The pololu 3pi is one of the best affordable off-the-shelf mobile robots available at the present time.  The undergraduate program in the Department of Electrical Engineering at Arkansas Tech University includes the course ELEG 3133, Microprocessor Design, in which student learn to program these robots.  Following the line, maze solver, and arbitrary sequences are some of the algorithms implemented/modified by the students.  A presentaion of these algorithms will be given.

Scanning Electron Microscope

Mr. Stan Apple, Instructor of Mechanical Engineering (Arkansas Tech University)

The scanning electron microscope (SEM) is one of the most versatile instruments available for the examination and analysis of the microstructure of solid objects.  In addition, it can be used to examine and analyze biological samples.  A 1018 oven-cooled, heat-treated steel sample showing iron carbide regions in a ferrite matrix will be examined.  Finally, a biological specimen will be viewed after having been coated with gold.