In this Fall 2008 issue of ACM Crossroads, we continue to explore student
work and professional viewpoints across the spectrum of computer
science research and development. Whether your interests are in graphics, theory, or systems, you will be certain to find articles to expand your
knowledge or introduce new perspectives on ongoing work.
by Justin Solomon, Managing Editor
First, demonstrating the power of motion planning and other artificial intelligence methods, Salik Syed of Stanford University presents
his experiments writing a program to plan the path of a skateboarder.
In his article, entitled “Motion Planning for Skateboard-Like Robots
in Dynamic Environments,” he demonstrates how computers can plan
efficient paths for skateboards through half pipes, ramps, and other
obstacles in a reasonable amount of time. The results of the study
suggest that the algorithms and heuristics used to plan skateboard
paths could be applied to larger and more complex robotics problems.
Moving from artificial intelligence to systems, Joe Bungo of ARM
presents his research into optimizing programs for space or time efficiency in an article entitled “The Use of Compiler Optimizations for
Embedded Systems Software.” By developing a consistent methodology
for choosing combinations of compiler flags and other options, Joe is
able to achieve smaller program sizes or faster run times without changing a significant amount of code. His research reveals that writing efficient software requires not only algorithmic insight, but also a firm grasp
of the features and inner workings of the compiler converting human-readable programs into machine-readable code.
The final research paper to appear in this issue of Crossroads
comes from the fields of computer graphics and modeling. Contributed by James Hegarty of Stanford University, this paper, entitled
“Geometric and Path Tracing Methods for Simulating Light Transport through Volumes of Water Particles,” explores methods for rendering fog, clouds, and other water droplet phenomena. The
methods James describes allow him to draw detailed scenes involving
rainbows, waterfalls, and other features from nature.
Finally, Ed DeHart of East Carolina University introduces the history and basic concepts of encryption in his article, “Data Encryption:
Mixing Up the Message in the Name of Security.” The foundations Ed
describes certainly will continue increasing in importance as services
handling private or sensitive information move to the internet.
As usual, all the research papers, tutorials, and other articles you
see in this issue are contributed by Crossroads readers. If you
recently have completed a research project, finished making a large
piece of software, or simply would like to share your knowledge of
some aspect of computer science, please consider submitting. We
accept submissions on a rolling basis, so feel free to send us your contribution at any time. For specifics about the submission process,
check our website, at http://www.acm.org/crossroads. When you are
ready to submit, you can email your article to our editing staff, at
Also, with the new publishing season we continue to change
Crossroads to suit your interests in programming and computer science.
If you have ideas for additional
improvements or if you would like
to participate directly by working
as an associate editor or columnist, be sure to contact us.
We look forward to filling the 2008-2009 academic year with
intriguing new articles from a variety of perspectives in computer
science. In the meantime, best of luck as you begin a new year of
classes, research, or programming.
Justin Solomon ( firstname.lastname@example.org) is an undergraduate at
Stanford University double majoring in computer science and mathematics. Along with his work as the managing editor for ACM Crossroads,
he participates in computer graphics research in collaboration with the
Stanford Department of Computer Science and Pixar Animation Studios, competes in programming contests, and plays cello and piano.
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