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DU2SL YouTube Channel

The DU2SL YouTube channel is now available:

Please check it out for videos of recent demos and autonomous unmanned vehicles.

Kav Shrestha Successfully Defends MS Thesis

On February 22, 2010, Kav Shrestha, a Ph.D. student working with me, successfully defended his MS Thesis entitled "An Empirical Evaluation of the Effectiveness of JML Assertions as Test Oracles". Committee members were Dr. Mohammad Mahoor (, Dr. Susanne Sherba ( and myself.


Test oracles remain one of the least understood aspects of the modern testing process.
An oracle is a mechanism used by software testers and software engineers for
determining whether a test has passed or failed. One widely-supported approach to
oracles is the use of runtime assertion checking during the testing activity. Method
invariants, pre- and postconditions help detect bugs during runtime. While assertions
are supported by virtually all programming environments, are used widely in practice,
and are often assumed to be effective as test oracles, there are few empirical studies
of their efficacy in this role. In this thesis, we present the results of an experiment we
conducted to help understand this question. To do this, we studied seven of the core
Java classes that had been annotated by others with assertions in the Java Modeling
Language, used the muJava mutation analysis tool to create mutant implementations
of these classes, exercised them with input-only (i.e., no oracle) test suites that
achieve branch coverage, and used a machine learning tool, Weka, to determine which
annotations were effective at “killing” these mutants. We also evaluate how effective
the “null oracle”(in our case, the Java runtime system) is at catching these bugs. The
results of our study are interesting, and help provide software engineers with insight
into situations in which assertions can be relied upon to find bugs, and situations in
which assertions may need to be augmented with other approaches to test oracles.

DUP Paper accepted at the 43rd Annual Simulation Symposium (ANSS'10)

A paper, entitled "Simplifying Parallel and Distributed Simulation with the DUP System" was recently accepted for publication at the 43rd Annual Simulation Symposium (ANSS'10).

Full bibliographic information, along with the abstract and PDF is available:

Please see for further information about The DUP System.