3,257 research outputs found
Extreme lattices and vexillar designs
We define a notion of vexillar design for the flag variety in the spirit of
the spherical designs introduced by Delsarte, Goethals and Seidel. For a finite
subgroup of the orthogonal group, we explain how conditions on the group have
the orbits of any flag under the group action be a design and point out why the
minima of a lattice in the sense of the general Hermite constant forming a
4-design implies being extreme. The reasoning proves useful to show the
extremality of many new expected examples (, \La_{24}, Barnes-Wall
lattices, Thompson-Smith lattice for instance) that were out of reach until
now.Comment: 16page
Efficient and Reasonable Object-Oriented Concurrency
Making threaded programs safe and easy to reason about is one of the chief
difficulties in modern programming. This work provides an efficient execution
model for SCOOP, a concurrency approach that provides not only data race
freedom but also pre/postcondition reasoning guarantees between threads. The
extensions we propose influence both the underlying semantics to increase the
amount of concurrent execution that is possible, exclude certain classes of
deadlocks, and enable greater performance. These extensions are used as the
basis an efficient runtime and optimization pass that improve performance 15x
over a baseline implementation. This new implementation of SCOOP is also 2x
faster than other well-known safe concurrent languages. The measurements are
based on both coordination-intensive and data-manipulation-intensive benchmarks
designed to offer a mixture of workloads.Comment: Proceedings of the 10th Joint Meeting of the European Software
Engineering Conference and the ACM SIGSOFT Symposium on the Foundations of
Software Engineering (ESEC/FSE '15). ACM, 201
Teaching Software Engineering through Robotics
This paper presents a newly-developed robotics programming course and reports
the initial results of software engineering education in robotics context.
Robotics programming, as a multidisciplinary course, puts equal emphasis on
software engineering and robotics. It teaches students proper software
engineering -- in particular, modularity and documentation -- by having them
implement four core robotics algorithms for an educational robot. To evaluate
the effect of software engineering education in robotics context, we analyze
pre- and post-class survey data and the four assignments our students completed
for the course. The analysis suggests that the students acquired an
understanding of software engineering techniques and principles
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