4,298 research outputs found
An Algorithmic Framework for Labeling Network Maps
Drawing network maps automatically comprises two challenging steps, namely
laying out the map and placing non-overlapping labels. In this paper we tackle
the problem of labeling an already existing network map considering the
application of metro maps. We present a flexible and versatile labeling model.
Despite its simplicity, we prove that it is NP-complete to label a single line
of the network. For a restricted variant of that model, we then introduce an
efficient algorithm that optimally labels a single line with respect to a given
weighting function. Based on that algorithm, we present a general and
sophisticated workflow for multiple metro lines, which is experimentally
evaluated on real-world metro maps.Comment: Full version of COCOON 2015 pape
Optimum Placement of Post-1PN GW Chirp Templates Made Simple at any Match Level via Tanaka-Tagoshi Coordinates
A simple recipe is given for constructing a maximally sparse regular lattice
of spin-free post-1PN gravitational wave chirp templates subject to a given
minimal match constraint, using Tanaka-Tagoshi coordinates.Comment: submitted to Phys. Rev.
Autonomous Deployment of a Solar Panel Using an Elastic Origami and Distributed Shape Memory Polymer Actuators
Deployable mechanical systems such as space solar panels rely on the
intricate stowage of passive modules, and sophisticated deployment using a
network of motorized actuators. As a result, a significant portion of the
stowed mass and volume are occupied by these support systems. An autonomous
solar panel array deployed using the inherent material behavior remains
elusive. In this work, we develop an autonomous self-deploying solar panel
array that is programmed to activate in response to changes in the surrounding
temperature. We study an elastic "flasher" origami sheet embedded in a circle
of scissor mechanisms, both printed with shape memory polymers. The scissor
mechanisms are optimized to provide the maximum expansion ratio while
delivering the necessary force for deployment. The origami sheet is also
optimized to carry the maximum number of solar panels given space constraints.
We show how the folding of the "flasher" origami exhibits a bifurcation
behavior resulting in either a cone or disk shape both numerically and in
experiments. A folding strategy is devised to avoid the undesired cone shape.
The resulting design is entirely 3D printed, achieves an expansion ratio of
1000% in under 40 seconds, and shows excellent agreement with simulation
prediction both in the stowed and deployed configurations.Comment: 12 pages, 12 figure
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