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OpenVX is a recently ratified standard that was expressly proposed to facilitate the design of computer-vision (CV) applications used in real-time embedded systems. Despite its real-time focus, OpenVX presents several challenges when validating real-time constraints. Many of these challenges are rooted in the fact that OpenVX only implicitly defines any notion of a schedulable entity. Under OpenVX, CV applications are specified in the form of processing graphs that are inherently considered to execute monolithically end-to-end. This monolithic execution hinders parallelism and can lead to significant processing-capacity loss. Prior work partially addressed this problem by treating graph nodes as schedulable entities, but under OpenVX, these nodes represent rather coarse-grained CV functions, so the available parallelism that can be obtained in this way is quite limited. In this paper, a much more fine-grained approach for scheduling OpenVX graphs is proposed. This approach was designed to enable additional parallelism and to eliminate schedulability-related processing-capacity loss that arises when programs execute on both CPUs and graphics processing units (GPUs). Response-time analysis for this new approach is presented and its efficacy is evaluated via a case study involving an actual CV application.
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Reflex Theory, Cautionary Tale: Misleading Simplicity in Early Neuroscience
This paper takes an integrated history and philosophy of science approach to the topic of "simplicity out of complexity". The reflex theory was a framework within early 20th century psychology and neuroscience which aimed to decompose complex behaviours and neural responses into simple reflexes. It was controversial in its time, and did not live up to its own theoretical and empirical ambitions. Examination of this episode poses important questions about the limitations of simplifying strategies, and the relationship between simplification and the engineering approach to biology.
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- Award ID(s):
- 1921821
- PAR ID:
- 10309297
- Editor(s):
- Schickore, Jutta
- Date Published:
- Journal Name:
- Integrated HPS Conference Proceedings
- Volume:
- 1
- Issue:
- 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1007/s11229-021-03351-w
