Motivated by a wide range of applications, research on agent-based models of contagion propagation over networks has attracted a lot of attention in the literature. Many of the available software systems for simulating such agent-based models require users to download software, build the executable, and set up execution environments. Further, running the resulting executable may require access to high performance computing clusters. Our work describes an open access software system (NetSimS) that works under the “Modeling and Simulation as a Service” (MSaaS) paradigm. It enables users to run simulations by selecting models and parameter values, initial conditions, and networks through a web interface. The system supports a variety of models and networks with millions of nodes and edges. In addition to the simulator, the system includes components that enable users to choose initial conditions for simulations in a variety of ways, to analyze the data generated through simulations, and to produce plots from the data. We describe the components of NetSimS and carry out a performance evaluation of the system. We also discuss two case studies carried out on large networks using the system. NetSimS is a major component within net.science, a cyberinfrastructure for network science.
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Harvesting Wasted Clock Cycles for Efficient Online Testing
Mission-critical systems often require some testing
to occur while the system is running. In many cases, this involves
taking parts of the system off-line temporarily to apply the tests.
However, hazards that occur during regular processor execution
require the addition of stall cycles to maintain program correctness.
These stall cycles generally perform no other function.
In this paper, we focus on testing the ALU during those stall
cycles to identify new errors or defects that arise during program
execution due to aging and increased temperature that may slow
down the circuitry or cause permanent defects. We investigate
the time to detection of a fault (both stuck-at and transition)
that may have caused silent data corruption. In addition, we
identify the relationship between the programs running and the
list of functional faults and how this impacts the test set length.
Finally, we discuss area and performance impacts for the physical
implementation of the approach.
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- NSF-PAR ID:
- 10473502
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- 2023 IEEE European Test Symposium
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Location:
- Venezia, Italy
- Sponsoring Org:
- National Science Foundation
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