95,336 research outputs found
The MeshRouter Architecture
The Joint Forces Command (JFCOM) Experimentation Directorate (J9)'s recent Joint Urban Operations (JUO)
experiments have demonstrated the viability of Forces Modeling and Simulation in a distributed environment. The
JSAF application suite, combined with the RTI-s communications system, provides the ability to run distributed
simulations with sites located across the United States, from Norfolk, Virginia to Maui, Hawaii. Interest-aware
routers are essential for communications in the large, distributed environments, and the current RTI-s framework
provides such routers connected in a straightforward tree topology. This approach is successful for small to medium
sized simulations, but faces a number of significant limitations for very large simulations over high-latency, wide
area networks. In particular, traffic is forced through a single site, drastically increasing distances messages must
travel to sites not near the top of the tree. Aggregate bandwidth is limited to the bandwidth of the site hosting the
top router, and failures in the upper levels of the router tree can result in widespread communications losses
throughout the system.
To resolve these issues, this work extends the RTI-s software router infrastructure to accommodate more
sophisticated, general router topologies, including both the existing tree framework and a new generalization of the
fully connected mesh topologies used in the SF Express ModSAF simulations of 100K fully interacting vehicles.
The new software router objects incorporate the scalable features of the SF Express design, while optionally using
low-level RTI-s objects to perform actual site-to-site communications. The (substantial) limitations of the original
mesh router formalism have been eliminated, allowing fully dynamic operations. The mesh topology capabilities
allow aggregate bandwidth and site-to-site latencies to match actual network performance. The heavy resource load at
the root node can now be distributed across routers at the participating sites
Towards A Theory-Of-Mind-Inspired Generic Decision-Making Framework
Simulation is widely used to make model-based predictions, but few approaches
have attempted this technique in dynamic physical environments of medium to
high complexity or in general contexts. After an introduction to the cognitive
science concepts from which this work is inspired and the current development
in the use of simulation as a decision-making technique, we propose a generic
framework based on theory of mind, which allows an agent to reason and perform
actions using multiple simulations of automatically created or externally
inputted models of the perceived environment. A description of a partial
implementation is given, which aims to solve a popular game within the
IJCAI2013 AIBirds contest. Results of our approach are presented, in comparison
with the competition benchmark. Finally, future developments regarding the
framework are discussed.Comment: 7 pages, 5 figures, IJCAI 2013 Symposium on AI in Angry Bird
Framework for Dynamic Evaluation of Muscle Fatigue in Manual Handling Work
Muscle fatigue is defined as the point at which the muscle is no longer able
to sustain the required force or work output level. The overexertion of muscle
force and muscle fatigue can induce acute pain and chronic pain in human body.
When muscle fatigue is accumulated, the functional disability can be resulted
as musculoskeletal disorders (MSD). There are several posture exposure analysis
methods useful for rating the MSD risks, but they are mainly based on static
postures. Even in some fatigue evaluation methods, muscle fatigue evaluation is
only available for static postures, but not suitable for dynamic working
process. Meanwhile, some existing muscle fatigue models based on physiological
models cannot be easily used in industrial ergonomic evaluations. The external
dynamic load is definitely the most important factor resulting muscle fatigue,
thus we propose a new fatigue model under a framework for evaluating fatigue in
dynamic working processes. Under this framework, virtual reality system is
taken to generate virtual working environment, which can be interacted with the
work with haptic interfaces and optical motion capture system. The motion
information and load information are collected and further processed to
evaluate the overall work load of the worker based on dynamic muscle fatigue
models and other work evaluation criterions and to give new information to
characterize the penibility of the task in design process.Comment: International Conference On Industrial Technology, Chengdu : Chine
(2008
Knowledge-based Expressive Technologies within Cloud Computing Environments
Presented paper describes the development of comprehensive approach for
knowledge processing within e-Sceince tasks. Considering the task solving
within a simulation-driven approach a set of knowledge-based procedures for
task definition and composite application processing can be identified. This
procedures could be supported by the use of domain-specific knowledge being
formalized and used for automation purpose. Within this work the developed
conceptual and technological knowledge-based toolbox for complex
multidisciplinary task solv-ing support is proposed. Using CLAVIRE cloud
computing environment as a core platform a set of interconnected expressive
technologies were developed.Comment: Proceedings of the 8th International Conference on Intelligent
Systems and Knowledge Engineering (ISKE2013). 201
The evaluation of an active networking approach for supporting the QOS requirements of distributed virtual environments
This paper describes work that is part of a more general investigation into how Active Network ideas
might benefit large scale Distributed-Virtual-Environments (DVEs). Active Network approaches have been
shown to offer improved solutions to the Scalable Reliable Multicast problem, and this is in a sense the lowest
level at which Active Networks might benefit DVEs in supporting the peer-to-peer architectures considered
most promising for large scale DVEs. To go further than this, the key benefit of Active Networking is the ability
to take away from the application the need to understand the network topology and delegate the execution of
certain actions, for example intelligent message pruning, to the network itself. The need to exchange geometrical
information results in a type of traffic that can place occasional, short-lived, but heavy loads on the network.
However, the Level of Detail (LoD) concept provides the potential to reduce this loading in certain circumstances.
This paper introduces the performance modelling approach being used to evaluate the effectiveness of
active network approaches for supporting DVEs and presents an evaluation of messages filtering mechanisms,
which are based on the (LoD) concept. It describes the simulation experiment used to carry out the evaluation,
presents its results and discusses plans for future work
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