Search results for "Distributed"
showing 10 items of 1260 documents
The Holonic Production System: a Multi Agent Simulation Approach
2010
Today’s turbulent markets are facing unpredictable and sudden variations in demand. In this context, the Holonic Production System (HPS) seems to be able to overcome the operational and economic problems of traditional production systems. The HPS’ ability to adapt and react to business environment changes, whilst maintaining systemic synergies and coordination, leverage on its network organizational structure, assuring both flexibility and profitability. In this paper we study HPS experimentally, modeling holon-firms as agents. In our simulation, holon-firms interact both with each other and with the external environment without predetermined hierarchies and following their own aims and int…
Distributed Symbolic Network Quality Assessment for Resource-constrained Devices
2021
After a Wireless Sensor Network (WSN) is deployed it is subject to significant variations of the quality of its radio links during its lifetime. Knowledge of the condition of the wireless links can be useful to optimize power consumption and increase the reliability of the network. However, resource-constrained nodes may not be able to spare the storage space for network monitoring code. Also, reprogramming deployed nodes can be costly or unfeasible. In this work, we show how an approach based on the exchange of symbolic executable code among nodes enables the assessment of the network status in terms of Packet Reception Rate (PRR) with no extra storage requirements on deployed networks. We…
Fuzzy Logic based model for self-optimizing energy consumption in IoT environment
2021
Energy optimization is essential in IoT environments due to energy constraints for some IoT components. In fact, energy consumption has a direct impact on IoT system lifetime, which represents an important Quality of Service (QoS) parameter for IoT environments. In order to extend the IoT system lifetime, energy consumption optimization should be considered in several IoT components. In this paper, we specify an energy self-optimizing mechanism allowing to minimize data transmission energy consumption of IoT objects. This mechanism enables selecting specific objects to send the desired data while minimizing the energy consumed for the corresponding communication. Our proposal is made of a M…
Efficient anomaly detection on sampled data streams with contaminated phase I data
2020
International audience; Control chart algorithms aim to monitor a process over time. This process consists of two phases. Phase I, also called the learning phase, estimates the normal process parameters, then in Phase II, anomalies are detected. However, the learning phase itself can contain contaminated data such as outliers. If left undetected, they can jeopardize the accuracy of the whole chart by affecting the computed parameters, which leads to faulty classifications and defective data analysis results. This problem becomes more severe when the analysis is done on a sample of the data rather than the whole data. To avoid such a situation, Phase I quality must be guaranteed. The purpose…
Distributed Computing on Distributed Memory
2018
Distributed computation is formalized in several description languages for computation, as e.g. Unified Modeling Language (UML), Specification and Description Language (SDL), and Concurrent Abstract State Machines (CASM). All these languages focus on the distribution of computation, which is somewhat the same as concurrent computation. In addition, there is also the aspect of distribution of state, which is often neglected. Distribution of state is most commonly represented by communication between active agents. This paper argues that it is desirable to abstract from the communication and to consider abstract distributed state. This includes semantic handling of conflict resolution, e.g. i…
Energy-Efficient Context-Aware Resource Allocation for Edge-Computing-Empowered Industrial IoT
2020
Edge computing provides a promising paradigm to support the implementation of industrial Internet of Things (IIoT) by offloading computational-intensive tasks from resource-limited machine-type devices (MTDs) to powerful edge servers. However, the performance gain of edge computing may be severely compromised due to limited spectrum resources, capacity-constrained batteries, and context unawareness. In this chapter, we consider the optimization of channel selection which is critical for efficient and reliable task delivery. We aim at maximizing the long-term throughput subject to long-term constraints of energy budget and service reliability. We propose a learning-based channel selection fr…
Context-Aware RF-Energy Harvesting for IoT Networks
2021
Energy Harvesting plays a crucial role in improving the operational lifetime of IoT devices. The deployment of dedicated RF-transmitters helps in sufficient energy propagation to the sensor nodes of IoT networks. Also, energy harvesting using the deployment of such RF-transmitters is a challenging issue. In this work, two methods are proposed for the optimal placement of RF-transmitters for efficient energy harvesting in wireless sensor networks. The proposed context-aware RF-energy harvesting considers different network performance parameters such as energy-hole information, and data routing information. RF-transmitter deployment is achieved using network connectivity information in the fi…
A Comparison Study of Metaheuristic Techniques for Providing QoS to Avatars in DVE Systems
2004
Network-server architecture has become a de-facto standard for Distributed Virtual Environment (DVE) systems. In these systems, a large set of remote users share a 3D virtual scene. In order to design scalable DVE systems, different approaches have been proposed to maintain the DVE system working under its saturation point, maximizing system throughput. Also, in order to provide quality of service to avatars in a DVE systems, avatars should be assigned to servers taking into account, among other factors, system throughput and system latency. This highly complex problem is called quality of service (QoS) problem in DVE systems. This paper proposes two different approaches for solving the QoS…
The role of the Access Point in Wi-Fi networks with selfish nodes
2009
In Wi-Fi networks, mobile nodes compete for accessing the shared channel by means of a random access protocol called Distributed Coordination Function (DCF), which is long term fair. But recent drivers allow users to configure protocol parameters differently from their standard values in order to break the protocol fairness and obtain a larger share of the available bandwidth at the expense of other users. This motivates a game theoretical analysis of DCF. Previous studies have already modeled access to a shared wireless channel in terms of non-cooperative games among the nodes, but they have mainly considered ad hoc mode operation. In this paper we consider the role of the Access Point (AP…
Continuous energy-efficient monitoring model for mobile ad hoc networks
2021
The monitoring of mobile ad hoc networks is an observation task that consists of analysing the operational status of these networks while evaluating their functionalities. In order to allow the whole network and applications to work properly, the monitoring task has become of considerable importance. It must be carried out in real-time by performing measurements, logs, configurations, etc. However, achieving continuous energy-efficient monitoring in mobile wireless networks is very challenging considering the environment features as well as the unpredictable behavior of the participating nodes. This paper outlines the challenges of continuous energy-efficient monitoring over mobile ad hoc n…