Search results for " Network"
showing 10 items of 6428 documents
An Efficient Retransmission Strategy for Data Gathering in Wireless Sensor Networks Authors
2005
This paper introduces a new strategy for data gathering in wireless sensor networks that takes into account the need for both energy saving and for a reasonable tradeoff between robustness and efficiency. The proposed algorithm implements an efficient strategy for retransmission of lost packets by discovering alternative routes and making clever use of multiple paths when necessary; in order to do that we use duplicate and order insensitive aggregation functions, and by taking advantage of some intrinsic characteristics of the wireless sensor networks, we exploit implicit acknowledgment of reception and smart caching of the data.
Adaptive distributed outlier detection for WSNs.
2014
The paradigm of pervasive computing is gaining more and more attention nowadays, thanks to the possibility of obtaining precise and continuous monitoring. Ease of deployment and adaptivity are typically implemented by adopting autonomous and cooperative sensory devices; however, for such systems to be of any practical use, reliability and fault tolerance must be guaranteed, for instance by detecting corrupted readings amidst the huge amount of gathered sensory data. This paper proposes an adaptive distributed Bayesian approach for detecting outliers in data collected by a wireless sensor network; our algorithm aims at optimizing classification accuracy, time complexity and communication com…
VPP: A Communication Schema for Population Protocols in VANET
2021
Population protocols are a new paradigm that aims to model distributed systems composed of randomly interacting mobile agents. The main advantage of this model is that, when certain theoretical assumptions hold, it is possible to formally demonstrate their convergence. We consider the problem of adopting Population Protocols in a real-world scenario that does not guarantee these assumptions. In particular, we consider the application domain of Vehicular Ad-Hoc Networks (VANETs) which are characterized by dynamic network topologies, and where wireless communications can be affected by interferences and errors. In this work, we analyze the main features of VANET agents and the communications …
Embedded Knowledge-based Speech Detectors for Real-Time Recognition Tasks
2006
Speech recognition has become common in many application domains, from dictation systems for professional practices to vocal user interfaces for people with disabilities or hands-free system control. However, so far the performance of automatic speech recognition (ASR) systems are comparable to human speech recognition (HSR) only under very strict working conditions, and in general much lower. Incorporating acoustic-phonetic knowledge into ASR design has been proven a viable approach to raise ASR accuracy. Manner of articulation attributes such as vowel, stop, fricative, approximant, nasal, and silence are examples of such knowledge. Neural networks have already been used successfully as de…
Fuzzy techniques for access and data management in home automation environments
2012
Home Automation Environments are characterized by the integration of electronic devices as well as by the performance of communication and control systems. Environment infrastructure has to meet several requirements including Quality of Service (QoS), safety, security, and energy saving. However, Home Automation deals with complex environments, so that advanced data management systems are required to meet the above constraints. Fuzzy Logic based techniques can be successful used to improve system performance management. This work proposes and describes the use and application of fuzzy rules on a two-tiered architecture integrating a biometric authentication module and communication real-tim…
A scalable platform for safe and secure decentralized traffic management of multiagent mobile systems
2006
In this paper we describe the application of wireless sensor networking techniques to address the realization of a safe and secure decentralized traffic management system. We consider systems of many heterogeneous autonomous vehicles moving in a shared environment. Each vehicle is assumed to have different and possibly unspecified tasks, but they cooperate to avoid collisions. We are interested in designing a scalable architecture capable of accommodating a very large and dynamically changing number of vehicles, guaranteeing their safety, the achievement of their goals, and security against potential adversaries. By properly distributing and revoking cryptographic keys we are able to protec…
Midground Object Detection in Real World Video Scenes,
2007
Traditional video scene analysis depends on accurate background modeling to identify salient foreground objects. However, in many important surveillance applications, saliency is defined by the appearance of a new non-ephemeral object that is between the foreground and background. This midground realm is defined by a temporal window following the object's appearance; but it also depends on adaptive background modeling to allow detection with scene variations (e.g., occlusion, small illumination changes). The human visual system is ill-suited for midground detection. For example, when surveying a busy airline terminal, it is difficult (but important) to detect an unattended bag which appears…
An Agent-based Service Network for Personal Mobile Devices
2006
We propose the Agent Network for Bluetooth Devices, a system that uses personal mobile devices as adaptive human-environment interfaces to supply people with ad hoc information and high-level services. The ANBD system operates with a hierarchical framework of service-providing nodes, dynamically composed and managed by mobile agents.
An Approach to Enhance Chatbot Semantic Power and Maintainability: Experiences within the FRASI Project
2012
The paper illustrates the implementation and semantic enhancement of a domain-oriented Question-Answering system based on a pattern-matching chat bot technology, developed within an industrial project, named FRASI. The main difficulty in building a KB for a chat bot is to handwrite all possible question-answer pairs that constitute the KB. The proposed approach simplifies the chat bot realization thanks to two solutions. The first one uses an ontology, which is exploited in a twofold manner: to construct dynamic answers as a result of an inference process about the domain, and to automatically populate, off-line, the chat bot KB with sentences that can be derived from the ontology, describi…
Towards a Smart Campus Through Participatory Sensing
2018
In recent years, the percentage of the population owning a smartphone has increased significantly. These devices provide users with more and more functions that make them real sensing platforms. Exploiting the capabilities offered by smartphones, users can collect data from the surrounding environment and share them with other entities in the network thanks to existing communication infrastructures, i.e., 3G/4G/5G or WiFi. In this work, we present a system based on participatory sensing paradigm using smartphones to collect and share local data in order to monitor make a campus 'smart'. In particular, our system infers the activities performed by users (e.g., students) in a campus in order …