In this work, we propose a new Predictive-based Mobile Target Tracking Algorithm for Wireless Multimedia Sensor Networks called PMT2. Resource management being a critical feature of this kind of networks, the main aim of PMT2is to handle the trade-off between the accuracy of the tracking and the energy conservation. Prediction approach seems to be the best candidate to reach this objective. For this purpose, we introduce an enhanced version of the Extended Kalman Filter combined with a change detection mechanism named CuSum for Cumulative Summary. We also propose a deployment strategy to improve the efficiency of the tracking algorithm. Using simulations, we show the performances of the proposed coupled mechanism in the trajectory prediction and in the reactivity to abrupt direction changes. Moreover, we perform a comparative study between PMT2and existing works: 1) BASIC where all the Cameras Sensors are always in active mode; 2) OCNS for Optimal Camera Node Selection, a cluster-based solution with a probabilistic sensor selection; 3) PTA, another predictive solution based on standard Kalman Filter. The obtained results illustrate that PMT2improves the quality of tracking by up to 35% compared to existing works, while reducing energy consumption by up to 55%.

As the Internet of Things (IoT) grows in interest from both research and industrial parts, the lack of standard solutions to quickly and easily build and install IoT applications becomes a topic of high interest. In this paper, we introduce a language called SALT (Simple Application Logic description using Transducers) that allows describing and deploying the distributed logic needed in order to fulfil a complete desired application. This language aims at giving extended functionalities by filling the gap between the logical capabilities offered by services orchestration and the closeness efficiency of services choreography. SALT is interpreted by a virtual machine running on devices that introduces an abstraction layer in order to simplify access to hardware capabilities. SALT implements several mechanisms to comply with organisation issues presented in the Services Oriented Computing realm dealing with Services interactions, adapted to the specific constraints of the IoT. This work details SALT's concepts, formalism and implementation.

Wireless Sensor and Actuator Networks (WSAN) and permanent connections to the Internet converge to be an emerging and promising field: Machine-To-Machine (M2M) services. To take advantages of this new field, hardware and software infrastructure compliance must be verified. Services expected by M2M alter the organization of WSAN. The software design in this area can be divided into two main categories: a centralized approach (Orchestration) where a monolithic application collects data and sends orders, and a distributed approach (Choreography) in which nodes offer and use services in a collaborative way. In this paper, we study the impact of these two architectures over WSAN. First, a mathematical analysis shows the improvement offered by choreography, thanks to the use of shorter paths between nodes. Then, an application experiments these two architectural designs to measure the impact on a real testbed. Both the theoretical mathematical analysis and the real platform experiment gives better results for the Choreography in terms of network reliability and path length. Our work quantifies the benefits obtained and provides histograms and numerical results.

It has been analytically and empirically proved that Network Coding can significantly enhance wireless communications in terms of achievable throughput, data delivery and delay. While research in Network Coding has mainly ad dressed the problem of coding efficiency, buffer optimization and queuing, little attention has been paid to what we define as coding reliability, i.e., the ability for nodes to encode packets efficiently enough, so that a maximum number of its destinations can extract innovative data whatever the medium conditions can be. In this work, we investigate this concept in Wire less Sensor Networks (WSN) then we present Re-CoZi, a pack et transport mechanism which enables robust XOR Coding for WSN using echo-feedback packet reception and decoding acknowledgement. Our performance analysis shows that Re CoZi keeps the added value of NC in terms of bandwidth utilization and delay, while providing a more reliable coding.

We propose WSC an event-centric data-dissemination scheme for event-centric wireless sensor networks (EC-WSN) based on a distributed network coding scheme. Nodes in this solution, do not only forward messages, but also perform linear random information coding in order to increase the throughput of the network, to reduce the number of transmissions, the end-to-end delay, and thus to increase the WSN lifetime, which is one of the key-issues in sensor networks architecture design.

Numerous approaches based on metrics, token sequence pattern-matching, abstract syntax tree (AST) or program dependency graph (PDG) analysis have already been proposed to highlight similarities in source code: in this paper we present a simple and scalable architecture based on AST fingerprinting. Thanks to a study of several hashing strategies reducing false-positive collisions, we propose a framework that efficiently indexes AST representations in a database, that quickly detects exact (w.r.t source code abstraction) clone clusters and that easily retrieves their corresponding ASTs. Our aim is to allow further processing of neighboring exact matches in order to identify the larger approximate matches, dealing with the common modification patterns seen in the intra-project copy-pastes and in the plagiarism cases.

This paper presents a Java framework based on separation of concerns and code generation concepts that facilitates development of concurrency and I/O in servers. In this approach, the application is modeled by a graph whose vertices correspond to units of treatment connected by channels. It allows to build all kind of servers: multithreaded, single-process event-driven, staged event driven architecture, etc. without modification of the functional part. This architecture also permits to extend very easily an application, adding vertices and edges to the graph. The aim of our development tool is to improve programmer productivity and portability, decreasing development time, and reducing bugs or deadlock problems.

Controlling node mobility to improve communication performance is a capability that the ad hoc networking community begins to investigate. In this paper, we propose to use this possibility to ensure communication in a sparse wireless ad hoc network whose elements are mobile robots. In such a network, the elements are usually disconnected and thus, movements of robots are used to asynchronously forward messages. To communicate efficiently, we propose a controlled scheduling of the movements together with a routing algorithm. We prove that the scheduling is deadlock free and that it insures communication between any pair of robots. Then, the scheduling is enhanced and modified in order to support fault tolerance. We also describe some implementations showing the usability of our approach.

The article addresses the formal specification, design and implementation of the behavioral component of graphical user interfaces. The complex sequences of visual events and actions that constitute dialogs are specified by means of modular, communicating grammars called VEG (Visual Event Grammars), which extend traditional BNF grammars to make them more convenient to model dialogs.A VEG specification is independent of the actual layout of the GUI, but it can easily be integrated with various layout design toolkits. Moreover, a VEG specification may be verified with the model checker SPIN, in order to test consistency and correctness, to detect deadlocks and unreachable states, and also to generate test cases for validation purposes.Efficient code is automatically generated by the VEG toolkit, based on compiler technology. Realistic applications have been specified, verified and implemented, like a Notepad-style editor, a graph construction library and a large real application to medical software. It is also argued that VEG can be used to specify and test voice interfaces and multimodal dialogs. The major contribution of our work is blending together a set of features coming from GUI design, compilers, software engineering and formal verification. Even though we do not claim novelty in each of the techniques adopted for VEG, they have been united into a toolkit supporting all GUI design phases, that is, specification, design, verification and validation, linking to applications and coding.

In Java, method implementations are chosen at runtime by late-binding with respect to the runtime class of just the receiver argument. However, in order to simplify many programming designs, late-binding with respect to the dynamic type of all arguments is sometimes desirable. This behavior, usually provided by multimethods, is known as multipolymorphism. This work presents a new multimethod implementation based on the standard Java reflection mechanism. Provided as a package, it does not require any language extension or any virtual machine modification. The design issues of this reflective implementation are presented together with a new and simple multimethod dispatch algorithm that efficiently supports class loading at runtime. This implementation provides a practicable and fully portable multimethod solution.

The paper addresses the formal specification, design and implementation of the behavioral component of graphical user interfaces. Dialogs are specified by means of modular, communicating grammars called VEG (Visual Event Grammars), which extend traditional BNF grammars to make the modeling of dialogs more convenient. A VEG specification is independent of the actual layout of the GUI, but it can be easily integrated with various layout design toolkits. The specification may be verified with the model checker Spin, in order to test consistency and correctness, to detect deadlocks and unreachable states, and also to generate test cases for validation purposes. Efficient code is automatically generated by the VEG toolkit, based on compiler technology. Realistic applications have been specified, verified and implemented, like a Notepad-style editor, a graph construction library and a large real application to medical software. The complete VEG toolkit is going to be available soon as free software.