Unai Hernandez-Jayo

A Novel Cluster-Based Energy Efficient Routing in Wireless Sensor Networks

Recent development in electronics and wireless communications has enabled the improvement of low-power and low cost wireless sensors networks. Wireless Sensor Networks(WSNs) are a combination of autonomous devices transmitting locally gathered information to a so-called sink node by using multihop wireless routing. One of the most important challenges in WSNs is to design energy efficient routing mechanism to increase the network lifetime due to the limited energy capacity of the network nodes. Furthermore, hot spots in a WSNs emerge as locations under heavy traffic load. Nodes in such areas quickly drain energy resources, leading to disconnection in network services. Cluster based routing algorithms in WSNs have recently gained increased interest, and energy efficiency is of particular interest. A cluster head (CH) represents all nodes in the cluster and collects data values from them. To balance the energy consumption and the traffic load in the network, the CH should be rotated among all nodes and the cluster size should be carefully determined at different parts of the WSNs. In this paper, we proposed an cluster based energy efficient routing algorithm (CBER), CBER elects CH based on nodes near to the optimal cluster head distance and residual energy of the nodes. In WSNs energy is mostly consumed for transmission and reception, it is a non linear function of transmission range. In this paper, the optimal cluster head distance which links to optimal energy consumption is derived. In addition, residual energy is considered in the CH election in order to increase the network lifetime. Furthermore, the energy consumption of being a CH is equally spread among the cluster members. Performance results show CBER scheme reduces the end to end energy consumption and prolong the network lifetime of multi hop network compared to the well-known clustering algorithms LEACH and HEED.

LXI technologies for remote labs: an extension of the VISIR project

Several remote labs to support analog circuits are presented in this work. They are analyzed from the software and the hardware point of view. VISIR remote lab is one of these labs. After this analysis, a new VISIR remote lab approach is presented. This extension of the VISIR project is based on LXI technologies with the aim of becoming it in a remote lab easily interchangeable with other instruments. The addition of new components and experiments is also easier and cheaper.

Cluster-based MAC in VANETs for safety applications

Recently, we are witnessing increased interest in the research of Vehicular Ad-hoc Networks (VANETs). Traffic safety applications using VANETs aim to improve traffic safety in the road using messages which have to meet high reliability, low and predictable delay constraints. Moreover, due to characteristics of VANETs, such as high speed, unstable communication link, and network partitioning, information transfer becomes inevitably challenging. The effectiveness of traffic safety applications using VANETs depends up on the performance of medium access protocol (MAC). Vehicles using CSMA/CA (IEEE 802.11p) MAC algorithm the time to channel access increases randomly every time when the channel is sensed busy. The main challenge for the design of MAC protocol for VANETs is to achieve reliable delivery of messages within the time limit even when the density of vehicles varies rapidly in the network. Furthermore, MAC algorithms with good scalability, fairness, and predictable delay are needed to fulfill the requirements of traffic safety applications. Therefore, cluster-based MAC protocols that can avoid or limit channel contention, provide fairness to channel access, increases radio capacity by the spatial reuse of network resources and effectively control the topology of the network. However, due to the high mobility characteristics of VANETS, vehicles frequently join and leave clusters affects the stability of network. Furthermore, the stability become worse if the cluster heads (CH) elected are not stable. Therefore, maintaining cluster stability can increase performance of safety applications in VANETs. Finally, we propose two cluster based MAC protocols (D-CBM) based on contention based carrier sense multiple access (CSMA) and collision free time division multiple access (TDMA) in order to achieve high stability, low communication overhead and real time delivery of safety messages. Simulation results indicate the proposed protocols are able to achieve the above requirements. Furthermore, we analyze the performance of the proposed MAC design with SBCA protocol.

Cross-Layer Cluster-Based Energy-Efficient Protocol for Wireless Sensor Networks

Recent developments in electronics and wireless communications have enabled the improvement of low-power and low-cost wireless sensors networks (WSNs). One of the most important challenges in WSNs is to increase the network lifetime due to the limited energy capacity of the network nodes. Another major challenge in WSNs is the hot spots that emerge as locations under heavy traffic load. Nodes in such areas quickly drain energy resources, leading to disconnection in network services. In such an environment, cross-layer cluster-based energy-efficient algorithms (CCBE) can prolong the network lifetime and energy efficiency. CCBE is based on clustering the nodes to different hexagonal structures. A hexagonal cluster consists of cluster members (CMs) and a cluster head (CH). The CHs are selected from the CMs based on nodes near the optimal CH distance and the residual energy of the nodes. Additionally, the optimal CH distance that links to optimal energy consumption is derived. To balance the energy consumption and the traffic load in the network, the CHs are rotated among all CMs. In WSNs, energy is mostly consumed during transmission and reception. Transmission collisions can further decrease the energy efficiency. These collisions can be avoided by using a contention-free protocol during the transmission period. Additionally, the CH allocates slots to the CMs based on their residual energy to increase sleep time. Furthermore, the energy consumption of CH can be further reduced by data aggregation. In this paper, we propose a data aggregation level based on the residual energy of CH and a cost-aware decision scheme for the fusion of data. Performance results show that the CCBE scheme performs better in terms of network lifetime, energy consumption and throughput compared to low-energy adaptive clustering hierarchy (LEACH) and hybrid energy-efficient distributed clustering (HEED).

Spreading remote lab usage a system — A community — A Federation

Experiments have been at the heart of scientific development and education for centuries. From the outburst of Information and Communication Technologies, virtual and remote labs have added to hands-on labs a new conception of practical experience, especially in Science, Technology, Engineering and Mathematics education. This paper aims at describing the features of a remote lab named Virtual Instruments System in Reality, embedded in a community of practice and forming the spearhead of a federation of remote labs. More particularly, it discusses the advantages and disadvantages of remote labs over virtual labs as regards to scalability constraints and development and maintenance costs. Finally, it describes an actual implementation in an international community of practice of engineering schools forming the embryo of a first world wide federation of Virtual Instruments System in Reality nodes, under the framework of a project funded by the Erasmus+ Program.

A multi-objective evolutionary algorithm for the tuning of fuzzy rule bases for uncoordinated intersections in autonomous driving

This paper focuses on the application of Multi-Objective Evolutionary Algorithms (MOEAs) to develop a Fuzzy Rule-Based System (FRBS) dedicated to manage the speed of an autonomous vehicle in an intersection scenario.Compared to other intersection scenarios, the main point here is that the autonomous vehicle is approaching an intersection that is being crossed by a row of manual vehicles those are not paying any attention to the presence of the autonomous vehicle, thus making coordination impossible. In this case, the autonomous vehicle bears sole responsibility for adapting its speed to the state of the other vehicles, with the aim of completing the maneuver safely and efficiently.The specific conditions of this problem make it complex because of the large time requirements needed to consider multiple criteria (which enlarge the solution search space) and the long computation time required in each evaluation. In addition, the large number of variables involved increases the complexity of the scenario.In this paper, a MOEA is proposed to obtain a more compact and efficient FRBS. The proposal is based on the well-known Strength Pareto Evolutionary Algorithm 2 (SPEA2) technique, but uses different mechanisms for guiding the search towards the desired Pareto zone. The MOEA uses specific operators to deal with the problem, to inherit fitness values from one generation to the next, thus arranging that it is only necessary to execute one scenario per generation to obtain an FRBS that works fine in many situations. In addition, the most important rules are identified in each FRBS, with the aim of realizing balanced crossovers.

Empirical Analysis of the Use of the VISIR Remote Lab in Teaching Analog Electronics

Remote laboratories give students the opportunity of experimenting in STEM by using the Internet to control and measure an experimental setting. Remote laboratories are increasingly used in the classroom to complement, or substitute for, hands-on laboratories, so it is important to know its learning value. While many authors approach this question through qualitative analyses, this paper reports a replicated quantitative study that evaluates the teaching performance of one of these resources, the virtual instrument systems in reality (VISIR) remote laboratory. VISIR, described here, is the most popular remote laboratory for basic analog electronics. This paper hypothesizes that use of a remote laboratory has a positive effect on students’ learning process. This report analyzes the effect of the use of VISIR in five different groups of students from two different academic years (2013–2014 and 2014–2015), with three teachers and at two educational levels. The empirical experience focuses on Ohm’s Law. The results obtained are reported using a pretest and post-test design. The tests were carefully designed and analyzed, and their reliability and validity were assessed. The analysis of knowledge test question results shows that the post-test scores are higher that the pretest. The difference is significant according to Wilcoxon test (

Intelligent Transport Systems: Technologies and Applications

{p} <0.001

Design of a Mobile Low-Cost Sensor Network Using Urban Buses for Real-Time Ubiquitous Noise Monitoring

), and produces a Cohen effect size of 1.0. The VISIR remote laboratory’s positive effect on students’ learning processes indicates that remote laboratories can produce a positive effect in students’ learning if an appropriate activity is used.

V-Alert: Description and Validation of a Vulnerable Road User Alert System in the Framework of a Smart City

The book provides a systematicoverview of Intelligent Transportation Systems (ITS). First, it includes aninsight into thereference architectures developed within the main EU research projects. Then, it delves into each of the layers of such architectures, from physical to application layer, describing the technological issues which are being currently faced by some of the most important ITS research groups. The bookconcludes with some end user services and applications deployed by industrial partners. This book is a well-balanced combination of academic contributions and industrial applications in the field of Intelligent Transportation Systems. The most representative technologies and research results achieved by some of the most relevant research groups working on ITS,collated to show the chances of generating industrial solutions to be deployed in real transportation environments.