Self-healing topology discovery protocol for software defined networks

“© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. http://ieeexplore.ieee.org/document/8319433/”This letter presents the design of a self-healing protocol for automatic discovery and maintenance of the network topology in Software Defined Networks (SDN). The proposed protocol integrates two enhanced features (i.e. layer 2 topology discovery and autonomic fault recovery) in a unified mechanism. This novel approach is validated through simulation experiments using OMNET++. Obtained results show that our protocol discovers and recovers the control topology efficiently in terms of time and message load over a wide range of generated networks.Peer ReviewedPostprint (author's final draft

Energy-aware routing in multiple domains software defined networks

The growing energy consumption of communication networks has attracted the attention of the networking researchers in the last decade. In this context, the new architecture of Software-Defined Networks (SDN) allows a flexible programmability, suitable for the power-consumption optimization problem. In this paper we address the issue of designing a novel distributed routing algorithm that optimizes the power consumption in large scale SDN with multiple domains. The solution proposed, called DEAR (Distributed Energy- Aware Routing), tackles the problem of minimizing the number of links that can be used to satisfy a given data traffic demand under performance constraints such as control traffic delay and link utilization. To this end, we present a complete formulation of the optimization problem that considers routing requirements for control and data plane communications. Simulation results confirm that the proposed solution enables the achievement of significant energy savings.Peer ReviewedPostprint (published version

Discovering the network topology: an efficient approach for SDN

Network topology is a physical description of the overall resources in the network. Collecting this information using efficient mechanisms becomes a critical task for important network functions such as routing, network management, quality of service (QoS), among many others. Recent technologies like Software-Defined Networks (SDN) have emerged as promising approaches for managing the next generation networks. In order to ensure a proficient topology discovery service in SDN, we propose a simple agents-based mechanism. This mechanism improves the overall efficiency of the topology discovery process. In this paper, an algorithm for a novel Topology Discovery Protocol (SD-TDP) is described. This protocol will be implemented in each switch through a software agent. Thus, this approach will provide a distributed solution to solve the problem of network topology discovery in a more simple and efficient way.Peer ReviewedPostprint (published version

Arabidopsis thaliana is able to sense tomato Systemin promoting defense against fungal pathogens

Pòster presentat al Symposium on Small Molecules in Plant Research: Chemistry and Biology Come Together (Valencia, Spain, 10-11 December 2019).Systemin is a small tomato peptide that regulates the plant response against herbivores and pathogenic fungi. It is released from a larger precursor upon wounding or pathogen attack and binds to a membrane receptor of the adjacent cell inducing a cascade of plant defences, including JA-related responses, that lead to the accumulation of protease inhibitors in local and systemic tissue. Although the tomato Systemin has been the focus of many recent studies, very little is known about the perception and function of Systemin in heterologous species

Determination of the Insulation Solution that Leads to Lower CO2 Emissions during the Construction Phase of a Building

The characteristics of the envelope of a building determine, together with other factors, its consumption of energy. Additionally, the climate zone and insulation material may vary the minimum insulation thickness of walls and roofs, making it different, according to cooling down or warming up the home. Spanish legislation establishes different maximum values for energy demand according to different climate area both for heating and for cooling. This paper presents the results of a study that determines the influence of many variables as the climate zone or the orientation, among others, in the optimization of thickness insulation in residential homes in Spain to reduce the CO2 emissions embodied. To do that, 12 representative cities in Spain corresponding to different climate zones, four orientations, two constructive solutions, and four different configurations of the same house have been combined, for three different hypotheses and four insulation materials, resulting in 4608 cases of study. The results show that, under equal conditions on energy demand, the optimal insulation requirements are determined by heating necessities more than by cooling ones. In addition, a higher insulation thickness need does not necessarily mean more CO2 emissions, since it can be compensated with a lower Global Warming Potential characterization factor that is associated to the insulation material. The findings of this study can serve to designers and architects to establish the better combination of the variables that are involved in order to minimize the CO2 emissions embodied during the construction phase of a building, making it more energy efficient

Quantifying Functional Reuse from Object Oriented Requirements Specifications

Software reuse is essential in improving efficiency and productivity in the software development process. This paper analyses reuse within requirements engineering phase by taking and adapting a standard functional size measurement method, COSMIC FFP. Our proposal attempts to quantify reusability from Object Oriented requirements specifications by identifying potential primitives with a high level of reusability and applying a reuse indicator. These requirements are specified using OO-Method, an automatic software production method based on transformation models. We illustrate the application of our proposal in a Car Rental real system

Degradation diagnostics of lithium-ion batteries for automotive applications

Motivated by political, social and economic factors, automotive original equipment manufacturers have adopted vehicle electrification as a technology to either reduce or eliminate tailpipe emissions. However, the design and development of Battery Electric Vehicles (BEVs) are facing significant challenges to achieving full market penetration. Some of these challenges are to ensure specific battery performance, range, safety, charging time and lifetime. Battery degradation affects each of these factors negatively. To mitigate this negative impact, researchers agree that battery degradation needs to be better understood. For this, it is essential to develop non-invasive battery health diagnostic techniques that can be applied in real-world operating conditions. This Innovation Report presents the findings from an International Engineering Doctorate (EngD (Int.)). This Innovation Report investigates factors influencing the degradation of Lithium-ion Batteries (LIB) in BEV applications. The contribution of this research is to provide the underpinning knowledge that allows manufacturers to improve the durability and performance of Electric Vehicle battery assemblies concerning degradation. This contribution has been achieved through four related studies within two primary areas of investigation. Firstly, the research focuses on evaluating Cell-to-Cell Variabilities (CtCV) in LIB packs in Study 1 and their implications for the monitoring of the State of Health (SoH) in Study 2. Study 1 proposes a systematic procedure to quantify the amount and the origin of CtCV in battery packs. Study 2 quantifies CtCV experimentally with respect to SoH for a scenario equivalent to a typical BEV life (10 years) or customer mileage (100,000 miles). Further, Study 2 suggests a non-invasive methodology to monitor SoH in a vehicle. These results can be employed by academics and engineers to quantify battery degradation in imbalance scenarios. The second avenue of investigation was to improve the current SoH definition employed in the automotive industry. After conducting a critical and extensive review of the most pertinent literature in Study 3, Study 4 suggests a step-by-step methodology to quantify the most pertinent degradation modes. This non-invasive diagnosis methodology can be applied in the context of on-board and on-board vehicle applications. The application of this methodology can be further used by academia and industry to improve lifetime control strategies and future battery designs. In conclusion, the impact of this thesis is to define diagnosis techniques that can be further employed by engineers to reduce the negative consequences of battery degradation into battery performance, autonomy and lifetime

A multi-objective routing strategy for QoS and energy awareness in software-defined networks

“© © 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. http://ieeexplore.ieee.org/document/8013750/”Energy consumption is a key concern in the deployment and operation of current data networks, for which Software-Defined Networks (SDN) have become a promising alternative. Although several works have been proposed to improve the energy efficiency, these techniques may lead to performance degradations when QoS requirements are neglected. Inspired by this problem, this letter introduces a new routing strategy, jointly considering QoS requirements and energy awareness in SDN with in-band control traffic. To that end, we present a complete formulation of the optimization problem and implement a Multi- Objective Evolutionary Algorithm. Simulation results validate the performance improvement on critical network parameters.Peer ReviewedPostprint (published version

Estudio de la variación del pensamiento divergente en física según la edad de los alumnos

Divergent Thinking, DT, is a mental mechanism which takes part in the process of solving problems having more than one valid solution. It is considered as a fundamental aspect of creativity. In our research about DT in Physics, we intended to present a new method, using the Guilford's E.I. tridimensional model as a referential framework, since we are convinced that it is crucially important to have an educational system which emphasizes creativity and the skills of the future scientist so that he/she will be able to face any challenging situation. In this paper we study the DT variation with age in Physics, and we have found out that younger students are likely to show better progress