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Lara-Cueva R.A.,Ad Energy | Gordillo R.,Ad Energy | Valencia L.,Ad Energy | Benitez D.S.,San Francisco de Quito University
IEEE Sensors Journal | Year: 2017

This paper presents a study in order to identify the value range of the main parameters within carrier sense multiple access (CSMA) defined in IEEE 802.15.4 that guarantees a satisfactory wireless sensor network (WSN) performance for a volcano monitoring application. Moreover, this study performs the comparison among several test-beds in outdoor scenarios with the purpose of distinguishing the optimal number of nodes for each gateway according the main constraints given by an existing sensor network for real-time (RT) volcano monitoring system such as sampling time, packet loss, and delay. We used a mathematical model that works with Markovian techniques and involves some parameters of CSMA mechanism within the model, such as the minimum value of the backoff exponent (BEmin), the contention window length (W), and the number of slots (L). We obtained the approximate values of these parameters by the interpolation of the normalized throughput curves from the deployment, and thus, we could obtain a mathematical model with the specifications required for the RT volcano monitoring. After validating the model with test-bed outdoor deployments we found that BEmin, W and L are key factors for determining the performance of a WSN, these parameters guarantee the range in which the WSN works according to the constraints imposed for this particular volcano monitoring application. © 2016 IEEE.

Agency: European Commission | Branch: H2020 | Program: IA | Phase: EEB-03-2016 | Award Amount: 7.93M | Year: 2016

Heat4Cool proposes an innovative, efficient and cost-effective solution to optimize the integration of a set of rehabilitation systems in order to meet the net-zero energy standards. The project develops, integrates and demonstrates an easy to install and highly energy efficient solution for building retrofitting that begins from the Heat4Cool advanced decision-making tool (which addresses the building and district characteristics) and leads to the optimal solution combining (1) gas and solar thermally driven adsorption heat pumps, which permits the full integration with existing natural gas boilers to ensure efficient use of current equipment , (2) solar PV assisted DC powered heat pump connected to an advanced modular PCM heat and cold storage system, and (3) energy recovery from sewage water with high performance heat exchangers. This retrofitting solution together with a closer interaction between building monitoring, demand/respond supply match, weather forecast and HVAC activation/control through a Self-Correcting Intelligent Building Energy Management Systems (SCI-BEMS) will save at least 10% of energy consumption. The project will implement four benchmark retrofitting projects in four different European climates to achieve a reduction of at least 20% in energy consumption in a technically, socially, and financially feasible manner and demonstrate a return on investment of 8 years. The Heat4Cool consortium will ensure the maximum replication potential of the Heat4Cool solution by a continuous monitoring of technical and economic barriers during the development and validation phases in order to present the building owners and investors with clear energy and economic evidence of the value of implementing Heat4Cool solution. A detailed business plan will be developed in the beginning of the project to strengthen the exploitation plan of the retrofitting package and set the basis for a massive replication of the demonstrated concept across Europe.

Agency: European Commission | Branch: H2020 | Program: RIA | Phase: EE-11-2014 | Award Amount: 1.78M | Year: 2015

Tertiary sector buildings sector consume a sizeable proportion of EU total energy consumption and the majority of consumption is directly attributed to the operational phase of the building life-cycle. Occupant behaviour is a major cause of this consumption. OrbEEt proposes an ICT-based framework to induce behaviour change toward energy efficiency by transforming energy measurements into personalized feedback delivered through engaging user interfaces. To achieve this challenge, OrbEEt foresees dynamic, spatially fine-grained extensions of building-level Operational Rating methodologies and Display Energy Certificates to provide a detailed view of energy use in office spaces, business processes and organizational entities rather than entire buildings. The fusion of information from Building Information Models, Business Process Models and real-time energy use measurement via a comprehensive ICT cloud service - the Systemic Enterprise Operational Rating framework - will enable energy use tracking and will establish direct accountability of people, processes and spaces toward overall consumption. Exposing the direct influence of occupant behaviour on energy use enables the design and successful deployment of behavioural change campaigns in public organization buildings. OrbEEt proposes interventions appealing to intrinsic/extrinsic human motivators through intra-organization social competitions and organization-wide social collaboration endeavours. The OrbEEt framework and behavioural change interventions will undergo real-life pilot validation in four EU public buildings that provide the business, cultural and geographical diversity for demonstration of result effectiveness and transferability. Finally, the OrbEEt consortium will use a User Driven Innovation Approach throughout its development, deployment and validation of phases to leverage and actively support Open Innovation and the EU Cleanweb/start-up community toward further exploitation of its outcomes.

Ltaief O.O.,Ad Energy | Siffert S.,ULCO | Fourmentin S.,ULCO | Benzina M.,Ad Energy
Comptes Rendus Chimie | Year: 2015

In this study, a faujasite type zeolite synthesized from cheap local Tunisian illitic clay and having a hierarchical porosity was used for adsorption of heavy metals. The adsorption behavior of the FAU with respect to Cu (II), Cr (III) and Co (II) has been investigated using batch experiments. The removal efficiency was determined at different contact times, initial metal concentrations, temperatures, pHs, and adsorbent amounts. Both Langmuir and Freundlich isotherms fit well with the equilibrium data. Kinetic studies showed that the adsorption followed a pseudo-second-order model. The observed selectivity was determined as follow: Cu (II). >. Co (II). >. Cr (III). Une zéolite de type faujasite ayant une porosité hiérarchisée a été synthétisée à partir d'une argile tunisienne. Les capacités d'adsorption de cette zéolite ont été évaluées vis-à-vis de la rétention de métaux lourds: Cu (II), Cr (III) et Co (II). L'influence de divers paramètres tels que le temps, la concentration, la température, le pH et la quantité d'adsorbant a été étudiée. Les résultats obtenus ont montré que les modèles de Langmuir et Freundlich décrivaient bien l'adsorption des métaux étudiés et que l'adsorption suivait un modèle cinétique du deuxième ordre. La sélectivité observée suit l'ordre: Cu (II). >. Co (II). >. Cr (III). © 2015 Académie des sciences.

Lara-Cueva R.,Ad Energy | Olmedo G.,Ad Energy | Calvopina K.,Ad Energy
CHILECON 2015 - 2015 IEEE Chilean Conference on Electrical, Electronics Engineering, Information and Communication Technologies, Proceedings of IEEE Chilecon 2015 | Year: 2015

This article describes the performance evaluation of a new wireless TCP algorithm in real environments, in order to identify the advantages and disadvantages of its operation. We evaluate the proposed wireless TCP algorithm with respect to generic TCP, considering an intrusive technique by using traffic injection. These tests were performed over point-to-point WiFi and WiMAX links in out-door and in-door environments. The proposed amendment for wireless TCP was incorporated in a virtual machine under Linux operating system, and using D-ITG tool for the traffic injections. We assess the performance of the proposed algorithm in terms of the main parameters of Quality of Service (QoS) as throughput, delay, and jitter. Our primary results demonstrate that our new proposal of the TCP algorithm presents better results in comparison with the generic TCP referred to all terms of QoS in wireless environments. © 2015 IEEE.

Zhang L.Y.,University of Oxford | He L.,University of Oxford | Stuer H.,Ad Energy
Proceedings of the ASME Turbo Expo | Year: 2012

The rotating instability phenomenon in a last stage of steam turbines at low mass flow conditions has been previously identified experimentally. Recently, the rotating instability has also been numerically studied in a whole annulus domain on 2D blade sections. In the present work, 3D simulations of unsteady flows are carried out on two model steam turbines over a range of mass flow conditions. The pressure-ratio volume-flow characteristics in rotor row tip region under different flow conditions are well captured in the computations in comparison with the experiment. The effect of blade scaling is examined to identify the influence of changing blade counts for a circumferential domain reduction, showing relatively small effects on the overall performance characteristics. The present 3D unsteady solutions on a reduced multi-passage domain have been able to predict a rotating instability in the rotor blade tip region, in accord with the corresponding experiment. Further Fourier analysis is carried out to examine the frequency pattern and spatial modal features. The 3D flow behavior is highlighted by comparison between the 3D and 2D calculations. The present results seem to suggest that the rotating instability onset in the rotor tip region is largely independent of the large scale flow separation in the downstream diffusor. Copyright © 2012 by ASME.

Lara-Cueva R.,Ad Energy | Benitez D.,San Francisco de Quito University | Fernandez C.,Ad Energy | Morales C.,Ad Energy
Proceedings - 2015 Asia-Pacific Conference on Computer-Aided System Engineering, APCASE 2015 | Year: 2015

Usage of wireless networks is rising in popularity. In this setting different kinds of networks for indoor environments, such as Ad-Hoc, IEEE 802.11b (Wi-Fi) and Wireless Distribution System (WDS) has been developed. In this paper, an analysis of Quality of Service (QoS) has been made for each network in order to verify the values of bit rate, delay, jitter and packet loss. For performance comparison of these networks, injection of UDP traffic was accomplished by means of the Distributed Internet Traffic Generator (D-ITG). Distance and number of obstacles were varied in several deployed network scenarios. In each scenario, QoS parameters were measured and efficiency was estimated. According to results, WDS networks have better performance which has 30% more efficiency in long distance communication than Ad-Hoc and 802.11 networks. © 2015 IEEE.

Lara-Cueva R.,Ad Energy | Carrera E.V.,Ad Energy | Morejon J.F.,Ad Energy | Benitez D.,San Francisco de Quito University
2016 IEEE Colombian Conference on Communications and Computing, COLCOM 2016 - Conference Proceedings | Year: 2016

The correct classification of several types of volcanic events can be used to determine the intrinsic behavior of a volcano. This information could be useful to provide an early alarm in the case of imminent volcanic activity. Therefore, finding an efficient algorithm capable of identifying seismic activity can be beneficial for this purpose. In such sense, this work evaluates several machine learning techniques, that have been previously applied to classify seismic events, taking into account quality and performance parameters. In order to test the algorithms, a seismic database from the Cotopaxi volcano in Ecuador was used. This database was collected by the Geophysical Institute at Escuela Politécnica Nacional between January and June of 2010. The analysis was focused in two major types of seismic events: long period and volcano tectonic. For each event, 79 key features in time and frequency domain were extracted. These features were used to train 3 well known classifiers: k-nearest neighbors, decision trees and neural networks. Finally, a feature selection technique was employed to find those features with greater impact improving the classifier performance. Our approach allow us to reach an accuracy of 98% by identifying 3 main features and using the k-NN classifier. © 2016 IEEE.

Lara-Cueva R.A.,Ad Energy | Almeida D.,Ad Energy | Benitez D.,San Francisco de Quito University
2016 IEEE Colombian Conference on Communications and Computing, COLCOM 2016 - Conference Proceedings | Year: 2016

This paper describes the methodology used to find a new semi-empirical propagation model based on received power measurements around a University Campus. The proposed model is then compared with other well known propagation models to determine its performance in the working frequency band from 5.725 to 5.85 GHz. Results indicate that the error obtained with the proposed model is lower than 5% when compared with actual measurements. © 2016 IEEE.

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