Low-Cost Conversion of Single-Zone HVAC Systems to Multi-Zone Control Systems Using Low-Power Wireless Sensor Networks

This paper presents a novel approach to convert a conventional house air conditioning installation into a more efficient system that individually controls the temperature of each zone of the house through Wi-Fi technology. Each zone regulates the air flow depending on the detected temperature, providing energy savings and increasing the machine performance. Therefore, the first step was to examine the communication bus of the air conditioner and obtain the different signal codes. Thus, an alternative Controller module has been designed and developed to control and manage the requests on the communication bus (Bus–Wi-Fi gateway). A specific circuit has been designed to adapt the signal of the serial port of the Controller with the communication bus. For the acquisition of the temperature and humidity data in each zone, a Node module has been developed, which communicates with the Controller through the Wi-Fi interface using the Message Queuing Telemetry Transport (MQTT) protocol with Secure Sockets Layer / Transport Layer Security (SSL/TLS) certificates. It has been equipped with an LCD touch screen as a human-machine interface. The Controller and the Node modules have been developed with the ultra-low power consumption CC3200 microController of Texas Instruments and the code has been implemented under the TI-RTOS real-time operating system. An additional module based on the Raspberry Pi computer has been designed to create the Wi-Fi network and implement the required network functionalities. The developed system not only ensures that the temperature in each zone is the desired one, but also controls the fan velocity of the indoor unit and the opening area of the vent registers, which considerably improves the efficiency of the system. Compared with the single-zone system, the experiments carried out show energy savings between 75% and 94% when only one of the zones is selected, and 44% when the whole house is air-conditioned, in addition to considerably improving user comfort

Diseño de metodologías y herramientas para la estimación de los efectos de sitio y su aplicación en la evaluación de escenarios de daños debidos a terremotos

El objetivo de este proyecto era adquirir la experiencia, conocimientos y contactos con otros equipos de investigación necesarios para el desarrollo de metodologías y diseño de aplicaciones que ayuden a desarrollar las líneas de investigación en efectos de sitio y riesgo sísmico que el grupo está desarrollando. Esto permitirá obtener resultados específicos para diferentes entornos y favorecerá la petición conjunta con investigadores de Noruega, Alemania y posiblemente algún otro país europeo, de proyectos nacionales o europeos.Proyecto financiado por el Vicerrectorado de Investigación de la Universidad de Alicante (GRJ0512

Design and Implementation of a Wireless Sensor Network for Seismic Monitoring of Buildings

This article presents a new wireless seismic sensor network system, especially design for building monitoring. The designed prototype allows remote control, and remote and real-time monitoring of the recorded signals by any internet browser. The system is formed by several Nodes (based on the CC3200 microcontroller of Texas Instruments), which are in charge of digitizing the ambient vibrations registered by three-component seismic sensors and transmitting them to a central server. This server records all the received signals, but also allows their real-time visualization in several remote client browsers thanks to the JavaScript’s Node.js technology. The data transmission uses not only Wi-Fi technology, but also the existing network resources that nowadays can be found usually in any official or residential building (lowering deployment costs). A data synchronization scheme was also implemented to correct the time differences between the Nodes, but also the long-term drifts found in the internal clock of the microcontrollers (improving the quality of records). The completed system is a low-cost, open-hardware and open-software design. The prototype was tested in a real building, recording ambient vibrations in several floors and observing the differences due to the building structure.This study was funded by the European Union’s Horizon 2020 research and innovation program under grant agreement No 821046, the Ministerio de Economía, Industria y Competitividad through research project CGL2016-77688-R, by the Consellería de Participación, Transparencia, Cooperación y Calidad Democrática de la Generalitat Valenciana, and by Research Group VIGROB-116 (University of Alicante)

Design and Implementation of a Wireless Recorder System for Seismic Noise Array Measurements

In this work, a wireless data acquisition system for seismic noise array measurements is presented. The developed system is composed of a series of nodes and a central server arranged in a point-to-multipoint topology. The nodes consist of a CC3200 microcontroller, an analog-to-digital converter, and a low-noise conditioning circuit designed specifically to register seismic noise, and which is connected to the seismic sensor. As a server, a Raspberry Pi 4B has been used that will receive the samples from the nodes via Wi-Fi and will save them in files. It also incorporates a Web interface developed with JavaScript node.js technology that allows to configure the number of nodes as well as different options, to start and stop the records, and to view in real time the different signals received from the nodes. The system can be deployed anywhere since each of the nodes use independent batteries as a power supply. In addition, it is possible to operate the system remotely if internet connectivity is available. The prototype has been tested in four different locations in the Alicante province (southeast Spain), demonstrating its suitability for seismic noise array measurements

Methodology based on collaborative problem solving implemented in a high academic achievement group

[EN] The High Academic Achievement (ARA, by its acronym in Spanish) group began its course in the 2011/12 academic year to reinforce the potential of the most outstanding students since the beginning of their university studies. In order to improve the employability of this students, at least 50% of basic or compulsory credits of the degree are taught in English. In addition, a series of language training aids are provided, which also has advantages in obtaining Erasmus scholarships. The ARA group only offers 25 places each academic course. Being a small group, personalized teaching is enhanced while the schedule is compacted. In this contribution the methodology used in the subject of Signals and Systems of the Degree in Sound and Image in Telecommunication Engineering of the Alicante University (Spain) is presented. The methodology emphasizes the practical application of the subject and its direct applicability in real systems.Ferrando-Rocher, M.; Marini, S.; Galiana-Merino, J.; Carbajo, J. (2020). Methodology based on collaborative problem solving implemented in a high academic achievement group. En 6th International Conference on Higher Education Advances (HEAd'20). Editorial Universitat Politècnica de València. (30-05-2020):555-560. https://doi.org/10.4995/HEAd20.2020.11105OCS55556030-05-202

Perceptions, Uses, and Interpretations of Uncertainty in Current Weather Forecasts by Spanish Undergraduate Students

This quantitative study evaluates how 71 Spanish undergraduate students perceive and interpret the uncertainty inherent to deterministic forecasts. It is based on several questions that asked participants what they expect given a forecast presented under the deterministic paradigm for a specific lead time and a particular weather parameter. In this regard, both normal and extreme weather conditions were studied. Students’ responses to the temperature forecast as it is usually presented in the media expect an uncertainty range of ±1°–2°C. For wind speed, uncertainty shows a deviation of ±5–10 km h−1, and the uncertainty range assigned to the precipitation amount shows a deviation of ±30 mm from the specific value provided in a deterministic format. Participants perceive the minimum night temperatures as the least-biased parameter from the deterministic forecast, while the amount of rain is perceived as the most-biased one. In addition, participants were then asked about their probabilistic threshold for taking appropriate precautionary action under distinct decision-making scenarios of temperature, wind speed, and rain. Results indicate that participants have different probabilistic thresholds for taking protective action and that context and presentation influence forecast use. Participants were also asked about the meaning of the probability-of-precipitation (PoP) forecast. Around 40% of responses reformulated the default options, and around 20% selected the correct answer, following previous studies related to this research topic. As a general result, it has been found that participants infer uncertainty into deterministic forecasts, and they are mostly used to take action in the presence of decision-making scenarios. In contrast, more difficulties were found when interpreting probabilistic forecasts.This work has been funded by the Assistance Programme of University of Alicante “Programa de Redes-I3CE de calidad, innovación e investigación en docencia universitaria. Convocatoria 2019-20. Alicante: Instituto de Ciencias de la Educación (ICE) de la Universidad de Alicante. Ref: [4669].

On the calculation of smoothing kernels for seismic parameter spatial mapping: methodology and examples

Spatial mapping is one of the most useful methods to display information about the seismic parameters of a certain area. As in b-value time series, there is a certain arbitrariness regarding the function selected as smoothing kernel (which plays the same role as the window size in time series). We propose a new method for the calculation of the smoothing kernel as well as its parameters. Instead of using the spatial cell-event distance we study the distance between events (event-event distance) in order to calculate the smoothing function, as this distance distribution gives information about the event distribution and the seismic sources. We examine three different scenarios: two shallow seismicity settings and one deep seismicity catalog. The first one, Italy, allows calibration and showcasing of the method. The other two catalogs: the Lorca region (Spain) and Vrancea County (Romania) are examples of different function fits and data treatment. For these two scenarios, the prior to earthquake and after earthquake b-value maps depict tectonic stress changes related to the seismic settings (stress relief in Lorca and stress build-up zone shifting in Vrancea). This technique could enable operational earthquake forecasting (OEF) and tectonic source profiling given enough data in the time span considered.This research has been supported by the Horizon 2020 (TURNkey (grant no. 821046)) and the Ministerio de Ciencia e Innovación (grant no. PID2021-123135OB-C21)

Risk-targeted hazard maps for Spain

Many studies have demonstrated that the design of structures in a region through the uniform hazard principle does not guarantee a uniform collapse risk. Even in regions with similar Peak Ground Accelerations (PGAs) corresponding to the same mean return period, the seismic risk in terms of collapse probability will be significantly different mainly due to the shape of the hazard curves as well as uncertainties in structural capacities. In this paper, risk-targeted hazard mapping is being explored in peninsular Spain using a recently updated seismic hazard map. Since risk targeting involves multiple input parameters such as the model parameters of fragility curves, their variability was considered through their probability distribution as observed in reinforced concrete (RC) moment frame buildings, representing the most common building typology in Spain. The influence of the variation of these parameters on the risk results were investigated, and different assumptions for estimating the model parameters of fragility curves are illustrated. These assumptions were included in a fixed (generic) fragility curve or building-site-specific fragility curves. Different acceptable damage states (i.e., collapse and yielding) were considered concerning Spain’s seismicity level. Finally, the maps for risk-targeted design ground motions and risk coefficients are presented. It is outlined that the employment of risk-targeted analysis leads to the modifications for existing design ground motions due to the different shape of the hazard curves across Spain and considering the uncertainty of structural capacity. Moreover, it is found that using the building- and site-specific fragility curves could result in a more uniform seismic risk across the country.The study has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 821046, the Ministerio de Economía, Industria y Competitividad through research project CGL2016-77688-R, with the collaboration and funding provided by Elche and Alicante municipalities

Shallow S-Wave Velocity Structure in the Middle-Chelif Basin, Algeria, Using Ambient Vibration Single-Station and Array Measurements

In order to better assess the seismic hazard in the northern region of Algeria, the shear-wave velocity structure in the Middle-Chelif Basin is estimated using ambient vibration single-station and array measurements. The Middle-Chelif Basin is located in the central part of the Chelif Basin, the largest of the Neogene sedimentary basins in northern Algeria. This basin hosts the El-Asnam fault, one of the most important active faults in the Mediterranean area. In this seismically active region, most towns and villages are built on large unconsolidated sedimentary covers. Application of the horizontal-to-vertical spectral ratio (HVSR) technique at 164 sites, and frequency–wavenumber (F–K) analysis at 7 other sites, allowed for the estimation of the ground resonance frequencies, shear-wave velocity profiles, and sedimentary cover thicknesses. The electrical resistivity tomography method was used at some sites to further constrain the thickness of the superficial sedimentary layers. The soil resonance frequencies range from 0.75 Hz to 12 Hz and the maximum frequency peak amplitude is 6.2. The structure of the estimated shear-wave velocities is presented in some places as 2D profiles to help interpret the existing faults. The ambient vibration data allowed us to estimate the maximum depth in the Middle-Chelif Basin, which is 760 m near the city of El-Abadia.This study was funded by the Consellería de Participación, Transparencia, Cooperación y Calidad Democrática de la Generalitat Valenciana, and by Research Group VIGROB-116 (University of Alicante)

A Shear-Wave Velocity Model in the City of Oued-Fodda (Northern Algeria) from Rayleigh Wave Ellipticity Inversion

The city of Oued-Fodda is located in north-central Algeria on the margins of the Middle-Cheliff Basin. This region has suffered several destructive earthquakes. The strongest was the 1980 El-Asnam earthquake (Ms7.3), whose causative fault was located about 1 km north of the city of Oued-Fodda. Therefore, a good knowledge of the soil characteristics in this city may allow a better evaluation of the seismic risk and help to minimize damages in the future. With this objective, a detailed microzonation study of Oued-Fodda has been carried out in this study. For that, the horizontal-to-vertical spectral ratio (HVSR) method has been applied on 102 sites along the city, estimating the soil fundamental frequencies and their corresponding amplitudes. Besides, the Rayleigh wave ellipticity inversion has been accomplished in order to estimate the corresponding Vs profiles and provide two cross-sections of the geology under the city. In the central part of the city, high-frequency peaks are observed, between 12.5 and 15 Hz, which correspond to impedance contrasts at shallow depth (<20 m). In the surrounding plain, two clear peaks are identified in the ranges 1.8–3.5 Hz (fundamental frequencies) and 6.5–15 Hz (secondary peaks)