A smart campus is an intelligent infrastructure where smart sensors and actuators collaborate to collect information and interact with the machines, tools, and users of a university campus. As in a smart city, a smart campus represents a challenging scenario for Internet of Things (IoT) networks, especially in terms of cost, coverage, availability, latency, power consumption, and scalability. The technologies employed so far to cope with such a scenario are not yet able to manage simultaneously all the previously mentioned demanding requirements. Nevertheless, recent paradigms such as fog computing, which extends cloud computing to the edge of a network, make possible low-latency and location-aware IoT applications. Moreover, technologies such as Low-Power Wide-Area Networks (LPWANs) have emerged as a promising solution to provide low-cost and low-power consumption connectivity to nodes spread throughout a wide area. Specifically, the Long-Range Wide-Area Network (LoRaWAN) standard is one of the most recent developments, receiving attention both from industry and academia. In this article, the use of a LoRaWAN fog computing-based architecture is proposed for providing connectivity to IoT nodes deployed in a campus of the University of A Coruna (UDC), Spain. To validate the proposed system, the smart campus has been recreated realistically through an in-house developed 3D Ray-Launching radio-planning simulator that is able to take into consideration even small details, such as traffic lights, vehicles, people, buildings, urban furniture, or vegetation. The developed tool can provide accurate radio propagation estimations within the smart campus scenario in terms of coverage, capacity, and energy efficiency of the network. The results obtained with the planning simulator can then be compared with empirical measurements to assess the operating conditions and the system accuracy. Specifically, this article presents experiments that show the accurate results obtained by the planning simulator in the largest scenario ever built for it (a campus that covers an area of 26,000 m 2 ), which are corroborated with empirical measurements. Then, how the tool can be used to design the deployment of LoRaWAN infrastructure for three smart campus outdoor applications is explained: a mobility pattern detection system, a smart irrigation solution, and a smart traffic-monitoring deployment. Consequently, the presented results provide guidelines to smart campus designers and developers, and for easing LoRaWAN network deployment and research in other smart campuses and large environments such as smart cities.

Design and Experimental Validation of a LoRaWAN Fog Computing Based Architecture for IoT Enabled Smart Campus Applications

This work was supported in part by the 2017 Predoctoral Research Grant through the Xunta de Galicia and the Research Projects funded by the Ministerio de Ciencia, Innovacion y Universidades, Gobierno de Espana through Ministerio de Ciencia, Innovacion y Universidades (MCIU)/Agencia Estatal de Investigacion (AEI)/Fondo Europeo de Desarrollo Regional (FEDER)/Union Europea (UE) under Grant TEC2017-85529-C03-3R and Grant RTI2018-095499-B-C31, and in part by the European Union’s Horizon 2020 Research and Innovation Program (Stardust-Holistic and Integrated Urban Model for Smart Cities) under Grant N◦774094.

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Aggregator to electric vehicle LoRaWAN based communication analysis in vehicle-to-grid systems in smart cities

Transportation system is experiencing steady growth, with the aim of providing more efficient, reliable, and comfortable services, in the framework of intelligent transportation systems. Moreover, context aware environments are one of the main drivers in the achievement of smart cities and smart regions. In this paper, wireless sensor networks (WSNs) embedded in urban transportation systems will be analyzed in terms of impact on wireless channel behavior and system performance. An in-house developed 3-D ray launching tool, with the inclusion of in-house human body model as well as with the study of interference levels is employed. Wireless channel estimations indicate an initial infrastructure node density in the order of 1node/150m2 to 1node/500m2 as a function of the employed transceivers. A practical solution has been implemented, combining an Android-based application and a system level architecture over the WSN for urban train transportation environmental monitoring, providing interaction between users and the environment, with the aid of a combined WSN/WLAN platform as well as an implemented software architecture, scalable in terms of user density and future needs.

Design and Implementation of Context Aware Applications With Wireless Sensor Network Support in Urban Train Transportation Environments

Simulation techniques based on deterministic methods such as ray tracing and ray launching are widely used to perform radioplanning tasks. However, the quality of the simulations depends on the number of rays and the angular resolution. The computational cost of these simulations in high definition prevents their use in complex environment, and their low-definition counterparts are used instead. In this letter, we propose a technique based on collaborative filtering to lessen the poor-quality problems of low-definition simulations. We show that our approach obtains results very similar to those of high definition in much less time. Also, we compare our approach to other well-known techniques and show that it performs better in terms of accuracy and precision. The use of combined deterministic/collaborative filtering techniques allows the estimation of radioplanning tasks in large, complex scenarios with a potentially large amount of transceivers.

Optimized Wireless Channel Characterization in Large Complex Environments by Hybrid Ray Launching-Collaborative Filtering Approach

A novel and efficient deterministic approach to model radiowave propagation channels in complex indoor environments, improving prediction accuracy, is proposed. This technique combines a three-dimensional ray launching algorithm based on geometrical optics with a diffusion equation method based on the equation of transfer. A comparison between the geometrical optics-only approach and the new method considering the diffusion equation has been presented for studying indoor radiowave propagation. The geometrical optics–diffusion equation method achieves better agreement with measurements, while resulting in high computational efficiency, with approximately 40% savings in simulation time.

A Hybrid Ray Launching-Diffusion Equation Approach for Propagation Prediction in Complex Indoor Environments

In this paper, a convergence analysis to obtain the optimal calculation parameters in an inhouse 3D ray launching algorithm to model the radio wave propagation channel in complex indoor environments is presented. Results show that these parameters lead to accurate estimations with reduced computational time. In addition, simulation results of an indoor complex scenario in terms of received power and power delay profile are presented, showing significant influence of multipath propagation in an indoor radio channel. The adequate election of simulation parameters given by convergence conditions, can aid in optimizing required computational time.

Convergence Analysis in Deterministic 3D Ray Launching Radio Channel Estimation in Complex Environments


 
 
 To compare the maternal and neonatal effects of cervical cerclage and vaginal progesterone in preventing singleton preterm births in women with a short cervical length.
 
 
 
 Cervical cerclage showed no benefit in preventing preterm birth; however, it prolonged gestation by 39 days compared to vaginal progesterone treatment.
 
 
 
 Clinically, there may be a bias toward the choice of cervical cerclage if the cervix is short (<10 mm) and, similarly, toward vaginal progesterone use if the cervix is long (>30 mm). However, there are no clear treatment guidelines for the best options for singleton pregnant women with a CL between 10 and 30 mm. Furthermore, there is insufficient evidence to determine whether one treatment is superior to the other in preventing PTB and decreasing adverse neonatal outcomes in singleton pregnancies in such cases.
 
 
 
 Asymptomatic pregnant women having singleton pregnancies, with a CL between 10 and 30 mm, measured using transvaginal ultrasound at 12–26 weeks of gestation, who delivered at our hospital between January 2009 and August 2020, were included in our study. Based on the inclusion and exclusion criteria, 267 singleton pregnant women, of whom 116 were treated with cervical cerclage and 151 with vaginal progesterone, were finally included.
 
 
 
 Independent sample t-tests and differential analysis were used to analyze the data based on their distribution. The Cox semi-parametric regression model was used to analyze the gestation weeks at delivery and neonatal outcomes. The decision regarding cesarean delivery was based on a binary logistic regression model.
 
 
 
 In the initial analysis, the number of preterm births was significantly higher in the cerclage group than in the vaginal progesterone group; however, after multivariate adjustment for confounding factors, the latency period from diagnosis to delivery was found to be significantly prolonged in the cerclage group.
 
 
 
 There are currently no uniform criteria for determining whether study subjects are eligible for cervical cerclage or vaginal progesterone treatment, which may present some cases of noncompliance.
 
 
 
 In our study, we found that cervical cerclage did not have significant advantages over vaginal progesterone treatment in preventing PTB. However, upon adjustment for confounding factors, it was shown to prolong the gestational age by 39 days compared to vaginal progesterone treatment.
 
 
 
 non-clinical trials


P-752 Cervical cerclage versus vaginal progesterone in the prevention of preterm birth in singleton pregnancies among women with a short cervical length: A retrospective cohort study

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Convergence Analysis in Deterministic 3D Ray Launching Radio Channel Estimation in Complex Environments

P-752 Cervical cerclage versus vaginal progesterone in the prevention of preterm birth in singleton pregnancies among women with a short cervical length: A retrospective cohort study