Model fitting to account for the weather s impact on wireless propagation at 2.4 GHz

[EN] Usually, users of outdoor wireless local area networks have a good quality of experience and they do not have any complaint about its performance. However, under certain weather conditions, their performance decreases due to influence of meteorological variables on wireless signal propagation and users notice this deterioration through disconnections, delays, data loss, etc. This paper presents the research carried out in order to approach the unsuccessful transmission of different frames at MAC layer from the weather conditions at run time by using mathematic models.This work has been supported by the Vice-Rectorate for Research, Innovation and Transfer through the programme FPI-UPV. The authors would like to thank Borja Opticos and Azimut Electronics for their support.Bri Molinero, D.; Garcia, M.; Lloret, J.; Ramos, F. (2017). Model fitting to account for the weather s impact on wireless propagation at 2.4 GHz. National Academy Science Letters. 40(2):127-130. https://doi.org/10.1007/s40009-016-0520-7S127130402Bianchi C, Meloni A (2007) Natural and man-made terrestrial electromagnetic noise: an outlook. Ann Geophys 50:435–445International Telecommunications Union (2013) Recommendation ITU-R P.676-10: attenuation by atmospheric gasesInternational Telecommunications Union (2013) Recommendation ITU-R P.530-15: propagation data and prediction methods required for the design of terrestrial line-of-sight systemsBri D, Fernández-DiegoM Garcia M, Ramos F, Lloret J (2012) How the weather impacts on the performance of an outdoor WLAN. IEEE Commun Lett 6:1184–1187Bri D, Ramos F, Lloret J, Garcia M (2012) The influence of meteorological variables on the performance of outdoor wireless local area networks. In: IEEE international conference on communications, OttawaBri D, Sendra S, Coll H, Lloret J (2010) How the atmospheric variables affect to the WLAN Datalink layer parameters. In: Advanced international conference on telecommunications, BarcelonaChu CH, Chen YM, Huang YT, Carvalho R, Hsu CC, Chen LJ (2014) Measurement of long-distance Wi-Fi connections: an empirical study. In: IEEE international conference on communications, SydneyOhshima K, Hara H, Hagiwara Y, Terada M (2012) Field investigation of the radio transmission performance and distance in an environmental wireless sensor network. In: International conference on information networking, BaliNadeem F, Leitgeb E, Koudelka O, Kandus TJG (2008) Comparing the rain effects on hybrid network using optical wireless and GHz links. In: International conference on emerging technologies, RawalpindiSchmidt M, Lipson H (2009) Distilling free-form natural laws from experimental data. Science 324:81–85Schmidt M, Lipson H (2013) Eureqa (Version 0.98 beta) [Software] Available: www.nutonian.comBri D, Garcia M, Lloret J, Misic J (2015) Measuring the weather’s impact on MAC layer over 2.4 GHz outdoor radio links. Measurement 61:221–233Yu F, Biswas S (2012) MAC protocol switching: a novel tool for performance adaptation in wireless sensor networks. Netw Protoc Algor 4:69–8

VLIT NODE Sensor Technology and Prefarm

Precision farming systems are based on a detailed monitoring of information and data that are necessary for successful decision-making in crop production. The system is designed for data collection from several resources. In past years an extensive research and development work has been done in the field of wireless sensor networks (WSN) in the world. When a wireless sensor network (WSN) is used for agricultural purposes, it has to provide first of all a long-reach signal. The present paper describes new long distance RFID based technology implementation - VLIT NODE.Wireless Sensor Network, Precision Agriculture, RFID., Research and Development/Tech Change/Emerging Technologies, Research Methods/ Statistical Methods, GA, IN,

Low-Cost Air Quality Monitoring Tools: From Research to Practice (A Workshop Summary).

In May 2017, a two-day workshop was held in Los Angeles (California, U.S.A.) to gather practitioners who work with low-cost sensors used to make air quality measurements. The community of practice included individuals from academia, industry, non-profit groups, community-based organizations, and regulatory agencies. The group gathered to share knowledge developed from a variety of pilot projects in hopes of advancing the collective knowledge about how best to use low-cost air quality sensors. Panel discussion topics included: (1) best practices for deployment and calibration of low-cost sensor systems, (2) data standardization efforts and database design, (3) advances in sensor calibration, data management, and data analysis and visualization, and (4) lessons learned from research/community partnerships to encourage purposeful use of sensors and create change/action. Panel discussions summarized knowledge advances and project successes while also highlighting the questions, unresolved issues, and technological limitations that still remain within the low-cost air quality sensor arena

Weather and Climate Information for Tourism

The tourism sector is one of the largest and fastest growing global industries and is a significant contributor to national and local economies around the world. The interface between climate and tourism is multifaceted and complex, as climate represents both a vital resource to be exploited and an important limiting factor that poses risks to be managed by the tourism industry and tourists alike. All tourism destinations and operators are climate-sensitive to a degree and climate is a key influence on travel planning and the travel experience. This chapter provides a synopsis of the capacities and needs for climate services in the tourism sector, including current and emerging applications of climate services by diverse tourism end-users, and a discussion of key knowledge gaps, research and capacity-building needs and partnerships that are required to accelerate the application of climate information to manage risks to climate variability and facilitate successful adaptation to climate change

Weather and Climate Information for Tourism

The tourism sector is one of the largest and fastest growing global industries and is a significant contributor to national and local economies around the world. The interface between climate and tourism is multifaceted and complex, as climate represents both a vital resource to be exploited and an important limiting factor that poses risks to be managed by the tourism industry and tourists alike. All tourism destinations and operators are climate-sensitive to a degree and climate is a key influence on travel planning and the travel experience. This chapter provides a synopsis of the capacities and needs for climate services in the tourism sector, including current and emerging applications of climate services by diverse tourism end-users, and a discussion of key knowledge gaps, research and capacity-building needs and partnerships that are required to accelerate the application of climate information to manage risks to climate variability and facilitate successful adaptation to climate change

Weather and Climate Information for Tourism

The tourism sector is one of the largest and fastest growing global industries and is a significant contributor to national and local economies around the world. The interface between climate and tourism is multifaceted and complex, as climate represents both a vital resource to be exploited and an important limiting factor that poses risks to be managed by the tourism industry and tourists alike. All tourism destinations and operators are climate-sensitive to a degree and climate is a key influence on travel planning and the travel experience. This chapter provides a synopsis of the capacities and needs for climate services in the tourism sector, including current and emerging applications of climate services by diverse tourism end-users, and a discussion of key knowledge gaps, research and capacity-building needs and partnerships that are required to accelerate the application of climate information to manage risks to climate variability and facilitate successful adaptation to climate change

Assessment of portable and miniaturized sensors for the monitoring of human exposure to air pollutants

In the last years, several in-field campaigns have been conducted using portable and miniaturized monitors to evaluate the personal exposure to different pollutants. In general, this kind of monitors are characterized by worse metrological performance if compared to the traditional standard methods. Despite this disadvantage, portable and miniaturized monitors could be easily used across different applications, because their advantageous features, such as the capability to provide real-time measurement, the high spatial and temporal resolution of acquired data, the ability to adapt to different experimental designs and, especially, the ability to follow the subject in any activity. Finally, portable and miniaturized instruments can provide data acquired in the respiratory zone of the subject, following therefore the practices for a correct exposure assessment. Obviously, the best compromise between the analytical gold standard (in terms of precision, accuracy and instrumental sensitivity) and the gold standard in regard to the exposure assessment should be chosen. Therefore, in brief, principal aims of this thesis are (i) to evaluate the on-field performances of portable and miniaturized monitors for gaseous pollutants and airborne PM and (ii) to use these monitors in exposure assessment studies and (iii) to understand if data acquired via portable and miniaturized monitors could be useful in other fields of application, such as epidemiological studies or toxicological studies, in which the evaluation of the inhaled dose of pollutants could play a key role

Mini-UAV Based Sensory System for Measuring Environmental Variables in Greenhouses

This paper describes the design, construction and validation of a mobile sensory platform for greenhouse monitoring. The complete system consists of a sensory system on board a small quadrotor (i.e., a four rotor mini-UAV). The goals of this system include taking measures of temperature, humidity, luminosity and CO2 concentration and plotting maps of these variables. These features could potentially allow for climate control, crop monitoring or failure detection (e.g., a break in a plastic cover). The sensors have been selected by considering the climate and plant growth models and the requirements for their integration onboard the quadrotor. The sensors layout and placement have been determined through a study of quadrotor aerodynamics and the influence of the airflows from its rotors. All components of the system have been developed, integrated and tested through a set of field experiments in a real greenhouse. The primary contributions of this paper are the validation of the quadrotor as a platform for measuring environmental variables and the determination of the optimal location of sensors on a quadrotor.This work has been supported by the Robotics and Cybernetics Research Group at Technical University of Madrid (Spain) and has been funded under the projects “ROTOS: Multi-robot system for outdoor infrastructures protection”, sponsored by the Spanish Ministry of Education, Culture and Sport (DPI2010-17998); the “ROBOCITY 2030 Project”, sponsored by the Autonomous Community of Madrid (S-0505/DPI/ 000235); and the SAVIER Project, sponsored by Airbus Defence & Space.Peer Reviewe