Search results for "Aerial"

Assessment of Coastal Vulnerability in South Sicily

2006

Medium-term shoreline evolution of the mediterranean coast of Andalusia (SW Spain)

2015

Coastal environment is a dynamic system in which numerous natural processes are continuously actuating and interacting among them. As a result, geomorphologic, physical and biological characteristics of coastal environments are constantly changing. Such dynamic balance is nowadays seriously threatened by the strong and increasing anthropic pressure that favors erosion processes, and the associated loss of environmental, ecologic and economic aspects. Sandy beaches are the most vulnerable environments in coastal areas. The aim of this work was to reconstruct the historical evolution of the Mediterranean coastline of Andalusia, Spain. The investigated area is about 500 km in length and includ…

UAV-Assisted Data Collection in Wireless Sensor Networks: A Comprehensive Survey

2021

Wireless sensor networks (WSNs) are usually deployed to different areas of interest to sense phenomena, process sensed data, and take actions accordingly. The networks are integrated with many advanced technologies to be able to fulfill their tasks that is becoming more and more complicated. These networks tend to connect to multimedia networks and to process huge data over long distances. Due to the limited resources of static sensor nodes, WSNs need to cooperate with mobile robots such as unmanned ground vehicles (UGVs), or unmanned aerial vehicles (UAVs) in their developments. The mobile devices show their maneuverability, computational and energy-storage abilities to support WSNs in mul…

Drones in cyber security environment

2019

Aerial unmanned vehicles (AUV) are currently used for a wide range of operations such as border surveillance, surveillance, reconnaissance, transport, aerial photography, traffic control, earth observation, communications, broadcasting and armed attacks. AUVs are presumed to be reliable, automated and autonomous machines. AUVs are extremely suitable for long missions that strain flight crews or put them to harm's way. Two advantages can be gained by eliminating the flight crew: 1) performance improves (range, endurance, increased payload and maneuverability, smaller physical size and lower observability) and; 2) the ability to take higher risks. UAV/RPAS/drone cyber security has largely foc…

Aproximación al higienismo en la arquitectura de Rafael Guastavino

2021

La obra de Rafael Guastavino Moreno (1842-1908) está vinculada habitualmente a la construcción con bóveda tabicada, un sistema constructivo tradicional originario del Levante peninsular que este arquitecto combinó con el mortero de cemento para erigir un gran número de edificios de muy diverso tipo tanto en Barcelona como posteriormente en Estados Unidos. Sin embargo, estos autores han defendido en otras ocasiones la versatilidad de Guastavino como arquitecto y hasta qué punto la bóveda tabicada no supuso en un principio el cuaderno de bitácora único ni principal para su trayectoria profesional. La bóveda tabicada representó una herramienta más en la panoplia de sus habilidades, entre las c…

Unmanned aerial vehicle measurements of volcanic carbon dioxide fluxes

2008

[i] We report the first measurements of volcanic gases with an unmanned aerial vehicle (UAV). The data were collected at La Fossa crater, Vulcano, Italy, during April 2007, with a helicopter UAV of 3 kg payload, carrying an ultraviolet spectrometer for remotely sensing the SO 2 flux (8.5 Mg d- 1 ), and an infrared spectrometer, and electrochemical sensor assembly for measuring the plume CO 2 /SO 2 ratio; by multiplying these data we compute a CO 2 flux of 170 Mg d -1 . Given the deeper exsolution of carbon dioxide from magma, and its lower solubility in hydro-thermal systems, relative to SO 2 , the ability to remotely measure CO 2 fluxes is significant, with promise to provide more profound…

UAV-Aided Secure Short-Packet Data Collection and Transmission

2023

Benefiting from the deployment flexibility and the line-of-sight (LoS) channel conditions, unmanned aerial vehicle (UAV) has gained tremendous attention in data collection for wireless sensor networks. However, the high-quality air-ground channels also pose significant threats to the security of UAV aided wireless networks. In this paper, we propose a short-packet secure UAV-aided data collection and transmission scheme to guarantee the freshness and security of the transmission from the sensors to the remote ground base station (BS). First, during the data collection phase, the trajectory, the flight duration, and the user scheduling are jointly optimized with the objective of maximizing t…

Joint Sub-Carrier and Power Allocation for Efficient Communication of Cellular UAVs

2020

| openaire: EC/H2020/857031/EU//5G!Drones Cellular networks are expected to be the main communication infrastructure to support the expanding applications of Unmanned Aerial Vehicles (UAVs). As these networks are deployed to serve ground User Equipment (UEs), several issues need to be addressed to enhance cellular UAVs’ services. In this paper, we propose a realistic communication model on the downlink, and we show that the Quality of Service (QoS) for the users is affected by the number of interfering BSs and the impact they cause. The joint problem of sub-carrier and power allocation is therefore addressed. Given its complexity, which is known to be NP-hard, we introduce a solution based …

BVLOS UAS Operations in Highly-Turbulent Volcanic Plumes.

2020

Long-range, high-altitude Unoccupied Aerial System (UAS) operations now enable in-situ measurements of volcanic gas chemistry at globally-significant active volcanoes. However, the extreme environments encountered within volcanic plumes present significant challenges for both air frame development and in-flight control. As part of a multi-disciplinary field deployment in May 2019, we flew fixed wing UAS Beyond Visual Line of Sight (BVLOS) over Manam volcano, Papua New Guinea, to measure real-time gas concentrations within the volcanic plume. By integrating aerial gas measurements with ground- and satellite-based sensors, our aim was to collect data that would constrain the emission rate of …

Volcanic Gas Emissions Along the Colombian Arc Segment of the Northern Volcanic Zone (CAS-NVZ): Implications for volcano monitoring and volatile budg…

2019

Studying spatial and temporal trends in volcanic gas compositions and fluxes is crucial both to volcano monitoring and to constrain the origin and recycling efficiency of volatiles at active convergent margins. New volcanic gas compositions and volatile fluxes are here reported for Nevado del Ruiz, Galeras, and Purace, three of the most persistently degassing volcanoes located in the Colombian Arc Segment of the Northern Volcanic Zone. At Nevado del Ruiz, from 2014 to 2017, plume emissions showed an average molar CO2/S-T ratio of 3.9 +/- 1.6 (S-T is total sulfur, S). Contemporary, fumarolic chemistry at Galeras progressively shifted toward low-temperature, S-depleted fumarolic gas discharge…