15 research outputs found
Wireless power transmission: R&D activities within Europe
Wireless power transmission (WPT) is an emerging technology that is gaining increased visibility in recent years. Efficient WPT circuits, systems and strategies can address a large group of applications spanning from batteryless systems, battery-free sensors, passive RF identification, near-field communications, and many others. WPT is a fundamental enabling technology of the Internet of Things concept, as well as machine-to-machine communications, since it minimizes the use of batteries and eliminates wired power connections. WPT technology brings together RF and dc circuit and system designers with different backgrounds on circuit design, novel materials and applications, and regulatory issues, forming a cross disciplinary team in order to achieve an efficient transmission of power over the air interface. This paper aims to present WPT technology in an integrated way, addressing state-of-the-art and challenges, and to discuss future R&D perspectives summarizing recent activities in Europe.The work of N. Borges Carvalho and A. J. S. Soares Boaventura was supported by the Portuguese Foundation for Science and Technology (FCT) under Project CREATION EXCL/EEI-TEL/0067/2012 and Doctoral Scholarship SFRH/BD/80615/2011. The work of H. Rogier was supported by BELSPO through the IAP Phase VII BESTCOM project and the Fund for Scientific Research-Flanders (FWO-V). The work of A. Georgiadis and A. Collado was supported by the European Union (EU) under Marie Curie FP7-PEOPLE-2009-IAPP 251557 and the Spanish Ministry of Economy and Competitiveness Project TEC 2012-39143. The work of J. A. GarcĂa and M. N. RuĂz was supported by the Spanish Ministries MICINN and MINECO under FEDER co-funded Project TEC2011-29126-C03-01 and Project CSD2008-00068. The work of J. Kracek and M. Mazanek was supported in part by the Czech Ministry of Education Youth and Sports under Project OC09075âNovel Emerging Wireless Systems
Unveiling ASEANâs Diplomatic Equilibrium: Assessing Member Nation-Statesâ Responses to Russiaâs Attack on Ukraine amidst the Rivalry between United States and China
Since the beginning of Russiaâs attack on Ukraine in 2022, the stance of the Association of Southeast Asian Nations (ASEAN) towards the crisis has been grounded on one of its core principles as a regional blocânon-interference, with member nation-states expressing varying levels of concern, neutrality, and implicit condemnation. ASEAN as a supranational institution trying to consolidate power in the regionâs security, economy, and diplomacy has attracted the eyes of the global powers, such as the United States (US) and China, as they seek support in resolving the conflict and advancing their own interests. With Russiaâs invasion of Ukraine at the backdrop, the Sino-US rivalry has intensified in the region through their strategic attempts in influencing the Southeast Asian (SEA) nation-statesâ stance in the on-going crisis. It is on this premise that this paper delves into several key interwoven politico-economic relations and historical ties that justify ASEAN member nation-statesâ responses in the crisis by (1) tracing the SEA governmentsâ immediate responses, (2) comparing proactive measures taken by these governments to pursue decisions that align with their respective interests, (3) examining the bases of SEA statesâ actions and public responses, (4) probing into the existing varying interests among SEA governments, and (5) establishing the links between SEA governmentsâ responses to that of US and China. This research contributes to a deeper understanding of ASEANâs roles and actions in global politics, specifically in dealing with issues on peace, security, and stability, amidst the intricate geopolitical landscape of the Asia-Pacific region
The effects of online sports training on the athletic performance and academic performance of De La Salle Medical and Health Sciences Institute Special Health Sciences Senior High School student-athletes
Experimental architecture for synchronized recordings of cerebral, muscular and biomechanical data during lower limb activities
In this paper, an architecture that allows the synchronized recording of cerebral, muscular and biomechanical data during lower limb activities has been designed. The synchronization issue has been addressed. The goal is to analyze the relationship between the different signals, first during simple lower limbs movements, then extending the analysis to gait. Five incomplete spinal cord injury patients and four healthy users participated in experiments to validate the architecture. The users were asked to perform simple movements that involve only one or two joints, particularly knee and ankle. Future studies with the recorded data will address several issues, such as creating neuromusculoskeletal models that relate kinematics data with EMG information, improving the decoding of the angles of the lower limb through EEG signals, or analyzing the coherence between the EEG signals and the EMG information
Design and Implementation of RF Energy Harvesting System for Low-Power Electronic Devices
Energy-Harvesting Fabric Antenna
In this chapter the exploitation of novel fabrics, in place of standard substrates and metallizations, in the realization of radio-frequency energy harvesting systems, commonly referred as rectennas, rectifying antennas, for Body Area Network applications is deeply discussed. The use of these unconventional materials makes the design approach a delicate issue: firstly, the electromagnetic characterization of fabrics is needed; furthermore, the effects of bending of the whole system, as well as the proximity to human tissue must be considered in the optimization procedure. The consequences of an approximate approach in the design of wearable rectennas could lead to significant deviations from the final prototypes performance. For these reasons we consider a computer-aided platform, which relies on the combination of full-wave solvers and nonlinear circuit-level tools, through the rigorous application of the electromagnetic theory: this way the unavoidable electromagnetic couplings between different system sections, the dispersive/nonlinear behavior of the entire rectenna. In this way the actual available power at the rectifier input port are accurately taken into account. The procedure is deeply described in this chapter through the step-wise analysis of the project of a fully wearable, fully autonomous tri-band rectenna. The experimental characterization of the prototype is used to provide a validation of the design procedure. The two-step procedure consists in the design of the rectenna with a fixed-load in radio-frequency (RF) stationary conditions, followed by the transient baseband design of the power management unit which acts as a dynamically variable load, depending on the actual incident RF power