| 1. |
- Luque, R., et al.
(författare)
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A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067
- 2023
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 623:7989, s. 932-937
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Tidskriftsartikel (refereegranskat)abstract
- Planets with radii between that of the Earth and Neptune (hereafter referred to as ‘sub-Neptunes’) are found in close-in orbits around more than half of all Sun-like stars 1,2. However, their composition, formation and evolution remain poorly understood 3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R ⊕ to 2.85R ⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.
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| 2. |
- Munari, Andrea, et al.
(författare)
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A Stochastic Geometry Approach to Asynchronous Aloha Full-Duplex Networks
- 2017
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Ingår i: IEEE/ACM Transactions on Networking. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 1063-6692 .- 1558-2566. ; 25:6, s. 3695-3708
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Tidskriftsartikel (refereegranskat)abstract
- In-band full-duplex is emerging as a promising solution to enhance throughput in wireless networks. Allowing nodes to simultaneously send and receive data over the same bandwidth can potentially double the system capacity, and a good degree of maturity has been reached for physical layer design, with practical demonstrations in simple topologies. However, the true potential of full-duplex at a system level is yet to be fully understood. In this paper, we introduce an analytical framework based on stochastic geometry that captures the behavior of large full-duplex networks implementing an asynchronous random access policy based on Aloha. Via exact expressions, we discuss the key tradeoffs that characterize these systems, exploring among the rest the role of transmission duration, imperfect self-interference cancellation, and fraction of full-duplex nodes in the network. We also provide protocol design principles, and our comparison with slotted systems sheds light on the performance loss induced by the lack of synchronism.
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| 3. |
- Munari, Andrea, et al.
(författare)
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Stochastic Geometry Interference Analysis of Radar Network Performance
- 2018
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Ingår i: IEEE Communications Letters. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 1089-7798 .- 1558-2558. ; 22:11, s. 2362-2365
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Tidskriftsartikel (refereegranskat)abstract
- This letter characterizes the effect of mutual interference in a planar network of pulsed-radar devices. Using stochastic geometry tools and the strongest interferer approximation, we derive simple closed-form expressions that pinpoint the role played by key system parameters on radar detection range and false alarm rate. The fundamental tradeoffs of the system between radar performance, network density, and antenna directivity are captured for different path-loss exponents in the no-fading and Rayleigh-fading cases. The discussion highlights practical design hints for tuning the radar parameters. The accuracy of the model is verified through network simulations.
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| 4. |
- Picetti, Edoardo, et al.
(författare)
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Early management of adult traumatic spinal cord injury in patients with polytrauma : a consensus and clinical recommendations jointly developed by the World Society of Emergency Surgery (WSES) & the European Association of Neurosurgical Societies (EANS)
- 2024
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Ingår i: World Journal of Emergency Surgery. - : BioMed Central (BMC). - 1749-7922. ; 19
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Tidskriftsartikel (refereegranskat)abstract
- Background: The early management of polytrauma patients with traumatic spinal cord injury (tSCI) is a major challenge. Sparse data is available to provide optimal care in this scenario and worldwide variability in clinical practice has been documented in recent studies.Methods: A multidisciplinary consensus panel of physicians selected for their established clinical and scientific expertise in the acute management of tSCI polytrauma patients with different specializations was established. The World Society of Emergency Surgery (WSES) and the European Association of Neurosurgical Societies (EANS) endorsed the consensus, and a modified Delphi approach was adopted.Results: A total of 17 statements were proposed and discussed. A consensus was reached generating 17 recommendations (16 strong and 1 weak).Conclusions: This consensus provides practical recommendations to support a clinician's decision making in the management of tSCI polytrauma patients.
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| 5. |
- Ren, P., et al.
(författare)
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Performance Analysis of a Time-sharing Joint Radar-Communications Network
- 2020
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Ingår i: 2020 International Conference on Computing, Networking and Communications, ICNC 2020. - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 908-913
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Konferensbidrag (refereegranskat)abstract
- In the last few years there has been an increased interest towards convergence of communication and sensing functions in the future networks, in order to provide high-datarate wireless and mobile services. In particular, the co-existence and joint operation of radar and communication (comm) systems has emerged as a key research area. In this paper we study the performance of a time-sharing joint radar-comm network and propose approximation methods to obtain two key performance metrics, namely the radar range and comm success probability. We consider a set of radar-communication devices following a homogeneous Poisson point process. Each device works as a pulsed radar and a comm node in turn over time. The analytical results, which we verify via simulations, give important insights on how to trade between radar update rate, comm packet length and network performance.
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| 6. |
- Ren, Ping, et al.
(författare)
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Performance Tradeoffs of Joint Radar-Communication Networks
- 2019
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Ingår i: IEEE Wireless Communications Letters. - : IEEE. - 2162-2337 .- 2162-2345. ; 8:1, s. 165-168
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Tidskriftsartikel (refereegranskat)abstract
- This letter considers a network where nodes share a wireless channel to work in turn as pulse radars for target detection and as transmitters for data exchange. Radar detection range and network throughput are studied using stochastic geometry tools. We derive closed-form expressions that identify the key tradeoffs between radar and communication operations. Results reveal interesting design hints, and stress a marked sensitivity of radar detection to communication interference.
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