Results 71 to 80 of about 6,983 (148)
Diagnostic Performance of Ultrasound in Adult Appendicitis. A Retrospective Review of 331 Cases
Journal of Medical Radiation Sciences, EarlyView.The sensitivity of ultrasound in the detection of appendicitis had a prevalence of 16% in our predominantly young female cohort, with alternative gynaecological and abdominal diagnoses identified approximately 2:1. The sensitivity for ultrasound to detect appendicitis was 60%, with specificity of 98% and negative predictive value (NPV) of 93%.
Alistair Lock, Martin Necas
wiley +1 more source
Robust Monotonic Optimization Framework for Multicell MISO Systems
, 2012 The performance of multiuser systems is both difficult to measure fairly and to optimize. Most resource allocation problems are non-convex and NP-hard, even under simplifying assumptions such as perfect channel knowledge, homogeneous channel properties ...
Bengtsson, Mats +3 more
core +1 more source
Non‐Uniform Programmable Photonic Waveguide Meshes
Laser &Photonics Reviews, EarlyView.Integrating defect cells into uniform hexagonal waveguide meshes overcomes the fundamental spectral and temporal limitations of programmable photonics. By leveraging the Vernier effect through non‐uniform coupled cavities, this architecture achieves a tenfold increase in free spectral range and ultra‐fast sampling times, paving the way for next ...
Cristina Catalá‐Lahoz, José Capmany
wiley +1 more source
Multicast Multigroup Beamforming under Per-antenna Power Constraints
, 2014 Linear precoding exploits the spatial degrees of freedom offered by multi-antenna transmitters to serve multiple users over the same frequency resources.
Chatzinotas, Symeon +2 more
core +1 more source
Coordinated adaptive beamformer over distributed antenna network
Chinese Journal of Aeronautics, 2013 AbstractThe spatial diversity of distributed network demands the individual filter to accommodate the topology of interference environment. In this paper, a type of distributed adaptive beamformer is proposed to mitigate interference over coordinated antenna arrays network.
Liu, Desheng +3 more
openaire +1 more source
International Journal of Satellite Communications and Networking, EarlyView.ABSTRACT This study analyzes the architecture of the beyond 5G‐NTN (Non‐terrestrial Network) integrated network and presents the technical, legal, and regulatory challenges and considerations for expanding the Artificial Intelligence of Things (AIoT) ecosystem.
Byung Woon Kim, Ga Eun Choi
wiley +1 more source
Coordinated beamforming for cognitive multi-cell networks with wiretap channels
Tongxin xuebao, 2014 Owing to the coupling among the vectors to be optimized，the problem becomes non-convex and non-linear.Accordingly，a centralized coordinated beamforming design method was proposed by constraining the leakage interference and using the semi-definite ...
Dong-hua CHEN, Xiu-xiu ZHANG, Wei-bo XIE
doaj +2 more sources
Robust Iterative Interference Alignment for Cellular Networks with Limited Feedback
, 2014 In theory coordinated multi-point transmission (CoMP) promises vast gains in spectral efficiency. But industrial field trials show rather disappointing throughput gains, whereby the major limiting factor is proper sharing of channel state information ...
Jung, Peter +2 more
core +1 more source
International Journal of Satellite Communications and Networking, EarlyView.ABSTRACT As non‐terrestrial networks (NTNs) become integral to future 6G systems, ensuring seamless connectivity and service continuity over low Earth orbit (LEO) satellite constellations is essential. This work investigates the impact of open radio access network (RAN) functional splits on handover performance in NTNs, focusing on minimizing service ...
Siva Satya Sri Ganesh Seeram +3 more
wiley +1 more source
IEEE Access, 2019 Cloud-radio access networks (C-RAN) help in overcoming the scarcity of radio resources by enabling dense deployment of base-stations (BSs) and connecting them to a central-processor (CP).
Alaa Alameer Ahmad +4 more
doaj +1 more source