The concept of an intelligent reflecting surface (IRS) has recently emerged as a promising solution for improving the coverage and energy/spectral efficiency of future wireless communication systems. However, as the number of reflecting elements in an IRS increase, the beam training protocol in IRS-assisted millimeter-wave (mmWave) cellular systems requires a large beam training time because it needs to find the best beam pairs for the link between the base station (BS) and the IRS, as well as the link between the IRS and the mobile station (MS). In this paper, a fast beam training technique for IRS-assisted mmWave cellular systems with a uniform rectangular array is proposed for detecting the best beam pairs of BS-IRS and IRS-MS links simultaneously. Two different types of beam training signals (BTSs) are proposed to distinguish simultaneously transmitted beams from the BSs in multi-cell multi-beam environments: the Zadoff-Chu sequence based BTS (ZC-BTS) and m-sequence based BTS (m-BTS). The correlation properties of ZC-BTSs and m-BTSs are analyzed in multi-cell multi-beam environments. In addition, the effect of symbol time offset on the ZC-BTS and m-BTS is analyzed. Finally, simulation results reveal that the proposed technique can significantly reduce the beam training time for IRS-assisted mmWave cellular systems.
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http://dx.doi.org/10.3390/s21144936 | DOI Listing |
Aging (Albany NY)
January 2025
School of Nutrition and Health Sciences, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan.
One of the key hallmarks of Parkinson's disease is the disruption of lipid homeostasis in the brain, which plays a critical role in neuronal membrane integrity and function. Understanding how treadmill training impacts lipid restructuring and its subsequent influence on motor function could provide a basis for developing targeted non-pharmacological interventions for individuals living with early stage of PD. This study aims to investigate the effects of a treadmill training intervention on motor deficits induced by 6-OHDA in rats model of PD.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
University of Virginia, Charlottesville, VA, USA.
Background: DNA methylation (DNAm) age measures, or 'epigenetic clocks', surpass chronological age in their ability to predict age-related morbidities and mortality. The Louisville Twin Study (LTS) presents an opportunity to clarify the role of early life environmental exposures and development in biological and cognitive aging in midlife. We expect that second-generation DNAm age measures trained to predict age related outcomes and death, independent of chronological age, will be sensitive to cognitive ability in midlife.
View Article and Find Full Text PDFHeliyon
November 2024
Department of Industrial Engineering and Automotive, Nebrija University, Santa Cruz de Marcendo 27, 28040, Madrid, Spain.
The use of numerical methods for structural analysis has been increasingly integrated within the design process in different engineering fields over the last decades, inasmuch as the capacity of the computing resources have growth. This gave rise to calculation techniques based on virtual models such as the finite element method, which is nowadays a reference method for evaluation of complex tubular structures with vast application in the industry. For such type of structures, modeling approaches based on beam type elements are usually employed since they provide simplicity and low computational costs.
View Article and Find Full Text PDFRadiat Oncol J
December 2024
Department of Radiation Oncology, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India.
Insights Imaging
January 2025
Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
Objectives: To propose a reliable and standard 3D assessment method to analyze the effect of weight-bearing (WB) status on the location of patella and clarify the diagnostic performance of 3D parameters for recurrent patellar dislocation (RPD) in WB and non-weight-bearing (NWB) conditions.
Methods: Sixty-five knees of RPD patients and 99 knees of controls were included. Eight landmarks, two lines and a coordinate system were defined on 3D bone models of knees based on weight-bearing CT and non-weight-bearing CT.
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