Search results for "angle"
showing 10 items of 1921 documents
Classification of Targets Using Statistical Features from Range FFT of mmWave FMCW Radars
2021
Radars with mmWave frequency modulated continuous wave (FMCW) technology accurately estimate the range and velocity of targets in their field of view (FoV). The targeted angle of arrival (AoA) estimation can be improved by increasing receiving antennas or by using multiple-input multiple-output (MIMO). However, obtaining target features such as target type remains challenging. In this paper, we present a novel target classification method based on machine learning and features extracted from a range fast Fourier transform (FFT) profile by using mmWave FMCW radars operating in the frequency range of 77–81 GHz. The measurements are carried out in a variety of realistic situations, including p…
RC Columns Strengthened with Steel Angles and Battens: Experimental Results and Design Procedure
2013
In this paper, an analytical model for the design of axially loaded strengthened RC columns with steel angles and battens is presented. Cases of directly loaded and not directly loaded steel angles are considered. The model considers the contribution in confinement pressures caused by transverse battens and steel angles and the contribution in terms of the load-carrying capacity of steel angles subjected to axial force and the bending moment. An experimental investigation on the compressive behavior of eight short, confined, RC columns externally strengthened with steel angles and steel battens with various pitches was carried out, and has been utilized as support for the analytical model. …
Load Distribution in the Lumbar Spine During Modeled Compression Depends on Lordosis.
2021
Excessive or incorrect loading of lumbar spinal structures is commonly assumed as one of the factors to accelerate degenerative processes, which may lead to lower back pain. Accordingly, the mechanics of the spine under medical conditions, such as scoliosis or spondylolisthesis, is well-investigated. Treatments via both conventional therapy and surgical methods alike aim at restoring a “healthy” (or at least pain-free) load distribution. Yet, surprisingly little is known about the inter-subject variability of load bearings within a “healthy” lumbar spine. Hence, we utilized computer tomography data from 28 trauma-room patients, whose lumbar spines showed no visible sign of degeneration, to …
Use of accelerometers and gyros for hip and knee angle estimation
2013
In this paper a wearable sensor system, consisting of accelerometers and gyros, has been studied to estimate hip and knee angles. The proposed algorithm, developed in order to avoid the error accumulation due to gyroscopes drift, has been tested on angle measurement of the hip and knee of a commercial device for assisted gait. The results have shown a good accuracy of the angles estimation, also in high angle rate movement
Ritz Solution for Transient Analysis of Variable-Stiffness Shell Structures
2020
The dynamic response of thin-walled structures is driven by mass and stiffness distribution. As such, variable-stiffness (VS) composites offer opportunities to tune structural dynamic responses. To this extent, efficient analysis tools become increasingly important for structural analysis and design purposes. In this work, an efficient and versatile Ritz method for free vibrations and linear transient analysis of VS doubly curved shell structures is presented. VS shell structures are modeled as an assembly of shell-like domains. The shell kinematics is based on the first-order shear deformation theory, and no further assumption is made on the shallowness or on the thinness of the structure.…
Reconstruction of vertebral body in thoracolumbar AO type A post-traumatic fractures by balloon kyphoplasty: a series of 85 patients with a long foll…
2019
Background Traumatic fractures of the thoracolumbar spine are common injuries, accounting for approximately 90% of all spinal traumas. Optimal management of these fractures still gives rises to much debate in the literature. Currently, one of the treatment options in young patients with stable traumatic vertebral fractures is conservative treatment using braces. Kyphoplasty as a minimally invasive procedure has been shown to be effective in stabilizing vertebral body fractures, resulting in immediate pain relief and improved physical function with early return to work activity. The aim of the study is to report VAS, ODI scores, and kyphosis correction following treatment. Methods This is a …
Preparation of Nd:YAG Nanopowder in a Confined Environment
2007
Nanopowder of yttrium aluminum garnet (YAG, Y3Al5O12) doped with neodymium ions (Nd:YAG) was prepared in the water/cetyltrimethylammonium bromide/1-butanol/n-heptane system. Aluminum, yttrium, and neodymium nitrates were used as starting materials, and ammonia was used as a precipitating agent. Coprecipitate hydroxide precursors where thermally treated at 900 degrees C to achieve the garnet phase. The starting system with and without reactants was characterized by means of the small-angle neutron scattering technique. The system, without reactants, is constituted by a bicontinuous structure laying near the borderline with the lamellar phase region. The introduction of nitrates stabilizes th…
Surface modification of poly(ethylene-co-acrylic acid) with amino-functionalized silica nanoparticles
2011
In this work we studied the possibility to achieve a hybrid-surface through the modification, via a facile wet chemical process, of the surface of films of poly(ethylene-co-acrylic acid) (EAA) with amino-modified silica nanoparticles. Films of EAA were preliminarily activated by the introduction of -COCl groups on their surface. Silica nanoparticles were thereafter covalently bound on the polymeric surface as confirmed by FTIR, ATR-FTIR, XPS, NMR and SEM determinations. The nanoparticles formed a multilayer on the film surface and covered almost uniformly the whole film surface. Direct measurements of superficial amino groups by titration allowed us to detect a concentration of about 18 nmo…
Morphology Influence on Wettability and Wetting Dynamics of ZnO Nanostructure Arrays
2022
This study has been supported by internal research grant No. 14-95/2021/10 of Daugavpils University “Development of the Nanostructured Metal Oxide Coatings and Their Application in Optical Sensing for Heavy Metal Detection”.
Optimizing the θ23 octant search in long baseline neutrino experiments
2017
Determination of the θ 23 octant will be an important goal for the next generation of neutrino oscillation experiments, as it will show whether the true value of θ 23 lies in the high octant, θ 23 > 45°, or in the low octant, θ 23 < 45°. In this work we investigate the prospects of studying the θ 23 octant in future long baseline neutrino experiments. Using the GLoBES software, we study the sensitivity to θ 23 octant in terms of baseline length and beam sharing and use the LBNO setup as our benchmark. We also show the interference on the octant determination that arises from the unconstrained CP violation angle δ CP. In our results, we show the impact of matter effects on the octant determi…