Variation Of Rotation Angle Research Articles

Abstract 11178: Non-Invasive Identification of Fibrotic Atrial Cardiomyopathy with Neural Networks Based on 642,400 12-Lead Ecgs from an Extensive Cohort Simulation Study

The clinical picture of fibrotic atrial cardiomyopathy is caused by a partial replacement of atrial myocardial tissue with fibrotic substrate. Being subject to electrical and structural remodeling processes, the substrate provides the necessary properties for the maintenance of atrial fibrillation and could thus be a good risk marker. We hypothesize that the P waves in the 12-lead ECG present a non-invasive and cost-effective tool to quantify the extent of atrial fibrosis as an alternative to state-of-the-art approaches. Our virtual patient cohort comprised a combination of 80 atrial, 25 thoracic geometries and 27 rotation angle variations of the atria. For each atrial model, 10 stages of fibrosis were defined by replacing different fractions of the myocardial volume with fibrotic tissue patches exhibiting remodeled ionic and conduction velocity properties. Conducting electrophysiological simulations in sinus rhythm on each model combination with one to three different healthy baseline conduction velocities yielded 642,400 synthetic ECGs. P wave duration, dispersion, peak-to-peak amplitudes and terminal force in V1 were calculated and served, together with atrial volumes and torso sizes, as an input for a regression neural network to estimate the volume fraction of atrial fibrosis. The root mean square error between the ground truth and the estimated extent of fibrosis was 8.74% left atrial fibrotic volume. Based on the regression results, a distinction between the healthy and the diseased cohorts was possible with an accuracy of 99.01%, a sensitivity of 99.57% and a specificity of 62.38%. In conclusion, we have gauged the potential of the 12-lead ECG for estimating fibrotic atrial volume fractions in an extensive cohort simulation study comprising both, functional and anatomical inter-subject variability. As a next step, the methods need to be validated with clinical data for which robust feature extraction algorithms are required.

Implementation of Differential Transform Method (DTM) for Large Deformation Analysis of Cantilever Beam

Large deformation of a cantilever beam is an eminent structural analysis and engineering problem. A non-linear differential equation governs the problem of large deformation of beams. It has many important applications scientific and engineering fields. It is quite intricate and complex to find a closed-form or an exact solution for such a problem. It is relatively easier to use analytic expressions for calculations than numerical or experimental analysis. Large deformation analysis has always been an active area of research for researchers. The main focus of this research is to implement a new method namely Differential Transformation Method (DTM) for non-linear beam problem analysis. DTM is quite reliable and efficient in giving an approximate analytical solution to beam problems. Moreover, it is a new application for DTM. Hence, the primary purpose of this work is to evaluate the utility of the method for solution of beam problem. DTM yields a 2-point boundary value problem. It is based Taylor’s series expansion. DTM helps to calculate the deflection angle and horizontal as well as vertical displacements of a cantilever beam, experiencing large deformation, in an explicit analytical form. Mathematical formulation code will be developed using MATLAB. Variation of rotation angle at free end will be analysed using different number of terms used and values of non-dimensional load “β”. Results of DTM prove the method to be quite effective and suitable for predicting solutions to non-linear beam problems. Therefore, DTM can be used for widespread applications for new, emerging and complex engineering problems.

Undistorted 180° phase reversal of magnetoelectric coupling in bi-layered multiferroic laminate

A methodology of rotating the applied static magnetic field on Ni0.8Zn0.2Fe2O4 (NZFO)/PZT-8 magnetoelectric laminate, was introduced to realize 180° phase reversal with constant amplitude, which is invariably required for phase-based communication system, engineering technology and microelectronic devices. Through further decoding the phase information existed in magnetoelectric coefficient, we found that the undistorted 180° phase reversal can be achieved once the applied field was reversed. Moreover, piezomagnetic response can essentially track the magnetoelectric response under optimum bias with the variations of rotation angle, and then the origins can be well explained. Experimental results show that the maximum resonance ME voltage coefficient of +51.72 V/cm Oe and −51.93 V/cm Oe were obtained in angle of θ = 0° and 180°, respectively. These results provide great possibilities for practical applications in ME phase shifters and inverters.

Design and analysis of high birefringence and nonlinearity with small confinement loss photonic crystal fiber

High birefringence with low confinement loss photonic crystal fiber (PCF) has significant advantages in the field of sensing, dispersion compensation devices, nonlinear applications, and polarization filter. In this report, two different models of PCFs are presented and compared. Both the models contain five air holes rings with combination of circular and elliptical air holes arrangement. Moreover, the elliptical shaped air holes polarization and the third ring air holes rotational angle are varied. To examine different guiding characteristics, finite element method (FEM) with perfectly matched layer (PML) absorbing boundary condition is applied from 1.2 to 1.8 μm wavelength range. High birefringence, low confinement loss, high nonlinearity, and moderate dispersion values are successfully achieved in both the PCFs models. Numeric analysis shows that model-1 gives higher birefringence (2.75 × 10–2) and negative dispersion (–540.67 ps/(nm$km)) at 1.55 μm wavelength. However, model-2 gives more small confinement loss than model-1 at the same wavelength. In addition, the proposed design demonstrates the variation of rotation angle has great impact to enhance guiding properties especially the birefringence.

An analysis of 3D knee kinematic data complexity in knee osteoarthritis and asymptomatic controls.

Three-dimensional (3D) knee kinematic data, measuring flexion/extension, abduction/adduction, and internal/external rotation angle variations during locomotion, provide essential information to diagnose, classify, and treat musculoskeletal knee pathologies. However, and so across genders, the curse of dimensionality, intra-class high variability, and inter-class proximity make this data usually difficult to interpret, particularly in tasks such as knee pathology classification. The purpose of this study is to use data complexity analysis to get some insight into this difficulty. Using 3D knee kinematic measurements recorded from osteoarthritis and asymptomatic subjects, we evaluated both single feature complexity, where each feature is taken individually, and global feature complexity, where features are considered simultaneously. These evaluations afford a characterization of data complexity independent of the used classifier and, therefore, provide information as to the level of classification performance one can expect. Comparative results, using reference databases, reveal that knee kinematic data are highly complex, and thus foretell the difficulty of knee pathology classification.

Risk Assessment of Face Skin Exposure to UV Irradiance from Different Rotation Angle Ranges.

Ultraviolet (UV) is one of the environmental pathogenic factors causing skin damage. Aiming to assess the risk of face skin exposure to UV irradiance from different rotation angles, a rotating model was used to monitor the exposure of the skin on the face to UV irradiance, with skin damage action spectra used to determine the biologically effective UV irradiance (UVBEskin) and UVBEskin radiant exposure (HBEskin) causing skin damage. The results indicate that the UVBEskin is directly influenced by variations in rotation angles. A significant decrease of approximately 52.70% and 52.10% in UVBEskin was found when the cheek and nose measurement sites was rotated from 0° to 90°, while a decrease of approximately 62.70% was shown when the forehead measurement sites was rotated from an angle of 0° to 108°. When HBEskin was compared to the exposure limits (ELs; 30 J·m−2), the maximum relative risk ratios (RR) for cheek, nose, and forehead were found to be approximately 2.01, 2.40, and 2.90, respectively, which were all measured at a rotation angle of 0°. The maximal increase in the percentage of the average HBEskin for rotation angles of 60°, 120°, 180°, and 360° facing the sun to ELs were found to be approximately 62.10%, 52.72%, 43.43%, and 26.27% for the cheek; approximately 130.61%, 109.68%, 86.43%, and 50.06% for the nose; and approximately 178.61%, 159.19%, 134.38%, and 83.41% for the forehead, respectively.

Aeroelastic Tailoring of a Representative Wing Box Using Tow-Steered Composites

There has been an increasing effort to improve aircraft performance through using composite tailored structures, not only to reduce weight, but to exploit beneficial aeroelastic couplings. Recent work has considered the ability to tow steer the composite plies to achieve better performance. Here, the potential wing weight savings of a full-size aeroelastically tailored wing are assessed by optimizing the properties of a three-dimensional finite element model using straight-fiber and tow-steered composites in the skins. One- and two-dimensional thickness and laminate rotation angle variations are considered as design freedoms. The jig shape is updated to maintain a fixed flight shape, and optimization constraints are implemented on the strains and buckling loads due to maneuver and dynamic gust loads, flutter stability, and control effectiveness for different flight conditions. The optimal main fiber direction is rotated forward of the front spar direction in the outer wing, leading to extension-shear coupling in the skins, which increases the washout behavior of the wing. Washout effects shift the lift forces inboard and allow skin thickness reductions, but also lead to reductions in aileron control effectiveness. The optimized tow-steered laminate configurations achieved larger mass reductions than optimized straight-fiber configurations.

Quantification of Ocular Biologically Effective UV Exposure for Different Rotation Angle Ranges Based on Data from a Manikin

Human outdoor activities are randomly orientated at different angles to the sun. To quantify the ocular UV and biologically effective UV (UVBE; i.e. the ocular UV irradiance exposure for photokeratitis (UVpker), photoconjunctivitis (UVpcon), and cataract (UVcat)) exposure for different rotation angle ranges, a rotating manikin was used to monitor the ocular UV exposure at different rotation angles in clear skies during July 2010 in Sanya, China. As a result, the ocular UV and UVBE irradiance was directly influenced by the rotation angle variations, primarily for the 120° rotation angle ranges facing the morning and afternoon sun when the solar elevation was lower than 60°; during these times, the UV and UVBE spectral irradiance decreased as the rotation angle increased. When compared to the 360° rotation angle ranges (which were considered to be the average exposure situation), the cumulative ocular UVBE for 60°, 120° and 180° rotation angle ranges were maximally 91% (UVcat), 94% (UVpker) and 121% (UVpcon); 71% (UVcat), 74% (UVpker) and 95% (UVpcon); 42%(UVcat), 45%(UVpker) and 55% (UVpcon) higher respectively. Meanwhile, the cumulative ocular UVBE for the 180° rotation angle ranges facing away from the sun were 46% (UVpker), 59% (UVpcon) and 45% (UVcat) lower.

SECOND HARMONIC GENERATION IN FERROELECTRIC LiTaO3 AND KNbO3 CONTAINING BULK NANO GLASS-CERAMICS

The precursor glasses in (mol%) 25.53Li2O-21.53Ta2O5-35.29SiO2-17.65Al2O3 (LTSA) and 25K2O-25Nb2O5-50SiO2 (KNS) glass systems were prepared by the melt-quench technique. Ferroelectric LiTaO3 (LT) and KNbO3 (KN) crystallites containing bulk nano glass-ceramics have been prepared by controlled crystallization of these precursor glasses respectively. Second harmonic generations (SHG) at 532 nm in both the glass-ceramics have been realized under fundamental beam of Nd3+ :YAG laser source (1064 nm). The SHG power output has been found to increase up to 14 and 62.4 nJ with variation of rotation angle for LT and KN bulk nano glass-ceramics respectively due to orientation of ferroelectric domains under applied field.

Simple method for measuring the high pretilt angle of nematic liquid crystals

Pretilt angle measurable by using the conventional crystal rotation method is limited to about 0°–20° and 70°–90°. We propose a method by which we can measure the pretilt angle by using the crystal rotation method even if the pretilt angle is between 20° and 70°. In this method, the determination of a pretilt angle is achieved by finding the rotation angles where transmittances are maximum and minimum in the periodic transmittance characteristics obtained with the variation of rotation angle.

Temporal correlations of earthquake focal mechanisms

We investigate the time–distance dependence of the 3‐D rotation angle, Φ, for pairs of focal mechanisms in the worldwide Harvard catalogue. We study the original catalogue as well as the subcatalogue with ‘well‐constrained’ earthquakes. Since the distribution of Φ is scale‐invariant (fractal) for small angles, the statistical analysis encounters serious difficulties due to the presence of outliers. We apply several statistical techniques to overcome this problem. To investigate the influence of errors in seismic moment inversion on the Φ angle distribution, we simulate errors to derive the bounds on possible rotation angle variations. We find that the random errors reported in the Harvard CMT catalogue explain only about one‐third of the difference in scalar moment and focal mechanism orientation when the Harvard moment tensor is compared to solutions in two other catalogues (USGS and ERI). This implies that systematic effects should be significantly larger than the random errors given in the Harvard solutions. Statistical analysis of the catalogue suggests that the rotation angle is less than 10°–12° for small time–distance intervals and increases with time difference between pairs of earthquakes, reaching 20°–25° for time intervals larger than 100 days for small distances. These results are important for predicting future earthquake activity and are relevant to modelling the stress influence on earthquake occurrence.