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In this work, we explored the growth regime of (100) β-Ga2O3 homoepitaxial films on substrates with different miscut angles (1°, 2°, and 4°) in the MOVPE system. Under a low O2/Ga ratio growth condition, step-flow growth of (100) β-Ga2O3 homoepitaxial films can be maintained up to 3 μm on substrates with different miscut angles. Moreover, the results reveal that the growth rate decreases slightly with decreasing miscut angles, which matches estimation of the Burton–Cabrera–Frank theory and can be explained by the model of adsorption–desorption. By comparing the miscut-dependent growth rates, we give experimental evidence on the fundamental difference between the growth of (100) β-Ga2O3 films by MOVPE and MBE. In addition, a transport model is proposed to explain the desorption process in terms of the boundary layer and the kinetic resistance. [ABSTRACT FROM AUTHOR]

In this article, we use spatially modulated control fields to increase the four-wave mixing efficiency in a four-subband semiconductor asymmetric double quantum well, motivated by similar works in atomic systems. Using a simplified version of the propagation equations, we show analytically that for control fields with a constant amplitude and linearly varying mixing angles with the propagation distance, a conversion efficiency close to unity can be achieved even for relatively short propagation distances. Subsequently, we confirm these results by numerically simulating the full set of propagation equations. [ABSTRACT FROM AUTHOR]

Purpose: To examine the influence of abutment emergence angle and abutment height on marginal periimplant bone stability in patients not considered susceptible to peri-implantitis. Furthermore, it was analyzed whether titanium-base (Ti-base) abutments lead to wider abutment emergence angles compared to one-piece abutments. Materials and Methods: A total of 48 abutments (ie, 24 Ti-base and 24 one-piece abutments in 24 patients) were evaluated at abutment installation, after 1 year, and thereafter on a yearly basis for up to 5 years. Clinical and radiographic outcome variables were assessed. Results: With regard to peri-implant marginal bone stability, only moderately negative, albeit significant, correlations were found on the mesial sides of the one-piece abutments after 4 and 5 years for an abutment emergence angle > 30 degrees. No statistically significant negative correlations were found for distances of ≤ 1.5 mm between the restoration margin and the crestal peri-implant bone level for either Ti-base or for one-piece abutments. Furthermore, abutments bonded to Ti-bases were not associated with larger emergence angles than one-piece abutments. Conclusions: For patients at low risk of developing peri-implantitis, it can be concluded that neither a larger abutment emergence angle (> 30 degrees) nor a distance of ≤ 1.5 mm between the restoration margin and the crestal peri-implant bone level are associated with marginal peri-implant bone loss. Furthermore, abutments bonded to Ti-bases are not associated with wider emergence angles than one-piece abutments. [ABSTRACT FROM AUTHOR]

The magnetic field B induced along the axis of symmetry of axially magnetized cones was studied analytically and experimentally for various cone angles α. An explicit algebraic equation was derived for sharp-pointed and truncated cones. A sharp cone is characterized by singularities of B and ∇ B at its apex point. For a truncated cone, the maximum values of these quantities are achieved for α m a x ∼ 54.7 ° and α ∇ ∼ 39.2 ° , respectively. Two truncated cones with α u n i ∼ 63.4 ° positioned in a mirrored co-apex configuration produce a uniform axial field in the free-space gap. For smaller angles, the minimum field is located in the center of the airgap, while for larger, it is at the cones' surfaces with extremum at α m i n ∼ 71.6 °. These predictions were investigated using a tunable apparatus in which Co–Fe cones are magnetized by cylindrical NdFeB magnets. Strong ∼ 4 T B-field was achieved. Experimental results are discussed in detail, including incomplete magnetization and other secondary effects. [ABSTRACT FROM AUTHOR]

Miniaturized light-emitting diodes (mini-LEDs) have gained much attention for liquid crystal displays back-light and self-emissive displays. However, the unsatisfactory performance of InGaN long-wavelength mini-LEDs hinders their practical applications. Herein, we develop a full-angle distributed Bragg reflector (DBR) and investigate its impact on the performance of yellow flip-chip mini-LEDs. The full-angle DBR consists of different stacks of Ti3O5/SiO2 layers that are optimized for multiple central wavelengths. Compared to conventional single-DBR stacks, such full-angle DBR enables wider reflectance bandwidth and less dependence of reflectance on the light incident angle from 0° to 50°. Specifically, full-angle DBR features high reflectance beyond 99% from 447 to 580 nm at an incident angle of 50°. Full-angle DBR is found to enhance the electric field intensity at the top of devices, indicating that light extraction efficiency is promoted. As a result, yellow flip-chip mini-LEDs with full-angle DBR show higher light output power than those without DBR at the same currents. Our work paves a way to improve the performance of small-size emitters with long wavelength. [ABSTRACT FROM AUTHOR]

The coupling between the symmetric (νs) and antisymmetric (νa) OD stretch modes of monomeric D2O in CHCl3 is investigated using polarization-dependent two-dimensional infrared (2D IR) spectroscopy supported by numerical 2D IR simulations based on the exciton-band theory. The relationship between the local modes' and the exciton states' parameters is systematically studied, including center frequencies, diagonal anharmonicities, coupling, and off-diagonal anharmonicity. The mean coupling between νs and νa is accurately evaluated to be −49.96 ± 0.14 cm−1. The degree of relaxation in the harmonic approximation is quantified, and the angle between the exciton-state dipoles is accurately evaluated to be 101.4° ± 3.6°. In addition, the effect of the local-mode frequency correlation on the resulting exciton-state frequency correlation and the spectral shape of the linear and 2D IR spectra are also investigated. [ABSTRACT FROM AUTHOR]

Spintronic devices would greatly benefit from a noncollinear alignment between magnetizations of adjacent ferromagnetic layers for maximum performance and reliability. We demonstrate that such an alignment can be created and controlled by coupling two ferromagnetic layers across a magnetic spacer layer consisting of a nonmagnetic material, Ru, alloyed with a ferromagnetic element, Co. Changing the composition and thickness of the spacer layer enables the control of the relative angle between the magnetizations of the ferromagnetic layers between 0 ° and 180 °. The onset of noncollinear alignment between the ferromagnetic layers coincides with the advent of magnetic order in the spacer layer. This study maps the concentration and thickness ranges of RuCo spacer layers that give rise to noncollinearity between ferromagnetic Co layers. The experimental results are successfully reproduced by simulating our structures with an atomistic model. This model assumes that Co atoms in the RuCo spacer layer have magnetic moments and that neighboring Co atoms are ferromagnetically coupled, while Co atoms separated by one or more Ru atoms are antiferromagnetically coupled. [ABSTRACT FROM AUTHOR]

Polymer-dispersed liquid crystal (PDLC) film is an electrically controlled dimming film in which the orientation of the liquid crystal molecules can be changed by applying an electric field. When the liquid crystals are perpendicular to the PDLC film, the film is transparent. Birefringence occurs after light passes through the liquid crystal molecules, resulting in two beams of light with perpendicular vibration directions. Therefore, PDLC film appears hazy when viewed from the side. In this study, a polarizing film was introduced to reduce the side-view haze, and its influence on the haze at different angles and positions was investigated. Experiment results revealed that aligning the PDLC film along the polarizing film's absorption axis reduced the haze at all angles. When the polarizing film was attached to each side of the PDLC film and the absorption axis angle of the films was 0∘, a wide-viewing-angle PDLC film was obtained; at a 45∘ tilt, the haze only increased by 0.33%, and at 60∘ it maintained a clear field of view. This may be because only light in the same direction as the absorption axis passed through the film, reducing the amount of light that did not match the polymer refractive index. [ABSTRACT FROM AUTHOR]

Summary: LEDs are a prominent technique for a pervasive communication system using visible light communication (VLC), since LED includes long life expectancy, fast switching, and being visible light and is less expensive, which is safe for the human body, though still many technical problems presented to be addressed, especially in an indoor environment. Due to this, the major aim of this task is to afford a hybridized optimization algorithm that is highly suitable for enabling the signal to noise ratio (SNR) and received signal strength (RSS) maximization in VLC. Here, the coordinate of each point of the receiver photo detector in the VLC system is tuned by the new hybridized algorithm. The fusion of two optimization algorithms like Deer Hunting Optimization Algorithm (DHOA) and Dragonfly Algorithm (DA) termed as Fitness‐oriented Dragonfly‐based DHOA (FD‐DHOA) is used to attain the objective concerning the RSS or received power and SNR. The proposed model tries to attain maximum RSS and SNR at the receiver instead of calculating it at every angle. Moreover, the experimental analysis proves that the developed model validates the orientation that generates an optimum RSS and SNR value at the receiver. [ABSTRACT FROM AUTHOR]

To improve the uniformities of the flow distributions in radial beds, different design methods for conical channels were developed, that is, proportional method, traditional linear method for minimizing the pressure difference between two ends of the channel, newly proposed improved linear method for minimizing the pressure axial variation in the whole channel, and improved multi-segment linear method that divide the channel into multi-segments with different inclination angles. The flow fields under different design methods and gas flow rates are then investigated by numerical simulation. The designation of the angle of the conical channel is particularly significant. Compared to the original structure, the proportional method has difficulty obtaining a proper inclination angle, whose inhomogeneity indices of the distributions of pressure drop ηp and gas velocity ηv may increase or decrease. The traditional linear method has lower inhomogeneity indices, for example, ηv will decrease by ≥7.02%, which denotes more uniform flow distributions, while the improved linear and multi-stage linear methods have the lowest inhomogeneity indices, for example, ηv will decrease by ≥12.12 and 13.60%, respectively. Besides, the latter two methods have good adaptability and robustness to fluctuations in the gas flow rate. Two new design methods of conical channel are proposed. Inhomogeneity indices are introduced to quantify the uniformity of flow distribution. Robustness of different design methods are evaluated. [ABSTRACT FROM AUTHOR]

Rockfall frequently occurs in the mountainous areas and threatens structures such as settlement areas, transportation lines, and agricultural field. The empirical approaches for rockfall mapping have been an attractive research topic in rock mechanics in the recent years, because producing rockfall maps of large areas by using the deterministic and the probabilistic analysis seems difficult due to the necessity of numerous inputs. The cone propagation approach is preferred as a practical tool particularly in the regional scale. The digital elevation model (DEM) of a region prone to rockfall is used for determination of possible propagation zones based on a simple geometric rule known as the energy line angle (reach angle). As a new term, ELAmax_stop was defined to represent the energy line angle that extends to the border of the propagation zone as the maximum run-out distance that is obtained from application of the cone approach to all points (pixels) in source area. The angle denoted as α refers to the threshold slope angle of the steep areas utilized to identify potential source areas by using DEM. Conceptually, the fallen rock blocks within a rockfall-prone region stop within the cone propagation zone, which is bounded by the energy line angles α and ELAmax_stop. While the value of α is susceptible to the resolution of DEM, ELAmax_stop, which exhibits a wide angle range as documented in the literature, is controlled by rock block features together with slope surface properties of the propagation zone. Due to the variability of ELAmax_stop and α depending on the studied region and the resolution of the DEM, the boundary value of the energy line angles between different susceptibility classes need to be adjusted by considering α and ELAmax_stop. By adopting the cone propagation approach to enable adjustable use of energy line angles for rockfall susceptibility mapping, a series of graphical presentations was prepared. These graphical presentations allowed for the prediction of energy line angles corresponding to various rockfall susceptibility classes including very low, low, medium, high, and very high. In addition to the graphical presentations, a series of practical equations were derived for the same purpose. In the final part of the study, a new rating system, namely the run-out distance rating (RDR), was introduced for the preliminary determination of ELAmax_stop. Due to the empirical structure of the methodology, the suggested supportive approach to the practitioners for determining ELAmax_stop should be considered as an initial step that opens to improvement. The proposed methodology in this study was implemented in the regions of Kargabedir Hill and Sivrihisar residential areas in Turkey to prepare rockfall susceptibility maps. [ABSTRACT FROM AUTHOR]

For a convex lattice polytope P ⊂ R d of dimension d with vertices in Z d , denote by L(P) its discrete volume which is defined as the number of integer points inside P. The classical Ehrhart theorem states that given a positive integer n, the function L(nP) is a polynomial in n of degree d, whose leading coefficient is the volume of P. In particular, L(nP) approximates the volume of nP for large n. In convex geometry, one of the central notions generalizing the volume is the intrinsic volume. The main goal of the present paper is to introduce its discrete counterpart. In particular, it is proved that an analog of the Ehrhart theorem where volume is replaced by intrinsic volume holds true for it. A notion of Grassmann angle valuation generalizing both discrete volume and the solid-angle valuation introduced by Reeve and Macdonald is also introduced and studied. [ABSTRACT FROM AUTHOR]

Heat‐shrinkable films commonly serve as active materials for self‐folding owing to their capability to fold all hinges upon heating. For origami‐based electronic devices, the self‐folding of the metal layer is necessary. Nevertheless, the self‐folding angle is low owing to the high bending stiffness of metal layers and the low adhesion of heat‐shrinkable films. Here, we introduce a bilayer self‐folding technique that effectively suppresses delamination of the shrink layer, thereby achieving a high folding force and angle. A polyolefin film mechanically fixed on the metal substrate serves to inhibit delamination, regardless of the adhesive properties of the shrink layer. This is achieved by applying adhesives within holes fabricated on the shrink layer. Conventional methods using an adhesive layer to fix the shrink layer lead to delamination at temperatures above 100°C, resulting in a decrease in self‐folding angles. In contrast, our novel fixing method yields a folding angle of 161° at 140°C, with a shrinkage rate of 69%. To demonstrate the versatility of our proposed technique, we self‐fold various origami structures, including Miura‐ori, scissors, cranes, and tessellation with chip LEDs. The introduced method broadens the range of substrate materials suitable for self‐folding and offers new possibilities for the development of origami devices. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Objectives: Estimating the sex of cremated human remains is difficult. The petrous bone frequently survives the cremation due to its density. Wahl observed the lateral angle to be sexually dimorphic in the 1980s. Previous studies showed various cut‐off points to separate females from males, which are hardly replicable and difficult to apply. We want to test the Wahl method and compare it to a new landmark‐based version. Materials and Methods: In this study, we measured the lateral angle of 35 cremated petrous bones from late bronze age Austria using micro‐CT scans. Technical errors of measurement were calculated for two different methods to intersect the internal acoustic meatus virtually in the midline (manual or landmark‐based intersection). Furthermore, sex was estimated based on morphological features and metric measurements. This information was used in logistic regression modeling to define a cut‐off point in our sample. Results: The technical errors of measurement suggested that a landmark‐based method was more precise in comparison to a manual intersection which was much more intuitive. Inter‐ and intra‐observer errors were low which improved reliability. The logistic regression model produced good results in our sample (p = 0.02, R2 = 0.38, accuracy = 0.8). The mean lateral angle was similar to studies which focused on prehistoric cremated petrous bones. Discussion: The proposed landmark‐based method was precise, quick, and could be easily applied, even by unexperienced researchers. The size of the lateral angle seemed to be population‐specific but also dependent on the method applied. We recommend to use the proposed landmark‐based method which is more precise. [ABSTRACT FROM AUTHOR]

More accurate inversion of source fault geometry and slip parameters under the constraint of the Bayesian algorithm has become a research hotspot in the field of geodetic inversion in recent years. In nonlinear inversion, the determination of the weight ratio of the joint inversion of multisource data is more complicated. In this context, this paper proposes a simple and easily generalized weighting method for inversion of source fault parameters by joint geodetic multisource data under the Bayesian framework. This method determines the relative weight ratio of multisource data by root mean square error (RMSE) value and can be extended to other nonlinear search algorithms. To verify the validity of the method in this paper, this paper first sets up four sets of simulated seismic experiment schemes. The inversion results show that the joint inversion weighting method proposed in this paper has a significant decrease in the large residual value compared with the equal weight joint inversion and the single data source joint inversion method. The east–west deformation RMSE is 0.1458 mm, the north–south deformation RMSE is 0.2119 mm and the vertical deformation RMSE is 0.2756 mm. The RMSEs of the three directions are lower than those of other schemes, indicating that the proposed method is suitable for the joint inversion of source parameters under Bayesian algorithm. To further verify the applicability of the proposed method in complex earthquakes, the source parameters of the Maduo earthquake were inverted using the method of this paper. The focal depth of the inversion results in this paper is closer to the focal depth released by the GCMT agency. In terms of strike angle and dip angle, the joint inversion in this paper is also more inclined to the GCMT results. The joint inversion results generally conform to the characteristics of left-lateral strike-slip, which shows the adaptability of this method in complex earthquakes. [ABSTRACT FROM AUTHOR]

Gait recognition is one of the most promising video-based biometric technologies. The edge of silhouettes and motion are the most informative feature and previous studies have explored them separately and achieved notable results. However, due to occlusions and variations in viewing angles, their gait recognition performance is often affected by the predefined spatial segmentation strategy. Moreover, traditional temporal pooling usually neglects distinctive temporal information in gait. To address the aforementioned issues, we propose a novel gait recognition framework, denoted as GaitASMS, which can effectively extract the adaptive structured spatial representations and naturally aggregate the multi-scale temporal information. The Adaptive Structured Representation Extraction Module (ASRE) separates the edge of silhouettes by using the adaptive edge mask and maximizes the representation in semantic latent space. Moreover, the Multi-Scale Temporal Aggregation Module (MSTA) achieves effective modeling of long-short-range temporal information by temporally aggregated structure. Furthermore, we propose a new data augmentation, denoted random mask, to enrich the sample space of long-term occlusion and enhance the generalization of the model. Extensive experiments conducted on two datasets demonstrate the competitive advantage of proposed method, especially in complex scenes, i.e., BG and CL. On the CASIA-B dataset, GaitASMS achieves the average accuracy of 93.5% and outperforms the baseline on rank-1 accuracies by 3.4% and 6.3%, respectively, in BG and CL. The ablation experiments demonstrate the effectiveness of ASRE and MSTA. The source code is available at https://github.com/YanSun-github/GaitASMS. [ABSTRACT FROM AUTHOR]

This paper investigates the issue of integrated guidance and control (IGC) design for an unmanned aerial vehicle with an unknown control coefficient, approach angle constraint, and field-of-view limitations. Different from the existing methods, the proposed approach integrates the approach angle and field-of-view requirements into a single reference to satisfy the constraints simultaneously, and meanwhile guarantees the successful mission despite the unknown control coefficient. Based on the established IGC model, a novel sliding mode strategy is generated to ensure that the approach angle and field-of-view constraints can be obeyed once the designed reference is tracked precisely. Then, the IGC issue are transformed into a tracking problem under an unknown control direction, and the periodic sliding mode control technique is introduced to construct the IGC law. The stability of the closed-loop system is analyzed in detail. The effectiveness of the proposed method is verified by numerical simulations. [ABSTRACT FROM AUTHOR]

This study presents a new solution algorithm to calculate the bearing capacity coefficient Nγ for a fully rough strip footing located on an infinite slope considering different soil friction angles φ and ground slopes β° using the stress characteristics method. The results showed that Nγ coefficients decreased with an increase in slope inclination, and roughness contribution prevented further reduction, particularly for higher φ values. The higher contribution of the upside-sloping ground for footing laid on the infinite slope led to a lower reduction of the Nγ coefficients compared with the footing placed at the slope vicinity in terms of a larger area affected by the stress field, and a larger plastic region of the downface slope. The reduction value was more eminent for steeper slopes β ≥ 20° due to the tendency for nonsymmetrical failure pattern, especially for higher φ values. The findings of the current research and those described in the literature were in good agreement, so much so that the lower-bound limit analysis and the current solution technique virtually reflect the same trend. The load inclination values for footings located adjacent to the slope with β ≤ 30° were not meaningful, whereas for footing resting on an infinite slope with β ≥ 25° it exceeds 15°, which reflects the fact that its effect should not be neglected, especially for ground slopes greater than 20°. By increasing β°, the maximum values of plastic length and plastic depth on the left and right sides of the footing decrease and increase, respectively. The maximum depth of the plastic region for β ≥ 20° from around the right side of the footing shifts toward the downward-sloping face. The maximum width of the elastic wedge gradually reduces, and the intersection point of the left and right plastic regions slowly shifts to the left and upside of the footing. [ABSTRACT FROM AUTHOR]

Objective: The present work explores how the horizontal viewing angle of a virtual character's face influences perceptions of credibility and approachability. Background: When encountering virtual characters, people rely both on credibility and approachability judgments to form a first impression of the depicted virtual character. Research shows that certain perceptions are preferred either on frontal or tilted faces, but not how approachability or credibility judgments relate to horizontal viewing angles in finer granularity between 0° and 45°. Method: 52 participants performed a two-alternative forced choice (2AFC) task rating 240 pairwise comparisons of 20 virtual character faces shown in four horizontal viewing angles (0°, 15°, 30°, and 45°) on approachability and credibility. They also rated scales on individual differences based on the BIS-BAS framework (behavioral inhibition system, drive, and reward responsiveness), self-esteem, and personality traits (neuroticism, loneliness). Results: Both approachability and credibility were negatively related to the horizontal viewing angle, but the negative relationship was less pronounced for approachability. Notably, 15° tilted faces were associated with higher approachability than frontal faces by people scoring high in reward responsiveness, drive, and self-esteem, and scoring low in neuroticism and loneliness. Conclusion: Our findings highlight the conditions under which showing a virtual character's face is preferred in a horizontally 15° tilted over a frontal position. Application: The differential impact of the horizontal viewing angle on approachability and credibility should be considered when displaying virtual character faces. [ABSTRACT FROM AUTHOR]

Scoliosis is a spinal deformation in which the spine takes a lateral curvature, generating an angle in the coronal plane. The conventional method for detecting scoliosis is measurement of the Cobb angle in spine images obtained by anterior X-ray scanning. Ultrasound imaging of the spine is found to be less ionising than traditional radiographic modalities. For posterior ultrasound scanning, alternate indices of the spinous process angle (SPA) and ultrasound curve angle (UCA) were developed and have proven comparable to those of the traditional Cobb angle. In SPA, the measurements are made using the spinous processes as an anatomical reference, leading to an underestimation of the traditionally used Cobb angles. Alternatively, in UCA, more lateral features of the spine are employed for measurement of the main thoracic and thoracolumbar angles; however, clear identification of bony features is required. The current practice of UCA angle measurement is manual. This research attempts to automate the process so that the errors related to human intervention can be avoided and the scalability of ultrasound scoliosis diagnosis can be improved. The key objective is to develop an automatic scoliosis diagnosis system using 3-D ultrasound imaging. The novel diagnosis system is a three-step process: (i) finding the ultrasound spine image with the most visible lateral features using the convolutional RankNet algorithm; (ii) segmenting the bony features from the noisy ultrasound images using joint spine segmentation and noise removal; and (iii) calculating the UCA automatically using a newly developed centroid pairing and inscribed rectangle slope method. The proposed method was evaluated on 109 patients with scoliosis of different severity. The results obtained had a good correlation with manually measured UCAs ( R 2 = 0.9784 for the main thoracic angle and R 2 = 0.9671 for the thoracolumbar angle) and a clinically acceptable mean absolute difference of the main thoracic angle (2.82 ± 2.67°) and thoracolumbar angle (3.34 ± 2.83°). The proposed method establishes a very promising approach for enabling the applications of economic 3-D ultrasound volume projection imaging for mass screening of scoliosis. [ABSTRACT FROM AUTHOR]

Basal plane dislocations (BPDs) in 4H-SiC are the main reason for the degradation of bipolar devices. In the experiment, the distribution of 4-fold symmetry BPDs is observed in the etch pit density of the 4H-SiC wafer, which is inconsistent with the phenomenon of the distribution of 6-fold symmetry BPDs because of the hexagonal structure of 4H-SiC. To explain the distribution of 4-fold symmetry BPDs in the grown crystal, 3D modeling of BPDs in 4H-SiC crystals grown by the PVT method has been performed. The results show that the adoption of 4-degree off-axis seed crystals that are widely used in the industry caused the distribution of 4-fold symmetry BPDs. Moreover, the distribution of BPDs is 6-fold symmetry in on-axis grown 4H-SiC single crystals; with the increase of the off-angle, the distribution of BPDs gradually changes from 6-fold to 4-fold symmetry, and the maximum value of the BPD density is at the periphery. In the end, the strategy of growing 4H-SiC crystals with large-size seed crystals has been proposed to reduce the BPD density in the wafer and improve the quality of the substrate. The calculation results shows that the use of 220 mm seed crystals can reduce the BPD density by 15% compared with 200 mm seed crystals. [ABSTRACT FROM AUTHOR]

By treating KSiiPr3 with Sn[N(SiMe3)2]2 the distannene Sn2(TIPS)4 (TIPS=SiiPr3) is formed in a metathesis reaction. The crystal structure analysis of Sn2(TIPS)4 reveals a planar arrangement of the substituents in the solid‐state and hence the second planar alkene like distannene of its kind. Due to the TIPS substituents, Sn2(TIPS)4 is well soluble in all commonly used organic solvents, opening the door for various analytics and reactivity studies. Due to its stability in solution, various reactions can be performed such as cycloaddition reactions with 2,3‐dimethyl‐1,3‐butadiene (DMBD) and TMS‐azide. [ABSTRACT FROM AUTHOR]

The effect of inside surface baffle installation conditions on the minimum impeller rotational speed for just the drawdown of floating solid N JD was investigated. The inside surface baffle condition is the condition in which a partial baffle is placed with a clearance between the baffle and the vessel wall. In this study, a baffle with an insertion length of 0.2 times the liquid height was used. Moreover, the effect of baffle angle on N JD was investigated. The N JD was measured visually at least three times. The results showed that the effect of the radial installation position of the inside surface baffle on N JD depended on the impeller position. In addition, even baffles placed parallel to the tangential flow were found to decrease N JD . [ABSTRACT FROM AUTHOR]

The distance effect (comparing objects becomes easier with increasing differences in their magnitude) is observed in tasks ranging across domains, and its existence has been interpreted as evidence for analogue magnitude representation. Similarly, associations between response side and magnitude (faster left/right-sided responses to small/large objects, respectively) are observed across domains. We investigated the analogue processing of angles and the association between angle magnitude and response side in relation to geometric expertise. We compared the behavioural pattern of two groups—architects and controls—in a direct angle magnitude classification task (i.e., judge whether a presented angle was greater or less than 90°) and in an indirect task (i.e., judge whether an angle was drawn with a dashed or continuous line). We found a robust distance effect for reaction times and accuracy at the whole sample level and in each group separately. Architects revealed a smaller distance effect for accuracy than controls. This could be interpreted as an argument for a more precise analogue representation of angles in experts compared to non-experts. However, we did not find evidence for an association between angle magnitude and response side in any group. [ABSTRACT FROM AUTHOR]

The new thermal insulating shotcrete is of great significance for the management of thermal damage in deep mines, and its own strength has a greater impact on the roadway insulation and safe production, so it is very necessary to study the shear strength of the new thermal insulating shotcrete under the influence of the deep hot and humid environment and the stress of mining. For the heat-insulating shotcrete, firstly, we carried out the concrete variable angle shear test under different loading rates, which concluded that the shear rate and peak shear stress showed a trend of increasing and then decreasing; as the angle increases, the different rates have a greater impact on the peak shear stress of the specimen. Secondly, the concrete variable angle shear test was carried out under the temperature and humidity cycle, which revealed that the shear strength of thermal insulated shotcrete increased firstly and then decreased with the increase of temperature at the same number of cycles. Finally, the empirical equations between the cohesive force c, the angle of internal friction ϕ and the number of warm and wet cycles n and the temperature of warm and wet cycles T are fitted with the MATLAB software respectively, and the research results provide technical references for the management of geothermal temperature in deep well projects. [ABSTRACT FROM AUTHOR]

Some passive sensors can provide only relative angles of a signal source. To obtain the signal source location, multiple passive sensors can be constructed into a passive sensor network through communication links. This paper investigates the source localization problem with angle-only measurements in three-dimensional space. First, we present an intersection localization method, which estimates the target position by minimizing the sum of distances between lines formed by angle-only measurements. It has the same target position estimate as the widely used least-squares (LS) method, but with a lower computational cost. Furthermore, considering the differences in measurement accuracy of sensors, the weighted least-squares (WLS) algorithm can achieve better localization performance than the LS method. Unfortunately, since the coefficient matrix and the noise vector are correlated, the WLS method is biased. The bias-compensation WLS (BCWLS) method is also presented in this paper to reduce the bias by estimating the correlation between the coefficient matrix and the pseudolinear noise vector. To evaluate the performance of the presented algorithms, numerical simulations are conducted, indicating that the superiority of the intersection localization method in computational cost and the superiority of the BCWLS method in localization accuracy. [ABSTRACT FROM AUTHOR]

This article introduces a spatial angle measuring device based on ensemble diamond nitrogen–vacancy (NV) center optical detection magnetic resonance (ODMR). This device realizes solid-state all-optical wide-field vector magnetic field measurements for solving the angles of magnetic components in space. The system uses diamond NV center magnetic microscope imaging to obtain magnetic vector distribution and calculates the spatial angles of magnetic components based on the magnetic vector distribution. Utilizing magnetism for angle measuring enables non-contact measuring, reduces the impact on the object being measured, and ensures measurement precision and accuracy. Finally, the accuracy of the system is verified by comparing the measurement results with the set values of the angle displacement platform. The results show that the measurement error of the yaw angle of the system is 1°, and the pitch angle and roll angle are 1.5°. The experimental results are in good agreement with the expected results. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) clinical gait analysis systems are more affordable and portable than contemporary three-dimensional (3D) clinical models. Using the Vicon 3D motion capture system as the standard, we evaluated the internal statistics of the Imasen and open-source OpenPose gait measurement systems, both designed for 2D input, to validate their output based on the similarity of results and the legitimacy of their inner statistical processes. We measured time factors, distance factors, and joint angles of the hip and knee joints in the sagittal plane while varying speeds and gaits during level walking in three in-person walking experiments under normal, maximum-speed, and tandem scenarios. The intraclass correlation coefficients of the 2D models were greater than 0.769 for all gait parameters compared with those of Vicon, except for some knee joint angles. The relative agreement was excellent for the time–distance gait parameter and moderate-to-excellent for each gait motion contraction range, except for hip joint angles. The time–distance gait parameter was high for Cronbach's alpha coefficients of 0.899–0.993 but low for 0.298–0.971. Correlation coefficients were greater than 0.571 for time–distance gait parameters but lower for joint angle parameters, particularly hip joint angles. Our study elucidates areas in which to improve 2D models for their widespread clinical application. [ABSTRACT FROM AUTHOR]

The transmission towers served as crucial carriers in the process of power transmission. The combined angle transmission tower of dual-angle steel with cruciform section are relatively a novel type of angle tower, which is being more widely used in transmission lines. The studies on aerodynamic characteristics of combined angle tower in skewed wind are limited. In this paper, the wind tunnel tests are conducted to investigate the aerodynamic characteristics of the combined angle tower, and the high frequency force balance (HFFB) test is introduced to obtain the transverse and longitudinal forces on the tower using the direct force measurement (DFM) method. The drag coefficients and wind load-distribution factors of the combined angle tower are obtained from the wind tunnel tests, and the effects of interference and tower leg spacing on the wind loads of the tower legs are fully explored. It can be found that the aerodynamic coefficients and drag coefficients of the combined angle steel tower leg tend to decrease with the increase of interference members and it also decreases with the decrease of the tower leg spacing. The test wind load-distribution factors of the isolated leg are generally larger than those defined by seven typical codes (e.g., US, EU, Japanese, and Chinese codes) and significantly exceed the code-specified values under partial wind angles. The observations obtained from this study may provide helpful guidance on the wind-resistant design of this relatively novel type of combined angle tower. [ABSTRACT FROM AUTHOR]

This article develops the fundamentals of the tip position control of flexible single‐link robotic manipulators in the frequency domain without approximating the model. Analytic transfer functions of the hub angle and tip position are derived without any model order reduction. Conditions for the stability of the transfer functions are presented by considering the payload mass change as an uncertain parameter. Using the D‐decomposition method, a simple procedure is introduced to design an output feedback controller which guarantees the stability and a desired tracking performance. The introduced design method leads to less conservatism comparing with design methods established upon model reduction. The controller structure includes two proportional‐derivative and integral loops and needs only two measurements of joint angle and tip position which are easily implementable. A numerical example is provided to demonstrate the merit of the achieved results. [ABSTRACT FROM AUTHOR]

Ignition electrodes have an immense impact on the accurate measurement of the flame propagation spherical radius. In this study, a flame-radius calculation method is designed. The method is able to eliminate effects due to the ignition electrodes. The adaptability and optimization effects of the proposed method are analyzed. The results show that the ratio of the angle is affected by the ignition electrodes under the Han II method. There are three obvious divisions include a high-value area, a sharp-variation area, and a mild-variation area. The ratio of the angle affected by the ignition electrodes is only applicable to the mild-variation region when the flame presents respective convex and concave distributions. For these distributions, the increment rate of the mean radius is 0.4–0.85% and 0.42–3.19%. The reduced rate of the standard deviation of the radius extraction value is 11.91–22.1% and 5.13–17.99%, and the reduced rate of the radius extraction value range is 20.32–39.51% and 0.32–8.09%. [ABSTRACT FROM AUTHOR]

Ductile materials exhibit rate-dependent behaviors when subjected to different loading rates, particularly during impact and explosion events. In order to investigate the high strain rate behaviors of metal materials, a phase field model considered the rate-dependent threshold for effective plastic work is proposed. And the presented model couples the influences of the stress triaxiality and Lode angle parameter on failure behaviors. Later, a single element is modeled to demonstrate the impacts of the model in predicting stress-strain relations under varying loading rates. To illustrate the impacts of the Lode angle parameter on load-displacement responses, rectangular notch specimens are used. Next, the presented model is employed to mimic the shear fracture of hat-shaped specimens at different strain rates based on the split Hopkinson pressure bar tests, and the model parameters are calibrated by comparing the strain waveforms between the simulations and experiments. The numerical results indicate the developed model is capable of accurately reproducing the shear ductile fracture of the hat-shaped specimens under high strain rates. [ABSTRACT FROM AUTHOR]

Purpose: To objectively quantify glare of intraocular lenses (IOLs) using a diffractive principle to extend the visual range and to identify models with increased susceptibility to inducing glare. Setting: David J Apple Laboratory, Heidelberg, Germany. Design: Laboratory investigation. Methods: Glare was assessed by means of a straylight parameter with a standard C-Quant intended for 7 degrees. In addition, 2 C-Quant modifications were used to test lower angles (ie, 2.5 degrees and 3.5 degrees). The following IOLmodels were assessed: PanOptix, AT Lisa Tri, Synergy, and Triumf, the latter 2 with chromatic aberration correction at distance. Straylight from trifocal IOLs was compared against a monofocal W-60R lens. The C-Quant test was performed through the studied IOLs by using additional optical components attached to their ocular. Results: Straylight (deg2sr-1) of the control was <1 at all tested angles, with the trifocal models showing comparable straylight at 7 degrees. At 3.5 degrees, Triumf's straylight increased to 15.5 ± 0.6, followed by Synergy (6.2 ± 1.1), PanOptix (4.1 ± 0.3), and AT Lisa Tri (2.0 ± 0.8). The chromatic aberration-correctingmodels demonstrated correspondingly higher straylight (Synergy: 18.8 ± 1.3; Triumf: 17.3 ± 0.5) at 2.5 degrees compared with PanOptix (4.3 ± 0.4), AT Lisa Tri (2.1 ± 0.1), and monofocal IOLs yielding minimal or no increase. Conclusions: Trifocal IOLs induced increased straylight, but it was limited to lower angles, which may cause difficulties detecting these effects using a standard clinical approach. The latest IOLdesigns featuring chromatic aberration correction at far focus seem more susceptible than the established trifocal IOLs to inducing a glare phenomenon. [ABSTRACT FROM AUTHOR]

Chatter causes great damage to the machining process, and the selection of appropriate process parameters through chatter stability analysis is of great significance for achieving chatter-free machining. This article proposes a milling stability analysis method based on the barycentric rational interpolation differential quadrature method (DQM). The dynamics of the milling process considering the regeneration effect is first modelled as a time-delay differential equation (DDE). When adjacent pitch angles of the milling cutter are symmetric, the milling dynamic equation contains a single time delay. Otherwise, when adjacent pitch angles are asymmetric, the dynamic equation contains multiple time delays. The barycentric rational interpolation DQM is then used to approximate the differential and delay terms of the milling dynamics equation, and to construct a state transition matrix between adjacent milling periods. Finally, the chatter stability lobe diagram (SLD) is obtained based on the Floquet theory. According to the SLD, the appropriate spindle speed can be selected to obtain the maximum stable axial depth of cutting, thereby effectively improving the material removal rate. The accuracy and efficiency of the proposed method have been validated by two widely used milling models, and the results show that the proposed method has good accuracy and computational efficiency. [ABSTRACT FROM AUTHOR]

The assortment of low-cost 3D printers for "in-practice" use, e.g., for clear aligner therapies, is ever increasing. To address concerns about the accuracy of orthodontic models produced on such printers when cost-efficient modes of 3D printing are employed, this study examined the effect of print model body type and print angulation on accuracy. Six printing-configuration groups were included: two model types (solid or hollow shell) combined with three print angles (0°, 70°, or 90°) with 10 models/group; all models were printed with 100 µm layer thickness using a digital light processing-based three-dimensional printer. Eleven selected structures and distances were measured on the printed models with a digital microscope and compared to the same measures on a digitized master model. The clinically acceptable range was set at ±0.25 mm difference from the master model for single tooth measurements (intra-tooth) and ±0.5 mm for cross-arch measurements (inter-tooth). For individual measurements across all models, 98% fell within clinical acceptability. For mean measurements within each model group, only canine height for the shell-0° model had a mean difference (−0.26 mm ± 0.03) outside the clinically acceptable range for intra-tooth measurements. Standard deviations for all intra-tooth measurements were within 0.07 mm. While none of the mean inter-tooth measurements exceeded the acceptability range, the standard deviations were larger (0.04 to 0.30 mm). The accuracy of the orthodontic models for clear aligner therapies was not impacted beyond the clinically acceptable range when altering model body type and print angulation to improve efficiency of 3D printing. These findings suggest greater flexibility of the practitioner to alter print settings to address time and cost efficiency in various clinical scenarios and still maintain clinically acceptable model accuracy. [ABSTRACT FROM AUTHOR]

In order to explore the influence of dip angles on the deformation and failure of a coal–rock combination, uniaxial compression experiments were carried out on a coal–rock combination with different dip angles, and the acoustic emissions (hereinafter referred to as AE) responses during loading were collected. Based on the damage mechanics theory and fractal theory, the fractal dimensions of different damage degrees were calculated. The results show that, with the increase in the inclination angle, the compressive strength and elastic modulus of the coal–rock combination gradually decreased, while the AE ringing count gradually increased first and then decreased. At the initial loading stage of the specimen, the greater the damage degree of the coal–rock combination under the same strain condition, the larger the value of its overall fractal dimension. The AE fractal dimension of the coal–rock combination increases gradually between 10% and 20% of the damage degree. It suddenly decreased between 50% and 60%, then increased slightly before gradually decreasing to the minimum between 80% and 100%. The sudden decrease in fractal dimension, a slight increase, and then a continuous decrease can be used as the precursor information for the instability and failure of the coal–rock combination. [ABSTRACT FROM AUTHOR]

A limit plasticity solution for evaluating the effective stress friction angle in clays from piezocone tests was assessed and compared with the popular notion of using laboratory Atterberg limits on remoulded specimens. The results showed that the in situ piezocone-based method provided a far more accurate and robust interpretation of the friction angle values of 155 separate clays than empirical correlations with plasticity index when compared with laboratory benchmark values obtained from triaxial compression tests. For illustration, the piezocone-based method was shown successfully to capture the effective stress parameter of four clays with friction angles of 20–37°: normally consolidated kaolin clay in chamber tests; natural soft clay deposit located at Bothkennar, UK; Troll offshore clay in the North Sea; and soft plastic lacustrine deposits in Bogota, Colombia. [ABSTRACT FROM AUTHOR]

This paper discusses using ground-based imagery to determine the attitude of a flying projectile assuming prior knowledge of its external geometry. It presents a segmentation-based approach to follow the object and evaluates it quantitatively with simulated data and qualitatively with both simulated and real data. Two experimental cases are considered: One assumes reliable target distance measurement from an auxiliary range sensor, while the other assumes no range information. The results show that in the case of an unknown projectile–camera distance, with projectile dimensions of 1.378 m and 0.08 m in length and diameter, the estimated distance, in-plane location, and pitch angle accuracies are about 50 m, 0.15 m, and 6 degrees, respectively. Yaw angle estimation is ambiguous. In the second case, assuming that the projectile–camera distance is known resolves the ambiguity of yaw estimation, resulting in accuracies of about 0.15 m, 3 degrees, and 20 degrees for in-plane location, pitch, and yaw angles, respectively. These accuracies were normalized to a 1-km projectile–camera distance. [ABSTRACT FROM AUTHOR]

Back pain is regularly associated with biomechanical changes in the spine. The traditional methods to assess spine biomechanics use ionising radiation. Vertebral Metrics (VM) is a non-invasive instrument developed by the authors in previous research that assesses the spinous processes' position. However, the spine model used by VM is not accurate. To overcome it, the present paper proposes a pioneering and simple articulated model of the spine built through the data collected by VM. The model is based on the spring–mass system and uses the Levenberg–Marquardt algorithm to find the arrangement of vertebral bodies. It represents the spine as rigid geometric transformations from one vertebra to the other when the extremity vertebrae are stationary. The validation process used the Bland–Altman method to compare the Cobb and the intervertebral angles computed by the model with the radiographic exams of eight patients diagnosed with Ankylosing Spondylitis. The results suggest that the model is valid; however, previous clinical information would improve outcomes by customising the lower and upper vertebrae positions, since the study revealed that the C6 rotation slightly influences the computed angles. Applying VM with the new model could make a difference in preventing, monitoring, and early diagnosing spinal disorders. [ABSTRACT FROM AUTHOR]

As an important barrier for high‐level radioactive waste transportation and deep burial disposal, the welding quality of nuclear waste container is particularly important. At present, nuclear waste container is usually manufactured by plasma arc welding. Therefore, in order to manufacture nuclear waste container parts with high quality, based on the finite element simulation software simufact welding, this paper uses a combination of numerical simulation and experimental verification to simulate the temperature field, stress field and deformation of the longitudinal weld of 316L nuclear waste container cylinder body by selecting different welding groove angles. The test results show that the groove angle of the V‐groove increases, the residual stress distribution and size increase, and the deformation increases. The stress value of the I‐shaped groove is between the V‐shaped groove angle of 30° and 45°, but the deformation is the smallest. In practical engineering applications, residual stress and deformation need to be considered comprehensive. Reasonable groove angle plays an important role in controlling residual stress and deformation after welding. [ABSTRACT FROM AUTHOR]

Background and Aims Variation in architectural traits related to the spatial and angular distribution of leaf area can have considerable impacts on canopy-scale fluxes contributing to water-use efficiency (WUE). These architectural traits are frequent targets for crop improvement and for improving the understanding and predictions of net ecosystem carbon and water fluxes. Methods A three-dimensional, leaf-resolving model along with a range of virtually generated hypothetical canopies were used to quantify interactions between canopy structure and WUE by examining its response to variation of leaf inclination independent of leaf azimuth, canopy heterogeneity, vegetation density and physiological parameters. Key Results Overall, increasing leaf area index (LAI), increasing the daily-averaged fraction of leaf area projected in the sun direction (G avg) via the leaf inclination or azimuth distribution and increasing homogeneity had a similar effect on canopy-scale daily fluxes contributing to WUE. Increasing any of these parameters tended to increase daily light interception, increase daily net photosynthesis at low LAI and decrease it at high LAI, increase daily transpiration and decrease WUE. Isolated spherical crowns could decrease photosynthesis by ~60 % but increase daily WUE ≤130 % relative to a homogeneous canopy with equivalent leaf area density. There was no observed optimum in daily canopy WUE as LAI, leaf angle distribution or heterogeneity was varied. However, when the canopy was dense, a more vertical leaf angle distribution could increase both photosynthesis and WUE simultaneously. Conclusions Variation in leaf angle and density distributions can have a substantial impact on canopy-level carbon and water fluxes, with potential trade-offs between the two. These traits might therefore be viable target traits for increasing or maintaining crop productivity while using less water, and for improvement of simplified models. Increasing canopy density or decreasing canopy heterogeneity increases the impact of leaf angle on WUE and its dependent processes. [ABSTRACT FROM AUTHOR]

Originally developed for the moderate resolution imaging spectroradiometer (MODIS) in polar, sun-synchronous low earth orbit (LEO), the Dark Target (DT) aerosol retrieval algorithm relies on the assumption of a surface reflectance parameterization (SRP) over land surfaces. Specifically for vegetated and dark-soiled surfaces, values of surface reflectance in blue and red visible-wavelength bands are assumed to be nearly linearly related to each other and to the value in a shortwave infrared (SWIR) wavelength band. This SRP also includes dependencies on scattering angle and a normalized difference vegetation index computed from two SWIR bands (NDVI SWIR). As the DT retrieval algorithm is being ported to new sensors to continue and expand the aerosol data record, we assess whether the MODIS-assumed SRP can be used for these sensors. Here, we specifically assess SRP for the Advanced Baseline Imager (ABI) aboard the Geostationary Operational Environmental Satellite (GOES)-16/East (ABIE). First, we find that using MODIS-based SRP leads to higher biases and artificial diurnal signatures in aerosol optical depth (AOD) retrievals from ABIE. The primary reason appears to be that the geostationary orbit (GEO) encounters an entirely different set of observation geometry than does LEO, primarily with regard to solar angles coupled with fixed-view angles. Therefore, we have developed a new SRP for GEO that draws the angular shape of the surface bidirectional reflectance. We also introduce modifications to the parameterization of both red–SWIR and blue–red spectral relationships to include additional information. The revised red–SWIR SRP includes the solar zenith angle, NDVI SWIR , and land-type percentage from an ancillary database. The blue–red SRP adds dependencies on the scattering angle and NDVI SWIR. The new SRPs improve the AOD retrieval of ABIE in terms of overall less bias and mitigation of the overestimation around local noon. The average bias of the DT AOD compared to the Aerosol Robotic Network (AERONET) AOD shows a reduction from 0.08 to 0.03, while the bias of local solar noon decreases from 0.12 to 0.03. The agreement between the DT and AERONET AOD is established through a regression slope of 1.06 and a y intercept of 0.01 with a correlation coefficient of 0.74. By using the new SRP, the percentage of data falling within the expected error range (±0.05 % + 15 %) is notably increased from 54 % to 78 %. [ABSTRACT FROM AUTHOR]