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The reliable anchorage and long‐term durability of high‐performance fiber reinforced polymer composites were the decisive factors for engineering applications owing to the anisotropy of materials and the complexity of service environment. In this paper, an innovative glass fiber reinforced polypropylene (GFRPP) self‐anchor plate cable was developed to utilize the high toughness/durability of thermoplastic resin and self‐anchor load‐bearing system. The effects of different reinforcement methods and cable arc angles (10°, 20°, and 30°) on mechanical properties of plate cable were investigated. Water absorption behavior and mechanical properties immersed in alkali solution were tested to evaluate its long‐term service behavior. The thermogravimetric and surface morphology analysis were conducted to reveal the performance evolution mechanism. The results showed through the combination of secondary melting, carbon fiber winding confinement and epoxy reinforcements, the splitting failure of transition zone and interlaminar cracking failure of straight zone for plate cable were effectively avoided. The tensile strength retention of plate cable for arc angles of 10°, 20° and 30° were 45.6%, 41.3%, and 34.0% of GFRPP plate, respectively. Larger arc angle increased the curvature of arc‐straight transition zone and stress concentration near the straight section, leading to interlaminar splitting failure of plate cable at weak transition zone. The tensile strength of plate cable with the immersion time deteriorated obviously until the lowest retention of 29.7%. The degradation mechanism was mainly due to the etching of glass fibers in alkali solution and the formation of pores and internal defects, including fiber/resin interface debonding and resin swelling. The research results were of significance for solving the anchoring problems and promoting the long‐term service reliability in bridge applications. Highlights: The mold can realize reliable molding of glass fiber reinforced polypropylene cables after the reinforcements.The tensile strength retention of plate cable was up to 34.0%–45.6% of plate.Larger arc angle increased the stress concentration near the straight section.Non‐polar polypropylene plate was proved to have better hydrophobic performance.The degradation mechanism of plate cable in alkali solution was revealed. [ABSTRACT FROM AUTHOR]

To understand the historical context of and relationships between, the characteristics of shots at goal and match outcome in the Australian Football League. Observational. Descriptive statistics of shots at goal were calculated and compared across 20 seasons. The location, type, and outcome of all shots at goal (n = 43,254), by all teams (2017–19 & 21), were compared with match outcome. The total number of shots per match and the accuracy of shots haven't changed in two decades. Most teams win by having more shots at goal (Wilcoxon-r effect size 0.63) than their opponent (i.e. "majority strategy") and of these, the number of open shots (0.48) is slightly more important than set shots (0.43), followed by shot accuracy (0.29). However, some teams (14 %) win by taking fewer shots at goal from field locations with a higher likelihood of scoring a goal (i.e. "minority strategy"). Arc angle and shot type can be used to predict the outcome of a shot at goal with 60.3 % classification accuracy. The novel shot-outcome prediction model reported here provides a better opportunity to evaluate goal kicking performance of teams and players, because it accounts for the type and difficulty of the shot. Teams can evaluate the shot accuracy of their players more fairly, by accounting for shot location using the method reported here. Coaches can compare the two shot strategies identified and implement the one that suits the skill profile of their players and increase their likelihood of winning. [ABSTRACT FROM AUTHOR]

The high performance and long life of engineering structures can be realized through replacing traditional steel materials with glass fiber reinforced polypropylene composites with high toughness/durability, flexibility design and recycling. In addition, the anchorage problem of composites needs to be solved by developing new anchorage technologies or forms. In the present paper, a new type cable-anchor component was developed to prolong the service life and realize the reliable anchoring of composite. The influence mechanism of arc angle (10°, 20°, and 30°) on the mechanical properties of cable-anchor component was evaluated through the experimental and mechanical simulation. The durability evolution of cable-anchor component exposed to alkali solution environment was investigated through macro-performance test and microstructure analysis. The results showed the tensile strength retention of cable-anchor component was up to 88.7 % at the arc angles of 10° under the circumferential constraint of carbon fiber. Larger arc angle increased the stress concentration and fiber misalignment of transition area between arc and straight segments, leading to the formation and propagation of defects or cracks in transition areas and early fracture failure. The saturated water absorption and diffusion coefficient of glass fiber reinforced polypropylene composites were obtained to be 0.78 % and 4.41×10−14 m2/s, respectively. Compared with nylon 6 and epoxy resin, polypropylene has excellent hydrophobic properties with the diffusion coefficient ratio of 0.0077 and 0.024. At the longest immersion, the tensile strength retentions of cable-anchor component were 61.8 % and the failure mode changed from component longitudinal splitting to brittleness fracture of arc region. The degradation mechanism was attributed to the initial defects of arc section formed and expanded under the complex stress and corrosive medium, which further aggravated the fiber/resin interfacial debonding. Through comparing with other glass fiber reinforced thermoplastic and thermosetting composites, the cable-anchor component has higher tensile strength retention after the immersion of alkaline solution owing to excellent hydrophobicity behavior of polypropylene and efficient preparation process.

A mechanism to reduce the porosity by changing the arc angle during aluminum alloy welding was studied. Industrial computed tomography was used to scan the welds with different arc angles, and the scanned model was processed by a specific software package to obtain the digital size and position of weld pores. The forces acting on the pores in the molten pool explained the test results that the number of pores decreases and the average size increases. As the inclination angle of the arc increased, the vertical component that prevented the bubble from rising decreased, and the horizontal component that pushed the molten metal flow and promoted the nucleation and growth of the bubbles increased. A horizontal movement during the droplet transition as the arc inclination was produced, which was conducive to the growth and overflow of bubbles. The theoretical analysis and temperature field measured by a far-infrared with different torch angle showed that when the arc was tilted from 0, the shape of the molten pool changed from the circle to the ellipse. The long axis of the ellipse increased as the bevel angle of the arc increased. This showed that the molten metal existed a longer time for the bubbles to escape from the molten pool when the angle of the arc increased. The paper provides fundamental insights into a mechanism for porosity reduction during the welding of Al alloys.

This study investigated position dependence in planning target volume ( PTV)-based and robust optimization plans using full-arc and partial-arc volumetric modulated arc therapy ( VMAT). The gantry angles at the periphery, intermediate, and center CTV positions were 181°-180° (full-arc VMAT) and 181°-360° (partial-arc VMAT). A PTV-based optimization plan was defined by 5 mm margin expansion of the CTV to a PTV volume, on which the dose constraints were applied. The robust optimization plan consisted of a directly optimized dose to the CTV under a maximum-uncertainties setup of 5 mm. The prescription dose was normalized to the CTV D99% (the minimum relative dose that covers 99% of the volume of the CTV) as an original plan. The isocenter was rigidly shifted at 1 mm intervals in the anterior-posterior (A-P), superior-inferior (S-I), and right-left (R-L) directions from the original position to the maximum-uncertainties setup of 5 mm in the original plan, yielding recalculated dose distributions. It was found that for the intermediate and center positions, the uncertainties in the D99% doses to the CTV for all directions did not significantly differ when comparing the PTV-based and robust optimization plans ( P > 0.05). For the periphery position, uncertainties in the D99% doses to the CTV in the R-L direction for the robust optimization plan were found to be lower than those in the PTV-based optimization plan ( P < 0.05). Our study demonstrated that a robust optimization plan's efficacy using partial-arc VMAT depends on the periphery CTV position. [ABSTRACT FROM AUTHOR]

In this article, thermal buckling and natural frequency of a curved functionally graded (FG) nanobeam in a thermal environment based on Eringen’s theory is investigated. Dimension of structure is in small scale, its geometric is curved, and properties of material vary in radial direction. In order to develop differential equation and boundary condition, Hamilton’s principle is adopted. Properties of material are a function of two variables of radial thickness and temperature. After developing equation of motion in thermal environment, analytical solution has been employed in order to obtain the amount of frequency and thermal buckling. Free vibration of a curved FG nanobeam subjected to in-plane thermal load may show zero frequency magnitude at a certain temperature, which specifies the existence of bifurcation type of instability. In numerical section, frequency responses have been studied one time based on temperature-dependent material property and another time based on temperature-independent material property and influences for parameters such as nonlocal parameter, power-law, mode number, temperature changes, and arc angle on natural frequency and critical temperature have been investigated. Results have shown that if properties of material are dependent on temperature, then expected frequency will be less than the case in which properties are independent of temperature. Performed validation certifies correctness of obtained results. Results indicate that critical temperature increasing the arc angle leads to a decrease in amount of dimensionless frequency, and this matter represents the importance of specification of critical temperature in curved structures. [ABSTRACT FROM AUTHOR]

A mathematical model of anterior inter-arch relations was described in a previous article.1 This model is modified and manipulated and, using hypothetical dental measurements, results are generated and presented. The present work continues the two-dimensional examination of anterior dental relations in the first article, the emphasis remaining on incisor and cauine overjet.

Three-dimensional numerical computations are performed to investigate the performance of curved winglets mounted on a rectangular channel. The concave and convex shapes of curved rectangular winglet vortex generators (RWVGs) are named according to flow facing surface. Curvature of winglet mainly depends on arc angle, radius of curvature, arc length and chord length. Present study investigates the influence of arc angle variation of curved RWVG on flow and thermal characteristics for fixed chord length. Arc length and radius of curvature of curved RWVG vary according to arc angle. With the help of streaklines plots and iso-Q surfaces, flow behavior around the curved RWVG has been investigated. Heat transfer enhancement of curved RWVGs has been examined by using the dimensionless parameters surface-averaged Nusselt number, while pressure loss is estimated by friction factor. The overall thermohydraulic performance of curved RWVGs is inspected by thermal performance factor. Investigations of secondary flow intensity are carried out to understand its impact on heat transfer mechanism. From the investigation of secondary flow, it is observed that secondary flow provides a supplement to the traditional method of analyzing heat transfer performance. [ABSTRACT FROM AUTHOR]

When a conducting shallow cavity is placed behind an equiangular spiral to obtain a unidirectional beam, the inherent wideband characteristics of the spiral deteriorate. To restore the wideband characteristics, a ring-shaped absorbing strip (R-ABS) is placed under the spiral arms. Analysis of the equiangular spiral with the R-ABS is performed using the finite-difference time-domain method. It is found that the R-ABS successfully restores the wideband characteristics. Subsequently, the R-ABS is divided into two absorbing strips, each specified by an arc-angle . Analysis reveals that the radiation characteristics obtained using the R-ABS are reproduced when the arc-angle is greater than . Throughout this paper an extremely small cavity depth is selected for the analysis: 0.07 wavelength at the lower operating design frequency of 3 GHz. [ABSTRACT FROM PUBLISHER]

The joint structure of a transducer horn-holder assembly for a wire bonder was examined through finite element contact analysis. Three-dimensional modeling and analysis was carried out to survey the internal physics of this structure and to verify the accuracy of a proposed computation relative to measurement. After validation, a two-dimensional model was built to conduct parametric studies and improve the efficiency and speed of the computation. Several factors such as boundary conditions, modeling boundary, and mesh density, were considered to obtain consistency with the three-dimensional analysis. Arc angle and the position of each holder boss were chosen as design parameters. A designed computation approach was applied for efficiency in computation. As a result, a guideline for holder boss design was suggested, and the main factors and their influence on stress concentration in the transducer horn were surveyed. [ABSTRACT FROM PUBLISHER]

A mechanism to reduce the porosity by changing the arc angle during aluminum alloy welding was studied. Industrial computed tomography was used to scan the welds with different arc angles, and the scanned model was processed by a specific software package to obtain the digital size and position of weld pores. The forces acting on the pores in the molten pool explained the test results that the number of pores decreases and the average size increases. As the inclination angle of the arc increased, the vertical component that prevented the bubble from rising decreased, and the horizontal component that pushed the molten metal flow and promoted the nucleation and growth of the bubbles increased. A horizontal movement during the droplet transition as the arc inclination was produced, which was conducive to the growth and overflow of bubbles. The theoretical analysis and temperature field measured by a far-infrared with different torch angle showed that when the arc was tilted from 0, the shape of the molten pool changed from the circle to the ellipse. The long axis of the ellipse increased as the bevel angle of the arc increased. This showed that the molten metal existed a longer time for the bubbles to escape from the molten pool when the angle of the arc increased. The paper provides fundamental insights into a mechanism for porosity reduction during the welding of Al alloys. [ABSTRACT FROM AUTHOR]

Severely calcified plaque is of great concern when planning and implementing a stenting intervention. In this work, computational models were developed to investigate the influence of calcium characteristics on stenting outcomes. The commonly used clinical measurements of calcium (i.e., the arc angle, maximum thickness, length, and volume) were varied to estimate stenting outcomes in terms of lumen gain, stent underexpansion, strut malapposition, and stress or strain distributions of the stenotic lesion. Results have shown that stenting outcomes were most sensitive to the arc angle of the calcium. A thick calcium with a large arc angle resulted in poor stenting outcomes, such as severe stent underexpansion, D-shaped lumen, increased strut malapposition, and large stresses or strains in the plaque. This was attributed to the circumferential stretch of the tissue. Specifically, the noncalcium component was stretched significantly more than the calcium. The circumferential stretch ratios of calcium and noncalcium component were approximately 1.44 and 2.35, respectively, regardless of calcium characteristics. In addition, the peak stress or strain within the artery and noncalcium component of the plaque occurred at the area adjacent to calcium edges (i.e., the interface between the calcium and the noncalcium component) coincident with the location of peak malapposition. It is worth noting that calcium played a protective role for the artery underneath, which was at the expense of the overstretch and stress concentrations in the other portion of the artery. These detailed mechanistic quantifications could be used to provide a fundamental understanding of the impact of calcium quantifications on stent expansions, as well as to exploit their potential for a better preclinical strategy., (Copyright © 2019 by ASME.)