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In the article, the content of the skills intended to become the subject of students in teaching materials for the "Point in space, straight line, plane" educational unit, which is included in the content of the Mathematics subject in the X classes of general education schools, is presented. Attention is directed to the place of the content elements that perform the "enabling function" in the formation of the mentioned skills in the "Point in space, straight line, plane" educational unit and to the technology of turning them into action in the students' cognition. "Point, straight line and plane in space" of the transformed elements in the educational unit "Point, straight line and plane" The mutual position of straight lines and planes in space", "Parallelism of a straight line and a plane. Perpendicularity of a straight line to a plane. The angle between a straight line and a plane", "Theorem of three perpendiculars", "Angle between two planes”. “Dihedral angles. Perpendicular planes", "Parallel planes. Projections and ProblemSolving" are appropriate to make it into a system on topics. We should note that the task system, which serves to organize and manage the educational process for mastering the content elements presented by the students, should contain verbs that are required to be performed on the topics. It included examples of tasks in the work's content.

Summary Laryngeal images obtained via high-speed videoendoscopy are an invaluable source of information for the advancement of voice science because they can capture the true cycle-to-cycle vibratory characteristics of the vocal folds in addition to the transient behaviors of the phonatory mechanism, such as onset, offset, and breaks. This information is obtained through relating the spatial and temporal features from acquired images using objective measurements or subjective assessments. While these images are calibrated temporally, a great challenge is the lack of spatial calibration. Recently, a laser-projection system allowing for spatial calibration was developed. However, various sources of optical distortions deviate the images from reflecting the reality. The main purpose of this study was to evaluate the effect of the fiberoptic flexible endoscope distortions on the calibration of images acquired by the laser-projection system. Specifically, it is shown that two sources of nonlinear distortions could deviate captured images from reality. The first distortion stems from the wide-angle lens used in flexible endoscopes. It is shown that endoscopic images have a significantly higher spatial resolution in the center of the field of view than in its periphery. The difference between the two could lead to as high as 26.4% error in calibrated horizontal measurements. The second distortion stems from variation in the imaging angle. It is shown that the disparity between spatial resolution in the center and periphery of endoscopic images increases as the imaging angle deviates from the perpendicular position. Furthermore, it is shown that when the imaging angle varies, the symmetry of the distortion is also affected significantly. The combined distortions could lead to calibrated horizontal measurement errors as high as 65.7%. The implications of the findings on objective measurements and subjective visual assessments are discussed. These findings can contribute to the refinement of the methods for clinical assessment of voice disorders. Considering that the studied phenomena are due to optical principles, the findings of this study, especially those related to the effects of the imaging angle, can provide further insights regarding other endoscopic instruments (eg, distal-chip and rigid endoscopes) and procedures (eg, gastroendoscopy and colonoscopy).

s This paper investigates the effect of porosity on active damping of geometrically nonlinear vibrations (GNLV) of the magneto-electro-elastic (MEE) functionally graded (FG) plates incorporated with active treatment constricted layer damping (ATCLD) patches. The perpendicularly/slanted reinforced 1–3 piezoelectric composite (1–3 PZC) constricting layer. The constricted viscoelastic layer of the ATCLD is modeled in the time-domain using Golla-Hughes-McTavish (GHM) technique. Different types of porosity distribution in the porous magneto-electro-elastic functionally graded PMEE-FG plate graded in the thickness direction. Considering the coupling effects among elasticity, electrical, and magnetic fields, a three-dimensional finite element (FE) model for the smart PMEE-FG plate is obtained by incorporating the theory of layer-wise shear deformation. The geometric nonlinearity adopts the von Karman principle. The study presents the effects of a variant of a power-law index, porosity index, the material gradation, three types of porosity distribution, boundary conditions, and the piezoelectric fiber's orientation angle on the control of GNLV of the PMEE-FG plates. The results reveal that the FG substrate layers' porosity significantly impacts the nonlinear behavior and damping performance of the PMEE-FG plates.

Background The femoral anterior tangent (FAT) line refers to a line parallel to the anterior surface of the distal femur in the axial plane. This study aimed to evaluate the effectiveness of a new operation support system which uses the FAT line to set the femoral component rotational alignment in total knee arthroplasty (TKA). Methods A total of 170 consecutive knees in 139 patients undergoing primary TKA with the JIGEN (Jig Engaged Three-dimensional (3D) Pre-Operative Planning Software for TKA) operation support system was examined. The JIGEN system creates 3D models of bones using computed tomography data, allowing for surgical simulations such as positioning of implants while calculating positions of the intramedullary alignment rod (IM rod) and surgical jig. We retrospectively analyzed the FAT line angle relative to the surgical epicondylar axis (SEA) on the axis plane perpendicular to the IM rod and evaluated the accuracy of the femoral component alignment after TKA with the 3D measurement system. Results The FAT line was 9.6° ± 3.7° (range, 1.4°–20.4°) internally rotated relative to the SEA. The average absolute error was 1.4° ± 1.1° in the coronal plane, 2.0° ± 1.5° in the sagittal plane, and 1.6° ± 1.3° in the axial plane. The femoral component outliers (i.e., >3° away from the goal alignment) were 7.7% in the coronal plane, 20.6% in the sagittal plane, and 10.3% in the axial plane. Conclusions Our findings suggest that the FAT line is a reliable and reproducibly identifiable axis for the accurate determination of proper rotational alignment in TKA. An operation support system which uses the FAT line for determining intraoperative femoral component rotation can effectively achieve highly accurate positioning of the femoral component in TKA.

Half-metallic Heusler alloys typically have in-plane magnetic anisotropy, which can be converted to perpendicular by attaching MgO or heavy metal, e.g., Pt, layers as similarly applied for conventional ferromagnets. Recently we have found body-centered cubic (bcc) seed layers, e.g., V and W, to induce perpendicular anisotropy in Heusler-alloy films above, however, they show small giant magnetoresistive (GMR) ratios in spin-valve structures to date. This is partially because of the large resistivity of the seed layer and the nonmagnetic layer in the spin-valve. In this study, we have systematically investigated nonmagnetic overlayers and have found that a Ag layer best maintains the perpendicular anisotropy. The corresponding GMR devices have then been fabricated and characterized, achieving the GMR ratio of ~0.03% at room temperature. Such bcc seed layers can offer an alternative method for perpendicularly magnetized GMR junctions for applications.

In this paper, fixed-time cooperative guidance laws are designed for multiple missiles to simultaneously attack a maneuvering target at desired terminal angles. The three-dimensional (3D) guidance commands consist of tangential acceleration along line-of-sight (LOS) direction to achieve a salvo attack and normal acceleration perpendicular to the LOS direction to realize a terminal angle constrained interception. First, the tangential acceleration is derived from a distributed cooperative protocol to guarantee the fixed-time consensus of impact times for multiple missiles. Second, based on the integral sliding manifold and fixed-time reaching law, the normal acceleration is developed for each missile to converge the LOS angle to the desired value within a fixed time. In particular, the unknown target acceleration components are estimated by fixed-time observers and compensated in the guidance commands. The fixed-time stability of the proposed cooperative guidance law is rigorously proved and the explicit estimate for the convergence time is theoretically provided. Then, the proposed methods are utilized to realize the cooperative mission in the planar guidance scenario. Finally, the effectiveness and advantages of the proposed cooperative guidance laws are demonstrated through numerical simulations with comparative studies.

Fast analysis and wideband design using method of moments are proposed for a radiating subarray in a parallel-plate slot array antenna with perpendicular-corporate feed in this paper. Applying the method of moments and a genetic algorithm to the subarray design enables fast electromagnetic analysis and easy optimization for wideband performance. A comparison with the HFSS simulation proves the superior efficiency of designing by the proposed approach. The simulated bandwidth of reflection below -14 dB for the subarray gets up to 13.1% by a two-layer geometry in this paper, much improved from the 7.7% by a three-layer structure or the 11.4% by a four-layer structure using the conventional design method based on the HFSS simulation. The fabricated 16×16-slot array shows a measured bandwidth of 13.2% (58.7 – 67.0 GHz) with a reflection below -10 dB and a high antenna efficiency greater than 70% over a bandwidth of 11.2% (59.7 GHz – 66.8 GHz). At the design frequency of 61.5 GHz, a high measured gain of 32.9 dBi with antenna efficiency of 81.8% is demonstrated.

Anisotropic porous boron carbide (B4C) structures were successfully produced, for the first time, using the magnetic field-assisted freeze casting method. The effect of the magnetic field on the structure and mechanical strength of the formed porous B4C was compared for two different magnetic field directions that were either aligned with ice growth (vertical), or perpendicular to the ice growth direction (horizontal). It was shown that applying even a weak horizontal magnetic field of 0.1–0.3 T noticeably affected the alignment of mineral bridges between lamellar walls. Both the porosity and the channel widths decreased with increasing horizontal magnetic field strength. In the case of a vertical magnetic field, a larger strength of 0.4 T was required for highly aligned lamellar walls and larger channel widths. Compression strength tests indicated that the application of magnetic fields led to more homogeneously aligned channels, which resulted in increased compression strength in the longitudinal (parallel to the ice growth) direction. Applying a vertical magnetic field of 0.4 T with a cooling rate of 2 °C/min during the freezing step of the magnetic field-assisted freeze-casting method was found to result in the best conditions for producing highly anisotropic structures with large channel widths and fewer mineral bridges, which led to an increase in the mechanical strength.

This paper presents a novel linear generator structure of three-phase tubular staggered transverse flux permanent magnet linear generator (TSTF-PMLG) for wave energy conversion. Compared with conventional TF-PMLGs, the new structure has a simpler magnetic flux path, high mechanical strength, low cogging force and more suitable for lowspeed direct driven situation. In the primary of TSTF-PMLG, a nonuniform teeth steel sheets structure is used and steel sheets of different phases are in different angel so that the groove can be separated by staggered steel sheets in the plane perpendicular to the direction of movement. By the analytical model, the operation principle of the motor is explained. Then through the finite element analysis, the distribution of the main flux and leakage flux, the no-load characteristics and output power of TSTF-PMLG are analyzed in detail. And the influence of the lamination factor on the output characteristics of the TSTF-PMLG is obtained. Subsequently the appropriate design parameters of the TSTF-PMLG are selected. During the TSTF-PMLG processing, the method of mixing silicon steel sheets and fiberglass board is used to limiting the lamination factor. Finially, a prototype of 150W rated power and 79% rated efficiency is presented. And the experimental results verify the theoretical analysis.

We use a computational phase-field model together with analytical analysis to study how intercellular active forces can mediate individual cell morphology and collective motion in a confluent cell monolayer. We explore the regime where intercellular forces dominate the tissue dynamics, and polar forces are negligible. Contractile intercellular interactions lead to cell elongation, nematic ordering, and active turbulence characterized by motile topological defects. Extensile interactions result in frustration, and perpendicular cell orientations become more prevalent. Furthermore, we show that contractile behavior can change to extensile behavior if anisotropic fluctuations in cell shape are considered.

The chapter focuses on fundamental theories, formulas, solution methods, and a set (toolbox) of MATLAB functions for the static analysis of linearly elastic bodies in two and three dimensions. The formulation and solution of an elasticity problem requires basic equations—equations of equilibrium, strain-displacement relations (geometric relations), conditions of compatibility, stress-strain relations (constitutive law), and boundary conditions. According to the strain-displacement relations, the six components of strain at a point are completely determined by the three displacement components u , v , and w . Therefore, the strain components cannot be arbitrary functions of x , y , and z . Depending on the geometric configuration of the elastic body in consideration, a two-dimensional elasticity problem usually falls into one of the two categories—plane stress and plane strain. A problem of plane strain is concerned with a long prismatic or cylindrical body. The body is subjected to external loads that are perpendicular to the longitudinal ( z ) axis and do not change along the length. It is assumed that frictionless constraints are imposed at the two ends of the body, which permit x , y deformation, but do not allow the displacement in the z direction.

PURPOSE To evaluate the influence of anterior capsule rhexis shape, dimension and eccentricity on IntraOcular Lens (IOL) position. SETTING laboratory investigation. DESIGN Computational modelMethods: a finite element model of the human crystalline lens capsule and zonule was created and the anterior capsule opened to simulate centred and decentred circular and elliptic rhexis. The model calculated capsular bag stress, IOL rotation, tilt, decentration and vaulting, related to both capsular landmarks (absolute) and to a reference IOL position defined as that obtained with a 5 mm circular and centred rhexis. RESULTS Average Von Mises stress along IOL major axis Z was significantly higher than along the perpendicular X-axis in all cases (p

The anisotropic mechanical properties of ultrasound freeze cast epoxy-ceramic composite materials were studied by measuring flexural strength and fracture resistance curves (R-curves) using both unnotched and notched three-point beam bending experiments, respectively, cut in three different orientations relative to the directional freezing axis. Three ultrasound frequencies of 0.699, 1.39 and 2.097 MHz were used in order to introduce different length scales into the microstructure, with 0 MHz used as the control samples. For all cases, the composites showed higher strength and fracture resistance when the crack plane cut across the direction of ice growth (denoted as the YX orientation). The anisotropic properties were more evident for the material produced without ultrasound (0 MHz) where the flexural strength was approximately 160% higher for the YX orientation compared to two orthogonal orientations. Most of the fracture resistance increase was found to occur within a crack extension, Δa, of ∼0.5 mm. Comparing the fracture resistance at Δa = 0.5 mm for the highly anisotropic 0 MHz samples showed that the YX orientation was approximately 86% tougher than the two orthogonal orientations. When the ultrasound operation frequencies of 0.699, 1.39 and 2.097 MHz were applied, the amount of anisotropy in the strength and fracture resistance gradually decreased as the operating frequency increased. The high strength and fracture resistance for the YX orientation was attributed to the alignment of the ceramic particles along the freeze front direction creating a barrier for crack propagation. Ultrasound modifies the material microstructure, introducing relatively dense ceramic layers perpendicular to the freezing front direction that act as an additional, orthogonal barrier to crack propagation. The addition of the denser layers acts to improve the mechanical properties in the weaker orientations and reduce the overall anisotropy.

The entropy-driven monolayer assembly of hexagonal prisms and cylinders was studied under hard slit confinement. At the conditions investigated, the particles have two distinct and dynamically disconnected rotational states: unflipped and flipped, depending on whether their circular/hexagonal face is parallel or perpendicular to the wall plane. Importantly, these two rotational states cast distinct projection areas over the wall plane that favor either hexagonal or tetragonal packing. Monte Carlo simulations revealed a re-entrant melting transition where an intervening disordered Flipped-Unflipped (FUN) phase is sandwiched between a fourfold tetratic phase at high concentrations and a sixfold triangular solid at intermediate concentrations. The FUN phase contains a mixture of flipped and unflipped particles and is translationally and orientationally disordered. Complementary experiments were conducted with photolithographically fabricated cylindrical microparticles confined in a wedge cell. Both simulations and experiments show the formation of phases with comparable fraction of flipped particles and structure, i.e., the FUN phase, triangular solid, and tetratic phase, indicating that both approaches sample analogous basins of particle-orientation phase-space. The phase behavior of hexagonal prisms in a soft-repulsive wall model was also investigated to exemplify how tunable particle–wall interactions can provide an experimentally viable strategy to dynamically bridge the flipped and unflipped states.

The grain orientation control via twinning activity on deformation features is of great significance to offer a key insight into understanding the deformation mechanism of Mg alloy sheets. The {10–12} twinning were performed by pre-strain paths, i.e., tension (6%) and compression (5%) perpendicular to the c-axis along extrusion direction (ED), to investigate the microstructural evolution and mechanical properties of AZ31 Mg alloy sheets. The distinction in the texture evolution and strain hardening behavior was illustrated in connection with the pre-strain paths for the activities of twinning and slip. The result shows that the activation of the deformation mode was closely bound up with the grain orientation and the additional applied load direction. The {10–12} twin-texture components with c-axis//ED were generated by pre-compression, which can provide an appropriate alternative to accommodate the thin sheet thickness strain and enhance the room temperature formability of Mg alloy sheet.

We investigated the effect of magnetic coupling (the energy constant of unit area: Jcpl) between CoFeB free layers on thermal stability factor Δ in Magnetic Tunnel junction (MTJ) with CoFeB/MgO double Interfacial Perpendicular Magnetic Anisotropy (IPMA). We newly introduced Jcpl in models for calculations, which were based on magnetic domain propagation model when MTJ diameter d is larger than critical diameter dc and magnetization coherent rotation model when d ≤ dc. With increasing Jcpl, Δ increases and saturates when Jcpl is over a critical value Jcpl_c. Magneto-static coupling constants (Jstat) between the free layers were also calculated. Jstat is so smaller than Jcpl_c and cannot maximize Δ by itself, that an interlayer exchange coupling (the critical energy constant of unit area: Jex_c) is required to cover the difference between Jcpl_c and Jstat. Jex_c also rapidly increases with the decrease of d and reaches a plateau of 0.15 mJ/m2 in d ≤ 30 nm. MTJ devices with a smallest Jex (=0.01 mJ/m2) and a moderate PMA (constant per unit area: Keff t*) were made and Δs were evaluated by experiments. The experimental Δs were fitted by the calculations with adjusting stiffness constants As. The calculated Δs and the experimental Δs were in good agreement when the As was a smaller value than that of the blanket film. Since the experimentally used Jex value was almost zero, Δ values were estimated when Jex was a greater value of 0.15mJ/m2. As a result, 30% enhancement of Δ was obtained at the smallest d = 20 nm.

We developed perpendicular magnetic tunneling junctions (MTJs) with four synthetic antiferromagnetically coupled Co/Pt layers (Quad-SyF) and investigated their magnetic and transport properties. The quad SyF comprised four Co/Pt layers and three 0.9 nm-thick Ru coupling layers, which consisted of Co/Co/Pta/Ru/Co/Co/Ptb/Ru/Co/Co/Ptc/Ru/Co/Co/Ptd from top to bottom. The exchange coupling field (Hex) reached a maximum of 1 T when the values of a, b, c, and d were 1, 2, 2, and 1, respectively. The tunnel magnetoresistance ratio of the MTJ with the Quad-SyF and the second-peak conventional Double-SyF increased as the annealing temperature was increased up to 400°C, whereas that of the MTJ with the first-peak conventional Double-SyF degraded at temperatures of more than 350°C in the blanket films. A 55 nm-diameter MTJ with Quad-SyF was found to be stable even against an external magnetic fields up to 300 mT. In contrast, in the conventional Double-SyF, the reference-layer magnetization direction flips at around 250 mT. The shift magnetic field of the MTJ with Quad-SyF becomes approximately zero when the values of a, b, c, and d were 1, 4, 1, and 2, respectively. No back-hopping of the MTJ with Quad-SyF was observed even for the write pulse width (tW) down to 10 ns. In contrast, an MTJ with conventional Double-SyF exhibited back-hopping. In the patterned MTJ with conventional Double-SyF, as the MTJ size decreases, the coercive field of Co/Pt significantly increases and Hex decreases, causing the m-H curve of the reference layer to cross the zero magnetic field. This enables both parallel and antiparallel configurations for the top and bottom Co/Pt layers in Double-SyF at the zero magnetic field, which could induce back-hopping. However, the m-H curves of the reference layer in the patterned MTJ with Quad-SyF are far from the zero magnetic field owing to the high Hex and low Hc, which could lead to the suppression of back-hopping.

This work mainly focuses on the off-axis compressive behavior of cross-laminated bamboo and timber (CLBT) wall elements. In total, 224 off-axis specimens were tested, which were made from hem-fir lumber and bamboo mat-curtain panels or just hem-fir lumber. Based on the in-plane compressive failure criteria and prediction models for the off-axis apparent compressive modulus, the mechanical property parameters of the off-axis tests were predicted. Experimental results showed that the main failure modes were slender failure zones along the parallel or perpendicular to the off-axis angles and delamination failures between the layers. The orthogonal structures inside the off-axis specimens dispersed the compressive performance of the major strength direction. Compared with glued-laminated timber specimens, the off-axis compressive performance of cross-laminated timber and CLBT specimens varied more smoothly with the increase of the off-axis angle. In addition, the characteristics of the model forms and materials affected the accuracy of the off-axis compressive property prediction models. The results in this paper can provide some inspiration for a series of innovative full-size CLBT wall members.

In lyotropic chromonic liquid crystals (LCLCs), twist distortion of the nematic director costs much less energy than splay or bend distortion. This feature leads to novel mirror-symmetry breaking director configurations when the LCLCs are confined by interfaces or contain suspended particles. Spherical colloids in an aligned LCLC nematic phase, for example, induce chiral director perturbations (“twisted tails”). The asymmetry of rod-like particles in an aligned LCLC offer a richer set of possibilities due to their aspect ratio (α) and mean orientation angle (〈θ〉) between their long axis and the uniform far-field director. Here we report on the director configuration, equilibrium orientation, and angular diffusion of rod-like particles with planar anchoring suspended in an aligned LCLC. Video microscopy reveals, counterintuitively, that two-thirds of the rods have an angled equilibrium orientation (〈θ〉 ≠ 0) that decreases with increasing α, while only one-third of the rods are aligned (〈θ〉 = 0). Polarized optical video-microscopy and Landau–de Gennes numerical modeling demonstrate that the angled and aligned rods are accompanied by distinct chiral director configurations. Angled rods have a longitudinal mirror plane (LMP) parallel to their long axis and approximately parallel to the substrate walls. Aligned rods have a transverse and longitudinal mirror plane (TLMP), where the transverse mirror plane is perpendicular to the rod's long axis. Effectively, the small twist elastic constant of LCLCs promotes chiral director configurations that modify the natural tendency of rods to orient along the far-field director. Additional diffusion experiments confirm that rods are angularly confined with strength that depends on α.

Synthetic aperture radar (SAR) can monitor the sea surface imprints of tropical cyclones (TCs) with high spatial resolution, day and night. Automatically locating TC center positions in SAR images is a challenging task. This article developed a two-stage, fully automatic TC-center estimation algorithm. First, the sea surface wind directions (SSWDs) at SSWD points are retrieved by the improved local gradient (ILG) method. We incrementally deflected the SSWD outward at a 0.5° angle from -50° to 10° (the negative angles represent clockwise deflection). The heat maps are generated for each of the 121 angles, and the values at each heat map are the cumulative numbers of the lines perpendicular to the compensated SSWDs. The site corresponding to the maximum cumulative number in all 121 heat maps is the coarsely estimated center position. This center search is the culmination if it falls outside the SAR image. Otherwise, the second stage is triggered, and the sub-SAR image (150 km x 150 km) centered at the coarsely estimated center position is extracted. Then, the first-stage procedure is repeated with the sub-SAR image to precisely estimate the center position. Optionally, the precisely estimated center position can be further adjusted by considering that normalized radar cross section (NRCS) is normally minimal at the TC center. We applied the algorithm to 87 SAR images. Five of these images do not contain TC centers. The results are in good agreement with the visually located TC center positions and those in the best track (BT) datasets.

Surface microtexturing accomplishes a substantial role in enhancing the interfacial functional performance of machine-driven components. For producing good-quality square micropatterns, maskless electrochemical micromachining (EMM) is a viable option. Maskless EMM is employed for producing micropatterns, wherein the workpiece remains close by interaction with the mask tightly enclosed to the coated tool surface, and the electrolysis of job involves in the enclosed cell. The special micropatterning setup is developed to produce the good quality square micropatterns including micropatterning cell, pulsed electrical unit and perpendicular cross flow electrolyte system. The developed flow method on the job surface in this unit produces better good quality micropatterns. A reused textured tool and developed flow method is applied in maskless EMM in an enclosed unit, which eradicates the sludges and fabricate micropatterns with higher depth. This unique method is an efficient approach for improving the dimensional accuracy of micropatterns. The influences of input criteria, viz. voltage, duty ratio and frequency are studied on surface roughness, current efficiency, length overcut, and textured depth using this technique. The experimental outcomes show that the best parametric combination, viz. 30% duty ratio, 5 kHz frequency and 8 V voltage, enhances the micropatterned quality. A study has been approached based on micrographs for attaining the best input criteria combination.

This paper describes an analytical model for the well-known optical knife-edge displacement sensor that predicts the relationship between the knife-edge displacement and photointerrupter output. The model includes: 1) the geometry of a rectangular knife-edge profile penetrating a circular laser beam perpendicular to the beam axis; and 2) the Gaussian intensity profile for the beam cross-section. A comparison between the model predictions and measured photointerrupter for a linear range of knife-edge displacements is provided. It is shown that good agreement is obtained without model calibration.

Reasonable laser process parameters and heating paths are crucial in laser forming (LF) technology. Obtaining the proper laser processing parameters and the heating path is the decisive factor to determine the forming efficiency and precision of the complex 3D surfaces with double curvature. First, the 3D target surfaces with double curvature were developed in this paper to flat plates through the finite element numerical simulation tool, and the magnitude and direction of in-plane and bending strains were obtained; the direction perpendicular to the principal strain is the direction of the heating paths. Second, the database of laser process parameters and principal strains was established to determine the proper laser process parameters. Finally, combined with the above laser parameters and heating paths, the “pillow” and “spherical” surfaces were obtained, and the accuracy of this method was verified by experiments.

In this paper, a phased array antenna with an integrated metasurface is designed to achieve wideband and wide-angle scanning. Generally, the coupling between adjacent elements changes significantly as the scanning angle increases, resulting in limited scanning coverage. Two mutually perpendicular metasurface slabs are designed to achieve wide-angle scanning. The mutual coupling is reduced by properly tuning the dimension of the metasurface. Two perpendicular linear arrays were fabricated to verify the design. The measured 3-dB beamwidth of the active element pattern (AEP, in the array environment) with the integrated metasurface is about 150° in the E-plane and 109° in the H-plane, which is suitable for wide-angle scanning. The simulated and measured results indicate that the beam can scan from -78° to 78° with a 3-dB gain fluctuation in the E-plane array and a wide frequency range from 10 GHz to 12.5 GHz (22.2%). In the H-plane array, the scan angle ranges from -69° to 69° with a 3-dB gain fluctuation and a relative bandwidth of 11%.

The effects of the different surface structure units due to “Z-pins like” V0.9-Si0.1 rods on the improvement of the ablation resistance of C/C–ZrC–SiC were investigated. The ablation properties of the V0.9-Si0.1 rods acting on the surface of short-cut fibre web and laminated layers were tested for different ablation times. The results showed that although the ablation resistances of the composites with different surface structure units improved using neoteric “Z-pins like” V0.9-Si0.1 rods as polybasic multiphase oxide compensators, the improvement mechanisms were different. For an ablation time less than 180 s, the rods perpendicular to the short-cut fibre web resulted in a higher improvement in ablation resistance by a liquid/gas multicomponent oxide compensation mechanism. Whereas, for an ablation time over 180 s, the rods perpendicular to the laminated layers resulted in a higher improvement because of the oxide melting erosion experienced by the short-cut fibre web surface.

A model of charge hopping transport that accounts for anisotropy of localized states and Coulomb interaction between charges is proposed. For the anisotropic localized states the degree of orientation relates exponentially to the ratio of conductivities in parallel and perpendicular directions, while the ratio of Seebeck coefficients stays nearly unaffected. However, the ratio of Seebeck coefficients increases if Coulomb interaction is screened stronger in a direction parallel to the predominant orientation of the localized states. This implies two different physical mechanisms responsible for the anisotropy of thermoelectric properties in the hopping regime: electronic state localization for conductivities, and screening for Seebeck coefficients. This provides explanation for recent experimental findings on tensile drawn and ribbed polymer films., 7 pages, 4 figures

This letter proposes an automated perpendicular parking system using approximated clothoid-based local path planning and a virtual towing method. Clothoid path planning provides smooth maneuvering, but we cannot obtain a closed-form solution. Further, it costs computational overhead. To cope with these problems, we present a novel vehicle control algorithm with approximated clothoid-based local path planning. We show that a parking control system could be presented as a closed-loop system by integrating path planning and control. The closed-loop system is represented as a discrete linear time-varying system and its stability is proved using the Lyapunov stability theorem. In the proposed system, we also see that a numerical singularity problem may incur, which could bring undesirable steering. To avoid numerical singularity, we also propose a virtual towing method. From numerical simulations, we show that the vehicle converges smoothly to the parking spot.

To model static shapes in the plane, the ancient Greeks introduced Euclidean geometry. To model motion, on the other hand, Newton added a new time axis, perpendicular to the plane. This may help model a force, applied to an object from the outside to accelerate its original motion.

Large elongated single crystals (2.91 mm × 97 μm) of 1,6-dibromopyrene were successfully obtained from solution using the slow evaporation method. Their carrier mobility was obtained via current–voltage characteristics of bottom-gate bottom-contact-type field-effect transistors. In these devices, the longitudinal direction of each crystal was parallel or perpendicular to the conductive channel. The highest mobility was 6.0 × 10−4 cm2 V−1 s−1 and 2.2 × 10−3 cm2 V−1 s−1 in the linear and saturation region, respectively, when the electric current flowed across the crystal’s longitudinal direction. The emission strength ratio and mobility ratio between the two longitudinal directions (parallel and perpendicular to the conductive channel, respectively) were 3.1 and 2.2. X-ray diffraction measurements suggested that both the emission strength and mobility are larger in the transverse intermolecular contact direction than in the stacking direction. The mobilities in the linear region were tentatively corrected by subtracting the contributions of charge injection barriers and were estimated to be 2.1–2.9 times larger than the uncorrected ones. The results of this study suggest that bromine substitution is one of the effective methods to modify the optical properties and improve the solution processability of organic semiconductor materials while maintaining the carrier mobility.

This paper focuses on transverse crack detection and its depth estimation in the shaft by applying extrinsic excitation for an overhung rotating shaft system. The dynamics of overhung rotating shaft system with six different shafts having different crack depth parameters are studied experimentally and through the finite element method (FEM). Variation of natural frequencies with crack depth parameters is studied using FEM through ANSYS. The practical application of axial extrinsic excitation is employed to an overhung rotating shaft system for spectrum analysis in two mutually perpendicular directions. The comparison of spectrum for healthy and cracked overhung rotating shaft system shows the appearance of distinctive peaks for cracked rotor system along with 2X component which is major for crack detection. The appearance of peaks at the summation of extrinsic excitation frequency plus rotational frequency along with extrinsic excitation frequency and its harmonics provides an early warning of the crack in the rotor system. The amplitude of these peaks also increases with the crack depth parameter, which estimates crack depth in the shaft. The approach presented in this paper can be very well adapted for crack detection and estimate its depth in the overhung rotating shaft system during its operation.

Due to the stringent requirements of carbon emissions, traditional cutting using a large amount of mineral-based metal cutting fluid for lubrication no longer fulfilled the rigorous requirements of policies and standards. Nanofluid minimum quantity lubrication has been proven to be a new process to achieve clean manufacturing. However, due to adhesive contact friction, lubricant droplets cannot effectively penetrate the tool and workpiece interface during continuous turning. Changing the microstructure of the rake face of the tool, such as the micro-texture, may provide a geometric channel for the diffusion of the lubricant. However, the effects of micro-texture geometry and arrangement on the film formation and tribological properties of droplets have not been revealed yet. The spreading behavior of minimum quantity lubrication atomized microdroplet on the textured surface was calculated by hydrodynamic modeling. It was proven that the microchannel can effectively store the lubricating medium atomized by compressed air pneumatics. Furthermore, a comparative experiment was conducted on the influence of the texture arrangement on the cutting performance through the turning experiment. Results show that the microgrooves in the direction perpendicular to the main cutting edge obtained the lowest cutting force. The feed force, radial force, and tangential force were reduced by 13.46%, 16.23%, and 6.34%, respectively. Meanwhile, the texture arranged parallel to the cutting edge and crosswise increased the cutting force. The arrangement of the texture perpendicular to the main cutting edge direction obtained the optimal workpiece surface, the smallest chip curling radius, and the smoothest chip surface. Under the optimized texture arrangement, the anti-wear and anti-friction properties of nanofluids in the cutting area are enhanced.

Finger joint is an established technique to connect small timber pieces in axial direction, creating timber with theoretical infinite length. This study was undertaken to determine the major failure modes and compression strength properties of finger joints in seven Sri Lankan timber species. Two finger lengths (13 mm and 19 mm) were used for experimental analysis on failure modes and compressive tests. Major failure modes of the finger-jointed specimens subjected to compression parallel to grain test are crushing, splitting, shearing and end rolling. Crushing, splitting, and wrinkling are shown in the specimens of compression perpendicular to grain. Significant relationships were observed between density and compression tests of clear and finger-jointed specimens.

To explore the mechanism of formation and methods of control of edge burr in the grinding and forming of cemented carbide micro-drill, the morphology, material composition, and the edge structure of the generated area of the edge burrs are studied. Through indentation and scratch experiments, the critical grinding depth (hc) of grinding machining is calculated to be 0.793–1.052 μm. The grinding experiments have verified the effects of the actual grinding depth h0 of different single abrasive particles on the edge burr and the effectiveness of the method of controlling the burr by increasing the cutting angle of the abrasive particles. The experimental results show that edge burrs are mainly concentrated on the cutting edge close to the outer cylinder of the micro-drill. When the actual grinding depth h0 of a single abrasive particle is less than the critical grinding depth hc, workpiece material is mainly subjected to plastic deformation removal, the length L of the edge burr along the edge direction is 10–20 μm, the width W of the burr perpendicular to the edge direction is 1–3 μm. The formation of edge burrs is mainly related to the actual grinding depth and the abrasive grain cutting angle γ of abrasive grains. With the increase of h0, the length L of the edge burr decreases, and the width W thereto first increases, then decreases. Increasing the cutting angle of abrasive particles can control the edge burr. By changing the grinding direction of the grinding wheel, the cutting angle of the abrasive particles can be changed from an acute angle to an obtuse angle, thereby eliminating the edge burr without affecting the performance of micro-drilling.

In this work, SEM images analysis and fractal dimension calculations are performed on the fracture surfaces for N50-type with low coercivity, 30 EH-type with high coercivity, and isotropic Nd-Fe-B permanent magnets. It is discovered for the first time that the difference between the fractal dimensions of fracture surface parallel and perpendicular to the c-axis D ∥ and D ⊥ for N50-type magnet with low coercivity is large, and the difference between the fractal dimensions of D ∥ and D ⊥ for 30 EH-type magnet with high coercivity is small. However, there is almost no difference in the fractal dimension of D ∥ and D ⊥ for isotropic magnet. The correlation between anisotropic fractal dimension of the fracture surface and coercivity is revealed. The difference between the fractal dimension of fracture surface D ∥ and D ⊥ not only reflects the difference in micro morphology, but also serves as an important performance parameter to characterize the coercivity of the magnet, which provides new insights for studying the relationship between the magnetic properties and the microstructure of permanent magnetic materials.

A low-loss all-straight optical fiber vector magnetic field sensor (OFVMS) based on magnetic fluid (MF) is designed and proposed. The sensing structure is composed of a Section of the C-type optical fiber (CTF) embedded in a pair of multi-mode optical fibers (MMF) and wrapped in a capillary with MF. The asymmetry of the CTF provides support for the vector magnetic field measurement whose direction is perpendicular to the optical transmission direction. According to the results of experiments, it can be obtained that the refractive index (RI) sensitivity of the sensing structure is as high as −15716.6072 nm/RIU. In addition, the intensity sensitivity of the OFVMS in the calibrated 90° direction can reach 202.23 pm/G between 0 and 123 G. At the same time, the transmission loss of the proposed sensor structure is not increased by the filling of MF. The sensor demonstrated has dominance in low cost, easy manufacture, and lower loss compared with the same type of sensor device, which has application prospects in vector magnetic field sensing.

A miniature wide-range three-axis vector atomic magnetometer under spin-exchange relaxation-free regime has been developed. With a cylindrical vapor cell of size 10 mm in diameter and length, we have constructed a single-beam configuration through a polarization-maintaining fiber carrying the laser beam to the sensor and a multimode fiber guiding the transmitted light field to the photodiode. A rotating field on the plane perpendicular to the direction of propagation of the laser and another modulation field in the pump direction, which are generated in the field programmable gate array using direct digital synthesis to measure the three components of the magnetic field simultaneously. The spin-exchange relaxation is suppressed in zero field controlled by a feedback system, thus a wide range and excellent accuracy of three-axis vector atomic magnetometer response is obtained. Consequently, the transverse magnetic field sensitivity of 350 fT/Hz1/2 and longitudinal field sensitivity of 3pT/Hz1/2 are achieved with a dynamic range of 60000 nT. This sensor with compact size, wide range and high sensitivity is particularly suitable for geomagnetic observatory and space exploration.

This paper reports a discovery of novel morphological features of ZnO asymmetric micron-sized single crystals synthesized by microwave irradiation of W/O emulsions containing a Zn source in the inner aqueous phase. The influence of the zinc ion concentration on the size and shape is studied in detail. The morphological and structural properties show that the obtained ZnO powders are almost mono-dispersed ZnO single crystals with a novel morphology of truncated hexagonal pyramids ca. 1 μm in diameter. A scanning precession electron diffraction analysis reveals that the asymmetrically shaped ZnO single crystals thus obtained have a crystallographic c-axis perpendicular to the bottom hexagonal flat surfaces, and annular bright-field imaging indicates that the bottom surfaces are Zn-terminated ZnO(0001)-Zn polar faces. These new findings are led from a combination of well-controllable liquid-phase emulsion synthesis of the oxide powders and highly advanced atomic-resolution TEM imaging technique, suggesting for the first time a highly probable relationship between the polarity of the wurtzite-type crystal structure and the novel asymmetric morphology of the ZnO microcrystals obtained in this study.