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In order to maintain a safe working environment, there is a constant need for the inspection of structures for failure. One common problem faced during inspection is restricted access to the inspection site. Furthermore, inspectors use sensors like cameras and non-destructive testing kits to detect structural failures such as cracks and corrosion. Still, due to the size and complex geometry of most structures, inspection is expensive, time-consuming and potentially unsafe. This paper, therefore, describes the design of a robot that can be used for non-destructive Inspections of various range of structures to improve and automate structural inspections. In order to achieve this aim, different existing robotic designs have been reviewed, with focus on wall-climbing robots in similar environments. The final design combines a set of actuator motors, magnetic tracked wheels to aid vertical movement on magnetic structures, as well as a wireless camera for visual inspection and manoeuvring the robot system for the identification of surface cracks and corrosion using YOLOv4 machine learning algorithm. The structure of the tracks allows the robot to climb over uneven surfaces like bulwark, obstacles etc. which allows inspections in unfriendly and inaccessible environments therefore reducing costs and inspection time considerably. [ABSTRACT FROM AUTHOR]

In order to maintain a safe working environment, there is a constant need for the inspection of structures for failure. One common problem faced during inspection is restricted access to the inspection site. Furthermore, inspectors use sensors like cameras and non-destructive testing kits to detect structural failures such as cracks and corrosion. Still, due to the size and complex geometry of most structures, inspection is expensive, time-consuming and potentially unsafe. This paper, therefore, describes the design of a robot that can be used for non-destructive Inspections of various range of structures to improve and automate structural inspections. In order to achieve this aim, different existing robotic designs have been reviewed, with focus on wall-climbing robots in similar environments. The final design combines a set of actuator motors, magnetic tracked wheels to aid vertical movement on magnetic structures, as well as a wireless camera for visual inspection and manoeuvring the robot system for the identification of surface cracks and corrosion using YOLOv4 machine learning algorithm. The structure of the tracks allows the robot to climb over uneven surfaces like bulwark, obstacles etc. which allows inspections in unfriendly and inaccessible environments therefore reducing costs and inspection time considerably. [ABSTRACT FROM AUTHOR]

MnAs1-xSbx material is one of the ferromagnets which can contribute to a magnetic refrigeration system that is useable at room temperature. The consolidation experiments of MnAs1-xSbx (x = 0.068, 0.073) powder are carried out by a shock compaction method using underwater shock wave with shock pressure of 16 GPa. The magnetic entropy change, ΔSmag, of annealed sample (x = 0.073) after press caused by a magnetic field of 1 T is 27.8 J/Kkg at the maximum value, and the sample annealed after press undergoes a first-order ferromagnetic to paramagnetic transition at 304.05 K. [ABSTRACT FROM AUTHOR]

It is shown that the short-range oscillating spin polarization of conduction electrons around magnetic moment embedded in the superconducting film is screened in aggregate by the long-range antiferromagnetic term, which owes its origin to the Cooper pairing. On this base new exchange model and boundary value problem for the proximity effect in ferromagnet/superconductor (F/S) nanostructures are proposed. In the framework of this model we investigate the possible variants of the mutual accommodation of inhomogeneous superconducting and magnetic order parameters in the F/S nanostructures. The F/S systems of the first type allow only homogeneous ferromagnetic ordering in the F layers, which for the weak exchange fields h < hc coexists with superconductivity in the S layers (FS phase). In the F/S systems of the second type the FS phase exists only for h < hc1. For the exchange fields hc1 < h < hc2 the superconducting layers S induce the nonuniform cryptoferromagnetic modulation (CFS phase) in the spin structure of the F films. This phenomenon can be called as the magnetic (or inverse) proximity effect. The conditions for the coexistence of the inhomogeneous magnetism and superconductivity in the F/S nanostructures EuO/A1, EuO/V, EuS/A1, and LaCaMnO/YBaCuO are investigated and the nontrivial experimental data are interpreted. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have performed 11B-NMR experiments on an easy-plane type ferromagnet VBO3 under magnetic fields of up to 6 T. The absolute value of the shift of the resonance line increases with decreasing temperature and tends to be constant below TC, which is consistent with the magnetization behavior. The hyperfine coupling constant and the quadrupole splitting are estimated. We also found that the relaxation rate T1-1 of 11B decreases as T1-1 ∼ T5 below 50 K, suggesting a spin-wave relaxation process. Further crossover of the dominant relaxation process is suggested at about 8 K. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]