We present the theory of eclipsing a rotating, spatially extended source of directional emission by a central absorber, and apply it to the pulsar magnetosphere. The theory assumes the radially extended inward radio emission along the local direction of magnetic field, and the pulsar as the absorber. Geometry of magnetic field lines of the rotating dipole is favourable for the double eclipse ev...

Waves of any kinds, including sound waves and light waves, can interfere constructively or destructively when they are overlapped, allowing for myriad applications. However, unlike continuous waves of a single frequency, interference of photoacoustic pulses is often overlooked because of their broadband characteristics and short pulse durations. Here, we study cancellation of two symmetric phot...

In this article, a range of problems and theories will be introduced that will build towards a new wave energy converter (WEC) concept, with the acronym 'ROTA' standing for resonant over-topping absorber. First, classical results for wave power absorption for WECs constrained to operate in a single degree of freedom will be reviewed and the role of resonance in their operation highlighted. Emph...

This paper describes third aircraft model with 2 degrees of freedom. The aim of this study is to develop a mathematical model for investigation of adoptable landing gear vibration behavior and to design Proportional Integration Derivative (PID) classical techniques for control of active hydraulic nonlinear actuator. The parameters of controller and suspension system are adjusted according to be...

This paper reports high performance flexible Lamb wave humidity sensors with a graphene oxide sensing layer. The devices were fabricated on piezoelectric ZnO thin films deposited on flexible polyimide substrates. Two resonant peaks, namely the zero order antisymmetric (A0) and symmetric (S0) mode Lamb waves, were observed and fitted well with the theoretical analysis and modelling. With graphen...

Far-infrared to millimeter-wave bolometers designed to make astronomical observations are typically encased in integrating cavities at the termination of feedhorns or Winston cones. This photometer combination maximizes absorption of radiation, enables the absorber area to be minimized, and controls the directivity of absorption, thereby reducing susceptibility to stray light. In the next decad...

In the biped robotics domain, head oscillations may be extremely harmful, especially if robot is teleoperated, since vibrations strongly reduce operator’s spatial awareness. particular, undesired occur in under-actuated robots, where springs and passive mechanisms are used to achieve a human-like motion. This paper proposes an approach of robot’s head; proposed solution does not affect dynamic ...

In this paper, the possible realization of the electromagnetic (EM) absorber as a thin metasurface is considered. The metasurface is based on establishing a passive surface of electric and magnetic currents using the Huygen’s principle. So, the absorber is named Huygens Absorber (HA). The metasurface can be designed using split meander lines with spiral rings. In this way, both sides of the sub...

This is a theoretical, numerical, and experimental study on the vibration attenuation capability of dynamic response building-like structure using absorber in cantilever flexible beam configuration, taking into account gravitational effects associated with its mass. The model primary vibrating passive control device obtained Euler–Lagrange formulation considering as generalized system one degre...