Paper-based flexible metamaterial for microwave applications

Metamaterial has become a hotspot in many research fields, including electromagnetism, thermodynamics and mechanics, as it can offers additional design freedom for material to obtain novel properties. Especially for the electromagnetic devices, various interesting electromagnetic properties which cannot be found in nature materials can be realized, such as negative refraction, invisible cloak, etc. Herein, we provide an overview of paper-based metamaterial for microwave application. This work reviews the metamaterial realized on paper substrate, including the fabrication techniques, application fields, as well as the outlook on future directions of the paper-based metamaterial for the readership.

Invisibility Cloak using Color Detection and Segmentation with open CV

Have you ever thought of making visible things invisible, just like the Harry Potter? Have you ever thought how does one supersede backgrounds and add effects in a movie? The cloak was magical and invisible in Harry Potter, the movie. As we know there is no magic and no invisible cloak which exists in the world. It’s all about the graphicstricks. The concept of an invisibility cloak is a mixture of science, fantasy, and the collective imagination. This paper helps to create one’s own ‘Invisibility Cloak’.It will make use of Python and OpenCV module specifically targeting Image Processing and Image Segmentation to create a false sense of invisibility in the frame. It will explore how an object of a specific color or texture can be manipulated using the OpenCV library of python. To achieve this, initially we’ll be capturing and storing the backdrop frame . Thereafter we’ll be identifying the red coloured fabric by making use of the above mentioned algorithms. Then we’ll segment out the red colored fabric by generating a mask and then finallywe’ll generate the final augmented(magical) output to create Invisibility cloak. These steps are discussed deeper in thepaper.

Invisibility Cloak using Color Detection and Segmentation with Open CV

Have you ever thought of making visible things invisible, just like the Harry Potter? Have you ever thought how does one supersede backgrounds and add effects in a movie? The cloak was magical and invisible in Harry Potter, the movie. As we know there is no magic and no invisible cloak which exists in the world. It’s all about the graphics tricks. The concept of an invisibility cloak is a mixture of science, fantasy, and the collective imagination. This paper helps to create one’s own ‘Invisibility Cloak’.It will make use of Python and OpenCV module specifically targeting Image Processing and Image Segmentation to create a false sense of invisibility in the frame. It will explore how an object of a specific color or texture can be manipulated using the OpenCV library of python. To achieve this, initially we’ll be capturing and storing the backdrop frame . Thereafter we’ll be identifying the red coloured fabric by making use of the above mentioned algorithms. Then we’ll segment out the red colored fabric by generating a mask and then finally , we’ll generate the final augmented(magical) output to create Invisibility cloak. These steps are discussed deeper in the paper

Multi-Physics Bi-Functional Intelligent Meta-Device Based on the Shape Memory Alloys

Transformation theory, succeeding in multiple transportation systems, has enlightened researchers to manipulate the field distribution by tailoring the medium’s dominant parameters in certain situations. Therefore, the science community has witnessed a boom in designing metamaterials, whose abnormal properties are induced by artificial structures rather than the components’ characteristics. However, a majority of such meta-devices are restricted to the particular physical regimes and cannot sense the changes taking place in the surrounding environment and adjust its functions accordingly. In this article we propose a multi-physics bi-functional “intelligent” meta-device which can switch its functions between an invisible cloak and a concentrator in both thermal and DC electric conduction as the ambient temperature or voltage varies. The shape memory alloys are utilized in the design to form a moveable part, which plays the crucial role in the switching effect. This work paves the way for a practicable method for obtaining a controllable gradient of heat or electric potential, and also provides guidance for efficiently designing similar intelligent meta-devices by referring to the intriguing property of shape memory alloys.

Role of nanophotonics in the birth of seismic megastructures

The discovery of photonic crystals 30 years ago in conjunction with research advances in plasmonics and metamaterials, has inspired the concept of decameter scale metasurfaces, coined seismic metamaterials for an enhanced control of surface (Love and Rayleigh) and bulk (shear and pressure) elastodynamic waves. These powerful mathematical tools of coordinate transforms, effective medium and Floquet-Bloch theories which have revolutionized nanophotonics, can be translated in the language of civil engineering and geophysics. Experiments on seismic metamaterials made of buried elements in the soil demonstrate that the fore mentioned tools make a possible novel description of complex phenomena of soil-structure interaction during a seismic disturbance. But the concepts are already moving to more futuristic concepts and the same notions developed for structured soils are now used to examine the effects of buildings viewed as above surface resonators in megastructures such as metacities. But this perspective of future should not make us forget the heritage of the ancient peoples. Indeed, we finally point out the striking similarity between an invisible cloak design and the architecture of some ancient megastructures as the antique Gallo-Roman theaters and amphitheatres.