Three-dimensional metamaterial for wave attenuation, unit cell of a three-dimensional metamaterial, method for manufactering of a metamaterial, computer program for 3d printing a metamaterial

The present invention relates to a three-dimensional metamaterial capable of attenuating acoustic waves and mechanical vibrations in broad low-frequency ranges. The three-dimensional metamaterial comprises multiple unit cells that form a three-dimensional lattice. The unit cells each comprise a central part and six satellite parts that are equally distributed around the central part. Each unit cell is connected to the central part by at least one corresponding connector. The invention further relates to a unit cell of a three-dimensional metamaterial capable of attenuating acoustic waves and mechanical vibrations in broad low-frequency ranges

Multi-Frequency Acoustic Steering in Rationally Pruned Disordered Networks

The frequency of a wave is a crucial parameter to understanding its propagation to a structured medium. While metamaterials can be designed to focus or steer deformations or waves toward a specific location, wave steering toward multiple targeted locations at different frequencies remains challenging. Here we show that pruning of random elastic networks allows realizing such multi-objective, multi-frequency acoustic steering. Our study opens up a viable route to the rational design of multi-frequency acoustic metamaterials

Programmable shape-morphing of rose-shaped mechanical metamaterials

Shape morphing is one of the most attractive functionalities of materials that are desired in many applications, including robotic grippers, medical stents, wearable electronics, and so on. Shape morphing can be implemented by using mechanical metamaterials that combine building blocks with properly designed mechanical or material properties. The design approaches are, however, mostly ad hoc or require materials with special properties. This work proposes two automated design strategies for programmable shape morphing and validates them on structures 3D-printed from a widely available commercial Stereolithography Durable resin. We proposed a so-called rose-shaped metamaterial with reduced stress concentration due to the absence of sharp corners and with a large range of tailorable Poisson’s ratios, from −0.5 to 0.9, governed by a single design parameter. We programmed the shape of the rose-shaped metamaterial sheets aiming at high shape comfortability or uniform effective stiffness. The shape-morphing performance is demonstrated in the linear (0.1% strain) and non-linear (20% strain) deformation regimes, and it agrees well with the tensile test results. Our findings show the potential to develop complex practical metamaterial structures at comparatively low costs

Interactive methods of teaching in classes of basic medical and biological sciences

Interactive learning is widely used in more than 115 countries around the world. It has already gained recognition in a relatively short period of time. The main methodological innovations today are connected with the use of interactive teaching methods and techniques when almost all the students are involved in a process of learning, each of whom makes their individual contribution to the solution of the task through the exchange of knowledge and ideas. The widespread introduction of innovative methods in the study of pharmacology and microbiology at the departments of Dnipropetrovsk medical academy is caused by difficulties in studying these subjects traditionally. Among the games in medical universities “Simulation” is preferred. The most common scenario is a "doctor - patient", which reveal questions of clinical manifestations, treatment and prevention of certain diseases, or "concilium", where the focus is on the features of the disease, methods of its diagnosis and choice of treatment and prevention, considering features of pharmacodynamics, pharmacokinetics and side effects of drugs. Tasks for independent work of students on practical lessons can be designed for both, individual and group execution (meaning not only an academic group in general, but also dynamic division into small "creative" or "working" groups / teams). “Contest” game goes well with other progressive teaching methods, such as audio and video demonstration. At studying of medical microbiology demonstration of real objects is often impossible because of their danger to life and health of students, and implementation of a number of laboratory research - because of the complexity and duration. Thus, the benefits of interactive forms of learning are the ability to activate the self-cognitive and mental activity of students, involvement of students in the learning process as active participants in the development of skills in analyzing situations, increased motivation to learn discipline and increase self-esteem in the process of getting positive results, development of skills of teamwork, the increase of independent work of students, the development of proficiency in modern technical equipment and information processing technologies. The use of such forms of work, as the computer testing, provides a more precise objective assessment of students' knowledge and learning to obtain information from different sources and the formation of the needs in this - to get a well trained modern specialist with a high level of qualification

Spider web-structured labyrinthine acoustic metamaterials for low-frequency sound control

AOK has received funding from the European Union’s 7th Framework programme for research and innovation under the Marie Skłodowska-Curie Grant Agreement No. 609402-2020 researchers: Train to Move (T2M).MM has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 658483. NMP is supported by the European Research Council PoC grant 2015 SILKENE No. 693670, EU FETPROACTIVE grant 732344 ‘NEUROFIBRES’, and by the European Commission under the Graphene Flagship (WP14 ‘Polymer Nanocomposites’, No. 604391). FB is supported EU FETPROACTIVE grant 732344 ‘NEUROFIBRES’