TY - JOUR A1 - Burdin, Dmitrii A. A1 - Ekonomov, Nikolai A. A1 - Chashin, Dmitri V. A1 - Fetisov, Leonid Y. A1 - Fetisov, Yuri K. A1 - Shamonin (Chamonine), Mikhail T1 - Temperature Dependence of the Resonant Magnetoelectric Effect in Layered Heterostructures JF - Materials N2 - The dependence of the resonant direct magnetoelectric effect on temperature is studied experimentally in planar composite structures. Samples of rectangular shapes with dimensions of 5 mm x 20 mm employed ferromagnetic layers of either an amorphous (metallic glass) alloy or nickel with a thickness of 20-200 m and piezoelectric layers of single crystalline langatate material or lead zirconate titanate piezoelectric ceramics with a thickness of 500 m. The temperature of the samples was varied in a range between 120 and 390 K by blowing a gaseous nitrogen stream around them. It is shown that the effective characteristics of the magnetoelectric effectsuch as the mechanical resonance frequency f(r), the quality factor Q and the magnitude of the magnetoelectric coefficient (E) at the resonance frequencyare contingent on temperature. The interrelations between the temperature changes of the characteristics of the magnetoelectric effect and the temperature variations of the following material parametersYoung's modulus Y, the acoustic quality factor of individual layers, the dielectric constant epsilon, the piezoelectric modulus d of the piezoelectric layer as well as the piezomagnetic coefficients ((n)) of the ferromagnetic layerare established. The effect of temperature on the characteristics of the nonlinear magnetoelectric effect is observed for the first time. The results can be useful for designing magnetoelectric heterostructures with specified temperature characteristics, in particular, for the development of thermally stabilized magnetoelectric devices. KW - acoustic quality factor KW - composite structure KW - linear KW - magnetoelectric effect KW - magnetoelectric heterostructure KW - magnetostriction KW - nonlinear KW - piezoelectric KW - temperature dependence Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-32185 N1 - corresponding author: Mikhail Shamonin VL - 10 IS - 10 PB - MDPI ER - TY - JOUR A1 - Dechant, Eduard A1 - Fedulov, Feodor A1 - Fetisov, Leonid Y. A1 - Shamonin (Chamonine), Mikhail T1 - Bandwidth Widening of Piezoelectric Cantilever Beam Arrays by Mass-Tip Tuning for Low-Frequency Vibration Energy Harvesting JF - Applied Science N2 - Wireless sensor networks usually rely on internal permanent or rechargeable batteries as a power supply, causing high maintenance efforts. An alternative solution is to supply the entire system by harvesting the ambient energy, for example, by transducing ambient vibrations into electric energy by virtue of the piezoelectric effect. The purpose of this paper is to present a simple engineering approach for the bandwidth optimization of vibration energy harvesting systems comprising multiple piezoelectric cantilevers (PECs). The frequency tuning of a particular cantilever is achieved by changing the tip mass. It is shown that the bandwidth enhancement by mass tuning is limited and requires several PECs with close resonance frequencies. At a fixed frequency detuning between subsequent PECs, the achievable bandwidth shows a saturation behavior as a function of the number of cantilevers used. Since the resonance frequency of each PEC is different, the output voltages at a particular excitation frequency have different amplitudes and phases. A simple power-transfer circuit where several PECs with an individual full wave bridge rectifier are connected in parallel allows one to extract the electrical power close to the theoretical maximum excluding the diode losses. The experiments performed on two- and three-PEC arrays show reasonable agreement with simulations and demonstrate that this power-transfer circuit additionally influences the frequency dependence of the harvested electrical power. KW - array KW - BAND-PASS FILTERS KW - bandwidth KW - BIMORPH KW - Optimization KW - OUTPUT KW - PERFORMANCE KW - piezoelectric cantilever KW - POWER KW - vibration energy harvesting Y1 - 2017 U6 - https://doi.org/10.3390/app7121324 N1 - Corresponding Author: Mikhail Shamonin VL - 7 IS - 12 PB - MDPI ER - TY - JOUR A1 - Diamantidis, Dimitris T1 - A Critical View on Environmental and Human Risk Acceptance Criteria JF - International Journal of Environmental Science and Development N2 - Natural and technological hazards have a major impact on environmental and human safety. Risk assessment plays an essential role in the risk management of the effects of such hazards. This contribution summarizes first the general formulation of risk depending on two parameters: hazard probability and associated consequences. Problems faced in industrial applications based on the experience of the author are discussed. Risk acceptance criteria for the contributors to risk i.e. human, economic and environment are critically reviewed. Resilience based criteria are also included and conclusions for future developments are provided. KW - Environmental risk KW - human risk KW - Risk acceptance KW - Risk analysis KW - safety measures Y1 - 2017 U6 - https://doi.org/10.18178/ijesd.2017.8.1.921 N1 - Corresponding author: Dimitris Diamantidis VL - 8 IS - 1 SP - 62 EP - 66 ER - TY - JOUR A1 - Altmann, Matthias A1 - Schlegl, Peter A1 - Volbert, Klaus T1 - A low-power wireless system for energy consumption analysis at mains sockets JF - EURASIP Journal on Embedded Systems N2 - Introduction: Improving energy efficiency and reducing energy wastage is an important topic of our time. But it is quite difficult to figure out how much of our total electricity bill can be mapped to which device or at what time the device used it. We believe energy efficiency of normal households can be improved, if this kind of transparency would be available. In this article, we present a system for energy measurement at mains sockets to gain a transparent view of energy consumption for each device in a household. It consists of several smart energy measuring devices (SEMDs) that use a low-power radio protocol to dynamically build and connect to a radio network to transfer power usage date to a server. At the server, the data is stored and can be accessed via web interface. Results: Our primary goal was to build a back-end system for an energy metering platform with very low energy consumption. This platform can provide data for a variety of services that enables users (the consumers) to understand and improve their energy consumption behavior and increase overall energy efficiency of their households. KW - Low power KW - Smart grid KW - Smart home KW - Smart metering KW - Wireless system Y1 - 2017 U6 - https://doi.org/10.1186/s13639-016-0041-y N1 - Corresponding author: Peter Schlegl IS - 1 PB - Springer Nature ER -