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Physical Sciences and Mathematics Commons

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Engineering

Michigan Technological University

Center for Cyber-Physical Systems

Publication Year

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Spatial Dispersion Of Index Components Required For Building Invisibility Cloak Medium From Photonic Crystals, Saeid Jamilan, George Semouchkin, Navid Gandji, Elena Semouchkina Mar 2018

Spatial Dispersion Of Index Components Required For Building Invisibility Cloak Medium From Photonic Crystals, Saeid Jamilan, George Semouchkin, Navid Gandji, Elena Semouchkina

Michigan Tech Publications

The opportunities to use dielectric photonic crystals (PhCs) as the media of cylindrical invisibility cloaks, designed using transformation optics (TO) concepts, are investigated. It is shown that TO-based prescriptions for radial index dispersion, responsible for turning waves around hidden objects, can be dropped if the PhC media support self-collimation of waves in bent crystals. Otherwise, to provide prescribed anisotropy of index dispersion, it is possible to employ PhCs with rectangular lattices. It is found, however, that at acceptable cloak thicknesses, modifications of crystal parameters do not allow for achieving the prescribed level of index anisotropy. This problem is solved by …


Wearete: A Scalable Wearable E-Textile Triboelectric Energy Harvesting System For Human Motion Scavenging, Xian Li, Ye Sun Nov 2017

Wearete: A Scalable Wearable E-Textile Triboelectric Energy Harvesting System For Human Motion Scavenging, Xian Li, Ye Sun

Michigan Tech Publications

In this paper, we report the design, experimental validation and application of a scalable, wearable e-textile triboelectric energy harvesting (WearETE) system for scavenging energy from activities of daily living. The WearETE system features ultra-low-cost material and manufacturing methods, high accessibility, and high feasibility for powering wearable sensors and electronics. The foam and e-textile are used as the two active tribomaterials for energy harvester design with the consideration of flexibility and wearability. A calibration platform is also developed to quantify the input mechanical power and power efficiency. The performance of the WearETE system for human motion scavenging is validated and calibrated …


All-Dielectric Metamaterials: Irrelevance Of Negative Refraction To Overlapped Mie Resonances, Navid Gandji, George Semouchkin, Elena Semouchkina Oct 2017

All-Dielectric Metamaterials: Irrelevance Of Negative Refraction To Overlapped Mie Resonances, Navid Gandji, George Semouchkin, Elena Semouchkina

Michigan Tech Publications

All-dielectric metamaterials comprised of identical resonators draw a lot of attention as low-loss media providing for negative refraction, which is commonly attributed to the double negativity of effective material parameters caused by overlapping of Mie resonances. We study dispersion diagrams of such metamaterials composed of dielectric rod arrays and show that bandwidths of positive and negative refraction and its type are irrelevant to the negativity of effective parameters; instead, they are unambiguously defined by the shape and the location of the second transmission branch in dispersion diagrams and thus can be controlled by the lattice constants.


Harmonic Distortion Minimization In Power Grids With Wind And Electric Vehicles, Ritam Misra, Sumit Paudyal, Oguzhan Ceylan, Paras Mandal Jul 2017

Harmonic Distortion Minimization In Power Grids With Wind And Electric Vehicles, Ritam Misra, Sumit Paudyal, Oguzhan Ceylan, Paras Mandal

Michigan Tech Publications

Power-electronic interfacing based devices such as wind generators (WGs) and electrical vehicles (EVs) cause harmonic distortions on the power grid. Higher penetration and uncoordinated operation of WGs and EVs can lead to voltage and current harmonic distortions, which may exceed IEEE limits. It is interesting to note that WGs and EVs have some common harmonic profiles. Therefore, when EVs are connected to the grid, the harmonic pollution EVs impart onto the grid can be reduced to some extent by the amount of wind power injecting into the grid and vice versa. In this context, this work studies the impact of …


Optimal Scheduling Of Pev Charging/Discharging In Microgrids With Combined Objectives, Chong Cao, Ming Cheng, Bo Chen Apr 2016

Optimal Scheduling Of Pev Charging/Discharging In Microgrids With Combined Objectives, Chong Cao, Ming Cheng, Bo Chen

Michigan Tech Publications

While renewable power generation and vehicle electrification are promising solutions to reduce greenhouse gas emissions, it faces great challenges to effectively integrate them in a power grid. The weather-dependent power generation of renewable energy sources, such as Photovoltaic (PV) arrays, could introduce significant intermittency to a power grid. Meanwhile, uncontrolled PEV charging may cause load surge in a power grid. This paper studies the optimization of PEV charging/discharging scheduling to reduce customer cost and improve grid performance. Optimization algorithms are developed for three cases: 1) minimize cost, 2) minimize power deviation from a pre-defined power profile, and 3) combine objective …