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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Automotive Energy Harvesting

Haugen, Petter January 2019 (has links)
Vibration measurements conducted in three vehicles windshields are used to determine frequency content in the windshield of moving vehicles. A piezoelectric energy harvester is modeled, and used in simulations to determine output voltage and power with measured acceleration signal as input.
412

Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams

Mirzaabedini, Sohrab 12 1900 (has links)
The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
413

BIOELECTRICITY INSPIRED POLYMER ELECTROLYTE MEMBRANES FOR SENSING AND ENGERGY HARVESTING APPLICATIONS

Cao, Jinwei January 2018 (has links)
No description available.
414

Design and Finite Element Modeling of a MEMS‐scale Aluminum Nitride (AlN) EnergyHarvester with Meander Spring Feature

Zula, Daniel Peter 28 August 2019 (has links)
No description available.
415

Analyzing and Exploiting the Dynamics of Complex Piecewise-Linear Nonlinear Systems

Tien, Meng-Hsuan 01 October 2020 (has links)
No description available.
416

Functionalized Cellulose Fibers for Smart Textile

Pengfei Deng (16801794) 09 August 2023 (has links)
<p>Smart textiles, characterized by their ability to sense and react to various environmental stimuli, represent an evolution beyond conventional textiles, with wide-ranging applications across healthcare, sports, fashion, and defense sectors. However, the prevalent use of synthetic, petroleum-based fibers in the production of these textiles presents significant environmental and sustainability challenges. This thesis addresses this concern by exploring the functionalization of cellulose fibers—a biodegradable and renewable resource—for use in smart textiles.</p><p>The central objective of this research is to develop methodologies for the functionalization of cellulose fibers that can impart them with the requisite properties. We have developed a smart textile with integrated sensor networks and self-powering units, which features excellent stretchability, bendability, washability, and comfort, without additional uncomfortable, bulky, and rigid power sources. Via a facile infiltration process, an active polymer-based semiconductor is incorporated into the primary thread and textile towards the realization of a high-performance, self-powered biaxial motion detection, and sensing network.</p><p>The results demonstrate that, through strategic functionalization, cellulose fibers can indeed be transformed into smart materials, effectively integrating the benefits of interactive textiles with the sustainability of cellulose. By bridging the gap between sustainability and functionality, this thesis points towards a future where the textile industry can thrive on the intersection of ecological responsibility and technological innovation.</p>
417

System Design of Composite Thermoelectrics for Aircraft Energy Harvesting

Mativo, John M. January 2020 (has links)
No description available.
418

Vibration-Based Energy Harvesting with Essential Non-Linearities

Triplett, Angela Lynn 02 December 2011 (has links)
No description available.
419

RF Energy Harvesting for Implantable ICs with On-chip Antenna

Liu, Yu-Chun 01 January 2014 (has links)
Nowadays, as aging population increasing yearly, the health care technologies for elder people who commonly have high blood pressure or Glaucoma issues have attracted much attention. In order to care of those people, implantable integrated circuits (ICs) in human body are the direct solution to have 24/7 days monitoring with real-time data for diagnosis by patients themselves or doctors. However, due to the small size requirement for the implanted ICs located in human organs, it's quite challenging to integrate with transmitting and receiving antenna in a single chip, especially operating in 5.8-GHz ISM band. This research proposes a new idea to solve the issue of integrating an on-chip antenna with implanted ICs. By adding an additional dielectric substrate upon the layer of silicon oxide in CMOS technology, utilizing the metal-6, it can form an extremely compact 3D-structure on-chip antenna which is able to be placed in human eye, heart or even in a few mm-diameter vessels. The proposed 3D on-chip antenna is only 1x1x2.8 mm3 with -10 dB gain and 10% efficiency, which has capability to communicate at least within 5 cm distance. The entire implanted battery-less wireless system has also been developed in this research. A designed 30% efficiency Native NMOS rectifier could generate 1 V and 1 mA to supply the designed low power transmitter including voltage-controlled oscillator (VCO) and power amplifier (PA). The entire system performance is well evaluated by link budget analysis and the simulation result demonstrates the possibility and feasibility of future on-demand easy-to-design implantable SoC.
420

A Wide Input Power Line Energy Harvesting Circuit For Wireless Sensor Nodes

Wang, Jinhua January 2021 (has links)
Massive deployment of wireless IoT (Internet of Things) devices makes replacement or recharge of batteries expensive and impractical for some applications. Energy harvesting is a promising solution, and various designs are proposed to harvest power from ambient resources including thermal, vibrational, solar, wind, and RF sources. Among these ambient resources, AC powerlines are a stable energy source in an urban environment. Many researchers investigated methods to exploit this stable source of energy to power wireless IoT devices. The proposed circuit aims to harvest energy from AC powerlines with a wide input range of from 10 to 50 A. The proposed system includes a wake-up circuit and is capable of cold-start. A buck-boost converter operating in DCM is adopted for impedance matching, where the impedance is rather independent of the operation conditions. So, the proposed system can be applied to various types of wireless sensor nodes with different internal impedances. Experimental results show that the proposed system achieves an efficiency of 80.99% under the powerline current of 50 A. / M.S. / Nowadays, with the magnificent growth of IoT devices, a reliable, and efficient energy supply system becomes more and more important, because, for some applications, battery replacement is very expensive and sometimes even impossible. At this time, a well-designed self-contained energy harvesting system is a good solution. The energy harvesting system can extend the service life of the IoT devices and reduce the frequency of charging or checking the device. In this work, the proposed circuit aims to harvest energy from the AC power lines, and the harvested power intends to power wireless sensor nodes (WSNs). By utilizing the efficient and self-contained EH system, WSNs can be used to monitor the temperature, pressure, noise level and humidity etc. The proposed energy harvesting circuit was implemented with discrete components on a printed circuit board (PCB). Under a power line current of 50 A @ 50 Hz, the proposed energy harvesting circuit can harvest 156.6 mW, with a peak efficiency of 80.99 %.

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