Wearable energy-harvesting micro devices

2016 ◽  
Author(s):  
◽  
Quang Thanh Nhat Nguyen

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The focus of this dissertation is wearable energy-harvesting mircro devices. They are designed to harvest energy from the surrounding environment to supply power on the go for small electronic devices and sensors. We used low-cost and scalable fabrication methods that make them appropriate for mass production processes. There are four devices presented in this manuscript: the paper based ZnO nanogenerator using contact electrification and piezoelectric effects, the Teflon coated thread-shaped contact electrification fiber, the thread-shaped ZnO nanorod piezoelectric body sensor, and the silver nanowire transparent electrode for ZnO/TiO2 core-shell nanoparticle dye-sensitized solar cell. The demand of wearable electronic sensors for health monitoring has been increasing in recent years. However, the primary energy sources for these devices are still batteries that need to be replaced or recharged frequently. These batteries are also bulky and not easily incorporated into a garment. The devices presented in this manuscript are our efforts to address the problem of providing continuous power for wearable devices.

2016 ◽  
Author(s):  
◽  
Zachary Thacker

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Energy collecting antenna have been studied for over a century. Early work performed by Heinrich Hertz and Nikola Tesla focused primarily on the transfer of energy at low frequency electromagnetic waves. The present work studies the possibility for harvesting electromagnetic energy present on earth from both terrestrial and solar sources. In general the energy density available increases with frequency, peaking around the visible portion of the spectrum. Because of the difficulty of converting high frequency signals, the present focus will be on the intermediate Terahertz range where the power density begins to increase. The goal of this work is to support the viability of an energy harvesting rectenna to collect and convert Terahertz frequency electromagnetic energy. The collection of the energy by an antenna is supported through probing frequency dependent material properties required for designing the device. Modelling of materials sensitive to THz waves is confirmed through spectroscopic measurements of fabricated devices. Device design is further supported by showing the relationship between the measured material properties and conversion, or rectification, efficiency. Finally, the concept is proved through quantitative results of THz rectenna measurements.


Author(s):  
H. O. Colijn

Many labs today wish to transfer data between their EDS systems and their existing PCs and minicomputers. Our lab has implemented SpectraPlot, a low- cost PC-based system to allow offline examination and plotting of spectra. We adopted this system in order to make more efficient use of our microscopes and EDS consoles, to provide hardcopy output for an older EDS system, and to allow students to access their data after leaving the university.As shown in Fig. 1, we have three EDS systems (one of which is located in another building) which can store data on 8 inch RT-11 floppy disks. We transfer data from these systems to a DEC MINC computer using “SneakerNet”, which consists of putting on a pair of sneakers and running down the hall. We then use the Hermit file transfer program to download the data files with error checking from the MINC to the PC.


Author(s):  
Gerald B. Feldewerth

In recent years an increasing emphasis has been placed on the study of high temperature intermetallic compounds for possible aerospace applications. One group of interest is the B2 aiuminides. This group of intermetaliics has a very high melting temperature, good high temperature, and excellent specific strength. These qualities make it a candidate for applications such as turbine engines. The B2 aiuminides exist over a wide range of compositions and also have a large solubility for third element substitutional additions, which may allow alloying additions to overcome their major drawback, their brittle nature.One B2 aluminide currently being studied is cobalt aluminide. Optical microscopy of CoAl alloys produced at the University of Missouri-Rolla showed a dramatic decrease in the grain size which affects the yield strength and flow stress of long range ordered alloys, and a change in the grain shape with the addition of 0.5 % boron.


1980 ◽  
Vol 19 (03) ◽  
pp. 125-132
Author(s):  
G. S. Lodwick ◽  
C. R. Wickizer ◽  
E. Dickhaus

The Missouri Automated Radiology System recently passed its tenth year of clinical operation at the University of Missouri. This article presents the views of a radiologist who has been instrumental in the conceptual development and administrative support of MARS for most of this period, an economist who evaluated MARS from 1972 to 1974 as part of her doctoral dissertation, and a computer scientist who has worked for two years in the development of a Standard MUMPS version of MARS. The first section provides a historical perspective. The second deals with economic considerations of the present MARS system, and suggests those improvements which offer the greatest economic benefits. The final section discusses the new approaches employed in the latest version of MARS, as well as areas for further application in the overall radiology and hospital environment. A complete bibliography on MARS is provided for further reading.


Children ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 526
Author(s):  
James Ditai ◽  
Aisling Barry ◽  
Kathy Burgoine ◽  
Anthony K. Mbonye ◽  
Julius N. Wandabwa ◽  
...  

The initial bedside care of premature babies with an intact cord has been shown to reduce mortality; there is evidence that resuscitation of term babies with an intact cord may also improve outcomes. This process has been facilitated by the development of bedside resuscitation surfaces. These new devices are unaffordable, however, in most of sub-Saharan Africa, where 42% of the world’s 2.4 million annual newborn deaths occur. This paper describes the rationale and design of BabySaver, an innovative low-cost mobile resuscitation unit, which was developed iteratively over five years in a collaboration between the Sanyu Africa Research Institute (SAfRI) in Uganda and the University of Liverpool in the UK. The final BabySaver design comprises two compartments; a tray to provide a firm resuscitation surface, and a base to store resuscitation equipment. The design was formed while considering contextual factors, using the views of individual women from the community served by the local hospitals, medical staff, and skilled birth attendants in both Uganda and the UK.


Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 432
Author(s):  
Guenther Retscher ◽  
Alexander Leb

A guidance and information service for a University library based on Wi-Fi signals using fingerprinting as chosen localization method is under development at TU Wien. After a thorough survey of suitable location technologies for the application it was decided to employ mainly Wi-Fi for localization. For that purpose, the availability, performance, and usability of Wi-Fi in selected areas of the library are analyzed in a first step. These tasks include the measurement of Wi-Fi received signal strengths (RSS) of the visible access points (APs) in different areas. The measurements were carried out in different modes, such as static, kinematic and in stop-and-go mode, with six different smartphones. A dependence on the positioning and tracking modes is seen in the tests. Kinematic measurements pose much greater challenges and depend significantly on the duration of a single Wi-Fi scan. For the smartphones, the scan durations differed in the range of 2.4 to 4.1 s resulting in different accuracies for kinematic positioning, as fewer measurements along the trajectories are available for a device with longer scan duration. The investigations indicated also that the achievable localization performance is only on the few meter level due to the small number of APs of the University own Wi-Fi network deployed in the library. A promising solution for performance improvement is the foreseen usage of low-cost Raspberry Pi units serving as Wi-Fi transmitter and receiver.


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