Remote Cell Growth Sensing Using Self-Sustained Bio-Oscillations

A smart sensor system for cell culture real-time supervision is proposed, allowing for a significant reduction in human effort applied to this type of assay. The approach converts the cell culture under test into a suitable “biological” oscillator. The system enables the remote acquisition and management of the “biological” oscillation signals through a secure web interface. The indirectly observed biological properties are cell growth and cell number, which are straightforwardly related to the measured bio-oscillation signal parameters, i.e., frequency and amplitude. The sensor extracts the information without complex circuitry for acquisition and measurement, taking advantage of the microcontroller features. A discrete prototype for sensing and remote monitoring is presented along with the experimental results obtained from the performed measurements, achieving the expected performance and outcomes

Piezoelectric vibration energy harvesting from airflow in HVAC (Heating Ventilation and Air Conditioning) systems

This study focuses on the design and wind tunnel testing of a high efficiency Energy Harvesting device, based on piezoelectric materials, with possible applications for the sustainability of smart buildings, structures and infrastructures. The development of the device was supported by ESA (the European Space Agency) under a program for the space technology transfer in the period 2014-2016. The EH device harvests the airflow inside Heating, Ventilation and Air Conditioning (HVAC) systems, using a piezoelectric component and an appropriate customizable aerodynamic appendix or fin that takes advantage of specific airflow phenomena (vortex shedding and galloping), and can be implemented for optimizing the energy consumption inside buildings. Focus is given on several relevant aspects of wind tunnel testing: different configurations for the piezoelectric bender (rectangular, cylindrical and T-shaped) are tested and compared, and the effective energy harvesting potential of a working prototype device is assessed

An Assessment of PIER Electric Grid Research 2003-2014 White Paper

This white paper describes the circumstances in California around the turn of the 21st century that led the California Energy Commission (CEC) to direct additional Public Interest Energy Research funds to address critical electric grid issues, especially those arising from integrating high penetrations of variable renewable generation with the electric grid. It contains an assessment of the beneficial science and technology advances of the resultant portfolio of electric grid research projects administered under the direction of the CEC by a competitively selected contractor, the University of California’s California Institute for Energy and the Environment, from 2003-2014

An FPGA Noise Resistant Digital Temperature Sensor with Auto Calibration

In recent years, thermal sensing in digital devices has become increasingly important. From a security perspective, new thermal-based attacks have revealed vulnerabilities in digital devices. Traditional temperature sensors using analog-to-digital converters consume significant power and are not conducive to rapid development. As a result, there has been an escalating demand for low cost, low power digital temperature sensors that can be seamlessly integrated onto digital devices. This research seeks to create a modular Field Programmable Gate Array digital temperature sensor with auto one-point calibration to eliminate the excessive costs and time associated with calibrating existing digital temperature sensors. In addition, to support the auxiliary protection role, the sensor is evaluated alongside a RSA circuit implemented on the same chip, with methods developed to mitigate noise and power fluctuations introduced by the main circuit. The result is a digital temperature sensor resistant to noise and suitable for quick mass deployment in digital devices

Piezoelectric energy harvesting from low frequency and random excitation using frequency up-conversion

The field of energy harvesting comprises all methods to produce energy locally and from surrounding sources, e.g. solar illumination, thermal gradients, vibration, radio frequency, etc. The focus of this thesis is on inertial power generation from host motion, in particular for low frequency and random excitation sources such as the human body. Under such excitation, the kinetic energy available to be converted into electrical energy is small and conversion efficiency is of utmost importance. Broadband harvesting based on frequency tuning or on non-linear vibrations is a possible strategy to overcome this challenge. The technique of frequency up-conversion, where the low frequency excitation is converted to a higher frequency that is optimal for the operation of the transducer is especially promising. Regardless of the source excitation, energy is converted more efficiently. After a general introduction to the research area, two different prototypes based on this latter principle and using piezoelectric bending beams as transducers are presented, one linear design and one rotational. Especially for human motion, the advantages of rotational designs are discussed. Furthermore, magnetic coupling is used to prevent impact on the brittle piezoceramic material when actuating. A mathematical model, combining the magnetic interaction forces and the constitutive mechanical and electrical equations for the piezoelectric bending beam is introduced and the results are provided. Theoretical findings are supported by experimental measurements and the calculation model is validated. The outcome is the successful demonstration of a rotational energy harvester, tested on a custom made shaking set-up and in the real world when worn on the upper arm during running.Open Acces

Telemonitoring systems for respiratory patients: technological aspects.

Abstract This review introduces the reader to the available technologies in the field of telemonitoring, with focus on respiratory patients. In the materials and methods section, a general structure of telemonitoring systems for respiratory patients is presented and the sensors of interest are illustrated, i.e., respiratory monitors (wearable and non-wearable), activity trackers, pulse oximeters, environmental monitors and other sensors of physiological variables. Afterwards, the most common communication protocols are briefly introduced. In the results section, selected clinical studies that prove the significance of the presented parameters in chronic respiratory diseases are presented. This is followed by a discussion on the main current issues in telemedicine, in particular legal aspects, data privacy and benefits both in economic and health terms

Integration of aero-elastic belt into the built environment for low-energy wind harnessing: current status and a case study

Low-powered devices are ubiquitous in this modern age especially their application in the urban and built environment. The myriad of low-energy applications extend from wireless sensors, data loggers, transmitters and other small-scale electronics. These devices which operate in the microWatt to milliWatt power range and will play a significant role in the future of smart cities providing power for extended operation with little or no battery dependence. Low energy harvesters such as the aero-elastic belt are suitable for integration with wireless sensors and other small-scale electronic devices and therefore there is a need for studying its optimal installation conditions. In this work, a case study presenting the Computational Fluid Dynamics modelling of a building integrated with aero-elastic belts (electromagnetic transduction type) was presented. The simulation used a gable-roof type building model with a 27° pitch obtained from the literature. The atmospheric boundary layer flow was employed for the simulation of the incident wind. The work investigates the effect of various wind speeds and aero-elastic belt locations on the performance of the device giving insight on the potential for integration of the harvester into the built environment. The apex of the roof of the building yielded the highest power output for the aero-elastic belt due to flow speed-up maximisation in this region. This location produced the largest power output under the 45° angle of approach, generating an estimated 62.4 mW of power under accelerated wind in belt position of up to 6.2 m/s. For wind velocity of 10 m/s, wind in this position accelerated up to approximately 14.4 m/s which is a 37.5% speed-up at the particular height. This occurred for an oncoming wind 30° relative to the building facade. For velocity equal to 4.7 m/s under 0° wind direction, airflows in facade edges were the fastest at 5.4 m/s indicating a 15% speed-up along the edges of the building