19,829 research outputs found
Development of Economic Water Usage Sensor and Cyber-Physical Systems Co-Simulation Platform for Home Energy Saving
In this thesis, two Cyber-Physical Systems (CPS) approaches were considered to reduce residential building energy consumption. First, a flow sensor was developed for residential gas and electric storage water heaters. The sensor utilizes unique temperature changes of tank inlet and outlet pipes upon water draw to provide occupant hot water usage. Post processing of measured pipe temperature data was able to detect water draw events. Conservation of energy was applied to heater pipes to determine relative internal water flow rate based on transient temperature measurements. Correlations between calculated flow and actual flow were significant at a 95% confidence level. Using this methodology, a CPS water heater controller can activate existing residential storage water heaters according to occupant hot water demand. The second CPS approach integrated an open-source building simulation tool, EnergyPlus, into a CPS simulation platform developed by the National Institute of Standards and Technology (NIST). The NIST platform utilizes the High Level Architecture (HLA) co-simulation protocol for logical timing control and data communication. By modifying existing EnergyPlus co-simulation capabilities, NIST’s open-source platform was able to execute an uninterrupted simulation between a residential house in EnergyPlus and an externally connected thermostat controller. The developed EnergyPlus wrapper for HLA co-simulation can allow active replacement of traditional real-time data collection for building CPS development. As such, occupant sensors and simple home CPS product can allow greater residential participation in energy saving practices, saving up to 33% on home energy consumption nationally
Testing of hydrogen sensor based on organic materials
Práce je zaměřena na problematiku bezpeÄŤnostnĂch vodĂkovĂ˝ch senzorĹŻ. ZákladnĂ principy a teorie vodĂkovĂ˝ch senzorĹŻ je rozebrána v prvnà části práce. Je navrĹľena metodologie testovánĂ organickĂ˝ch vodĂkovĂ˝ch senzorĹŻ vyvinutĂ˝ch a vyrobenĂ˝ch na FakultÄ› ChemickĂ© VysokĂ©ho UÄŤenĂ TechnickĂ©ho v BrnÄ›. NejslibnÄ›jšà organickĂ˝ material byl testován. V závÄ›reÄŤnĂ© části byl navrĹľen teplotnĂ regulátor pro pouĹľitĂ s keramickou senzorovou platformou.This thesis is focused on topic of safety hydrogen sensors. Theory of hydrogen sensors and main sensor principles are discussed. Methodology for testing of organic hydrogen sensors developed and fabricated at the Faculty of Chemistry of Brno University of Technology is outlined. A set of tests is done for the most promising organic material. Also, temperature regulator for ceramic sensor platform is designed.
Model Based Sensor System for Temperature Measurement in R744 Air Conditioning Systems
The goal is the development of a novel principle for the temperature
acquisition of refrigerants in CO2 air conditioning systems. The new approach
is based on measuring the temperature inside a pressure sensor, which is also
needed in the system. On the basis of simulative investigations of different
mounting conditions functional relations between measured and medium
temperature will be derived.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Wireless sensors and IoT platform for intelligent HVAC control
Energy consumption of buildings (residential and non-residential) represents approximately 40% of total world electricity consumption, with half of this energy consumed by HVAC systems. Model-Based Predictive Control (MBPC) is perhaps the technique most often proposed for HVAC control, since it offers an enormous potential for energy savings. Despite the large number of papers on this topic during the last few years, there are only a few reported applications of the use of MBPC for existing buildings, under normal occupancy conditions and, to the best of our knowledge, no commercial solution yet. A marketable solution has been recently presented by the authors, coined the IMBPC HVAC system. This paper describes the design, prototyping and validation of two components of this integrated system, the Self-Powered Wireless Sensors and the IOT platform developed. Results for the use of IMBPC in a real building under normal occupation demonstrate savings in the electricity bill while maintaining thermal comfort during the whole occupation schedule.QREN SIDT [38798]; Portuguese Foundation for Science & Technology, through IDMEC, under LAETA [ID/EMS/50022/2013
A microsensor array for biochemical sensing
A microsensor array to measure chemical properties of biological liquids is presented. A hybrid integration technique is used to mount four sensor chips on a micro flow channel: a pressure, temperature, pH, combined pO2 and pCO2 sensor chip. This results in a microsensor array which is developed to meet the technical requirements for space applications. The integration method allows to integrate other types of sensor chips. This multi-purpose and multi-user approach makes the microsensor array suitable for various biochemical applications
A ferrofluid-based sensor to measure bottom shear stresses under currents and waves
This is an Accepted Manuscript of an article published by Taylor & Francis Group in Journal of Hydraulic Research on 2018, available online at: http://www.tandfonline.com/10.1080/00221686.2017.1397779The measurement of the near-bottom flow characteristics is crucial to correctly understand coastal processes. To overcome some of the limits of present state-of-the-art measuring instruments, we propose a novel approach to measure bottom shear stress under currents and waves based on the exploitation of magneto-rheological fluids, named ferrofluids. In particular, the deformation of a magnetically controlled ferrofluid drop O(0.01 ml) is transformed by a conditioning circuit into an output voltage which is proportional to the bottom shear stress. Calibration curves are presented for both steady-current and regular wave conditions, over fixed and weakly mobile beds, showing that the behaviour of the proposed measuring system can be assumed linear. In the range of the investigated parameters, it is shown that the working range is comprised between 0.08 N m-2 and an upper limit which is a function of the controlling magnetic field and the flow type.Peer ReviewedPostprint (author's final draft
The STAR MAPS-based PiXeL detector
The PiXeL detector (PXL) for the Heavy Flavor Tracker (HFT) of the STAR
experiment at RHIC is the first application of the state-of-the-art thin
Monolithic Active Pixel Sensors (MAPS) technology in a collider environment.
Custom built pixel sensors, their readout electronics and the detector
mechanical structure are described in detail. Selected detector design aspects
and production steps are presented. The detector operations during the three
years of data taking (2014-2016) and the overall performance exceeding the
design specifications are discussed in the conclusive sections of this paper
Thermo-mechanical analysis of flexible and stretchable systems
This paper presents a summary of the modeling and technology developed for flexible and stretchable electronics. The integration of ultra thin dies at package level, with thickness in the range of 20 to 30 ÎĽ m, into flexible and/or stretchable materials are demonstrated as well as the design and reliability test of stretchable metal interconnections at board level are analyzed by both experiments and finite element modeling. These technologies can achieve mechanically bendable and stretchable subsystems. The base substrate used for the fabrication of flexible circuits is a uniform polyimide layer, while silicones materials are preferred for the stretchable circuits. The method developed for chip embedding and interconnections is named Ultra Thin Chip Package (UTCP). Extensions of this technology can be achieved by stacking and embedding thin dies in polyimide, providing large benefits in electrical performance and still allowing some mechanical flexibility. These flexible circuits can be converted into stretchable circuits by replacing the relatively rigid polyimide by a soft and elastic silicone material. We have shown through finite element modeling and experimental validation that an appropriate thermo mechanical design is necessary to achieve mechanically reliable circuits and thermally optimized packages
Exploitation of Transparent Conductive Oxides in the Implementation of a Window-Integrated Wireless Sensor Node
Exploitation of transparent conductive oxides (TCO) to implement an
energy-autonomous sensor node for a wireless sensor network (WSN) is studied
and a practical solution presented. In the practical implementations, flexible
and rigid substrates that is polyimide and glass, are coated with TCO, namely
aluminum doped zinc oxide (AZO). AZO-coated flexible substrates are used to
form thermoelectric generators (TEG) that produce electricity for the sensor
electronics of the node from thermal gradients on a window. As the second
solution to utilize AZO, its conductive properties are exploited to implement
transparent antennas for the sensor node. Antennas for a UHF RFID transponder
and the Bluetooth radio of the node are implemented. A prototype of a flexible
transparent TEG, with the area of 67 cm2 when folded, was measured to produce
power of 1.6 uW with a temperature difference of 43 K. A radiation efficiency
of -9.1 dB was measured for the transparent RFID antenna prototype with the
center frequency of 900 MHz. Radiation efficiencies between -3.8 dB and -0.4
dB, depending on the substrate, were obtained for the 2.45 GHz Bluetooth
antenna.Comment: 10 pages, 14 figures, last author version accepted for publication in
IEEE Sensors Journa
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