Preliminary design and characterization of a low-cost and low-power visible light positioning system

2019 ◽  
Vol 58 (26) ◽  
pp. 7181
Author(s):  
Jordan Lui ◽  
Anna Maria Vegni ◽  
Lorenzo Colace ◽  
Alessandro Neri ◽  
Carlo Menon
Keyword(s):  
Low Power ◽  
Visible Light ◽  
Low Cost ◽  
Positioning System ◽  
Preliminary Design

scholarly journals Wind or Hydro Homo-Heteropolar Synchronous Generators: Equivalent Magnetic Circuit and FEM Analysis

2018 ◽  
Vol 210 ◽  
pp. 02008
Author(s):  
Sorin Ioan Deaconu ◽  
Marcel Topor ◽  
Lucian Nicolae Tutelea ◽  
Ilie Nucă ◽  
Marcel Burduniuc
Keyword(s):  
Low Power ◽  
Magnetic Circuit ◽  
Low Cost ◽  
Fem Analysis ◽  
Synchronous Machine ◽  
Preliminary Design ◽  
Synchronous Generators ◽  
3D Fem ◽  
Electric Wind

In an effort to introduce a low cost (PM less), low power electric wind or hydro generators, this paper reports on preliminary design aspects, equivalent magnetic circuit and 3D FEM analysis of a 2.5 KVA, 250-1000 rpm, reactive homo-heteropolar brushless synchronous machine (RHHBSM).

Devising a novel visible light based low-cost ultra-low-power gesture recognition system

2017 ◽  
Author(s):  
Tusher Chakraborty ◽  
Md. Nasim ◽  
Sakib Md. Bin Malek ◽  
Md. Taksir Hasan Majumder ◽  
Md. Samiul Saeef ◽  
...  
Keyword(s):  
Low Power ◽  
Visible Light ◽  
Gesture Recognition ◽  
Low Cost ◽  
Recognition System ◽  
Ultra Low Power

scholarly journals Ultra-Low-Power, High-Accuracy 434 MHz Indoor Positioning System for Smart Homes Leveraging Machine Learning Models

Entropy ◽  
2021 ◽  
Vol 23 (11) ◽  
pp. 1401
Author(s):  
Haq Nawaz ◽  
Ahsen Tahir ◽  
Nauman Ahmed ◽  
Ubaid U. Fayyaz ◽  
Tayyeb Mahmood ◽  
...  
Keyword(s):  
Low Power ◽  
Indoor Localization ◽  
Low Cost ◽  
Smart Homes ◽  
Indoor Positioning ◽  
High Accuracy ◽  
Positioning System ◽  
Telemetry Data ◽  
Ultra Low Power ◽  
Indoor Positioning System

Global navigation satellite systems have been used for reliable location-based services in outdoor environments. However, satellite-based systems are not suitable for indoor positioning due to low signal power inside buildings and low accuracy of 5 m. Future smart homes demand low-cost, high-accuracy and low-power indoor positioning systems that can provide accuracy of less than 5 m and enable battery operation for mobility and long-term use. We propose and implement an intelligent, highly accurate and low-power indoor positioning system for smart homes leveraging Gaussian Process Regression (GPR) model using information-theoretic gain based on reduction in differential entropy. The system is based on Time Difference of Arrival (TDOA) and uses ultra-low-power radio transceivers working at 434 MHz. The system has been deployed and tested using indoor measurements for two-dimensional (2D) positioning. In addition, the proposed system provides dual functionality with the same wireless links used for receiving telemetry data, with configurable data rates of up to 600 Kbauds. The implemented system integrates the time difference pulses obtained from the differential circuitry to determine the radio frequency (RF) transmitter node positions. The implemented system provides a high positioning accuracy of 0.68 m and 1.08 m for outdoor and indoor localization, respectively, when using GPR machine learning models, and provides telemetry data reception of 250 Kbauds. The system enables low-power battery operation with consumption of <200 mW power with ultra-low-power CC1101 radio transceivers and additional circuits with a differential amplifier. The proposed system provides low-cost, low-power and high-accuracy indoor localization and is an essential element of public well-being in future smart homes.

Synthesis and Characterization of Photocatalytic TiO2-ZnFe2O4 Nanoparticles

2005 ◽  
Vol 876 ◽  
Author(s):  
Sesha S. Srinivasan ◽  
Jeremy Wade ◽  
Elias K. Stefanakos
Keyword(s):  
Visible Light ◽  
Low Cost ◽  
Anatase Phase ◽  
Solar Spectrum ◽  
Rutile Phase ◽  
Oxidation Potential ◽  
Narrow Bandgap ◽  
Visible Wavelengths ◽  
Indoor Lighting

AbstractThe wide bandgap semiconductor TiO2 has become the dominant UV-activated photocatalyst in the field of air and water detoxification because of its high stability, low cost, high oxidation potential and chemically favorable properties. The demand for visible-light activated photocatalytic systems is increasing rapidly; however, currently, the efficiency and availability of photocatalysts that can be activated effectively by the solar spectrum and particularly indoor lighting is severely limited. In this paper, a new coprecipitation/hydrolysis synthesis route is used to create a TiO2-ZnFe2O4 nanocomposite that is directed towards extending the photoresponse of TiO2 from UV to visible wavelengths (>400nm). The effect of TiO2's accelerated anatase-rutile phase transformation due to the presence of the coupled ZnFe2O4 narrow bandgap semiconductor is evaluated. The transformation's dependence on pH, calcination temperature, particle size, and ZnFe2O4 concentration has been analyzed using XRD, SEM, and UV-Visible spectrometry. The requirements for retaining the highly photoactive anatase phase present in a ZnFe2O4 nanocomposite are outlined. The visible-light activated photocatalytic activity of the TiO2-ZnFe2O4 nanocomposites have been compared to an Aldrich TiO2 reference catalyst, using a solar-simulated photoreactor for the degradation of phenol.

scholarly journals A Tilt Visible Light Positioning System Based on Double LEDs and Angle Sensors

Electronics ◽  
2021 ◽  
Vol 10 (16) ◽  
pp. 1923
Author(s):  
Futong An ◽  
Haixin Xu ◽  
Shangsheng Wen ◽  
Hongzhan Song ◽  
Zhijian Chen ◽  
...  
Keyword(s):  
Visible Light ◽  
Low Cost ◽  
Location Based Services ◽  
Vertical Position ◽  
Positioning System ◽  
Geometric Information ◽  
Imaging Characteristics ◽  
Mobile Receiver ◽  
Relationship Of ◽  
The Relationship

Visible light positioning (VLP) has been studied widely due to its high accuracy and low cost in the field of location-based services (LBS). However, many existing VLP systems have the requirements that the receiver should be placed horizontally and more than three LED lamps should be used, which are difficult to meet in practical scenarios. Therefore, it is necessary to develop a novel VLP algorithm for tilted conditions. An effective and simple VLP system while the receiver is tilted based on double-LED lamps is proposed in this paper. The vertical position can be determined by combining the information from angle sensors with geometric information. Through analyzing the imaging characteristics of the tilted state, we can utilize the relationship of similarity to calculate the location of the mobile receiver. Experimental results show that the positioning accuracy of our proposed algorithm can reach 5.48 cm.

scholarly journals Characterization of electric faults in photovoltaic array systems

DYNA ◽  
2019 ◽  
Vol 86 (211) ◽  
pp. 54-63
Author(s):  
Andres Eduardo Nieto Vallejo ◽  
Fredy Ruiz ◽  
Diego Patiño
Keyword(s):  
Solar Radiation ◽  
Low Power ◽  
Low Cost ◽  
Open Circuit ◽  
Equivalent Circuits ◽  
Pv Systems ◽  
Photovoltaic Array

Electric faults in photovoltaic (PV) systems cause negative economic and safety impacts, reducing their performance and causing unwanted electric connections that can be dangerous for the user. Line to line, ground and open circuit faults, are three of the main faults that happen in a photovoltaic array system. This work proposes a characterization of the equivalent circuits and the voltage-power (VP) curves at the output of multiple PV arrays under different topological configurations and fault conditions to evaluate the effects of these three main faults on the performance of a photovoltaic array system, taking into account the temperature and solar radiation influence. This work presents a validation of the characterization by measuring the output VP curves of a low-power photovoltaic array system under real outdoors conditions. This method can be useful in future works to develop low cost systems capable of detecting and classifying electric faults in photovoltaic array systems.

Sign in / Sign up

Export Citation Format

Share Document