Adaptive Algorithm for Low-cost Single-frequency Positioning in Urban Environments: Design and Performance Analysis

2018 ◽  
Author(s):  
Ivan Smolyakov ◽  
Richard B. Langley
Keyword(s):  
Performance Analysis ◽  
Adaptive Algorithm ◽  
Low Cost ◽  
Urban Environments ◽  
Single Frequency ◽  
And Performance

Fabrication and performance analysis of a low cost parabolic type solar cooker

2017 ◽  
Author(s):  
Farhana Nasrin Akter ◽  
Muhammed Kamrul Islam ◽  
Nurun Nahar Begum
Keyword(s):  
Performance Analysis ◽  
Low Cost ◽  
Parabolic Type ◽  
And Performance

Design Procedure and Performance Analysis of a Microturbine Combustor Working on Biogas for Power Generation

2019 ◽  
Author(s):  
Bahamin Bazooyar ◽  
Hamidreza Gohari Darabkhani
Keyword(s):  
Performance Analysis ◽  
Fossil Fuels ◽  
Low Cost ◽  
Research Work ◽  
Design Procedure ◽  
Gaseous Emissions ◽  
Cfd Modelling ◽  
Gas Combustion ◽  
Natural Gas Combustion ◽  
And Performance

Abstract Design of the combustor is of high priority in microturbine generators (MTG) due to the small and compact configuration of these type of generators and high range of the shaft revolution (normally over 100k rpm). Design process of the MTG components including the micro combustor and turbomachinery also require accurate description of the combustion phenomena, heat transfer, emission level and performance analysis of the system. Design of combustors for renewable fuels such as biogas has several complications including overcoming the lower heating value of the biogas (normally 1/3 of the natural gas), combustion instabilities and corrosion effects of burning these types of fuels. The main benefit of burning a carbon neutral fuel (e.g., biogas), however will be in reducing the carbon emission by avoiding fossil fuels and achieving the environmental targets (e.g., Paris Agreement). The tubular combustors are in the centre of attention in design and operations of the microturbines due to their low cost and the level of emission. This research work presents the design procedure and CFD modelling of a tubular combustor for a biogas burnt microturbine engine assembly. The biogas is generated from anaerobic digestions of agriculture waste and include a 57% and 43% mixture of methane and CO2 respectively. All the combustor parts are designed with empirical and practical equations and dimensions are optimised by CFD simulations. Operation of the combustor is then analysed in terms of its gaseous emissions. Finally, the operation of the new combustor in a closed heat and power cycle was verified and compared with conventional combustor of the microturbine burning diesel fuel, and as a result all the benefits and considerations for the application of biogas in microturbine assembly are carefully remarked and discussed.

scholarly journals An SVM Based Weight Scheme for Improving Kinematic GNSS Positioning Accuracy with Low-Cost GNSS Receiver in Urban Environments

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7265
Author(s):  
Zhitao Lyu ◽  
Yang Gao
Keyword(s):  
Real Time ◽  
Low Cost ◽  
Urban Environments ◽  
Least Square ◽  
Single Frequency ◽  
Line Of Sight ◽  
Support Vector ◽  
Positioning Accuracy ◽  
Gnss Receiver ◽  
Gnss Positioning

High-precision positioning with low-cost global navigation satellite systems (GNSS) in urban environments remains a significant challenge due to the significant multipath effects, non-line-of-sight (NLOS) errors, as well as poor satellite visibility and geometry. A GNSS system is typically implemented with a least-square (LS) or a Kalman-filter (KF) estimator, and a proper weight scheme is vital for achieving reliable navigation solutions. The traditional weight schemes are based on the signal-in-space ranging errors (SISRE), elevation and C/N0 values, which would be less effective in urban environments since the observation quality cannot be fully manifested by those values. In this paper, we propose a new multi-feature support vector machine (SVM) signal classifier-based weight scheme for GNSS measurements to improve the kinematic GNSS positioning accuracy in urban environments. The proposed new weight scheme is based on the identification of important features in GNSS data in urban environments and intelligent classification of line-of-sight (LOS) and NLOS signals. To validate the performance of the newly proposed weight scheme, we have implemented it into a real-time single-frequency precise point positioning (SFPPP) system. The dynamic vehicle-based tests with a low-cost single-frequency u-blox M8T GNSS receiver demonstrate that the positioning accuracy using the new weight scheme outperforms the traditional C/N0 based weight model by 65.4% and 85.0% in the horizontal and up direction, and most position error spikes at overcrossing and short tunnels can be eliminated by the new weight scheme compared to the traditional method. It also surpasses the built-in satellite-based augmentation systems (SBAS) solutions of the u-blox M8T and is even better than the built-in real-time-kinematic (RTK) solutions of multi-frequency receivers like the u-blox F9P and Trimble BD982.

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