IMPROVEMENT AND PERFORMANCE EVALUATION OF A SYSTEM FOR MONITORING ROTATIONS AND DISPLACEMENTS OF BRIDGES BASED ON LASER POINTER AND DIGITAL PHOTOGRAMMETRY

Abstract. A system for monitoring rotations and displacements of bridges based on laser pointer and digital photogrammetry is described. The system uses three common laser pointers and image processing. The inclination of the elastic line is measured by analysing the individual frames of an HD video of the laser beam footprint projected onto a flat target. The methodology, able to conjugate a high precision, low cost, and easiness of use, is an evolution of a method developed at University of Calabria, Italy. The use of three laser pointers allows to improve the performance of the previous method, obtaining both displacements and rotations at a generic point of the bridge deck, and deriving the transverse rotation of the deck cross section. The investigated method exploits the laser pointers’ property to provide a steady pointing direction, a long-range and a high-brightness visible imprint. The method and the results of an experimental test are described and discussed.

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Design-Oriented Analysis and Performance Evaluation of a Low-Cost High-Brightness LED Driver Based on Flyback Power Factor Corrector

IEEE Transactions on Industrial Electronics ◽

10.1109/tie.2012.2196905 ◽

2013 ◽

Vol 60 (7) ◽

pp. 2614-2626 ◽

Cited By ~ 51

Author(s):

Diego G. Lamar ◽

Manuel Arias ◽

Alberto Rodriguez ◽

Arturo Fernandez ◽

Marta M. Hernando ◽

...

Keyword(s):

Performance Evaluation ◽

Power Factor ◽

Low Cost ◽

Led Driver ◽

High Brightness ◽

Power Factor Corrector ◽

And Performance

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Characterization Techniques as Supporting Tools for the Interpretation of Biochar Adsorption Efficiency in Water Treatment: A Critical Review

Molecules ◽

10.3390/molecules26165063 ◽

2021 ◽

Vol 26 (16) ◽

pp. 5063

Author(s):

Michele Castiglioni ◽

Luca Rivoira ◽

Irene Ingrando ◽

Massimo Del Bubba ◽

Maria Concetta Bruzzoniti

Keyword(s):

Water Treatment ◽

Water Purification ◽

Low Cost ◽

Efficiency Index ◽

Adsorption Efficiency ◽

The Past ◽

Physicochemical Features ◽

And Performance ◽

The Individual ◽

Significant Attention

Over the past decade, biochar (BC) has received significant attention in many environmental applications, including water purification, since it is available as a low-cost by-product of the energetic valorisation of biomass. Biochar has many intrinsic characteristics, including its porous structure, which is similar to that of activated carbon (AC), which is the most widely used sorbent in water treatment. The physicochemical and performance characteristics of BCs are usually non-homogenously investigated, with several studies only evaluating limited parameters, depending on the individual perspective of the author. Within this review, we have taken an innovative approach to critically survey the methodologies that are generally used to characterize BCs and ACs to propose a comprehensive and ready-to-use database of protocols. Discussion about the parameters of chars that are usually correlated with adsorption performance in water purification is proposed, and we will also consider the physicochemical properties of pollutants (i.e., Kow). Uniquely, an adsorption efficiency index BC/AC is presented and discussed, which is accompanied by an economic perspective. According to our survey, non-homogeneous characterization approaches limit the understanding of the correlations between the pollutants to be removed and the physicochemical features of BCs. Moreover, the investigations of BC as an adsorption medium necessitate dedicated parallel studies to compare BC characteristics and performances with those of ACs.

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Precision and Limits of Detection for Selected Commercially Available, Low-Cost Carbon Dioxide and Methane Gas Sensors

Sensors ◽

10.3390/s19143157 ◽

2019 ◽

Vol 19 (14) ◽

pp. 3157 ◽

Cited By ~ 7

Author(s):

Wesley T. Honeycutt ◽

M. Tyler Ley ◽

Nicholas F. Materer

Keyword(s):

Carbon Dioxide ◽

Low Cost ◽

Detection Limits ◽

Detection Range ◽

Methane Gas ◽

Accuracy And Precision ◽

Sensor Platform ◽

Industrial Monitoring ◽

And Performance ◽

The Individual

The performance of a sensor platform for environmental or industrial monitoring is sensitive to the cost and performance of the individual sensor elements. Thus, the detection limits, accuracy, and precision of commercially available, low-cost carbon dioxide and methane gas concentration sensors were evaluated by precise measurements at known gas concentrations. Sensors were selected based on market availability, cost, power consumption, detection range, and accuracy. A specially constructed gas mixing chamber, coupled to a precision bench-top analyzer, was used to characterize each sensor during a controlled exposure to known gas concentrations. For environmental monitoring, the selected carbon dioxide sensors were characterized around 400 ppm. For methane, the sensor response was first monitored at 0 ppm, close to the typical environmental background. The selected sensors were then evaluated at gas concentrations of several thousand ppm. The determined detection limits accuracy, and precision provides a set of matrices that can be used to evaluate and select sensors for integration into a sensor platform for specific applications.

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

Proceedings of the 2018 International Technical Meeting of The Institute of Navigation ◽

10.33012/2018.15573 ◽

2018 ◽

Author(s):

Ivan Smolyakov ◽

Richard B. Langley

Keyword(s):

Performance Analysis ◽

Adaptive Algorithm ◽

Low Cost ◽

Urban Environments ◽

Single Frequency ◽

And Performance

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Programmable Integrated Photonics

10.1093/oso/9780198844402.001.0001 ◽

2020 ◽

Cited By ~ 4

Author(s):

José Capmany ◽

Daniel Pérez

Keyword(s):

Integrated Circuit ◽

Performance Monitoring ◽

Low Cost ◽

Limiting Factors ◽

External Control ◽

Integrated Photonics ◽

New Paradigm ◽

Photonic Integrated Circuit ◽

And Performance ◽

Application Fields

Programmable Integrated Photonics (PIP) is a new paradigm that aims at designing common integrated optical hardware configurations, which by suitable programming can implement a variety of functionalities that, in turn, can be exploited as basic operations in many application fields. Programmability enables by means of external control signals both chip reconfiguration for multifunction operation as well as chip stabilization against non-ideal operation due to fluctuations in environmental conditions and fabrication errors. Programming also allows activating parts of the chip, which are not essential for the implementation of a given functionality but can be of help in reducing noise levels through the diversion of undesired reflections. After some years where the Application Specific Photonic Integrated Circuit (ASPIC) paradigm has completely dominated the field of integrated optics, there is an increasing interest in PIP justified by the surge of a number of emerging applications that are and will be calling for true flexibility, reconfigurability as well as low-cost, compact and low-power consuming devices. This book aims to provide a comprehensive introduction to this emergent field covering aspects that range from the basic aspects of technologies and building photonic component blocks to the design alternatives and principles of complex programmable photonics circuits, their limiting factors, techniques for characterization and performance monitoring/control and their salient applications both in the classical as well as in the quantum information fields. The book concentrates and focuses mainly on the distinctive features of programmable photonics as compared to more traditional ASPIC approaches.

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The Use of Microcomputer Simulations in Undergraduate Neurophysiology Experiments

Alternatives to Laboratory Animals ◽

10.1177/026119298701400303 ◽

1987 ◽

Vol 14 (3) ◽

pp. 134-140 ◽

Cited By ~ 2

Author(s):

K.A. Clarke

Keyword(s):

Low Cost ◽

Animal Experiments ◽

Theoretical Background ◽

General Purpose ◽

Microcomputer System ◽

Laboratory Equipment ◽

Teaching Objectives ◽

Compound Action Potentials ◽

Experimental Management ◽

And Performance

Practical classes in neurophysiology reinforce and complement the theoretical background in a number of ways, including demonstration of concepts, practice in planning and performance of experiments, and the production and maintenance of viable neural preparations. The balance of teaching objectives will depend upon the particular group of students involved. A technique is described which allows the embedding of real compound action potentials from one of the most basic introductory neurophysiology experiments—frog sciatic nerve, into interactive programs for student use. These retain all the elements of the “real experiment” in terms of appearance, presentation, experimental management and measurement by the student. Laboratory reports by the students show that the experiments are carefully and enthusiastically performed and the material is well absorbed. Three groups of student derive most benefit from their use. First, students whose future careers will not involve animal experiments do not spend time developing dissecting skills they will not use, but more time fulfilling the other teaching objectives. Second, relatively inexperienced students, struggling to produce viable neural material and master complicated laboratory equipment, who are often left with little time or motivation to take accurate readings or ponder upon neurophysiological concepts. Third, students in institutions where neurophysiology is taught with difficulty because of the high cost of equipment and lack of specific expertise, may well have access to a low cost general purpose microcomputer system.

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Experiments with Neural Networks in the Identification and Control of a Magnetic Levitation System Using a Low-Cost Platform

Applied Sciences ◽

10.3390/app11062535 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2535

Author(s):

Bruno E. Silva ◽

Ramiro S. Barbosa

Keyword(s):

Neural Networks ◽

Neural Control ◽

Magnetic Levitation ◽

Low Cost ◽

Training Data ◽

Neural Controllers ◽

Levitation System ◽

Internal Model Controller ◽

Magnetic Levitation System ◽

And Performance

In this article, we designed and implemented neural controllers to control a nonlinear and unstable magnetic levitation system composed of an electromagnet and a magnetic disk. The objective was to evaluate the implementation and performance of neural control algorithms in a low-cost hardware. In a first phase, we designed two classical controllers with the objective to provide the training data for the neural controllers. After, we identified several neural models of the levitation system using Nonlinear AutoRegressive eXogenous (NARX)-type neural networks that were used to emulate the forward dynamics of the system. Finally, we designed and implemented three neural control structures: the inverse controller, the internal model controller, and the model reference controller for the control of the levitation system. The neural controllers were tested on a low-cost Arduino control platform through MATLAB/Simulink. The experimental results proved the good performance of the neural controllers.

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Heat Pump Bridge Analysis Using the Modified Energy Transfer Diagram

Energies ◽

10.3390/en14010137 ◽

2020 ◽

Vol 14 (1) ◽

pp. 137

Author(s):

Florian Schlosser ◽

Heinrich Wiebe ◽

Timothy G. Walmsley ◽

Martin J. Atkins ◽

Michael R. W. Walmsley ◽

...

Keyword(s):

Energy Transfer ◽

Heat Pump ◽

Heat Recovery ◽

Heat Pumps ◽

Coefficient Of Performance ◽

Combined Application ◽

Recovery Potential ◽

Composite Curve ◽

And Performance ◽

The Individual

Heat pumps are the key technology to decarbonise thermal processes by upgrading industrial surplus heat using renewable electricity. Existing insight-based integration methods refer to the idealised Grand Composite Curve requiring the full exploitation of heat recovery potential but leave the question of how to deal with technical or economic limitations unanswered. In this work, a novel Heat Pump Bridge Analysis (HPBA) is introduced for practically targeting technical and economic heat pump potential by applying Coefficient of Performance curves into the Modified Energy Transfer Diagram (METD). Removing cross-Pinch violations and operating heat exchangers at minimum approach temperatures by combined application of Bridge Analysis increases the heat recovery rate and reduce the temperature lift to be pumped at the same time. The insight-based METD allows the individual matching of heat surpluses and deficits of individual streams with the capabilities and performance of different market-available heat pump concepts. For an illustrative example, the presented modifications based on HPBA increase the economically viable share of the technical heat pump potential from 61% to 79%.

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Fabrication and Compressive Behavior of a Micro-Lattice Composite by High Resolution DLP Stereolithography

Polymers ◽

10.3390/polym13050785 ◽

2021 ◽

Vol 13 (5) ◽

pp. 785

Author(s):

Chow Shing Shin ◽

Yu Chia Chang

Keyword(s):

High Resolution ◽

Lattice Structure ◽

Low Cost ◽

Hierarchical Structures ◽

Dip Coating ◽

Unit Cell ◽

Digital Light Processing ◽

Unit Cell Size ◽

Wide Range ◽

And Performance

Lattice structures are superior to stochastic foams in mechanical properties and are finding increasing applications. Their properties can be tailored in a wide range through adjusting the design and dimensions of the unit cell, changing the constituent materials as well as forming into hierarchical structures. In order to achieve more levels of hierarchy, the dimensions of the fundamental lattice have to be small enough. Although lattice size of several microns can be fabricated using the two-photon polymerization technique, sophisticated and costly equipment is required. To balance cost and performance, a low-cost high resolution micro-stereolithographic system has been developed in this work based on a commercial digital light processing (DLP) projector. Unit cell lengths as small as 100 μm have been successfully fabricated. Decreasing the unit cell size from 150 to 100 μm increased the compressive stiffness by 26%. Different pretreatments to facilitate the electroless plating of nickel on the lattice structure have been attempted. A pretreatment of dip coating in a graphene suspension is the most successful and increased the strength and stiffness by 5.3 and 3.6 times, respectively. Even a very light and incomplete nickel plating in the interior has increase the structural stiffness and strength by more than twofold.

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