The Design and Performance of a Sequencing Sediment Trap for Lake Research

Static sediment traps have been successfully used to examine the processes of particle flux and resuspension in large lakes and coastal systems. Although the traps themselves are inexpensive, the deployment and retrieval of them is costly, which restricts both the quantity and frequency of samples. To overcome this, a programmable sequencing sediment trap was designed and tested for use in large lakes and coastal systems. Sediment is collected into a carousel of 23 standard 60 ml (Nalgene™) polyethylene sample bottles. The sequencing design incorporates an electric motor and paddle to rotate the carousel so that one sample bottle at a time is exposed according to a preprogrammed schedule. These traps incorporate a cylindrical design with a 20 cm collection opening and an 8:1 aspect ratio. The micro-controller monitors the operation and records operational parameters allowing corifirmation of the exposure time of each bottle. Several field tests were conducted to verify the precision and uniformity of the sediment collection. Impmvements made over the 10 years of deployment experience and field testing have resulted in a very reliable and low-cost instrument.

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The Outdoor Dust Information Node (ODIN) – development and performance assessment of a low cost ambient dust sensor

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-7511-2015 ◽

2015 ◽

Vol 8 (7) ◽

pp. 7511-7533 ◽

Cited By ~ 19

Author(s):

G. Olivares ◽

S. Edwards

Keyword(s):

Air Quality ◽

Urban Areas ◽

Low Cost ◽

Field Tests ◽

Significant Challenge ◽

Air Quality Measurements ◽

Spatial Coverage ◽

Baseline Response ◽

And Performance ◽

Outdoor Dust

Abstract. The large gradients in air quality expected in urban areas present a significant challenge to standard measurement technologies. Small, low-cost devices have been developing rapidly in recent years and have the potential to improve the spatial coverage of traditional air quality measurements. Here we present the first version of the Outdoor Dust Information Node (ODIN) as well as the results of the first real-world measurements. The lab tests indicate that the Sharp dust sensor used in the ODIN presents a stable baseline response only slightly affected by ambient temperature. The field tests indicate that ODIN data can be used to estimate hourly and daily PM2.5 concentrations after appropriate temperature and baseline corrections are applied. The ODIN seems suitable for campaign deployments complementing more traditional measurements.

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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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Field Testing And Performance Evaluation Of River Water Treatment Plants

10.15405/epsbs.2018.07.02.101 ◽

2018 ◽

Author(s):

HA Mohiyaden

Keyword(s):

Performance Evaluation ◽

Water Treatment ◽

River Water ◽

Field Testing ◽

Water Treatment Plants ◽

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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Driving in the Dust: Challenges and Lessons Learned from Field Testing in Degraded Visual Environments

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/1071181320641462 ◽

2020 ◽

Vol 64 (1) ◽

pp. 1916-1920

Author(s):

Kayla L. Riegner ◽

Kelly S. Steelman

Keyword(s):

Research Program ◽

Field Tests ◽

Field Testing ◽

Driving Performance ◽

Lessons Learned ◽

Current Paper ◽

Ground Vehicle ◽

Significant Safety ◽

Dust Clouds

Degraded visual environments (DVEs) pose significant safety and efficiency problems in military ground vehicle operations. As part of a larger research program, two field tests were conducted to evaluate driving aids while indirect driving in DVEs. The current paper presents the results of one of these field tests, and focuses on the challenges and lessons learned in designing a challenging test course and producing consistent dust clouds for assessing Soldier driving performance and workload in degraded visual environments.

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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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In-Orbit Operational Parameter Calculation and Performance Optimization in KOMPSAT-6 Synthetic Aperture Radar

Remote Sensing ◽

10.3390/rs13122342 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2342

Author(s):

Jin-Bong Sung ◽

Sung-Yong Hong

Keyword(s):

Synthetic Aperture Radar ◽

Performance Optimization ◽

Pulse Repetition Frequency ◽

Optimization Method ◽

Synthetic Aperture ◽

Operational Parameters ◽

Operational Parameter ◽

Design Methodologies ◽

And Performance ◽

Aperture Radar

A new method to design in-orbit synthetic aperture radar operational parameters has been implemented for the Korean Multi-purpose Satellite 6 mission. The implemented method optimizes the pulse repetition frequency when a satellite altitude changes from its nominal one, so it has the advantage that the synthetic aperture radar performances can satisfy the requirements for the in-orbit operation. Other commanding parameters have been designed to conduct trade-off between those parameters. This paper presents the new optimization method to maintain the synthetic aperture radar performances even in the case of an altitude variation. Design methodologies to determine operational parameters, respectively, at nominal altitude and in orbit are presented. In addition, numerical simulation is presented to validate the proposed optimization and the design methodologies.

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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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