A New High-Efficiency Procedure for Aggregate Gradation Determination of the Railway Ballast by Means Image Recognition Method

Abstract The mechanical characteristics of the railway superstructure are related to the properties of the ballast, and especially to the particle size distribution of its grains. Under the constant stress-strain of carriages, the ballast can deteriorate over time, and consequently it should properly be monitored for safety reasons. The equipment which currently monitors the railway superstructure (like the Italian diagnostic train Archimede) do not make any “quantitative” evaluation of the ballast. The aim of this paper is therefore to propose a new methodology for extracting railway ballast particle size distribution by means of the image processing technique. The procedure has been tested on a regularly operating Italian railway line and the results have been compared with those obtained from laboratory experiments, thus assessing how effective is the methodology which could potentially be implemented also in diagnostic trains in the near future.

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Foster®: A High-Efficiency Combination Metered Dose Inhaler with Consistent Particle Size Distribution at Alternative Flow Rates

Combination Products in Therapy ◽

10.1007/s13556-013-0006-6 ◽

2014 ◽

Vol 4 (1-2) ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Roberta De Maria ◽

Ingrid Zagnoni ◽

Alessandro Bodria ◽

Sauro Bonelli ◽

Massimiliano Dagli Alberi ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

High Efficiency ◽

Dose Inhaler ◽

Metered Dose Inhaler ◽

Flow Rates ◽

Metered Dose

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HEPA Filter Performance Under Adverse Conditions

11th International Conference on Environmental Remediation and Radioactive Waste Management, Parts A and B ◽

10.1115/icem2007-7074 ◽

2007 ◽

Author(s):

Michael Parsons ◽

Kristina Hogancamp ◽

Steven Alderman ◽

Charles Waggoner

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

High Efficiency ◽

Department Of Energy ◽

Emission Rates ◽

Filter Function ◽

Filter Performance ◽

The Media ◽

Effect Of Particle Size

This study involved challenging nuclear grade high-efficiency particulate air (HEPA) filters under a variety of conditions that can arise in Department of Energy (DOE) applications such as: low or high RH, controlled and uncontrolled challenge, and filters with physically damaged media or seals (i.e., leaks). Reported findings correlate filter function as measured by traditional differential pressure techniques in comparison with simultaneous instrumental determination of up and down stream PM concentrations. Additionally, emission rates and failure signatures will be discussed for filters that have either failed or exceeded their usable lifetime. Significant findings from this effort include the use of thermocouples up and down stream of the filter housing to detect the presence of moisture. Also demonstrated in the moisture challenge series of tests is the effect of repeated wetting of the filter. This produces a phenomenon referred to as transient failure before the tensile strength of the media weakens to the point of physical failure. An evaluation of the effect of particle size distribution of the challenge aerosol on loading capacity of filters is also included. Results for soot and two size distributions of KCl are reported. Loading capacities for filters ranged from approximately 70 g of soot to nearly 900 g for the larger particle size distribution of KCl.

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New Proposal for Size and Size-Distribution Evaluation of Nanoparticles Synthesized via Ultrasonic Spray Pyrolysis Using Search Algorithm Based on Image-Processing Technique

Materials ◽

10.3390/ma13010038 ◽

2019 ◽

Vol 13 (1) ◽

pp. 38 ◽

Cited By ~ 3

Author(s):

Elif Emil Kaya ◽

Ozan Kaya ◽

Gözde Alkan ◽

Sebahattin Gürmen ◽

Srecko Stopic ◽

...

Keyword(s):

Image Processing ◽

Particle Size ◽

Spray Pyrolysis ◽

Size Distribution ◽

Search Algorithm ◽

Ultrasonic Spray Pyrolysis ◽

Processing Technique ◽

Image Processing Technique ◽

Sem Micrographs ◽

Ultrasonic Spray

Nanoparticle properties are correlated to their size, size distribution, and shape; it is essential to accurately measure these features in the field of nanoscience. In this study, silver nanoparticles (AgNPs) were synthesized with the ultrasonic-spray-pyrolysis (USP) method from a water solution of silver nitrate. The synthesized AgNPs were characterized by Dynamic Light Scattering (DLS) analysis and Scanning Electron Microscopy (SEM) to reveal their size and size distribution. A search algorithm based on an image-processing technique to obtain particle size and particle-size distribution from SEM micrographs is proposed. In order to obtain more quantitative information and data with respect to the morphology of particles synthesized under different process parameters, SEM micrographs with a nonhomogeneous background contrast were examined via image-processing techniques in MATLAB. Due to the inhomogeneous contrast of SEM micrographs, defining an overall threshold value was insufficient in the detection of whole nanoparticles. Thus, subimages were directly created according to the maximum and minimum particle size specified by the user to determine local threshold values. The obtained results were automatically combined to represent both particle dimension and location in the SEM micrographs. We confirmed that the results of our DLS analysis, theoretical calculation, and image-processing technique were correlated with our expected results.

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High efficiency, narrow particle size distribution, sub-2 μm based macrocyclic glycopeptide chiral stationary phases in HPLC and SFC

Analytica Chimica Acta ◽

10.1016/j.aca.2015.09.048 ◽

2015 ◽

Vol 898 ◽

pp. 128-137 ◽

Cited By ~ 57

Author(s):

Chandan L. Barhate ◽

M. Farooq Wahab ◽

Zachary S. Breitbach ◽

David S. Bell ◽

Daniel W. Armstrong

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

High Efficiency ◽

Stationary Phases ◽

Chiral Stationary Phases ◽

Narrow Particle Size Distribution ◽

Macrocyclic Glycopeptide

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Effect of particle size distribution and subgrade condition on degradation of railway ballast under impact loads

Granular Matter ◽

10.1007/s10035-017-0747-0 ◽

2017 ◽

Vol 19 (3) ◽

Cited By ~ 16

Author(s):

Mehdi Koohmishi ◽

Massoud Palassi

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Impact Loads ◽

Railway Ballast ◽

Effect Of Particle Size

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Effect of Aggregate Gradation on the Stiffness of Asphalt Mixtures

International Journal on Pavement Engineering & Asphalt Technology ◽

10.1515/ijpeat-2015-0008 ◽

2015 ◽

Vol 16 (2) ◽

pp. 39-49 ◽

Cited By ~ 6

Author(s):

Hasan Al-Mosawe ◽

Nick Thom ◽

Gordon Airey ◽

Amjad Al-Bayati

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Asphalt Concrete ◽

Asphalt Mixture ◽

Asphalt Mixtures ◽

Volumetric Properties ◽

Aggregate Gradation ◽

Effect Of Particle Size ◽

Indirect Tensile

Abstract Aggregate gradation plays an important role in the behaviour of asphalt mixtures. Packing of aggregate is a very important factor that will be affected by changing the aggregate gradation. Many researchers have investigated different ways of describing packing both theoretically and practically. Bailey ratios have recently been used to understand the volumetric properties of mixtures. In this paper, the Bailey ratios have been used, and two further ratios have also been introduced to allow the asphalt mixture gradation to be fully understood. Thirteen different aggregate gradations have been chosen within the 14 mm asphalt concrete specification to investigate the effect of particle size distribution on the stiffness of the mixture. It was found that variation in aggregate gradation has a significant effect on asphalt stiffness, even within specification limits, and a reasonable correlation between the set of ratios investigated and the Indirect Tensile Stiffness.

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