scholarly journals A Comparison of Different Counting Methods for a Holographic Particle Counter: Designs, Validations and Results

Sensors ◽  
2020 ◽  
Vol 20 (10) ◽  
pp. 3006
Author(s):  
Georg Brunnhofer ◽  
Isabella Hinterleitner ◽  
Alexander Bergmann ◽  
Martin Kraft
Keyword(s):  
Three Dimensional ◽  
Nano Particles ◽  
The Novel ◽  
Computational Speed ◽  
Hologram Plane ◽  
Detection And Counting ◽  
Sampling Volume ◽  
Fringe Patterns ◽  
Selection Of

Digital Inline Holography (DIH) is used in many fields of Three-Dimensional (3D) imaging to locate micro or nano-particles in a volume and determine their size, shape or trajectories. A variety of different wavefront reconstruction approaches have been developed for 3D profiling and tracking to study particles’ morphology or visualize flow fields. The novel application of Holographic Particle Counters (HPCs) requires observing particle densities in a given sampling volume which does not strictly necessitate the reconstruction of particles. Such typically spherical objects yield circular intereference patterns—also referred to as fringe patterns—at the hologram plane which can be detected by simpler Two-Dimensional (2D) image processing means. The determination of particle number concentrations (number of particles/unit volume [#/cm 3 ]) may therefore be based on the counting of fringe patterns at the hologram plane. In this work, we explain the nature of fringe patterns and extract the most relevant features provided at the hologram plane. The features aid the identification and selection of suitable pattern recognition techniques and its parameterization. We then present three different techniques which are customized for the detection and counting of fringe patterns and compare them in terms of detection performance and computational speed.

scholarly journals Design and Validation of a Holographic Particle Counter

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4899 ◽  
Author(s):  
Georg Brunnhofer ◽  
Alexander Bergmann ◽  
Andreas Klug ◽  
Martin Kraft
Keyword(s):  
Particle Number ◽  
State Of The Art ◽  
Three Dimensional ◽  
Particle Counter ◽  
Detection And Counting ◽  
Sampling Volume ◽  
Processing Techniques ◽  
The Impact

An in-line holographic particle counter concept is presented and validated where multiple micrometer sized particles are detected in a three dimensional sampling volume, all at once. The proposed PIU is capable of detecting holograms of particles which sizes are in the lower μ m- range. The detection and counting principle is based on common image processing techniques using a customized HT with a result directly relating to the particle number concentration in the recorded sampling volume. The proposed counting unit is mounted ontop of a CNM for comparison with a commercial TSI-3775 CPC. The concept does not only allow for a precise in-situ determination of low particle number concentrations but also enables easy upscaling to higher particle densities (e.g., > 30 . 000 # c c m ) through its linear expandability and option of cascading. The impact of coincidence at higher particle densities is shown and two coincidence correction approaches are presented where, at last, its analogy to the coincidence correction methods used in state-of-the-art CPCs is identified.

Determination of Translation Component of Screw Axis From Double-Exposure Holographic Interferograms

1996 ◽  
Author(s):  
L. A. Sanchez ◽  
A. D. Zurek ◽  
J. A. Griffis
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Rigid Bodies ◽  
Optical Methods ◽  
Screw Axis ◽  
Double Exposure ◽  
Translation Component ◽  
Fringe Patterns ◽  
Relative Motions

Abstract In mechanism design, it is often necessary to accurately measure the relative motions produced by an assembly of rigid bodies connected by joints. A number of analytical tools exist for the theoretical kinematic analysis of the relative motions produced by such an assembly. However, a relatively limited number of corresponding experimental methods for handling such motions exist. Optical methods are especially useful because they do not require that the measurement system touch the assembly being analyzed. A photo-optical method, holographic interferometry, is presented for the experimental determination of finite screw displacements. The purpose of this paper is to show how double-exposure holographic interferograms can be used to provide information about screw axes for general motions of an object in three-dimensional space. This investigation deals with the translation component of a screw axis and categorizes the fringe patterns resulting from in-plane and out-of-plane translations and their combinations. The resulting screw axis for each special displacement case is computed.

scholarly journals Complexation processes in “PbCl2-N2H4CS” aqueous solutions during deposition of lead sulphide films

2021 ◽  
Vol 23 (4) ◽  
pp. 543-547
Author(s):  
Victor N. Semenov ◽  
Vitaly V. Volkov ◽  
Natalia V. Pereslytskikh
Keyword(s):  
Aqueous Solutions ◽  
Coordination Compounds ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Lead Chloride ◽  
Lead Sulphide ◽  
New Approach ◽  
Complex Forms ◽  
Selection Of

In this study, we proposed a new approach to assessing the processes of complexation in aqueous solutions using the example of the interaction of lead chloride with thiourea. The goal of this study was the investigation of processes of complexation in “PbCl2-N2H4CS” aqueous solutions and determination of the regions of dominance of thiourea coordination compounds, which are precursors during the deposition of lead sulphide films.Based on the diagrams and cross section lines of equal fractions constructed in three-dimensional space, the regions of dominance of all complex forms existing in the studied solution were found. Such a graphic image is the most informative, since it allows selection of the concentration ranges of the predominance of certain coordination compounds, especially thiourea complexes, which are precursors during the deposition of lead sulphide films. It was shown that an increase in the concentration of N2H4CS led to an increase in the total fraction of thiourea complexes: for a twofold excess of N2H4CS its fraction was 0.25, for a threefold excess it was 0.35, for a fourfold excess it was 0.5, for a fivefold excess it was 0.7.

Progress in Developing Nerve Agent Sensors Using Combinatorial Techniques

2003 ◽  
Vol 787 ◽  
Author(s):  
John C. DiCesare ◽  
Jennifer Parker ◽  
Starr N. Horne ◽  
Justin Kita ◽  
Raghu Earni ◽  
...  
Keyword(s):  
Molecular Imprinting ◽  
Sol Gel ◽  
Hydrolysis Product ◽  
Three Dimensional ◽  
Nerve Agents ◽  
Nerve Agent ◽  
Silica Sol ◽  
Sol Gel Synthesis ◽  
Selection Of

ABSTRACTDevelopment of a sensor capable of selective detection of specific nerve agents is imperative in today’s atmosphere of terrorism. The sensor needs to be inexpensive, portable, reliable, absent of false positives and available to all military and first responders. By utilizing the techniques of molecular imprinting, combinatorial chemistry, silica sol-gel synthesis and lanthanide luminescence, a sensor for the detection of the hydrolysis product of the nerve agent soman is being developed. There are many parameters that require investigation in order for the sensor to become a reality. These parameters include 1) the selection of a chelate that can bind to the lanthanide and anchor the nerve agent simulant during the formation of the molecularly imprinted polymer, 2) the determination of the environment best suited for this complex formation, 3) the formation, as well as modification of the silica sol-gel for molecular imprinting to take place, and 4) the proper quantity and ratios of monomers used to create the three dimensional imprint. Key to the success of optimizing these parameters is the development of a combinatorial assay that allows for the synthesis and testing of tens of thousands of combinations of parameters. Work on the development of the combinatorial assay has lead to a method of preparing thin film polymers capable of analyzing the presence of nerve agent simulants. Current work is underway to validate the combinatorial assay and to synthesize and evaluate a library of sensor materials selective for nerve agents.

A Novel Device for Standardizing Marker Placement at the Calcaneus

2014 ◽  
Vol 104 (1) ◽  
pp. 43-49 ◽  
Author(s):  
Kevin Deschamps ◽  
Philip Roosen ◽  
Ivan Birch ◽  
Bart Dingenen ◽  
Herman Bruyninckx ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Reference Frames ◽  
Three Dimensional ◽  
Fine Motor ◽  
Intraobserver Variability ◽  
Anatomical Landmarks ◽  
The Novel ◽  
Novel Device ◽  
Repeated Measures Design

Background The determination of anatomical reference frames in the rearfoot during three-dimensional multisegment foot modeling has been hindered by a variety of factors. One of these factors is related to the difficulty in palpating, or the absence of, anatomical landmarks. A novel device (the Calcaneal Marker Device) aimed at standardizing marker placement at the calcaneus was, therefore, developed and evaluated for its reliability. Methods Throughout a random repeated-measures design, the repeatability of calcaneal marker placement was evaluated for two techniques: manual placement and placement using the Calcaneal Marker Device. Translational changes after marker placement and the clinical effect on intersegment angle calculation were quantified. Results Intraobserver variability was greater in therapist 2 (<5.3 mm) compared with therapist 1 (<2.9 mm). Intraobserver variability was also found to be less than 1.6 mm throughout use of the device. Interobserver variability was found to be significantly higher for the position of markers placed manually (5.8 mm), whereas with the Calcaneal Marker Device, the variability remained lower (<1.3 mm). The effect on the computed intersegment angles followed a similar trend, with variability of 0.4° to 4.0° and 1.0° to 8.7° for CMD and manual placement, respectively. Conclusions These findings suggest that variations in marker placement are considerably reduced when the novel Calcaneal Marker Device is used, possibly toward the limits dictated by the fine motor skills of therapists and tissue artifacts.

scholarly journals Distorsion of Isochromatic Fringes in the Process of Stress Measurement in Structural Part by Photoelasticimetry

2018 ◽  
Vol 68 (2) ◽  
pp. 53-60
Author(s):  
Peter Frankovský ◽  
Oskar Ostertag ◽  
Ingrid Delyová
Keyword(s):  
Stress Measurement ◽  
Recording Medium ◽  
Dynamic Effects ◽  
Structural Part ◽  
Isochromatic Fringes ◽  
Different Types ◽  
Color Spectrum ◽  
Fringe Patterns ◽  
Selection Of

AbstractIn the article we show the possibility of distorting the results of the experiment by photoelasticity path, in case the isochromatic fringe patterns are recorded by the camera. The recording of the color spectrum may be distorted by inappropriate selection of the recording medium, which is reflected by different types of aberrations. Transferring a record to a computer allows you to automate the experiment process, thus saving time to work with isochromatic fringes. As an example, we present the experimental determination of the stresses of the rotor with a symmetrical arm. The analysis was performed using software developed by the authors. This software enables full automation of the experiment process. The rotor is investigated by the method of reflection photoelasticity. The experimental solution is realized as a case of periodically repeating dynamic effects, in which a stroboscopic source of white light is needed. The results of the experiment are compared with the numerical solution and their dependence is represented by diagram.

Assessment of offshore sand and gravel bodies for dredging

1998 ◽  
Vol 13 (1) ◽  
pp. 15-31 ◽  
Author(s):  
Ian Selby ◽  
Klaas Ooms
Keyword(s):  
Three Dimensional ◽  
Site Investigation ◽  
Three Dimensional Model ◽  
Reliable Assessment ◽  
Alternative Approach ◽  
Compositional Variability ◽  
Sand And Gravel ◽  
Sand Bodies ◽  
Selection Of

AbstractReliable assessment of offshore sand and gravel resources permits efficient dredging, the maintenance of cargo quality control and the effective mitigation of environmental impacts. Site investigation should be based on the interpretation and correlation of high resolution seismic profiling and CPT/sampling data. A preliminary interpretation of the seismic data reveals the geological setting of the sand bodies and leads to the selection of appropriate sampling methods and the recognition of key sampling positions. Geologically complex sand bodies demand phased data acquisition to delineate geometry, physical properties and compositional variability. The alternative approach, of grid-based sampling using a predetermined sampling density, is costly at best and probably misleading. A three-dimensional model is created from the integration of acquired data and a resource volume calculated. Dredging constraints and overflow losses are applied to the model resulting in the determination of a reserve volume and critical dredging parameters. It is advisable to carry out a wide-ranging testing programme on the recovered samples to ensure compliance with relevant standards or requirements. The potential penalties for superficial site investigation include delay, unpredictable cargo quality and unforeseen environmental problems.

Selection of soluble protein expression constructs: the experimental determination of protein domain boundaries

2010 ◽  
Vol 38 (4) ◽  
pp. 908-913 ◽  
Author(s):  
Michael R. Dyson
Keyword(s):  
Experimental Determination ◽  
Three Dimensional ◽  
Biochemical Properties ◽  
Protein Domain ◽  
Dimensional Structure ◽  
Domain Boundaries ◽  
Clone And Express ◽  
Multiple Domains ◽  
Selection Of

Proteins can contain multiple domains each of which is capable of possessing a separate independent function and three-dimensional structure. It is often useful to clone and express individual protein domains to study their biochemical properties and for structure determination. However, the annotated domain boundaries in databases such as Pfam or SMART are not always accurate. The present review summarizes various strategies for the experimental determination of protein domain boundaries.

scholarly journals Determination of Three-dimensional Structure and Residues of the Novel Tumor Suppressor AIMP3/p18 Required for the Interaction with ATM

2008 ◽  
Vol 283 (20) ◽  
pp. 14032-14040 ◽  
Author(s):  
Kyung-Jin Kim ◽  
Min Chul Park ◽  
So Jung Choi ◽  
Young Sun Oh ◽  
Eung-Chil Choi ◽  
...  
Keyword(s):  
Tumor Suppressor ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
The Novel ◽  
Three Dimensional Structure

scholarly journals Order–disorder transition in monoclinic sulfur: a precise structural study by high-resolution neutron powder diffraction

2006 ◽  
Vol 62 (6) ◽  
pp. 953-959 ◽  
Author(s):  
W. I. F. David ◽  
R. M. Ibberson ◽  
S. F. J. Cox ◽  
P. T. Wood
Keyword(s):  
High Resolution ◽  
Powder Diffraction ◽  
Order Parameter ◽  
Three Dimensional ◽  
Precise Determination ◽  
Neutron Powder Diffraction ◽  
The Novel ◽  
Disorder Transition ◽  
Geometrically Constrained

High-resolution neutron powder diffraction has been used in order to characterize the order–disorder transition in monoclinic cyclo-octasulphur. Rapid data collection and the novel use of geometrically constrained refinements has enabled a direct and precise determination of the order parameter, based on molecular site occupancies, to be made. The transition is critical and continuous; with a transition temperature, Tc = 198.4 (3) K, and a critical exponent, β = 0.28 (3), which is indicative of three-dimensional ordering. Difficulties encountered as a consequence of the low thermal conductivity of the sample are discussed.

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