High-Index Glass Ball Retroreflectors for Measuring Lateral Positions

Andrea Egidi; Alessandro Balsamo; Marco Pisani

doi:10.3390/s19051082

High-Index Glass Ball Retroreflectors for Measuring Lateral Positions

Sensors ◽

10.3390/s19051082 ◽

2019 ◽

Vol 19 (5) ◽

pp. 1082 ◽

Cited By ~ 1

Author(s):

Andrea Egidi ◽

Alessandro Balsamo ◽

Marco Pisani

Keyword(s):

Lateral Position ◽

Mie Scattering ◽

Representative Point ◽

Glass Ball ◽

Fitness For Purpose ◽

Dielectric Spheres ◽

Noisy Conditions ◽

Traditional Approaches ◽

Luminous Signals ◽

Coherent Source

This paper is concerned with backscattered luminous signals, coming from a particular class of dielectric spheres illuminated by a coherent source. The purpose is to measure the lateral position of the sphere serving as an optical target, to achieve an overall contactless sensor of lateral position in space. Traditional approaches and theories such as ray-tracing and Mie scattering—as implemented in dedicated software—are applied to investigate their fitness for purpose in this application. No previous literature was found dealing with this specific case. Unfortunately, our observations did not match the theories’ predictions to an acceptable degree, and these approaches proved to be unsatisfactory. The rest of the paper focusses then on the development and comparison of suitable algorithms to compute the image coordinates of a representative point, which was in fact the true motivation of this work. Two original algorithms are proposed and discussed. Their robustness and repeatability are benchmarked under noisy conditions and at different distances from the target, with simulated as well as real images. Both resulted capable of sub-pixel accuracy.

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The role of the angular momentum of light in Mie scattering. Excitation of dielectric spheres with Laguerre–Gaussian modes

Journal of Quantitative Spectroscopy and Radiative Transfer ◽

10.1016/j.jqsrt.2012.10.010 ◽

2013 ◽

Vol 126 ◽

pp. 50-55 ◽

Cited By ~ 22

Author(s):

Xavier Zambrana-Puyalto ◽

Gabriel Molina-Terriza

Keyword(s):

Angular Momentum ◽

Mie Scattering ◽

Dielectric Spheres

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Characteristics of downed wood across headwater riparian ecotones: integrating the stream with the riparian area

Canadian Journal of Forest Research ◽

10.1139/x10-106 ◽

2010 ◽

Vol 40 (8) ◽

pp. 1604-1614 ◽

Cited By ~ 1

Author(s):

Kathryn L. Holmes ◽

P. Charles Goebel ◽

Arthur E.L. Morris

Keyword(s):

Riparian Forest ◽

Structural Characteristics ◽

Transitional Zone ◽

Lateral Position ◽

Riparian Area ◽

Holistic Management ◽

Decay Class ◽

Structural Relationships ◽

Downed Wood ◽

Traditional Approaches

Although downed wood is a significant structural component of riparian ecotones, most studies of downed wood dynamics are conducted only within the stream bankfull channel or on the riparian forest floor. We examined downed wood structural characteristics (e.g., length, volume, and decay class) across the entire riparian ecotone of seven headwater streams in mature deciduous forests of northeastern Ohio to understand the structural relationships between downed wood and riparian ecotones. Sampling was stratified by hydrogeomorphic zones that were defined by lateral position within the riparian ecotone and correspond to differing fluvial geomorphology. Most downed wood pieces sampled were small (<1 m) and with a high decay class. Downed wood pieces within the baseflow zone (within the wetted channel) were smaller and more abundant than those within the transitional zone (within the bankfull channel excluding the wetted channel). Surface contact was inversely related to aquatic influence across the riparian ecotone, with downed wood in Zone 3 (riparian area beyond the bankfull channel) having significantly higher contact than wood within the other zones. The ecotonal approach and the incorporation of hydrogeomorphic influences is an alternative approach that moves beyond traditional approaches to more holistic management of riparian forests.

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Microsurgical Endoscope-Assisted Gravity-Aided Transfalcine Approach for Contralateral Metastatic Deep Medial Cortical Tumors

Operative Neurosurgery ◽

10.1093/ons/opx067 ◽

2017 ◽

Vol 13 (6) ◽

pp. 724-731 ◽

Cited By ~ 8

Author(s):

Garni Barkhoudarian ◽

Daniel Farahmand ◽

Robert G Louis ◽

Erol Oksuz ◽

Danjuma Sale ◽

...

Keyword(s):

Tumor Resection ◽

Metastatic Tumor ◽

Lateral Position ◽

Metastatic Tumors ◽

Total Resection ◽

Tumor Visualization ◽

Surgical Ergonomics ◽

Endoscopic Assistance ◽

Brain Retraction ◽

Traditional Approaches

Abstract BACKGROUND Traditional approaches to deep medial cortical tumors utilize transcortical or ipislateral interhemispheric approaches, which can result in cortical damage or retraction injury. To reduce these risks, the microscopic transfalcine approach has been previously described. OBJECTIVE To describe this approach performed with endoscopic assistance for metastatic tumor resection, demonstrating appropriate and safe tumor resection without injury to the contralateral hemisphere. METHODS Eleven consecutive patients harboring medial, deep metastatic tumors are reported. Tumor resection was performed with endoscopic assistance with 2 surgeons. Clinical outcomes are recorded. RESULTS All 11 patients underwent safe tumor resection. Gross total resection was achieved in 73% of patients. The application of the angled endoscope allowed for further tumor resection in 91% of patients. There were no complications in these patients. The contralateral brain did not demonstrate clinical or radiographic injury as well. CONCLUSION This series suggests that the endoscopic transfalcine approach in the lateral position can be a safe and effective approach for resecting medial interhemispheric metastatic tumors. It allows excellent tumor visualization, eliminates the need for brain retraction, minimizes parenchymal transgression, and improves surgical ergonomics. A familiarity of endoscopy and neuroanesthesia support is helpful when utilizing this approach.

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Macrostructure and microphysics of Saturn's E-ring

International Astronomical Union Colloquium ◽

10.1017/s0252921100101691 ◽

1984 ◽

Vol 75 ◽

pp. 607-613 ◽

Cited By ~ 2

Author(s):

Kevin D. Pang ◽

Charles C. Voge ◽

Jack W. Rhoads

Keyword(s):

Size Distribution ◽

Spherical Shape ◽

Mie Scattering ◽

Narrow Size Distribution ◽

Electrostatic Levitation ◽

Volcanic Origin ◽

Micron Diameter

Abstract.All observed optical and infrared properties of Saturn's E-ring can be explained in terms of Mie scattering by a narrow size distribution of ice spheres of 2 - 2.5 micron diameter. The spherical shape of the ring particles and their narrow size distribution imply a molten (possibly volcanic) origin on Enceladus. The E-ring consists of many layers, possibly stratified by electrostatic levitation.

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A simple way for producing holographic filters suitable for image improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108271 ◽

1978 ◽

Vol 36 (1) ◽

pp. 226-227

Author(s):

K.-H. Herrmann ◽

E. Reuber ◽

P. Schiske

Keyword(s):

Transfer Functions ◽

Diffraction Order ◽

Lateral Position ◽

Simple Method ◽

Spatial Frequencies ◽

Resolution Electron ◽

Wiener Filters ◽

Image Improvement ◽

Optical Reconstruction ◽

Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

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Pragmatic versus Morphological/Syntactic Criteria for Language Referrals

Language Speech and Hearing Services in Schools ◽

10.1044/0161-1461.1102.85 ◽

1980 ◽

Vol 11 (2) ◽

pp. 85-94 ◽

Cited By ~ 25

Author(s):

Jack Damico ◽

John W. Oller

Keyword(s):

Grade Level ◽

The State ◽

Verb Agreement ◽

Remedial Programs ◽

Service Training ◽

Traditional Approaches ◽

Communicative Effectiveness

Two methods of identifying language disordered children are examined. Traditional approaches require attention to relatively superficial morphological and surface syntactic criteria, such as, noun-verb agreement, tense marking, pluralization. More recently, however, language testers and others have turned to pragmatic criteria focussing on deeper aspects of meaning and communicative effectiveness, such as, general fluency, topic maintenance, specificity of referring terms. In this study, 54 regular K-5 teachers in two Albuquerque schools serving 1212 children were assigned on a roughly matched basis to one of two groups. Group S received in-service training using traditional surface criteria for referrals, while Group P received similar in-service training with pragmatic criteria. All referrals from both groups were reevaluated by a panel of judges following the state determined procedures for assignment to remedial programs. Teachers who were taught to use pragmatic criteria in identifying language disordered children identified significantly more children and were more often correct in their identification than teachers taught to use syntactic criteria. Both groups identified significantly fewer children as the grade level increased.

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Parasocial Interaction as More Than Friendship

Journal of Media Psychology Theories Methods and Applications ◽

10.1027/1864-1105/a000044 ◽

2011 ◽

Vol 23 (3) ◽

pp. 122-132 ◽

Cited By ~ 22

Author(s):

Jayson L. Dibble ◽

Sarah F. Rosaen

Keyword(s):

Parasocial Interaction ◽

Future Research ◽

Two Measures ◽

Traditional Approaches

This study supports the refinement of the concept of parasocial interaction (PSI) to apply to mediated personae that viewers might dislike. By contrast, traditional approaches have treated PSI as a sort of friendship with the mediated persona. Participants (N = 249) were randomly assigned to self-select a liked or disliked television persona. Various viewer reactions to that character were measured using two different measures of PSI. The data revealed that participants did experience PSI with disliked characters as well as liked characters, and that the two measures of PSI did not appear to assess the same construct. Implications for future research are discussed.

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