Effect of Glass Bead Refractive Index on Pavement Marking Retroreflectivity Considering Passenger Vehicle and Airplane Geometries

2020 ◽  
Vol 2674 (10) ◽  
pp. 438-447
Author(s):  
Adam M. Pike ◽  
Songjukta Datta
Keyword(s):  
Refractive Index ◽  
Glass Bead ◽  
Passenger Vehicle ◽  
Standard Measurement ◽  
Bead Size ◽  
Additional Work ◽  
Different Types ◽  
Measurement Geometry ◽  
Pavement Marking

Pavement marking retroreflectivity depends on several factors including but not limited to the type of retroreflective optics, binder, installation quality, marking condition, and measurement type/geometry. Texas A&M Transportation Institute (TTI) evaluated the retroreflectivity of 19 pavement marking panels, prepared with different types of glass bead at standard 30-m and non-standard measurement geometries. The non-standard geometries represented typical commercial airplane configurations. The primary purpose of the research was to evaluate the effects of the glass bead refractive index (RI) (1.5 versus 1.9) and the measurement geometry on pavement marking retroreflectivity. Results showed a decrease in retroreflectivity with an increase in observation and entrance angles for both 1.5 and 1.9 RI. The study showed higher retroreflectivity levels for high RI beads at all the geometries evaluated. The result showed that 1.9 RI beads exhibit an average of 171% (862 mcd/m2/lx) higher retroreflectivity at standard 30-m car geometry as well as 102% (193 mcd/m2/lx) higher retroreflectivity at airplane geometry compared with 1.5 RI beads. The study found that an increase in bead RI had a larger effect on retroreflectivity than did an increase in bead size. The effect of the measurement geometry on the retroreflectivity level of the markings highlights a limitation of using the 30-m car geometry to represent the visibility of markings from a pilot’s perspective. Additional work should be conducted to better assess the visibility of markings from various vehicle platforms and how to best represent the visibility through retroreflectivity measurement.

The History of Cherenkov Detectors

2016 ◽  
pp. 336-345
Keyword(s):  
Refractive Index ◽  
Particle Physics ◽  
Electron Velocity ◽  
Cherenkov Detectors ◽  
Additional Work ◽  
Different Types ◽  
History Of

As early as 1937 Pavel Alexejevitj Cherenkov wrote in one of his papers (Cherenkov, 1937), “...it is possible to pose the problem: for a given electron velocity find a liquid with such a refractive index, that the effect begins to show up. After some additional work this variant of experiments can be used for determination of electron velocities.” Since then many different types of Cherenkov detectors have been successfully developed and used, without which particle physics would probably not have come as far as it has today.

Study on the Glass Beads Refractive Index Testing Technology

2012 ◽  
Vol 487 ◽  
pp. 805-809
Author(s):  
Jun Ma ◽  
Dong Hua Guo
Keyword(s):  
Refractive Index ◽  
Glass Bead ◽  
Glass Beads ◽  
Research Trend ◽  
Future Research ◽  
The Future ◽  
Testing Technology ◽  
At Home

this thesis discusses the main testing technologies at home and abroad relating to the glass bead refractive index, analyses the research emphases relating to the glass bead refractive index testing technology at present and point out the future research trend.

Minimum Safety Distances for Emergency Braking Maneuvers in Car-Following Applications

2020 ◽  
Author(s):  
Devin Schafer ◽  
Pingen Chen
Keyword(s):  
Aerodynamic Force ◽  
Lane Change ◽  
Passenger Vehicle ◽  
Lane Changing ◽  
Car Following ◽  
Emergency Braking ◽  
Safety Distance ◽  
Bicycle Model ◽  
Vehicle Efficiency ◽  
Different Types

Abstract Platooning/car following has been considered as a promising approach for improving vehicle efficiency due to the reduction of aerodynamic force when closely following a pilot vehicle. However, safety is a major concern in the close car platooning/following. This paper investigates the minimum inter-vehicle distances required for a passenger vehicle to safely travel behind a heavy-duty truck with three different types of emergency maneuvers. The three emergency maneuvers considered are braking only, steering only, and braking then steering, where steering refers to a single lane change maneuver. Numerical analysis is conducted for deriving the clearance space in the braking only scenario. In addition, simulations are conducted in MATLAB/Simulink, using a bicycle model for the vehicle dynamics, to examine the minimum safe following distance for the other two scenarios. The simulation results show that, for initial vehicle speeds greater than 8 m/s, a lane change maneuver requires the shortest safety distance. Braking followed by lane changing usually requires the largest minimum safety distance.

Effect of disinfectants and glass bead size on efficacy of glass bead sterlizer

2005 ◽  
Vol 8 (3) ◽  
pp. 23
Author(s):  
Subbiah ◽  
CV Subba Rao ◽  
RG Balaji
Keyword(s):  
Glass Bead ◽  
Bead Size

scholarly journals Content of polymerised triacylglycerols in fat of fried foods

2016 ◽  
Vol 34 (No. 3) ◽  
pp. 211-216
Author(s):  
Mekhanoshina Liliya ◽  
Réblová Zuzana
Keyword(s):  
Refractive Index ◽  
Czech Republic ◽  
French Fries ◽  
The Czech Republic ◽  
Limit Value ◽  
Fat Extraction ◽  
Different Types ◽  
Fried Foods ◽  
Fried Potatoes ◽  
Refractive Index Detection

Polymerised triacylglycerols (TAG) were determined in the fat of 66 industrially produced fried foods (especially frozen pre-fried French fries, potato chips and other fried snacks) and 56 samples of French fries (and other forms of fried potatoes) prepared in restaurants, snack bars, and other catering establishments. All samples were purchased in the Czech Republic, especially in Prague, in the years 2012–2014. Polymerised TAG were determined by HP-SEC with refractive index detection, after the fat extraction with petroleum ether. While in none of the samples of industrially produced fried foods did the content of polymerised TAG in fat exceed the limit value of 12%, in French fries provided by different types of catering establishments this threshold was exceeded in 9 samples (i.e. approximately in 16% of the analysed samples).

Different Types of von Wiilebrand’s Disease (vWd): A Study of 101 Cases

1975 ◽  
Author(s):  
T. Barbui ◽  
F. Baudo ◽  
A. Capitanio ◽  
N. Ciavarella ◽  
P. M. Mannucci ◽  
...  
Keyword(s):  
Factor Viii ◽  
Glass Bead ◽  
Bleeding Time ◽  
Autosomal Dominant ◽  
Type I ◽  
Clinical Form ◽  
Different Types ◽  
Factor Viii Antigen ◽  
Willebrand Factor ◽  
Antihemophilic Factor

The following tests have been carried out in 101 patients with vWd: bleeding time (BT), ristocetin aggregation in PRP (RA), platelet retention to glass bead columns (PR), antihemophilic factor (VIIIAHF). factor-VIII antigen (VIIAGN) and Willebrand factor (VIIIVWF. measured with a washed platelet system), 86 patients had a clinical form of the disease of moderate severity and autosomal dominant pattern of inheritance. In 59 of them VIIIAHF. VIIIAGN and VIIIVWF were concomitantly reduced, PR was usually low and BT moderately prolonged (type I vWd). These patients could be further divided into three subtypes according to the behaviour of RA, which was normal in type la, decreased in type lb and increased in type lc. Typo I vWd is thought to represent an example of decreased synthesis of factor VIII, as suggested by the concomitant decreased of the three factor-VIII related properties. Since RA was found to be either decreased, normal or increased in presence of reduced plasma levels of VTIIVWF. the latter cannot bes solely responsible of the extent of RA in PRP, which may be also related to the variations of a platelet component.27 patients showed very prolonged BT, low PR and absent or markedly rudeced RA: VIIIVWF was much lower than VIIIAHF and VIIIAGN. 15 patients had no family history, a severe clinical form of the disease, unmeasurable levels of VIIIAHF, VIIIAGN and VIIIVWF and markedly abnormal BT, PR and RA. In the majority of their unaffected parents, VIIIVWF and VIIIAGN were much lower than VIIIAHF These patients are similar to the case of recessive vWd described by Veltkamp and Tilbury (N. Engl. J. Med. 289.. 882, 1973).Supported by a grant of the Fondazione Angelo Bianchi Bonomi.

Hemostasis Activating Factor and von Willebrand’s Syndrome

1979 ◽  
Author(s):  
C.M. Kirchmaier ◽  
A. Sayegh ◽  
N. Bender ◽  
St. Lenhard ◽  
M. Wintrich ◽  
...  
Keyword(s):  
Glass Bead ◽  
Subcutaneous Tissue ◽  
Primary Hemostasis ◽  
Tissue Extracts ◽  
Different Types ◽  
Group A ◽  
Rapid Stimulation ◽  
Normal Controls ◽  
Citrate Blood ◽  
Stimulation Of

Small amounts of subcutaneous tissue extracts containing a “hemostasis activating factor”(HaF) induce pseudopode formation and sphering in freshly drawn citrate blood and they markedly enhance platelet retention in glass bead columns. If HaF (50 μl/ml) was added to freshly drawn citrate blood together with a fresh cryoprecipitate (50μ1/ml) from normal PPP, retention was further increased. Cryoprecipitate alone (50μ1/ml) did not induce morphologic platelet changes or enhance platelet retention,I H 15 patients with v.Willebrand syndrome (VWS) spontaneous morphologic platelet changes after blood sampling did not differ from normal controls. But two different types of VWS patients could be distinguished in the retention test: In the first group low retention was increased to norma 1 after the addition of HaF. In a second group a very small or missing increase of platelet retention was found with HaF alone; but retention was “normalised” by adding small amounts of cryoprecipitate together with HaF.VWF may be essential for the rapid stimulation of platelets by HaF in primary hemostasis.

Dynamics of the refractive index induced in germanosilicate optical fibres by different types of UV irradiation

1997 ◽  
Vol 27 (9) ◽  
pp. 785-788 ◽  
Author(s):  
Evgenii M Dianov ◽  
Sergei A Vasil'ev ◽  
O I Medvedkov ◽  
A A Frolov
Keyword(s):  
Refractive Index ◽  
Uv Irradiation ◽  
Optical Fibres ◽  
Different Types

Effects of glass bead size, vortexing speed and duration on Eimeria acervulina oocyst excystation

2014 ◽  
Vol 138 ◽  
pp. 18-24 ◽  
Author(s):  
Jang-Ock Cha ◽  
Abul Fatah Shah Muhammad Talha ◽  
Chae Woong Lim ◽  
Bumseok Kim
Keyword(s):  
Glass Bead ◽  
Eimeria Acervulina ◽  
Bead Size

Comparative Study of Triple-Clad Dispersion-Shifted, Dispersion-Flattened and Dispersion-Compensated Fiber for Broadband Optical Network Application

2016 ◽  
Vol 37 (2) ◽  
Author(s):  
Vikram Palodiya ◽  
Sanjeev Kumar Raghuwanshi
Keyword(s):  
Refractive Index ◽  
Comparative Study ◽  
Optical Fibers ◽  
Propagation Constant ◽  
Optical Network ◽  
Optical Characteristics ◽  
Match Method ◽  
Cylindrical Structure ◽  
Different Types ◽  
Network Application

AbstractIn this paper, comprehensive analyses of triple-clad fibers are presented. The geometry of multiple-clad fibers has been considered as a four-layer cylindrical structure. The geometry consists of a core and three claddings. We have analyzed and compared different types of triple-clad refractive index profiles on the basis of dispersion, mode distribution and propagation constant. To enhance the optical characteristics of these three fibers, we have developed a combined formulation which is applicable for single-clad, double clad and triple-clad optical fibers. In optical fibers, two or more claddings are required for dispersion shifting, dispersion flattening and other specialized applications. Thus, an analysis of design dispersion-shifted, dispersion-flattened and dispersion-compensated fibers is presented. We have used a boundary match method for evaluating propagation wave vectors and guided modes.

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