COLOR SIGNAL SYSTEMS FOR THE RED-GREEN COLOR BLIND: AN EXPERIMENTAL TEST OF THE THREE-COLOR SIGNAL SYSTEM PROPOSED BY JUDD.

1955 ◽  
Author(s):  
Louise L. Sloan ◽  
Adelaide Habel
1929 ◽  
Vol 41 (2) ◽  
pp. 237 ◽  
Author(s):  
Sibyl Walcutt Terman

2007 ◽  
Vol 24 (3) ◽  
pp. 399-407 ◽  
Author(s):  
MARTIN GEHRES ◽  
CHRISTA NEUMEYER

Large field motion detection in goldfish, measured in the optomotor response, is based on the L-cone type, and is therefore color-blind (Schaerer & Neumeyer, 1996). In experiments using a two-choice training procedure, we investigated now whether the same holds for the detection of a small moving object (size: 8 mm diameter; velocity: 7 cm/s). In initial experiments, we found that goldfish did not discriminate between a moving and a stationary stimulus, obviously not taking attention to the cue “moving.” Therefore, random dot patterns were used in which the stimulus was visible only when moving. Using black and white random dot patterns with variable contrast between 0.2 and 1, we found that the fish could see motion only with high (0.8) contrast. In the decisive experiment, a red-green random dot pattern was used. By keeping the intensity of the red dots constant and reducing the intensity of the green dots, a narrow intensity range was found in which goldfish could no longer discriminate between the moving random dot stimulus in random dot surround and the stationary random dot pattern. The same was the case when a red moving disk was presented in green surround. This is the evidence that object motion is red-green color blind, i.e., color information cannot be used to detect the moving object. Calculations of the cone excitation values revealed that the M-cone type is decisive, as this cone type (and not the L-cone type) is not modulated by that particular red-green pattern in which the moving stimulus was invisible.


Author(s):  
John Hofbauer

There is a growing trend for transit agencies to evolve from wayside and cab-based signal systems to Communication Based Train Control (CBTC). With the complexity of CBTC, a failure of CBTC component could bring a transit system to a standstill. Implementing a secondary signal system can serve to minimize the consequences of a CBTC failure. It is paramount for a transit system to continue to operate, and axle counter technology can be a suitable candidate for use as a secondary signal system. Axle Counter technology has not been widely used in the U.S., but has been used for many years in Europe and the rest of the world. This paper will review and analysis the following: 1. Train Detection Systems; Track circuits vs. axle counters and the basic Principles of Axle Counting; check-in and check-out. 2. Implementing Electromagnetic Compatibility and the EMI standards used in European with previous testing of various axle counter systems, and the frequencies that have been selected, and the proper usage of these frequencies. 3. Testing of radiated emissions using existing guidelines and methods to analyze existing wayside and vehicle Electromagnetic Interferences (EMI), environment conditions, and the limitations of installing axle counters in an existing rail or transit system. 4. Recommendations for improving vehicle and wayside specifications and standards within the U.S. for dealing with installation of axle counter equipment and with failures and EMI emissions between railway devices.


2018 ◽  
Vol 11 (4) ◽  
pp. 365-370
Author(s):  
Ingfar Soontarawirat ◽  
Mallika Imwong ◽  
Charles J. Woodrow ◽  
Chalisa Louicharoen Cheepsunthorn ◽  
Nicholas P.J. Day ◽  
...  

AbstractBackgroundGlucose-6-phosphate dehydrogenase (G6PD) deficiency poses problems for the treatment of Plasmodium vivax malaria, as the 8-aminoquinolines, used to eliminate liver hypnozoites, cause hemolysis in G6PD-deficient individuals.G6PD deficiency is an X-linked disorder that can be linked to other conditions determined by genes located nearby on the Xq28 band of the X chromosome, including red–green color blindness. A Karen population has undergone recent positive selection for G6PD deficiency with extended long-range haplotypes around G6PD.ObjectivesTo determine the association between G6PD deficiency and color blindness in a Karen population that lives in an area endemic for P. vivax and that is already known to display long-range haplotypes around G6PD because of the recent positive selection of the Mahidol G6PD deficiency allele.MethodWe examined the phenotypic association between G6PD deficiency and color blindness.ResultsOf 186 male participants successfully assessed for color blindness using the Ishihara 38 plates test, 10 (5.4%) were red–green color blind, while 1 individual was totally color blind. There was a nonsignificant trend toward negative association (repulsion) between G6PD deficiency and red–green color blindness; 34/35 individuals with the Mahidol variant of G6PD deficiency had normal vision, while 9 of the 10 red–green color blind individuals were G6PD normal. A single individual had both conditions.ConclusionsDespite the long-range haplotype associated with G6PD deficiency in this population, color blindness is not informative in terms of predicting G6PD deficiency in this population. The most likely explanation is that there are multiple genetic causes of red–green color blindness.


2000 ◽  
Vol 26 (S1) ◽  
pp. S209-S213 ◽  
Author(s):  
Lukas R�ttiger ◽  
Helmut Mayser ◽  
Ludwig S�rey ◽  
Lindsay T. Sharpe

2012 ◽  
Vol 178-181 ◽  
pp. 2604-2609
Author(s):  
Yi Zhao ◽  
Zong Tian

This study provided quantitative analyses about the influence of phasing sequences and the impact of intersection spacing. A large number of signal system scenarios were randomly generated to represent the real-world traffic systems. Based on simulation result, it was concluded that Leading and Lagging left turn phasing were more likely to be involved in progression bandwidth solution of signal systems with randomly distributed spacing. And the number of signals has significant impact on bandwidth attainability. Further conclusions were drawn from the fitting curve that it is impossible to obtain any two-way bandwidth solutions when more than 16 signals were involved in the system.


1966 ◽  
Vol 11 (8) ◽  
pp. 374-375
Author(s):  
L. Zusne
Keyword(s):  

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