Physical Measurement of Flashing Lights – Now and Then
ثبت نشده
چکیده
This paper begins with a historical review of flashing lights and physical measurement of flashing lights since the time the Blondel-Rey equation was developed. Then the recent work on the physical measurement standards for flashing lights, developed in 1997 at the National Institute of Standards and Technology, is introduced. The paper also discusses the physical requirements and practical aspects of measurements based on the four formulae (Blondel-Rey equation, Form Factor method, Allard method, and Modified Allard method) for effective intensity.
منابع مشابه
Effect of Flashing Brake Lights on Drivers\' Brake Reaction Time and Release Gas Pedal Time
Objective: It is believed that drivers play a crucial role in accidents. Paying attention to brake lights, a driver may find out about danger and react. Rear-end collision accidents refer to the part of the accidents due to driver inattention or slow reaction. The aim of this study was to determine the effect of dynamic flashing brake lights (7 Hz) on drivers' brake reaction time using the driv...
متن کاملاستفاده از شبیه ساز رانندگی بمنظور ارزیابی زمان واکنش راننده به دو نوع چراغ ترمز
Background and aims: Human factors are significant factors causing car accident s . The driver when noticed by brake lights will pay attention to the danger and react appropriately. An appropriate reaction time can prevent car accidents. The aim of this study was to assess driver's reaction time to dynamic flashing and standard brake lights using a driving simulator. Methods: This experimen...
متن کاملCommunication towers, lights, and birds: successful methods of reducing the frequency of avian collisions.
Estimates suggest that each year millions of birds, predominantly Neotropical migrating songbirds, collide with communication towers. To determine the relative collision risks that different nighttime Federal Aviation Administration (FAA) communication tower obstruction lighting systems pose to night-migrating birds, we compared fatalities at towers with different systems: white strobe lights o...
متن کاملThe effect of defocusing the image on the perception of the temporal order of flashing lights.
The temporal interval between flashing lights that is required to perceive nonsimultaneity decreases as the refractive error increases from 0 to +2 diopters. The interval then remains constant with further increases to 3 and 4 diopters. The results are discussed in terms of the relative increase of transient to sustained visual channels and of the increase in apparent movement.
متن کاملA comparison of underwater helicopter-escape lights.
The effectiveness of two types of steady and flashing lights as escape hatch indicators for submerged helicopters was compared. Measurements were taken in moderately and highly turbid water. Response time was faster to the steady lights, and they were more accurately localized. Pairs of steady lights appeared to have some advantage over single lights, but this was not true for flashing lights. ...
متن کامل