572 resultados para Sun: flares


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Recognized around the world as a powerful beacon for freedom, hope, and opportunity, the Statue of Liberty's light is not just metaphorical: her dramatic illumination is a perfect example of American ingenuity and engineering. Since the statue's installation in New York Harbor in 1886, lighting engineers and designers had struggled to illuminate the 150-foot copper-clad monument in a manner becoming an American icon. It took the thoughtful and creative approach of Howard Brandston-a legend in his own right-to solve this lighting challenge. In 1984, the designer was asked to give the statue a much-needed lighting makeover in preparation for its centennial. In order to avoid the shortcomings of previous attempts, he studied the monument from every angle and in all lighting conditions, discovering that it looked best in the light of dawn. Brandston determined that he would need 'one lamp to mimic the morning sun and one lamp to mimic the morning sky.' Learning that no existing lamps could simulate these conditions, Brandston partnered with General Electric to develop two new metal halide products. With only a short time for R&D, a team of engineers at GE's Nela Park laboratories assembled a 'top secret' testing room dedicated to the Statue of Liberty project. After nearly two years of work to perfect the new lamps, the 'dawn's early light' effect was finally achieved just days before the centennial celebrations were to take place in 1986. 'It was truly a labor of love,' he recalls.

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Derailments due to lateral collisions between heavy road vehicles and passenger trains at level crossings (LCs) are serious safety issues. A variety of countermeasures in terms of traffic laws, communication technology and warning devices are used for minimising LC accidents; however, innovative civil infrastructure solution is rare. This paper presents a study of the efficacy of guard rail system (GRS) to minimise the derailment potential of trains laterally collided by heavy road vehicles at LCs. For this purpose, a three-dimensional dynamic model of a passenger train running on a ballasted track fitted with guard rail subject to lateral impact caused by a road truck is formulated. This model is capable of predicting the lateral collision-induced derailments with and without GRS. Based on dynamic simulations, derailment prevention mechanism of the GRS is illustrated. Sensitivities of key parameters of the GRS, such as the flange way width, the installation height and contact friction, to the efficacy of GRS are reported. It is shown that guard rails can enhance derailment safety against lateral impacts at LCs.