We study the sawtooth lattice of a coupled spin 1/2 Heisenberg system, a variant of the railroad trestle lattice. The ground state of this system is twofold degenerate with periodic boundary conditions and supports kink antikink excitations, which are distinct in this case, unlike the railroad trestle lattice. The resulting low temperature thermodynamics is compared with the recently discovered...

The benefit provisions and legislative history of the 1951 amendments to the Railroad Retirement Act were summarized in the February Bulletin. In this issue the Chief Actuary of the Social Security Administration discusses the financial and actuarial implications of the amended law, with special emphasis on the provisions coordinating in some measure the railroad program with old-age and surviv...

Railroad equipment manufacturers are surveying a railroad clearance and the environment along rail line to ensure that vehicles can travel safely. Currently, there is need for system accurately measure distance from center of track structures within railroad. Therefore, we have developed 2D-LiDAR create 2D drawings geometry in In this study, propose method detect errors data occur during measur...

Railroad-related accidents are more dangerous than other transportation accidents in terms of severity and death rate etc. Therefore more efforts are necessary for improving safety. In the mean time, Korean national railroad has researched and invested continuously such as intelligent safety equipments and level crossing between railroad and highway for decreasing railroad-related accident and ...

ITE JOURNAL / NOVEMBER 1999 HIGHWAY-RAILROAD GRADE crossings are a relatively unique and sometimes perilous intersection of two transportation modes. The cost of collisions at these intersections is high in both dollars and human lives. The amount and type of sight distance provided at highway-railroad grade crossings can have significant impacts on safety. The proper calculation of these sight...

We study the sawtooth lattice of a coupled spin 1/2 Heisenberg system, a variant of the railroad-trestle lattice. The ground state of this system is twofold degenerate with periodic boundary conditions and supports kink-antikink excitations, which are distinct in this case, unlike the railroad-trestle lattice. The resulting lowtemperature thermodynamics is compared with the recently discovered ...

Diesel exhaust has been suspected to be a lung carcinogen. The assessment of this lung cancer risk has been limited by lack of studies of exposed workers followed for many years. In this study, we assessed lung cancer mortality in 54,973 U.S. railroad workers between 1959 and 1996 (38 years). By 1959, the U.S. railroad industry had largely converted from coal-fired to diesel-powered locomotives...