S ince their clinical introduction 10 years ago, hydrophobic acrylic IOLs have gone on to become the most popular foldable IOL category worldwide. According to the annual Leaming surveys of the American Society of Cataract and Refractive Surgery membership, hydrophobic acrylic has been the most preferred IOL material since 1998, and was favoured by 63% of respondents in the 2002 poll. This sust...

We consider sets of coin denominations which permit change to be made using as few coins as possible, on average, and explain why the United States should adopt an 18 piece.

A vehicle body, two bogie frames and two wheelsets for each bogie frame are used to describe the railway vehicle model. The system dynamic is modeled using a 38-DOF system including the longitudinal, lateral, vertical, roll, pitch and yaw displacements. A heuristic nonlinear creep model and the elastic rail are used to simulate the wheel-rail contact. Stable movement and the corresponding limit...

Introduction: Indian Railways at present does not use any automated system for real-time online monitoring of the performance of bogies and wheel-sets. Bogies are checked only during TXR examination for loose or broken parts. Wheel sets are changed when they reach the condemning limit. Problems like skew ness in bogie or asymmetric wheel-wear are attended to during preventive maintenance schedu...

Forestry machines are often travelling on unprepared terrain, which means often rather bumpy ride.4-wheeled machines became 6-wheeled and later on 8 wheeled machines to alleviate the worst obstacles. Nordic forestry people discovered if these wheels were arranged in bogie construction the machine (usually a forwarder that could carry timber) both could better negotiate obstacles and with all wh...

Reduction of the force interaction between vehicle and track is strongly desirable for many reasons. Because conventional methods reduction wheel-rail contact forces, based on tuning suspension parameters or utilising various mechanisms acting wheelsets, bogie-frames car-body, reach their limits, active controlled systems are becoming a promising solution problem. The paper created within proje...

Human errors occurring during railway maintenance activities can significantly reduce the availability of equipment. Identification of potential human errors, their causes and prediction of the associated probabilities are important stages in order to manage such errors. This paper investigates the probability of human error during the maintenance of railway bogies. A case study examines techni...

Forestry machines are often travelling on unprepared terrain, which means often rather bumpy ride.4-wheeled machines became 6-wheeled and later on 8 wheeled machines to alleviate the worst obstacles. Nordic forestry people discovered if these wheels were arranged in bogie construction the machine (usually a forwarder that could carry timber) both could better negotiate obstacles and with all wh...