This paper describes the mechanical devices, the movements and the associated kinematic models of a novel wheelchair prototype capable of climbing staircases. The key feature of the mechanical design is the use of two decoupled mechanisms in each axle, one used to negotiate steps, and the other to position the axle with respect to the chair to accommodate the overall slope. This decoupling make...

Pricing options on known-dividend-paying stocks has traditionally been solved by assuming that the stock price minus the present value of dividends follows the lognormal diffusion. The same assumption is also popular in tree methods to avoid combinatorial explosion. Unfortunately, this assumption undervalues the option since the volatility of the underlying stock price is underestimated. The bi...

Composite adaptive grid (CAG) methods for solving hyperbolic partial differential equations (PDE's) are discussed in this paper. Composite grids are used at the coarsest level to deal with domains with complicated geometries. Stair step grids developed for composite grids are also used in the ner levels to cover reened regions. New data structures for stair step grids are proposed and implement...

Total knee replacement (TKR) has been the main choice of treatment for advanced knee osteoarthritis (OA). Biomechanics of the knee during stair-ascent has mostly been studied using skin marker-based motion analysis techniques, but no study has reported a complete assessment of the soft tissue artifacts (STA) and their effects on the calculated joint center translation, angles and moments at the...

Stair-climbing is an important skill for promoting independence and activities of daily life and is a key component of rehabilitation therapies for physically disabled children. This thesis describes the design and evaluation of an interactive musical stairs system for children engaged in stairclimbing physical therapies. The achievement of a targeted therapeutic goal, namely, use of reciprocal...

ISSUE ADDRESSED This study investigated the effectiveness of positive and negative-themed message prompts encouraging stair use at the point of choice between an elevator and stairwell in a professional workplace. METHODS A simple time series design using two control periods assessed the efficacy of positive and negative messages on the pedestrian choice between stairs and an elevator in a re...

background: patellofemoral pain (pfp) is a common affliction and complex clinical entity. deficit in neuromotor control of the core may be a remote contributing factor to the development of pfps. comparative evaluation of core and extensor mechanism muscle activation patterns between healthy group and patients involved by patellofemoral pain syndrome(pfps) in a stair stepping task is the aim of...

BACKGROUND Performance tests are important to characterize patient disabilities and functional changes. The Osteoarthritis Research Society International and others recommend the 30-second Chair Stand Test and Stair Climb Test, among others, as core tests that capture two distinct types of disability during activities of daily living. However, these two tests are limited by current protocols of...

Total knee arthroplasty (TKA) is a generally successful surgical procedure to treat end-stage knee osteoarthritis; however, suboptimal outcomes, including difficulty stair climbing, do occur [1]. Clinicians use the stair climbing test (SCT) to track functional status, where a patient ascends and descends a flight of stairs as fast as possible and a faster time suggests better function and incre...