In this paper, we formulate the array robustness theorems (ARTs) for efficient computation and communication on faulty arrays. No hardware redundancy is required and no assumption is made about the availability of a complete submesh or subtorus. Based on ARTs, a very wide variety of problems, including sorting, FFT, total exchange, permutation, and some matrix operations, can be solved with a s...

A rail transit network usually represents the core of a city’s public transportation system. The overall topological structures and functional features of a public transportation network, therefore, must be fully understood to assist the safety management of rail transit and planning for sustainable development. Based on the complex network theory, this study took the Beijing Subway system (BSS...

Preventing broken-rail-caused derailments is a high priority for the rail industry and government. The current practice is to periodically inspect rails using non-destructive technologies such as ultrasonic rail inspection. Determining the optimal inspection frequency is a critical decision in railway infrastructure management. The objective of this paper is to develop an analytical framework t...

Rail surface defects such as the abrasion, scratch and peeling often cause damages to the train wheels and rail bearings. An efficient and accurate detection of rail defects is of vital importance for the safety of railway transportation. In the past few decades, automatic rail defect detection has been studied; however, most developed methods use optic-imaging techniques to collect the rail su...

The type and magnitude of loads passing through the track superstructure have a great impact on both the design and the performance of concrete sleepers and fastening systems. To date, the majority of North American research focusing on quantifying rail infrastructure loading conditions has been conducted on heavy-haul freight railroads. However, the results and recommendations from these studi...

Impacts of livestock grazing in arid and semiarid environments are often concentrated in and around wetlands where animals congregate for water, cooler temperatures, and green forage. We assessed the impacts of winter-spring (November-May) cattle grazing on marsh vegetation cover and occupancy of a highly secretive marsh bird that relies on dense vegetation cover, the California Black Rail (Lat...

AIMS To determine the ownership and use of various assistive devices by older people living at home. METHOD A random sample of 1405 elderly people aged 65 years and over, in three health authorities, were asked about ownership and use of a number of disability aids, spectacles and hearing aids. RESULTS 74% of respondents owned one or more aid, 97% had spectacles and 16% a hearing aid. The m...