The paper proposes a method of cutting by generating spur gears using rack cutter with modified geometry. analytical equations the tooth profile rack-gear are deduced, both for involute zone and filleting region, based on remark that is envelope successive positions tool. undercutting radius obtained from system transcendental which requires numerical solving it. Compared to standard profile, d...

This study examined the reliability of a newly developed child and parental questionnaire on specific determinants of cycling to school among 10-12 year olds. Validity of child reported distance, bicycle equipment and basic bicycle skills was also investigated. In total 211 children and 33 parents participated in this study. The reliability of the questionnaires was acceptable with results indi...

Bicycling is a popular recreational activity and a principal mode of transportation for children in the United States, yet about 300 children die and 430,000 are injured annually. Wearing a bicycle helmet is an important countermeasure, since it reduces the risk of serious brain injury by up to 85%. The Centers for Disease Control and Prevention (CDC) have funded state health departments to con...

This paper assesses the completeness of bicycle trail and on-street lane features in OpenStreetMap (OSM). Comparing OSM cycling features with reference data from local planning agencies for selected US Urbanized Areas shows that OSM bicycle trails tend to be more completely mapped than bicycle lanes. Manual evaluation of mapped cycling features in OSM and Google Maps for selected test areas wit...

Enterprise storage clusters increasingly adopt erasure coding to protect stored data against transient and permanent failures. Existing erasure code designs not only introduce extra parity information in a storage-inefficient manner, but also consume substantial cross-rack recovery bandwidth. To relieve both storage and recovery burdens of erasure coding, we adapt our previously proposed STAIR ...

Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation...

Teakwood rack (drawn approximately to scale)Test tubes of equal calibre. . i0^l Pipette for quinine test reagent. (Capacity 0 2|3 that of test tubes.) # rnlitb' Pipette for iodide test reagent. (Capacity slt'' less than J that of the test tubes.) _ u0nt Pipette for iodide mixtures. (Capacity * ?f C-) . gltO'l' Pipette for quinine mixtures. (Capacity 1110 that of B.) Lead plate for stability. Te...