منابع مشابه
Preventing occupied wheelchairs from falling down stairs.
The hypothesis was tested that wheelchairs could be prevented from accidentally falling down stairs. A rigid post was attached to the wheelchair frame immediately behind the caster (clearance of 13 mm) such that it would strike the floor just after the casters dropped off an edge. The device was tested by means of a 3-degree ramp at the lower end of which was a level surface that ended with a 1...
متن کاملPreventing death and serious injury from falling trees and branches
Of 128 outdoor education related deaths examined since 1960, 14 have been due to falling trees or branches. This article examines the grounds on which death or serious injury due to falling trees or branches can be regarded as an inherent risk in outdoor education, and the extent to which such incidents can be regarded as preventible. It compares alternative approaches to prevention, and draws ...
متن کاملCategorizing Ideas about Trees: A Tree of Trees
The aim of this study is to explore whether matrices and MP trees used to produce systematic categories of organisms could be useful to produce categories of ideas in history of science. We study the history of the use of trees in systematics to represent the diversity of life from 1766 to 1991. We apply to those ideas a method inspired from coding homologous parts of organisms. We discretize c...
متن کاملPrecise timing when hitting falling balls
People are extremely good at hitting falling balls with a baseball bat. Despite the ball's constant acceleration, they have been reported to time hits with a standard deviation of only about 7 ms. To examine how people achieve such precision, we compared performance when there were no added restrictions, with performance when looking with one eye, when vision was blurred, and when various parts...
متن کاملAsymptotic Cost of Cutting Down Random Free Trees
In this work, we calculate the limit distribution of the total cost incurred by splitting a tree selected at random from the set of all finite free trees. This total cost is considered to be an additive functional induced by a toll equal to the square of the size of tree. The main tools used are the recent results connecting the asymptotics of generating functions with the asymptotics of...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Medicinal & Aromatic Plants
سال: 2012
ISSN: 2167-0412
DOI: 10.4172/2167-0412.1000e111