372 research outputs found
The use of laser scanning as a method for measuring stairways following an accident
Copyright: 2015 Survey Review Ltd.MORE OpenChoice: Open Access ArticleStairs present significant potential for harm to their users. A fall on stairs, particularly in descent,
often leads to serious injury or even death. The authors have been involved in the investigation of
many workplace stair accidents. Proper forensic investigation into the cause of a stair accident
has often found the incident to be wholly or partly caused by poor stair design. In order to
establish the relationship between the stair design and a given fall, an onsite survey has to be
conducted, determining the rises and goings along with other key dimensions. The Health and
Safety Laboratory (HSL), Buxton, UK, regularly undertake this type of survey using a digital
inclinometer, a steel rule and a tape measure. Laser scanning is an emerging technique that is
now accessible to the surveyor to complement or replace traditional approaches. The laser
scanner and associated software produces a dense point survey in 3D, allowing dimensional
analysis of the features. The authors used both traditional and laser scanning techniques to study
the scenes of two fatal stair falls. The analysis presented allows the suitability of laser scanning for
stair-fall investigation to be considered. Identification and classification of errors are needed in
order to consider if the error is acceptable or can be mitigated. Laser scanners are impressive
instruments providing data from which can be used to create a virtual 3D environment that can be
used to reconstruct and explain an event and contributing factors. The use of both survey
methods currently provides the investigator with complimentary data that allows accurate
measurements to be presented in the context of the three-dimensional environment.European Social Fund (ESF
An optical tweezer array of ultracold polyatomic molecules
Polyatomic molecules have rich structural features that make them uniquely
suited to applications in quantum information science, quantum simulation,
ultracold chemistry, and searches for physics beyond the Standard Model.
However, a key challenge is fully controlling both the internal quantum state
and the motional degrees of freedom of the molecules. Here, we demonstrate the
creation of an optical tweezer array of individual polyatomic molecules, CaOH,
with quantum control of their internal quantum state. The complex quantum
structure of CaOH results in a non-trivial dependence of the molecules'
behavior on the tweezer light wavelength. We control this interaction and
directly and nondestructively image individual molecules in the tweezer array
with >90% fidelity. The molecules are manipulated at the single internal
quantum state level, thus demonstrating coherent state control in a tweezer
array. The platform demonstrated here will enable a variety of experiments
using individual polyatomic molecules with arbitrary spatial arrangement.Comment: 11 pages, 6 figure
Symmetry-mode analysis for local structure investigations using pair distribution function data
Symmetry-adapted distortion modes provide a natural way to describe distorted
structures derived from higher-symmetry parent phases. Structural refinements
using symmetry-mode amplitudes as fit variables have been used for at least 10
years in Rietveld refinements of the average crystal structure from diffraction
data; more recently, this approach has also been used for investigations of the
local structure using real-space pair distribution function (PDF) data. Here,
we further demonstrate the value of performing symmetry-mode fits to PDF data
through the successful application of this method to two topical materials:
TiSe, where we detect the subtle but long-range structural distortion
driven by the formation of a charge density wave, and MnTe, where we
characterize a large but highly localized structural distortion in terms of
symmetry-lowering displacements of the Te atoms. The analysis is performed
using fully open-source code within the DiffPy framework using two packages we
developed for this work: isopydistort, which provides a scriptable interface to
the ISODISTORT web application for group theoretical calculations, and
isopytools, which converts the ISODISTORT output into a DiffPy-compatible
format for subsequent fitting and analysis. These developments expand the
potential impact of symmetry-adapted PDF analysis by enabling high throughput
analysis and removing the need for any commercial software
National survey of feasibility of NIV trials for management of children with bronchiolitis.
Background: Bronchiolitis is a major cause of admission to hospital in children. Non-invasive ventilation (NIV) support with continuous positive airway pressure (CPAP) or high-flow nasal cannula (HFNC) oxygen is routinely used for infants in the UK with bronchiolitis. Objective: To establish UK paediatric practice regarding management of bronchiolitis, and to explore issues pertinent to the design of a potential future randomised controlled trial of NIV. Design: Screening logs were completed in hospitals in England capturing information on paediatric bronchiolitis admissions. An online national survey of clinical practice was disseminated to healthcare professionals (HCPs) across the UK to ascertain current management strategies. Results: Screening logs captured data on 393 infants from 8 hospitals. Reasons for admission were most commonly respiratory distress and/or poor fluid intake. Oxygen was administered for 54% of admissions. Respiratory (CPAP and HFNC) and non-respiratory support administered varied considerably. The national survey was completed by 111 HCPs from 76 hospitals. Data were obtained on criteria used to commence and wean NIV, responsibilities for altering NIV settings, minimum training requirements for staff managing a child on NIV, and numbers of trained staff. Most centres were interested in and capable of running a trial of NIV, even out of normal office hours. Conclusions: Respiratory and non-respiratory management of bronchiolitis in UK centres varies widely. A trial of HFNC oxygen therapy in this group of patients is feasible and HCPs would be willing to randomise patients into such a trial. Future work should focus on defining trial eligibility criteria
An unfolding signifier: London's Baltic Exchange in Tallinn
In the summer of 2007 an unusual cargo arrived at Muuga and Paldiski harbors outside Tallinn. It consisted of nearly 50 containers holding over 1,000 tons of building material ranging from marble columns, staircases and fireplaces, to sculpted allegorical figures, wooden paneling and old-fashioned telephone booths. They were once part of the Baltic Exchange in the City of London. Soon they will become facets of the landscape of Tallinn. The following article charts this remarkable story and deploys this fragmented monument to analyze three issues relating to the Estonian capital: the relocation of the âBronze Soldierâ, the demolition of the Sakala Culture Center, and Tallinnâs future role as European Cultural Capital in 2011
Development of a new shoe/floor slip resistance test rig
A critical appraisal of the Shoe Slip Tester, SST, is discussed the paper. The SST is designed to be a portable and practical alternative to the Ramp tester which is currently considered the Gold Standard in slip resistance testing. Tests identical safety shoe samples were carried out using the SST and RAMP in parallel and the data yielded compared. Data showed that the Shoe Slip Tester yielded higher coefficients of friction. Controlling the data for force applied at shoe impact gave good correlation between the two devices. Recommendations are made to the design of the SST from data in this paper. Recommendations will improve correlation between the two devices. The SST can be said to be a suitable alternative
- âŠ