University of Portsmouth

About: University of Portsmouth is a education organization based out in Portsmouth, Portsmouth, United Kingdom. It is known for research contribution in the topics: Population & Galaxy. The organization has 5452 authors who have published 14256 publications receiving 424346 citations. The organization is also known as: Portsmouth and Gosport School of Science and Art & Portsmouth and Gosport School of Science and the Arts.

Recycling of polyamide 12 based powders in the laser sintering process

Abstract: Purpose – The purpose of this paper is to investigate the polyamide 12 (PA12) powder properties deterioration in the laser sintering (LS) process and propose a methodology for more efficient powder recycling. The main goals are: to recommend a level of input PA2200 powder properties which could guarantee acceptable part quality in the LS process; and selection of the refresh rate in order to minimise the consumption of fresh material.Design/methodology/approach – The paper analyses the LS processing conditions and current recycling practices in relation to the deterioration or ageing of the PA12‐based powders. Samples of new and recycled grades of PA2200 powder were artificially aged in a temperature‐controlled oven and then tested using melt flow rate (MFR) indexer. Also, un‐sintered powder samples collected from different locations within various builds, and different LS machines (EOSINT P700 and Sinterstation® 2500 HiQ) were tested.Findings – The powder exposed at higher temperature and longer time exp...

Utility of multimaterial 3D printers in creating models with pathological entities to enhance the training experience of neurosurgeons.

Abstract: The advent of multimaterial 3D printers allows the creation of neurosurgical models of a more realistic nature, mimicking real tissues. The authors used the latest generation of 3D printer to create a model, with an inbuilt pathological entity, of varying consistency and density. Using this model the authors were able to take trainees through the basic steps, from navigation and planning of skin flap to performing initial steps in a craniotomy and simple tumor excision. As the technology advances, models of this nature may be able to supplement the training of neurosurgeons in a simulated operating theater environment, thus improving the training experience.

A guide to LIGO–Virgo detector noise and extraction of transient gravitational-wave signals

Abstract: The LIGO Scientific Collaboration and the Virgo Collaboration have cataloged eleven confidently detected gravitational-wave events during the first two observing runs of the advanced detector era. All eleven events were consistent with being from well-modeled mergers between compact stellar-mass objects: black holes or neutron stars. The data around the time of each of these events have been made publicly available through the gravitational-wave open science center. The entirety of the gravitational-wave strain data from the first and second observing runs have also now been made publicly available. There is considerable interest among the broad scientific community in understanding the data and methods used in the analyses. In this paper, we provide an overview of the detector noise properties and the data analysis techniques used to detect gravitational-wave signals and infer the source properties. We describe some of the checks that are performed to validate the analyses and results from the observations of gravitational-wave events. We also address concerns that have been raised about various properties of LIGO–Virgo detector noise and the correctness of our analyses as applied to the resulting data.

A comparison of mainstream and special education for teenagers with Down syndrome: implications for parents and teachers.

Abstract: This article presents data from a research study designed to compare the achievements of teenagers with Down syndrome educated in mainstream classrooms or in special education classrooms throughout their full-time education. Progress is reported for speech and language, literacy, socialisation, daily living skills and behaviour. For all the teenagers, there is evidence of progress with age on all the measures except for communication. Communication continued to improve through teenage years for the included children but not for those in special education classrooms. There were no significant differences in overall outcomes for daily living skills or socialisation. However, there were large significant gains in expressive language and literacy skills for those educated in mainstream classrooms. Teenagers educated in mainstream classrooms showed fewer behavioural difficulties. Further, comparison with data published by these authors in an earlier study, showed no improvements in school achievements in special education over a 13 year period in the UK (1986-1999).