1,314 research outputs found
Detailed investigation of a vaporising fuel spray. Part 1: Experimental investigation of time averaged spray
A laser tomographic light scattering technique provides rapid and accurate high resolution measurements of droplet sizes, concentrations, and vaporization. Measurements using a computer interfaced thermocouple are presented and it is found that the potential exists for separating gas and liquid temperature measurements and diagnosing local spray density by in situ analysis of the response characteristics of the thermocouple. The thermocouple technique provides a convenient means for measuring mean gas velocity in both hot and cold two phase flows. The experimental spray is axisymmetric and has carefully controlled initial and boundary conditions. The flow is designed to give relatively insignificant transfer of momentum and mass from spray to air flow. The effects of (1) size-dependent droplet dispersion by the turbulence, (2) the initial spatial segregation of droplet sizes during atomization, and (3) the interaction between droplets and coherent large eddies are diagnosed
The trauma memory quality questionnaire:Preliminary development and validation of a measure of trauma memory characteristics for children and adolescents
It has been suggested that post-traumatic stress is related to the nature of an individual's trauma memories. While this hypothesis has received support in adults, few studies have examined this in children and adolescents. This article describes the development and validation of a measure of the nature of children's trauma memories, the Trauma Memory Quality Questionnaire (TMQQ), that might test this hypothesis and be of clinical use. The measure was standardised in two samples, a cross-sectional sample of non-clinic referred secondary school pupils (n=254), and a sample participating in a prospective study of children and adolescents who had attended a hospital Accident and Emergency department following an assault or a road traffic accident (n=106). The TMQQ was found to possess good internal consistency, criterion validity, and construct validity, but test-retest reliability has yet to be established
A Group-Based Yule Model for Bipartite Author-Paper Networks
This paper presents a novel model for author-paper networks, which is based
on the assumption that authors are organized into groups and that, for each
research topic, the number of papers published by a group is based on a
success-breeds-success model. Collaboration between groups is modeled as random
invitations from a group to an outside member. To analyze the model, a number
of different metrics that can be obtained in author-paper networks were
extracted. A simulation example shows that this model can effectively mimic the
behavior of a real-world author-paper network, extracted from a collection of
900 journal papers in the field of complex networks.Comment: 13 pages (preprint format), 7 figure
How can we demonstrate the economic value of Precision Agriculture (PA) practices to New Zealand Agriculture service providers and arable farmers?
The amount of data collected has become a major challenge to the uptake of PA practices in New Zealand.
There is a lack of clear value propositions around some PA practices, e.g. variable rate seeding (VRS).
The importance of calibrating yield monitors, collecting yield data and mapping results has not been realised by farmers.
The goal of the study is to provide economic evidence through yield data mining to encourage the adoption of PA
A Yule-Simon process with memory
The Yule-Simon model has been used as a tool to describe the growth of
diverse systems, acquiring a paradigmatic character in many fields of research.
Here we study a modified Yule-Simon model that takes into account the full
history of the system by means of an hyperbolic memory kernel. We show how the
memory kernel changes the properties of preferential attachment and provide an
approximate analytical solution for the frequency distribution density as well
as for the frequency-rank distribution.Comment: 7 pages, 5 figures; accepted for publication in Europhysics Letter
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