1,463 research outputs found
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Measured Water Temperature Characteristics in a Pipeline Distribution System
YesThis paper describes the design, development, deployment and performance assessment of a
prototype system for monitoring the 'health' of a water distribution network based on the
temperature distribution and time-dependent variations in temperature across the network. It
has been found that the water temperature can reveal unusual events in a water distribution
network, indicated by dynamic variations in spatial temperature differential. Based on this
indication it is shown how patterns of changes in the water temperature can be analysed using
AQUIS pipeline distribution software and used in conjunction with hydraulic (e.g. flow and
pressure) sensors to indicate the state of ¿health¿ of the network during operation
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Artificial Neural Network Model for a Low Cost Failure Sensor: Performance Assessment in Pipeline Distribution
YesThis paper describes an automated event detection and
location system for water distribution pipelines which is based upon
low-cost sensor technology and signature analysis by an Artificial
Neural Network (ANN). The development of a low cost failure
sensor which measures the opacity or cloudiness of the local water
flow has been designed, developed and validated, and an ANN based
system is then described which uses time series data produced by
sensors to construct an empirical model for time series prediction and
classification of events. These two components have been installed,
tested and verified in an experimental site in a UK water distribution
system. Verification of the system has been achieved from a series of
simulated burst trials which have provided real data sets. It is
concluded that the system has potential in water distribution network
management
Looking to thefuture
Panel discussion by speakers on their expectations, impressions and take-away message of the meeting
Magnetic field dependence of the internal quality factor and noise performance of lumped-element kinetic inductance detectors
We present a technique for increasing the internal quality factor of kinetic
inductance detectors (KIDs) by nulling ambient magnetic fields with a properly
applied magnetic field. The KIDs used in this study are made from thin-film
aluminum, they are mounted inside a light-tight package made from bulk
aluminum, and they are operated near . Since the thin-film
aluminum has a slightly elevated critical temperature (), it therefore transitions before the package (), which also serves as a magnetic shield. On cooldown, ambient
magnetic fields as small as approximately can produce
vortices in the thin-film aluminum as it transitions because the bulk aluminum
package has not yet transitioned and therefore is not yet shielding. These
vortices become trapped inside the aluminum package below
and ultimately produce low internal quality factors in the thin-film
superconducting resonators. We show that by controlling the strength of the
magnetic field present when the thin film transitions, we can control the
internal quality factor of the resonators. We also compare the noise
performance with and without vortices present, and find no evidence for excess
noise beyond the increase in amplifier noise, which is expected with increasing
loss.Comment: 5 pages, 4 figure
Direct and mediated effects of a social-emotional and character development program on adolescent substance use
Mitigating and preventing substance use among adolescents requires approaches that
address the multitude of factors that influence this behavior. Such approaches must be
tested, not only for evidence of empirical effectiveness, but also to determine the
mechanisms by which they are successful. The aims of the present study were twofold:
1) To determine the effectiveness of a school-based social-emotional and character
development (SECD) program, Positive Action (PA), in reducing substance use (SU)
among a sample of U.S. youth living in a low-income, urban environment, and 2) to test
one mechanism by which the program achieves its success. We used longitudinal
mediation analysis to test the hypotheses that: 1) students attending PA intervention
schools engage in significantly less SU than students attending control schools, 2)
students attending PA intervention schools show significantly better change in SECD
than students attending control schools, and 3) the effect of the PA intervention on SU is
mediated by the change in SECD. Analyses revealed program effects on both SECD and
SU, a relationship between SECD and SU, and the effects of PA on SU were completely
mediated by changes in SECD. Future research directions and implications for schoolbased social-emotional and character development efforts and substance use prevention are addressed.peer-reviewe
Fluoxetine prevents development of an early stress-related molecular signature in the rat infralimbic medial prefrontal cortex : implications for depression?
Background: Psychological stress, particularly in chronic form, can lead to mood and cognitive dysfunction and is a major risk factor in the development of depressive states. How stress affects the brain to cause psychopathologies is incompletely understood. We sought to characterise potential depression related mechanisms by analysing gene expression and molecular pathways in the infralimbic medial prefrontal cortex (ILmPFC), following a repeated psychological stress paradigm. The ILmPFC is thought to be involved in the processing of emotionally contextual information and in orchestrating the related autonomic responses, and it is one of the brain regions implicated in both stress responses and depression. Results: Genome-wide microarray analysis of gene expression showed sub-chronic restraint stress resulted predominantly in a reduction in transcripts 24 hours after the last stress episode, with 239 genes significantly decreased, while just 24 genes had increased transcript abundance. Molecular pathway analysis using DAVID identified 8 pathways that were significantly enriched in the differentially expressed gene list, with genes belonging to the brain-derived neurotrophic factor – neurotrophin receptor tyrosine kinase 2 (BDNF-Ntrk2) pathway most enriched. Of the three intracellular signalling pathways that are downstream of Ntrk2, real-time quantitative PCR confirmed that only the PI3K-AKT-GSK3B and MAPK/ERK pathways were affected by sub-chronic stress, with the PLCγ pathway unaffected. Interestingly, chronic antidepressant treatment with the selective serotonin reuptake inhibitor, fluoxetine, prevented the stress-induced Ntrk2 and PI3K pathway changes, but it had no effect on the MAPK/ERK pathway. Conclusions: These findings indicate that abnormal BDNF-Ntrk2 signalling may manifest at a relatively early time point, and is consistent with a molecular signature of depression developing well before depression-like behaviours occur. Targeting this pathway prophylactically, particularly in depression-susceptible individuals, may be of therapeutic benefit
A millimeter-wave kinetic inductance detector camera for long-range imaging through optical obscurants
Millimeter-wave imaging provides a promising option for long-range target detection through optical obscurants such as fog, which often occur in marine environments. Given this motivation, we are currently developing a 150 GHz polarization-sensitive imager using a relatively new type of superconducting pair-breaking detector, the kinetic inductance detector (KID). This imager will be paired with a 1.5 m telescope to obtain an angular resolution of 0.09° over a 3.5° field of view using 3,840 KIDs. We have fully characterized a prototype KID array, which shows excellent performance with noise strongly limited by the irreducible fluctuations from the ambient temperature background. Full-scale KID arrays are now being fabricated and characterized for a planned demonstration in a maritime environment later this year
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