495 research outputs found
Exploratory tests of a simple aero-mechanical ride comfort system for lightly loaded aircraft
Some exploratory wind tunnel and radio-controlled free-flight tests were made with a small high-wing airplane model (1.23m wing span) to study the concept of a simple aero mechanical system intended to alleviate gust loads and improve ride comfort of lightly loaded aircraft. The system consisted essentially of the outer portions of each wing being hinged in the chordwise direction and connected directly to the wing flaps using internal counter weights to provide neutral mass balance. When the wing experienced a change in velocity or angle of attack, the movable wing panels, acting as sensors and flap actuators, deflected in response to the changes in lift on the wing. The corresponding movements of the interconnected flaps tended to reduce the changes in the wing lift
Gust alleviation system to improve ride comfort of light airplanes
System consists of movable auxiliary aerodynamic sensors mounted on fuselage and connected to trailing-edge flaps by rigid mechanical linkages. System achieves alleviation by reducing lift-curve slope of airplane to such a small value that gust-induced angles of attack will result in small changes in lift
Low power, compact charge coupled device signal processing system
A variety of charged coupled devices (CCDs) for performing programmable correlation for preprocessing environmental sensor data preparatory to its transmission to the ground were developed. A total of two separate ICs were developed and a third was evaluated. The first IC was a CCD chirp z transform IC capable of performing a 32 point DFT at frequencies to 1 MHz. All on chip circuitry operated as designed with the exception of the limited dynamic range caused by a fixed pattern noise due to interactions between the digital and analog circuits. The second IC developed was a 64 stage CCD analog/analog correlator for performing time domain correlation. Multiplier errors were found to be less than 1 percent at designed signal levels and less than 0.3 percent at the measured smaller levels. A prototype IC for performing time domain correlation was also evaluated
Take the Monkey and Run
The common marmoset (Callithrix jacchus) is a small, New World primate that is used extensively in biomedical and behavioral research. This short-lived primate, with its small body size, ease of handling, and docile temperament, has emerged as a valuable model for aging and neurodegenerative research. A growing body of research has indicated exercise, aerobic exercise especially, imparts beneficial effects to normal aging. Understanding the mechanisms underlying these positive effects of exercise, and the degree to which exercise has neurotherapeutic effects, is an important research focus. Thus, developing techniques to engage marmosets in aerobic exercise would have great advantages
Natural iron enrichment around the Antarctic Peninsula in the Southern Ocean
As part of the US-AMLR program in January-February of 2006, 99 stations in
the South Shetland Islands-Antarctic Peninsula region were sampled to
understand the variability in hydrographic and biological properties related
to the abundance and distribution of krill in this area. Concentrations of
dissolved iron (DFe) and total acid-leachable iron (TaLFe) were measured in
the upper 150 m at 16 of these stations (both coastal and pelagic waters) to
better resolve the factors limiting primary production in this area and in
downstream waters of the Scotia Sea. The concentrations of DFe and TaLFe in
the upper mixed layer (UML) were relatively high in Weddell Sea Shelf Waters
(~0.6 nM and 15 nM, respectively) and low in Drake Passage waters
(~0.2 nM and 0.9 nM, respectively). In the Bransfield
Strait, representing a mixture of waters from the Weddell Sea and the
Antarctic Circumpolar Current (ACC), concentrations of DFe were ~0.4 nM
and of TaLFe ~1.7 nM. The highest concentrations of DFe and TaLFe
in the UML were found at shallow coastal stations close to Livingston Island
(~1.6 nM and 100 nM, respectively). The ratio of TaLFe:DFe varied
with the distance to land: ~45 at the shallow coastal stations, ~15
in the high-salinity waters of Bransfield Strait, and ~4 in ACC
waters. Concentrations of DFe increased slightly with depth in the water
column, while that of TaLFe did not show any consistent trend with depth.
Our Fe data are discussed in regard to the hydrography and water circulation
patterns in the study area, and with the hypothesis that the relatively high
rates of primary production in the central regions of the Scotia Sea are
partially sustained by natural iron enrichment resulting
from a northeasterly flow of iron-rich coastal waters originating in
the South Shetland Islands-Antarctic Peninsula region
The Impact of Immersive Outdoor Activities in Local Woodlands on Young Carers Emotional Literacy and Well-Being
Children’s well-being is linked to a complex web of factors including the child’s personality, inherent protective mechanisms, family relationships, social capital, and economic status. Young carers are particularly at risk from poor mental health outcomes and low well-being. In this study the impact of immersive activities in nature on the well-being of 8 young carers (3 girls and 5 boys; aged 9–13 years) was explored. The immersive woodland activities included practical skills such as fire making, cooking, and using tools as well as team building and activities to help build trust. A mixed method, pre-test/post-test approach was undertaken using Emotional Literacy Checklists and interviews, poems and discussion. There were measurable improvements—specifically in motivation and self-awareness—in the young carers’ emotional literacy as reported by the parents and teachers. The well-being indicators that were referenced most frequently by parents and teachers related to the children’s social relationships and their development as individuals. The children reported changes related to social, physical, and “natural connection” well-being
Experiment Simulation Configurations Used in DUNE CDR
The LBNF/DUNE CDR describes the proposed physics program and experimental
design at the conceptual design phase. Volume 2, entitled The Physics Program
for DUNE at LBNF, outlines the scientific objectives and describes the physics
studies that the DUNE collaboration will perform to address these objectives.
The long-baseline physics sensitivity calculations presented in the DUNE CDR
rely upon simulation of the neutrino beam line, simulation of neutrino
interactions in the far detector, and a parameterized analysis of detector
performance and systematic uncertainty. The purpose of this posting is to
provide the results of these simulations to the community to facilitate
phenomenological studies of long-baseline oscillation at LBNF/DUNE.
Additionally, this posting includes GDML of the DUNE single-phase far detector
for use in simulations. DUNE welcomes those interested in performing this work
as members of the collaboration, but also recognizes the benefit of making
these configurations readily available to the wider community.Comment: 9 pages, 4 figures, configurations in ancillary file
Recommended from our members
The Pandora multi-algorithm approach to automated pattern recognition of cosmic-ray muon and neutrino events in the MicroBooNE detector.
The development and operation of liquid-argon time-projection chambers for neutrino physics has created a need for new approaches to pattern recognition in order to fully exploit the imaging capabilities offered by this technology. Whereas the human brain can excel at identifying features in the recorded events, it is a significant challenge to develop an automated, algorithmic solution. The Pandora Software Development Kit provides functionality to aid the design and implementation of pattern-recognition algorithms. It promotes the use of a multi-algorithm approach to pattern recognition, in which individual algorithms each address a specific task in a particular topology. Many tens of algorithms then carefully build up a picture of the event and, together, provide a robust automated pattern-recognition solution. This paper describes details of the chain of over one hundred Pandora algorithms and tools used to reconstruct cosmic-ray muon and neutrino events in the MicroBooNE detector. Metrics that assess the current pattern-recognition performance are presented for simulated MicroBooNE events, using a selection of final-state event topologies
The Pandora multi-algorithm approach to automated pattern recognition of cosmic-ray muon and neutrino events in the MicroBooNE detector
The development and operation of Liquid-Argon Time-Projection Chambers for
neutrino physics has created a need for new approaches to pattern recognition
in order to fully exploit the imaging capabilities offered by this technology.
Whereas the human brain can excel at identifying features in the recorded
events, it is a significant challenge to develop an automated, algorithmic
solution. The Pandora Software Development Kit provides functionality to aid
the design and implementation of pattern-recognition algorithms. It promotes
the use of a multi-algorithm approach to pattern recognition, in which
individual algorithms each address a specific task in a particular topology.
Many tens of algorithms then carefully build up a picture of the event and,
together, provide a robust automated pattern-recognition solution. This paper
describes details of the chain of over one hundred Pandora algorithms and tools
used to reconstruct cosmic-ray muon and neutrino events in the MicroBooNE
detector. Metrics that assess the current pattern-recognition performance are
presented for simulated MicroBooNE events, using a selection of final-state
event topologies.Comment: Preprint to be submitted to The European Physical Journal
Determination of muon momentum in the MicroBooNE LArTPC using an improved model of multiple Coulomb scattering
We discuss a technique for measuring a charged particle's momentum by means
of multiple Coulomb scattering (MCS) in the MicroBooNE liquid argon time
projection chamber (LArTPC). This method does not require the full particle
ionization track to be contained inside of the detector volume as other track
momentum reconstruction methods do (range-based momentum reconstruction and
calorimetric momentum reconstruction). We motivate use of this technique,
describe a tuning of the underlying phenomenological formula, quantify its
performance on fully contained beam-neutrino-induced muon tracks both in
simulation and in data, and quantify its performance on exiting muon tracks in
simulation. Using simulation, we have shown that the standard Highland formula
should be re-tuned specifically for scattering in liquid argon, which
significantly improves the bias and resolution of the momentum measurement.
With the tuned formula, we find agreement between data and simulation for
contained tracks, with a small bias in the momentum reconstruction and with
resolutions that vary as a function of track length, improving from about 10%
for the shortest (one meter long) tracks to 5% for longer (several meter)
tracks. For simulated exiting muons with at least one meter of track contained,
we find a similarly small bias, and a resolution which is less than 15% for
muons with momentum below 2 GeV/c. Above 2 GeV/c, results are given as a first
estimate of the MCS momentum measurement capabilities of MicroBooNE for high
momentum exiting tracks
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