2,338 research outputs found
Design of multilayer insulation systems
Analytical models for insulation system heat transfer studies the types of materials best suited for a near solar environment. This multilayer insulation system for spacecraft can operate at temperatures in the 300 to 700 degree K range
Development of techniques and associated instrumentation for high temperature emissivity measurements Quarterly progress report, 30 Sep. - 31 Dec. 1970
Emittance measurement techniques for space shuttle materials in high temperature environmental simulatio
Development of techniques and associated instrumentation for high temperature emissivity measurements
The calibrating and testing procedures for the radiometric emittance measurement apparatus are described. Test results are given for the NBS platinum-rhodium standard (SRM No. 1409), the NBS oxidized Kanthal standard, and the oxidized Rene 41 materials. Results indicate that with the platinum-rhodium standard the measurement system compared with the NBS data to within 0.02 for both total and spectral normal emitttance. Data from the Kanthal strip was consistently higher than NBS values. For oxidized Rene 41, no significant changes in as prepared emittance was observed. The emittance was stable for temperatures up to 1150 K
Serial Correlations in Single-Subject fMRI with Sub-Second TR
When performing statistical analysis of single-subject fMRI data, serial
correlations need to be taken into account to allow for valid inference.
Otherwise, the variability in the parameter estimates might be under-estimated
resulting in increased false-positive rates. Serial correlations in fMRI data
are commonly characterized in terms of a first-order autoregressive (AR)
process and then removed via pre-whitening. The required noise model for the
pre-whitening depends on a number of parameters, particularly the repetition
time (TR). Here we investigate how the sub-second temporal resolution provided
by simultaneous multislice (SMS) imaging changes the noise structure in fMRI
time series. We fit a higher-order AR model and then estimate the optimal AR
model order for a sequence with a TR of less than 600 ms providing whole brain
coverage. We show that physiological noise modelling successfully reduces the
required AR model order, but remaining serial correlations necessitate an
advanced noise model. We conclude that commonly used noise models, such as the
AR(1) model, are inadequate for modelling serial correlations in fMRI using
sub-second TRs. Rather, physiological noise modelling in combination with
advanced pre-whitening schemes enable valid inference in single-subject
analysis using fast fMRI sequences
Boman v. Elkanich, 140 Nev. Adv. Op. 21 (Apr. 25, 2024)
The Nevada Supreme Court determined when a patient is on inquiry notice as to their legal injury and if the patient’s degree of diligence is diminished while undergoing treatment from the negligent physician. A patient discovers their injury when they recognize the damage suffered and understand the health care provider negligent cause their injury. It found that a patient has a reduced degree of diligence to discover the harm while under the physician’s care, particularly if the physician reassures the patient that they will improve. This left genuine, factual disputes as to when Appellant should have known of the Defendant’s negligence, which is a question for the jury or trier of fact to decide
Adults Recovering from Childhood Sexual Abuse: A Salutogenic Approach
There is a great deal of research into multiple aspects of childhood sexual abuse, including prevalence, effects, treatment and recovery. However, very little research focusses on the knowledge held by people who have experienced CSA, and far fewer studies are designed by people who have experienced it.
This thesis outlines insider designed and delivered research. It employs a salutogenic approach to examine what helps and hinders recovering. These issues are explored through thematic analysis of a qualitative survey (n=140) and 21 interviews. Participants described three types of harm caused by the abuse they had experienced, including physical and mental health consequences but also an underlying, enduring sense of danger.
The results demonstrate that adults who have experienced CSA are active in their recovering, which they conceptualise as a movement towards health and well-being, rather than a binary of either being ill or well. Health services were very useful, particularly counselling and therapy. Respondents also valued personal relationships and interactions in supporting recovering. Finally, they described a sense of flow, a pleasurable absorption in a task, as being highly beneficial.
However, they also described the ways in which society, at every level from micro to macro, inhibited recovering. Thus, they called for fundamental societal change, challenging destructive discourses around CSA and inhibiting structural issues. Further research is required to establish if these beneficial actions and challenges apply equally to individuals who identify as being in earlier stages of recovering
Detecting the power spectrum turnover with Hi intensity mapping
A goal for pathfinder intensity mapping (IM) surveys will be detecting
features in the neutral hydrogen (HI) power spectrum, which serve as conclusive
evidence of cosmological signals. Observing such features at the expected
scales in HI IM auto-correlations, where contribution from systematics is
uncertain, will provide a more convincing cosmological detection. We
demonstrate how the turnover, i.e. the peak of the power spectrum at
ultra-large scales, can be detected with HI IM. We find that a MeerKAT
4,000 survey using the UHF-band is capable of a
detection of the turnover, relative to a null model power spectrum with no
turnover. This should exceed what is capable by current galaxy surveys in
optical and near-infrared. The detection significance falls to
in MeerKAT's L-band but can reach with the SKAO, which should
easily surpass the constraints from future Stage-IV-like spectroscopic galaxy
surveys. We also propose a new model-independent methodology for constraining
the precise turnover scale () and our tests on UHF-band simulated data
achieved a precision of 10%. This improved to 2.4% when using the full SKAO. We
demonstrate how the results are robust to foreground contamination by using
transfer functions, even when an incorrect cosmology has been assumed in their
construction. Given that the turnover is related to the horizon scale at
matter-radiation equality, a sufficiently precise constraint of presents
the possibility for a novel probe of cosmology. We therefore present a
potential methodology for constructing a standard-ruler-based distance
measurement, independent of the sound horizon, using the turnover location in
the HI power spectrum.Comment: 18 pages, 10 figures. See Fig 4 for main forecast of turnover
detection for different HI IM surveys. See Fig 7 for constraints possible on
turnover scale and Fig 8 for demo of how this can be used for cosmology.
Accepted for publication in MNRAS. Minor grammatical edits made for V2 in
response to editors' final proof
In re Search Warrants re Seizure of Docs (Hustler Club), 139 Nev. Adv. Op. 23 (Aug. 24, 2023)
The Court of Appeals for the State of Nevada found that the district court properly used its discretion to find probable cause for the search warrants and to keep them sealed. The district court erred when it denied the appellants’ request to return its property because the appellants were not able to properly demonstrate privilege
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