10 research outputs found
Experimental study of a flexible and environmentally stable electroadhesive device
Electroadhesion is a promising adhesion mechanism for robotics and material handling applications due to several distinctive advantages it has over existing technologies. These advantages include enhanced adaptability, gentle/flexible handling, reduced complexity, and ultralow
energy consumption. Unstable electroadhesive forces, however, can arise in ambient environments. Electroadhesive devices that can produce stable forces in changing environments are thus desirable. In this study, a flexible and environmentally stable electroadhesive device was designed and manufactured by conformally coating a layer of barium titanate dielectric on a chemically etched thin copper laminate. The results, obtained from an advanced electroadhesive “normal force” testing platform, show that only a relative difference of 5.94% in the normal force direction was observed. This was achieved when the relative humidity changed from 25% to 53%, temperature from 13.7 �C to 32.8 �C, and atmospheric pressure from 999 hPa to 1016.9 hPa. This environmentally stable electroadhesive device may promote the application of the electroadhesion technology
Constraints on Type Ia Supernova Progenitor Companions from Early Ultraviolet Observations with Swift
We compare early ultraviolet (UV) observations of Type Ia Supernovae (SNe Ia)
with theoretical predictions for the brightness of the shock associated with
the collision between SN ejecta and a companion star. Our simple method is
independent of the intrinsic flux from the SN and treats the flux observed with
the Swift/Ultra-Violet Optical Telescope (UVOT) as conservative upper limits on
the shock brightness. Comparing this limit with the predicted flux for various
shock models, we constrain the geometry of the SN progenitor-companion system.
We find the model of a 1 M_sun red supergiant companion in Roche lobe overflow
to be excluded at a 95% confidence level for most individual SNe for all but
the most unfavorable viewing angles. For the sample of 12 SNe taken together,
the upper limits on the viewing angle are inconsistent with the expected
distribution of viewing angles for RG stars as the majority of companions with
high confidence. The separation distance constraints do allow MS companions. A
better understanding of the UV flux arising from the SN itself as well as
continued UV observations of young SNe Ia will further constrain the possible
progenitors of SNe Ia.Comment: accepted versio
Probability and inferential statistics
An introduction to probability and the probability of sample errors affecting research results
Levels of Measurement
To understand the different levels of measurement including nominal, ration, ordinal and scale measurements and the arithmetic operations that can be performed on them
Descriptive statistics for interval and ratio scale
Describes the use of measures of central tendency, mean, mode, median and dispersion - range, standard deviation
Levels of Measurement - what you can and can't do arithmetically
An explanation of the statistical operations that can be performed on the different levels of measurement.
The Next Generation Global Gravitational Wave Observatory: The Science Book
The next generation of ground-based gravitational-wave detectors will observe coalescences of black holes and neutron stars throughout the cosmos, thousands of them with exceptional fidelity. The Science Book is the result of a 3-year effort to study the science capabilities of networks of next generation detectors. Such networks would make it possible to address unsolved problems in numerous areas of physics and astronomy, from Cosmology to Beyond the Standard Model of particle physics, and how they could provide insights into workings of strongly gravitating systems, astrophysics of compact objects and the nature of dense matter. It is inevitable that observatories of such depth and finesse will make new discoveries inaccessible to other windows of observation. In addition to laying out the rich science potential of the next generation of detectors, this report provides specific science targets in five different areas in physics and astronomy and the sensitivity requirements to accomplish those science goals. This report is the second in a six part series of reports by the GWIC 3G Subcommittee: i) Expanding the Reach of Gravitational Wave Observatories to the Edge of the Universe, ii) The Next Generation Global Gravitational Wave Observatory: The Science Book (this report), iii) 3G R&D: R&D for the Next Generation of Ground-based Gravitational Wave Detectors, iv) Gravitational Wave Data Analysis: Computing Challenges in the 3G Era, v) Future Ground-based Gravitational-wave Observatories: Synergies with Other Scientific Communities, and vi) An Exploration of Possible Governance Models for the Future Global Gravitational-Wave Observatory Network
The Next Generation Global Gravitational Wave Observatory: The Science Book
The next generation of ground-based gravitational-wave detectors will observe coalescences of black holes and neutron stars throughout the cosmos, thousands of them with exceptional fidelity. The Science Book is the result of a 3-year effort to study the science capabilities of networks of next generation detectors. Such networks would make it possible to address unsolved problems in numerous areas of physics and astronomy, from Cosmology to Beyond the Standard Model of particle physics, and how they could provide insights into workings of strongly gravitating systems, astrophysics of compact objects and the nature of dense matter. It is inevitable that observatories of such depth and finesse will make new discoveries inaccessible to other windows of observation. In addition to laying out the rich science potential of the next generation of detectors, this report provides specific science targets in five different areas in physics and astronomy and the sensitivity requirements to accomplish those science goals. This report is the second in a six part series of reports by the GWIC 3G Subcommittee: i) Expanding the Reach of Gravitational Wave Observatories to the Edge of the Universe, ii) The Next Generation Global Gravitational Wave Observatory: The Science Book (this report), iii) 3G R&D: R&D for the Next Generation of Ground-based Gravitational Wave Detectors, iv) Gravitational Wave Data Analysis: Computing Challenges in the 3G Era, v) Future Ground-based Gravitational-wave Observatories: Synergies with Other Scientific Communities, and vi) An Exploration of Possible Governance Models for the Future Global Gravitational-Wave Observatory Network