1,010 research outputs found
Fuel cells for power generation and organic waste treatment on the island of Mull
In-situ use of biomass and organic waste streams have the potential to provide the key to energy self sustainability for islands and remote communities. Traditionally biogas fuels have been used in combustion engines for electric power generation. However, fuel cells offer the prospect of achieving higher generating efficiencies, and additionally, important environmental benefits can be achieved by way of mitigating greenhouse gas emissions, whilst providing a carbon sink. This paper presents the design details of a biogas gas plant and fuel cell installation that will provide a practical solution on an island (and be applicable in other remote and rural areas) where connection to the grid can be expensive, and where biofuels can be produced on site at no significant extra cost
Survival and Recruitment of Rehabilitated Caspian Terns in Southern California
Thousands of birds are taken in by animal care centers each year for rehabilitation. Birds returned to health by some centers are banded for later identification, but very few are ever reencountered following their return to the wild. We report here, information on the post-release survival of Caspian Terns (Hydroprogne caspia) in southern California as well as on their recruitment into a local breeding population and colony site fidelity
Bringing Salary Transparency to the World: Computing Robust Compensation Insights via LinkedIn Salary
The recently launched LinkedIn Salary product has been designed with the goal
of providing compensation insights to the world's professionals and thereby
helping them optimize their earning potential. We describe the overall design
and architecture of the statistical modeling system underlying this product. We
focus on the unique data mining challenges while designing and implementing the
system, and describe the modeling components such as Bayesian hierarchical
smoothing that help to compute and present robust compensation insights to
users. We report on extensive evaluation with nearly one year of de-identified
compensation data collected from over one million LinkedIn users, thereby
demonstrating the efficacy of the statistical models. We also highlight the
lessons learned through the deployment of our system at LinkedIn.Comment: Conference information: ACM International Conference on Information
and Knowledge Management (CIKM 2017
The Injector Layout of BERLinPro
BERLinPro is an Energy Recovery Linac Project running since 2011 at the HZB in Berlin. A conceptual design report has been published in 2012 [1]. One of the key components of the project is the 100 mA superconducting RF photocathode gun under development at the HZB since 2010. Starting in 2016 the injector will go into operation, providing 6.6 MeV electrons with an emittance well below 1mm mrad and bunches shorter than 5 ps. In 2017 the 50 MeV linac will be set up and full recirculation is planned for 2018. The injector design has been finalized and is described in detail in this paper. Emphasis is further laid on beam dynamics aspects and performance simulations of two different gun cavitie
Shot noise in lithographically patterned graphene nanoribbons
We have investigated shot noise and conductance of multiterminal graphene nanoribbon devices at temperatures down to 50 mK. Away from the charge neutrality point, we find a Fano factor F≈0.4, nearly independent of the charge density. Our shot noise results are consistent with theoretical models for disordered graphene ribbons with a dimensionless scattering strength K0 ≈ 10 corresponding to rather strong disorder. Close to charge neutrality, an increase in F up to ∼0.7 is found, which indicates the presence of a dominant Coulomb gap possibly due to a single quantum dot in the transport gap.Peer reviewe
The star-forming content of the W3 giant molecular cloud
We have surveyed a ~0.9-square-degree area of the W3 giant molecular cloud
and star-forming region in the 850-micron continuum, using the SCUBA bolometer
array on the James Clerk Maxwell Telescope. A complete sample of 316 dense
clumps was detected with a mass range from around 13 to 2500 Msun. Part of the
W3 GMC is subject to an interaction with the HII region and fast stellar winds
generated by the nearby W4 OB association. We find that the fraction of total
gas mass in dense, 850-micron traced structures is significantly altered by
this interaction, being around 5% to 13% in the undisturbed cloud but ~25 - 37%
in the feedback-affected region. The mass distribution in the detected clump
sample depends somewhat on assumptions of dust temperature and is not a simple,
single power law but contains significant structure at intermediate masses.
This structure is likely to be due to crowding of sources near or below the
spatial resolution of the observations. There is little evidence of any
difference between the index of the high-mass end of the clump mass function in
the compressed region and in the unaffected cloud. The consequences of these
results are discussed in terms of current models of triggered star formation.Comment: 13 pages, 8 figures, 1 table (full source table available on
request). Accepted for publication in Monthly Notices of the Royal
Astronomical Society (Main Journal
Dirac Sea Effects on Superfluidity in Nuclear Matter
We study two kinds of Dirac sea effects on the pairing gap in nuclear
matter based on the relativistic Hartree approximation to quantum hadrodynamics
and the Gor'kov formalism. We show that the vacuum fluctuation effect on the
nucleon effective mass is more important than the direct coupling between the
Fermi sea and the Dirac sea due to the pairing interaction. The effects of the
high-momentum cutoff are also discussed.Comment: 11 pages, 3 eps figures included, uses REVTeX (with \tightenlines
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