344 research outputs found
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Not in my backyard, but not far away from me: Local acceptance of wind power in China
Local acceptance of wind energy technology has become an important factor to consider when designing local and national wind energy technological innovation policies. Previous studies have investigated the factors that shape the local acceptance of wind power in high-income countries. However, to the best of our knowledge, these factors had not been investigated in China. Utilizing a survey and quantitative analysis, we have identified the factors that are correlated with local acceptance of wind power in China. We conducted our study in the city of Jiuquan, Gansu Province, which currently possesses the largest installed capacity for wind power generation in China. Two factors, namely, perceived economic benefits and perceived environmental costs, influence local acceptance of wind power in China most significantly. Local acceptance of wind power in China can be described as "not in my backyard, but not far away from me". In other words, the acceptance rate is lowest when the source of wind power is located in their village or community, highest when the project is located in their county and city and decreases for projects that are constructed further away
KRILLBASE: a circumpolar database of Antarctic krill and salp numerical densities, 1926–2016
Antarctic krill (Euphausia superba) and salps are major macroplankton contributors to Southern
Ocean food webs and krill are also fished commercially. Managing this fishery sustainably, against a backdrop of
rapid regional climate change, requires information on distribution and time trends. Many data on the abundance
of both taxa have been obtained from net sampling surveys since 1926, but much of this is stored in national
archives, sometimes only in notebooks. In order to make these important data accessible we have collated available
abundance data (numerical density, no.
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
Effective Phone Calls
“Effective Phone Calls” is a practical and accessible course specifically designed to develop students` essential communication and language skills. It is divided into six units, which contain face-to-face with teacher and self-study materials. The course aims to develop both competence and confi-dence in a variety of situations, so that by the end of the period of study students will have acquired the necessary skills to handle almost any kind of call in business setting
Is Cyprideis agrigentina Decima a good palaeosalinometer 1 for the Messinian Salinity Crisis? 2 Morphometrical and geochemical analyses from the Eraclea Minoa section (Sicily)
The living euryhaline species Cyprideis torosa (Jones) undergoes morphometric variations in size,
noding and sieve-pore shape linked to the environmental salinity. In particular it is known that
salinity values around 8-9 psu represent the osmoregulation threshold and also the turning point
between smaller and greater valve dimensions and prevailingly noded against un-noded valves. The
variation of the percentage of round-, elongate- and irregular-shaped sieve-pores on the valves has
shown an empiric logarithmic correlation with the water salinity from 0 to 100 psu. Due to this ecologically cued polymorphism, C. torosa represents 28 an invaluable palaeosalinometer for the
Quaternary brackish basins.
In this paper we attempt to verify whether the ecophenotypical behaviour of the post-evaporitic
Messinian species Cyprideis agrigentina Decima was comparable with that of C. torosa. To reach
this goal, three morphometric characters have been analysed: 1) size variability; 2) noding and
ornamentation; 3) variability of the percentage of the sieve-pore shapes. The palaeoenvironmental
interpretation was made using synecological and geochemical approaches [stable isotopes, trace
elements, Sr-isotopes and natural radioactivity (NRD)]. For this study, the 250 m-thick Messinian
Lago-Mare succession of Eraclea Minoa (Agrigento, Sicily) was chosen for the presence of
monotypic assemblages made only by C. agrigentina for around 70 m of thickness.
The results of the morphometric analyses showed that: 1) size variations are not related to the
salinity changes recognized both from synecological and geochemical analyses; 2) no noded
specimens have been recovered along the section; 3) the salinities calculated on the basis of the
percentage of the sieve-pore shape are not correlated with the salinities inferred from the
synecological and geochemical analyses. Thus in this paper we conclude that C. agrigentina cannot
be considered a palaeosalinometer for the Messinian Salinity Crisis.
There is a correlation of the 13 C and NRD data with the percentages of sieve-pore shapes, linking
them to the oxygen availability at the bottom of the basin
Noise Characterization and Filtering in the MicroBooNE Liquid Argon TPC
The low-noise operation of readout electronics in a liquid argon time
projection chamber (LArTPC) is critical to properly extract the distribution of
ionization charge deposited on the wire planes of the TPC, especially for the
induction planes. This paper describes the characteristics and mitigation of
the observed noise in the MicroBooNE detector. The MicroBooNE's single-phase
LArTPC comprises two induction planes and one collection sense wire plane with
a total of 8256 wires. Current induced on each TPC wire is amplified and shaped
by custom low-power, low-noise ASICs immersed in the liquid argon. The
digitization of the signal waveform occurs outside the cryostat. Using data
from the first year of MicroBooNE operations, several excess noise sources in
the TPC were identified and mitigated. The residual equivalent noise charge
(ENC) after noise filtering varies with wire length and is found to be below
400 electrons for the longest wires (4.7 m). The response is consistent with
the cold electronics design expectations and is found to be stable with time
and uniform over the functioning channels. This noise level is significantly
lower than previous experiments utilizing warm front-end electronics.Comment: 36 pages, 20 figure
Ionization Electron Signal Processing in Single Phase LArTPCs II. Data/Simulation Comparison and Performance in MicroBooNE
The single-phase liquid argon time projection chamber (LArTPC) provides a
large amount of detailed information in the form of fine-grained drifted
ionization charge from particle traces. To fully utilize this information, the
deposited charge must be accurately extracted from the raw digitized waveforms
via a robust signal processing chain. Enabled by the ultra-low noise levels
associated with cryogenic electronics in the MicroBooNE detector, the precise
extraction of ionization charge from the induction wire planes in a
single-phase LArTPC is qualitatively demonstrated on MicroBooNE data with event
display images, and quantitatively demonstrated via waveform-level and
track-level metrics. Improved performance of induction plane calorimetry is
demonstrated through the agreement of extracted ionization charge measurements
across different wire planes for various event topologies. In addition to the
comprehensive waveform-level comparison of data and simulation, a calibration
of the cryogenic electronics response is presented and solutions to various
MicroBooNE-specific TPC issues are discussed. This work presents an important
improvement in LArTPC signal processing, the foundation of reconstruction and
therefore physics analyses in MicroBooNE.Comment: 54 pages, 36 figures; the first part of this work can be found at
arXiv:1802.0870
Materials and Textile Architecture Analyses for Mechanical Counter-Pressure Space Suits using Active Materials
Mechanical counter-pressure (MCP) space suits have the potential to improve the mobility of astronauts as they conduct planetary exploration activities. MCP suits differ from traditional gas-pressurized space suits by applying surface pressure to the wearer using tight-fitting materials rather than pressurized gas, and represent a fundamental change in space suit design. However, the underlying technologies required to provide uniform compression in a MCP garment at sufficient pressures for space exploration have not yet been perfected, and donning and doffing a MCP suit remains a significant challenge. This research effort focuses on the novel use of active material technologies to produce a garment with controllable compression capabilities (up to 30 kPa) to address these problems. We provide a comparative study of active materials and textile architectures for MCP applications; concept active material compression textiles to be developed and tested based on these analyses; and preliminary biaxial braid compression garment modeling results.United States. National Aeronautics and Space Administration (OCT Space Technology Research Fellowship Grant NNX11AM62H)MIT-Portugal Progra
Design and construction of the MicroBooNE Cosmic Ray Tagger system
The MicroBooNE detector utilizes a liquid argon time projection chamber
(LArTPC) with an 85 t active mass to study neutrino interactions along the
Booster Neutrino Beam (BNB) at Fermilab. With a deployment location near ground
level, the detector records many cosmic muon tracks in each beam-related
detector trigger that can be misidentified as signals of interest. To reduce
these cosmogenic backgrounds, we have designed and constructed a TPC-external
Cosmic Ray Tagger (CRT). This sub-system was developed by the Laboratory for
High Energy Physics (LHEP), Albert Einstein center for fundamental physics,
University of Bern. The system utilizes plastic scintillation modules to
provide precise time and position information for TPC-traversing particles.
Successful matching of TPC tracks and CRT data will allow us to reduce
cosmogenic background and better characterize the light collection system and
LArTPC data using cosmic muons. In this paper we describe the design and
installation of the MicroBooNE CRT system and provide an overview of a series
of tests done to verify the proper operation of the system and its components
during installation, commissioning, and physics data-taking
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