814 research outputs found
Design of a "Digital Atlas Vme Electronics" (DAVE) Module
ATLAS-SCT has developed a new ATLAS trigger card, 'Digital Atlas Vme
Electronics' ("DAVE"). The unit is designed to provide a versatile array of
interface and logic resources, including a large FPGA. It interfaces to both
VME bus and USB hosts. DAVE aims to provide exact ATLAS CTP (ATLAS Central
Trigger Processor) functionality, with random trigger, simple and complex
deadtime, ECR (Event Counter Reset), BCR (Bunch Counter Reset) etc. being
generated to give exactly the same conditions in standalone running as
experienced in combined runs. DAVE provides additional hardware and a large
amount of free firmware resource to allow users to add or change functionality.
The combination of the large number of individually programmable inputs and
outputs in various formats, with very large external RAM and other components
all connected to the FPGA, also makes DAVE a powerful and versatile FPGA
utility cardComment: 8 pages, 4 figures, TWEPP-2011; E-mail: [email protected]
An interdisciplinary analysis of ERTS data for Colorado mountain environments using ADP techniques. An early analysis of ERTS-1 data
There are no author-identified significant results in this report. The principal problem encountered has been the lack of good quality, small scale baseline photography for the test areas. Analysis of the ERTS-1 data for the San Juan Site will emphasize development of a preliminary spectral classification defining grass cover categories, and then selection of subframes for intensive investigation of the forestry, geologic, and hydrologic properties of the area. Primary work has been devoted to the selection and digitization of areas for topographic modeling, and compilation of ground based data maps necessary for computer analysis. Study effort has emphasized: geomorphic features; macro-vegetation; micro-vegetation; snow-hydrology; insect/disease damage; and blow-down. Analysis of a frame of the Lake Texoma area indicates a great deal of potential in the analysis and interpretation of ERTS imagery. Preliminary results of investigations of geologic, forest, range, cropland, and water resources of the area are summarized
Explaining the imbalance in ÎŽ13C between soil and biomass in fire-prone tropical savannas
Currently, models of terrestrial 13C discrimination indicate that about one quarter of the gross primary productivity (GPP - total carbon fixed as biomass by plants) by the terrestrial biosphere is attributable to tropical savanna/grassland plants that use the C, photosynthetic pathway. However, the fraction of C,-derived biomass in soil organic carbon in savanna systems is much lower than these GPP estimates imply. Determining this imbalance has significant implications for correctly interpreting soil and palaeosol carbon isotope data, and for modelling studies that use variations in the atmospheric ÎŽ13CO, record to apportion sources and sinks of carbon. Here, we present preliminary results using hydrogen pyrolysis (HyPy) for quantifying the abundance and identifying the source of pyrogenic carbon (PC) in tropical savannas of North Queensland (Australia). We collected sediment from a series of micro-catchments covering the broadest possible range of C, and C, environments, and compared the abundances and stable isotope compositions of the total organic carbon (TOC) and pyrogenic carbon (PC) fractions.
Hydrogen pyrolysis (HyPy) can be used to quantify the production, fate and stable isotope composition of PC produced by vegetation burning. HyPy is pyrolysis (up to ~600°C) under high hydrogen pressures (>10 MPa) in the presence of a catalyst, and when applied to sediments, soils, or organic samples results in the reductive removal of labile organic matter. Therefore, this technique offers great potential to effectively isolate and quantify pyrogenic carbon in a rapid and cost effective manner. Moreover, comparison of the stable carbon isotope composition of PC with bulk carbon has the potential to discern if there is a dominant vegetation source contributing to burning.
The results indicate that the ÎŽ13C value of PC in the sediments is up 6â° higher than the 613C value of TOC. There is a larger difference when TOC abundances in the sediments are lowest. This suggests a significant component of C,-derived PC is present in the sediments, even when the proportion of C, biomass in the catchment is relatively low. This in turn, provides evidence for the preferential combustion and transport of C4-derived PC in tropical savannas. Savanna fires preferentially burn the grass understorey rather than large trees, leading to a bias toward the finer C,-derived PC being exported from a fire and accumulated in the sedimentary record while large particles of Crderived PC are more likely to remain at the site of burning. Our preliminary data suggest that application of HyPy in environmental studies enables accurate quantification of an essential component of the terrestrial C cycle. Moreover, the use of HyPy also enables the reliable determination of the stable carbon isotope composition of PC, which will enable deeper understanding of the dynamic role of biomass burning in the global carbon cycle
Screening for obstructive sleep apnea on the internet: randomized trial.
BACKGROUND: Obstructive sleep apnea is underdiagnosed. We conducted a pilot randomized controlled trial of an online intervention to promote obstructive sleep apnea screening among members of an Internet weight-loss community.
METHODS: Members of an Internet weight-loss community who have never been diagnosed with obstructive sleep apnea or discussed the condition with their healthcare provider were randomized to intervention (online risk assessment+feedback) or control. The primary outcome was discussing obstructive sleep apnea with a healthcare provider at 12 weeks.
RESULTS: Of 4700 members who were sent e-mail study announcements, 168 (97% were female, age 39.5 years [standard deviation 11.7], body mass index 30.3 [standard deviation 7.8]) were randomized to intervention (n=84) or control (n=84). Of 82 intervention subjects who completed the risk assessment, 50 (61%) were low risk and 32 (39%) were high risk for obstructive sleep apnea. Intervention subjects were more likely than control subjects to discuss obstructive sleep apnea with their healthcare provider within 12 weeks (11% [9/84] vs 2% [2/84]; P=.02; relative risk=4.50; 95% confidence interval, 1.002-20.21). The number needed to treat was 12. High-risk intervention subjects were more likely than control subjects to discuss obstructive sleep apnea with their healthcare provider (19% [6/32] vs 2% [2/84]; P=.004; relative risk=7.88; 95% confidence interval, 1.68-37.02). One high-risk intervention subject started treatment for obstructive sleep apnea.
CONCLUSION: An online screening intervention is feasible and likely effective in encouraging members of an Internet weight-loss community to discuss obstructive sleep apnea with their healthcare provider
Where the wild things are! Do urban green spaces with greater avian biodiversity promote more positive emotions in humans?
Urban green space can help mitigate the negative impacts of urban living and provide positive effects on citizensâ mood, health and well-being. Questions remain, however, as to whether all types of green space are equally beneficial, and if not, what landscape forms or key features optimise the desired benefits. For example, it has been cited that urban landscapes rich in wildlife (high biodiversity) may promote more positive emotions and enhance well-being. This research utilised a mobile phone App, employed to assess peopleâs emotions when they entered any one of 945 green spaces within the city of Sheffield, UK. Emotional responses were correlated to key traits of the individual green spaces, including levels of biodiversity the participant perceived around them. For a subsample of these green spaces, actual levels of biodiversity were assessed through avian and habitat surveys. Results demonstrated strong correlations between levels of avian biodiversity within a green space and human emotional response to that space. Respondents reported being happier in sites with greater avian biodiversity (pâ<â0.01, râ=â0.78) and a greater variety of habitats (pâ<â0.02, râ=â0.72). Relationships were strengthened when emotions were linked to perceptions of overall biodiversity (pâ<â0.001, râ=â0.89). So, when participants thought the site was wildlife rich, they reported more positive emotions, even when actual avian biodiversity levels were not necessarily enhanced. The data strengthens the arguments that nature enhances well-being through positive affect, and that increased âengagement with natureâ may help support human health within urban environments. The results have strong implications for city planning with respect to the design, management and use of city green spaces
JRA3 Electromagnetic Calorimeter Technical Design Report
This report describes the design of the prototype for an Silicon Tungsten electromagnetic calorimeter with unprecedented high granularity to be operated in a detector at the International Linear Collider (ILC). The R&D for the prototype is co-funded by the European Union in the FP6 framework within the so called EUDET project in the years 2006-2010. The dimensions of the prototype are similar to those envisaged for the final detector. Already at this stage the prototype features a highly compact design. The sensitive layers, the Very Front End Electronics serving 64 channels per ASIC and copper plates for heat draining are integrated within 2000 ÎŒm
Development of a modular and scalable data acquisition system for calorimeters at a linear collider
A data acquisition (DAQ) system has been developed which will read out and
control calorimeters serving as prototype systems for a future detector at an
electron-positron linear collider. This is a modular, flexible and scalable DAQ
system in which the hardware and signals are standards-based, using FPGAs and
serial links. The idea of a backplaneless system was also pursued with a
commercial development board housed in a PC and a chain of concentrator cards
between it and the detector forming the basis of the system. As well as
describing the concept and performance of the system, its merits and
disadvantages are discussed.Comment: 12 pages, 6 figures, accepted by JINST. Version updated accounting
for comments from journal referee
Synthesis of Knowledge of Extreme Fire Behavior: Volume 2 for Fire Behavior Specialists, Researchers
The National Wildfire Coordinating Groupâs definition of extreme fire behavior indicates a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning/spotting, presence of fire whirls, and strong convection column. Predictability is difficult as such fires often influence their environment to some degree and behave erratically, sometimes dangerously. Alternate terms include âblow upâ and âfire storm.â Fire managers examining fires over the last 100 years have come to understand many of the factors necessary for extreme fire behavior development. This effort produced guidelines included in current firefighter training, which presents the current methods of predicting extreme fire behavior by using the crown fire model, which is based on the environmental influences of weather, fuels, and topography.
Current training does not include the full extent of scientific understanding nor does it include the most recent scientific knowledge. National Fire Plan funds and the Joint Fire Science Program have sponsored newer research related to wind profilesâ influence on fire behavior, plume growth, crown fires, fire dynamics in live fuels, and conditions associated with vortex development. Of significant concern is that characteristic features of extreme fire behavior depend on conditions undetectable on the ground, namely invisible properties such as wind shear or atmospheric stability.
No one completely understands all the factors contributing to extreme fire behavior because of gaps in our knowledge. These gaps, as well as the limitations as to when various models or indices apply should be noted to avoid application where they are not appropriate or warranted. This synthesis summarizes existing extreme fire behavior knowledge. It consists of two volumes. Volume 1 is for fire managers, firefighters, and others in the fire community who are not experts or specialists in fire behavior but need to understand the basics of extreme fire behavior. Volume 2 is more technical and is intended for fire behaviorists and fire researchers
Infrastructure for Detector Research and Development towards the International Linear Collider
The EUDET-project was launched to create an infrastructure for developing and
testing new and advanced detector technologies to be used at a future linear
collider. The aim was to make possible experimentation and analysis of data for
institutes, which otherwise could not be realized due to lack of resources. The
infrastructure comprised an analysis and software network, and instrumentation
infrastructures for tracking detectors as well as for calorimetry.Comment: 54 pages, 48 picture
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