165 research outputs found
IoT Design Challenges and the Social IoT Solution
The IoT (Internet of Things) promises to be the major phenomenon in information technology in the near term. By some forecasts more than half of all new IT system deployments by 2020 will incorporate some form of IoT technology. Currently, however, there is no dominant IoT platform and no universal IoT design standards currently in use. This contributes to Architectural Heterogeneity which in turn contributes to high integration costs and inhibits IoT benefits realisation. The use of universal design standards presents one solution to this problem. Social Internet of Things (SIoT) methods use the way that people manage social relationships as a reference architecture for the way to manage the interaction between the various Things in an IoT network. This paper discusses some of the current IoT design challenges and presents solutions couched in SIoT that can be used as standards for future IoT designs to reduce Architectural Heterogeneity
Correlated X-ray/Ultraviolet/Optical Variability in NGC 6814
We present results of a 3-month combined X-ray/UV/optical monitoring campaign
of the Seyfert 1 galaxy NGC 6814. The object was monitored by Swift from June
through August 2012 in the X-ray and UV bands and by the Liverpool Telescope
from May through July 2012 in B and V. The light curves are variable and
significantly correlated between wavebands. Using cross-correlation analysis,
we compute the time lag between the X-ray and lower energy bands. These lags
are thought to be associated with the light travel time between the central
X-ray emitting region and areas further out on the accretion disc. The computed
lags support a thermal reprocessing scenario in which X-ray photons heat the
disc and are reprocessed into lower energy photons. Additionally, we fit the
lightcurves using CREAM, a Markov Chain Monte Carlo code for a standard disc.
The best-fitting standard disc model yields unreasonably high super-Eddington
accretion rates. Assuming more reasonable accretion rates would result in
significantly under-predicted lags. If the majority of the reprocessing
originates in the disc, then this implies the UV/optical emitting regions of
the accretion disc are farther out than predicted by the standard thin disc
model. Accounting for contributions from broad emission lines reduces the lags
in B and V by approximately 25% (less than the uncertainty in the lag
measurements), though additional contamination from the Balmer continuum may
also contribute to the larger than expected lags. This discrepancy between the
predicted and measured interband delays is now becoming common in AGN where
wavelength-dependent lags are measured.Comment: 11 pages, 8 figures, accepted for publication in MNRA
Water Law Be Dammed?: How Dam Construction by Non-hegemonic Basin States Places Strain on the Customary Law of Transboundary Watercourses
Methods for Detection and Identification of Pathogenic Bacteria
1. Identification of unique genomic sequences associated with low versus high cytotoxicity isolates of Clostridium piliforme.; 2. Develop an amplified fluorescent antigen displacement assay directed toward methicillin-resistant Staphylococcus aureus low affinity penicillin binding protein PBP2a.; 3. Develop a label-free multiplex assay for specific detection of enteric pathogens Salmonella Typhimurium and E. coli O157:H7 using optical microring resonators. 1. Markers specific for high cytotoxicity C. piliforme isolate were not identified. However, 16 possible and 1 confirmed C. piliforme-specific marker were identified.; 2. Amplified fluorescent peptide displacement assay component was developed, intended as part of a flow-through detection platform. Some detection of antigen (labeled peptide) was detected in assay when applied to Amplifying Fluorescent Polymer (AFP), but results were not strongly positive, possibly due to poor performing peptide antigen-derived antibody. 3. Label-free detection of whole bactVeterinary Pathobiolog
Investigation for improving Global Positioning System (GPS) orbits using a discrete sequential estimator and stochastic models of selected physical processes
GEODYNII is a conventional batch least-squares differential corrector computer program with deterministic models of the physical environment. Conventional algorithms were used to process differenced phase and pseudorange data to determine eight-day Global Positioning system (GPS) orbits with several meter accuracy. However, random physical processes drive the errors whose magnitudes prevent improving the GPS orbit accuracy. To improve the orbit accuracy, these random processes should be modeled stochastically. The conventional batch least-squares algorithm cannot accommodate stochastic models, only a stochastic estimation algorithm is suitable, such as a sequential filter/smoother. Also, GEODYNII cannot currently model the correlation among data values. Differenced pseudorange, and especially differenced phase, are precise data types that can be used to improve the GPS orbit precision. To overcome these limitations and improve the accuracy of GPS orbits computed using GEODYNII, we proposed to develop a sequential stochastic filter/smoother processor by using GEODYNII as a type of trajectory preprocessor. Our proposed processor is now completed. It contains a correlated double difference range processing capability, first order Gauss Markov models for the solar radiation pressure scale coefficient and y-bias acceleration, and a random walk model for the tropospheric refraction correction. The development approach was to interface the standard GEODYNII output files (measurement partials and variationals) with software modules containing the stochastic estimator, the stochastic models, and a double differenced phase range processing routine. Thus, no modifications to the original GEODYNII software were required. A schematic of the development is shown. The observational data are edited in the preprocessor and the data are passed to GEODYNII as one of its standard data types. A reference orbit is determined using GEODYNII as a batch least-squares processor and the GEODYNII measurement partial (FTN90) and variational (FTN80, V-matrix) files are generated. These two files along with a control statement file and a satellite identification and mass file are passed to the filter/smoother to estimate time-varying parameter states at each epoch, improved satellite initial elements, and improved estimates of constant parameters
Defining the Genetic Basis for Seed Yield in Arabidopsis thaliana
Seed number per fruit is a vitally important trait because it determines total agricultural yield. Despite its importance, the genes that direct seed yield remain relatively unknown. We are using Recombinant Inbred Lines (RILs) in the weedy plant Arabidopsis thaliana to explore the heritability of seed yield and genetically map the genes responsible. Up to eight fruits were collected per plant from each RIL. Seeds were scanned using a flatbed scanner and counted using Adobe Photoshop CS6. With this data, we performed an ANOVA to calculate heritability, the amount of variance in the seed yield trait due to genetics. The heritability of seed yield was found to be 23.24 percent. Using the same data set, we are currently performing composite interval mapping to identify the genomic regions that contain the genes that direct seed yield, an analysis we will report on. Locating the genomic regions that contain seed yield is the first vital step in defining the gene network that directs seed number in fruit
Reliability and validity of the transport and physical activity questionnaire (TPAQ) for assessing physical activity behaviour
No current validated survey instrument allows a comprehensive assessment of both physical activity and travel behaviours for use in interdisciplinary research on walking and cycling. This study reports on the test-retest reliability and validity of physical activity measures in the transport and physical activity questionnaire (TPAQ)
Reliability and validity of the transport and physical activity questionnaire (TPAQ) for assessing physical activity behaviour
Background: No current validated survey instrument allows a comprehensive assessment of both physical activity and
travel behaviours for use in interdisciplinary research on walking and cycling. This study reports on the test-retest reliability
and validity of physical activity measures in the transport and physical activity questionnaire (TPAQ).
Methods: The TPAQ assesses time spent in different domains of physical activity and using different modes of transport for
five journey purposes. Test-retest reliability of eight physical activity summary variables was assessed using intra-class
correlation coefficients (ICC) and Kappa scores for continuous and categorical variables respectively. In a separate study, the
validity of three survey-reported physical activity summary variables was assessed by computing Spearman correlation
coefficients using accelerometer-derived reference measures. The Bland-Altman technique was used to determine the
absolute validity of survey-reported time spent in moderate-to-vigorous physical activity (MVPA).
Results: In the reliability study, ICC for time spent in different domains of physical activity ranged from fair to substantial for
walking for transport (ICC = 0.59), cycling for transport (ICC = 0.61), walking for recreation (ICC = 0.48), cycling for recreation
(ICC = 0.35), moderate leisure-time physical activity (ICC = 0.47), vigorous leisure-time physical activity (ICC = 0.63), and total
physical activity (ICC = 0.56). The proportion of participants estimated to meet physical activity guidelines showed
acceptable reliability (k = 0.60). In the validity study, comparison of survey-reported and accelerometer-derived time spent in
physical activity showed strong agreement for vigorous physical activity (r = 0.72, p,0.001), fair but non-significant
agreement for moderate physical activity (r = 0.24, p = 0.09) and fair agreement for MVPA (r = 0.27, p = 0.05). Bland-Altman
analysis showed a mean overestimation of MVPA of 87.6 min/week (p = 0.02) (95% limits of agreement 2447.1 to
+622.3 min/week).
Conclusion: The TPAQ provides a more comprehensive assessment of physical activity and travel behaviours and may be
suitable for wider use. Its physical activity summary measures have comparable reliability and validity to those of similar
existing questionnaires
Improving Swift-XRT positions of GRBs
Since GRBs fade rapidly, it is important to publish accurate, precise
positions at early times. For Swift-detected bursts, the best promptly
available position is most commonly the X-ray Telescope (XRT) position. We
present two processes, developed by the Swift team at Leicester, which are now
routinely used to improve the precision and accuracy of the XRT positions
reported by the Swift team. Both methods, which are fully automated, make use
of a PSF-fitting approach which accounts for the bad columns on the CCD. The
first method yields positions with 90% error radii <4.4" 90% of the time,
within 10--20 minutes of the trigger. The second method astrometrically
corrects the position using UVOT field stars and the known mapping between the
XRT and UVOT detectors, yielding enhanced positions with 90% error radii of
<2.8" 90% of the time, usually ~2 hours after the trigger.Comment: 4 pages, to appear in the proceedings of "Gamma Ray Bursts 2007,
Santa Fe
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