2,470 research outputs found
Ethyl 4-(dimethylamino)benzoate
Molecules of the title compound, C11H15NO2, are essentially planar (r.m.s. deviation = 0.035 Å) and are linked into a chain along the a axis by weak C—H⋯O hydrogen bonds
Foreground algorithms for detection and extraction of an object in multimedia
Background Subtraction of a foreground object in multimedia is one of the major preprocessing steps involved in many vision-based applications. The main logic for detecting moving objects from the video is difference of the current frame and a reference frame which is called “background image” and this method is known as frame differencing method. Background Subtraction is widely used for real-time motion gesture recognition to be used in gesture enabled items like vehicles or automated gadgets. It is also used in content-based video coding, traffic monitoring, object tracking, digital forensics and human-computer interaction. Now-a-days due to advent in technology it is noticed that most of the conferences, meetings and interviews are done on video calls. It’s quite obvious that a conference room like atmosphere is not always readily available at any point of time. To eradicate this issue, an efficient algorithm for foreground extraction in a multimedia on video calls is very much needed. This paper is not to just build Background Subtraction application for Mobile Platform but to optimize the existing OpenCV algorithm to work on limited resources on mobile platform without reducing the performance. In this paper, comparison of various foreground detection, extraction and feature detection algorithms are done on mobile platform using OpenCV. The set of experiments were conducted to appraise the efficiency of each algorithm over the other. The overall performances of these algorithms were compared on the basis of execution time, resolution and resources required
Diffusion and mixing in gravity-driven dense granular flows
We study the transport properties of particles draining from a silo using
imaging and direct particle tracking. The particle displacements show a
universal transition from super-diffusion to normal diffusion, as a function of
the distance fallen, independent of the flow speed. In the super-diffusive (but
sub-ballistic) regime, which occurs before a particle falls through its
diameter, the displacements have fat-tailed and anisotropic distributions. In
the diffusive regime, we observe very slow cage breaking and Peclet numbers of
order 100, contrary to the only previous microscopic model (based on diffusing
voids). Overall, our experiments show that diffusion and mixing are dominated
by geometry, consistent with fluctuating contact networks but not thermal
collisions, as in normal fluids
SCUBA observations of the host galaxies of four dark gamma-ray bursts
We present the results of a search for submillimetre-luminous host galaxies
of optically dark gamma-ray bursts (GRBs) using the Submillimetre Common-User
Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). We made
photometry measurements of the 850-micron flux at the location of four `dark
bursts', which are those with no detected optical afterglow despite rapid deep
searches, and which may therefore be within galaxies containing substantial
amounts of dust. We were unable to detect any individual source significantly.
Our results are consistent with predictions for the host galaxy population as a
whole, rather than for a subset of dusty hosts. This indicates that optically
dark GRBs are not especially associated with very submillimetre-luminous
galaxies and so cannot be used as reliable indicators of dust-enshrouded
massive star-formation activity. Further observations are required to establish
the relationship between the wider GRB host galaxy population and SCUBA
galaxies.Comment: 6 pages. Accepted for publication in MNRA
1,1′-[4-(2,4-Dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-diyl]diethanone
In the title compound, C17H17Cl2NO2, the central 1,4-dihydropyridine ring adopts a flattened-boat conformation. The ethanone substituents of the dihydropyridine ring at positions 3 and 5 have synperiplanar (cis) or antiperiplanar (trans) conformations with respect to the adjacent C=C bonds in the dihydropyridine ring. The 2,4-dichlorophenyl ring is almost planar [r.m.s. deviation = 0.0045 (1) Å] and almost perpendicular [89.27 (3)°] to the mean plane of the dihydropyridine ring. In the crystal, an N—H⋯O hydrogen bond links molecules into a zigzag chain along the ac diagonal. C—H⋯Cl contacts form centrosymmetric dimers and additional weak C—H⋯O contacts further consolidate the packing
Precise measurements of UV atomic lines: Hyperfine structure and isotope shifts in the 398.8 nm line of Yb
We demonstrate a technique for frequency measurements of UV transitions with
sub-MHz precision. The frequency is measured using a ring-cavity resonator
whose length is calibrated against a reference laser locked to the line
of Rb. We have used this to measure the 398.8 nm line of atomic Yb. We report isotope shifts of all the
seven stable isotopes, including the rarest isotope Yb. We have been
able to resolve the overlapping Yb() and Yb
transitions for the first time. We also obtain high-precision measurements of
excited-state hyperfine structure in the odd isotopes, Yb and
Yb. The measurements resolve several discrepancies among earlier
measurements.Comment: 7 pages, 6 figure
2,4,6,8-Tetrakis(4-fluorophenyl)-3,7-diazabicyclo[3.3.1]nonan-9-one
In the title compound, C31H24F4N2O, the bicyclo[3.3.1]nonane ring exists in a chair-boat conformation. Two of the four fluorine-substituted rings adopt equatorial dispositions with the piperidin-4-one rings. Molecules are linked into a two-dimensional network parallel to (01) by N—H⋯O, C—H⋯F and C—H⋯O hydrogen bonds. Intermolecular N—H⋯π and C—H⋯π interactions are also observed
4-Azido-2-chloro-6-methylquinoline
In the title compound, C10H7ClN4, the quinoline ring system is planar [maximum deviation 0.0035 (10) Å]. The crystal structure is stabilized by van der Waals and π–π stacking interactions [centroid–centroid distance 3.6456 (17) Å]
l-Asparagine–l-tartaric acid (1/1)
In the title compound, C4H8N2O3·C4H6O6, the amino acid molecule exists as a zwitterion and the carboxylic acid in an un-ionized state. The tartaric acid molecules are linked into layers parallel to the ab plane by O—H⋯O hydrogen bonds. The amino acid molecules are also linked into layers parallel to the ab plane by N—H⋯O and C—H⋯O hydrogen bonds. The alternating tartaric acid and amino acid layers are linked into a three-dimensional framework by N—H⋯O and O—H⋯O hydrogen bonds
Long-Term Neurobehavioral and Quality of Life Outcomes of Critically Ill Children after Glycemic Control
© 2019 Elsevier Inc. Objectives: To investigate adaptive skills, behavior, and quality health-related quality of life in children from 32 centers enrolling in the Heart And Lung Failure-Pediatric INsulin Titration randomized controlled trial. Study design: This prospective longitudinal cohort study compared the effect of 2 tight glycemic control ranges (lower target, 80-100 mg/dL vs higher target, 150-180 mg/dL) 1-year neurobehavioral and health-related quality of life outcomes. Subjects had confirmed hyperglycemia and cardiac and/or respiratory failure. Patients aged 2-16 years old enrolled between April 2012 and September 2016 were studied at 1 year after intensive care discharge. The primary outcome, adaptive skills, was assessed using the Vineland Adaptive Behavior Scale. Behavior and health-related quality of life outcomes were assessed as secondary outcomes using the Pediatric Quality of Life and Child Behavior Checklist at baseline and 1-year follow-up. Group differences were evaluated using regression models adjusting for age category, baseline overall performance, and risk of mortality. Results: Of 369 eligible children, 358 survived after hospital discharge and 214 (60%) completed follow-up. One-year Vineland Adaptive Behavior Scale-II composite scores were not different (mean ± SD, 79.9 ± 25.5 vs 79.4 ± 26.9, lower vs higher target; P =.20). Improvement in Pediatric Quality of Life total health from baseline was greater in the higher target group (adjusted mean difference, 8.2; 95% CI, 1.1-15.3; P =.02). Conclusions: One-year adaptive behavior in critically ill children with lower vs higher target glycemic control did not differ. The higher target group demonstrated improvement from baseline in overall health. This study affirms the lack of benefit of lower glucose targeting. Trial registration: ClinicalTrials.gov: NCT01565941
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