885 research outputs found
Real-Time, Multiple Pan/Tilt/Zoom Computer Vision Tracking and 3D Positioning System for Unmanned Aerial System Metrology
The study of structural characteristics of Unmanned Aerial Systems (UASs) continues to be an important field of research for developing state of the art nano/micro systems. Development of a metrology system using computer vision (CV) tracking and 3D point extraction would provide an avenue for making these theoretical developments. This work provides a portable, scalable system capable of real-time tracking, zooming, and 3D position estimation of a UAS using multiple cameras. Current state-of-the-art photogrammetry systems use retro-reflective markers or single point lasers to obtain object poses and/or positions over time. Using a CV pan/tilt/zoom (PTZ) system has the potential to circumvent their limitations. The system developed in this paper exploits parallel-processing and the GPU for CV-tracking, using optical flow and known camera motion, in order to capture a moving object using two PTU cameras. The parallel-processing technique developed in this work is versatile, allowing the ability to test other CV methods with a PTZ system using known camera motion. Utilizing known camera poses, the object\u27s 3D position is estimated and focal lengths are estimated for filling the image to a desired amount. This system is tested against truth data obtained using an industrial system
Optical Flow Background Estimation for Real-time Pan/tilt Camera Object Tracking
As Computer Vision (CV) techniques develop, pan/tilt camera systems are able to enhance data capture capabilities over static camera systems. In order for these systems to be effective for metrology purposes, they will need to respond to the test article in real-time with a minimum of additional uncertainty. A methodology is presented here for obtaining high-resolution, high frame-rate images, of objects traveling at speeds ⩾1.2 m/s at 1 m from the camera by tracking the moving texture of an object. Strong corners are determined and used as flow points using implementations on a graphic processing unit (GPU), resulting in significant speed-up over central processing units (CPU). Based on directed pan/tilt motion, a pixel-to-pixel relationship is used to estimate whether optical flow points fit background motion, dynamic motion or noise. To smooth variation, a two-dimensional position and velocity vector is used with a Kalman filter to predict the next required position of the camera so the object stays centered in the image. High resolution images can be stored by a parallel process resulting in a high frame rate procession of images for post-processing. The results provide real-time tracking on a portable system using a pan/tilt unit for generic moving targets where no training is required and camera motion is observed from high accuracy encoders opposed to image correlation
Massively parallel sequencing of customised forensically informative SNP panels on the MiSeq.
Forensic DNA-based intelligence, or forensic DNA phenotyping, utilises SNPs to infer the biogeographical ancestry and externally visible characteristics of the donor of evidential material. SNaPshot® is a commonly employed forensic SNP genotyping technique, which is limited to multiplexes of 30-40 SNPs in a single reaction and prone to PCR contamination. Massively parallel sequencing has the ability to genotype hundreds of SNPs in multiple samples simultaneously by employing an oligonucleotide sample barcoding strategy. This study of the Illumina MiSeq massively parallel sequencing platform analysed 136 unique SNPs in 48 samples from SNaPshot PCR amplicons generated by five established forensic DNA phenotyping assays comprising the SNPforID 52-plex, SNPforID 34-plex, Eurasiaplex, Pacifiplex and IrisPlex. Approximately 3 GB of sequence data were generated from two MiSeq flow cells and profiles were obtained from just 0.25 ng of DNA. Compared with SNaPshot, an average 98% genotyping concordance was achieved. Our customised approach was successful in attaining SNP profiles from extremely degraded, inhibited, and compromised casework samples. Heterozygote imbalance and sequence coverage in negative controls highlight the need to establish baseline sequence coverage thresholds and refine allele frequency thresholds. This study demonstrates the potential of the MiSeq for forensic SNP analysis
CDC5 Inhibits the Hyperphosphorylation of the Checkpoint Kinase Rad53, Leading to Checkpoint Adaptation
The mechanistic role of the yeast kinase CDC5, in allowing cells to adapt to the presence of irreparable DNA damage and continue to divide, is revealed
The Impact of an Intense Cyclone on Short-Term Sea Ice Loss in a Fully Coupled Atmosphere-Ocean-Ice Model
AbstractArctic cyclones may be associated with periods of locally enhanced sea ice loss during the summer, and some studies have found that an intense cyclone in August 2012 resulted in a rapid sea ice retreat. This study uses a coupled atmosphere‐ocean‐ice model (Navy‐ESPC) to explore the relationship between the 2012 cyclone and short‐term sea ice melting. There are two mechanisms of cyclone‐induced melting in Navy‐ESPC: turbulent mixing of a warm layer located at 15‐ to 35‐m depth increases bottom melting and warm air advection by the strong surface winds increases surface melting. Although the rate of sea ice melt is substantially increased in association with the cyclone, this effect is confined to a relatively small region and only lasts for a few days. There is no clear signature of the cyclone on the overall Arctic sea ice extent in Navy‐ESPC
Health-related quality of life among adolescents with eating disorders
Objective
Health-related quality of life (HRQoL) is an emerging area of research in eating disorders (EDs) that has not been examined in adolescents in detail. The aim of the current study is to investigate HRQoL in an adolescent ED sample, examining the impact of ED symptoms on HRQoL.
Methods
Sixty-seven treatment-seeking adolescents (57 females) with anorexia nervosa (AN), bulimia nervosa (BN), or eating disorder not otherwise specified (EDNOS) completed self-report measures of HRQoL and ED symptoms.
Results
Participants reported poorer HRQoL in mental health domains than in physical health domains. Disordered attitudes, binge eating, and compensatory behaviors were associated with poorer mental health HRQoL, and body dissatisfaction was associated with poorer physical health HRQoL.
Conclusion
The current study assessed HRQoL among adolescents with EDs, finding several consistencies with the literature on adults with EDs. Future research should compare adolescents and adults with EDs on HRQoL
The metastable Q state of ThO: A new resource for the ACME electron EDM search
The best upper limit for the electron electric dipole moment was recently set
by the ACME collaboration. This experiment measures an electron spin-precession
in a cold beam of ThO molecules in their metastable state.
Improvement in the statistical and systematic uncertainties is possible with
more efficient use of molecules from the source and better magnetometry in the
experiment, respectively. Here, we report measurements of several relevant
properties of the long-lived state of ThO, and show that this
state is a very useful resource for both these purposes. The state lifetime
is long enough that its decay during the time of flight in the ACME beam
experiment is negligible. The large electric dipole moment measured for the
state, giving rise to a large linear Stark shift, is ideal for an electrostatic
lens that increases the fraction of molecules detected downstream. The measured
magnetic moment of the state is also large enough to be used as a sensitive
co-magnetometer in ACME. Finally, we show that the state has a large
transition dipole moment to the state, which allows for efficient
population transfer between the ground state and the state
via Stimulated Raman Adiabatic Passage (STIRAP). We demonstrate %
STIRAP transfer efficiency. In the course of these measurements, we also
determine the magnetic moment of state, the transition
dipole moment, and branching ratios of decays from the state.Comment: 21 pages, 6 figures, 5 pages appendice
- …