702 research outputs found
Clustering, Chaos and Crisis in a Bailout Embedding Map
We study the dynamics of inertial particles in two dimensional incompressible
flows. The particle dynamics is modelled by four dimensional dissipative
bailout embedding maps of the base flow which is represented by 2-d area
preserving maps. The phase diagram of the embedded map is rich and interesting
both in the aerosol regime, where the density of the particle is larger than
that of the base flow, as well as the bubble regime, where the particle density
is less than that of the base flow. The embedding map shows three types of
dynamic behaviour, periodic orbits, chaotic structures and mixed regions. Thus,
the embedding map can target periodic orbits as well as chaotic structures in
both the aerosol and bubble regimes at certain values of the dissipation
parameter. The bifurcation diagram of the 4-d map is useful for the
identification of regimes where such structures can be found. An attractor
merging and widening crisis is seen for a special region for the aerosols. At
the crisis, two period-10 attractors merge and widen simultaneously into a
single chaotic attractor. Crisis induced intermittency is seen at some points
in the phase diagram. The characteristic times before bursts at the crisis show
power law behaviour as functions of the dissipation parameter. Although the
bifurcation diagram for the bubbles looks similar to that of aerosols, no such
crisis regime is seen for the bubbles. Our results can have implications for
the dynamics of impurities in diverse application contexts.Comment: 16 pages, 9 figures, submitted for publicatio
Structured Light-Based 3D Reconstruction System for Plants.
Camera-based 3D reconstruction of physical objects is one of the most popular computer vision trends in recent years. Many systems have been built to model different real-world subjects, but there is lack of a completely robust system for plants. This paper presents a full 3D reconstruction system that incorporates both hardware structures (including the proposed structured light system to enhance textures on object surfaces) and software algorithms (including the proposed 3D point cloud registration and plant feature measurement). This paper demonstrates the ability to produce 3D models of whole plants created from multiple pairs of stereo images taken at different viewing angles, without the need to destructively cut away any parts of a plant. The ability to accurately predict phenotyping features, such as the number of leaves, plant height, leaf size and internode distances, is also demonstrated. Experimental results show that, for plants having a range of leaf sizes and a distance between leaves appropriate for the hardware design, the algorithms successfully predict phenotyping features in the target crops, with a recall of 0.97 and a precision of 0.89 for leaf detection and less than a 13-mm error for plant size, leaf size and internode distance
An Efficient QBIR System Using Adaptive Segmentation and Multiple Features
AbstractQuery by Image Content Retrieval abbreviated as QBIR, has become new thirst now a days. By using this systems, user can retrieve the similar images of an already existed image (or) a rough sketch (or) a symbolic representation. To make more efficient and user friendly QBIR multiple features areemployed. This paper proposes a novel approach for image retrieval using adaptive k-means clustering and shape, texture features. The experimental results portraystheperformance of the proposed retrieval system in terms of better precision. To evaluate the proposed method COIL and MPEG-7 shape 1 datasets are used
Transport and diffusion in the embedding map
We study the transport properties of passive inertial particles in a
incompressible flows. Here the particle dynamics is represented by the
dissipative embedding map of area-preserving standard map which models
the incompressible flow. The system is a model for impurity dynamics in a fluid
and is characterized by two parameters, the inertia parameter , and the
dissipation parameter . We obtain the statistical characterisers of
transport for this system in these dynamical regimes. These are, the recurrence
time statistics, the diffusion constant, and the distribution of jump lengths.
The recurrence time distribution shows a power law tail in the dynamical
regimes where there is preferential concentration of particles in sticky
regions of the phase space, and an exponential decay in mixing regimes. The
diffusion constant shows behaviour of three types - normal, subdiffusive and
superdiffusive, depending on the parameter regimes. Phase diagrams of the
system are constructed to differentiate different types of diffusion behaviour,
as well as the behaviour of the absolute drift. We correlate the dynamical
regimes seen for the system at different parameter values with the transport
properties observed at these regimes, and in the behaviour of the transients.
This system also shows the existence of a crisis and unstable dimension
variability at certain parameter values. The signature of the unstable
dimension variability is seen in the statistical characterisers of transport.
We discuss the implications of our results for realistic systems.Comment: 28 pages, 14 figures, To Appear in Phys. Rev. E; Vol. 79 (2009
Prediction of preterm labour by cervical length
Background: Preterm birth is one of the commonest causes of perinatal mortality. Cervical length is one of the major determinants of preterm delivery.Methods: This prospective observational study of 100 pregnant women attending ANC OPD was carried out at D.Y. Patil Hospital, Kolhapur. The pregnant women were scanned for cervical length between 11-14 weeks and 20-22 weeks of gestation, using USG machine with TVS probe (mindray DC-7).Results: The mean value of cervical length in pregnant women at 11-14 weeks was 3.94 cm and at 20-22 weeks of gestation it was 3.38 cm. There was shortening in the pregnant cervix from first to second trimester. In the study 12% of patients delivered prematurely who had reduction in cervical length from first trimester to second trimester. The inverse relation between the cervical length during pregnancy and frequency of preterm delivery was confirmed. The decrease in cervical length at 11-14 weeks of gestation and 20-22 weeks of gestation was useful for identifying patients at increased risk for pre-trerm.Conclusions: Our findings confirm those of previous studies that have found an inverse relation between the length of the cervix, as measured by transvaginal ultrasonography during pregnancy, and the frequency of preterm delivery. We found that the cervical length measured at 11-14 weeks and 20-22 weeks gestation was decreased in asymptomatic women with single to n pregnancies was useful for identifying patients at increased risk for preterm delivery
A High-Throughput Method for Illumina RNA-Seq Library Preparation.
With the introduction of cost effective, rapid, and superior quality next generation sequencing techniques, gene expression analysis has become viable for labs conducting small projects as well as large-scale gene expression analysis experiments. However, the available protocols for construction of RNA-sequencing (RNA-Seq) libraries are expensive and/or difficult to scale for high-throughput applications. Also, most protocols require isolated total RNA as a starting point. We provide a cost-effective RNA-Seq library synthesis protocol that is fast, starts with tissue, and is high-throughput from tissue to synthesized library. We have also designed and report a set of 96 unique barcodes for library adapters that are amenable to high-throughput sequencing by a large combination of multiplexing strategies. Our developed protocol has more power to detect differentially expressed genes when compared to the standard Illumina protocol, probably owing to less technical variation amongst replicates. We also address the problem of gene-length biases affecting differential gene expression calls and demonstrate that such biases can be efficiently minimized during mRNA isolation for library preparation
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