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Efficient document-image super-resolution using convolutional neural network
No full textExperiments performed by us using optical character recognizers (OCRs) show that the character level accuracy of the OCR reduces significantly with decrease in the spatial resolution of document images. There are real life scenarios, where high-resolution (HR) images are not available, where it is desirable to enhance the resolution of the low-resolution (LR) document image. In this paper, our objective is to construct a HR image, given a single LR binary image. The works reported in the literature mostly deal with super-resolution of natural images, whereas we try to overcome the spatial resolution problem in document images. We have trained and obtained a novel convolutional model based on neural networks, which achieves significant improvement in terms of the peak-signal-to-noise ratio (PSNR) of the reconstructed HR images. Using parametric rectified linear units, mean PSNR improvements of 2.32, 4.38, 6.43 and 8.92 dB have been achieved over those of LR input images of 50, 75, 100 and 150 dots per inch (dpi) resolution and average word level accuracy of almost 43%, 45% and 57% on 75 dpi Tamil, English and Kannada images, respectively
A real-time implementation of SIFT using GPU
No full textScale-Invariant Feature Transform (SIFT) is one of the widely used interest point features. It has been successfully applied in various computer vision algorithms like object detection, object tracking, robotic mapping and large-scale image retrieval. Although SIFT descriptors are highly robust towards scale and rotation variations, the high computational complexity of the SIFT algorithm inhibits its use in applications demanding real-time response, and in algorithms dealing with very large-scale databases. This paper presents a parallel implementation of SIFT on a GPU, where we obtain a speed of around 55 fps for a 640 x 480 image. One of the main contributions of our work is the novel combined kernel optimization that has led to a significant improvement of 12.2 % in the execution speed. We compare our results with the existing SIFT implementations in the literature, and find that our implementation has better speedup than most of them
Solid-state diffusion-controlled growth of the phases in the Au-Sn system
No full textThe solid state diffusion-controlled growth of the phases is studied for the Au-Sn system in the range of room temperature to 200 degrees C using bulk and electroplated diffusion couples. The number of product phases in the interdiffusion zone decreases with the decrease in annealing temperature. These phases grow with significantly high rates even at the room temperature. The growth rate of the AuSn4 phase is observed to be higher in the case of electroplated diffusion couple because of the relatively small grains and hence high contribution of the grain boundary diffusion when compared to the bulk diffusion couple. The diffraction pattern analysis indicates the same equilibrium crystal structure of the phases in these two types of diffusion couples. The analysis in the AuSn4 phase relating the estimated tracer diffusion coefficients with grain size, crystal structure, the homologous temperature of experiments and the concept of the sublattice diffusion mechanism in the intermetallic compounds indicate that Au diffuses mainly via the grain boundaries, whereas Sn diffuses via both the grain boundaries and the lattice
Immunohistochemical evaluation of prime molecules in cervical lesions towards assessment of malignant potentiality
No full textObjective: A comparative immunohistochemical evaluation of p63, CD105, and E-cadherin expression pattern in histopathologically confirmed normal cervical epithelium (NCM), dysplastic cervical epithelium (DYS) and squamous cell carcinoma (SCC) of uterine cervix towards assessing malignant potentiality of the precancerous condition. Materials and Methods: The biopsies from cervical mucosa (normal, dysplasia, and cancer) were studied by routine hematoxylin and eosin (H and E) and by immunohistochemistry for p63, E-cadherin, and CD105 expression. The expressions of these molecules were assessed in a semiquantitative way by (i) counting p63 cell population and distribution, (ii) intensity scoring of E-cadherin along the expression path, and (iii) measuring CD105 expression density. Result: p63+ cells were highest in carcinomas followed by dysplasia and normal. An abrupt increase in CD105 expression was observed through change of normal to dysplasia and cancer. A decrease in membranous E-cadherin expression was noticed in the transformation from normal to precancer and cancers. Conclusion: The malignant potential of the dysplastic conditions is likely to be correlated with upregulation in p63 and CD105 expression and a simultaneous downregulation of membranous E-cadherin
Friendship across species borders: factors that facilitate and constrain heterospecific sociality
No full textOur understanding of animal sociality is based almost entirely on singlespecies sociality. Heterospecific sociality, although documented in numerous taxa and contexts, remains at the margins of sociality research and is rarely investigated in conjunction with single-species sociality. This could be because heterospecific and single-species sociality are thought to be based on fundamentally different mechanisms. However, our literature survey shows that heterospecific sociality based on mechanisms similar to single-species sociality is reported from many taxa, contexts and for various benefits. Therefore, we propose a conceptual framework to understand conspecific versus heterospecific social partner choice. Previous attempts, which are all in the context of social information, model partner choice as a trade-off between information benefit and competition cost, along a single phenotypic distance axis. Our framework of partner choice considers both direct grouping benefits and information benefits, allows heterospecific and conspecific partners to differ in degree and qualitatively, and uses a multi-dimensional trait space analysis of costs (competition and activity matching) and benefits (relevance of partner and quality of partner). We conclude that social partner choice is best-viewed as a continuum: some social benefits are obtainable only from conspecifics, some only from dissimilar heterospecifics, while many are potentially obtainable from conspecifics and heterospecifics
Bioelectricity from sugarcane bagasse co-generation in India-An assessment of resource potential, policies and market mobilization opportunities for the case of Uttar Pradesh
No full textStrong potential exists in India for bioelectricity (biomass-derived electricity) to meet the rising, domestic demand for energy. In order to fill the anticipated need, precise assessments of the resource potential are necessary as well as regularly-tracked resource inventories and apt policy. Studies addressing these aspects of energy management are limited for India, particularly in terms of energy planning at the local level. The current research evaluates the prospects for bagasse co-generation in Uttar Pradesh, the largest sugarcane-producing state in India. Specifically, the geo-spatial pattern of bagasse harvestable distributions and bioelectricity potential are assessed, along with policies and market mobilization directions for optimizing increased adoption of biomass energy. Results show that Uttar Pradesh has the potential to produce 27.05 million tonnes of usable bagasse annually. Major, sugarcane producing regions are identified within the western and north-eastern agro-climatic zones. Specific to power generation, the state could produce 1.93 GW of bioelectricity from sugarcane bagasse. At the agro-climatic zone level, the bioelectricity potential varies between 2.46 MW (Vindhyan zone) and 655 MW (western plain zone). When considered at the district level, the potential varies from 66 kW in Firozabad to an upper bound of 232 MW in Muzaffarnagar. The latter estimate indicates that some districts of Uttar Pradesh could be transitioned to 100% renewable electricity from bagasse co-generation. In conjunction with the ongoing growth path for India and energy access considerations, we recommend more strategically-focused energy policies, including auctions, regular resource-mapping, and zoning that can catalyze biomass energy adoption, while mitigating the greenhouse gas footprint of India. (C) 2018 Elsevier Ltd. All rights reserved
An Analogue Neuromorphic Co-Processor That Utilizes Device Mismatch for Learning Applications
No full textAs the integrated circuit (IC) technology advances into smaller nanometre feature sizes, a fixed-error noise known as device mismatch is introduced owing to the dissimilarity between transistors, and this degrades the accuracy of analog circuits. In this paper, we present an analog co-processor that uses this fixed-pattern noise to its advantage to perform complex computation. This circuit is an extension of our previously published trainable analogue block (TAB) framework and uses multiple inputs that substantially increase functionality. We present measurement results of our two-input analogue co-processor built using a 130-nm process technology and show its learning capabilities for regression and classification tasks. We also show that the co-processor, comprised of 100 neurons, is a low-power system with a power dissipation of only 1.1 mu W. The IC fabrication process contributes to randomness and variability in ICs, and we show that random device mismatch is favorable for the learning capability of our system as it causes variability among the neuronal tuning curves. The low-power capability of our framework makes it suitable for use in various battery-powered applications ranging from biomedical to military as a front-end analog co-processor
Evolution of ferromagnetism in two-dimensional electron gas of LaTiO3/SrTiO3
No full textUnderstanding, creating, and manipulating spin polarization of two-dimensional electron gases at complex oxide interfaces present an experimental challenge. For example, despite almost a decade long research effort, the microscopic origin of ferromagnetism in LaAlO3/SrTiO3 heterojunctions is still an open question. Here, by using a prototypical two-dimensional electron gas (2DEG) which emerges at the interface between band insulator SrTiO3 and antiferromagnetic Mott insulator LaTiO3, the experiment reveals the evidence for magnetic phase separation in a hole-doped Ti d(1) t(2g) system, resulting in spin-polarized 2DEG. The details of electronic and magnetic properties of the 2DEG were investigated by temperature-dependent d.c. transport, angle-dependent X-ray photoemission spectroscopy, and temperature-dependent magnetoresistance. The observation of clear hysteresis in magnetotransport at low magnetic fields implies spin-polarization from magnetic islands in the hole rich LaTiO3 near the interface. These findings emphasize the role of magnetic instabilities in doped Mott insulators, thus providing another path for designing all-oxide structures relevant to spintronic applications. Published by AIP Publishing
Effect of notch acuity on the fracture behavior of AZ31 Mg alloy
No full textIn this work, the effect of notch acuity on fracture behavior of rolled AZ31 Mg alloy is investigated by conducting mode-I fracture experiments using four point bend specimens with different notch root radii. Digital Image Correlation (DIC) technique is employed to determine the angle of rotation of the specimen and the fracture toughness is obtained from moment versus rotation curves. It is found that the fracture toughness J(c) increases linearly with notch root radius beyond a threshold value and is almost constant below this limit. This trend is rationalized from fractographic observations near the crack initiation region which show predominantly quasi-brittle features for fatigue pre-cracked specimen and dimples of increasing size in notched specimens with enhancement in notch root radius. Significant tensile twinning is noticed in the ligament for all specimens, especially near their far edge. This is found to impart substantial toughening even in the fatigue pre-cracked specimen which fails by a locally quasi-brittle mechanism. Finally, the strong increase in J(c) with notch root radius beyond a threshold is interpreted using two ductile fracture initiation models. (C) 2017 Elsevier Ltd. All rights reserved
Ionic liquid-assisted hydrothermal synthesis of SnS nanoparticles: Electrode materials for lithium batteries, photoluminescence and photocatalytic activities
No full textTin mono-sulphide (SnS) nanoparticles (Nps) have been successfully synthesised through ionic liquid assisted hydrothermal method using hydrated tin (II) chloride as a precursor, thiourea as sulphur source precursors using 2-Methoxy ethyl methyl imidazolium methane sulfonate ionic liquid as co-solvent. The Reitveld refinement on powder X-ray diffraction (PXRD) confirmed the presence of orthorhombic SnS structure as major phase along with traces amount of SnS 2 and Sn2S3. Diffuse reflectance spectrum studies revealed the energy band gap around 1.38 eV. TEM images confirmed the SnS Nps with average particle size of 40 nm and HRTEM suggest good crystallinity. The electrochemical property for lithium storage behaviour shows an initial discharge capacity of 658 mAh/g and it retains discharge capacity of 426 mAh/g for 16 cycles, at current density 100 mA/g. The obtained results indicate that SnS Nps to be one of the possible promising anode materials for next generation Lithium batteries. Photoluminescence study of SnS Nps shows a strong green emission at 530 nm. SnS Nps were also tested for the photocatalytic adsorption of methylene blue and Rhodamine B. (C) 2017 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved