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A novel multi-task learning technique for offline handwritten short answer spotting and recognition
No full textOff-line examination is still being used in many parts of the world as it is a more economical way of conducting exams when compared to computer-based ones. Automatically and accurately assessing these handwritten exam papers poses a complex challenge, as high accuracy rates as possible are always desirable. Factors such as the attributes of the handwritten images, the presence of numerous classes, challenges related to word boundaries in languages such as Arabic, and the significant intra-class variation in handwritten forms contribute to the enduring complexity of word recognition and word spotting tasks. In order to address the problems, this research proposed a novel joint learning technique for word spotting and word recognition in a multi-task learning setting. A multi-task convolution neural network was employed to materialise the proposed concept. The word spotting task was dealt as a regression task and the other task was word recognition. The typical Faster-RCNN backbone was employed with the Region of Interest (RoI) pooling layer, which was then followed by two consecutive fully connected layers for the word spotting and recognition task. The experimental results are encouraging and demonstrate that the proposed research achieved a significant enhancement in the accuracy of short-answer assessment systems. As a result, the proposed technique can be implemented in short-answer assessment systems to improve both their efficiency and accuracy
A study of topology of the flip Stiefel manifolds
No full textA well known quotient of the real Stiefel manifold is the projective Stiefel manifold. We introduce a new family of quotients of the real Stiefel manifold by cyclic group of order 2 whose action is induced by simultaneous pairwise flipping of the coordinates. We obtain a description for their tangent bundles, compute their mod 2 cohomology and compute the Stiefel Whitney classes of these manifolds. We use these to provide applications to their stable span, parallelizability and equivariant maps, and some associated results in topological combinatorics
A worst-case optimal algorithm to compute the Minkowski sum of convex polytopes
No full textWe propose algorithms to compute the Minkowski sum of two or more convex polytopes represented by their face lattices in Rd. The time and space complexities of the pair-wise algorithm are O(dωnm) and O(n+m+M), respectively, where n, m and M are the face lattice sizes of the two summands and the sum, respectively, and ω≈2.37, currently, is the matrix multiplication exponent. We also show that this algorithm is worst-case optimal for fixed d. Next, we generalize the pair-wise algorithm to r\u3e2 convex polytopes in Rd. The time and space complexities of the r-summands generalized algorithm are O(dωmin{MN,r+∏i=1rNi}) and O(M+N), respectively, where Ni, 1≤i≤r, is the size of ith summand, N=∑i=1rNi is the total input size and M is the output size of the Minkowski sum. We show that the r-summands generalized algorithm is worst-case optimal for fixed d≥3 and
Age- and Gender-Specific Prevalence of Intellectually Disabled Population in India
No full textIntellectual disability in India is substantially under-reported, especially amongst females. This study quantifies the prevalence and gender bias in household reporting of intellectual disability by estimating the age-and-gender specific prevalence of the intellectually disabled by education, Socio-Demographic Index (SDI) score, place of residence, (rural/urban) and income of household head. We estimated prevalence (per 100,000) at 179 (95% CI: 173 to 185) for males and 120 (95% CI: 115 to 125) for females. Gender differences declined sharply with increased education, was higher for lower ages and low income and varied little by state development. Under-identification and under-reporting due to stigma are two plausible reasons for the gender differences in prevalence that increase with age
An application of counting ideals in ray classes
No full textWe prove a fully explicit generalized Brun–Titchmarsh theorem for an imaginary quadratic field K. More precisely, for any finite family of linearly independent linear forms with coefficients in [Formula presented], we count the number of integers at which all these linear forms take prime values in [Formula presented]
Azuma-Hoeffding bounds for a class of urn models
No full textWe obtain Azuma-Hoeffding bounds, which are exponentially decreasing, for the probabilities of being away from the limit for a class of urn models. The method consists of relating the variables to certain linear combinations using eigenvectors of the replacement matrix, thus bringing in appropriate martingales. Some cases of repeated eigenvalues are also considered using cyclic vectors. Moreover, strong convergence of proportions is proved as an application of these bounds
Channel-facilitated transport under resetting dynamics
No full textThe transport of particles through channels holds immense significance in physics, chemistry, and biological sciences. For instance, the motion of solutes through biological membranes is facilitated by specialized proteins that create water-filled channels. Valuable insights can be obtained by studying the transition paths of particles through a channel and gathering information on their lifetimes inside the channel as well as their exit probabilities. In a similar vein, we consider a one-dimensional model of channel-facilitated transport where a diffusive particle is subject to attractive interactions with the walls of the channel. We study the statistics of conditional and unconditional escape times in the presence of resetting—an intermittent dynamics that brings the particle back to its initial coordinate stochastically. We determine analytically the physical conditions under which such a resetting mechanism becomes beneficial for the faster escape of the particles from the channel, thus enhancing transport. Our theory has been verified with the aid of Brownian dynamics simulations for various interaction strengths and extents. The overall results presented herein highlight the scope of resetting-based strategies to be universally promising for complex transport processes of single or long molecules through biological membranes
CLUSTERING OF LARGE DEVIATIONS IN MOVING AVERAGE PROCESSES: THE SHORT MEMORY REGIME
No full textWe describe the cluster of large deviations events that arise when one such large deviations event occurs. We work in the framework of an infinite moving average process with a noise that has finite exponential moments
Comment on: Fürsich et al., 2023, Miocene instead of Jurassic: the importance of sound fieldwork for paleontological data analysis
No full textWe published a series of papers regarding the oldest turritellids, naticids, their paleoecological interaction, and gastropod biozonation, which are of Oxfordian in age, from the Jhura pond section, Kutch, western India. Recently, an Oxfordian age was challenged by Fürsich et al. (2023) and they argued for a Cenozoic age. The authors reproduced a local geological map based on regional data where the Jhura pond section sediments were overlying the Bhuj Formation. In the original regional data, there was no Bhuj Formation and the introduction of the Bhuj Formation served to show that Jhura pond section sediments were “allochthonous”. Other lines of argument against our conclusions (e.g., identification of associated bivalve fauna, foraminiferal assemblage, and geological context) were brought forward. There were additional inconsistencies, such as the reworking of Oxfordian fossils, in their comment/opinion pieces. The only hard evidence was the report of a microfaunal assemblage, but the taxa were identified at the generic level and most of the genera appear in the Jurassic or even earlier. Here we provide detailed and concrete evidence explaining features at the Jhura pond section, such as the subvertical nature of the beds, the ooid-bearing lithologies, the presence of various Oxfordian fossils, the difference in turritellids, naticid assemblages, and differences in the diversity curves between the present beds and the lower Miocene Chhasra Formation of Kutch. Detailed paleoecological analyses (both gastropods and bivalves) speak for two paleocommunities. We, therefore, reiterate that the present Jhura pond section sediments are Oxfordian in age and validate all the interpretations and conclusions that we have made in our previous papers
