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Bias-induced circular current in a loop nanojunction with AAH modulation: Role of hopping dimerization
No full textIn this work, we investigate the interplay between correlated disorder and hopping dimerization on bias-driven circular current in a loop conductor that is clamped between two electrodes. The correlated disorder is introduced in site energies of the ring in the form of Aubry-André-Harper (AAH) model. Simulating the quantum system within a tight-binding framework all the results are worked out based on the waveguide theory. Unlike transport current, circular current in the loop conductor can get enhanced with increasing disorder strength. This enhancement becomes much effective when hopping dimerization is included which is taken following the Su-Schrieffer-Heeger (SSH) model. The characteristic features of bias-driven circular current are studied under different input conditions and we find that the results are robust for a wide range of physical parameters. For the sake of completeness, uncorrelated disorder is also considered. Our analysis may provide a new insight in analyzing transport behavior in different disordered lattices in the presence of additional restrictions in hopping integrals
Burden of undernutrition among under-five Bengali children and its determinants: Findings from Demographic and Health Surveys of Bangladesh and India
No full textBackground Globally, undernutrition is the leading cause of mortality among under-five children. Bangladesh and India were in the top ten countries in the world for under-five mortality. The aim of the study was to investigate the nutritional status of Bengali under-five children. Methods Data on 25938 under-five children were retrieved from the Bangladesh Demographic and Health Survey 2017–18 (BDHS) and the National Family Health Survey of India 2015–16 (NFHS-4). Stunting, wasting, underweight and thinness were considered to understand the nutritional status of under-five children. Binary logistic regression was used to identify associated factors of undernutrition among children. Results Over one-quarter of Bengali under-five children were found to be suffering from the problem of stunting (31.9%) and underweight (28.1%), while other nutritional indicators raised serious concern and revealed inter-country disparities. In the cases of wasting, underweight and thinness, the mean z-scores and frequency differences between Bangladesh and India were significant. The nutritional status of Bengali under-five children appeared to have improved in Bangladesh compared to India. Child undernutrition had significant relations with maternal undernutrition in both countries. Girls in Bangladesh had slightly better nutritional status than boys. In Bangladesh, lack of formal education among mothers was a leading cause of child undernutrition. Stunting and underweight coexist with low household wealth index in both counties. Conclusions The research revealed that various factors were associated with child undernutrition in Bengalis. It has been proposed that programmes promoting maternal education and nutrition, along with household wealth index be prioritised. The study recommends that the Governments of Bangladesh and India should increase the budget for health of children so as to reach the sustainable development goals
Concept of swarming and synchrony in aquatic animal movements: Comment on “Control of movement of underwater swimmers: Animals, simulated animates and swimming robots” by Gordleeva et al.
No full textCoprime networks of the composite numbers: Pseudo-randomness and synchronizability
No full textIn this paper, we propose a network whose nodes are labeled by the composite numbers and two nodes are connected by an undirected link if they are relatively prime to each other. As the size of the network increases, the network will be connected whenever the largest possible node index n≥49. To investigate how the nodes are connected, we analytically describe that the link density saturates to 6/π2, whereas the average degree increases linearly with slope 6/π2 with the size of the network. To investigate how the neighbors of the nodes are connected to each other, we find the shortest path length will be at most 3 for 49≤n≤288 and it is at most 2 for n≥289. We also derive an analytic expression for the local clustering coefficients of the nodes, which quantifies how close the neighbors of a node to form a triangle. We also provide an expression for the number of r-length labeled cycles, which indicates the existence of a cycle of length at most O(logn). Finally, we show that this graph sequence is actually a sequence of weakly pseudo-random graphs. We numerically verify our observed analytical results. As a possible application, we have observed less synchronizability (the ratio of the largest and smallest positive eigenvalue of the Laplacian matrix is high) as compared to Erdős–Rényi random network and Barabási–Albert network. This unusual observation is consistent with the prolonged transient behaviors of ecological and predator–prey networks which can easily avoid the global synchronization
Cops and Robber on butterflies, grids, and AT-free graphs
No full textCOPS AND ROBBER is a well-studied two player pursuit-evasion game played on a graph. In this game, a set of cops, controlled by the first player, tries to capture the position of a robber, controlled by the second player. The cop number of a graph is the minimum number of cops required to capture the robber in the graph. A group of cops guard a subgraph if they can ensure that the robber cannot enter the subgraph without getting captured immediately. We study the applications of guarding to provide new bounds and improve existing bounds for several graph classes. In particular, we show that the cop number for butterfly networks and for solid grids is two. We also construct a partial grid with cop number 3 establishing that partial grids have same cop number as their superclass planar graphs. We also consider three well-studied variants of COPS AND ROBBER: COPS AND FAST ROBBER, COPS AND ATTACKING ROBBER, and SURROUNDING CNR. We improve the existing bounds for the cop number of multidimensional grids for both COPS AND ATTACKING ROBBER and SURROUNDING CNR. Finally, we consider COPS AND FAST ROBBER on AT-free graphs to improve the existing bounds on the cop number for this game
Credit Markets with Time-Inconsistent Agents and Strategic Loan Default
No full textWe study credit contracts under a life-cycle setting where time-inconsistent agents lack the internal commitment to stick to consumption plans and external commitment to repaying loans. With unrestricted credit, agents with only internal commitment problems may overborrow. If, additionally, they face external commitment problems, lenders endogenously impose borrowing limits similar to the ability-to-repay rules consumer financial protection agencies impose. Even with restricted credit access, except in exceptional cases, agents suffering from the twin commitment problems can achieve, at most, fully sophisticated allocations. The government can achieve the first-best allocations if and only if it is assisted with endogenously imposed borrowing limits
DEPTH OF BINOMIAL EDGE IDEALS IN TERMS OF DIAMETER AND VERTEX CONNECTIVITY
No full textLet G be a simple connected noncomplete graph and JG be its binomial edge ideal in a polynomial ring S. Using certain invariants associated to graphs, say U(G), Banerjee and Núñez-Betancourt gave an upper bound for the depth of S/JG, and Rouzbahani Malayeri, Saeedi Madani and Kiani obtained a lower bound, say L(G). Hibi and Saeedi Madani gave a structural classification of graphs satisfying L(G) = U(G). In this article, we give structural classification of graphs satisfying L(G) + 1 = U(G). We also compute the depth of S/JG for all such graphs G
Discovery of Miocene whale fall fauna from India: Taphonomy and palaeoecology of a vertebrate-invertebrate assemblage
No full textHitherto unreported whale fall fauna has been found from the Lower Miocene of Khari Nadi Formation of Kutch, India.This vertebrate-invertebrate assemblage comprises jumbled up bone fragments of different parts of the whale along with molluscs and echinoids. Some representatives in this assemblage are characteristic whale fall fauna and some are characteristic shallow marine fauna. The molluscs belong to the families Buccinidae, Provannidae, Naticidae, Turritellidae, Borsoniidae, Volutidae, Haminoeidae, Cypraeidae, Strombidae, Rostelleriidae, Cassidae, Osteridae, Veneridae, Astartidae and the echinoids to family Spatangidae and Schizasteridae. The present study reveals that the deposition of this entire assemblage was in a shallow marine environment and also sheds some light on the molluscan association related to a whale fall from the western Indian sea waters in the Lower Miocene
Discriminant and integral basis of number fields defined by exponential Taylor polynomials
No full textLet Kn = ℚ(αn) be a family of algebraic number fields where αn ϵ ℂ is a root of the nth exponential Taylor polynomial (equation presented) In this paper, we give a formula for the exact power of any prime p dividing the discriminant of Kn in terms of the p-adic expansion of n. An explicit p-integral basis of Kn is also given for each prime p. These p-integral bases quickly lead to the construction of an integral basis of Kn
Discriminative Deep Canonical Correlation Analysis for Multi-View Data
No full textOver the past few years, multimodal data analysis has emerged as an inevitable method for identifying sample categories. In the multi-view data classification problem, it is expected that the joint representation should include the supervised information of sample categories so that the similarity in the latent space implies the similarity in the corresponding concepts. Since each view has different statistical properties, the joint representation should be able to encapsulate the underlying nonlinear data distribution of the given observations. Another important aspect is the coherent knowledge of the multiple views. It is required that the learning objective of the multi-view model efficiently captures the nonlinear correlated structures across different modalities. In this context, this article introduces a novel architecture, termed discriminative deep canonical correlation analysis (D2CCA), for classifying given observations into multiple categories. The learning objective of the proposed architecture includes the merits of generative models to identify the underlying probability distribution of the given observations. In order to improve the discriminative ability of the proposed architecture, the supervised information is incorporated into the learning objective of the proposed model. It also enables the architecture to serve as both a feature extractor as well as a classifier. The theory of CCA is integrated with the objective function so that the joint representation of the multi-view data is learned from maximally correlated subspaces. The proposed framework is consolidated with corresponding convergence analysis. The efficacy of the proposed architecture is studied on different domains of applications, namely, object recognition, document classification, multilingual categorization, face recognition, and cancer subtype identification with reference to several state-of-the-art methods