2,217 research outputs found

    Charge order and phase segregation in overdoped bilayer manganites

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    There have been recent reports of charge ordering around x=0.5x=0.5 in the bilayer manganites. At x=0.5x=0.5, there appears to be a coexistence region of layered A-type antiferromagnetc and charge order. There are also reports of orbital order in this region without any Jahn-Teller effect. Based on physical grounds, this region is investigated from a model that incorporates the two ege_g orbitals at each Mn site and a near-neighbour Coulomb repulsion. It is shown that there indeed is both charge and orbital order close to the half-doped region coincident with a layered magnetic structure. Although the orbital order is known to drive the magnetic order, the layered magnetic structure is also favoured in this system by the lack of coherent transport across the planes and the reduced dimensionality of the lattice. The anisotropic hopping across the ege_g orbitals and the underlying layered structure largely determine the orbital arrangements in this region, while the charge order is primarily due to the long range interactions.Comment: 6 pages, 6 figure

    Antiferromagnetism and Superconductivity in a Model with Extended Pairing Interactions

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    The competition between antiferromagnetism and the d+idd+id superconducting state is studied in a model with near and next near neighbour interactions in the absence of any on-site repulsion. A mean field study shows that it is possible to have simultaneous occurrence of an antiferromagnetic and a singlet d+idd+id superconducting state in this model. In addition, such a coexistence generates a triplet d+idd+id superconducting order parameter with centre of mass momentum Q=(π,π)Q=(\pi, \pi) {\it dynamically} having the same orbital symmetry as the singlet superconductor. Inclusion of next nearest neighbour hopping in the band stabilises the dxyd_{xy} superconducting state away from half filling, the topology of the phase diagram, though, remains similar to the near neighbour model. In view of the very recent observation of a broad region of coexistence of antiferrmagnetic and unconventional superconducting states in organic superconductors, the possibility of observation of the triplet state has been outlined.Comment: 12 pages(tex file), 7 figures (ps files

    Evolutionary Economics, Classical Development Economics, and the History of Economic Policy: A Plea for Theorizing by Inclusion

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    The author argues that in order to create a qualitative understanding of the factors polarizing the world in growing wealth and growing poverty there is a need to create economics by inclusion, a system where all relevant factors, some of which have been part of the economic discourse for centuries, but also elements (like the different effects of process and product innovations) that are part of evolutionary economics itself, are considered simultaneously. According to the author, this historical/institutional approach to economics would benefit especially the Third World. Moreover, the economics by inclusion should also open the way for policies of inclusion, a system that will put the accent on the wellbeing of the majority and not on the growth of the export sector.

    Double exchange and orbital correlations in electron-doped manganites

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    A double exchange model for degenerate ege_g orbitals with intra- and inter-orbital interactions has been studied for the electron doped manganites A1x_{1-x}Bx_{x}MnO3_3 (x>0.5x > 0.5). We show that such a model reproduces the observed phase diagram and orbital ordering in the intermediate bandwidth regime and the Jahn-Teller effect, considered to be crucial for the region x<0.5x<0.5, does not play a major role in this region. Brink and Khomskii have already pointed this out and stressed the relevance of the anistropic hopping across the degenerate ege_g orbitals in the infinite Hund's coupling limit. From a more realistic calculation with finite Hund's coupling, we show that inclusion of interactions stabilizes the C-phase, the antiferromagnetic metallic A-phase moves closer to x=0.5x=0.5 while the ferromagnetic phase shrinks. This is in agreement with the recent observations of Kajimoto et. al. and Akimoto et. al.Comment: text 9 pages, 5 figure

    Data dependent energy modelling for worst case energy consumption analysis

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    Safely meeting Worst Case Energy Consumption (WCEC) criteria requires accurate energy modeling of software. We investigate the impact of instruction operand values upon energy consumption in cacheless embedded processors. Existing instruction-level energy models typically use measurements from random input data, providing estimates unsuitable for safe WCEC analysis. We examine probabilistic energy distributions of instructions and propose a model for composing instruction sequences using distributions, enabling WCEC analysis on program basic blocks. The worst case is predicted with statistical analysis. Further, we verify that the energy of embedded benchmarks can be characterised as a distribution, and compare our proposed technique with other methods of estimating energy consumption

    IMPACT OF ELECTRIC POWER SECTOR REFORMS ON FARM INCOMES IN INDIA

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    The supply of electricity to the agricultural sector (largely for pumping groundwater) is heavily subsidized in India. Using data from a household survey in the state of Haryana, a profit function estimated to analyze the impact of increase in tariffs accompanied by improvement in conditions of supply on farm incomes.Agricultural Finance, Resource /Energy Economics and Policy,

    An EcoSage Assistant: Towards Building A Multimodal Plant Care Dialogue Assistant

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    In recent times, there has been an increasing awareness about imminent environmental challenges, resulting in people showing a stronger dedication to taking care of the environment and nurturing green life. The current $19.6 billion indoor gardening industry, reflective of this growing sentiment, not only signifies a monetary value but also speaks of a profound human desire to reconnect with the natural world. However, several recent surveys cast a revealing light on the fate of plants within our care, with more than half succumbing primarily due to the silent menace of improper care. Thus, the need for accessible expertise capable of assisting and guiding individuals through the intricacies of plant care has become paramount more than ever. In this work, we make the very first attempt at building a plant care assistant, which aims to assist people with plant(-ing) concerns through conversations. We propose a plant care conversational dataset named Plantational, which contains around 1K dialogues between users and plant care experts. Our end-to-end proposed approach is two-fold : (i) We first benchmark the dataset with the help of various large language models (LLMs) and visual language model (VLM) by studying the impact of instruction tuning (zero-shot and few-shot prompting) and fine-tuning techniques on this task; (ii) finally, we build EcoSage, a multi-modal plant care assisting dialogue generation framework, incorporating an adapter-based modality infusion using a gated mechanism. We performed an extensive examination (both automated and manual evaluation) of the performance exhibited by various LLMs and VLM in the generation of the domain-specific dialogue responses to underscore the respective strengths and weaknesses of these diverse models
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