2,432 research outputs found

    Singular components of spectral measures for ergodic Jacobi matrices

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    For ergodic 1d Jacobi operators we prove that the random singular components of any spectral measure are almost surely mutually disjoint as long as one restricts to the set of positive Lyapunov exponent. In the context of extended Harper's equation this yields the first rigorous proof of the Thouless' formula for the Lyapunov exponent in the dual regions.Comment: to appear in the Journal of Mathematical Physics, vol 52 (2011

    Программные решения организации работы с ЭМК на мобильных устройствах в off-line режиме

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    The article deals with software solutions for e-health card under the access to the services of a medical information system. Consideration of some cross-platform solution for e-health card, as well as highlights the main approaches to the development of this service

    Counting Small Induced Subgraphs with Edge-monotone Properties

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    We study the parameterized complexity of #IndSub(Φ\Phi), where given a graph GG and an integer kk, the task is to count the number of induced subgraphs on kk vertices that satisfy the graph property Φ\Phi. Focke and Roth [STOC 2022] completely characterized the complexity for each Φ\Phi that is a hereditary property (that is, closed under vertex deletions): #IndSub(Φ\Phi) is #W[1]-hard except in the degenerate cases when every graph satisfies Φ\Phi or only finitely many graphs satisfy Φ\Phi. We complement this result with a classification for each Φ\Phi that is edge monotone (that is, closed under edge deletions): #IndSub(Φ\Phi) is #W[1]-hard except in the degenerate case when there are only finitely many integers kk such that Φ\Phi is nontrivial on kk-vertex graphs. Our result generalizes earlier results for specific properties Φ\Phi that are related to the connectivity or density of the graph. Further, we extend the #W[1]-hardness result by a lower bound which shows that #IndSub(Φ\Phi) cannot be solved in time f(k)V(G)o(logk/loglogk)f(k) \cdot |V(G)|^{o(\sqrt{\log k/\log\log k})} for any function ff, unless the Exponential-Time Hypothesis (ETH) fails. For many natural properties, we obtain even a tight bound f(k)V(G)o(k)f(k) \cdot |V(G)|^{o(k)}; for example, this is the case for every property Φ\Phi that is nontrivial on kk-vertex graphs for each kk greater than some k0k_0

    Collusive market allocations

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    Collusive schemes by suppliers often take the form of allocating customers or markets among cartel members. We analyze incentives for suppliers to initiate and sustain such a collusive schemes in a repeated procurement setting. We show that, contrary to some prevailing beliefs, staggered (versus synchronized) purchasing does not make collusion more difficult to sustain or initiate. Buyer defensive measures include synchronized rather than staggered purchasing, first-price rather than second-price auctions, more aggressive or secrete reserve prices, longer contract lengths, withholding information, and avoiding observable registration procedures. Inefficiency induced by defensive measures is an often unrecognized social cost of collusive conduct

    Building A Big Data Analytical Pipeline With Hadoop For Processing Enterprise XML Data

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    The current paper shows an end-to-end approach how to process XML files in the Hadoop ecosystem. The work demonstrates a way how to handle problems faced during the analysis of a large amounts of XML files. The paper presents a completed Extract, Load and Transform (ELT) cycle, which is based on the open source software stack Apache Hadoop, which became a standard for processing of a huge amounts of data. This work shows that applying open source solutions to a particular set of problems could not be enough. In fact, most of big data processing open source tools were implemented only to address a limited number of the use cases. This work explains and shows, why exactly specific use cases may require significant extension with a self-developed multiple software components. The use case described in the paper deals with huge amounts of semi-structured XML files, which supposed to be persisted and processed daily

    The contribution of the German building sector to achieve the 1.5 °C target

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    The melting greenhouse gas emissions budget of the German building sector for the 1.5 °C target requires fast counteraction. In this paper, an analysis of the applicable legal and regulatory framework, the funding situation as well as national and international strategies on a transformation towards climate neutrality elucidates that the suggested approaches do not take a holistic view into account. They neglect, that embodied emissions from construction and emissions from operations phases of buildings must be oriented on the remaining budget, as well as material and human resources associated with the required actions. Therefore a framework to decarbonise the German building sector with eleven recommendations for action, which addresses these findings, is developed with a panel of experts. The results clarify, that the focus must be on adapting the existing building stock since renovation processes release significantly fewer emissions than the construction of new buildings. Stricter legal requirements for building envelopes have no significant effect on the reduction of emissions. Instead, fast-acting measures, such as the usage of district heating, photovoltaics, heat pumps, the optimisation of building operation and digitalisation, must be implemented in a prioritised manner to save resources and maintain the emissions budget longer. To be able to align effective measures it is necessary to engage all Stakeholders and to establish reliable political guidance down to the building level
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