5,917 research outputs found

    An Improved Tax Scheme for Selfish Routing

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    We study the problem of routing traffic for independent selfish users in a congested network to minimize the total latency. The inefficiency of selfish routing motivates regulating the flow of the system to lower the total latency of the Nash Equilibrium by economic incentives or penalties. When applying tax to the routes, we follow the definition of [Christodoulou et al, Algorithmica, 2014] to define ePoA as the Nash total cost including tax in the taxed network over the optimal cost in the original network. We propose a simple tax scheme consisting of step functions imposed on the links. The tax scheme can be applied to routing games with parallel links, affine cost functions and single-commodity networks to lower the ePoA to at most 4/3 - epsilon, where epsilon only depends on the discrepancy between the links. We show that there exists a tax scheme in the two link case with an ePoA upperbound less than 1.192 which is almost tight. Moreover, we design another tax scheme that lowers ePoA down to 1.281 for routing games with groups of links such that links in the same group are similar to each other and groups are sufficiently different

    Research Notes : Taiwan : A spontaneous narrow-leaflet mutant

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    At the Asian Vegetable Research and Development Center, developing improved vegetable soybeans is one of the objectives. In accomplishing that objective, one of the crosses involved AGS 188, PI 157424 from Maturity Group IV and G 10381, cultivar \u27Kaohsiung\u27 No. 8 released by the Kaohsiung District Agricultural Improvement Station in Pingtung, Taiwan. The F1 and F2 progenies of the cross were normal

    On the Influencing Factors of Dictionary App Interface Design for the Elders

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    AbstractEnglish learning is becoming one of the popular movements towards the Globalization. In recent years especially, more people use smartphones to learn English. However, it was found in the current market that most dictionary apps were designed for the younger generation and neglected the needs of the elderly. The issue of memory over-load turned out to be the critical problem of the usability for the elderly, due to the complex menu structures. Thus this study is meant to explore a suitable menu structure for the senior user, and provide suggestions for the relative researches.The study results are:1.Gender: There is no significant between male and female in the operating performance.2.Menu structure: the performance of the hybrid structure is superior to the linear structure.3.Display mode: There is no significant between the horizontal and vertical display modes in operating performance.4.Task Complexity: A positive ratio between task complexity and menu topological structure was revealed, the harder the task complexity, the better performance of mixed structure can be expected

    EVALUATION OF RECEIVING ABILITY OF TEENAGE MALE TABLE TENNIS PLAYERS IN TAIWAN

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    The purpose of this study was to evaluate the forehand receiving ability of teenage male table tennis players. Thirty-nine male players consist of skill levels from junior to senior high school students and national squads were selected. This assessment involves three tests: basic control, judgment, and match-like condition simulation. We found under the basic control test, the junior high school players performed poorer in downspin and left-side downspin in the aspect of accuracy (

    Dirac-Electrons-Mediated Magnetic Proximity Effect in Topological Insulator / Magnetic Insulator Heterostructures

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    The possible realization of dissipationless chiral edge current in a topological insulator / magnetic insulator heterostructure is based on the condition that the magnetic proximity exchange coupling at the interface is dominated by the Dirac surface states of the topological insulator. Here we report a polarized neutron reflectometry observation of Dirac electrons mediated magnetic proximity effect in a bulk-insulating topological insulator (Bi0.2_{0.2}Sb0.8_{0.8})2_{2}Te3_{3} / magnetic insulator EuS heterostructure. We are able to maximize the proximity induced magnetism by applying an electrical back gate to tune the Fermi level of topological insulator to be close to the charge neutral point. A phenomenological model based on diamagnetic screening is developed to explain the suppressed proximity induced magnetism at high carrier density. Our work paves the way to utilize the magnetic proximity effect at the topological insulator/magnetic insulator hetero-interface for low-power spintronic applications.Comment: 5 pages main text with 4 figures; 2 pages supplemental materials; suggestions and discussions are welcome
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