567,515 research outputs found
Efficient Online Timed Pattern Matching by Automata-Based Skipping
The timed pattern matching problem is an actively studied topic because of
its relevance in monitoring of real-time systems. There one is given a log
and a specification (given by a timed word and a timed automaton
in this paper), and one wishes to return the set of intervals for which the log
, when restricted to the interval, satisfies the specification
. In our previous work we presented an efficient timed pattern
matching algorithm: it adopts a skipping mechanism inspired by the classic
Boyer--Moore (BM) string matching algorithm. In this work we tackle the problem
of online timed pattern matching, towards embedded applications where it is
vital to process a vast amount of incoming data in a timely manner.
Specifically, we start with the Franek-Jennings-Smyth (FJS) string matching
algorithm---a recent variant of the BM algorithm---and extend it to timed
pattern matching. Our experiments indicate the efficiency of our FJS-type
algorithm in online and offline timed pattern matching
Equilibrium unemployment in a general equilibrium model with taxes
The ratio of unemployed to vacancies has risen sharply in the UK after the recession of 2008/09. How harmful is it for the long run growth, equity and efficiency and what sorts of long run cycles does it generate in the economy? With a dynamic computable general equilibrium model with Pissarides (1979, 2011) and Mortensen and Pissarides (1994) type equilibrium unemployment, impacts of tax-transfer programmes are assessed for the UK. The model contains more desirable structure of households and production sectors and includes more type of shocks in preferences, technology, trade and policy instruments for stochastic analyses than is usual in DSGE models. It assesses growth and cycles as well as equity and efficiency effects of policies simultaneously. Improvements in the matching technology lowers the equilibrium unemployment and raises the long-run growth rate and life time utilities of households and reduces long run cycles. Matching could be made more efficient by influencing the relative price system by optimal set of tax and transfer instruments. Better matching techniques can make transition of job-seekers to employment more efficient so that the intertemporal labour-leisure and consumption-saving decisions have greater impacts on growth and redistribution reducing fluctuations in the economy
Spin-filter tunnel junction with matched Fermi surfaces
Efficient injection of spin-polarized current into a semiconductor is a basic
prerequisite for building semiconductor-based spintronic devices. Here, we use
inelastic electron tunneling spectroscopy to show that the efficiency of
spin-filter-type spin injectors is limited by spin scattering of the tunneling
electrons. By matching the Fermi-surface shapes of the current injection source
and target electrode material, spin injection efficiency can be significantly
increased in epitaxial ferromagnetic insulator tunnel junctions. Our results
demonstrate that not only structural but also Fermi-surface matching is
important to suppress scattering processes in spintronic devices.Comment: 5 pages, 4 figure
A labor market with targeted wage offers
We model a market for highly skilled workers, such as the academic job market. The outputs of ?rm-worker matches are heterogeneous and common knowledge. Wage setting is synchronous with search: ?rms simultaneously make one personalized offer each to the worker of their choice. With large frictions (delay costs), efficient coordination is not possible, but for small frictions efficient matching with Diamond-type monopsony wages is an equilibrium.
Full Flow: Optical Flow Estimation By Global Optimization over Regular Grids
We present a global optimization approach to optical flow estimation. The
approach optimizes a classical optical flow objective over the full space of
mappings between discrete grids. No descriptor matching is used. The highly
regular structure of the space of mappings enables optimizations that reduce
the computational complexity of the algorithm's inner loop from quadratic to
linear and support efficient matching of tens of thousands of nodes to tens of
thousands of displacements. We show that one-shot global optimization of a
classical Horn-Schunck-type objective over regular grids at a single resolution
is sufficient to initialize continuous interpolation and achieve
state-of-the-art performance on challenging modern benchmarks.Comment: To be presented at CVPR 201
Assortative Matching and Reputation
Consider Becker's classic 1963 matching model, with unobserved fixed types and stochastic publicly observed output. If types are complementary, then matching is assortative in the known Bayesian posteriors (the 'reputations'). We discover a robust failure of Becker's result in the simplest dynamic two type version of this world. Assortative matching is generally neither efficient nor an equilibrium for high discount factors. In a labor theoretic rationale, we show that assortative matching fails around the highest (lowest) reputation agents for 'low-skill (high-skill) concealing' technologies. We then find that as the number of production outcomes grows, almost all technologies are of either form. Our theory implies the dynamic result that high-skill matches eventually break up. It also reveals that the induced information rents create discontinuities in the wage profile. This in turn produces life-cycle effects: young workers are paid less than their static marginal product, and old workers more.assortative matching, incomplete information, wages, Bayesian posterior, value function
The effect of plasma-core induced self-guiding on phase matching of high-order harmonic generation in gases
In this work we numerically study a self-guiding process in which ionization
plays a dominant role and analyze its effect on high-order harmonic generation
(HHG) in gases. Although this type of self-guiding --- termed as plasma-core
induced self-guiding in previous works --- limits the achievable cut-off by
regulating the intensity of the laser beam, it provides favorable conditions
for phase matching, which is indispensable for high-flux gas high-harmonic
sources. To underline the role of self-guiding in efficient HHG, we investigate
the time-dependent phase matching conditions in the guided beam and show how
the spatio-temporally constant fundamental intensity contributes to the
constructive build-up of the harmonic field in a broad photon-energy range up
to the provided cut-off.Comment: 14 pages, 7 figure
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