6,686 research outputs found
Plancherel-Rotach Asymptotics of Second-Order Difference Equations with Linear Coefficients
In this paper, we provide a complete Plancherel-Rotach asymptotic analysis of
polynomials that satisfy a second-order difference equation with linear
coefficients. According to the signs of the parameters, we classify the
difference equations into six cases and derive explicit asymptotic formulas of
the polynomials in the outer and oscillatory regions, respectively. It is
remarkable that the zero distributions of the polynomials may locate on the
imaginary line or even on a sideways Y-shape curve in some cases
A Unified And Green Platform For Smartphone Sensing
Smartphones have become key communication and entertainment devices in people\u27s daily life. Sensors on (or attached to) smartphones can enable attractive sensing applications in different domains, including environmental monitoring, social networking, healthcare, transportation, etc. Most existing smartphone sensing systems are application-specific. How to leverage smartphones\u27 sensing capability to make them become unified information providers for various applications has not yet been fully explored. This dissertation presents a unified and green platform for smartphone sensing, which has the following desirable features: 1) It can support various smartphone sensing applications; 2) It is personalizable; 2) It is energy-efficient; and 3) It can be easily extended to support new sensors. Two novel sensing applications are built and integrated into this unified platform: SOR and LIPS. SOR is a smartphone Sensing based Objective Ranking (SOR) system. Different from a few subjective online review and recommendation systems (such as Yelp and TripAdvisor), SOR ranks a target place based on data collected via smartphone sensing. LIPS is a system that learns the LIfestyles of mobile users via smartPhone Sensing (LIPS). Combining both unsupervised and supervised learning, a hybrid scheme is proposed to characterize lifestyle and predict future activities of mobile users. This dissertation also studies how to use the cloud as a coordinator to assist smartphones for sensing collaboratively with the objective of reducing sensing energy consumption. A novel probabilistic model is built to address the GPS-less energy-efficient crowd sensing problem. Provably-good approximation algorithms are presented to enable smartphones to sense collaboratively without accurate locations such that sensing coverage requirements can be met with limited energy consumption
A Checklist and Key to Species of the Genus Betacixius Matsumura (Hemiptera: Fulgoromorpha: Cixiidae) with Descriptions of Two New Species from Guizhou Province, China
ABSTRACT Two new species of Betacixius Matsumura, 1914 (Hemiptera: Fulgoromorpha: Cixiidae: Cixiini), B. bispinus Zhang and Chen sp. nov. (China: Guizhou) and B. flagellihamus Zhang and Chen sp. nov. (China: Guizhou), from southwest China, are described and illustrated. A key for identifying 23 known species of Betacixius is provided
Uniform Asymptotics of Orthogonal Polynomials Arising from Coherent States
In this paper, we study a family of orthogonal polynomials
arising from nonlinear coherent states in quantum optics. Based on the
three-term recurrence relation only, we obtain a uniform asymptotic expansion
of as the polynomial degree tends to infinity. Our asymptotic
results suggest that the weight function associated with the polynomials has an
unusual singularity, which has never appeared for orthogonal polynomials in the
Askey scheme. Our main technique is the Wang and Wong's difference equation
method. In addition, the limiting zero distribution of the polynomials
is provided
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