Search results for "import"

Crowd Models for Emergency Evacuation: A Review Targeting Human-Centered Sensing

2013

Emergency evacuation of crowds is a fascinating phenomenon that has attracted researchers from various fields. Better understanding of this class of crowd behavior opens up for improving evacuation policies and smarter design of buildings, increasing safety. Recently, a new class of disruptive technology has appeared: Human-centered sensing which allows crowd behavior to be monitored in real-time, and provides the basis for real-time crowd control. The question then becomes: to what degree can previous crowd models incorporate this development, and what areas need further research? In this paper, we provide a survey that describes some widely used crowd models and discuss their advantages a…

Importance sampling for Lambda-coalescents in the infinitely many sites model

2011

We present and discuss new importance sampling schemes for the approximate computation of the sample probability of observed genetic types in the infinitely many sites model from population genetics. More specifically, we extend the 'classical framework', where genealogies are assumed to be governed by Kingman's coalescent, to the more general class of Lambda-coalescents and develop further Hobolth et. al.'s (2008) idea of deriving importance sampling schemes based on 'compressed genetrees'. The resulting schemes extend earlier work by Griffiths and Tavar\'e (1994), Stephens and Donnelly (2000), Birkner and Blath (2008) and Hobolth et. al. (2008). We conclude with a performance comparison o…

Bush, camino del Nobel

2003

Adaptive Importance Sampling: The past, the present, and the future

2017

A fundamental problem in signal processing is the estimation of unknown parameters or functions from noisy observations. Important examples include localization of objects in wireless sensor networks [1] and the Internet of Things [2]; multiple source reconstruction from electroencephalograms [3]; estimation of power spectral density for speech enhancement [4]; or inference in genomic signal processing [5]. Within the Bayesian signal processing framework, these problems are addressed by constructing posterior probability distributions of the unknowns. The posteriors combine optimally all of the information about the unknowns in the observations with the information that is present in their …

Adaptive Population Importance Samplers: A General Perspective

2016

Importance sampling (IS) is a well-known Monte Carlo method, widely used to approximate a distribution of interest using a random measure composed of a set of weighted samples generated from another proposal density. Since the performance of the algorithm depends on the mismatch between the target and the proposal densities, a set of proposals is often iteratively adapted in order to reduce the variance of the resulting estimator. In this paper, we review several well-known adaptive population importance samplers, providing a unified common framework and classifying them according to the nature of their estimation and adaptive procedures. Furthermore, we interpret the underlying motivation …

Group Metropolis Sampling

2017

Monte Carlo (MC) methods are widely used for Bayesian inference and optimization in statistics, signal processing and machine learning. Two well-known class of MC methods are the Importance Sampling (IS) techniques and the Markov Chain Monte Carlo (MCMC) algorithms. In this work, we introduce the Group Importance Sampling (GIS) framework where different sets of weighted samples are properly summarized with one summary particle and one summary weight. GIS facilitates the design of novel efficient MC techniques. For instance, we present the Group Metropolis Sampling (GMS) algorithm which produces a Markov chain of sets of weighted samples. GMS in general outperforms other multiple try schemes…

Theoretical Foundations of the Monte Carlo Method and Its Applications in Statistical Physics

2002

In this chapter we first introduce the basic concepts of Monte Carlo sampling, give some details on how Monte Carlo programs need to be organized, and then proceed to the interpretation and analysis of Monte Carlo results.

Sul rilievo costituzionale della responsabilità dirigenziale nell’attuale sistema dei rapporti tra politica e amministrazione

2019

L'articolo intende mettere in luce gli elementi caratterizzanti ed innovativi della responsabilità per risultati dei dirigenti pubblici italiani ed il ruolo di garanzia costituzionale che questa nuova forma di responsabilità può assolvere nell'attuale assetto dei rapporti tra politica e amministrazione. This paper argues for the Constitutional Importance of Accountability for Performance of Public Management in the Italian Legal System.

Simúlidos (Diptera: Simuliidae) de los ríos de la Comunidad Valenciana: Implicaciones en la salud pública y su control

2018

Los simúlidos (Diptera: Simuliidae) se encuentran distribuidos por casi todo el mundo. Su presencia está ampliamente influenciada por la disponibilidad de cursos de agua con flujo, necesarios para el desarrollo de los estados inmaduros (ADLER & McCREADIE, 2002), ocupando ambientes que van desde cursos temporales hasta grandes ríos. Los simúlidos crían en aguas corrientes, se les puede encontrar tanto en arroyos y torrentes de montaña como en los lentos flujos de agua de los ríos en sus tramos bajos. Además, existen unas pocas especies las cuales se han adaptado a flujos de agua tan escasos donde incluso la corriente es casi imperceptible (BURGER, 1987). En cualquier caso, se sabe que cierto…

Research on the history of Scandinavian summer and seaside tourism – transnational and transregional perspectives?

2013

The purpose of this article is to investigate important research on the history of Scandinavian tourism conducted between the 1980s and the present. More specifically, it deals with research on summer and seaside tourism history in the Skagerrak–Kattegat and some parts of the North Sea region (southeastern Norway, Bohuslan in southwestern Sweden, and Jutland in western Denmark) from the late 1800s through the twentieth century. Although the publications chosen for this historiographical analysis are primarily anthologies and articles in scholarly reports, some monographs have been included as well. The ensuing discussion includes reflections on how the selected geographical spaces may have …