Search results for "sampling"
showing 10 items of 788 documents
Further development of integrated threat theory and intergroup contact: a reply to Aberson (2015)
2016
ABSTRACTThis essay furthers a dialogue about the theoretical and statistical merits of Croucher's [(2013). Integrated threat theory and acceptance of immigrant assimilation: An analysis of Muslim immigration in Western Europe. Communication Monographs, 80, 46–62] study exploring the relationships between threat from an immigrant group, belief that an immigrant wants to assimilate, and intergroup contact. Key points of divergence include assertions that (a) the relationships in the original piece are counter to previous literature/relationships, (b) the correlations presented are implausible, (c) the magnitude of the relationships is too strong, and (d) the manuscript has “odd” multiple regr…
Sampling in Local Tourism Quantification: Critical Issues and Field Experience
2013
The aim of this paper is to detail some issues relating to tourist sampling by means of three case studies. Tourism quantification issues and solutions will be illustrated in three paradgmatic situations: sampling in a self-contained context with multiple access points (an Island in Aeolian archipelago), tourism in a seaside town, and nautical tourism. In these contexts the issue of building a space-time grid to circumscribe the target population is made more complex by the mobile nature of these populations.
Frozen or dynamic? : An atomistic simulation perspective on the timescales of electrochemical reactions
2023
Electrochemical systems span a wide range of timescales, and several recent works have put forth the idea that the reaction environment should remain frozen and out of equilibrium during electrochemical electron or proton transfer reactions. Furthermore, simplified treatments of the electrochemical interface model the solvent and ions as frozen molecules. However, the claims and practices of a frozen environment strongly clash with most theoretical and simulation approaches developed to study electrochemical reaction rates. It has also been suggested that the electrode potential should not be fixed when simulating reaction rates due to conductivity limitations, which indicates constant pote…
Dead wood profile of a semi-natural boreal forest – implications for sampling
2019
Dead wood profile of a forest is a useful tool for describing forest characteristics and assessing forest disturbance history. Nevertheless, there are few studies on dead wood profiles, including both coarse and fine dead wood, and on the effect of sampling intensity on the dead wood estimates. In a semi-natural boreal forest, we measured every dead wood item over 2 cm in diameter from 80 study plots. From eight plots, we further recorded dead wood items below 2 cm in diameter. Based on these data we constructed the full dead wood profile, i.e. the overall number of dead wood items and their distribution among different tree species, volumes of different size and decay stage categories. We …
Satisfação Profissional no Docente Dominicano: Antecedentes Profissionais
2019
Resumen La satisfacción laboral del colectivo docente ha sido estudiada desde diversas perspectivas, debido a los importantes efectos que esta puede tener tanto a nivel económico como a nivel organizacional. La muestra empleada en este trabajo se compone de 978 docentes dominicanos, y fue obtenida mediante un muestreo estratificado, y, por tanto, representativo de la población. En este estudio se examina un modelo de ecuaciones estructurales en el cual el contexto de trabajo y las condiciones laborales afectan el burnout y el engagement de los profesores. A su vez, se plantea que burnout y engagement afectan la satisfacción laboral docente. El modelo ajustó a los datos: x2(223)= 1089.9, p<.…
A Shape-based Statistical Method to Retrieve 2D TRUS-MR Slice Correspondence for Prostate Biopsy
2012
International audience; This paper presents a method based on shape-context and statistical measures to match interventional 2D Trans Rectal Ultrasound (TRUS) slice during prostate biopsy to a 2D Magnetic Resonance (MR) slice of a pre-acquired prostate volume. Accurate biopsy tissue sampling requires translation of the MR slice information on the TRUS guided biopsy slice. However, this translation or fusion requires the knowledge of the spatial position of the TRUS slice and this is only possible with the use of an electro-magnetic (EM) tracker attached to the TRUS probe. Since, the use of EM tracker is not common in clinical practice and 3D TRUS is not used during biopsy, we propose to per…
Multispectral filter arrays: Recent advances and practical implementation
2014
Thanks to some technical progress in interferencefilter design based on different technologies, we can finally successfully implement the concept of multispectral filter array-based sensors. This article provides the relevant state-of-the-art for multispectral imaging systems and presents the characteristics of the elements of our multispectral sensor as a case study. The spectral characteristics are based on two different spatial arrangements that distribute eight different bandpass filters in the visible and near-infrared area of the spectrum. We demonstrate that the system is viable and evaluate its performance through sensor spectral simulation. Multispectral filter arrays: Recent advan…
Database Species-Area Relationships in Palaearctic Grasslands
2012
The Database Species-Area Relationships in Palaearctic Grasslands (GIVD ID EU-00-003) is an initiative of the European Dry Grassland Group (EDGG) and primarily functions as repository for all data sampled during the EDGG Research Expeditions. During these expeditions two types of highly standardised sampling of dry grassland vegetation in the Palaearctic realm are carried out: (i) nested-plot sampling on squares of 0.0001, 0.001, 0.01, 0.1, 1, 10, and 100 m2; (ii) additional normal releves of 10-m2 plots. For all plot sizes, the terricolous vascular plants, bryophytes, and lichens are recorded that are superficially present (shoot presence). Additionally, for all 10-m2 plots species cover i…
SCOPE-Based Emulators for Fast Generation of Synthetic Canopy Reflectance and Sun-Induced Fluorescence Spectra
2017
Progress in advanced radiative transfer models (RTMs) led to an improved understanding of reflectance (R) and sun-induced chlorophyll fluorescence (SIF) emission throughout the leaf and canopy. Among advanced canopy RTMs that have been recently modified to deliver SIF spectral outputs are the energy balance model SCOPE and the 3D models DART and FLIGHT. The downside of these RTMs is that they are computationally expensive, which makes them impractical in routine processing, such as scene generation and retrieval applications. To bypass their computational burden, a computationally effective technique has been proposed by only using a limited number of model runs, called emulation. The idea …
Understanding the microbial biogeography of ancient human dentitions to guide study design and interpretation
2021
AbstractThe oral cavity is a heterogeneous environment, varying in factors such as pH, oxygen levels, and salivary flow. These factors affect the microbial community composition and distribution of species in dental plaque, but it is not known how well these patterns are reflected in archaeological dental calculus. In most archaeological studies, a single sample of dental calculus is studied per individual and is assumed to represent the entire oral cavity. However, it is not known if this sampling strategy introduces biases into studies of the ancient oral microbiome. Here, we present the results of a shotgun metagenomic study of a dense sampling of dental calculus from four Chalcolithic i…