Search results for "modelling."

Modelling distribution and habitat preferences of vulnerable species

2011

Predicting future thermal habitat suitability of competing native and invasive fish species: From metabolic scope to oceanographic modelling

2015

Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. Here, we determined the effect of temperature on the aerobic metabolic scope of two competing fish species, one native and one invasive, and we predicted their future thermal habitat suitability.

'Niche Selection' and the evolution of a complex behavior in a changing environment--a simulation.

2000

One of the key problems in theoretical biology is the identification of the mechanisms underlying the evolution of complexity. This paper suggests that some difficulties in current models could be avoided by taking account of “niche selection” as proposed by Waddington [21] and subsequent authors [2]. Computer simulations, in which an evolving population of artificial organisms “selects” the niche(s) that maximize their fitness, are compared with a Control Model in which “Niche Selection” is absent. In the simulations the Niche Selection Model consistently produced a greater number of “fit” organisms than the Control Model; although the Niche Selection Model tended, in general, to produce o…

Integrating species distribution models (SDMs) and phylogeography for two species of AlpinePrimula

2012

The major intention of the present study was to investigate whether an approach combining the use of niche-based palaeodistribution modeling and phylo-geography would support or modify hypotheses about the Quaternary distributional history derived from phylogeographic methods alone. Our study system comprised two closely related species of Alpine Primula. We used species distribution models based on the extant distribution of the species and last glacial maximum (LGM) climate models to predict the distribution of the two species during the LGM. Phylogeographic data were generated using amplified fragment length polymorphisms (AFLPs). In Primula hirsuta, models of past distribution and phylo…

A critical view on temperature modelling for application in weather derivatives markets

2012

In this paper we present a stochastic model for daily average temperature. The model contains seasonality, a low-order autoregressive component and a variance describing the heteroskedastic residuals. The model is estimated on daily average temperature records from Stockholm (Sweden). By comparing the proposed model with the popular model of Campbell and Diebold (2005), we point out some important issues to be addressed when modelling the temperature for application in weather derivatives market.

Measuring the shadow economy and its drivers: the case of peripheral EMU countries

2019

We adopt a long-run perspective to investigate the size of the shadow economy and explore the trends in this area. The analysis is based on a panel of peripheral EMU countries over the period 1965-2015. Our empirical approach relies on a multiple indicators and multiple causes (MIMIC) framework. This approach is a variant of structural equation modelling (SEM). We used two sets of variables, (i.e. potential determinants and indicator variables) to estimate an underlying (unobserved) index that measures the evolution of the shadow economy. Ascertaining the relative importance of the shadow economy enabled analysis of its relationship with other institutional and social issues (e.g. corruptio…

Creencias de los estudiantes de educación secundaria sobre la naturaleza de la ciencia y los modelos científicos: un estudio transversal

2018

Las trayectorias de empleabilidad de los jóvenes que salen del sistema de protección se ven condicionadas por su situación de exclusión social. Nuestra investigación persigue: a) analizar las trayectorias de los jóvenes extutelados y b) examinar cómo sus experiencias vitales y laborales influyen en su situación de exclusión. Se realizó un estudio de casos múltiples con cuatro jóvenes inmigrantes y tres nacionales. La selección de los casos tuvo en cuenta: a) haber estado acogido al sistema de protección, b) haber pasado un mínimo de 6 meses en un programa de inserción laboral, c) haber transcurrido 6 años después de finalizar el proyecto de inserción. En el estudio se utilizaron entrevistas…

First Principles Calculations of Atomic and Electronic Structure of Ti3+Al- and Ti2+Al-Doped YAlO3

2021

M.G.B. appreciates support from the Chongqing Recruitment Program for 100 Overseas Innovative Talents (grant no. 2015013), the Program for the Foreign Experts (grant no. W2017011), Wenfeng High-end Talents Project (grant no. W2016-01) offered by the Chongqing University of Posts and Telecommunications (CQUPT), Estonian Research Council grant PUT PRG111, European Regional Development Fund (TK141), and NCN project 2018/31/B/ST4/00924. This study was supported by a grant from Latvian Research Council No. LZP-2018/1-0214 (for AIP). Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Program H202…

Work-related and personal predictors of COVID-19 transmission: evidence from the UK and USA

2021

ObjectiveTo develop evidence of work-related and personal predictors of COVID-19 transmission.Setting and respondentsData are drawn from a population survey of individuals in the USA and UK conducted in June 2020.Background methodsRegression models are estimated for 1467 individuals in which reported evidence of infection depends on work-related factors as well as a variety of personal controls.ResultsThe following themes emerge from the analysis. First, a range of work-related factors are significant sources of variation in COVID-19 infection as indicated by self-reports of medical diagnosis or symptoms. This includes evidence about workplace types, consultation about safety and union memb…

External parameters contribution in domestic load forecasting using neural network

2015

Domestic demand prediction is very important for home energy management system and also for peak reduction in the power system network. In this work, for precise prediction of power demand, external parameters, such as temperature and solar radiation, are considered and included in the prediction model for improving prediction performance. Power prediction models for coming hours' power demand estimation are built using neural network based on hourly power consumptions data with / without ambient temperature data and global solar irradiation (GSI) data respectively. In this work, a typical Southern Norwegian household demand has been considered. As a result, both ambient temperature and GSI…