Search results for " modeling"

APROXIMACIÓN CONCEPTUAL Y PRÁCTICA A LOS MODELOS DE ECUACIONES ESTRUCTURALES

2017

En el presente trabajo se expone una aproximación conceptual y práctica a los Modelos de Ecuaciones Estructurales o Structural Equation Modeling (SEM). Los SEM están considerados entre las herramientas más potentes para el estudio de relaciones causales en datos no experimentales. Son una combinación del análisis factorial y la regresión múltiple y están compuestos por dos componentes: el modelo de medida y el modelo estructural. El modelo de medida describe la relación existente entre una serie de variables observables; mientras que en el modelo estructural se especifican las relaciones hipotetizadas entre las variables, es decir, se describen las relaciones entre las variables latentes me…

The Riverine Organism Drift Imager: A new technology to study organism drift in rivers and streams

2023

1. Drift or downstream dispersal is a fundamental process in the life cycle of many riverine organisms. In the face of rapidly declining freshwater biodiversity, there is a need to enhance our capacity to study the drift of riverine organisms, by overcoming the limitations of traditional labour-intensive sampling methods that result in data of low temporal and spatial resolution. 2. To address this need, we developed a new technology, the Riverine Organism Drift Imager (RODI), which combines in situ imaging with machine-learning classification. This technique expands on the traditional methodology by replacing the collection cup of a drift net with a camera system that continuously images r…

The Effect of the Perceived Utility of a Management Control System with a Broad Scope on the Use of Food Waste Information and on Financial and Non-F…

2020

The purpose of this study is to analyse the effect of the perceived utility of a management control system with a broad scope on the use of food waste information and on financial and non-financial performances in restaurants. To collect data, a questionnaire was administered in Brazilian restaurants. Data from 206 restaurants were analysed with structural equation modelling, which was performed with SmartPLS software. The results reveal that a management control system of broad scope, which includes non-financial information, is oriented towards the future, and contains an external and long-term focus, assists in the use of information on food waste. In addition, the use of information abo…

Diversity of Pharmacological Properties in Chinese and European Medicinal Plants: Cytotoxicity, Antiviral and Antitrypanosomal Screening of 82 Herbal…

2011

In an extensive screening, the antiviral, antitrypanosomal and anticancer properties of extracts from 82 plants used in traditional Chinese medicine and European phytomedicine were determined. Several promising plants that were highly effective against hepatitis B virus (HBV), bovine viral diarrhoea virus (BVDV)—a flavivirus used here as a surrogate in vitro model of hepatitis C virus, trypanosomes (Trypanosoma brucei brucei) and several cancer cell lines were identified. Six aqueous extracts from Celosia cristata, Ophioglossum vulgatum, Houttuynia cordata, Selaginella tamariscina, Alpinia galanga and Alpinia oxyphylla showed significant antiviral effects against BVDV without toxic effects …

A fuel cell model emulator, including temperature effects

2010

Experimental test on a fuel cell-supercapacitor hybrid power supply for a digital still camera

2009

Theoretical Game Approach for Mobile Users Resource Management in a Vehicular Fog Computing Environment

2018

Vehicular Cloud Computing (VCC) is envisioned as a promising approach to increase computation capabilities of vehicle devices for emerging resource-hungry mobile applications. In this paper, we introduce the new concept of Vehicular Fog Computing (VFC). The Fog Computing (FC) paradigm evolved and is employed to enhance the quality of cloud computing services by extending it to the edge of the network using one or more collaborative end-user clients or near-user edge devices. The VFC is similar to the VCC concept but uses vehicles resources located at the edge of the network in order to serve only local on-demand mobile applications. The aim of this paper is to resolve the problem of admissi…

In Silico Finite Element Modeling of Stress Distribution in Osteosynthesis after Pertrochanteric Fractures

2022

A stabilization method of pertrochanteric femur fractures is a contentious issue. Here, we assess the feasibility of rapid in silico 2D finite element modeling (FEM) to predict the distribution of stresses arising during the two most often used stabilization methods: gamma nail fixation (GNF) and dynamic hip screw (DHS). The modeling was based on standard pre-surgery radiographs of hip joints of 15 patients with pertrochanteric fractures of type A1, A2, and A3 according to the AO/OTA classification. The FEM showed that the stresses were similar for both GNF and DHS, with the medians ranging between 53–60 MPa and consistently lower for A1 than A3 fractures. Stresses also appeared in the fixa…

Genetic and Environmental Effects on Telomere Length and Lung Function : A Twin Study

2017

Background The purpose of the study was to estimate the heritability of leukocyte telomere length (LTL) and lung function and to examine whether LTL and lung function share genetic or environmental effects in common. Methods 386 monozygotic and dizygotic Finnish twin sisters (age 68.4±3.4 years) were included. Relative LTL was determined from peripheral blood DNA by qPCR. Lung function measures of FEV1, FVC, FEV1/FVC, and PEF were derived from spirometry. Genetic modeling was performed with MPlus statistical software. Results Univariate analysis revealed that in LTL, 62% (95% confidence interval 50–72) of the variance was explained by additive genetic and 38% (28–50) by unique environmental…

Uncertainty in urban stormwater quality modelling: The effect of acceptability threshold in the GLUE methodology

2007

Uncertainty analysis in integrated urban drainage modelling is of growing importance in the field of water quality. However, only few studies deal with uncertainty quantification in urban drainage modelling; furthermore, the few existing studies mainly focus on quantitative sewer flow modelling rather than uncertainty in water quality aspects. In this context, the generalised likelihood uncertainty estimation (GLUE) methodology was applied for the evaluation of the uncertainty of an integrated urban drainage model and some of its subjective hypotheses have been explored. More specifically, the influence of the subjective choice of the acceptability threshold has been detected in order to ga…