Search results for " Methodology"
showing 10 items of 575 documents
The role of thermal contribution in the design of AA2024 friction stir welded butt and lap joints: mechanical properties and energy demand
2022
Although in recent times the use of solid-state welding processes as friction stir welding (FSW) has become increasingly widespread, for some joint morphologies, as lap joints, there are still signifcantly less data available on both process parameters optimization and energy consumption. In the present paper, the authors investigated the possibility of enhancing the joint quality in two diferent confgurations, i.e. lap and butt joints, taking into account specifc thermal contribution (STC) conferred to the weld. Strength, micro-hardness and microstructure were evaluated on the produced AA2024 aluminum alloys butt and lap joints. The surface response method (RSM) was used to investigate the…
Stimulating teachers’ participation in lifelong training programs
2021
In this paper we will present the main ways to stimulate teacher participation in lifelong education programs, we have conducted during a POCU project, implemented between April 11, 2018 and December 10, 2020. The purpose of this research approach was to demonstrate the role of providing incentives to teachers who participate in continuing education programs. The study started from the general hypothesis that providing the opportunity to obtain some types of incentives contributes to motivating teachers’ participation in continuing education programs, as well as to obtaining very good results in the evaluation process. The research methods used to carry out the research approach were: the s…
Objectives and methodology: Guidelines of the Italian Society for Haemostasis and Thrombosis (SISET).
2009
A current goal of the Italian Society for Thrombosis and Haemostasis (SISET) is the production of guidelines for clinical conditions related to haemostasis and thrombosis. In 2006, the Executive Committee of SISET adopted a new program for the production of methodologically and scientifically sound guidelines aimed at both addressing clinical practice and stimulating new research. The first major step for this program was to train methodologists to manage working groups that compose the guidelines, and to create a reference document that describes the development of the program. The aim of the present paper is to report a short version of this methodological document, for those who wish to …
Determination of Students’ Satisfaction Regarding Extracurricular Activities Conducted in The University. Comparative Study Romania-Germany
2014
Abstract The goal of this paper is to determine students’ satisfaction related to extracurricular activities in the field of vocational training, to identify possible problems and potential improvements. The research was conducted using quantitative and qualitative research methodology, various secondary sources, and the data were collected through the questionnaire method. The study constitutes the base of a compared management research Romania-Germany. Questioned have been 120 students from northern Germany, University of Applied Sciences Flensburg, University of Applied Sciences: Technology, Business and Design Wismar and University of Applied Sciences Kiel and 146 students from the cent…
IL-1 Superfamily Member (IL-1A, IL-1B and IL-18) Genetic Variants Influence Susceptibility and Clinical Course of Mediterranean Spotter Fever
2022
Mediterranean Spotted Fever (MSF) is one of the most common spotted fever Rickettsioses. Most cases of MSF follow a benign course, with a minority of cases being fatal. The severity of the infection depends on bacterial virulence, dose and host factors such as effective immune response and genetic background. Herein, we reported data on typing by competitive allele-specific PCR of functionally relevant polymorphisms of genes coding for MyD88 adapter-like (Mal/TIRAP) protein (rs8177374), interleukin(IL)-1 cluster (IL-1A rs1800587, IL-1B rs16944 and rs1143634) and IL-18 (rs187238), which might be crucial for an efficient immune response. The results enlighten the role that IL-1 gene cluster v…
The second-order analysis of marked spatio-temporal point processes, with an application to earthquake data
2016
To analyse interaction in marked spatio-temporal point processes (MSTPPs), we introduce marked (cross) second-order reduced moment measures and K-functions for general inhomogeneous second-order intensity reweighted stationary MSTPPs. These summary statistics, which allow us to quantify dependence between different mark categories of the points, are depending on the specific mark space and mark reference measure chosen. We also look closer at how the summary statistics reduce under assumptions such as the MSTPP being multivariate and/or stationary. A new test for independent marking is devised and unbiased minus-sampling estimators are derived for all statistics considered. In addition, we …
Modeling excess hazard with time--to--cure as a parameter
2019
Cure models have been widely developed to estimate the cure fraction when some subjects never experience the event of interest. However these models were rarely focused on the estimation of the time-to-cure i.e. the delay elapsed between the diagnosis and "the time from which cure is reached", an important indicator, for instance to address the question of access to insurance or loans for subjects with personal history of cancer. We propose a new excess hazard regression model that includes the time-to-cure as a covariate dependent parameter to be estimated. The model is written similarly to a Beta probability distribution function and is shown to be a particular case of the non-mixture cur…
Efficient Estimation of Nonlinear Finite Population Parameters Using Nonparametrics
2012
Currently, the high-precision estimation of nonlinear parameters such as Gini indices, low-income proportions or other measures of inequality is particularly crucial. In the present paper, we propose a general class of estimators for such parameters that take into account univariate auxiliary information assumed to be known for every unit in the population. Through a nonparametric model-assisted approach, we construct a unique system of survey weights that can be used to estimate any nonlinear parameter associated with any study variable of the survey, using a plug-in principle. Based on a rigorous functional approach and a linearization principle, the asymptotic variance of the proposed es…
Simulation Framework for Realistic Large-scale Individual-level Data Generation with an Application in the Health Domain
2020
We propose a framework for realistic data generation and simulation of complex systems and demonstrate its capabilities in the health domain. The main use cases of the framework are predicting the development of risk factors and disease occurrence, evaluating the impact of interventions and policy decisions, and statistical method development. We present the fundamentals of the framework using rigorous mathematical definitions. The framework supports calibration to a real population as well as various manipulations and data collection processes. The freely available open-source implementation in R embraces efficient data structures, parallel computing and fast random number generation which…
Scalable multiscale density estimation
2014
Although Bayesian density estimation using discrete mixtures has good performance in modest dimensions, there is a lack of statistical and computational scalability to high-dimensional multivariate cases. To combat the curse of dimensionality, it is necessary to assume the data are concentrated near a lower-dimensional subspace. However, Bayesian methods for learning this subspace along with the density of the data scale poorly computationally. To solve this problem, we propose an empirical Bayes approach, which estimates a multiscale dictionary using geometric multiresolution analysis in a first stage. We use this dictionary within a multiscale mixture model, which allows uncertainty in co…