Search results for "equation"
showing 10 items of 4219 documents
THE MINIMIZING TOTAL VARIATION FLOW WITH MEASURE INITIAL CONDITIONS
2004
In this paper we obtain existence and uniqueness of solutions for the Cauchy problem for the minimizing total variation flow when the initial condition is a Radon measure in ℝN. We study limit solutions obtained by weakly approximating the initial measure μ by functions in L1(ℝN). We are able to characterize limit solutions when the initial condition μ=h+μs, where h∈L1(ℝN)∩L∞(ℝN), and μs=αℋk⌊ S,α≥0,k is an integer and S is a k-dimensional manifold with bounded curvatures. In case k<N-1 we prove that the singular part of the solution does not move, it remains equal to μs for all t≥0. In particular, u(t)=δ0 when u(0)=δ0. In case k=N-1 we prove that the singular part of the limit solution …
Revista electrónica de investigación y evaluación educativa
2010
Este trabajo tiene el propósito de mostrar el uso de la metodología de Modelos de Ecuaciones Estructurales (SEM) para validar la estructura conceptual de cuestionarios de contexto que se utilizan en los estudios nacionales e internacionales para evaluar el logro educativo de los escolares. Desgraciadamente, los organismos evaluadores no destinan los mismos recursos técnicos a los cuestionarios de contexto que a las pruebas de aprendizaje, por lo que rara vez los primeros son sujetos a estudios de validez. Para mostrar el uso de la metodología SEM, se seleccionó el cuestionario dirigido a alumnos que utilizó el Instituto Nacional para la Evaluación de la Educación (INEE) para conocer los fac…
Interactions between contingency, organizational IT factors, and ERP success
2009
PurposeThe purpose of this paper is to examine the impact of some organizational information technology (IT) factors (i.e. IT assets, employees' IT skills, IT resources, and satisfaction with legacy IT systems) and their interacting effects with two contingency factors (i.e. organization's size and structure) on enterprise resource planning (ERP) system success.Design/methodology/approachSurveys were conducted in two European countries. Respondents came from diverse, private, and industrial organizations. Relevant hypotheses were developed and tested using a structural equation modeling technique.FindingsThe analysis supported – partially or fully – six of the eight hypotheses formulated. F…
Deducing the USLE mathematical structure by dimensional analysis and self-similarity theory
2010
The Universal Soil Loss Equation (USLE) was originally deduced by a statistical analysis of a large data set of soil loss measurements. The multiplicative structure of the model has been criticised due to the considerable interdependence between the variables. Using the soil erosion representative variables and the reference condition adopted in the USLE, the aim of this paper was to apply dimensional analysis and self-similarity theory to deduce the functional relationship among the selected variables. The analysis yielded a multiplicative equation, similar to the USLE. Therefore, this study suggested that the USLE has a logical structure with respect to the variables used to simulate the …
Investigating Some Construct Validity Threats to TALIS 2018 Teacher Job Satisfaction Scale: Implications for Social Science Researchers and Practitio…
2020
The credibility of findings ensuing from cross-sectional survey research depends largely on the validity and reliability of the research instruments. Critical attention to the quality of such instruments will ensure logical and valid results. The purpose of this article is to provide evidence for two methodological issues observed that are potential threats to construct validity of widely used Teaching and Learning International Survey (TALIS) 2018 data on teacher job satisfaction scale (TJSS). The first issue concerns reverse recoding of some items necessary to obtain a coherence covariance between these items and other items on the same subscale. The second issue concerns the addition of …
Cluster Algorithm Integrated with Modification of Gaussian Elimination to Solve a System of Linear Equations
2020
The data accumulation and their inhomogeneous distribution lead to the issue of large and sparse systems solving in various fields: industrials, emergency management, etc. Complex structure in the data error creates additional risk to obtain an adequate solution. To facilitate problem-solving, we describe the technique that is based on intellectual division of data with following application of cluster algorithm and the modification of Gaussian elimination to different portions of data. In this paper, we present results of developed technique that was applied to samples of synthetic and real data. We compare them with outcomes of other algorithms (intelligence and classical) by using of num…
Two non-zero solutions for Sturm–Liouville equations with mixed boundary conditions
2019
Abstract In this paper, we establish the existence of two non-zero solutions for a mixed boundary value problem with the Sturm–Liouville equation. The approach is based on a recent two critical point theorem.
Bullying in Students Who Stutter: The Role of the Quality of the Student–Teacher Relationship and Student’s Social Status in the Peer Group
2020
Children who stutter are at risk of being excluded, rejected, or bullied at school because of their impairment. The aim of the current research is to assess the relationship between students and te...
Quasivarieties of Algebras
2001
This chapter plays a twofold role in the book. Firstly, the chapter surveys basic facts about quasivarieties of algebras. These facts are widely utilised in the subsequent chapters devoted to algebraizable logics. Secondly, the chapter shows how the methods initially elaborated for protoalgebraic sentential logics in the first part can be also applied in the area of equational logic. Most of the results presented in this chapter are proved by way of adapting the purely consequential methods of sentential logic to the needs of the (quasi) equational systems associated with quasivarieties of algebras.
Determinants of user behaviour and recommendation in social networks
2014
Purpose – The purpose of this paper is to analyse the determinants of social network use behaviour using Theory of Planned Behaviour (TPB) and Uses and Gratifications Theory. Design/methodology/approach – A quantitative study was carried out with data gathered by personal interview using a structured questionnaire. Relationships proposed in the theoretical model were estimated through structural equation models. In total, 811 users of social networks over 14 and residents in Spain were part of the sample. Findings – Results indicate that use attitude and the subjective norm, both TPB variables, directly and significantly influence social network loyalty. Thus, network loyalty can be achiev…