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Article
Publication date: 1 March 1995

S. Oller, S. Botello, J. Miquel and E. Oñate

This paper shows a generalization of the classic isotropic plasticitytheory to be applied to orthotropic or anisotropic materials. This approachassumes the existence of a real…

Abstract

This paper shows a generalization of the classic isotropic plasticity theory to be applied to orthotropic or anisotropic materials. This approach assumes the existence of a real anisotropic space, and other fictitious isotropic space where a mapped fictitious problem is solved. Both spaces are related by means of a linear transformation using a fourth order transformation tensor that contains all the information concerning the real anisotropic material. The paper describes the basis of the spaces transformation proposed and the expressions of the resulting secant and tangent constitutive equations. Also details of the numerical integration of the constitutive equation are provided. Examples of application showing the good performance of the model for analysis of orthotropic materials and fibre‐reinforced composites are given.

Details

Engineering Computations, vol. 12 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 5 January 2010

J. Faleiro, S. Oller and A.H. Barbat

The purpose of this paper is to develop an improved analytical model for predicting the damage response of multi‐storey reinforced concrete frames modelled as an elastic…

1356

Abstract

Purpose

The purpose of this paper is to develop an improved analytical model for predicting the damage response of multi‐storey reinforced concrete frames modelled as an elastic beam‐column with two inelastic hinges at its ends.

Design/methodology/approach

The damage is evaluated in the hinges, using the concentrated damage concepts and a new member damage evaluation method for frame members, which leads to a meaningful global damage index of the structure. A numerical procedure for predicting the damage indices of the structures using matrix structural analysis, plastic theory and continuum damage model is also developed. The method is adequate for the prediction of the failure mechanisms.

Findings

Using the proposed framework numerical examples are finally included. From the obtained results, the advantages and limitation of the proposed model are observed.

Originality/value

The numeric model presented is useful to solve multi‐storey reinforced concrete frames using an inexpensive procedure that combines structural finite elements (beams) of low execution cost, with the moment‐curvature constitutive models deriving from classic stress‐strain ones. The proposed techniques give an inexpensive and reliability procedure to model the frame structures.

Details

Engineering Computations, vol. 27 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 22 May 2013

Richard Simpson and Stephen Crutchfield

Identification, implementation, and ongoing evaluation of scientifically supported and effective-practice methods are fundamental and crucial elements of an effective educational…

Abstract

Identification, implementation, and ongoing evaluation of scientifically supported and effective-practice methods are fundamental and crucial elements of an effective educational program for all children and youth, including learners with Autism Spectrum Disorders (ASD). To be sure, there is an unambiguous link between use of interventions and supports that have empirically supported merit and positive school and post-school outcomes. This chapter examines progress in the wide-scale adoption of evidence-based methods with learners with ASD. We also offer recommendations for advancing effective-practice initiatives and discuss trends and themes connected to effective-practice use with students with ASD.

Details

Evidence-Based Practices
Type: Book
ISBN: 978-1-78190-429-9

Article
Publication date: 24 August 2010

Sharif Moghaddam

The purpose of this paper is to report on a study to determine the possible effects of cultural schemata on Iranian students' test‐taking processes for cloze tests.

321

Abstract

Purpose

The purpose of this paper is to report on a study to determine the possible effects of cultural schemata on Iranian students' test‐taking processes for cloze tests.

Design/methodology/approach

A total of 116 students were selected as the participants. They were divided into two groups. One group completed a culturally familiar version of a cloze test, while the other did culturally unfamiliar version of the test. A number of unfamiliar words in the original cloze passage were changed to more familiar ones in the modified version. The participants were interviewed, and their retrospective protocols on the test‐taking processes and the information they could recall from the passage after they had completed the test were documented. The two groups' test‐taking activities were compared in terms of: demonstrating appropriate meaning making of the key terms while finding missing data and recalling, item performance, the amount of text information they had benefited from to fill in the blanks and the quantities and qualities of the final recalls.

Findings

The findings suggest that the students, who read the culturally familiar cloze text, generally understood the text to a greater extent which resulted in a higher score in comparison with those who read the original text. These results support the findings of some previous studies that cloze tests can measure higher order processing abilities.

Originality/value

The paper contributes to the literature on effects of cultural schemata on students' test‐taking processes for cloze tests and is original in that it is one of the few conducted in the Middle East.

Details

Education, Business and Society: Contemporary Middle Eastern Issues, vol. 3 no. 3
Type: Research Article
ISSN: 1753-7983

Keywords

Open Access
Article
Publication date: 8 April 2020

Isabel María Parra Oller, Salvador Cruz Rambaud and María del Carmen Valls Martínez

The main purpose of this paper is to determine the discount function which better fits the individuals' preferences through the empirical analysis of the different functions used…

3474

Abstract

Purpose

The main purpose of this paper is to determine the discount function which better fits the individuals' preferences through the empirical analysis of the different functions used in the field of intertemporal choice.

Design/methodology/approach

After an in-depth revision of the existing literature and unlike most studies which only focus on exponential and hyperbolic discounting, this manuscript compares the adjustment of data to six different discount functions. To do this, the analysis is based on the usual statistical methods, and the non-linear least squares regression, through the algorithm of Gauss-Newton, in order to estimate the models' parameters; finally, the AICc method is used to compare the significance of the six proposed models.

Findings

This paper shows that the so-called q-exponential function deformed by the amount is the model which better explains the individuals' preferences on both delayed gains and losses. To the extent of the authors' knowledge, this is the first time that a function different from the general hyperbola fits better to the individuals' preferences.

Originality/value

This paper contributes to the search of an alternative model able to explain the individual behavior in a more realistic way.

Details

European Journal of Management and Business Economics, vol. 30 no. 1
Type: Research Article
ISSN: 2444-8451

Keywords

Article
Publication date: 1 April 1988

E. Oñate, S. Oller, J. Oliver and J. Lubliner

A constitutive model based on classical plasticity theory for non‐linear analysis of concrete structures using finite elements is presented. The model uses the typical parameters…

Abstract

A constitutive model based on classical plasticity theory for non‐linear analysis of concrete structures using finite elements is presented. The model uses the typical parameters of non‐associated plasticity theory for frictional materials and a modified Mohr‐Coulomb yield surface is suggested. Onset and amount of cracking at a point are controlled by the values of the effective plastic strain and thus it can be studied by a posteriori postprocessing of numerical results. The accuracy and objectivity of the model is checked out with some examples of application.

Details

Engineering Computations, vol. 5 no. 4
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 20 April 2015

Sergiu Andrei Baetu, A H Barbat and Ioan Petru Ciongradi

The purpose of this paper is to investigate a dissipative reinforced concrete structural wall that can improve the behavior of a tall multi-storey building. The main objective is…

Abstract

Purpose

The purpose of this paper is to investigate a dissipative reinforced concrete structural wall that can improve the behavior of a tall multi-storey building. The main objective is to evaluate the damage of a dissipative wall in comparison with that of a solid wall.

Design/methodology/approach

In this paper, a comparative nonlinear dynamic analysis between a dissipative wall and a solid wall is performed by means of SAP2000 software and using a layer model. The solution to increase the seismic performance of a reinforced concrete structural wall is to create a slit zone with short connections. The short connections are introduced as a link element with multi-linear pivot hysteretic plasticity behavior. The behavior of these short connections is modeled using the finite element software ANSYS 12. In this study, the authors propose to evaluate the damage of reinforced concrete slit walls with short connections using seismic analysis.

Findings

Using the computational model created in the second section of the paper, a seismic analysis of a dissipative wall from a multi-storey building was done in the third section. From the results obtained, the advantages of the proposed model are observed.

Originality/value

A simple computational model was created that consume low processing resources and reduces processing time for a dynamic pushover analysis. Unlike other studies on slit walls with short connections, which are focussed mostly on the nonlinear dynamic behavior of the short connections, in this paper the authors take into consideration the whole structural system, wall and connections.

Details

Engineering Computations, vol. 32 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Open Access
Article
Publication date: 1 June 2016

Hilda Freimuth

This study analyzed 24 IELTS Task One (data explanation) prompts for task type, diagram type, subject matter, level of critical thought, and geographical references, in order to…

832

Abstract

This study analyzed 24 IELTS Task One (data explanation) prompts for task type, diagram type, subject matter, level of critical thought, and geographical references, in order to determine whether Emirati university students’ anecdotal claims of cultural bias on the IELTS academic writing exam (as experienced by the researcher in the past decade of teaching IELTS in the United Arab Emirates) are valid. The analysis found that the majority of the task types (88%) were non-process in nature (i.e. required the description of data in the form of a chart or graph, rather than the description of a process); 40% of the non-process prompts consisted of more than one diagram. The analysis revealed that 33% of the non-process prompts included bar graphs and 29% included line graphs. Pie charts appeared in 25% of the prompts and tables in only 17%. An Emirati student English preparatory program survey indicated the pie chart as the easiest to understand – a finding that may highlight a difference between the most commonly used IELTS prompt and the students’ prompt preference. A content analysis of topics found a high percentage (58%) of subject matter related to the social sciences, with 79% of the geographical references pertaining to Western contexts. An analysis of the amount of critical thought needed for graph interpretation revealed 52% of non-process prompts required some form of critical thought. The study therefore found that the cultural bias perceived by Emirati students has some validity, given the students’ socio-cultural and educational background.

Details

Learning and Teaching in Higher Education: Gulf Perspectives, vol. 13 no. 1
Type: Research Article
ISSN: 2077-5504

Article
Publication date: 3 August 2015

Sergiu Andrei Baetu, Alex H Barbat, Ioan Petru Ciongradi and Georgeta Baetu

The purpose of this paper is to investigate a reinforced concrete multi-storey building with dissipative structural walls. These walls can improve the behaviour of a tall…

Abstract

Purpose

The purpose of this paper is to investigate a reinforced concrete multi-storey building with dissipative structural walls. These walls can improve the behaviour of a tall multi-storey building. The authors’ main objective is to evaluate the damage of a building with dissipative walls in comparison with that of a building with solid walls.

Design/methodology/approach

In this paper, a comparative nonlinear dynamic analysis between a building with slit walls and then the same building with solid walls is performed by means of SAP2000 software and using a layer model. The solution to increase the seismic performance of a building with structural walls is to create slit zones with short connections in to the walls. The short connections are introduced as a link element with multi-linear pivot hysteretic plasticity behaviour. The hysteretic rules and parameters of these short connections were proposed by the authors and used in this analysis. In this study, the authors propose to evaluate the damage of a building with reinforced concrete slit walls with short connections using seismic analysis.

Findings

Using the computational model created by the authors for the slit wall, a seismic analysis of a multi-storey building with slit walls was done. From the results obtained, the advantages of the proposed model are observed.

Originality/value

Using a simple computational model, created by the authors, that consume low processing resources and reduces processing time, a nonlinear dynamic analysis on high-rise buildings was done. Unlike other studies on slit walls with short connections, which are focused mostly on the nonlinear dynamic behaviour of the short connections, in this paper the authors take into consideration the whole structural system, wall, connections and frames.

Details

Engineering Computations, vol. 32 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Open Access
Article
Publication date: 19 August 2022

Chengyun Liu, Kun Su and Miaomiao Zhang

This study aims to examine whether and how gender diversity on corporate boards is associated with voluntary nonfinancial disclosures, particularly water disclosures.

1149

Abstract

Purpose

This study aims to examine whether and how gender diversity on corporate boards is associated with voluntary nonfinancial disclosures, particularly water disclosures.

Design/methodology/approach

This study uses corporate water information disclosure data from Chinese listed firms between 2010 and 2018 to conduct regression analyses to examine the association between female directors and water information disclosure.

Findings

Empirical results show that female directors have a significantly positive association with corporate water information disclosure. Additionally, internal industry water sensitivity of firms moderates this significant relationship.

Originality/value

This study determined that female directors can promote not only water disclosure but also positive corporate water performance, reflecting the consistency of words and deeds of female directors in voluntary nonfinancial disclosures.

1 – 10 of 98