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1 – 10 of over 7000Changsheng Wang, Xiao Han, Caixia Yang, Xiangkui Zhang and Wenbin Hou
Numerous finite elements are proposed based on analytical solutions. However, it is difficult to find the solutions for complicated governing equations. This paper aims to present…
Abstract
Purpose
Numerous finite elements are proposed based on analytical solutions. However, it is difficult to find the solutions for complicated governing equations. This paper aims to present a novel formulation in the framework of assumed stress quasi-conforming method for the static and free vibration analysis of anisotropic and symmetric laminated plates.
Design/methodology/approach
Firstly, an initial stress approximation ruled by 17 parameters, which satisfies the equilibrium equations is derived to improve the performance of the constructed element. Then the stress matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the Timoshenko’s laminated composite beam functions are adopted as boundary string-net functions for strain integration.
Findings
Several numerical examples are presented to show the performance of the new element, and the results obtained are compared with other available ones. Numerical results have proved that the new element is free from shear locking and possesses high accuracy for the analysis of anisotropic and symmetric laminated plates.
Originality/value
This paper proposes a new QC element for the static and free vibration analysis of anisotropic and symmetric laminated plates. In contrast with the complicated analytical solutions of the equilibrium equations, an initial stress approximation ruled by 17 parameters is adopted here. The Timoshenkos laminated composite beam functions are introduced as boundary string-net functions for strain integration. Numerical results demonstrate the new element is free from shear locking and possesses high accuracy for the analysis of anisotropic and symmetric laminated plates.
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The purpose of this paper is to present a general formulation of the quadrature element method (QEM). The method is then used to investigate the free vibration of functionally…
Abstract
Purpose
The purpose of this paper is to present a general formulation of the quadrature element method (QEM). The method is then used to investigate the free vibration of functionally graded (FG) beams with general boundary conditions and different variations of material properties.
Design/methodology/approach
The quadrature elements with arbitrary number of nodes and nodal distributions are established on the basis of two types of FG Timoshenko beam theories. One called TBT-1 takes the cross-sectional rotation as the unknown function and the other called TBT-2 uses the transverse shear strain as the unknown function. Explicit formulas are provided via the help of the differential quadrature (DQ) rule and thus the elements can be implemented adaptively with ease.
Findings
The suitability and computational efficiency of the proposed quadrature elements for the vibration analysis of FG beams are demonstrated. The convergence rate of the proposed method is high. The elements are shear-locking free and can yield accurate solutions with a small number of nodes for both thin and moderately thick beams. The performance of the element based on TBT-1 is better than the one based on TBT-2.
Originality/value
The present QEM is different from the existing one which exclusively uses Gauss–Lobatto–Legendre (GLL) nodes and GLL quadrature and thus is more general. The element nodes can be either the same or different from the integration points, making the selection of element nodes more flexible. Presented data are accurate and may be a reference for other researchers to develop new numerical methods. The QEM may be also useful in multi-scale modeling and in the analysis of civil infrastructures.
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Neus (Snowy) Evans, Hilary Inwood, Beth Christie and Eva Ärlemalm-Hagsér
The purpose of this paper is to undertake a cross-comparative inquiry into Education for Sustainable Development (ESD) related to governance, initiatives and practices in initial…
Abstract
Purpose
The purpose of this paper is to undertake a cross-comparative inquiry into Education for Sustainable Development (ESD) related to governance, initiatives and practices in initial teacher education (ITE) across four countries with very different contexts – Sweden, Scotland, Canada and Australia. It provides insights into issues arising internationally, implications for ESD in ITE and offers learnings for other countries and contexts.
Design/methodology/approach
A cross-comparative study design with overarching themes and within-case descriptions was applied to consider, compare and contrast governance characteristics, initiatives and practices from each context.
Findings
The approaches to governance, initiatives and practices that each country adopts are unique yet similar, and all four countries have included ESD in ITE to some extent. Comparing and contrasting approaches has revealed learnings focussed on ESD in relation to governance and regulation, practices and leadership.
Research limitations/implications
Making comparisons between different contexts is difficult and uncertain and often misses the richness and nuances of the individual sites under study. However, it remains an important endeavour as the challenges of embedding ESD in ITE will be better understood and overcome if countries can learn from one another.
Originality/value
Scrutinising different approaches is valuable for broadening views about possibilities and understanding how policies and initiatives translate in practice.
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Manuela Gonçalves Barros, Marcelo Botelho da Costa Moraes, Alexandre Pereira Salgado Junior and Marco Antonio Alves de Souza Junior
The purpose of this paper is to evaluate the efficiency in financial intermediation and the cost efficiency in banking service of credit unions in Brazil, based on essentially…
Abstract
Purpose
The purpose of this paper is to evaluate the efficiency in financial intermediation and the cost efficiency in banking service of credit unions in Brazil, based on essentially accounting variables, and to analyze the temporal evolution of the efficiency of these cooperatives.
Design/methodology/approach
With a sample of 315 cooperatives over the period from 2007 to 2014, this research uses a two-stage process: application of regression models with panel data to verify which variables are related to the defined outputs, with the reduction of 31 variables to 8 variables in both models; and application of the data envelopment analysis method to obtain an analysis of credit unions’ efficiency.
Findings
The results demonstrate a high level of efficiency in financial intermediation, with low variation over time, associated with a low efficiency in the banking service, in which few cooperatives have remained efficient over time. In addition, the cooperatives with highest efficiency in financial intermediation were also the most efficient in providing services.
Research limitations/implications
This research has some limitations about the capacity of the proxies used to capture the real effect of the variables and assumptions of economic relations resulting in restrictions to generalize the results.
Practical implications
Cooperatives are usually analyzed under just one dimension. By separating the analysis into financial intermediation and banking services, cooperatives that are more efficient in each dimension can be identified, in addition to analyzing the evolution over time. The authors found that efficiency tends to be lower in banking services, and few cooperatives remain at the highest level of efficiency over time in both models.
Social implications
Credit unions provide an important service in the banking and credit market. Therefore, understanding its operation and the characteristics that influence its efficiency allows a better management of the cooperatives themselves and a greater understanding of this important segment of the financial market.
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Muhammad Ilyas, Rehman Uddin Mian and Affan Mian
Using a comprehensive sample from developed and emerging economies, this study aims to examine whether foreign institutional investors (FIIs) enhance the value of excess cash by…
Abstract
Purpose
Using a comprehensive sample from developed and emerging economies, this study aims to examine whether foreign institutional investors (FIIs) enhance the value of excess cash by constraining the potential self-appropriating managerial propensity related to its inefficient utilization.
Design/methodology/approach
This study uses a large panel data set of firms from 32 non-US countries from 2007 to 2018. Using data from COMPUSTAT Global and S&P Capital IQ, this study uses ordinary least squares regression with year- and firm-fixed effects for the baseline analysis. In addition, two-stage least squares with instrumental variable regression and propensity score matching approaches were used to address the potential endogeneity.
Findings
This study shows that FIIs significantly increase the value of excess cash holdings. The authors also found that the positive impact of FIIs is more significant when investors come from common-law countries with better governance and investor protection. Furthermore, in countries and firms with weaker governance controls, the relationship between FIIs and the value of excess cash is stronger, consistent with the institutional monitoring hypothesis. Collectively, the findings imply that FIIs are advantageous to investees because they effectively promote the efficient deployment of corporate resources.
Practical implications
Collectively, the findings of this study imply that FIIs are advantageous to investees because they effectively promote the efficient deployment of corporate resources.
Originality/value
This study offers new evidence on how FIIs impact the value of excess cash in an international setting. In addition, it highlights the significance of the legal origin of institutional investors’ home country and the governance quality of host countries and investee firms in influencing the effect of foreign institutional monitoring on the value of excess cash.
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J.D. Costa, J.A.M. Ferreira and L.P. Borrego
Welded components are often subjected to variable amplitude service loads, increasing the uncertainty of fatigue life due to material strength, notch geometries, defect content…
Abstract
Purpose
Welded components are often subjected to variable amplitude service loads, increasing the uncertainty of fatigue life due to material strength, notch geometries, defect content and residual stresses. In the case of friction stir welding (FSW) of aluminium alloys no data were found available concerning fatigue behaviour under variable amplitude loading. The purpose of this paper is to determine the fatigue strength of friction stir welds in AA6082‐T6 under constant and variable amplitude loading and analyse the validity of Miner's rule for these specific welding conditions.
Design/methodology/approach
Fatigue tests were carried out in a servo‐hydraulic testing machine using a stress ratio of R=0. Typified Gassner amplitude spectra were considered, using four shape exponent values. Microhardness tests were performed to characterize the Vickers hardness profile in the vicinity of the weld area. Relatively to the base material (BM), the FSW process leads to a decrease of the static mechanical properties.
Findings
Detailed examination revealed a hardness decrease in the thermo‐mechanically affected zone and the nugget zone average hardness was found to be lower than the base alloy hardness. The comparison with data collected from the literature shows that FSW specimens present higher fatigue resistance than specimens welded by metal inert gas and tungsten inert gas processes. However, they still have lower fatigue lives than the BM. Using the equivalent stress calculated by Miner's rule, a good agreement was observed between constant and variable fatigue loading results. The characteristic curve obtained for friction stir welds is higher than the International Institute of Welding (IIW) fatigue class for fusion welds with full‐penetration both‐sided butt joints.
Originality/value
No data are available concerning fatigue behaviour under variable amplitude loading for friction stir welds of aluminium alloys. Furthermore, this paper analyses the fatigue strength of friction stir welds in AA6082‐T6 under constant and variable amplitude loading in order to verify the validity of Miner's rule for this specific welding process. A comparison between characteristic fatigue curves, using IIW fatigue classes (FAT), is also performed.
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The Sanitary Committee of a certain County Council, strong with the strength of recent creation, have lately been animated by a desire to distinguish themselves in some way, and…
Abstract
The Sanitary Committee of a certain County Council, strong with the strength of recent creation, have lately been animated by a desire to distinguish themselves in some way, and, proceeding along the lines of least resistance, they appear to have selected the Public Analyst as the most suitable object for attack. The charge against this unfortunate official was not that he is incompetent, or that he had been in any way negligent of his duties as prescribed by Act of Parliament, but simply and solely that he has the temerity to reside in London, which city is distant by a certain number of miles from the much favoured district controlled by the County Council aforesaid. The committee were favoured in their deliberations by the assistance of no less an authority than the “Principal” of a local “Technical School”;—and who could be more capable than he to express an opinion upon so simple a matter? This eminent exponent of scientific truths, after due and proper consideration, is reported to have delivered himself of the opinion that “scientifically it would be desirable that the analyst should reside in the district, as the delay occasioned by the sending of samples of water to London is liable to produce a misleading effect upon an analysis.” Apparently appalled by the contemplation of such possibilities, and strengthened by another expression of opinion to the effect that there were as “good men” in the district as in London, the committee resolved to recommend the County Council to determine the existing arrangement with the Public Analyst, and to appoint a “local analyst for all purposes.” Thus, the only objection which could be urged to the employment of a Public Analyst resident in London was the ridiculous one that the composition of a sample of water was likely to seriously alter during the period of its transit to London, and this contention becomes still more absurd when it is remembered that the examination of water samples is no part of the official duty of a Public Analyst. The employment of local scientific talent may be very proper when the object to be attained is simply the more or less imperfect instruction of the rising generation in the rudiments of what passes in this country for “technical education”; but the work of the Public Analyst is serious and responsible, and cannot be lightly undertaken by every person who may be acquainted with some of the uses of a test‐tube. The worthy members of this committee may find to their cost, as other committees have found before them, that persons possessing the requisite knowledge and experience are not necessarily indigenous to their district. Supposing that the County Council adopts the recommendation, the aspirations of the committee may even then be strangled in their infancy, as the Local Government Board will want to know all about the matter, and the committee will have to give serious and valid reasons in support of their case.
Muhammad Ilyas, Rehman Uddin Mian and Nabeel Safdar
This study examines the effects of foreign and domestic institutional investors on the value of excess cash holdings in the context of Pakistan where the institutional setting is…
Abstract
Purpose
This study examines the effects of foreign and domestic institutional investors on the value of excess cash holdings in the context of Pakistan where the institutional setting is broadly considered as non-friendly to outside shareholders due to family control.
Design/methodology/approach
A panel sample of 220 listed firms on the Pakistan Stock Exchange (PSX) was employed over the period 2007–2018. Data on institutional ownership are collected from the Standard & Poor’s (S&P) Capital IQ Public Ownership database, while the financial data are collected from Compustat Global. The study uses ordinary least squares (OLS) regression with year and firm fixed effects as the main econometric specification. Moreover, the application of models with alternative measures, high-dimensional fixed effects and two-stage least squares (2SLS) regression are also conducted for robustness.
Findings
Robust evidence was found that unlike domestic institutional investors, which do not influence the value of excess cash holdings, foreign institutional investors positively affect the contribution of excess cash holdings to firm value. The positive effect on excess cash holdings' value is mainly driven by foreign institutions domiciled in countries with strong governance and high investor protection. Moreover, this effect is stronger in firms that are less likely to have financial constraints.
Originality/value
This study provides novel evidence on the effect of institutional investors on the value of excess cash holdings in an emerging market like Pakistan. It also adds to the literature by revealing that the effect of different groups of institutional investors on the value of excess cash holdings is not homogenous.
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The Corporation of the City of London are about to appoint a Public Analyst, and by advertisement have invited applications for the post. It is obviously desirable that the person…
Abstract
The Corporation of the City of London are about to appoint a Public Analyst, and by advertisement have invited applications for the post. It is obviously desirable that the person appointed to this office should not only possess the usual professional qualifications, but that he should be a scientific man of high standing and of good repute, whose name would afford a guarantee of thoroughness and reliability in regard to the work entrusted to him, and whose opinion would carry weight and command respect. Far from being of a nature to attract a man of this stamp, the terms and conditions attaching to the office as set forth in the advertisement above referred to are such that no self‐respecting member of the analytical profession, and most certainly no leading member of it, could possibly accept them. It is simply pitiable that the Corporation of the City of London should offer terms, and make conditions in connection with them, which no scientific analyst could agree to without disgracing himself and degrading his profession. The offer of such terms, in fact, amounts to a gross insult to the whole body of members of that profession, and is excusable only—if excusable at all—on the score of utter ignorance as to the character of the work required to be done, and as to the nature of the qualifications and attainments of the scientific experts who are called upon to do it. In the analytical profession, as in every other profession, there are men who, under the pressure of necessity, are compelled to accept almost any remuneration that they can get, and several of these poorer, and therefore weaker, brethren will, of course, become candidates for the City appointment.
R. Branco, J.M. Silva, V. Infante, F. Antunes and F. Ferreira
Stress state has a major influence on different phenomena, namely those involving diffusion and plastic deformation (like crack closure and high‐temperature fatigue crack growth…
Abstract
Purpose
Stress state has a major influence on different phenomena, namely those involving diffusion and plastic deformation (like crack closure and high‐temperature fatigue crack growth, void formation or ductile fracture). The isolation of plane stress and plane strain states is crucial in fundamental studies of material behavior. The isolation of plane stress state is achieved with thin specimens, whilst the isolation of plane strain state is usually done increasing the thickness or introducing lateral grooves. The purpose of this paper is to propose a specimen geometry able to isolate the plane strain state, based on the standard M(T) geometry.
Design/methodology/approach
A numerical study was carried out aiming at obtaining a stress triaxiality parameter, h, as a function of different geometrical features of the specimen, such as the notch radius, notch depth and specimen thickness.
Findings
Results show that a pure plane strain state is achievable (i.e. 97 percent of specimen thickness has h>0.97) if a specimen with optimized geometrical features is used, which corresponds to a notch radius of 0.5 mm, a notch depth of 1 mm and a total specimen thickness of 12.56 mm.
Originality/value
This type of specimen geometry is a simple and efficient alternative to other common approaches used to obtain pure plain strain conditions for experimental purposes.
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