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1 – 10 of 159
Article
Publication date: 30 September 2013

Nataraj Chandrasekharan, Jaehyung Ju and Lonny Thompson

A three-dimensional finite element (FE) model is developed to design a vibrating bimorph piezoelectric cantilever beam with lead zirconate titanate (PZT-5H) for energy harvesting…

Abstract

Purpose

A three-dimensional finite element (FE) model is developed to design a vibrating bimorph piezoelectric cantilever beam with lead zirconate titanate (PZT-5H) for energy harvesting. The paper aims to discuss these issues.

Design/methodology/approach

A parametric study of electric power generated as a function of the dielectric constant, transverse piezoelectric strain constant, length and thickness of the piezoelectric material, is conducted for a time-harmonic surface pressure load. Transversely isotropic elastic and piezoelectric properties are assigned to the bimorph layers with brass chosen as the substrate material in the three-dimensional FE model. Using design of experiments, a study was conducted to determine the sensitivity of power with respect to the geometric and material variables.

Findings

The numerical analysis shows that a uniform decrease in thickness and length coverage of the piezoelectric layers results in a nonlinear reduction in power amplitude, which suggests optimal values. The piezoelectric strain coefficient, d31 and the thickness of PZT-5H, tp, are the most important design parameters to generate high electric energy for bimorph vibration harvesting device.

Originality/value

The work demonstrates that, through a sensitivity analysis, the electro-mechanical piezoelectric coupling coefficient (d31) and the thickness of the piezoelectric strips (tp) are the most important parameters which have a significant effect on power harvested.

Details

Multidiscipline Modeling in Materials and Structures, vol. 9 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 January 2014

Anna Meczynska, Roman Kmieciak, Anna Michna and Iwona Flajszok

This paper aims to propose and present a decision-making support method for poorly structured problems in schools, using the example of one of the most important and difficult…

Abstract

Purpose

This paper aims to propose and present a decision-making support method for poorly structured problems in schools, using the example of one of the most important and difficult decisions that principals face: terminating a teacher's employment.

Design/methodology/approach

A literature review was conducted, along with observations and interviews with 30 experienced principals, in order to identify decisions made by Polish principals. In order to sort non-programmable decisions according to their importance and difficulty, data were collected from 377 principals. Opinions from two groups, consisting of 22 and 25 experts, respectively, were collected in order to identify and order a set of criteria for making a specified non-programmable decision.

Findings

The four following areas of school activities were distinguished: finances, teaching and care, internal processes, and development of organisation. Within these categories, 126 decisions made by principals were identified, 96 of which were non-programmable. One of the most difficult and important non-programmable decisions was related to the termination of a teacher's employment. In order to support decisions regarding a teacher's dismissal, 44 criteria with different importance levels were identified.

Practical implications

Principals can use the method proposed in this paper, as it increases the rationality and objectivity of making a dismissal decision. The method can also be adapted for other difficult non-programmable decisions.

Originality/value

The expert opinion method might be useful for solving poorly structured problems in the management of educational institutions. As far as it can be ascertained, no previous empirical studies have identified and ranked the most important and difficult non-programmable decisions facing principals.

Details

Baltic Journal of Management, vol. 9 no. 1
Type: Research Article
ISSN: 1746-5265

Keywords

Article
Publication date: 31 December 2003

Jeanne K. Nel

Considers how the rights of children, protected under the Constitution of the Republic of South Africa and its Bill of Rights, can be reconciled with the effects of heavy fines…

Abstract

Considers how the rights of children, protected under the Constitution of the Republic of South Africa and its Bill of Rights, can be reconciled with the effects of heavy fines, asset forfeiture and confiscation orders on economic offenders. Clarifies the concepts of forfeiture and confiscation. Outlines the 1998 Prevention of Organised Crime Act (POCA) and considers its provisions in relation to the position of children and young people as innocent third parties in cases of civil and criminal asset forfeiture. Includes a short discussion of corresponding provisions in US law. Suggests that, as legislation currently does not specifically provide for children, the POCA should be amended by incorporating, mutatis mutandis, provisions from the Mediation in Certain Divorce Matters Act.

Details

Journal of Financial Crime, vol. 11 no. 2
Type: Research Article
ISSN: 1359-0790

Keywords

Book part
Publication date: 29 May 2009

Jeffrey T. LaFrance and Rulon D. Pope

This chapter presents the indirect preferences for all full rank Gorman and Lewbel demand systems. Each member in this class of demand models is a generalized quadratic…

Abstract

This chapter presents the indirect preferences for all full rank Gorman and Lewbel demand systems. Each member in this class of demand models is a generalized quadratic expenditure system (GQES). This representation allows applied researchers to choose a small number of price indices and a function of income to specify any exactly aggregable demand system, without the need to revisit the questions of integrability of the demand equations or the implied form and structure of indirect preferences. This characterization also allows for the calculation of exact welfare measures for consumers, either in the aggregate or for specific classes of individuals, and other valuations of interest to applied researchers.

Details

Quantifying Consumer Preferences
Type: Book
ISBN: 978-1-84855-313-2

Keywords

Article
Publication date: 1 January 1995

Marilyn E. Barnes

Libraries need to develop information processing systems for evaluation, budgeting, planning, and operations. Electronic spreadsheets lend themselves to a variety of applications…

Abstract

Libraries need to develop information processing systems for evaluation, budgeting, planning, and operations. Electronic spreadsheets lend themselves to a variety of applications, but are time‐consuming to create. A model template and macros that can be used in many different types of library data analysis have been developed here. The procedures demonstrated here can build an essential set of tools for meeting fundamental goals of administrative efficiency, effective use of library resources, staff motivation, and rational policy making.

Details

The Bottom Line, vol. 8 no. 1
Type: Research Article
ISSN: 0888-045X

Book part
Publication date: 16 November 2016

Veronika V. Eberharter

Based on representative longitudinal data (CNEF 1980–2013) the paper analyzes gender differences of the level and the determinants of earnings dynamics in the work life of…

Abstract

Based on representative longitudinal data (CNEF 1980–2013) the paper analyzes gender differences of the level and the determinants of earnings dynamics in the work life of different cohorts of employees in Germany, Great Britain, and the United States. Notwithstanding country differences concerning the existing welfare state regime constituting the institutional settings of the labor market, the educational system, and family role models, the empirical results show decreasing earnings mobility in the work history. The earnings level, educational attainment, family size, the occupational choice, the career stage, the birth cohort, and the macroeconomic fluctuations significantly influence earnings mobility. In the United States, earnings mobility is significantly lower and gender differences are less pronounced than in Germany and Great Britain. The gender gap of earnings mobility is less expressed for younger cohorts of German employees. The increase of the gender gap of earnings dynamics in the course of the work career indicates continuing heterogeneity of labor market behavior and outcome of women and men which contribute to persistent economic and social stratification.

Details

Inequality after the 20th Century: Papers from the Sixth ECINEQ Meeting
Type: Book
ISBN: 978-1-78560-993-0

Keywords

Book part
Publication date: 27 August 2016

Rafael Novella, Laura Ripani, Agustina Suaya, Luis Tejerina and Claudia Vazquez

Using longitudinal datasets from Chile and Nicaragua, we compare intragenerational earnings mobility over a decade for two economies with similar inequality levels but divergent…

Abstract

Using longitudinal datasets from Chile and Nicaragua, we compare intragenerational earnings mobility over a decade for two economies with similar inequality levels but divergent positions in equality of opportunities within the Latin American region. Our results suggest that earnings mobility, in terms of origin independence of individual ranking in the earnings distribution, is greater in Chile than in Nicaragua.

Details

Income Inequality Around the World
Type: Book
ISBN: 978-1-78560-943-5

Keywords

Book part
Publication date: 25 January 2023

John A. Bishop, Juan Gabriel Rodríguez and Lester A. Zeager

Economic mobility means different things to different people, but four major classes of mobility measures have been identified in the literature: positional, directional, mobility…

Abstract

Economic mobility means different things to different people, but four major classes of mobility measures have been identified in the literature: positional, directional, mobility as an equaliser of long-term earnings, and earnings risk (or flux). We illustrate some advantages of a multifaceted approach by comparing German and American earnings mobility using multiple indices from each of the four major classes for three panels of 10-year intervals. We anticipate and confirm that due to extensive differences in the German and American labour markets and in other social institutions that influence labour market outcomes, each country dominates in one facet of mobility but not in the others. Thus, a multifaceted approach contributes to a better understanding of the strengths and weakness of the two systems.

Book part
Publication date: 30 September 2014

Encarnación M. Parrado-Gallardo, Elena Bárcena-Martín and Luis J. Imedio-Olmedo

In this paper, we use the distributions of order statistics to define functions with the appropriate properties to represent social preferences regarding income distributions…

Abstract

In this paper, we use the distributions of order statistics to define functions with the appropriate properties to represent social preferences regarding income distributions. Following the approach of Yaari (1987, 1988), this allows constructing a set of social welfare functions from which the corresponding inequality indices are derived. The obtained measures incorporate diverse normative criteria, with different degrees of preference for equality. The generalized Gini coefficients and the family of indices proposed by Aaberge (2000) are obtained as particular cases. This approach allows interpreting each inequality measure in terms of the statistics computed from a randomly selected sample and the identification of unbiased estimators of the Social Welfare Functions. It also shows that each of the families of inequality indices are obtained from the moments of the order statistics and, therefore, each of the families characterizes any income distribution with finite mean. This characterization is very useful in the case of distributions with heavy tail and pronounced positive skew that shows only a few potential moments.

Details

Economic Well-Being and Inequality: Papers from the Fifth ECINEQ Meeting
Type: Book
ISBN: 978-1-78350-556-2

Keywords

Book part
Publication date: 30 September 2014

Carsten Schröder

When individual or household incomes are collected for administrative or scientific surveys, the accounting period is sometimes a month, sometimes a quarter, and sometimes a year…

Abstract

When individual or household incomes are collected for administrative or scientific surveys, the accounting period is sometimes a month, sometimes a quarter, and sometimes a year. The accounting period likely affects the shape of the income distribution and the level of measured inequality. The present study systematically explores the sensitivity of inter-temporal and inter-regional inequality comparisons to the length of the accounting period.

Details

Economic Well-Being and Inequality: Papers from the Fifth ECINEQ Meeting
Type: Book
ISBN: 978-1-78350-556-2

Keywords

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