Search results

1 – 10 of over 1000
Article
Publication date: 11 May 2020

Mengjie Hua, Shuo Yang, Quan Xu, Mo Chen, Huagan Wu and Bocheng Bao

The purpose of this paper is to develop two types of simple jerk circuits and to carry out their dynamical analyses using a unified mathematical model.

Abstract

Purpose

The purpose of this paper is to develop two types of simple jerk circuits and to carry out their dynamical analyses using a unified mathematical model.

Design/methodology/approach

Two types of simple jerk circuits only involve a nonlinear resistive feedback channel composited by a nonlinear device and an inverter. The nonlinear device is implemented through parallelly connecting two diode-switch-based series branches. According to the classifications of switch states and circuit types, a unified mathematical model is established for these two types of simple jerk circuits, and the origin symmetry and scale proportionality along with the origin equilibrium stability are thereby discussed. The coexisting bifurcation behaviors in the two types of simple jerk systems are revealed by bifurcation plots, and the origin symmetry and scale proportionality are effectively demonstrated by phase plots and attraction basins. Moreover, hardware experimental measurements are performed, from which the captured results well validate the numerical simulations.

Findings

Two types of simple jerk circuits are unified through parallelly connecting two diode-switch-based series branches and a unified mathematical model with six kinds of nonlinearities is established. Especially, the origin symmetry and scale proportionality for the two types of simple jerk systems are discussed quantitatively. These jerk circuits are all simple and inexpensive, easy to be physically implemented, which are helpful to explore chaos-based engineering applications.

Originality/value

Unlike previous works, the significant values are that through unifying these two types of simple jerk systems, a unified mathematical model with six kinds of nonlinearities is established, upon which symmetrically scaled coexisting behaviors are numerically disclosed and experimentally demonstrated.

Details

Circuit World, vol. 47 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 March 2006

Y. Zhang

Seeks to study the dependence of the shear strength of a fluid on the fluid pressure and the bulk fluid temperature, respectively, theoretically for given bulk fluid temperatures…

Abstract

Purpose

Seeks to study the dependence of the shear strength of a fluid on the fluid pressure and the bulk fluid temperature, respectively, theoretically for given bulk fluid temperatures and fluid pressures in the whole ranges of fluid pressure and bulk fluid temperature.

Design/methodology/approach

The analyses are, respectively, carried out with emphasis on the dependence of the shear strength of a fluid in liquid state, i.e. at low pressures on the fluid pressure and the bulk fluid temperature for given bulk fluid temperatures and fluid pressures based on the theory of the compression of the fluid by the pressurization of the fluid.

Findings

The fluid shear strength versus fluid pressure curve in the whole range of fluid pressure and the fluid shear strength versus bulk fluid temperature curve in the whole range of bulk fluid temperature, respectively, for a given bulk fluid temperature and a given fluid pressure are obtained. It is shown by this fluid shear strength versus fluid pressure curve that, for a given bulk fluid temperature, when the fluid is in liquid state, i.e. at low pressures, the value of the shear strength of the fluid is insensitive to the variation of the pressure of the fluid and is low: when the fluid is in solidification state, i.e. at medium and high but not extremely high pressures, the value of the shear strength of the fluid is the most sensitive to the variation of the pressure of the fluid and is very approximately linearly increased with the increase of the pressure of the fluid; when the fluid is in high solidification state, i.e. at extremely high pressures, the value of the shear strength of the fluid is insensitive to the variation of the pressure of the fluid and is the highest, i.e. approaches the value of the shear strength of the fluid in solid state.

Originality/value

Extends one's knowledge of the shear strength of a fluid in the while ranges of pressure and temperature.

Details

Industrial Lubrication and Tribology, vol. 58 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 12 October 2015

Marie Björk and Gunilla Pettersson-Berggren

The purpose of this paper is to investigate what might be relevant to younger children’s understanding of a number line and how teaching can be designed according to variation…

Abstract

Purpose

The purpose of this paper is to investigate what might be relevant to younger children’s understanding of a number line and how teaching can be designed according to variation theory to give pupils the opportunity to develop an understanding of the number line as a tool for mathematical thinking.

Design/methodology/approach

A Learning Study was conducted by mathematics teachers at Sjöstadsskolan in Stockholm. Variation theory was used as a theory of learning. In order to use the number line as a tool in mathematical thinking, pupils have to discern what is important for this form of representation of the numeral system. Critical aspects from other studies with similar learning objects have been taken into consideration for pre-test design. These aspects supplemented and enhanced the analysis of the results and the results were consistent with earlier learning studies’.

Findings

Four critical features, for younger pupils’ understanding of how the number line can be constructed, have been established in the study: the number line can have a different range (e.g. 0-20 or 30-60), correlation between the distance and value, two reference points are needed to place a third number and determine the scale, and the correlation between a part and whole.

Originality/value

Learning Study is emphasized as a powerful and structured model for teacher driven research aiming to develop the praxis. The use of experiences and results from other studies is recommended.

Details

International Journal for Lesson and Learning Studies, vol. 4 no. 4
Type: Research Article
ISSN: 2046-8253

Keywords

Book part
Publication date: 10 June 2009

Robert M. Wiseman

Management and especially strategy research rely heavily on the use of ratios to measure a variety of firm, industry, and societal characteristics. Most often, these ratios are…

Abstract

Management and especially strategy research rely heavily on the use of ratios to measure a variety of firm, industry, and societal characteristics. Most often, these ratios are created simply to control for size effects (i.e., scaling) emanating from differences in the size of firms, industries, populations, or national economies on the variables of interest. In addition, ratios may also hold theoretical meaning apart from that of their components. Despite the popularity of ratios and regardless of their purpose, the use of ratios is not without controversy. In particular, several studies have demonstrated that the use of ratio measures in correlations and multiple regressions can exaggerate relations of interest leading to biased and unstable results. In this chapter, I review the debate surrounding the use of ratio measures, discuss the problems for estimation and inference that are likely to arise when ratios are used in statistical estimation, and provide alternatives to the use of ratio variables that still satisfy the purpose for which ratio measures are often created.

Details

Research Methodology in Strategy and Management
Type: Book
ISBN: 978-1-84855-159-6

Article
Publication date: 1 March 1998

Ralph Henham

The aim of this article is to examine those philosophical and structural factors which have been responsible for shaping sentencing policy for economic crime in the UK and to…

Abstract

The aim of this article is to examine those philosophical and structural factors which have been responsible for shaping sentencing policy for economic crime in the UK and to analyse some key decisions of the Court of Appeal (Criminal Division) in this area.

Details

Journal of Financial Crime, vol. 6 no. 1
Type: Research Article
ISSN: 1359-0790

Article
Publication date: 7 March 2023

Amita Majumder and Chayanika Mitra

Many aspects of well-being depend critically on individual-level expenditure and consumption. The Millennium Development Goals include the promotion of gender equality and the…

Abstract

Purpose

Many aspects of well-being depend critically on individual-level expenditure and consumption. The Millennium Development Goals include the promotion of gender equality and the empowerment of women, which partly have to do with women’s access to resources within households. Many important questions in labour, public and development economics also hinge on the intra-household distribution of resources. This paper aims to estimate the resource shares within a household in the rural and urban sectors of West Bengal through a collective household model, where each household member has a specific utility function. The sharing rule parameters, that determine the apportionment of resources between members within a household, are estimated in an intra-household collective framework. The analysis is based on a system of log-quadratic Engel curves estimated using the 68th round (2011–2012) household-level consumption expenditure data of the Indian National Sample Survey Office (NSSO) for rural and urban sectors separately for the state of West Bengal.

Design/methodology/approach

The sharing rule parameters (that determine the apportionment of resources between members) within a household are estimated in an intra-household collective framework as suggested by Dunbar et al. (2013). The analysis is based on a Quadratic Almost Ideal Demand System (QUAIDS) estimated using the 68th round (2011–2012) household-level consumption expenditure data of the Indian NSSO.

Findings

In this paper, the authors estimate the sharing rule of total household expenditure between couples in a household in the state of West Bengal. They use a modified version of the QUAIDS and the 68th round (2011–2012) household-level consumer expenditure data provided by the NSSO. From the exercise, it emerges that on an average, the resource shares between husband and wife in a household is about 66:34% in the rural sector and about 60:40% in the urban sector. Based on a classification of households by the distribution of resource shares, where higher resource share for the husband is classified as “Husband dominated” and the reverse as “Wife dominated”, the percentage of “Husband dominated” households is much more in both sectors. This unequal distribution of resources may have far-reaching consequences on allocation of expenditure on the children of the household. The authors leave this exercise as a future project.

Originality/value

This paper is an attempt to estimate the sharing rule for households using NSSO consumption expenditure data. This paper also highlights the intra household unequal resource allocation through the sharing rule. They use a modified version of the QUAIDS and the 68th round (2011–2012) household-level consumer expenditure data provided by the NSSO. From the exercise, it emerges that on an average, the resource shares between husband and wife in a household is about 66:34% in the rural sector and about 60:40% in the urban sector. Based on a classification of households by the distribution of resource shares, where higher resource share for the husband is classified as “Husband dominated” and the reverse as “Wife dominated”, the percentage of “Husband dominated” households is much more in both sectors. This unequal distribution of resources may have far-reaching consequences on allocation of expenditure on the children of the household. The authors leave this exercise as a future project.

Details

Indian Growth and Development Review, vol. 16 no. 1
Type: Research Article
ISSN: 1753-8254

Keywords

Open Access
Article
Publication date: 15 January 2024

Sol Garrido

This study aims to introduce an alternative model, “volatility, uncertainty, complexity and ambiguity (VUCA), Virtue and Vice” (3V’s), to unleash leadership skills, promote…

487

Abstract

Purpose

This study aims to introduce an alternative model, “volatility, uncertainty, complexity and ambiguity (VUCA), Virtue and Vice” (3V’s), to unleash leadership skills, promote organisational collaborative change and impact sales performance during an unprecedented crisis.

Design/methodology/approach

The methodology outlines action research based on the 3V’s model and its application in an international business-to-business sales organisation during Covid-19. It explores alternative paths informed by play-at-work and Plato’s philosophy applied to work-based-learning. Each action/iteration adds to the model, which becomes more likely appropriate for various situations.

Findings

The 3V’s boosted change implementation and improved sales performance. The 3V’s conceptualised an invitation to immerse oneself in the constant “river of change” (VUCA) and a means of understanding the role of leadership in navigating this change by embracing simple rules: searching for justice (Virtue) and overcoming the barrier of public opinion (Vice).

Research limitations/implications

The 3V’s model is grounded in leadership literature and a sole application, providing real international data relevant to organisations and leaders. This has yet to be evaluated further.

Practical implications

3V’s can enhance the understanding of a leading collaborative change and re-frame team dynamics in post-pandemic times for the broader public.

Social implications

The approach advocated is a practice of “swimming alongside the team”, which should enable empowerment and collaboration rather than a top-down direction. Focussing on leaders who are moral people, this approach becomes a differentiator in a digital world.

Originality/value

This study examines Plato’s philosophy, play-at-work and other leadership theories in a model which prepares organisations to respond to crisis by providing the ability to reflect on human aspects and straightforward, transferable skills.

Details

Journal of Work-Applied Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2205-2062

Keywords

Content available

Abstract

Details

History of Education Review, vol. 45 no. 2
Type: Research Article
ISSN: 0819-8691

Keywords

Article
Publication date: 4 September 2017

Fanny Barsics, Rudy Caparros Megido, Yves Brostaux, Catherine Barsics, Christophe Blecker, Eric Haubruge and Frédéric Francis

Broader acceptance of entomophagy (i.e. human consumption of insects) will depend on factors that impact consumers’ perceptions of edible insects. The purpose of this paper is to…

1969

Abstract

Purpose

Broader acceptance of entomophagy (i.e. human consumption of insects) will depend on factors that impact consumers’ perceptions of edible insects. The purpose of this paper is to examine how a broad-based information session would affect consumers’ perceptions and attitudes about an edible insect product.

Design/methodology/approach

During a taste testing session, preceded or followed by an information session about entomophagy, participants rated the organoleptic characteristics of two bread samples on nine-point hedonic scales. The two bread samples were identical, though one was faux-labelled as containing an insect product.

Findings

Generalised linear model (GLM) analysis showed effects of gender, information session exposure, entomophagy familiarity, and entomophagy experience on participants’ ratings of the samples. Wilcoxon-Mann-Whitney ranked sum tests showed that appearance, flavour, and overall liking were significantly better rated for the bread sample labelled as insect free by participants who attended the presentation a priori. Potential ways to improve information content and delivery in favour of encouraging dietary shifts are discussed.

Practical implications

This study shows that information about insect-based products could change consumers’ perceptions of such products. The results provide clues regarding how the food industry can adapt communication for target audiences.

Originality/value

Actual edible insect products were not used in this study. Paradoxically, it is the first to show the impact of an information session on the acceptability of edible insect products, by revealing participants’ perceptual expectations.

Details

British Food Journal, vol. 119 no. 9
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 23 August 2022

Miroslav Zizka and Eva Stichhauerova

This study aims to determine how much company participation in a type of cluster affects its economic performance.

Abstract

Purpose

This study aims to determine how much company participation in a type of cluster affects its economic performance.

Design/methodology/approach

This study includes companies operating in seven industries (automotive, engineering, textiles, information technology (IT) services, furniture, packaging and nanotechnology) in the Czech Republic. The companies are divided into three groups: members of institutionalized cluster, operating in the same region (natural clusters) and operating in other regions. Data envelopment window analysis is used to measure their performance for 2009–2019.

Findings

Results show that the effect of clustering differs among industries. Companies in three industries (automotive, engineering, nanotechnology) reveal a positive impact of the cluster initiative on performance growth. Two industries (textile, packaging) with companies operating in a natural cluster show better performance than those in an institutionalized cluster. Moreover, the IT services and the furniture industries show no positive effect of clustering on corporate performance.

Research limitations/implications

This research includes 686 companies from seven industries and monitored for 11 years. On the one hand, the sample includes a relatively high number of companies overall; but on the other hand, the sample is relatively small, especially for nonclustered companies. The reason is the lack of available financial statements for small companies.

Practical implications

From the perspective of practical cluster policy, the authors can recommend that monitoring the performance of member companies in clusters must be one of the criteria for evaluating the success of a cluster, such as cluster initiatives.

Originality/value

This study distinguishes between long-standing natural clusters in a given industry and institutionalized ones that have emerged because of a top-down initiative. An original database is created for clustered and nonclustered companies in seven industries, covering the entire Czech Republic.

Details

Competitiveness Review: An International Business Journal , vol. 33 no. 6
Type: Research Article
ISSN: 1059-5422

Keywords

1 – 10 of over 1000