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Article
Publication date: 6 November 2017

Chunchen Xia, Zhixian Cao, Gareth Pender and Alistair Borthwick

The purpose of this paper is to present a fully conservative numerical algorithm for solving the coupled shallow water hydro-sediment-morphodynamic equations governing fluvial…

279

Abstract

Purpose

The purpose of this paper is to present a fully conservative numerical algorithm for solving the coupled shallow water hydro-sediment-morphodynamic equations governing fluvial processes, and also to clarify the performance of a conventional algorithm, which redistributes the variable water-sediment mixture density to the source terms of the governing equations and accordingly the hyperbolic operator is rendered similar to that of the conventional shallow water equations for clear water flows.

Design/methodology/approach

The coupled shallow water hydro-sediment-morphodynamic equations governing fluvial processes are arranged in full conservation form, and solved by a well-balanced weighted surface depth-gradient method along with a slope-limited centred scheme. The present algorithm is verified for a spectrum of test cases, which involve complex flows with shock waves and sediment transport processes with contact discontinuities over irregular topographies. The computational results of the conventional algorithm are compared with those of the present algorithm and evaluated by available referenced data.

Findings

The fully conservative numerical algorithm performs satisfactorily over the spectrum of test cases, and the conventional algorithm is confirmed to work similarly well.

Originality/value

A fully conservative numerical algorithm, without redistributing the water-sediment mixture density, is proposed for solving the coupled shallow water hydro-sediment-morphodynamic equations. It is clarified that the conventional algorithm, involving redistribution of the water-sediment mixture density, performs similarly well. Both algorithms are equally applicable to problems encountered in computational river modelling.

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Article
Publication date: 23 August 2019

Thomas Rowan and Mohammed Seaid

The purpose of this paper is to present a new numerical model for shallow water flows over heterogeneous sedimentary layers. It is already several years since the single-layered…

107

Abstract

Purpose

The purpose of this paper is to present a new numerical model for shallow water flows over heterogeneous sedimentary layers. It is already several years since the single-layered models have been used to model shallow water flows over erodible beds. Although such models present a real opportunity for shallow water flows over movable beds, this paper is the first to propose a multilayered solver for this class of flow problems.

Design/methodology/approach

Multilayered beds formed with different erodible soils are considered in this study. The governing equations consist of the well-established shallow water equations for the flow, a transport equation for the suspended sediments, an Exner-type equation for the bed load and a set of empirical equations for erosion and deposition terms. For the numerical solution of the coupled system, the authors consider a non-homogeneous Riemann solver equipped with interface-tracking tools to resolve discontinuous soil properties in the multilayered bed. The solver consists of a predictor stage for the discretization of gradient terms and a corrector stage for the treatment of source terms.

Findings

This paper reveals that modeling shallow water flows over multilayered sedimentary topography can be achieved by using a coupled system of partial differential equations governing sediment transport. The obtained results demonstrate that the proposed numerical model preserves the conservation property, and it provides accurate results, avoiding numerical oscillations and numerical dissipation in the approximated solutions.

Originality/value

A novel implementation of sediment handling is presented where both averaged and separate values for sediment species are used to ensure speed and precision in the simulations.

Details

Engineering Computations, vol. 37 no. 2
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 5 June 2007

R. Flin, Z. Pender, L. Wujec, V. Grant and E. Stewart

The aim of this study is to identify the dimensions used by police officers in Scotland to discriminate and categorise operational situations.

2037

Abstract

Purpose

The aim of this study is to identify the dimensions used by police officers in Scotland to discriminate and categorise operational situations.

Design/methodology/approach

This article was based on two studies: study 1 was a card‐sorting task: 23 officers categorised a set of 19 typical police operational situations, analysed using multi‐dimensional scaling; study 2 was a judgement task: 112 police officers rated 20 situations (19 from study1) in terms of amount of time to make a decision, risk to self, risk to others, familiarity and stress. Frequency data and correlations were calculated.

Findings

Study 1 results showed that the two main dimensions used to discriminate between situations were “familiarity” and “risk to the officer”. Study 2 found that most situations required a decision in less than three minutes. Rank and experience were related to familiarity but not to the other judgements. The situations requiring the fastest decisions were also judged to be of higher risk and more unfamiliar. Risks to self and to others were highly correlated, and higher risk situations were judged as more stressful.

Research limitations/implications

This preliminary study shows that knowledge elicitation techniques can be used to improve our understanding of police officers' knowledge and cognitive skills for operational policing.

Practical implications

Good situational judgements form the basis of effective operational decision‐making. Understanding how officers “read” situations and how this develops with expertise can provide valuable information for police training and critical incident management.

Originality/value

Police officers' cognitive skills have rarely been studied in relation to routine operational policing. This study is a first attempt to examine situational judgement skills.

Details

Policing: An International Journal of Police Strategies & Management, vol. 30 no. 2
Type: Research Article
ISSN: 1363-951X

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Article
Publication date: 1 January 1970

Min Chen

The purpose of this paper (including three studies) is to investigate the idea that individuals in an emergency situation experience significantly a higher level of emotional…

3152

Abstract

Purpose

The purpose of this paper (including three studies) is to investigate the idea that individuals in an emergency situation experience significantly a higher level of emotional activation, lower performance of task, and change in decision making, escaping behavior and conformity as compared to being in a non-emergency situation. It is also suggested that the level of emotional activation mediates the association between situation and the performance of task.

Design/methodology/approach

Study 1 was an experimental study with 43 university students and revealed that different situations induced different levels of emotional activation and they are positively and significantly related. Study 2 was a further exploration of study 1, in which 49 participants were asked to watch a recomposed video telling a reasonable story about escaping from the emergency and complete several tasks associated with two kinds of situations (non-emergency vs emergency). In study 3, 168 participants, randomly assigned to three groups, were asked to work on judgment tasks with different numbers of options.

Findings

Results revealed that individuals in an emergency situation experience significantly lower performance of task and higher conformity tendency than in a non-emergency situation. Also, the causal effect of the situation on the performance of task is mediated by the level of emotional activation. Moreover, results found that the performance of task is also a mediator between the level of emotional activation and conformity. Result showed that the number of choices is negatively related to conformity, and performance is a mediator between the number of choices and conformity.

Originality/value

This paper suggested that the level of emotional activation mediates the association between situation and the performance of task.

Details

Library Hi Tech, vol. 38 no. 3
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 16 March 2015

Anne Nassauer

The purpose of this paper is to connect sociology, criminology, and social psychology to identify specific factors that keep protests peaceful, discusses empirical examples of…

2420

Abstract

Purpose

The purpose of this paper is to connect sociology, criminology, and social psychology to identify specific factors that keep protests peaceful, discusses empirical examples of effective peacekeeping, and develops practical peacekeeping guidelines.

Design/methodology/approach

The analysis systematically compared 30 peaceful and violent protests in the USA and Germany to identify peaceful interaction routines and how they are disrupted. It employed a triangulation of visual and document data on each demonstration, analyzing over 1,000 documents in total. The paper relies on qualitative analysis based on the principles of process tracing.

Findings

Results show that specific interaction sequences and emotional dynamics can break peaceful interaction routines and trigger violence. Single interactions do not break these routines, but certain combinations do. Police forces and protesters need to avoid these interaction dynamics to keep protests peaceful. Communication between both sides and good police management are especially important.

Research limitations/implications

The paper highlights the need to examine the role of situational interactions and emotional dynamics for the emergence and avoidance of protest violence more closely.

Practical implications

Findings have implications for police practice and training and for officers’ and protesters’ safety.

Originality/value

Employing recent data and an interdisciplinary approach, the study systematically analyzes peacekeeping in protests, developing guidelines for protest organizers and police.

Details

Policing: An International Journal of Police Strategies & Management, vol. 38 no. 1
Type: Research Article
ISSN: 1363-951X

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Article
Publication date: 1 July 1998

Pender O. Gbenedio, Eric D. Benson and Eddy Omolehinwa

Traces the history of efforts to harmonize global accounting and presents a study analysing obstacles to it, using multidimensional scaling. Illustrates the environmental…

2236

Abstract

Traces the history of efforts to harmonize global accounting and presents a study analysing obstacles to it, using multidimensional scaling. Illustrates the environmental influences on global accounting, groups 37 factors obstructing harmonization into economic, social, political/legal and cultural groups; and assesses their impact in both developing and industrially developed countries (IDCs). Finds that political, economic and social variables create more difficulties for IDCs, but that cultural factors affect both groups equally. Displays the results graphically, discusses them further and calls for extended research to explore this “great challenge to the accounting profession”.

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Article
Publication date: 14 December 2022

Mohammad Rababa, Nahla Al-Ali and Ayat Shaman

This study aims to examine the recent literature on health-promoting behavior, health needs and associated factors among older adults.

196

Abstract

Purpose

This study aims to examine the recent literature on health-promoting behavior, health needs and associated factors among older adults.

Design/methodology/approach

An massive search of five databases involving documents in the past decade was commenced.

Findings

This review showed a significant relationship between older adults’ demographic characteristics (marital status, income, chronic disease, education level and smoking status) and health-promoting behaviors. This review showed that older adults with a high level of education, high income, chronic diseases and smoker and married older adults are associated with better health-promoting behaviors.

Originality/value

The result of the current review supports the Pender Health Promotion Model that individual personal characteristics can affect the level of engagement in health-promoting behaviors. Assessing the health-promoting behaviors of older adults can help in identifying their health needs.

Details

Working with Older People, vol. 27 no. 4
Type: Research Article
ISSN: 1366-3666

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Article
Publication date: 1 October 1995

P. Glaister

An algorithm based on flux difference splitting is presented for thesolution of two‐dimensional, steady, supercritical open channel flows. Atransformation maps a non‐rectangular…

56

Abstract

An algorithm based on flux difference splitting is presented for the solution of two‐dimensional, steady, supercritical open channel flows. A transformation maps a non‐rectangular, physical domain into a rectangular one. The governing equations are then the shallow water equations, including terms of slope and friction, in a generalised coordinate system. A regular mesh on a rectangular computational domain can then be employed. The resulting scheme has good jump capturing properties and the advantage of using boundary/body‐fitted meshes. The scheme is applied to a problem of flow in a river whose geometry induces a region of supercritical flow.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 5 no. 10
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 23 May 2022

Windinkonté Séogo

This paper assesses the effect of land ownership on household food security through its productivity enhancement effect in rural Burkina Faso.

178

Abstract

Purpose

This paper assesses the effect of land ownership on household food security through its productivity enhancement effect in rural Burkina Faso.

Design/methodology/approach

As the link between land tenure security and productivity is indirect, the study relies on a complex mixed process regression model with robustness to assess the effect of land ownership on household productivity. Then, an instrumental variable (IV) approach is followed to investigate the association between household productivity and food security. The rural development program survey data collected from 1,892 households in 2017 are used.

Findings

The complex mixed process estimation results are robust and show that land ownership has a positive effect on household productivity. From the IV results, it is found that productive households spend more on food, have a low share of expenditures on food and are less likely to experience severe food shortages, implying an improvement in their food security status. This highlights a positive association between land ownership and food security.

Originality/value

Unlike previous studies that only focused on the effect of land ownership on land-related investments and agricultural productivity, this study deepens the analysis and sheds light on how land ownership, agricultural production and food security are related. It gives empirical evidence on the importance of land policies in the struggle against food insecurity in agrarian economies.

Peer review

The peer review history for this article is available at https://publons.com/publon/10.1108/IJSE-11-2021-0658.

Details

International Journal of Social Economics, vol. 49 no. 11
Type: Research Article
ISSN: 0306-8293

Keywords

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Article
Publication date: 20 November 2007

George K. Stylios

Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…

1622

Abstract

Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 19 no. 6
Type: Research Article
ISSN: 0955-6222

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