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Article
Publication date: 3 May 2016

Amos Madhlopa

The purpose of this paper is to investigate a wall-integrated solar chimney for passive ventilation of a building cavity. Ventilation is required to improve the circulation of air…

Abstract

Purpose

The purpose of this paper is to investigate a wall-integrated solar chimney for passive ventilation of a building cavity. Ventilation is required to improve the circulation of air in the built environment. This can be achieved through natural or forced convection. Natural circulation can be driven by renewable energy, and so it promotes sustainable exploitation of energy resources. Solar energy is one of the promising renewable energy resources.

Design/methodology/approach

The chimney was designed to face the Equator on the wall of a room which required ventilation. Mean monthly daily heating and cooling loads of the room were computed with and without a solar chimney by using hourly meteorological data from nine different weather sites at low, medium and high latitudes. The chimney was implemented with and without airflow control, and simulated by using the ESP-r software.

Findings

Results show that the solar chimney with airflow control marginally reduced the heating load in the building envelope, with a similar effect being exhibited by the chimney with uncontrolled airflow. The cooling load was reduced by the controlled airflow at all the nine sites. In contrast, the uncontrolled airflow increased the cooling load at some sites. In addition, the chimney with airflow control reduced the annual total thermal load at all the sites, while the chimney with uncontrolled airflow raised the total thermal load at some locations.

Originality/value

The performance of solar chimneys designed with and without airflow control systems has been investigated under the same prevailing meteorological conditions at a given site. Findings show that controlling airflow in a solar chimney reduces the total thermal load in the built environment. This information can be applied in different parts of the world.

Details

Journal of Engineering, Design and Technology, vol. 14 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 31 December 2020

Gallus Bischof, Nikolaus Lange, Hans Juergen Rumpf and Ulrich W. Preuss

The purpose of this paper is to give an overview of the scientific evidence for reduced drinking in alcohol use disorders. While the aim of alcohol use disorders (AUD) treatment…

Abstract

Purpose

The purpose of this paper is to give an overview of the scientific evidence for reduced drinking in alcohol use disorders. While the aim of alcohol use disorders (AUD) treatment usually focuses on abstinence, only a minority of individuals with AUD enter treatment. Lack of alternative treatment goals, including reduced drinking instead of abstinence, have been identified as a potential barrier for treatment entry. Epidemiological and treatment outcome studies reveal that a large proportion of individuals with AUD are able to substantially reduce their alcohol intake for a prolonged duration of time.

Design/methodology/approach

A narrative review of the literature on prevalence rates and health effects as well as evidence-based approaches fostering reduced drinking in individuals with AUD is presented.

Findings

Reduced drinking is associated with improvements in both morbidity and mortality. Research has identified evidence-based psychosocial and pharmacological treatment approaches; however, implementation is still scarce.

Originality/value

Target groups for interventions fostering drinking reduction instead of abstinence are defined and desiderata for further research are outlined.

Details

Drugs and Alcohol Today, vol. 21 no. 1
Type: Research Article
ISSN: 1745-9265

Keywords

Article
Publication date: 26 October 2018

Tugrul Oktay, Harun Celik and Ilke Turkmen

The purpose of this paper is to examine the success of constrained control on reducing motion blur which occurs as a result of helicopter vibration.

Abstract

Purpose

The purpose of this paper is to examine the success of constrained control on reducing motion blur which occurs as a result of helicopter vibration.

Design/methodology/approach

Constrained controllers are designed to reduce the motion blur on images taken by helicopter. Helicopter vibrations under tight and soft constrained controllers are modeled and added to images to show the performance of controllers on reducing blur.

Findings

The blur caused by vibration can be reduced via constrained control of helicopter.

Research limitations/implications

The motion of camera is modeled and assumed same as the motion of helicopter. In model of exposing image, image noise is neglected, and blur is considered as the only distorting effect on image.

Practical implications

Tighter constrained controllers can be implemented to take higher quality images by helicopters.

Social implications

Recently, aerial vehicles are widely used for aerial photography. Images taken by helicopters mostly suffer from motion blur. Reducing motion blur can provide users to take higher quality images by helicopters.

Originality/value

Helicopter control is performed to reduce motion blur on image for the first time. A control-oriented and physic-based model of helicopter is benefited. Helicopter vibration which causes motion blur is modeled as blur kernel to see the effect of helicopter vibration on taken images. Tight and soft constrained controllers are designed and compared to denote their performance in reducing motion blur. It is proved that images taken by helicopter can be prevented from motion blur by controlling helicopter tightly.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 21 November 2015

Patrick J. Hurley

In this paper, I synthesize the prior psychology literature on ego depletion and apply this literature to an auditing setting. Ego depletion refers to a reduced desire or ability…

Abstract

In this paper, I synthesize the prior psychology literature on ego depletion and apply this literature to an auditing setting. Ego depletion refers to a reduced desire or ability to use self-control in task performance due to using self-control on prior tasks. I focus on the likely causes and consequences of depletion in an auditing setting, as well as means of mitigating depletion and recovering self-control resources. While ego depletion theory is prevalent in the psychology literature, little is known about whether or how ego depletion affects professionals on meaningful task performance. As a result, this synthesis is aimed at stimulating future ego depletion research in accounting, and specifically auditing, by surveying existing literature and applying this literature to an auditing setting. Further, I develop 13 questions for future research to investigate. My synthesis reveals that ego depletion likely has a pervasive effect in an auditing setting, and can hinder auditors’ judgment and decision-making (JDM) quality. Therefore, this synthesis helps to provide a greater understanding of the impact of auditing tasks on individuals, and refines both auditor JDM and ego depletion theories.

Details

Journal of Accounting Literature, vol. 35 no. 1
Type: Research Article
ISSN: 0737-4607

Keywords

Article
Publication date: 4 March 2019

Wei Huang

This paper aims to investigate the interconnections between corporate ownership, tax system and controlling shareholder tunneling through intercorporate loans in an emerging…

Abstract

Purpose

This paper aims to investigate the interconnections between corporate ownership, tax system and controlling shareholder tunneling through intercorporate loans in an emerging market setting.

Design/methodology/approach

China’s Enterprises Income Tax reform in 2008 abolished its previous multiple-tiers tax system under which foreign direct investment (FDI) firms enjoyed preferential tax rates than domestic firms by introducing a new unified-rate tax system. Using difference-in-differences tests, the author analyzes changes of controlling shareholders tunneling through intercorporate loans among Chinese listed companies around this reform.

Findings

The author documents significant reductions of intercorporate loans after the reform. More importantly, the author reveals that foreign-invested firms experienced larger reductions of intercorporate loans than domestic firms. The author also shows that state association matters for domestic firms’ response to the reform. In addition, the author documents positive stock market reaction to the tax reform announcement for firms that exhibited higher level of tunneling prior to the reform, indicating market expectation of reduced principal-principal conflict post-reform.

Research limitations/implications

The findings suggest effective corporate governance system is warranted to constrain intercorporate fund transfers in emerging markets where tax incentives are used for attracting inward foreign direct investments. Institutional reforms in emerging markets aimed at removing market frictions can alleviate the problem of controlling shareholder expropriations of minority interests or tunneling.

Originality/value

This is a pioneering study that reveals the role of tax as a public governance mechanism in weak minority investor protection environment.

Details

International Journal of Accounting & Information Management, vol. 27 no. 1
Type: Research Article
ISSN: 1834-7649

Keywords

Article
Publication date: 8 March 2010

David A. Sanders, Martin Langner and Giles E. Tewkesbury

The purpose of this paper is to present powered‐wheelchair transducers and systems that provide more control, reduced veer on slopes, and improved energy conservation, while…

Abstract

Purpose

The purpose of this paper is to present powered‐wheelchair transducers and systems that provide more control, reduced veer on slopes, and improved energy conservation, while reducing effort. They are especially significant for people with movement disorders who lack sufficient hand‐grasp and release ability or sufficient targeting skill to use joysticks.

Design/methodology/approach

Laboratory test rigs are created to test proportional switches and teach potential users. Then, trials are conducted with a rolling road and in real situations. Caster angle‐measurement is selected to provide feedback to minimize drift away from a chosen course and an electronic solution was created to match driver control to caster‐steering‐position. A case study is described as an example.

Findings

Results and advantages are presented from changing from using a set of digital‐switches to a set of new variable‐switches and then adding a sensor system to prevent veer on slopes. Systems have been tested for nearly two years and shown to assist powered‐wheelchair‐users with poor targeting skills.

Research limitations/implications

The research used wheelchairs with caster‐wheels but the systems could easily be used on other wheelchairs.

Practical implications

Simple input‐devices are presented that isolate gross motor function and are tolerant to involuntary movements (proportional‐switches). A sensor system is presented that assists users in steering across sloping or uneven ground.

Originality/value

Proportional‐switches and sensors are shown to reduce veer and provide more control over turn and forward speed and turn radius while reducing frustration and improving energy conservation. The simple and affordable systems could be created and attached to many standard powered‐wheelchairs in many organisations.

Details

Industrial Robot: An International Journal, vol. 37 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Abstract

Details

Modelling the Riskiness in Country Risk Ratings
Type: Book
ISBN: 978-0-44451-837-8

Article
Publication date: 10 July 2007

Ranjan Ganguli, Beatrix Jehnert, Jens Wolfram and Peter Voersmann

To investigate the use of centre of gravity location on reducing cyclic pitch control for helicopter UAV's (unmanned air vehicles) and MAV's (micro air vehicles). Low cyclic pitch…

1084

Abstract

Purpose

To investigate the use of centre of gravity location on reducing cyclic pitch control for helicopter UAV's (unmanned air vehicles) and MAV's (micro air vehicles). Low cyclic pitch is a necessity to implement the swashplateless rotor concept using trailing edge flaps or active twist using current generation low authority piezoceramic actuators.

Design/methodology/approach

An aeroelastic analysis of the helicopter rotor with elastic blades is used to perform parametric and sensitivity studies of the effects of longitudinal and lateral center of gravity (cg) movements on the main rotor cyclic pitch. An optimization approach is then used to find cg locations which reduce the cyclic pitch at a given forward speed.

Findings

It is found that the longitudinal cyclic pitch and lateral cyclic pitch can be driven to zero at a given forward speed by shifting the cg forward and to the port side, respectively. There also exist pairs of numbers for the longitudinal and lateral cg locations which drive both the cyclic pitch components to zero at a given forward speed. Based on these results, a compromise optimal cg location is obtained such that the cyclic pitch is bounded within ±5° for a BO105 helicopter rotor.

Originality/value

The reduction in the cyclic pitch due to helicopter cg location is found to significantly reduce the maximum magnitudes of the control angles in flight, facilitating the swashplateless rotor concept. In addition, the existence of cg locations which drive the cyclic pitches to zero allows for the use of active cg movement as a way to replace the cyclic pitch control for helicopter MAV's.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 13 March 2020

Biplab Kumar Guru and Inder Sekhar Yadav

This study empirically examines the effect of capital controls on the volume and composition of capital flows at aggregated as well as at disaggregated level by different asset…

Abstract

Purpose

This study empirically examines the effect of capital controls on the volume and composition of capital flows at aggregated as well as at disaggregated level by different asset classes such as debt, FDI, equity, and derivatives.

Design/methodology/approach

Several dynamic panel SYS-GMM models are employed on two sets of unique data on cross-border capital flows and capital control index along with control variables at aggregated and disaggregated level by different asset classes during 1995–2015 for a sample of 31 Asian economies.

Findings

Econometric findings suggest that higher capital controls effectively reduce gross capital flows. The reduction in gross capital flows is largely found to be on account of effectiveness of controls on equity flows. However, the impact of controls on overall debt and derivative flows is found to be insignificant. Further, it was found that an increase in direct capital controls disaggregated by inflow and outflow categories significantly reduced the inflow of debt and equity + FDI flows and outflow of equity + FDI and derivative flows. Finally, the study did not find any substitution effect (due to indirect controls) and net effect on capital flows.

Practical implications

Results of such empirical examination may enable governments in respective countries to pursue prudent and rational capital controls as a shield against capital flight and shock transmission.

Social implications

Preventing capital flight through effective controls has macroeconomic benefits such as maintaining stability in income, growth, interest rate, exchange rate, and employment levels for the society.

Originality/value

The primary contribution of the study is the analysis of effectiveness of capital controls disaggregated by different asset categories such as debt, equity, FDI, and derivatives using two unique recent data sets for a large sample of Asian economies.

Details

Journal of Economic Studies, vol. 47 no. 2
Type: Research Article
ISSN: 0144-3585

Keywords

Article
Publication date: 25 September 2009

Karine Gerard, Jean‐Pierre Grandhaye, Vincent Marchesi, Pierre Aletti, François Husson, Alain Noel and Hanna Kafrouni

The purpose of this paper is to evaluate and improve the quality and the reliability of pre‐treatment quality controls of an efficient technique of radiotherapy called IMRT…

1225

Abstract

Purpose

The purpose of this paper is to evaluate and improve the quality and the reliability of pre‐treatment quality controls of an efficient technique of radiotherapy called IMRT (intensity‐modulated radiation therapy). The aim is then to determine if the controls can be safely reduced while keeping an optimal level of quality.

Design/methodology/approach

The statistical process control method (SPC) was applied to quality assurance in IMRT. In order to characterize prostate and head‐and‐neck treatment process variability, individual value control charts and moving‐range control charts were established.

Findings

Control charts showed that prostate and head‐and‐neck treatment processes are only subject to random causes of variability, which means they are statistically controlled. It was proved that both processes are statistically stable and capable.

Originality/value

The paper shows that SPC is an efficient method to objectively determine if quality controls can be reduced.

Details

Journal of Quality in Maintenance Engineering, vol. 15 no. 4
Type: Research Article
ISSN: 1355-2511

Keywords

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