Search results

1 – 10 of over 53000
To view the access options for this content please click here
Article
Publication date: 14 October 2021

Hui Yu, Wei Yang, Na Xu and Yang Du

After receiving advertising messages, most consumers rarely purchase the advertised products at once, which results in a delay between advertising exposure and its effect…

Abstract

Purpose

After receiving advertising messages, most consumers rarely purchase the advertised products at once, which results in a delay between advertising exposure and its effect. This paper is devoted to exploring the advertising decision and coordination issues for a supply chain system subject to advertising immediate and delayed effects.

Design/methodology/approach

By applying the game theory, the differential game models with delay are constructed for the supply chain to examine the equilibrium advertising efforts, brand goodwill and the optimal profits under the different cooperation situations. A class of transfer payment contracts is designed to achieve the best outcome of the supply chain. Illustrative examples are given to demonstrate the effectiveness of addressed results and provide some managerial perspectives.

Findings

It can be found that the complete cooperation situation can stimulate the advertising investment, drive the product demand and improve the economic profit. Also, a class of transfer payment contracts is designed in this paper, such that the supply chain can perfectly realize the profit maximization, and each member can achieve the Pareto improvement.

Research limitations/implications

This work does not address the random market environment, which can be filled in the future. Furthermore, this paper has been done in a single supply chain structure. It is an interesting future line of research when taking competitive behavior (e.g. competition among manufacturers, retailers or supply chains) into account.

Practical implications

This study will help managers make advertising strategies, advise an optimal cooperation way and design the coordination contracts to ensure the economic development of the supply chain. These obtained conclusions may provide a valuable decision-support for marketing management.

Originality/value

For a supply chain, the most previous literature about dynamic advertising models focused on a single advertising effect-immediate effect. This work explores advertising strategy with double advertising effects and investigates the coordinating power of new transfer payment contracts.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

To view the access options for this content please click here
Article
Publication date: 1 March 1998

TOUFIC M. MEZHER and WISSAM TAWIL

The present paper presents the major causes of delays in the construction industry in Lebanon and the relative importance of these postponements. A survey of a randomly…

Downloads
1664

Abstract

The present paper presents the major causes of delays in the construction industry in Lebanon and the relative importance of these postponements. A survey of a randomly selected sample of 11 owners, 15 contractors and 10 architectural/engineering (A/E) firms from Lebanon was undertaken. The survey included 64 causes of delay, grouped into 10 major groups, in which the participants were asked to indicate their level of importance of each delay. The level of importance of the causes and the groups were measured and ranked by the importance index for owners, contractors and A/E firms. It was found that all three parties generally agreed on the ranking of the major categories of delay factors. Owners had more concerns with regard to financial issues, while contractors ranked contractual relationships highest, and finally, A/E firms ranked project management highest.

Details

Engineering, Construction and Architectural Management, vol. 5 no. 3
Type: Research Article
ISSN: 0969-9988

Keywords

To view the access options for this content please click here
Article
Publication date: 13 June 2016

Ping He and Tao Fan

– The purpose of this paper is with delay-independent stabilization of nonlinear systems with multiple time-delays and its application in chaos synchronization of Rössler system.

Abstract

Purpose

The purpose of this paper is with delay-independent stabilization of nonlinear systems with multiple time-delays and its application in chaos synchronization of Rössler system.

Design/methodology/approach

Based on linear matrix inequality and algebra Riccati matrix equation, the stabilization result is derived to guarantee asymptotically stable and applicated in chaos synchronization of Rössler chaotic system with multiple time-delays.

Findings

A controller is designed and added to the nonlinear system with multiple time-delays. The stability of the nonlinear system at its zero equilibrium point is guaranteed by applying the appropriate controller signal based on linear matrix inequality and algebra Riccati matrix equation scheme. Another effective controller is also designed for the global asymptotic synchronization on the Rössler system based on the structure of delay-independent stabilization of nonlinear systems with multiple time-delays. Numerical simulations are demonstrated to verify the effectiveness of the proposed controller scheme.

Originality/value

The introduced approach is interesting for delay-independent stabilization of nonlinear systems with multiple time-delays and its application in chaos synchronization of Rössler system.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 9 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

Content available
Article
Publication date: 17 December 2019

Yotsanon Sikkhajan and Wandee Sirichokchatchawan

The purpose of this paper is to determine the factors associated with patient delay among tuberculosis patients in border hospitals, Chiang Rai province, Thailand.

Abstract

Purpose

The purpose of this paper is to determine the factors associated with patient delay among tuberculosis patients in border hospitals, Chiang Rai province, Thailand.

Design/methodology/approach

A cross-sectional study was conducted in the four biggest border hospitals in Chiang Rai province, Thailand during May to July 2018 among 103 identified TB cases. Data were collected by a face-to-face interview with structured questionnaire on patients’ general characteristics, HIV status and patient delay status. Descriptive statistics were used to analyze the patients’ general characteristics, HIV and patient delay status. The association among variables and patient delay was analyzed by χ2-test. The variables with p-value<0.20 obtained in bivariate analysis were further analyzed by binary logistic regression and considered significant with p-value<0.05.

Findings

All patients enrolled, most were reported with patient delay (65.0 percent). Bivariate analysis demonstrated that level of education, nationality and HIV status were associated factors for patient delay. Among these factors, binary logistic regression revealed that HIV negative TB patients were increased 6.806-fold odds of being patient delay (OR = 6.806; 95% CI: 1.174–39.462), while non-Thai TB patients were also increased 2.824-fold odds of being patient delay (OR = 2.824; 95% CI: 1.041–7.660).

Originality/value

Patient delay among TB patients in Chiang Rai province was high. This study further supports the requirement on promoting of TB knowledge and awareness emphasized on non-Thai population and general public along the border areas of Chiang Rai province.

Details

Journal of Health Research, vol. 34 no. 3
Type: Research Article
ISSN: 2586-940X

Keywords

To view the access options for this content please click here
Article
Publication date: 19 October 2010

Stephen Thomas Ward, Sean Strong, Rachael Louise Goodchild and Ahsan Zafar Zaidi

Patients undergoing emergency appendicectomy incur various delays from the time of symptom onset to the time of discharge from hospital. The centralisation of hospital…

Abstract

Purpose

Patients undergoing emergency appendicectomy incur various delays from the time of symptom onset to the time of discharge from hospital. The centralisation of hospital services over recent years has resulted in some patients who attend hospital as an emergency requiring transfer to a different site. An additional delay by way of transfer is thus incurred. The aim of this study was to test for association between various characterised delays with disease and patient outcomes.

Design/methodology/approach

Hospital Episode Statistics (HES) data were used to identify all patients admitted over a one‐year period undergoing appendicectomy. Demographic and time data were extracted from hospital databases and case notes.

Findings

A total of 247 patients were identified from HES data; 25 per cent of patients presented to hospital E necessitating transfer to hospital H. There was no evidence of an association between patient delays, surgeon delays or theatre delays with advanced pathology and complicated appendicitis was not associated with a longer post‐operative hospital stay. The delay to be seen by the surgeons was significantly longer if transferred from one hospital to another, but this did not contribute to a significant difference between the overall delay from admission to operation, overall length of stay or advanced pathology.

Originality/value

The individual delays along the clinical pathway in a patient presenting to hospital with acute appendicitis have been characterised. Patients with acute appendicitis can be safely assessed at one hospital‐site and transferred to another with emergency surgery provision without affecting the delay to operation.

Details

Clinical Governance: An International Journal, vol. 15 no. 4
Type: Research Article
ISSN: 1477-7274

Keywords

To view the access options for this content please click here
Article
Publication date: 1 May 2001

R.A. HARRIS and S. SCOTT

The paper describes four methods of dealing with delay claims that effectively sum up the main approaches to this problem that have been offered in the literature. This is…

Abstract

The paper describes four methods of dealing with delay claims that effectively sum up the main approaches to this problem that have been offered in the literature. This is then followed by a description and discussion of results from a new survey aimed at finding out exactly how professionals in the UK construction industry approach these difficult issues. It appears that those who deal with delay claims in the UK are likely to use a critical path method network to do this and generally approve of a methodology that attempts to understand how well the contractor would have fared ‘but for’ the existence of employer‐responsible delays. There is less agreement about who should be said to own the float, but as is explained in the paper, it is possible for this matter to be dealt with by the insertion of a clause in the contract documents.

Details

Engineering, Construction and Architectural Management, vol. 8 no. 5/6
Type: Research Article
ISSN: 0969-9988

Keywords

To view the access options for this content please click here
Article
Publication date: 9 July 2018

Changjin Xu and Peiluan Li

The purpose of this paper is to investigate the existence and global exponential stability of periodic solution of memristor-based recurrent neural networks with…

Abstract

Purpose

The purpose of this paper is to investigate the existence and global exponential stability of periodic solution of memristor-based recurrent neural networks with time-varying delays and leakage delays.

Design/methodology/approach

The differential inequality theory and some novel mathematical analysis techniques are applied.

Findings

A set of sufficient conditions which guarantee the existence and global exponential stability of periodic solution of involved model is derived.

Practical implications

It plays an important role in designing the neural networks.

Originality/value

The obtained results of this paper are new and complement some previous studies. The innovation of this paper concludes two aspects: the analysis on the existence and global exponential stability of periodic solution of memristor-based recurrent neural networks with time-varying delays and leakage delays is first proposed; and it is first time to establish the sufficient criterion which ensures the existence and global exponential stability of periodic solution of memristor-based recurrent neural networks with time-varying delays and leakage delays.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 11 no. 3
Type: Research Article
ISSN: 1756-378X

Keywords

To view the access options for this content please click here
Article
Publication date: 25 January 2008

Elbrous M. Jafarov

This paper aims to use a new design approach based on a Lagrange mean value theorem for the stabilization of multivariable input‐delayed system by linear controller.

Abstract

Purpose

This paper aims to use a new design approach based on a Lagrange mean value theorem for the stabilization of multivariable input‐delayed system by linear controller.

Design/methodology/approach

The delay‐dependent asymptotical stability conditions are derived by using augmented Lyapunov‐Krasovskii functionals and formulated in terms of conventional Lyapunov matrix equations and some simple matrix inequalities. Proposed design approach is extended to robust stabilization of multi‐variable input‐delayed systems with unmatched parameter uncertainties. The maximum upper bound of delay size is computed by using a simple optimization algorithm.

Findings

A liquid monopropellant rocket motor with a pressure feeding system is considered as a numerical design example. Design example shows the effectiveness of the proposed design approach.

Research limitations/implications

The proposed approach can be used in the analysis and design of the uncertain multivariable time‐delay systems.

Originality/value

The paper has a great potential in the stability analysis of time‐delay systems and design of time‐delay controllers and may openup a new direction in this area.

Details

Aircraft Engineering and Aerospace Technology, vol. 80 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

To view the access options for this content please click here
Article
Publication date: 3 July 2009

Wang Xinlong and Li Yafeng

The purpose of this paper is to discuss the applicability of Global Positioning System (GPS) ionospheric delay correction models. Ionospheric delay is the most influential…

Abstract

Purpose

The purpose of this paper is to discuss the applicability of Global Positioning System (GPS) ionospheric delay correction models. Ionospheric delay is the most influential error source in GPS positioning, and ionospheric refraction is difficult to be corrected by dual frequency measurement for the common single frequency GPS receivers. Generally, ionospheric models are employed to correct errors. In order to analyze the ionospheric influence to GPS signals and the accuracy and adaptability of GPS ionospheric error correction models a quantificational analysis for ionospheric error correction models is absolutely necessary.

Design/methodology/approach

On the base of the mechanism of ionospheric error, the Klobuchar model that is widely used and actual measured correction model (including local and global ionospheric error correction models) are analyzed in detail. With the data about ionosphere obtained from GPS authority Crustal Dynamics Data Information System, the precision and adaptability of two kinds of ionospheric error correction model are validated, and a predigested method of investigating precision of local ionospheric error correction model is presented.

Findings

Klobuchar model has higher precision in middle or low latitude than in high latitude, and ionospheric delay fluctuates acutely in a day with a day‐cycle. Ionospheric delay varies as the latitude changes: ionospheric delay is largest around equator and smallest in the areas of two poles, which shows symmetry. The relationship between ionospheric delay and longitude is similar to the relationship between ionospheric delay and latitude. The fitting model has better effect than Klobuchar model.

Originality/value

This paper thoroughly researches GPS ionospheric error correction models. The conclusions are presented for the selection of GPS correction models, that it is useful for practical engineering application and will be the theoretic foundation for the improvement of the GPS accurate positioning.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

To view the access options for this content please click here
Article
Publication date: 7 September 2021

Christian Nnaemeka Egwim, Hafiz Alaka, Luqman Olalekan Toriola-Coker, Habeeb Balogun, Saheed Ajayi and Raphael Oseghale

This paper aims to establish the most underlying factors causing construction projects delay from the most applicable.

Abstract

Purpose

This paper aims to establish the most underlying factors causing construction projects delay from the most applicable.

Design/methodology/approach

The paper conducted survey of experts using systematic review of vast body of literature which revealed 23 common factors affecting construction delay. Consequently, this study carried out reliability analysis, ranking using the significance index measurement of delay parameters (SIDP), correlation analysis and factor analysis. From the result of factor analysis, this study grouped a specific underlying factor into three of the six applicable factors that correlated strongly with construction project delay.

Findings

The paper finds all factors from the reliability test to be consistent. It suggests project quality control, project schedule/program of work, contractors’ financial difficulties, political influence, site conditions and price fluctuation to be the six most applicable factors for construction project delay, which are in the top 25% according to the SIDP score and at the same time are strongly associated with construction project delay.

Research limitations/implications

This paper is recommending that prospective research should use a qualitative and inductive approach to investigate whether any new, not previously identified, underlying factors that impact construction projects delay can be discovered as it followed an inductive research approach.

Practical implications

The paper includes implications for the policymakers in the construction industry in Nigeria to focus on measuring the key suppliers’ delivery performance as late delivery of materials by supplier can result in rescheduling of work activities and extra time or waiting time for construction workers as well as for the management team at site. Also, construction stakeholders in Nigeria are encouraged to leverage the amount of data produced from backlog of project schedules, as-built drawings and models, computer-aided designs (CAD), costs, invoices and employee details, among many others through the aid of state-of-the-art data driven technologies such as artificial intelligence or machine learning to make key business decisions that will help drive further profitability. Furthermore, this study suggests that these stakeholders use climatological data that can be obtained from weather observations to minimize impact of bad weather during construction.

Originality/value

This paper establishes the three underlying factors (late delivery of materials by supplier, poor decision-making and Inclement or bad weather) causing construction projects delay from the most applicable.

Details

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

Keywords

1 – 10 of over 53000