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Article
Publication date: 5 August 2019

Amer Al-Omari, Amjad Al-Nasser and Enrico Ciavolino

Lifetime data are used in many different applied sciences, like biomedicine, engineering, insurance and finance and others. The purpose of this paper is to develop a new…

Abstract

Purpose

Lifetime data are used in many different applied sciences, like biomedicine, engineering, insurance and finance and others. The purpose of this paper is to develop a new acceptance sampling plans for Rama distribution when the mean lifetime test is truncated at a pre-determined time. The minimum sample sizes required to assert the specified life mean is obtained for a given customer’s risk. The operating characteristic function values of the sampling plans and producer’s risk are calculated.

Design/methodology/approach

The results are illustrated using numerical examples and a real data set is considered to illustrate the performance of the suggested acceptance sampling plans and how it can be used for the industry applications.

Findings

This paper shows a new acceptance sampling plans based on Rama distribution in the particular case when the mean life time test is truncated.

Originality/value

The results calculated in this paper demonstrate the differences between OC values for different distributions taken into account. In particular, OC values of Rama distribution are found to be less than the proposed distribution counterparts.

Details

International Journal of Quality & Reliability Management, vol. 36 no. 7
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 3 August 2020

Jimut Bahan Chakrabarty, Shovan Chowdhury and Soumya Roy

The purpose of this paper is to design an optimal reliability acceptance sampling plan (RASP) using the Type-I generalized hybrid censoring scheme (GHCS) for…

Abstract

Purpose

The purpose of this paper is to design an optimal reliability acceptance sampling plan (RASP) using the Type-I generalized hybrid censoring scheme (GHCS) for non-repairable products sold under the general rebate warranty. A cost function approach is proposed for products having Weibull distributed lifetimes incorporating relevant costs.

Design/methodology/approach

For Weibull distributed product lifetimes, acceptance criterion introduced by Lieberman and Resnikoff (1955) is derived for Type-I GHCS. A cost function is formulated using expected warranty cost and other relevant cost components incorporating the acceptance criterion. The cost function is optimized following a constrained optimization approach to arrive at the optimum RASP. The constraint ensures that the producer's and the consumer's risks are maintained at agreed-upon levels.

Findings

Optimal solution using the above approach is obtained for Type-I GHCS. As a special case of Type-I GHCS, the proposed approach is also used to arrive at the optimal design for Type-I hybrid censoring scheme as shown in Chakrabarty et al. (2019). Observations regarding the change in optimal design and computational times between the two censoring schemes are noted. An extensive simulation study is performed to validate the model for finite sample sizes and the results obtained are found to be in strong agreement. In order to analyze the sensitivity of the optimal solution due to misspecification of parameter values and cost components, a well-designed sensitivity analysis is carried out using a real-life failure data set from Lawless (2003). Interesting observations are made regarding the change in optimal cost due to change in parameter values, the impact of warranty cost in optimal design and change in optimal design due to change in lot sizes.

Originality/value

The research presents an approach for designing optimal RASPs using Type-I generalized hybrid censoring. The study formulates optimum life test sampling plans by minimizing the average aggregate costs involved, which makes it valuable in dealing with real-life problems pertaining to product quality management.

Details

International Journal of Quality & Reliability Management, vol. 38 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 30 September 2021

Damla Yüksel, Yigit Kazancoglu and P.R.S Sarma

This paper aims to create a new decision-making procedure that uses “Lot-by-Lot Acceptance Sampling Plan by Attributes” methodology in the production processes when any…

Abstract

Purpose

This paper aims to create a new decision-making procedure that uses “Lot-by-Lot Acceptance Sampling Plan by Attributes” methodology in the production processes when any production interruption is observed in tobacco industry, which is a significant example of batch production.

Design/methodology/approach

Based on the fish bone diagram, the reasons of the production interruptions are categorized, then Lot-by-Lot Acceptance Sampling Plan by Attributes is studied to overcome the reasons of the production interruptions. Furthermore, managerial aspects of decision making are not ignored and hence, acceptance sampling models are determined by an Analytical Hierarchy Process (AHP) among the alternative acceptance sampling models.

Findings

A three-phased acceptance sampling model is generated for determination of the reasons of production interruptions. Hence, the necessary actions are provided according to the results of the proposed acceptance sampling model. Initially, 729 alternative acceptance sampling models are found and 38 of them are chosen by relaxation. Then, five acceptance sampling models are determined by AHP.

Practical implications

The current experience dependent decision mechanism is suggested to be replaced by the proposed acceptance sampling model which is based on both statistical and managerial decision-making procedure.

Originality/value

Acceptance sampling plans are considered as a decision-making procedure for various cases in production processes. However, to the best of our knowledge Lot-by-Lot Acceptance Sampling Plan by Attributes has not been considered as a decision-making procedure for batch production when any production interruption is investigated.

Details

International Journal of Quality & Reliability Management, vol. 39 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 15 February 2021

Nirmalendu Biswas, Nirmal K. Manna, Dipak Kumar Mandal and Rama Subba Reddy Gorla

The purpose of this study is to address magnetohydrodynamic (MHD) bioconvection caused by the swimming of oxytactic microorganisms in a linearly heated square cavity…

Abstract

Purpose

The purpose of this study is to address magnetohydrodynamic (MHD) bioconvection caused by the swimming of oxytactic microorganisms in a linearly heated square cavity filled with porous media and Cu–water nanofluid. The effects of different multiphysical aspects are demonstrated using local distributions as well as global quantities for fluid flow, temperature, oxygen concentration and microorganisms population.

Design/methodology/approach

The coupled transport equations are converted into the nondimensional partial differential equations, which are solved numerically using a finite volume-based computing code. The flow of Cu–water nanofluid through the pores of porous media is formulated following the Brinkman–Forchheimer–Darcy model. The swimming of oxytactic microorganisms is handled following a continuum model.

Findings

The analysis of transport phenomena of bioconvection is performed in a linearly heated porous enclosure containing Cu–water nanofluid and oxytactic microorganisms under the influence of magnetic fields. The application of such a system could have potential impacts in diverse fields of engineering and science. The results show that the flow and temperature distribution along with the isoconcentrations of oxygen and microorganisms is markedly affected by the involved governing parameters.

Research limitations/implications

Similar study of bioconvection could be extended further considering thermal radiation, chemical attraction, gravity and light.

Practical implications

The outcomes of this investigation could be used in diverse fields of multiphysical applications, such as in food industries, chemical processing equipment, fuel cell technology and enhanced oil recovery.

Originality/value

The insight of the linear heating profile reveals a special attribute of simultaneous heating and cooling zones along the heated side. With such an interesting feature, the MHD bioconvection of oxytactic microorganisms in nanofluid-filled porous substance is not reported so far.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 11
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 23 November 2020

Nirmalendu Biswas, Aparesh Datta, Nirmal K. Manna, Dipak Kumar Mandal and Rama Subba Reddy Gorla

This study aims to explore magnetohydrodynamic (MHD) thermo-bioconvection of oxytactic microorganisms in multi-physical directions addressing thermal gradient, lid motion…

Abstract

Purpose

This study aims to explore magnetohydrodynamic (MHD) thermo-bioconvection of oxytactic microorganisms in multi-physical directions addressing thermal gradient, lid motion, porous substance and magnetic field collectively using a typical differentially heated two-sided lid-driven cavity. The consequences of a range of pertinent parameters on the flow structure, temperature, oxygen isoconcentration and microorganisms’ isoconcentration are examined and explained in great detail.

Design/methodology/approach

Two-dimensional governing equations in a two-sided lid-driven porous cavity heated differentially and packed with oxytactic microorganisms under the influence of the magnetic field are solved numerically using the finite volume method-based computational fluid dynamics code. The evolved flow physics is analyzed assuming a steady laminar incompressible Newtonian flow within the validity of the Boussinesq approximation. The transport of oxytactic microorganisms is formulated by augmenting the continuum model.

Findings

The mechanisms involved with MHD-mixed thermo-bioconvection could have potential benefits for industrial exploitation. The distributions of fluid flow, temperature, oxygen and motile microorganisms are markedly modified with the change of convection regime. Both speed and direction of the translating walls significantly influence the concentration of the motile microorganisms. The concentration of oxygen and motile microorganisms is found to be higher at the upper portion of the cavity. The overall patterns of the fluid flow, temperature and the oxygen and microorganism distributions are markedly affected by the increase of magnetic field strength.

Research limitations/implications

The concept of the present study could be extended to other areas of bioconvection in the presence of gravity, light or chemical attraction.

Practical implications

The findings of the present study could be used to multi-physical applications like biomicrosystems, pollutant dispersion in aquifers, chemical catalytic converters, geothermal energy usage, petroleum oil reservoirs, enhanced oil recovery, fuel cells, thermal energy storage and others.

Originality/value

The MHD-mixed thermo-bioconvection of oxytactic microorganisms is investigated under different parametric conditions. The effect of pertinent parameters on the heat and mass transfers are examined using the Nusselt number and Sherwood number.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 31 July 2007

Philip Constable and Nooch Kuasirikun

The purpose of this paper is to examine the relationship between accounting and the early roots of the nation‐state in mid nineteenth‐century Siam/Thailand.

1853

Abstract

Purpose

The purpose of this paper is to examine the relationship between accounting and the early roots of the nation‐state in mid nineteenth‐century Siam/Thailand.

Design/methodology/approach

First, the paper examines the theoretical inter‐relationship between accounting and nationalism. Second, it relates this theoretical understanding to a study of the changing concepts, methods and structures of indigenous Siamese accounting at a time of transition when foreign mercantile influence was beginning to have an impact on the mid nineteenthcentury Siamese economy. Third, the paper analyses how these accounting structures and practices came to constitute a socio‐political instrument, which contributed to the administrative development of a Siamese dynastic state by the mid nineteenth‐century. Finally, the paper studies the ways in which this dynastic state began to promote national characteristics through the use of its accounts to create a sense of Siamese cultural identity.

Findings

The findings emphasise the important role of accounting in the construction of political and national identity.

Originality/value

This inter‐disciplinary paper highlights a general neglect in the accounting literature of the instrumental role of accounting in nation‐state formation as well as offering a re‐interpretation of Thai historiography from an accounting viewpoint. Moreover as an example of alternative accounting practice, this paper provides an analysis of indigenous accounting methods and structures in mid nineteenth‐century Siam/Thailand at the point when they were becoming increasingly influenced by foreign mercantilism.

Details

Accounting, Auditing & Accountability Journal, vol. 20 no. 4
Type: Research Article
ISSN: 0951-3574

Keywords

Book part
Publication date: 27 August 2016

Carl Lin and Myeong-Su Yun

The minimum wage has been regarded as an important element of public policy for reducing poverty and inequality. Increasing the minimum wage is supposed to raise earnings…

Abstract

The minimum wage has been regarded as an important element of public policy for reducing poverty and inequality. Increasing the minimum wage is supposed to raise earnings for millions of low-wage workers and therefore lower earnings inequality. However, there is no consensus in the existing literature from industrialized countries regarding whether increasing the minimum wage has helped lower earnings inequality. China has recently exhibited rapid economic growth and widening earnings inequality. Since China promulgated new minimum wage regulations in 2004, the magnitude and frequency of changes in the minimum wage have been substantial, both over time and across jurisdictions. The growing importance of research on the relationship between the minimum wage and earnings inequality and its controversial nature have sparked heated debate in China, highlighting the importance of rigorous research to inform evidence-based policy making. We investigate the contribution of the minimum wage to the well-documented rise in earnings inequality in China from 2004 to 2009 by using city-level minimum wage panel data and a representative Chinese household survey, and we find that increasing the minimum wage reduces inequality – by decreasing the earnings gap between the median and the bottom decile – over the analysis period.

Details

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

Keywords

Book part
Publication date: 3 May 2011

Niron Hashai, Tamar Almor, Marina Papanastassiou, Fragkiskos Filippaios and Ruth Rama

This chapter examines the interrelationships between internationalization and product diversification among the world's l35 largest food and beverage enterprises. Based on…

Abstract

This chapter examines the interrelationships between internationalization and product diversification among the world's l35 largest food and beverage enterprises. Based on the argument that food and beverage enterprises enjoy economies of scope when moderately diversifying into new countries and product areas, but encounter resource constraints when extremely diversified and internationalized, we expect to find an inverted U-shaped relationship between the two strategies. Nevertheless, we find that the relationships between the two strategies show both an inverted U-shaped (when geographic diversification is the dependent variable and product diversification the independent one) and a U-shaped pattern (when product diversification is the dependent variable and geographic diversification the independent one). These results imply that the relationships between internationalization and product diversification among food and beverage enterprises are more complex than currently conceived.

Details

The Future of Foreign Direct Investment and the Multinational Enterprise
Type: Book
ISBN: 978-0-85724-555-7

Keywords

Article
Publication date: 5 February 2018

Mohamed Ghazi Al-Fandi, Nid’a Hamdan Alshraiedeh, Rami Joseph Oweis, Rawan Hassan Hayajneh, Iman Riyad Alhamdan, Rama Adel Alabed and Omar Farhan Al-Rawi

This paper aims to report a prototype of a reliable method for rapid, sensitive bacterial detection by using a low-cost zinc oxide nanorods (ZnONRs)-based electrochemical sensor.

Abstract

Purpose

This paper aims to report a prototype of a reliable method for rapid, sensitive bacterial detection by using a low-cost zinc oxide nanorods (ZnONRs)-based electrochemical sensor.

Design/methodology/approach

The ZnONRs have been grown on the surface of a disposable, miniaturized working electrode (WE) using the low-temperature hydrothermal technique. Scanning electron microscopy and energy dispersion spectroscopy have been performed to characterize the distribution as well as the chemical composition of the ZnONRs on the surface, respectively. Moreover, the cyclic voltammetry test has been implemented to assess the effect of the ZnONRs on the signal conductivity between −1 V and 1 V with a scan rate of 0.01 V/s. Likewise, the effect of using different bacterial concentrations in phosphate-buffered saline has been investigated.

Findings

The morphological characterization has shown a highly distributed ZnONR on the WE with uneven alignment. Also, the achieved response time was about 12 minutes and the lower limit of detection was approximately 103 CFU abbreviation for Colony Forming Unit/mL.

Originality/value

This paper illustrates an outcome of an experimental work on a ZnONRs-based electrochemical biosensor for direct detection of bacteria.

Details

Sensor Review, vol. 38 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Book part
Publication date: 15 September 2014

Stephanie D. Grimm and Sheneeta W. White

Section 404 of the Sarbanes–Oxley Act (SOX) altered the relationship between auditors and their clients by requiring an external audit of companies’ internal controls…

Abstract

Section 404 of the Sarbanes–Oxley Act (SOX) altered the relationship between auditors and their clients by requiring an external audit of companies’ internal controls. Regulatory guidance is interpreted and applied by external auditors to comply with SOX. The purpose of this paper is to apply service operations management theories and techniques to the internal control audit process to better understand the role regulatory guidance plays in audit services. We discuss service operations management theories that apply to the production of audit services and employ the operations management technique of simulation to examine the effects of a historical relationship between the client and the auditor, information sharing between the client and the auditor, and the auditor’s perceived risk of the client on the internal control audit process. The application of service operations management theories and the simulation results illustrate that risk and information sharing are key factors for the audit process. The results suggest the updated Public Company Accounting Oversight Board guidance from Auditing Standard 2 to Auditing Standard 5 appropriately increased audit effectiveness by encouraging risk-based judgments and information sharing. This paper merges accounting and service operations management research to examine the effects of regulatory guidance on the internal control audit process. The paper uses simulation to illustrate the importance of interpreting regulatory guidance and the specific effects of risk and information sharing on the internal control audit process.

Details

Research on Professional Responsibility and Ethics in Accounting
Type: Book
ISBN: 978-1-78441-163-3

Keywords

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