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This article presents a new chain sampling plan for three atttibute classes where items are classified into three categories namely good, marginal and bad. Various performance characteristics of interest to quality control engineers and plan designers are derived through GERT approach. In order to facilitate the operation and construction of the plan, Poisson unity values have been tabulated for a useful subset of the proposed plan.

Introduces a conditional repetitive group sampling plan. The OC and ASN functions are derived by GERT approach. The present development would be a valuable addition to the literature and a useful device to quality control practitioners and also to quality control engineers and plan designers in the development of further new plans.

The purpose of this paper is to propose a new mixed repetitive group sampling (RGS) plan based on the process capability index, C_pk, where the quality characteristics of interest follow the normal distribution with unknown mean and unknown variance. Tables are constructed to determine the optimal parameters for practical applications for both symmetric and asymmetric fraction non-conforming cases. The advantages of this proposed mixed sampling plan are also discussed. The proposed sampling plan is also compared with other existing sampling plans.

In order to determine the optimal parameters of the proposed mixed RGS plan based on C_pk, the authors constructed tables for various combinations of acceptable and limiting quality levels (LQLs). For constructing tables, the authors followed the approach of two points on the operating characteristic (OC) curve. The optimal problem is formulated as a non-linear programming where the objective function to be minimized is the average sample number (ASN) and the constraints are related to lot acceptance probabilities at acceptable quality level and LQL under the OC curve.

The proposed mixed RGS plan will be a new addition to the literature of acceptance sampling. It is shown that the proposed mixed plan involves minimum ASN with desired protection to both producers and consumers compared to other existing sampling plans. The practical application of the proposed mixed sampling plan is also explained with an illustrative real-time example.

In this paper, the authors propose a new mixed RGS plan based on the process capability index C_pk, where the quality characteristic of interest follows the normal distribution with unknown mean and unknown variance. Tables are constructed to determine the optimal parameters for practical applications. The proposed mixed sampling plan can be used in all production industries. This kind of mixed RGS plan is not available in the literature.

Presents a repetitive group sampling plan for three‐attribute classes where items are classified into three categories, namely good, marginal and bad. Derives various performance characteristics of interest to quality control engineers and plan designers through the approach of the Graphic Evaluation and Review Technique (GERT). In order to facilitate the operation and construction of the plan, tabulates Poisson unity values for a useful subset of the proposed plan.

Three thiosemicarbazone derivatives were synthesised: p‐chlorobenzylideneamino thiosemicarbazone, p‐itrobenzylideneamino thiosemicarbazone and p‐N,N ′‐dimethylminobenzylideneamino thiosemicarbazone. The structures of these compounds were characterised by elemental analysis, IR, ¹H NMR and UV spectral measurements. The antifouling properties of the compounds were evaluated through the incorporation of each compound in a marine coating system and testing the system in Alexandria Eastern Harbour water. The results are discussed in the light of the leaching rate of the compounds from their paint films, and their interaction with paint matrix.

This paper aims to reveal the impact of five industry forces (IFs) on implementing input‐based competitive strategies (CSs) and to determine relationship of these CSs on cement plants' environmental performances (EPs).

Data were collected from cement manufacturers in Turkey. This study employed structural equation methodology to examine relationships between IFs, CSs, and EP.

Cement plants with the advantage of low buyer bargaining power, low threat of new entrants, and few rivalries exhibit strong energy and raw material strategies. Also, an advantage of low supplier bargaining power and low threat of substitutes causes competitive raw material strategy. Finally, competitive energy and raw material strategies enhance EP, while competitive human resource strategy has no influence on it.

The model should be tested on other organizations in supply chain. Future researches can also investigate the difference of findings to other industries and in other countries and examine reasons behind hypothesized relationships. Moreover, additional factors may be incorporated into the model. However, a larger participation could provide a different perspective of issues in consideration.

This paper can serve as a valuable framework for top managers to draw the direction of their companies in terms of IFs, CSs, and EP. In this context, practitioners should focus on production inputs to withstand external environment and to experience better EP practices.

A better EP can both enhance sustainability of the overall environment and affect society positively. For such benefits, sustainability of EP should be a subsequent step to be taken to possess long‐lasting societal advantages.

This study is first to propose a model that integrates competitive IFs and input‐based approaches to measure cement plants' EPs. These are relevant issues for competitiveness of cement manufacturers willing to increase their EPs.

The purpose of this work is to introduce an efficient, global second-order accurate and parameter-uniform numerical approximation for singularly perturbed parabolic differential-difference equations having a large lag in time.

The small delay and advance terms in spatial direction are handled with Taylor's series approximation. The Crank–Nicholson scheme on a uniform mesh is applied in the temporal direction. The derivative terms in space are treated with a hybrid scheme comprising the midpoint upwind and the central difference scheme at appropriate domains, on two layer-resolving meshes namely, the Shishkin mesh and the Bakhvalov–Shishkin mesh. The computational effectiveness of the scheme is enhanced by the use of the Thomas algorithm which takes less computational time compared to the usual Gauss elimination.

The proposed scheme is proved to be second-order accurate in time and to be almost second-order (up to a logarithmic factor) uniformly convergent in space, using the Shishkin mesh. Again, by the use of the Bakhvalov–Shishkin mesh, the presence of a logarithmic effect in the spatial-order accuracy is prevented. The detailed analysis of the convergence of the fully discrete scheme is thoroughly discussed.

The use of second-order approximations in both space and time directions makes the complete finite difference scheme a robust approximation for the considered class of model problems.

To validate the theoretical findings, numerical simulations on two different examples are provided. The advantage of using the proposed scheme over some existing schemes in the literature is proved by the comparison of the corresponding maximum absolute errors and rates of convergence.

Uncertainties present in the system parameters and/or external forces play a significant role in the static analysis of structures. Recently, fuzzy numbers have been used to model these uncertainties. It may be noted that when uncertainties are considered only for external loading in terms of type-1 or type-2 fuzzy numbers, the problem is converted to a fuzzy system of linear equations with crisp coefficients. In this regard, the purpose of this research is to propose a new technique to solve the fuzzy system of linear equations with crisp coefficients.

It is very interesting to propose effective techniques to solve such problems. A methodology based on the parametric forms of the type-1 and type-2 fuzzy numbers is used to convert the fuzzy system into interval systems of equations. Further, the concept of double and triple parametric forms is utilised to solve the interval systems.

The proposed technique has been successfully implemented to solve the fuzzy linear system of equations in type-1 as well as type-2 fuzzy environments. Accordingly, sample mathematical problems as well as application problems, namely 8-bar truss structure and uniform rectangular sheet structure, have been solved. Further, present results have been contrasted with the solution obtained by the existing approaches and found to be in good agreement.

To deal with the uncertainty in the external loadings, type-1 and type-2 fuzzy numbers are used here. Also, the approach presented in this work to solve the fuzzy linear system of equations shows the originality of this research.