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This paper reports on the reliability data analysis and modelling of offshore oil platform plant. We first analysed the effectiveness of preventive maintenance to the plant concerned, and then identified the key sub‐units and major preventive maintenance activities to be modelled. A modelling technique called the delay time is then used to determine the optimal periodic inspection intervals. The analysis showed that preventive maintenance is generally effective, but a slight decrease of the periodic inspection intervals is favourable.

This paper aims to address the effect of inspection intervals on cost function in condition‐based maintenance (CBM) and show how selecting an appropriate inspection scheme may reduce the cost associated to a CBM program.

In CBM, replacement policy is often defined as a threshold for replacement or leaving an item in operation until next inspection, depending on monitoring information. The control limit replacement policy framework, already reported by some research referred to in this paper, is utilized to determine the optimal replacement threshold. Having released the assumption that the inspections are performed at fixed and constant intervals, an iterative procedure is proposed to evaluate alternative inspection schemes and their associated total average cost of replacements and inspections.

The paper proposes an approach in which preventive and failure replacement costs as well as inspection cost are taken into account to determine the optimal replacement policy and an age‐based inspection scheme such that the total average cost of replacements and inspections is minimized.

In many practical situations where CBM is implemented, e.g. manufacturing processes, inspections require labor, specific test devices, and sometimes suspension of the operations. Thus, when inspection cost is considerable, by applying the proposed approach, one can obtain an inspection scheme that reduces the cost.

Using the approach proposed in the paper, a cost‐effective age‐based inspection scheme for a system under CBM is determined.

This study aims to explore how the three types of human resource (HR) practices, encapsulated in the ability, motivation and opportunity (AMO) model, foster a learning organizational culture (LOC). In doing so, the authors evaluate the centrality of knowledge sharing (KS) in mediating this relationship.

A quantitative survey is undertaken to collect data from managers working in organizations operating in the UK. The authors use several statistical techniques to assess the psychometric properties of the measures and test the hypotheses using multiple regression executed with Preacher and Hayes’ Process macro.

The findings show that the AMO HR practices significantly facilitate the development of a LOC in the workplace, and KS among organizational members amplifies the effects of these HR practices in the process.

A LOC functions as an important source of organizational performance and effectiveness. It enhances the absorptive capacity of the organization to capture, share and transfer knowledge to optimize work. Hence, developing a culture that nurtures organizational learning could be a priority for managing HR. This study, therefore, extends the understanding of the role of AMO HR practices in fostering a learning culture – thus, providing managers with the essential knowledge to improve performance. The study also enriches the literature on HR practices, KS and LOC by integrating these three variables into a unifying framework.

This study aims to examine the influence of perceived organizational support (POS) on boundary-spanning behaviors (BSBs) among frontline employees in the hospitality industry. It also considered perceived supervisory support (PSS) as a moderating factor within a conceptual model.

Data were gathered from 651 full-time hospitality employees across 12 hotels in China. The analysis of the data used confirmatory factor analysis and structural equation modeling.

The findings revealed that POS influences hospitality boundary spanners’ BSBs, specifically external representation (ER), internal influence (II) and service delivery (SD). In addition, PSS moderates the relationship between POS and these frontline employees’ behaviors.

This study offers practical strategies for hospitality professionals to enhance frontline employees’ BSBs and foster supportive workplaces that drive employee excellence. These strategies encompass cultivating a supportive organizational culture, implementing supportive measures, fostering a sense of belonging among employees and ensuring supervisors’ well-being and competence in supporting their teams during daily interactions. These actions effectively motivate customer-contact employees to excel in their performance.

Fostering a helpful attitude in frontline employees is crucial for service firms’ success. Hospitality organizations must provide support to achieve this. Few studies have explored how organizational support contributes positively to the BSBs of customer-contact employees. This study goes beyond oversimplification and delves into the nuanced interplay between perceived support (POS and PSS) and hospitality frontline employees’ BSBs, focusing on ER, II and SD. The moderated mediating model enhances the understanding of support dynamics in the organizational context.

The purpose of this paper is to investigate a three-dimensional boundary layer flow with considering heat and mass transfer on a nonlinearly stretching sheet by using a novel operational-matrix-based method.

The partial differential equations that governing the problem are converted into the system of nonlinear ordinary differential equations (ODEs) with considering suitable similarity transformations. A direct numerical method based on the operational matrices of integration and product for the linear barycentric rational basic functions is used to solve the nonlinear system of ODEs.

Graphical and tabular results are provided to illustrate the effect of various parameters involved in the problem on the velocity profiles, temperature distribution, nanoparticle volume fraction, Nusselt and Sherwood number and skin friction coefficient. Comparison between the obtained results, numerical results based on the Maple's dsolve (type = numeric) command and previous existing results affirms the efficiency and accuracy of the proposed method.

The motivation of the present study is to provide an effective computational method based on the operational matrices of the barycentric cardinal functions for solving the problem of three-dimensional nanofluid flow with heat and mass transfer. The convergence analysis of the presented scheme is discussed. The benefit of the proposed method (PM) is that, without using any collocation points, the governing equations are converted to the system of algebraic equations.

Performance problems in the public sector (PS) necessitate adaptation due to the sector’s uniqueness. Purposeful leadership (PL) may resolve PS adaptive performance (AP) problems. However, there is a paucity of research on the influence of PL on AP. Using data from three large PS organisations in Ghana, this research explores the relationship between PL and AP through job satisfaction (JS) and organisational identification (OI). It also explores the moderating effect of organisational integrity (IN) on the PL–JS and PL–OI relationships.

This paper created and tested a research model using the responses of 875 public servants in Smart PLS 4. Contract fulfilment and perceived organisational support functioned as control factors influencing JS (an intervener). Perceived procedural justice and psychological need satisfaction serve as control factors for OI (another intervener). Age, sex, tenure, education and job position were used as control variables in AP. To assess the role of moderation, we utilised the product indicator approach, and to estimate the role of mediation, we used variance accounted for (VAF). A significance level of 5% was established.

As anticipated, this study found that PL and AP had a significantly positive connection (t = 2.229, p = 0.000, β = 0.138). Both JS (VAF = 27.37%) and OI (VAF = 39.21%) partially mediated this connection. IN positively moderated the PL–JS (t = 4.249, p = 0.000, β = 0.165) and PL–OI (t = 3.704, p = 0.002, β = 0.099) connections.

This paper provides a theoretical and empirical understanding of the PL–AP relationship, how this relationship is facilitated and how the PL–JS and PL–OI relationships are strengthened. It provides a roadmap for upcoming scholars to test the hypotheses in diverse PS contexts globally to broaden the field of leadership. It will be insightful to show how JS and OI jointly mediate this relationship and the potential mediating role of job embeddedness in further studies.

Human resource (HR) practices in PS organisations, such as selecting, leadership enhancement initiatives, promotions, training and performance evaluations, must be guided by a “values-driven strategy” if leadership is to find, cultivate and keep employees capable of devising innovative strategies to manage unforeseen circumstances at work. The leaders are required to demonstrate the values of their organisations in order to set up a role model.

This study highlights the obstacles that purposeful leaders have the potential to mitigate, as well as the prospects that they might offer. It shows the essence for PS organisations to uphold and maintain high integrity standards as their hallmark.

This paper is the first to create and test a research model that shows the relationship between PL and AP. It also shows the different mechanisms (JS and OI) that make this effect possible, as well as the good work environment (i.e. IN) that allows the PL–JS and PL–OI relationships to grow.

(1) A mathematical model for the Hybrid nanofluids flow is used as carriers for delivering drugs. (2) The flow conditions are controlled to enable drug-loaded nanofluids to flow through the smaller gap between the two tubes. (3) Hybrid nanofluids (HNFs) made from silver (Ag) and titanium dioxide (TiO₂) nanoparticles are analyzed for applications of drug delivery. (Ag) and (TiO₂) (NPs) are suitable candidates for cancer treatment due to their excellent biocompatibility, high photoactivity, and low toxicity. (4) The new strategy of artificial neural networks (ANN) is used which is machine-based and more prominent in validation, and comparison with other techniques.

The two Tubes are settled in such a manner that the gap between them is uniform. The Control Volume Finite Element Method; Rk-4 and Artificial Neural Network (ANN).

(1) From the obtained results it is observed that the dispersion and distribution of drug-loaded nanoparticles within the body will be improved by the convective motion caused by hybrid nanofluids. The effectiveness and uniformity of drug delivery to target tissues or organs is improved based on the uniform flow and uniform gap. (2) The targeting efficiency of nanofluids is further improved with the addition of the magnetic field. (3) The size of the cylinders, and flow rate, are considered uniform to optimize the drug delivery.

(1)The flow phenomena is considered laminar, one can use the same idea through a turbulent flow case. (2) The gap is considered uniform and will be interesting if someone extends the idea as non-uniform.

(1) To deliver drugs to the targeted area, a suitable mathematical model is required. (2) The analysis of hybrid nanofluids (HNFs) derived from silver (Ag) and titanium dioxide (TiO₂) nanoparticles is conducted for the purpose of drug delivery. The biocompatibility, high photoactivity, and low toxicity of (Ag) and (TiO₂) (NPs) make them ideal candidates for cancer treatment. (3) Machine-based artificial neural networks (ANN) have a new strategy that is more prominent in validation compared to other techniques.

The drug delivery model is a useful strategy for new researchers. (1) They can extend this idea using a non-uniform gap. (2) The flow is considered uniform, the new researchers can extend the idea using a turbulent case. (3) Other hybrid nanofluids flow, in the same model for other industrial usages are possible.

All the obtained results are new. The experimental thermophysical results are used from the existing literature and references are provided.

Taking into consideration the current human need for agricultural produce such as rice that requires water for growth, the optimal consumption of this valuable liquid is important. Unfortunately, the traditional use of water by humans for agricultural purposes contradicts the concept of optimal consumption. Therefore, designing and implementing a mechanized irrigation system is of the highest importance. This system includes hardware equipment such as liquid altimeter sensors, valves and pumps which have a failure phenomenon as an integral part, causing faults in the system. Naturally, these faults occur at probable time intervals, and the probability function with exponential distribution is used to simulate this interval. Thus, before the implementation of such high-cost systems, its evaluation is essential during the design phase.

The proposed approach included two main steps: offline and online. The offline phase included the simulation of the studied system (i.e. the irrigation system of paddy fields) and the acquisition of a data set for training machine learning algorithms such as decision trees to detect, locate (classification) and evaluate faults. In the online phase, C5.0 decision trees trained in the offline phase were used on a stream of data generated by the system.

The proposed approach is a comprehensive online component-oriented method, which is a combination of supervised machine learning methods to investigate system faults. Each of these methods is considered a component determined by the dimensions and complexity of the case study (to discover, classify and evaluate fault tolerance). These components are placed together in the form of a process framework so that the appropriate method for each component is obtained based on comparison with other machine learning methods. As a result, depending on the conditions under study, the most efficient method is selected in the components. Before the system implementation phase, its reliability is checked by evaluating the predicted faults (in the system design phase). Therefore, this approach avoids the construction of a high-risk system. Compared to existing methods, the proposed approach is more comprehensive and has greater flexibility.

By expanding the dimensions of the problem, the model verification space grows exponentially using automata.

Unlike the existing methods that only examine one or two aspects of fault analysis such as fault detection, classification and fault-tolerance evaluation, this paper proposes a comprehensive process-oriented approach that investigates all three aspects of fault analysis concurrently.

The purpose of this paper is to explore new reduced form of the (3 + 1)-dimensional generalized B-type Kadomtsev-Petviashvili (BKP) equation by considering its bilinear equations, derived from connection between the Hirota’s transformation and Bell polynomials.

Based on the bilinear form of new reduced form of the (3 + 1)-dimensional generalized BKP equation, lump solutions with sufficient and necessary conditions to guarantee analyticity and rational localization of the solutions are discovered. Also, extended homoclinic approach is applied to considered equation for finding solitary wave solutions.

A class of the bright-dark lump waves are fabricated for studying different attributes of (3 + 1)-dimensional generalized BKP equation and some new exact solutions including kinky periodic solitary wave solutions and line breathers periodic are also obtained by Following the extended homoclinic approach.

The paper presents that the implemented methods have emerged as a promising and robust mathematical tool to manage (3 + 1)-dimensional generalized BKP equation by using the Hirota’s bilinear equation.

By considering important characteristics of lump and solitary wave solutions, one can understand the shapes, amplitudes and velocities of solitons after the collision with another soliton.

The analysis of these higher-dimensional nonlinear wave equations is not only of fundamental interest but also has important practical implications in many areas of mathematical physics and ocean engineering.

To the best of the authors’ knowledge, the acquired solutions given in various cases have not been reported for new reduced form of the (3 + 1)-dimensional generalized BKP equation in the literature. These obtained solutions are advantageous for researchers to know objective laws and grab the indispensable features of the development of the mathematical physics.

This paper aims to study the colour stability of chlorophyll and the effect of copper (II) nitrate – Cu(NO₃)₂ – as an additive in natural dye coating films after being exposed to ultraviolet-A (UV-A).

The natural dye was extracted from the leaves of Cassia alata L. using absolute ethanol as the solvent. The extract was divided into two parts and, one of it was added with 3 wt.% Cu(NO₃)₂ as an additive. The polymer blend of poly(methyl methacrylate) (PMMA) and acrylic polyol was used as the coating binder. Both parts of the dye with and without additive were mixed with the blended polymer in a specific ratio. The resulted mixtures were applied as coating films on glass substrates. The colour stability of the coating films on exposure to UV-A with the time of exposure was observed with Commission internationale de l’éclairage (CIE) L*a*b* colour coordinates. The hidden power by the means of reflectivity and glossiness of the coatings was also studied. Statistical standard deviation (STD) was used to analyse the data.

The test showed that the coating films containing Cu(NO₃)₂ had smaller colour differences, (ΔE*) indicating higher colour stability. The analysis on hidden power also showed that the coating film with Cu(NO₃)₂ was 1.6 times more stable than the film without additive. All the measurements in this study were observed within 35 days of duration.

This paper implies the potential of using natural dye extracted from Cassia alata L. leaves as a stable dye colourant for coating applications.

The coating film developed in this study is suitable for glass substrate applications.

A new method of preparing solvent-based coating film from PMMA–acrylic polyol with chlorophyll colourant is introduced in this study.