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The purpose of this paper is to describe development and application of an iterative learning control (ILC) scheme for a tracking problem. The control objective is to achieve accurate tracking of a desired trajectory which is the path taken by a laser beam.

It involves formulating an ILC scheme in two‐dimensional (2D) representation on mathematical model of two degrees of freedom platform. The scheme was tested and fine tuned with the help of simulation results on that model. Subsequently, an experimental setup was prepared by mounting a camera on a six degree of freedom hexapod, M‐850 from Physik Instrumente. The experimental setup was made to track an arbitrarily positioned laser spot on a screen. For this purpose, a simple image processing module was also developed. The underlying algorithm implemented learning and tracking modes.

The tracking performance of the scheme is impressive. The simulations as well as practical results show that the scheme is robust and simple to implement.

The limitation is the time spent in learning mode before the control function is applied to the system under consideration. This, however, is an inherent aspect in any ILC scheme.

Its application can be in manufacturing processes, robotics, target tracking and even in bio engineering where growth of some specific bacteria population could also be tracked.

Little work, with practical implementations, has been reported in ILC. The authors perceive that this scheme has the potential to simplify a great number of control problems especially in the field of robotics and trajectory tracking.

The main purpose of this study is to analyze the heat transfer phenomena in a dynamically bulging enclosure filled with Cu-water nanofluid. This study examines the convective heat transfer process induced by a bulging area considered a heat source, with the enclosure's side walls having a low temperature and top and bottom walls being treated as adiabatic. Various factors, such as the Rayleigh number (Ra), nanoparticle volume fraction, Darcy effects, Hartmann number (Ha) and effects of magnetic inclination, are analyzed for their impact on the flow behavior and temperature distribution.

The finite element method (FEM) is employed for simulating variations in flow and temperature after validating the results. Solving the non-linear partial differential equations while incorporating the modified Darcy number (10⁻³ ≤ Da ≤ 10⁻¹), Ra (10³ ≤ Ra ≤ 10⁵) and Ha (0 ≤ Ha ≤ 100) as the dimensionless operational parameters.

This study demonstrates that in enclosures with dynamically positioned bulges filled with Cu-water nanofluid, heat transfer is significantly influenced by the bulge location and nanoparticle volume fraction, which alter flow and heat patterns. The varying impact of magnetic fields on heat transfer depends on the Rayleigh and Has.

The geometry configurations employed in this research have broad applications in various engineering disciplines, including heat exchangers, energy storage, biomedical systems and food processing.

This research provides insights into how different shapes of the heated bulging area impact the hydromagnetic convection of Cu-water nanofluid flow in a dynamically bulging-shaped porous system, encompassing curved surfaces and various multi-physical conditions.

Offshore industries encounter severe production downtime due to high liquid carryovers in the T-junction. The diameter ratio and flow regime can significantly affect the excess liquid carryovers. Unfortunately, regular and reduce T-junctions have low separation efficiencies. Ansys as a commercial computational fluid dynamics (CFD) software was used to model and numerically inspect a novel diverging T-junction design. The purpose of diverging T-junction is to merge the specific characteristics of regular and reduced T-junctions, ultimately increasing separation efficiency. The purpose of this study is to numerically compute the separation efficiency for five distinct diverging T-junctions for eight different velocity ratios. The results were compared to regular and converging T-junctions.

Air-water slug flow was simulated with the help of the volume of the fluid model, coupled with the K-epsilon turbulence model to track liquid-gas interfaces.

The results of this study indicated that T-junctions with upstream and downstream diameter ratio combinations of 0.8–1 and 0.5–1 achieved separation efficiency of 96% and 94.5%, respectively. These two diverging T-junctions had significantly higher separation efficiencies when compared to regular and converging T-junctions. Results also revealed that over-reduction of upstream and downstream diameter ratios below 0.5 and 1, respectively, lead to declination in separation efficiency.

The present study is constrained for air and water as working fluids. Nevertheless, the results apply to other applications as well.

The proposed T-junction is intended to reduce excessive liquid carryovers and frequent plant shutdowns. Thus, lowering operational costs and enhancing separation efficiency.

Higher separation efficiency achieved by using diverging T-junction enabled reduced production downtimes and resulted in lower maintenance costs.

A novel T-junction design was proposed in this study with a separation efficiency of higher than 90%. High separation efficiency eliminates loss of time during shutdowns and lowers maintenance costs. Furthermore, limitations of this study were also addressed as the lower upstream and downstream diameter ratio does not always enhance separation efficiency.

In plethora of petroleum, chemical and heat transfer applications, T-junction is often used to partially separate gas from other fluids, to reduce work burden on other separating equipment. The abundance of liquid carryovers from the T-junction side arm is the cause of production downtime in terms of frequent tripping of downstream equipment train. Literature review revealed that regular and reduced T-junctions either have high peak liquid carryovers (PLCs) or the liquid appears early in the side arm [liquid carryover threshold (LCT)]. The purpose of this study is to harvest the useful features of regular and reduced T-junction and analyze diverging T-junction having upstream and downstream pipes.

Volume of fluid as a multiphase model, available in ANSYS Fluent, was used to simulate air–water slug flow in five diverging T-junctions for eight distinct velocity ratios. PLCs and LCT were chosen as key performance indices.

The results indicated that T (0.5–1) and (0.8–1) performed better as low liquid carryovers and high LCT were achieved having separation efficiencies of 96% and 94.5%, respectively. These two diverging T-junctions had significantly lower PLCs and high LCT when compared to other three T-junctions. Results showed that the sudden reduction in the side arm diameter results in high liquid carryovers and lower LCT. Low water and air superficial velocities tend to have low PLC and high LCT.

This study involved working fluids air and water but applies to other types of fluids as well.

The novel T-junction design introduced in this study has significantly higher LCT and lower PLC. This is an indication of higher phase separation performance as compared to other types of T-junctions. Because of lower liquid take-offs, there will be less frequent downstream equipment tripping resulting in lower maintenance costs. Empirical correlations presented in this study can predict fraction of gas and liquid in the side arm without having to repeat the experiment.

Maintenance costs and production downtime can be significantly reduced with the implication of diverging T-junction design.

The presented study revealed that the diameter ratio has a significant impact on PLC and LCT. It can be concluded that novel T-junction designs, T2 and T3, achieved high phase separation; therefore, it is favorable to use in the industry. Furthermore, a few limitations in terms of diameter ratio are also discussed in detail.

The policy approach in Pakistan with regard to combating the informal economy has remained quite myopic and skewed in its reliance on measures informed by the rational economic-actor theory as opposed to the social-actor approach. Thus, this study attempts to evaluate and synthesise the two alternative policy approaches and formulate a more theoretically integrative understanding of the subject.

The authors gather data from 600 micro-entrepreneurs operating in the retail and wholesale sector of Lahore, Pakistan, which is then analysed using an ordered logit regression technique.

In contrast to more developed countries, the finding here is that higher perceived penalties have a highly significant and positive impact on the level of formality of Pakistani micro-entrepreneurs. The perceived risk of detection, meanwhile, has only a moderately significant impact on the micro-entrepreneurs level of formality. Likewise, the level of vertical and horizontal trust has a positive but moderately significant impact on the level of formality. Nonetheless, both the vertical and horizontal trust exhibit a very significant moderating effect on the relationship between the use of penalties and the level of formality, that is, the higher the level of trust that the micro-entrepreneurs have in the state and other businesses, the lower is the effectiveness of punitive measures.

Deterrence is an effective way to enhance the level of formality in the case of the Pakistani context. Nonetheless, the authors imply that without building trust, this overreliance on punitive and detective measures can actually be counter-productive. A combined and congruent (not sequential) use of voluntary compliance measures is thus warranted.

It is a unique attempt to evaluate and synthesise the global policy theorisations in a non-mainstream and antagonistic climate, such as Pakistan.

This study aims to examine the mediating and moderating roles of cognitive trust and organizational culture in the relationship between leadership and employee task performance and turnover intention.

Data were collected from 543 employees through a survey from the Islamic banking sector in Pakistan. Structural equation modelling (partial least squares) was used to estimate the effect.

The results demonstrate that cognitive trust plays a positive and significant mediating role between leadership and task performance (O = 0.064, T = 2.005, p = 0.028). Moreover, there is a negative relationship between leadership and employee turnover intention with the mediation of cognitive trust (O = −0.061, T = 1.976, p = 0.021). In addition, organizational culture plays a significant moderating role between cognitive trust and employee task performance (O = 0.014, T = 2.141, p = 0.038).

The results emphasize the critical role of organizational culture and cognitive trust in amplifying or reducing the impact of leadership on employee attitudes. This offers managers and leaders practical insights to boost employee performance and reduce turnover.

To the best of the authors’ knowledge, this study is unique in that it seeks to advance understanding of social exchange theory management by examining the moderated-mediation frameworks in the interaction between leadership and specific aspects of employee attitudes.

The prime objective of this study is to examine the impact of sight cues and corporate social responsibility (CSR) activities of the Islamic banks on loyalty by improving the corporate image (CI) of the Islamic banks. This study also examines the mediating effect of a CI along with moderating impact of religion and collectivism on loyalty.

The data were obtained through the purposive sampling method by distributing questionnaires among the customers of Islamic banks. A total of 550 questionnaires were surveyed from six full-fledged commercial Islamic banks and eight Islamic windows of the commercial bank in Pakistan using variance-based structural equation modelling (partial least squares) to test the hypothesis.

The results of the study reflected that sight cues and CSR activities have a significant impact on CI and keeping the customer’s loyalty. Additionally, religion and collectivism also moderate the relationship between CI and loyalty.

From a managerial perspective, the study finding exhibits the significant effect, both directly and indirectly, of religiosity on the loyalty intention of the customers of Islamic banks. Hence, persuading the client that the bank is in complete compliance with (Shariah) will forestall their clients switching to another bank.

This study is unique in its nature because it revealed the factors that lead to customer loyalty towards Islamic banks. The study found sight cues and CSR are the new indicators used to build CIs of Islamic banks.

This study aims to analyze the imbalances in the public finance structure of Pakistan’s economy and highlight the need for comprehensive reforms. Specifically, it aims to contribute to the empirical literature by analyzing the relationship between fiscal vulnerability, financial stress and macroeconomic policies in Pakistan’s economy between 1971 and 2020.

The study develops an index of fiscal vulnerability, an index of financial stress and an index of macroeconomic policies. The fiscal vulnerability index is based on the patterns of fiscal indicators resulting from past trends of the selected variables in Pakistan’s economy. The financial stress in Pakistan is caused from the financial disorders that are acknowledged in the composite index, which is based on variables with the potential to indicate periods of stress stemming from the foreign exchange market, the securities market and the monetary policy components. The macroeconomic policies index is developed to analyze the mechanism through which fiscal vulnerability and financial stress have influenced macroeconomic policies in Pakistan. The causal association between fiscal vulnerability, financial stress and macroeconomic policies is analyzed using the auto-regressive distributive lags approach.

There exists a long-run relationship between the three indices, and a bi-directional causality between fiscal vulnerability and macroeconomic policies.

This study contributes to the development of a fiscal monitoring mechanism, which has the basic purpose of analyzing the refinancing risk of public liabilities. Moreover, it focuses on fiscal vulnerability from a macroeconomic perspective. The study tries to develop a framework to assess fiscal vulnerability in light of “The Risk Octagon” theory, which focuses on three risk components: fiscal variables, macroeconomic-disruption-associated shocks and non-fiscal country-specific variables. The initial contribution of this work to the literature is to develop a framework (a fiscal vulnerability index, financial stress index and macroeconomic policies index) for effective and result-oriented macro-fiscal surveillance. Moreover, empirical literature emphasized and advised developing countries to develop their own capacity mechanisms to assess their fiscal vulnerability in light of the IMF guidelines regarding vulnerability assessments. This study thus attempts to fulfill the said gap identified in literature.

Islamic Banking has been in the limelight since the recession of 2008. Although around for a long time, it is enjoying a renaissance of sorts. This case provides an introduction.

EMBA and/or MBA introduction to banking, senior semester undergraduate, specialization in Islamic Banking.

This case is written in the form of an interview with Meezan Bank, one of the leading financial institutions in the Islamic banking sector. It is based on primary as well as secondary data obtained via interviews and documentary analysis.

This is an analytical case and not a decision-making one. The main theme of the case revolves around analysing what Islamic banking is, the challenges that Meezan has faced, the pros and cons of doing business this way and the future issues it can face.

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CSS 7: Management Science.