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This paper aims to present a technique that has been developed to study the wear in the camshaft and tappet. The engine manufacturers use the most suitable materials, lubrication additives and surface coatings to minimize friction in all the components of the engine. Reduced friction results in less wear of critical engine components. The researchers are constantly trying to find an improved lubrication formula which reduces the wear and friction coefficient at a considerably low price. In this regard, the cam follower interface is of much importance because most of the wear occurs in this interface.

The tappets and the cam lobes are analyzed to determine wear. A two-dimensional optical surface profilometer is used to measure the tappet wear, and a high-resolution linear variable differential transformer is used for the measurement of cam lobes. Tests are conducted on Mercedes Benz engine OM 646 under constant camshaft speed, constant inlet lubricant temperature and constant lubricant pressure to study the oil rheology on cam tappet wear.

The results show that the wear occurs on the cam tappet interface, which is almost a linear phenomenon, and it increases with use.

Customized jigs were made to measure wear of camshaft and tappet.

There is a continuous drive in automotive sector to shift from conventional lubricants to environmental friendly ones without adversely affecting critical tribological performance parameters. Because of their favorable tribological properties, chemically modified vegetable oils such as palm trimethylolpropane ester (TMP) are one of the potential candidates for the said role. To prove the suitability of TMP for applications involving boundary-lubrication regime such as cam/tappet interface of direct acting valve train system, a logical step forward is to investigate their compatibility with conventional lubricant additives.

In this study, extreme pressure and tribological characteristics of TMP, formulated with glycerol mono-oleate (GMO), molybdenum dithiocarbamate (MoDTC) and zinc dialkyldithiophosphate (ZDDP), has been investigated using four-ball wear tester and valve train test rig. For comparison, additive-free and formulated versions of polyalphaolefin (PAO) were used as reference. Moreover, various surface characterization techniques were deployed to investigate mechanisms responsible for a particular tribological behavior.

In additive-free form, TMP demonstrated better extreme pressure characteristics compared to PAO and lubricant additives which are actually optimized for conventional base-oils such as PAO, are also proved to be compatible with TMP to some extent, especially ZDDP. During cylinder head tests, additive-free TMP proved to be more effective compared to PAO in reducing friction of cam/tappet interface, but opposite behavior was seen when formulated lubricants were used. Therefore, there is a need to synthesize specialized friction modifiers, anti-wear and extreme pressure additives for TMP before using it as engine lubricant base-oil.

In this study, additive-free and formulated versions of bio-lubricant are tested for cam/tappet interface of direct acting valve train system of commercial passenger car diesel engine for the very test time. Another important aspect of this research was comparison of important tribological performance parameters (friction torque, wear, rotational speed of tappet) of TMP-based lubricants with conventional lubricant base oil, that is, PAO and its formulated version.

This study aims to investigate direct and indirect (via perceived caring climate) links between spiritual leadership and hazing at work in the hospitality context. The authors also test the role of employee interpersonal justice values as a boundary condition.

The authors collected time-lagged data from 441 newcomers and their 441 peers (existing hotel employees) and analyzed the data using structural modeling equation in Mplus (8.6).

The authors found a negative relationship between spiritual leadership and hazing behaviors. Further, perceived caring climate mediated the relationship between spiritual leadership and hazing behaviors. The results also provided support for employee interpersonal justice values as the boundary condition on both the direct relationship between spiritual leadership and perceived caring climate and the indirect relationship between spiritual leadership and workplace hazing.

The authors suggest that there is a value in having organizational leaders who demonstrate spiritual leadership behaviors. This will enhance hospitality employees’ perceptions of a caring climate and undermine their engagement in hazing behaviors.

This study makes an important contribution to the nascent literature on workplace hazing behaviors and spiritual leadership in the hospitality context. The study is also noteworthy because it provides important insights into the antecedents and outcomes of perceived caring climate, an important contextual resource that has imperative implications for hospitality employees’ hazing behaviors.

This study aims to empirically examine the knowledge, social and religious factors effecting the intention to receive COVID-19 vaccination while considering the mediating role of attitude towards COVID-19 vaccination. The research explores how the Islamic ideologies shape Muslims’ knowledge, social and religious beliefs towards COVID-19 vaccination acceptance or refusal.

Theoretically, the study is based on the functional theory of attitudes. The model of the study is comprised of nine variables explaining the attitude and intention towards COVID-19 vaccination. Among nine variables, perceived Islamic religiosity, perceived behavioural control and Halal consciousness among Muslims are explained through the value-expressive function of attitude. Furthermore, the perceived risk of COVID-19, the perceived side effect of COVID-19 vaccination and the perceived efficacy of COVID-19 vaccination are considered in the model based on the utility function of attitude. Moreover, social influence for COVID vaccination, subjective norms and group conformity are abstracted from the social-adjustive function of attitude. This study used a quantitative survey research method to test the hypotheses. A total of 1,000 questionnaires were distributed to non-vaccinated Muslim respondents from five cities in Pakistan. The structural equation modelling (SEM) technique was used to test the relationship among the variables in the proposed model. The partial least square-SEM method explained the variances in the dependent variables. Moreover, to test the structure of data, different statistical tests, including exploratory factor analysis (EFA), factor loadings and average variance extracted, were used with the help of Statistical Package for the Social Sciences (SPSS) and analysis of a moment structures (AMOS) 23.0 version.

Results for direct effect showed a significant negative effect of Islamic religiosity, perceived behavioural control, halal consciousness, perceived side effect of COVID-19 vaccination, social influence, subjective norm and group conformity on attitude towards COVID-19 vaccination. In contrast, insignificant results showed no relationship of perceived risk from COVID-19 infection and perceived efficacy of COVID-19 vaccination with attitude towards COVID-19 vaccination. Results for mediating effect showed the significant negative mediating effect of attitude towards COVID-19 vaccination between Islamic religiosity, perceived behavioural control, halal consciousness, perceived side effect, social influence, subjective norm, group conformity and intention to receive COVID-19 vaccination. While results showed the insignificant mediation of attitude towards COVID-19 between perceived risk from COVID-19 infection, perceived efficacy of COVID-19 vaccination and intention to receive COVID-19 vaccination.

Further studies are required to compare the attitude and intention among the temporary refusal group (those who will consider vaccination the future) and the permanent refusal group (those who will not consider vaccination the future). Comparing Muslim and non-Muslim groups can also explain differences in attitude and intention towards COVID-19 vaccination.

The area of acceptance and refusal of COVID-19 vaccination has been given limited attention in academic literature. Theoretically, this research has proposed a well-defined model to explain the attitude of Muslims towards COVID-19 vaccination. This model can helpf predict the attitude and intentions of Muslims towards vaccination or medicines. Moreover, this research is a unique contribution for the vaccination brands to consider the discussed factors before launching their brand in Muslim countries.

The purpose of the present study is to examine the relationship between spiritual leadership and employees' alienative commitment to the organization, both directly and indirectly, via employee social capital. We also test the role of employee political skill as a boundary condition of the indirect spiritual leadership–alienative commitment link.

Time-lagged data were collected from 491 employees in various manufacturing and service organizations. Data were analyzed using structural modeling equation in Mplus (8.6).

Spiritual leadership was negatively associated with alienative commitment, both directly and indirectly, via social capital. Employee political skill moderated the indirect relationship between spiritual leadership and alienative commitment, such that the relationship was stronger when employee political skill was high (vs low).

The demonstration of spiritual leadership's behaviors by both managers and employees can develop employees' social capital at work, which in turn can reduce employees' negative commitment to the organization. Likewise, improving employees' political skills can help leadership diminish alienative commitment.

The present work contributes to the literature on spiritual leadership by foregrounding how and why spiritual leadership undermines employee alienative commitment to the organization. By doing so, the study also enhances the nomological networks of the antecedents and outcomes of social capital and contributes to the scant literature on negative alienative commitment. Given the prevalence and negative repercussions of alienative commitment for employees' and organizations' productivity and performance, our findings are timely and relevant.

Winglets play a major role in saving fuel costs because they reduce the lift-induced drag formed at the wingtips. The purpose of this paper is to obtain the best orientation of the winglet for the Office National d’Etudes et de Recherches Aérospatiales (ONERA) M6 wing at Mach number 0.84 in terms of lift to drag ratio.

A computational fluid dynamics analysis of the wing-winglet configuration based on the ONERA M6 airfoil on drag reduction for different attack angles at Mach 0.84 was performed using analysis of systems Fluent. First, the best values of cant and sweep angles in terms of aerodynamic performance were selected by performing simulations. The analysis included cant angle values of 30°, 40°, 45°, 55°, 60°, 70° and 75°, while for the sweep angles 35°, 45°, 55°, 65° and 75° angles were used. The aerodynamic performance was measured in terms of the obtained lift to drag ratios.

The results showed that slight alternations in the winglet configuration can improve aerodynamic performance for various attack angles. The best lift to drag ratio for the winglet was achieved at a cant angle of 30° and a sweep angle of 65°, which caused a 5.33% increase in the lift to drag ratio. The toe-out angle winglets as compared to the toe-in angles caused the lift to drag ratio to increase because of more attached flow at its surface. The maximum value of the lift to drag ratio was obtained with a toe-out angle (−5°) at an angle of attack 3° which was 2.53% greater than the zero-toed angle winglet.

This work is relatively unique because the cant, sweep and toe angles were analyzed altogether and led to a significant reduction in drag as compared to wing without winglet. The wing model was compared with the results provided by National Aeronautics and Space Administration so this validated the simulation for different wing-winglet configurations.

This paper aims to study waqf practice in Pakistan with regard to its utilisation in funding for higher educational institutions (HEIs) and investigates waqf raising, waqf management and waqf income utilisation.

The paper is based on the views of 11 participants who are actively involved in the waqf, its raising, management and income utilisation, and is divided into three subcategories: personnel of higher educational waqf institution, personnel of waqf regulatory bodies and Shari’ah and legal experts as well as archival records, documents and library sources.

In Pakistan, both public and private awqaf are existing, but the role of private awqaf is greater in higher education funding. However, due to lack of legal supervision private awqaf is considered as a part of the not-for-profit sector and legitimately registered as a society, foundation, trust or a private limited company. Waqf in Pakistan is more focusing on internal financial sources and waqf income. In terms of waqf management, they have firm guidelines for investing in real estate, the Islamic financial sector and various halal businesses. Waqf uses the income for developmental and operational expenditure, and supports academic activities for students and staff. Waqfs are also supporting some other HEIs and research agencies. Thus, it can be revealed that a waqf can cater a sufficient amount for funding higher educational institutions.

In Pakistan, both public and private awqaf are equally serving society in different sectors, but the role of private awqaf is much greater in funding higher education. Nevertheless, the government treats private awqaf as a part of not-for-profit sector in the absence of a specific legal framework and registers such organisations as society, foundation, trust or private limited company. The waqf in Pakistan mostly relies on internal financial resources and income from waqf assets. As the waqf managers have over the time evolved firm guidelines for investment in real estate, Islamic financial sector and various other halal businesses, and utilisation of waqf income on developmental and operational expenditures, academic activities of students and educational staff, other HEIs and research agencies, it can be proved that the waqf can potentially generate sufficient amount for funding HEIs.

The study presents the waqf as a social finance institution and the best alternative fiscal instrument for funding works of public good, including higher education, with the help of three selected waqf cases. Hence, the paper’s findings offer some generalisations, both for the ummah at large and Pakistan.

The paper makes several policy recommendations for policymakers, legislators and academicians, especially the government. As an Islamic social finance institution, the waqf can help finance higher education anywhere around the world in view of the fact that most countries grapple with huge fiscal deficits and are hence financially constrained to meet growing needs of HEIs.

The study confirms that the waqf can be an alternative source for funding higher education institutions whether it is managed by the government or is privately controlled.

Drawing upon conservation of theory, this study aims to extend the scant literature on the effect of leader-member exchange (LMX) on workplace deviance behaviour (WDB) and adaptive performance by investigating the role of Islamic work ethics as moderators.

A time-lagged and multi-source data of (269 paired responses) of employees working in Islamic banks were used for hypotheses testing.

Taken together, the findings revealed that Leader Member Exchange (LMX) has a positive and significant impact on adaptive performance and is negatively related to employees’ WDB. The results of the moderation effect showed the positive relationship of LMX with adaptive performance and the negative relationship with WDB is stronger for high Islamic work ethics (IWE).

This study provides practical insight that Islamic business ethics plays a significant role in fostering adaptive performance and reducing the deviance behaviour of employees.

To the best of the authors’ knowledge, this is the first study that examined the moderating role of IWE between LMX-adaptive performance and LMX-WDB. This study has also filled the gap of scant literature about the impact of LMX on adaptive performance and WDB.

Abusive supervision is found to influence the workplace negatively but how it predicts knowledge hiding behavior is an area that has not gained due attention in the literature. To this backdrop, this study aims to investigate the effect of abusive supervision on knowledge hiding behavior considering future orientation and Islamic work ethics (IWE) as moderators.

The data from 396 employees, working in both manufacturing and service sectors, is collected through a questionnaire-based survey in two-lags between November 2019 and January 2020.

Structural equation modeling highlighted that a positive relationship exists between abusive supervision and knowledge hiding behavior. Moreover, higher levels of IWE and future orientation are found to weaken the said relationship.

This paper provides practical understandings into extenuating the destructive effects of the dark side of leadership (abusive supervision), a prevalent issue in Asian societies, through the lens of personality (future orientation) and belief (IWE).

This study adds value by investigating the relationship between abusive supervision and knowledge hiding by demonstrating the moderating effects of IWE and future orientation in the context of Pakistan.

The purpose of this paper is to explain the relationship between customer-oriented strategy (COS) and financial performance (FP) of firm, to examine the role of supportive human resource management (HRM) in COS implementation and contribution toward FP of firm. It also examines the mediating role of innovation capability (IC) between COS and FP of firm.

The approach used for this study is quantitative. Data required for testing of hypothesis were gathered from the managers of manufacturing firms of Gujranwala, Pakistan. To conduct the data analysis, structural equation modeling was used.

Findings of this study showed that there is significantly positive relation between COS and FP with the significant positive mediating effects of supportive HRM and IC.

This research has been conducted in manufacturing sector only. So, it is suggested to future researchers to carry out this research in other sectors. Second, this research focused only on IC but there are many other organizational capabilities (OC) that can be used.

This research would be helpful for all firms adopting COS to understand that how to mobilize their HR to accomplish the purpose of strategy. It will enable manufacturing firms to understand and work on IC.

This study is anticipated to add value to the existing literature of strategy process and OC. This study is one of the first to examine IC as mediator between COS and organizational FP so it opens new areas for research.