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The purpose of this paper is to investigate the effect of different viscosity models (Cross and Al-Ma’aiteh) and different printing speeds on the numerical results (e.g. pressure over stencil) of a numerical model regarding stencil printing.

A finite volume model was established for describing the printing process. Two types of viscosity models for non-Newtonian fluid properties were compared. The Cross model was fitted to the measurement results in the initial state of a lead-free solder paste, and the parameters of a Al-Ma’aiteh material model were fitted in the stabilised state of the same paste. Four different printing speeds were also investigated from 20 to 200 mm/s.

Noteworthy differences were found in the pressure between utilising the Cross model and the Al-Ma’aiteh viscosity model. The difference in pressure reached 33-34% for both printing speeds of 20 and 70 mm/s and reached 31% and 27% for the printing speed of 120 and 200 mm/s. The variation in the difference was explained by the increase in the rates of shear by increasing printing speeds.

Parameters of viscosity model should be determined for the stabilised state of the solder paste. Neglecting the thixotropic paste nature in the modelling of printing can cause a calculation error of even approximately 30%. By using the Al-Ma’aiteh viscosity model over the stabilised state of solder pastes can provide more accurate results in the modelling of printing, which is necessary for the effective optimisation of this process, and for eliminating soldering failures in highly integrated electronic devices.

The purpose of this paper is to present the establishment of a computational fluid dynamics model for investigating different non-Newtonian rheological models of solder pastes by simulating solder paste viscosity measurement. A combined material model was established which can follow the measured, apparent viscosity values with lower error.

The model included a parallel plate arrangement of rheometers. The diameter of the plate was 50 mm, whereas the gap between the plates was 0.5 mm. Only one quarter of the plate was modelled to enable using fine enough mesh, while keeping the calculation time low. Non-Newtonian properties were set using user defined function in Ansys, based on the Cross and Carreau–Yasuda material models. The viscosity values predicted by the mathematical models were compared to measured viscosity values of different types of solder pastes.

It was found that the Cross model predicts the apparent viscosity with a relatively high error (even approximately 50 per cent) at lower shear rates, whereas the Carerau–Yasuda model has higher errors at higher shear rates. The application of the proposed, combined model can result in a much lower error in the apparent viscosity between the calculated and measured viscosity values.

The error of Cross and Carreau–Yasuda material models has not been investigated yet in details. The proposed, combined material model can be applied for subsequent simulations via the described UDF, e.g. in the numerical modelling of the stencil printing. This can result in a more accurate modelling of the stencil printing process, which is inevitable considering the printing of solder paste for today fine-pitch, small size components.

The conflict between Iran and Iraq is not new; it dates from long before September 1980. In fact, the origins of the current war can be traced to the battle of Qadisiyah in Southern Iraq in 637 A.D., a battle in which the Arab armies of General Sa'd ibn Abi Waqqas decisively defeated the Persian army. In victory, the Arab armies extended Islam east of the Zagros Mountains to Iran. In defeat, the Persian Empire began a steady decline that lasted until the sixteenth century. However, since the beginning of that century, Persia has occupied Iraq three times: 1508–1514, 1529–1543, and 1623–1638. Boundary disputes, specifically over the Shatt al‐Arab Waterway, and old enmities caused the wars. In 1735, belligerent Iranian naval forces entered the Shatt al‐Arab but subsequently withdrew. Twenty years later, Iranians occupied the city of Sulimaniah and threatened to occupy the neighboring countries of Bahrain and Kuwait. In 1847, Iran dominated the eastern bank of the Shatt al‐Arab and occupied Mohamarah in Iraq.

This paper aims to compare and contrast the concept of conventional futures contract from the Islamic law of contract perspectives. The underlying theory and practice of Islamic finance is based on the principles of Islamic law of contract. Although the necessity of derivative instruments such as the case with futures contract is essential for developments in Islamic finance, the permissibility of using these instruments still remains a debatable issue.

The paper discusses arguments for and against using derivative instruments as in futures, for example, in light with the Qur’an and Sunnah (the Prophet’s traditions), as well as the views of classical scholars, jurists and contemporary researchers. Arguments for and against are analysed systematically to derive a logical conclusion.

The study finds that majority scholars consider futures contracts as non-compliant with the Islamic law due to the fact that selling something that does not exist, deferment in the both counter values, gharar or ambiguity and excessive risk taking, pure speculation and sale of one debt for another.

The study focuses narrowly on conventional futures contract. Analysing other financial derivative contracts could be a future research endeavour.

The study has so far found the verdict of impermissibility of conventional futures contract in its current form as has been argued by majority scholars in the premise that they do not comply with the Islamic law. Policymakers and industry practitioners need to take this opinion of majority scholars while developing new Islamic financial derivatives.

To the best of the author's knowledge, the present research is the first attempt so far that explained the validity of conventional futures by analysing arguments of classical and contemporary jurists, scholars and researchers.

Waqf has the quality of perpetuity so waqf properties cannot be sold, bought or given as a gift to others. Therefore, it is necessary to make sure that the property is fully used and properly managed by the Malaysian Islamic councils. To properly manage these properties, it is essential for the councils to have a proper reporting. Unfortunatley, this is not the case in the present situation for waqf. It was found that there is a lack of reporting on waqf matters. The purpose of this paper is to explore how the Islamic governance can contribute to the sufficient and adequate of waqf reporting.

This paper described what is being practised at present for waqf reporting. A series of Islamic governance literature was proposed in reinforcing waqf reporting.

This paper fulfils a gap in prior research by discussing several systems in Islamic governance to achieve transparency in waqf reporting. The findings of this paper may provide a significant contribution to any organisation that act as a trustee for waqf.

This paper provides an opportunity for further theoretical approach in defining and describing the role of governance in the reinforcement of waqf reporting. The paper has recommended several strategies towards better governance in Islamic council, and these suggestions can be offered to the councils for improvement.

This research will be of interest to policy makers, especially Government and State Government. Given the current debate in Malaysia on the most appropriate forms of regulation for the Islamic sector, this study aims to provide valuable insights into the role of Islamic governance in the system of regulation.

This paper examined several governance system in Islamic governance to be applied in any Islamic organisation. This paper specifically deals governance issue that should be practised by present councils to prevent lack in waqf reporting. This system discusses the ways Islamic councils should perform since the system was originally implemented by a previous, distinguished caliph, Umar Al-Khattab.

This study aims to systematically review the literature on modern Islamic finance transactions pertaining to Gharar dimensions. Gharar is defined as uncertainty that potentially leads to ambiguities and conflicts in contracts.

The articles reviewed in this study consisted of 13 articles related to Gharar published between 2013 and 2022. All selected articles were empirically and descriptively searched using specific keywords and strings. The main sources for this study were Scopus and Web of Science (WoS), whereas Google Scholar was a supportive database.

The review found that the dimensions that discussed previous research were trying their best to elaborating Gharar in modern financial transactions. They also demonstrate that rigorous study and deployment of the definition remain in the context defined by jurisprudence scholars. The focus of recent studies pertaining to Gharar is derivatives products that indicate high possibility of uncertainty in its operation.

This method relies heavily on the accessed database, namely, Scopus and WoS, also referred to the articles as recommended by the databases. Furthermore, the criteria of inclusion and exclusion of papers outlined by the authors deemed as an intrinsic limitation in writing systematic literature review.

To the best of the authors’ knowledge, this paper is original in its nature whereby the scholars had different comprehension on how Gharar exists in transaction but they still centred in its original meaning of uncertainty. As a result, this paper also realized how Gharar were interpreted differently relied on the contract’s nature and behaviour. In addition, this paper is expected to contribute to understand how Gharar been interpreted in modern finance transactions and finally reached to the point that further research is needed in establishing Gharar parameter for each contract in Islamic commercial law.

This study aims to analyse the Shariah issues in the implementation of tawarruq contract in the Islamic profit rate swap (IPRS) instrument in Malaysia.

This is a qualitative study in applying data analysis and semi-structured interview approaches. Data was collected from various documents including journals, articles and past studies conducted by scholars. To achieve the purpose of this study, the data is analysed based on thematic analysis.

The study found several Shariah issues regarding the implementation of tawarruq contract in the IPRS instruments, which have remained a dispute amongst the Islamic financial scholars such as its profit-making purpose, encouragement of debt, impediment of shared risk concept, disputed underlying assets, a deception towards allowing riba and dual agency.

This study recommends several improvements such as the establishment of a neutral agency that does not represent any banking institution to manage the tawarruq contract commodity purchase from Bursa Suq al-Sila’ (BSAS). In addition, a neutral agency can provide aid in terms of transaction facility or at least consultation service for clients to enable them to conduct the commodity transactions independently.

Moreover, guidelines should be established on the separation of the deadline to sign the agreement of appointment of a bank as the commodity purchase agent and the agreement of appointment of the bank as the commodity sale agent on behalf of clients. All transactions related to tawarruq contract commodity must be done through BSAS. The regulators and industry experts may create a guideline for the IPRS based on the issues and recommendations that have been discussed in this study.

On the basis of the analysis of the criticisms and issues in the implementation of tawarruq contract in the IPRS instrument, the current study found that an intermediating institution is allowed to gain profits from transactions conducted so long as they are based on Shariah principles of contract in Islam. As there is no parameter specifically for IPRS, thus the suggested parameter can be used by policymakers such as the Central Bank of Malaysia to ensure the industry complies with Shariah principles.