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The purpose of this paper is to present the dependence of capacitive sensing of organic vapours by porous silicon (PS) on its molecular structure for the realization of a organic vapour sensor, compatible with existing silicon technology, with desired miniaturization and selectivity.

The method introduces large surface area of PS obtained by electrochemically etching of silicon wafer for characterization of organic vapours through capacitive sensing.

The method provides a comparative study of sensor response for organic vapour molecules of different structures and leads to an insight into the sensing mechanism.

The surface of PS has been stabilized by thermal oxidation process.

The method is useful for the development of a simple, cost‐effective sensor for selective gas analysis.

The result is an outcome of regular experimental work carried out to observe the capacitive sensing behavior of PS for different organic vapours.

The purpose of this paper is to investigate the hydromagnetic third-grade non-Newtonian fluid flow and heat transfer between two coaxial pipes with a variable radius ratio.

To solve the approximate nonlinear and linear problems with variable coefficients, a trial function was applied. Methods include collocation, least square and Galerkin that can be applied for obtaining these coefficients.

It is revealed that an increase of the non-Newtonian parameter, Hartmann number, and radius ratio leads to an augmentation of the absolute value of the dimensionless velocity, temperature, velocity gradient, and temperature gradient of about 10-60%. Further, the augmentation of Bi₁ reduces the absolute value of the dimensionless temperature profile and dimensionless temperature gradient about three to four times; hence, the dimensionless heat transfer rate reduces. However, the growth of Bi₂ has a contrary impact. Besides, the increase of Pr and Ec leads to an increase in the dimensionless temperature profile and dimensionless temperature gradient; therefore, the dimensionless heat transfer rate increases.

The convection heat transfer on the walls of the pipes is considered, and the nonlinear coupled momentum and energy equations are solved using the least squared method and collocation methods, respectively.

The authors have determined whether the points fixed by all the full and the partial Atkin–Lehner involutions W_Q on X₀(N) for N ≤ 50 are Weierstrass points or not.

The design is by using Lawittes's and Schoeneberg's theorems.

Finding all Weierstrass points on X₀(N) fixed by some Atkin–Lehner involutions. Besides, the authors have listed them in a table.

The Weierstrass points have played an important role in algebra. For example, in algebraic number theory, they have been used by Schwartz and Hurwitz to determine the group structure of the automorphism groups of compact Riemann surfaces of genus g ≥ 2. Whereas in algebraic geometric coding theory, if one knows a Weierstrass nongap sequence of a Weierstrass point, then one is able to estimate parameters of codes in a concrete way. Finally, the set of Weierstrass points is useful in studying arithmetic and geometric properties of X₀(N).

The unique characteristic of Islamic bank leads in governance and disclosure. Using stakeholder, signaling, and market discipline theory, governance and adequate disclosure may increase bank soundness. This study aims to investigate the relationship of sharia disclosure and Sharia Supervisory Board in influencing Islamic bank soundness in the different regulatory framework of the country. Using purposive sampling, the research covered 84 Islamic banks in 16 countries during the period 2013–2015 with lag data of Islamic bank soundness. The result shows sharia disclosure influences on Islamic bank soundness for management efficiency, capital adequacy ratio, asset quality, and liquidity. The results also show that sharia disclosure mediates the indirect effect of SSB on Islamic bank soundness. The regulatory framework (sharia accounting standard and SSB regulation) shows moderating effect of regulation framework proved on the association of sharia disclosure with management efficiency, capital, and liquidity. The effect is indirectly depending on the regulatory framework for proxy management efficiency, capital, and liquidity. The implication of the research suggests that sharia disclosure could increase the market discipline mechanism of Islamic bank stream. The Islamic bank can increase the transparency using sharia disclosure as a branding for increasing public trust, even though in the deficient Islamic bank regulation countries.

We empirically investigate the hypothesis that the less transparent (more difficult to value) the target’s assets are the more likely it is that the acquiring firm can obtain higher short- and long-term returns. We analyze a sample of 1,538 friendly acquisitions partitioned in two separate dimensions: acquisitions of public versus private firms, and acquisitions of a firm’s assets versus acquisitions of a firm’s assets and its management. Using a sample of (nondiversifying) real estate transactions with a public REIT as the acquirer, we find that acquisitions of public firms have insignificant short-term abnormal returns. Acquisitions of private targets have positive and significant short-term abnormal returns. The acquirer’s abnormal returns are higher in both cases when the transactions involve acquisition of the target firm’s management. We find parallel results when analyzing the acquirer’s Q over the merger year and the three following years. Our conclusions are robust to the type of financing (cash, stock, or a combination) used in the acquisition.

This paper aims to investigate the macroeconomic effects of Qard-al-Hasan (QH) as a tool of monetary policy (MP) and its effectiveness in achieving full employment and price stability in the economy.

QH-based MP and its effects on major macroeconomic variables are examined on theoretical ground by using the standard aggregate output and aggregate expenditure model within the framework of Islamic economic principles.

QH-based MP positively influences real sectors of the economy and increases output, and the economy returns to full employment. QH provides the lowest possible borrowing costs across the economy and thus triggers rightward shift in aggregate supply curve and thus increases output and lowers price level. In addition, increase in output eliminates excess demand or shortages and thus maintains price stability. Furthermore, QH-based MP also increases exportable surplus and exports, decreases imports as well as increases inflow of funds and foreign currency reserves with the Central Bank and thus makes MP more effective.

QH-based MP is usually expansionary MP, and as such, it can be argued that there is a probability that QH-based MP may lead to higher inflation rate. However, in this study, it has been shown with real world data in Table II, that 23 countries in Group 1 have pursued zero or negative interest rate policy and their experiences mitigate such probability.

This is, perhaps, the first paper that presents a complete model of QH as a tool of MP with fully explained transmission mechanism. This is new contribution in the literature of Islamic finance where theoretical model on QH is systematically developed and applied as an effective tool of MP in attaining full employment and price stability. This model of QH-based MP can unfold a new horizon of uninterrupted economic growth, full employment and price stability by increasing output and employment, as well as by eliminating excess demand or shortages.

The purpose of this paper is to study the multi-phase flow behaviors in solid fluidization exploitation of natural gas hydrate (NGH) and its effect on the engineering safety.

In this paper, a multi-phase flow model considering the endothermic decomposition of hydrate is established and finite difference method is used to solve the mathematical model. The model is validated by reproducing the field test data of a well in Shenhu Sea area. Besides, optimization of design parameters is presented to ensure engineering safety during the solid fluidization exploitation of NGH in South China Sea.

To ensure the engineering safety during solid fluidization exploitation of marine NGH, taking the test well as an example, a drilling flow rate range of 40–50 L/s, drilling fluid density range of 1.2–1.23 g/cm3 and rate of penetration (ROP) range of 10–20 m/h should be recommended. Besides, pre-cooled drilling fluid is also helpful for inhibiting hydrate decomposition.

Systematic research on the effect of multiphase flow behaviors on the engineering safety is scare, especially for the solid fluidization exploitation of NGH in South China Sea. With the growing demand for energy, it is of great significance to ensure the engineering safety before the large-scale extraction of commercial gas from hydrate deposits. The result of this study can provide profound theoretical bases and valuable technical guidance for the commercial solid fluidization exploitation of NGH in South China Sea.

The purpose of this study is twofold. The first objective is to identify the factors that affect Gen Z tourists' M-payment behaviour. Next, this study investigates the inter-relationship between Gen Z tourist’s perception of M-payment benefits, adoption behaviour, usage risk and future usage intention.

The sample comprised Malaysian Gen Z individuals (n = 326) who had experience using M-payment methods while travelling outbound. Given the complex nature of the model and the goal to predict and explain relationships within Gen Z's M-payment usage, partial-least square-structural equation modelling was used to assess the study framework and test the proposed relationships.

This study reveals significant influences on Gen Z tourists' behavioural intentions towards M-payment usage. Perceived benefits, performance expectancy, social influence and perceived trust positively impact behavioural intentions, while effort expectancy exhibits no significant effect. Furthermore, perceived trust is strongly influenced by perceived security, which also positively influences behavioural intentions. A mediated relationship is evident as trust mediating the effect of perceived security on behavioural intentions.

This study’s findings contribute to understanding the intricate relationships influencing Gen Z's M-payment behaviour and underscore trust's pivotal role in mediating the security–behavioural intention relationship.

This study is among the first to consider Mental Accounting Theory and the Unified Theory of Acceptance and Use of Technology as crucial underpinning theories in comprehending the intricate relationships that influence Gen Z travellers' perceptions and behaviours concerning M-payment systems.

This study aims to compare the performance of the conventional and fractional order proportional-integral-derivative (PID and FOPID) controllers tuned with a particle swarm optimization (PSO) and genetic algorithm (GA) for quadrotor control.

In this study, the gains of the controllers were tuned using PSO and GA, which are included in the heuristic optimization methods. The tuning processes of the controller’s gains were formulated as optimization problems. While generating the objective functions (cost functions), four different decision criteria were considered separately: integrated summation error (ISE), integrated absolute error, integrated time absolute error and integrated time summation error (ITSE).

According to the simulation results and comparison tables that were created, FOPID controllers tuned with PSO performed better performances than PID controllers. In addition, the ITSE criterion returned better results in control of all axes except for altitude control when compared to the other cost functions. In the control of altitude with the PID controller, the ISE criterion showed better performance.

While a conventional PID controller has three parameters (Kp, Ki, Kd) that need to be tuned, FOPID controllers have two additional parameters (µ). The inclusion of these two extra parameters means more flexibility in the controller design but much more complexity for parameter tuning. This study reveals the potential and effectiveness of PSO and GA in tuning the controller despite the increased number of parameters and complexity.