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The Indonesian Islamic banking industry is very promising, but there has been no analysis of the optimal and decreasing growth rate of the industry. Information regarding these is essential for policy makers, Islamic bankers and all related parties to guide the future development of the industry and sets up proper plans and strategies. The paper aims to explore the optimal and decreasing growth rates of the industry and in so doing contribute to the current literature on the Indonesian Islamic banking industry.

The paper first reports on the performance of the Indonesian Islamic banking industry, before explaining conditions where the Islamic banking industry is believed to be still immature. Third, in order to identify the optimal and decreasing growth rates, the paper estimates the future performance of the industry by using ARIMA models to identify periods where the growth rate is at optimal and decreasing points. Then, on the basis of a number of assumptions and statistical simulations, the analysis broadens to become qualitative in nature by determining the optimal numbers of Islamic banks to be established in the future.

The paper generates some important findings. First, the optimum growth rate of the market share (0.12 percent) is predicted to occur in December 2012; the market share in that month is estimated to be 5.75 percent. Second, although the market share keeps growing, the paper finds the rate of increase to be slow, and in October 2018, it becomes negative, at 0.004 percent. The estimated market share in that time is 11.63 percent. Finally, the optimal number of Islamic banks in December 2012 is shown to be 23 and in October 2018, 24.

Qualitative information on the months of the optimal and decreasing growth rates and quantitative information on the optimal number of Islamic banks to be established are significant information for policy makers, Islamic bankers and other related parties. The information is likely to be important in relation to their efforts to develop the Islamic banking industry, to anticipate decreasing growth in the industry and to establish new Islamic banks. More generally, the paper helps the related parties to direct and guide the future development of the industry.

To the best of the authors' knowledge, this is the first paper that attempts to establish optimal and decreasing growth rates in the Indonesian Islamic banking industry, or the optimal numbers of Islamic banks to be established in the future.

The hydrodynamic characteristic of a buoyancy‐driven convection loop containing an electrically‐conducting fluid in a transverse magnetic field is numerically investigated using a two‐dimensional spectral element numerical model. One side of the loop is heated isothermally, the other side is cooled isothermally and the top and bottom sections are insulated. The study covers ranges of Grashof number, Gr, from 10³ to 10⁵, the Hartmann number, Ha, from 0 to 20, loop height to thickness ratio, L/d, from 10 to 20 and at Prandtl numbers of Pr = 0.02 and Pr = 1. Results are presented for the velocity, temperature profiles and heat transfer in terms of Hartmann number. At high Hartmann numbers the velocity gradient in the core of the flow decreases outside the Hartmann layer in the vicinity of the walls normal to the magnetic field. Comparison is made with the analytical solution of Ghaddar (1997), based on a parallel flow approximation and its range of validity is delineated. The numerical analysis compares well with the closed form analytical solution of the magnetohydrodynamic generator for the flow velocity and the induced current. This study reveals the existence of an optimal Hartmann number at which the induced electric current is maximised for all ranges of Prandtl numbers. The optimal Hartmann number found numerically for Pr = 0.02 is similar to the one predicted by the analytical 1‐D model.

The restructuring of shipping and shipbuilding companies in the midst of rapidly shrinking global shipping demand has become a prominent issue in Korea. In shipping finance, loan syndication featuring many creditors surges as the preferred option. However, increasing the numbers of creditors in the syndicate results in two opposite effects. First is the beneficial effect from their enhanced monitoring power. On the other hand, there is the adverse effect resulting from increased difficulty in coordination when syndicate members increase, particularly in bankruptcy. Our aim of this paper is to analyze the role of finance in the shipping and shipbuilder markets, and determine the theoretical optimal number of creditors for the shipping finance syndicate based on Bolton and Scharfstein (1996). The two issues above result from moral hazard and non-verifiability: coordination among many creditors for collection of bonds in case of default, and the enhancement of monitoring private benefit exploitation by the ship-owner during default. Considering the two conflicting forces result from an increase in creditor membership, we draw conclusions on determining the optimal number of creditors by considering trade-offs between these two factors: More creditors are preferred when the monitoring effect dominates. Otherwise, less creditors are preferred.

The purpose of this study is to analyze a new idea for external flow over a cylinder to increase the heat transfer and reduce pressure drop. Using wedge-shaped porous media in the front and wake regions of the cylinder can improve its hydrodynamic, and the rotating flow in the wake region can enhance the heat transfer with increased porous–liquid contact. Permeability plays a vital role, as a high-permeable medium improves heat transfer, whereas a low-permeable region improves the hydrodynamic.

Therefore, in the current research, external forced convection of nanofluid laminar flow over a bundle of cylinders is simulated using a two-phase mixture model. Four cases with different porous blocks around the cylinder are assessed: rectangular porous; wedge shape in trailing edge (TEP); wedge shape in leading and trailing edges (LTEP); and no porous block case. Also, three different lengths of wedge-shaped regions are considered for TEP and LTEP cases.

Results are presented in terms of Nusselt (Nu), Euler (Eu) and the performance evaluation criterion (PEC) numbers for various Reynolds (Re) and Darcy (Da) numbers.

It was found that in most situations, LTEP case provides the highest Nu and PEC values. Also, optimal Re and porous medium length exist to maximize PEC, depending on the values of Da and nanofluid volume fraction.

Embracing a large set of innovation objectives and collaborating with diverse partners have been promoted as a means to improve innovation performance. However, empirical evidence on the relationships between breadth of objectives, breadth of cooperation and innovation performance is limited, particularly in the context of emerging economies. A larger number of objectives and cooperation partners inevitably increases the complexity in organizational alignment, and cooperation eventually leads to diminishing returns. This study adds to the debate on the costs and benefits of cooperation for innovation. Understanding the optimal levels of the breadth of objectives and cooperation supports managerial decision-making and productivity in the practice of cooperation for innovation.

Operationalizing breadth of innovation objectives and cooperation via the Turkish Community Innovation Survey data, self-reports reflecting 5,863 firm-level responses between 2006 and 2008 are analysed using tobit and probit models. The maximum likelihood estimator is used to find the optimal levels for breadth of objectives and cooperation.

Firms with greater breadth of innovation objectives experience higher innovation performance; those with greater breadth of cooperation also experience higher innovation performance, but our results indicate the existence of optimal levels of breadth for both innovation objectives and cooperation.

The authors extend the logic that there is no safety in numbers in cooperation for innovation. If the aim is to enhance innovation performance, managers and policymakers need to pay attention to the number of innovation objectives and the amount of cooperation pursued by firms. However, innovation success may be closely associated with a firm's dynamic capabilities and ability to mobilize its resources. Drawing on organizational learning theories, future research could explore why a lower than maximum level of cooperation may be more conducive to reaching levels of enhanced innovation performance and whether this level is influenced by cognitive processes.

The authors draw attention to the ideal number of innovation objectives and number of cooperating partners required to enhance innovation performance, thus contributing to the debate on the complex relationships between innovation, performance and cooperation in the unique setting of a large developing economy.

Computerized layout (or “topology”) optimization was pioneered almost four decades back. However, despite dramatic increases in available computer power and the application of increasingly efficient optimization algorithms, even now only relatively modest sized problems can be tackled using the traditional “ground structure” approach. This is because of the need, in general, for the latter to contain every conceivable member connecting together the nodes in a problem. A simple, but effective solution method capable of tackling problems with large numbers of potential members (e.g. >100,000,000) is presented. Though the method draws on the linear programming technique of “column generation”, since layout optimization specific heuristics are employed it is presented as an iterative “member adding” method. The method requires a ground structure with minimal connectivity to be used in the first iteration; members are then added as required in subsequent iterations until the (provably) optimal solution is found.

Order picking is one of the most costly logistics processes in warehouses. As a result, the optimization of order picking processes has received an increased attention in recent years. One potential source for improving order picking is the reduction of picker blocking. The purpose of this paper is to investigate picker blocking under different storage assignment and order picker-route combinations and evaluate its effects on the performance of manual order picking processes.

This study develops an agent-based simulation model (ABS) for order picking in a rectangular warehouse. By employing an ABS, we are able to study the behaviour of individual order pickers and their interactions with the environment.

The simulation model determines shortest mean throughput times when the same routing policy is assigned to all order pickers. In addition, it evaluates the efficiency of alternative routing policies–storage assignment combinations.

The paper implies that ABS is well-suited for further investigations in the field of picker blocking, for example, with respect to the individual behaviour of agents.

Based on the results of this paper, warehouse managers can choose an appropriate routing policy that best matches their storage assignment policy and the number of order pickers employed.

This paper is the first to comprehensively study the effects of different combinations of order picker routing and storage assignment policies on the occurrence of picker blocking.

The objective of this research study is to formulate and develop a novel optimization model that enables planners of modular construction to minimize the total transportation and storage costs of prefabricated modules in modular construction projects.

The model is developed by identifying relevant decision variables, formulating an objective function capable of minimizing the total transportation and storage costs and modelling relevant constraints. The model is implemented by providing all relevant planner-specified data and performing the model optimization computations using mixed-integer programming to generate the optimal solution.

A case study of hybrid modular construction of a healthcare facility is used to evaluate the model performance and demonstrate its capabilities in minimizing the total transportation and onsite storage costs of building prefabricated modules.

The model can be most effective in optimizing transportation for prefabricated modules with rectangular shapes and might be less effective for modules with irregular shapes. Further research is needed to consider the shape of onsite storage area and its module arrangement.

The developed model supports construction planners in improving the cost effectiveness of modular construction projects by optimizing the transportation of prefabricated modules from factories to construction sites.

The original contributions of this research is selecting an optimal module truck assignment from a feasible set of trucks, identifying an optimal delivery day of each module as well as its location and orientation on the assigned truck and complying with relevant constraints including the non-overlap of modules on each truck, shipment weight distribution and aerodynamic drag reduction.

This paper aims to numerically investigate the magnetohydrodynamic (MHD) convection heat transfer of nanofluid inside a differentially heated enclosure with various fin morphologies.

The fluid flow within the cavity was governed by N-S equations while it within porous medium was solved by the non-Darcy model, called the Darcy–Forchheimer model based on representative element-averaging method. Empirical correlations from experimental data are used to evaluate the effective thermal conductivity and dynamic viscosity. Relevant governing parameters, including thermal Rayleigh number (10⁵-10⁷), Hartmann number (0-50), Darcy number (10⁻⁶-10⁻¹), thermal conductivity ratio of porous matrix (1-10³), nanoparticles volume fraction (0-0.04) and topology designs of porous fins, are sensitively varied to identify their effects and roles on the fluid flow and heat transfer. Particularly, heatlines are used to investigate the mechanism of heat transport.

Numerical results demonstrate that the predictions of average Nusselt number are augmented by using more porous fins with high permeability, and this effect becomes opposite in tiny Darcy numbers. Particularly, for high Darcy and Rayleigh numbers, the shortest fins could achieve the best performance of heat transfer. In addition, the prediction of average Nusselt number reduces with an increase in Hartmann numbers. An optimal nanoparticles concentration also exists to maximize heat transfer enhancement. Finally, numerical correlations for the average Nusselt number were proposed as functions of these governing parameters.

Present work could benefit the thermal design of electronic cooling and thermal carriers in nanofluid engineering.

Present work could benefit the thermal design of electronic cooling and thermal carriers in nanofluid engineering. In addition, optimum thermal removals could enhance the lifetime of electronics, therefore reducing the cost of energy and materials.

To the best knowledge of authors, there are not any studies considering the synergetic effects of porous fins on MHD convection of nanofluids. Present work could benefit the thermal design of electronic cooling and thermal carriers in nanofluid engineering.

The purpose of this paper is to present a novel and applied method for optimum designing of plate-finned heat exchanger network. Considering the total annual cost as the objective function, a network of plate-finned heat exchanger is designed and optimized.

Accurate evaluation of plate-finned heat exchanger networks depends on different fin types with 10 different geometrical parameters of heat exchangers. In this study, fin numbers are considered as the main decision variables and geometrical parameters of fins are considered as the secondary decision variables. The algorithm applies heat transfer and pressure drop coefficients correction method and differential evolution (DE) algorithm to obtain the optimum results. In this paper, optimization and minimization of the total annual cost of heat exchanger network is considered as the objective function.

In this study, a novel and applied method for optimum designing of plate-finned heat exchanger network is presented. The comprehensive algorithm is applied into a case study and the results are obtained for both counter-flow and cross-flow plate-finned heat exchangers. The total annual cost and total area of the network with counter-flow heat exchangers were 12.5% and 23.27%, respectively, smaller than the corresponding values of the network with cross-flow heat exchanger.

In this paper, a reliable method is used to design, optimize parameters and the economic optimization of heat exchanger network. Taking into account the importance of plate-finned heat exchangers in industrial applications and the complexity in their geometry, the DE methodology is adopted to obtain an optimal geometric configuration. The total annual cost is chosen as the objective function. Applying this technique to a case study illustrates its capability to accurate design plate-finned heat exchangers to improve the objective function of the heat exchanger network from the economic viewpoint with the design of details.