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Traditionally, the banking and financial sectors have pioneered adoption of new technologies and business models. One important digital banking model that has proven its efficacy in recent times, is Digital-Only Banking (DOB) where consumers interact with their banks through digital channels only. Having detailed knowledge of what actually happens at the consumer level during the adoption of new digital models and technologies is paramount to the success of these technological initiatives. The present study aims to investigate DOB adoption behavior and possible barriers using a quantitative approach at the consumer level. A conceptual model is developed by extending the Unified Theory of Acceptance and Use of Technology (UTAUT) model, incorporating Trust (TR), Perceived Risk (PR) constructs and cultural moderators of Individualism (IDV) and Uncertainty Avoidance (UA).

For this study, an online survey instrument was created and administered in Iran. The research sample was selected through the application of purposive sampling. Data from 788 respondents were analyzed. The proposed model was tested using Partial Least Square.?.s Structural Equation Modeling (PLS-SEM).

The results show that DOB adoption is positively influenced by Effort Expectancy (EE), Social Influence (SI), and Facilitating Conditions (FC), while PR negatively influences DOB adoption intention. Unexpectedly, the results indicate that TR has no significant impact on DOB usage intention. Additionally, this study demonstrates that with individuals having a low level of IDV, the relationship between PE and BI is stronger, and with individuals having a low level of UA, the impact of SI on BI is stronger. It also reveals that the impact of TR on BI is stronger in low individualistic cultures.

DOB providers should enhance support features of their services or provide facilities that make it simpler for users to accomplish online transactions. Here, in order to improve the UI/UX design of their apps, DOB product managers should carefully observe the technical guidelines of the operating systems of digital devices, such as the Human Interface Guidelines (HIG) for iOS and Material You for Android. Additionally, DOB providers should build partnerships with mega online retailers to provide hassle-free and easy to use payment solutions for consumers.

DOB, as a novel and business model, has been investigated in very few studies, especially regarding any which focus on its adoption. To fill this gap, this research investigates DOB adoption through a modified version of the UTAUT model. The findings of this study suggest that future research regarding DOB should consider sources of TR, types of non-adopters, and context. This study, as the first of its kind in DOB literature, also highlights the significant role played by cultural values in customer behavior regarding DOB adoption.

The purpose of this paper is to study the influence of magnetic field on natural convection inside the enclosures partially filled with conducting square solid obstacles. Also, the effect of thermal conductivity ratio between the solid and fluid materials is investigated for different number of solid blocks.

The dimensionless governing equations are transformed into sets of algebraic equations using finite volume method and momentum equations are solved by the SIMPLE algorithm with the hybrid scheme. The validation of the numerical code was conducted by comparing the results of average Nusselt number with previously published works.

The results indicate that both the magnetic field and solid blocks can significantly affect the flow and temperature fields. It is shown that for a given Rayleigh number, variation of Nusselt number might be increasing or decreasing with change in solid-to-fluid thermal conductivity ratio depending on magnetic field strength and number of solid blocks.

No work has been reported previously on the effect of magnetic field on natural convection flow in a cavity partially filled with square solid blocks. The numerical analysis of conductivity ratio between the solid and fluid materials under the effect of magnetic field have been carried out for the first time.

Spiral-wound heat exchangers (SWHEs) are widely used in different industries. In special applications, such as cryogenic (HEs), fluid properties may significantly depend on fluid temperature. This paper aims to present an analytical method for design and rating of SWHEs considering variable fluid properties with consistent shell geometry and single-phase fluid.

To consider variations of fluid properties, the HE is divided into identical segments, and the fluid properties are assumed to be constant in each segment. Validation of the analytical method is accomplished by using three-dimensional numerical simulation with shear stress transport k-ω model, and the numerical model is verified by using the experimental data. Moreover, the HE cost is selected as the main criterion in obtaining the proper design, and the most affordable geometry is selected as the proper design.

The accuracy of different heat transfer and pressure drop correlations is investigated by comparing the analytical and numerical results. The average errors in the calculation of effectiveness, shell-side pressure drop and tube-side pressure drop using the analytical method are 2.1%, 13.9% and 13.3%, respectively. Moreover, the effect of five main geometrical parameters on the SWHE cost is investigated. The results indicate that the effect of longitudinal pitch ratio on the SWHE cost can be neglected, whereas other geometrical parameters have a significant impact on the total cost of the SWHE.

This work contains a versatile and low-cost analytical method to design and rating the SWHEs considering the variable fluid property with consistent shell geometry. The previous studies have introduced complex methods and have not considered the consistency of shell geometry.

The purpose of this paper is to find a closed relation for the phase noise of LC oscillators.

The governing equation of oscillators is generally a stochastic nonlinear differential equation. In this paper, a closed relation for the phase noise of LC oscillators was obtained by approximating the I–V characteristic of the oscillator with third-degree polynomials and analyzing its differential equation.

This relation expresses phase noise directly in terms of circuit parameters, including the sizes of the transistors and the bias. Next, for evaluation, the phase noise of the cross-coupled oscillator without tail current was calculated with the proposed model. In this approach, the obtained equations are expressed independently of technology by combining the obtained phase noise relation and g_m/I_D method.

A technology-independent method using the g_m/I_D method and the closed relationship is provided to calculate phase noise.

This paper aims to find a closed-form expression for the frequency and amplitude of single-ended ring oscillators when transistors experience all regions.

In this paper, the analytical relationships presented for ring oscillator amplitude and frequency are approximately derived due to the nonlinear nature of this oscillator, taking into account the differential equation that governs the ring oscillator and its output waveform.

In the case where the transistors experience the cut-off region, the relationships presented so far have no connection between the frequency and the dimensions of the transistor, which is not valid in practice. The relationship is presented for the frequency, including the dimensions of the transistor. Also, a simple and approximately accurate relationship for the oscillator amplitude is provided in this case.

The validity of these relationships has been investigated by analyzing and simulating a single-ended oscillator in 0.18 µm technology.

Proper planning for the response phase of humanitarian relief can significantly prevent many financial and human losses. To this aim, a multi-objective optimization model is proposed in this paper that considers different types of injured people, different vehicles with determining capacities and multi-period logistic planning. This model can be updated based on new information about resources and newly identified injured people.

The main objective function of the proposed model in this paper is minimizing the unsatisfied prioritized injured people in the network. Besides, the total transportation activities of different types of vehicles are considered as another objective function. Therefore, these objectives are optimized hierarchically in the proposed model using the Lexicographic method. This method finds the best value for the first objective function. Then, it tries to optimize transportation activities as the second objective function while maintaining the optimality of the first objective function.

The performances of the proposed model were analyzed in different cases and its robust approach for different problems was shown within the framework of a case study. Besides, the sensitivity analysis of results shows the logical behavior of the proposed model against various factors.

The proposed methodology can be applied to find the best response plan for all crises.

In this paper, we have tried to use a multi-objective optimization model to guide and correct response programs to deal with the occurred crisis. This is important because it can help emergency managers to improve their plans.

The purpose of this paper is to design an applied mathematical model to maximize the profits of maintenance activities in manufacturing organizations, also providing an efficient solution method for that.

Reviewing published articles in the field of maintenance planning and then trying to model the problem to optimal decision making in this field.

Maintenance optimization can be done more appropriately by the accurate use of mathematical programming.

The existence of probabilistic parameters in this problem leads to hard stochastic programming.

Designing and organizing maintenance activities will increase productivity. This paper attempts to use mathematical models to optimize this matter.

This paper highlights the importance of using optimization methods for maintenance planning.

Hexagonal honeycombs with meso-metric cell size show excellent load bearing and energy absorption potential, which make them attractive in many applications. However, owing to their bend-dominated structure, honeycombs are susceptible to deformation localization. The purpose of this study is to provide insight about shear band propagation in struts of 3D-printed honeycombs and its relation to the achieved macroscopic mechanical behavior.

Hexagonal honeycombs and unit cell models are 3D-printed by fused deposition modeling (FDM). The samples are exposed to compression loading and digital image correlation technique and finite element analyses are incorporated.

It is found that the strain contours, which are obtained by finite element, are in agreement with experimental measurements made by DIC. In addition, three stages of shear band propagation in struts of 3D-printed honeycombs are illustrated. Then the correlation between shear band propagation stages and the achieved macroscopic mechanical responses is discussed in detail.

For the first time, a hierarchical activation of different modes of shear band propagation in struts of a 3D-printed honeycomb is reported. This information can be of use for designing a new generation of honeycombs with tailor-made localization and energy absorption potential.

This paper aims to study the thermal and thermo-hydraulic performances of ferro-nanofluid flow in a three-dimensional trapezoidal microchannel heat sink (TMCHS) under uniform heat flux and magnetic fields.

To investigate the effect of direction of Lorentz force the magnetic field has been applied: transversely in the x direction (Case I);transversely in the y direction (Case II); and parallel in the z direction (Case III). The three-dimensional governing equations with the associated boundary conditions for ferro-nanofluid flow and heat transfer have been solved by using an element-based finite volume method. The coupled algorithm has been used to solve the velocity and pressure fields. The convergence is reached when the accuracy of solutions attains 10–6 for the continuity and momentum equations and 10–9 for the energy equation.

According to thermal indicators the Case III has the best performance, but according to performance evaluation criterion (PEC) the Case II is the best. The simulation results show by increasing the Hartmann number from 0 to 12, there is an increase for PEC between 845.01% and 2997.39%, for thermal resistance between 155.91% and 262.35% and ratio of the maximum electronic chip temperature difference to heat flux between 155.16% and 289.59%. Also, the best thermo-hydraulic performance occurs at Hartmann number of 12, pressure drop of 10 kPa and volume fraction of 2%.

The embedded electronic chip on the base plate generates heat flux of 60 kW/m2. Simulations have been performed for ferro-nanofluid with volume fractions of 1%, 2% and 3%, pressure drops of 10, 20 and 30 kPa and Hartmann numbers of 0, 3, 6, 9 and 12.

The authors obtained interesting results, which can be used as a design tool for magnetohydrodynamics micro pumps, microelectronic devices, micro heat exchanger and micro scale cooling systems.

Review of the literature indicated that there has been no study on the effects of magnetic field on thermal and thermo-hydraulic performances of ferro-nanofluid flow in a TMCHS, so far. In this three dimensional study, flow of ferro-nanofluid through a trapezoidal heat sink with five trapezoidal microchannels has been considered. In all of previous studies, in which the effect of magnetic field has been investigated, the magnetic field has been applied only in one direction. So as another innovation of the present research, the effect of applying magnetic field direction (transverse and parallel) on thermo-hydraulic behavior of TMCHS is investigated.

The purpose of this paper is to investigate the simultaneous effects of ionization and dispersion of soil on the impulse behavior of grounding electrodes under first and subsequent stroke currents.

A recently introduced technique called improved multi-conductor transmission line (MTL) is simplified for grounding electrodes buried in both-affected soils.

The simulation results show that including the two effects simultaneously in highly resistive soils under high-valued subsequent stroke current is recommended. Otherwise, simultaneous effects can be disregard.

To the best of the authors’ knowledge, there is no research on sensitivity analyses for the simultaneous inclusion of the two effects on the effective length and the induced voltage on the soil surface. To this end, the simplified MTL is applied to the grounding electrodes. The simulation results show that the computational efficiency in comparison with previous methods is, first, considerably increased. Second, the simultaneous effects result in decreasing the soil surface voltage with respect to situations where either ionization or dispersion is taken into account (single-affected soils). In other words, the performance of grounding systems is improved. Third, the effective length in both-affected soil is has a middle value with respect to the single-affected soil. Such findings practically and financially are of importance.