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This study aims to examine the characteristics of cross-border central bank digital currencies (CBDCs) while pinpointing research trends and adoption variables at both individual and macroeconomic levels. Additionally, it delves into the impact of terminology within CBDC-related scholarly literature themes.

The authors perform a bibliometric study using the metadata of academic papers about CBDC from ScienceDirect, Scopus and Web of Science (WoS), three reputable research databases. Word maps are produced using VOSviewer, an open-source bibliometric analytics program, to find pertinent and predominate words and phrases based on their frequency, placement, connection and co-occurrence. Additionally, the authors use the R programing language to assess the Jaccard similarity between bibliometric metadata and the financial terms in the Loughran-McDonald Master Dictionary (LMMD).

The study pinpoints the factors that affect CBDC adoption at the micro and macroeconomic levels. Insights into prospective future study themes are provided by the analysis of the metadata corpus, which shows significant and predominate words/phrases and themes in CBDC literature. Notably, the relatively low Jaccard similarity scores in the scholarly literature on CBDC-related topics across all three bibliometric databases suggest a restricted concentration on financial issues. This shows that CBDC research is still in its early stages and that there are still many undiscovered financial aspects.

The identification of literature’s themes using dominant and pertinent words based on bibliometric metadata, considering factors such as frequency and co-occurrence, enriches the evolving field of meta-analysis. Additionally, the use of the Jaccard index to assess the coverage of financial terms within bibliometric metadata represents a unique approach, shedding light on the distinctive aspects of CBDC research.

The purpose of this paper is to discuss the flow and heat transference of unsteady nanofluid thin film flow due to linear stretching velocity over a horizontally placed stretching sheet in corporation of aligned magnetic field and non-uniform heat source/sink.

Leading equations of the course have been normalized via similarity approach and unraveled the resulting non-linear equations numerically by consuming RK-4 shooting practice to execute flow analysis.

A close agreement of two sets (for two different base fluids – polyvinyl alcohol and water) of result is perceived. The authors find that inclined magnetic field and nanoparticles concentration curbed velocity distribution which, in turn, causes enrichment of system of temperature distribution.

The paper acquires realistic numerical explanations in form of rapidly convergent series. The influence of emergent flow parameters on specific flow are made appropriately via graphs and charts. An unbiased result scrutiny of the existing section with formerly conveyed result is provided.

The purpose of this paper is to focus on the influence of multiple slips on MHD Williamson nanofluid flow embedded in porous medium towards a linearly stretching sheet that has been investigated numerically. The whole analysis has been carried out considering the presence of nth-order chemical reaction between base fluid and nanoparticles.

A similarity transformation technique has been adopted to convert non-linear governing partial differential equations into ordinary ones and then they are solved by using both the RK-4 method and Laplace transform homotopy perturbation method. The consequences of multiple slip parameters on dimensionless velocity, temperature and concentration and heat and mass transfer rates have been demonstrated using tabular and graphical outline.

The investigation explores that the Nusselt number reduces for escalating behaviour of velocity slip and thermal slip parameter. Fluid’s temperature rises in the presence of generative reaction parameter.

A fine conformity of the current results has been achieved after comparing with previous literature studies. Considering destructive chemical reaction, reduced Nusselt number is found to decrease, but reverse consequence has been noticed in the case of generative chemical reaction. Mass transport diminishes when the order of chemical reaction amplifies for both destructive and generative reactions.

Hybrid nanofluids are of significant engrossment for their considerable heat transport rate. The steady flow of an incompressible viscous electrically conducted hybrid nanofluid is considered over a rotating disk under a magnetic field. Titanium oxide (TiO₂) and ferrous (CoFe₂O₄) nanoparticles are used with their physical properties and water is considered as host liquid. The purpose of this paper is to analyze how hydrothermal integrity varies for hybrid nanosuspension over a spinning disk in the presence of magnetic orientation.

Governing equations with boundary conditions are transformed by similarity transformations and then solved numerically with RK-4 method. A comparison of linear and nonlinear thermal radiation for the above-mentioned parameters is taken and the efficiency of nonlinear radiation is established, the same over nanofluid and hybrid nanofluid is also discussed. Heat lines are observed and discussed for various parameters like magnetic field, concentration, suction and injection parameter, radiation effect and Prandtl number.

Suction and increasing nanoparticle concentration foster the radial and cross-radial velocities, whereas magnetization and injection confirm the reverse trend. The rate of increment of radial friction is quite higher for the usual nanosuspension. The calculated data demonstrate that the rate for hybrid nanofluid is 8.97 percent, whereas for nanofluid it is 15.06 percent. Double-particle suspension amplifies the thermal efficiency than that of a single particle. Magnetic and radiation parameters aid the heat transfer, but nanoparticle concentration and suction explore the opposite syndrome. The magnetic parameter increases the heat transport at 36.58 and 42.71 percent for nonlinear radiation and hybrid nanosuspension, respectively.

Nonlinear radiation gives a higher heat transport rate and for the radiation parameter it is almost double. This result is very significant for comparison between linear and nonlinear radiation. Heat lines may be observed by taking different nanoparticle materials to get some diverse result. Hydrothermal study of such hybrid liquid is noteworthy because outcomes of this study will aid nanoscience and nanotechnology in an efficient way.

The focus of the paper is only on the contributions toward the use of entropy generation of non-Newtonian Casson fluid over an exponential stretching sheet. The purpose of this paper is to investigate the entropy generation and homogeneous–heterogeneous reaction. Velocity and thermal slips are considered instead of no-slip conditions at the boundary.

Basic equations in form of partial differential equations are converted into a system of ordinary differential equations and then solved using the spectral quasi-linearization method (SQLM).

The validity of the model is established using error analysis. Variation of the velocity, temperature, concentration profiles and entropy generation against some of the governing parameters are presented graphically. It is to be noted that the increase in entropy generation due to increase in heterogeneous reaction parameter is due to the increase in heat transfer irreversibility. It is further noted that the Bejan number decreases with Brinkman number because increase in Brinkman number reduces the total entropy generation.

This paper acquires realistic numerical explanations for rapidly convergent temperature and concentration profiles using the SQLM. Convergence of the numerical solutions was monitored using the residual error of the PDEs. The resulting equations are then integrated using the SQLM. The influence of emergent flow, heat and mass transfer parameters effects are shown graphically.

A porous cavity flow field generates entropy owing to energy and momentum exchange within the fluid and at solid barriers. The heat transport and viscosity effects on fluid and solid walls irreversibly generate entropy. This numerical study aims to investigate convective heat transfer together with entropy generation in a partially heated wavy porous cavity filled with a hybrid nanofluid.

The governing equations are nondimensionalized and the domain is transformed into a unit square. A second-order finite difference method is used to have numerical solutions to nondimensional unknowns such as stream function and temperature. This numerical computation is conducted to explore a wide range of regulating parameters, e.g. hybrid nano-particle volume fraction (σ = 0.1%, 0.33%, 0.75%, 1%, 2%), Rayleigh–Darcy number (Ra = 10, 10², 10³), dimensionless length of the heat source (ϵ = 0.25, 0.50,1.0) and amplitude of the wave (a = 0.05, 0.10, 0.15) for a number of undulations (N = 1, 3) per unit length.

A thorough analysis is conducted to analyze the effect of multiple factors such as thermal convective forces, heat source, surface corrugation factors, nanofluid volume fraction and other parameters on entropy generation. The flow and temperature fields are studied through streamlines and isotherms. The average Bejan number suggested that entropy generation is entirely dominated by irreversibility due to heat transport at Ra = 10, and the irreversibility due to the viscosity effect is severe at Ra = 10³, but the increment in s augments irreversibility due to the viscosity effect over the heat transport at Ra = 10².

To the best of the authors’ knowledge, this numerical study, for the first time, analyzes the influence of surface corrugation on the entropy generation related to the cooling of a partial heat source by the convection of a hybrid nanofluid.

The investigation has appraised the problem of an incompressible laminar steady magnetohydrodynamic (MHD) nanofluid stream over three distinct slendering thin isothermal needles of paraboloid, cylindrical and cone shapes. Water as a base liquid is assumed in this flow model. The influences of the Hall current and variable sorts of magnetic forces have enriched our investigation. Energy and concentration expressions consist of thermophoresis and Brownian migration phenomena. The analysis of thermal and mass slips of the presumed model has also been performed.

A relevant transformation is implemented for the alteration of the leading partial differential equations (PDEs) to the equations with nonlinear ordinary form. Due to the strong nonlinearity of the foremost equations, the problem is solved numerically by embedding the well-known RK-4 shooting practice. The software MAPLE 2017 has been exploited in reckoning the entire computation. To enunciate the investigated upshots, some graphical diagrams have been regarded here. According to technological interest, we measured the engineering quantities like the Sherwood number, the coefficient of drag friction and the Nusselt number in tabular customs.

The obtained consequences support that Hall current intensifies fluid movement when the needle is in a cone shape, while the superior velocity is noticed for cylindrical-shaped needles. The transference of heat responds inversely along with the growths of thermal and mass slip factors.

No work has been performed on the flow model of radiated nanofluid over a variable-shaped thin needle under Hall current, the variable magnetic field and different slip factors.

This paper aims to present object or feature segmentation from an ordered 3D point cloud range data obtained from a laser scanner for the purpose of robot navigation.

Rotating multi-beam laser scanners provide ordered 3D range data. Differences between consecutive ranges in radial direction are used to compute a novel measure of terrain unevenness at each data point. Computed over a complete rotation, an unevenness field is formed surrounding the scanner. A part of this field staying below a threshold is recognized as ground and removed. Remaining non-ground points are segmented into objects by region growing with points whose unevenness lies within pre-specified limiting values.

The proposed unevenness attribute is simple and efficient for segmenting distinct objects or features. The fineness of surface features can be regulated by adjusting the threshold value of difference in unevenness between neighbouring points that triggers an onset of new segments.

The angles between neighbouring laser range data are assumed to be known.

Segmented objects or features can be used for scan registration, object tracking and robot navigation.

The method may find use in autonomous robots and driverless cars.

Differences between consecutive range data are used imaginatively to derive a novel measure of terrain unevenness, which in turn, is used for efficient segmentation of objects and features.

The purpose of this paper is to detect traversable regions surrounding a mobile robot by computing terrain unevenness using the range data obtained from a single 3D scan.

The geometry of acquiring range data from a 3D scan is exploited to probe the terrain and extract traversable regions. Nature of terrain under each scan point is quantified in terms of an unevenness value, which is computed from the difference in range of scan point with respect to its neighbours. Both radial and transverse unevenness values are computed and compared with threshold values at every point to determine if the point belongs to a traversable region or an obstacle. A region growing algorithm spreads like a wavefront to join all traversable points into a traversable region.

This simple method clearly distinguishes ground and obstacle points. The method works well even in presence of terrain slopes or when the robot experiences pitch and roll.

The method applies on single 3D scans and not on aggregated point cloud in general.

The method has been tested on a mobile robot in outdoor environment in our research centre.

This method, along with advanced navigation schemes, can reduce human intervention in many mobile robot applications including unmanned ground vehicles.

Range difference between scan points has been used earlier for obstacle detection, but no methodology has been developed around this concept. The authors propose a concrete method based on computation of radial and transverse unevenness at every point and detecting obstacle edges using range-dependent threshold values.

This study aims to investigate and compare the influence of various fiber types (polypropylene, steel and glass) on the workability, mechanical properties, ductility, impact resistance, durability and microscopic properties of geopolymer concrete (GPC) with conventional concrete (CC).

The CC and GPC of M40 grade were incorporated with an optimum 1% of fibers and superplasticizers were added in a ratio of 2% by weight of the geopolymer binder. The slump cone and compaction factor tests were performed to analyze the workability. To evaluate the mechanical performance of GPC, the compressive strength (CS), split tensile strength (STS), flexural strength (FS) and modulus of elasticity (MOE) tests were performed. A falling weight impact test was performed to determine the impact energy (IE) absorbed, the number of blows for initial cracking, the number of blows for complete failure and the ductility aspect.

Fibers and superplasticizers significantly improve GPC properties. The study found that fibers reduce the brittleness of concrete, improving the impact and mechanical strength compared to similar-grade CC. The steel fibers-reinforced GPC has a 15.42% higher CS than CC after three days, showing a faster CS gain. After 28 days, GPC and CC have MOE in the range of 23.9–25.5 GPa and 28.8–30.9 GPa, respectively. The ultimate IE of the GPC with fibers was found to be 5.43% to 21.17% higher than GPC without fibers.

The findings of the study can be used to explore different combinations of raw materials and mix designs to optimize the performance of GPC.