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Several chaotic system-based encryption techniques have been presented in recent years to protect digital images using cryptography. The challenges of key distribution and administration make symmetric encryption difficult. The purpose of this paper is to address these concerns, the novel hybrid partial differential elliptical Rubik’s cube algorithm is developed in this study as an asymmetric image encryption approach. This novel algorithm generates a random weighted matrix, and uses the masking method on image pixels with Rubik’s cube principle. Security analysis has been conducted, it enhances and increases the reliability of the proposed algorithm against a variety of attacks including statistical and differential attacks.

In this light, a differential elliptical model is designed with two phases for image encryption and decryption. A modified image is achieved by rotating and mixing intensities of rows and columns with a masking matrix derived from the key generation technique using a unique approach based on the elliptic curve and Rubik’s cube principle.

To evaluate the security level, the proposed algorithm is tested with statistical and differential attacks on a different set of test images with peak signal-to-noise ratio, unified average changed intensity and number of pixel change rate performance metrics. These results proved that the proposed image encryption method is completely reliable and enhances image security during transmission.

The elliptic curve–based encryption is hard to break by hackers and adding a Rubik’s cube principle makes it even more complex and nearly impossible to decode. The proposed method provides reduced key size.

This research focuses on the controlling irreversibilities in a radiative, chemically reactive electromagnetohydrodynamics (EMHD) flow of a nanofluid toward a stagnation point. Key considerations include the presence of Ohmic dissipation, linear thermal radiation, second-order chemical reaction with the multiple slips. With these factors, this study aims to provide insights for practical applications where thermal management and energy efficiency are paramount.

Lie group transformation is used to revert the leading partial differential equations into nonlinear ODE form. Hence, the solutions are attained analytically through differential transformation method-Padé and numerically using the Runge–Kutta–Fehlberg method with shooting procedure, to ensure the precise and reliable determination of the solution. This dual approach highlights the robustness and versatility of the methods.

The system’s entropy generation is enhanced by incrementing the magnetic field parameter (M), while the electric field (E) and velocity slip parameters (ξ) control its growth. Mass transportation irreversibility and the Bejan number (Be) are significantly increased by the chemical reaction rate (C_r). In addition, there is a boost in the rate of heat transportation by 3.66% while 0.05⩽ξ⩽0.2; meanwhile for 0.2⩽ξ⩽1.1, the rate of mass transportation gets enhanced by 12.87%.

This paper presents a novel approach to analyzing the entropy optimization in a radiative, chemically reactive EMHD nanofluid flow near a stagnation point. Moreover, this research represents a significant advancement in the application of analytical techniques, complemented by numerical approaches to study boundary layer equations.

This paper aims to numerically examine the impact of gyrotactic microorganisms and radiation on heat transport features of magnetic nanoliquid within a closed cavity. Thermophoresis, chemical reaction and Brownian motion are also considered in flow geometry for the moment of nanoparticles.

Finite element method (FEM) was depleted to numerically approximate the temperature, momentum, concentration and microorganisms concentration of the nanoliquid. The present simulation was unsteady state, and the resulting transformed equations are simulated by FEM-based Mathematica algorithm.

It has been found that isotherm patterns get larger with increasing values of the magnetic field parameter. Additionally, numerical codes for rate of heat transport impedance inside the cavity with an increasing Brownian motion parameter values.

To the best of the authors’ knowledge, the research work carried out in this paper is new, and no part is copied from others’ works.

Historically, global events have always provided a setback to the existing mechanism of any business operation. The magnitude of such variation may be different from industry to industry but sustainable outlook afterwards any global crisis calls for a re-look into strategies. Similar experience persisted when sudden drop of brick-and-mortar stores during corona crisis came into picture. Post corona, the entire working style of supply chain companies revisited a virtual set-up. The delivery partners like Dunzo, Blinkit, Zypp, Delhivery, Ecomexpress have transformed the way logistics used to work before COVID-19. On the other hand, recent Russia–Ukraine war has posed further global challenges like that of food shortage, supply challenges, global inflation, recessionary trends worldwide. An investor earlier confident of exponential wealth creation in supply chain companies may have to rethink about resilient strategies while creating a portfolio with companies from supply chain industry. In the present study, a comparative analysis has been made by use of exponential Generalized AutoRegressive Conditional Heteroskedasticity (GARCH) model to explore the impact of both these crisis on returns from supply chain companies. The output of this chapter shall be beneficial for investors, asset management companies, investment brokers and other portfolio managers.

In this paper, free axisymmetric vibration analysis of a two-directional functionally graded porous thin annular plate resting on the Winkler foundation is presented utilizing the classical plate theory (CPT). The mechanical properties are considered to be varying in the radial-thickness plane.

Based on the CPT, the governing differential equation of motion is derived. The highest-order derivative of displacement is approximated by Haar wavelets and successive lower-order derivatives are obtained by integration. The integration coefficients are calculated using boundary conditions. The fundamental frequency for clamped-clamped, clamped-simply supported, simply supported-clamped and simply supported-simply supported boundary conditions is obtained.

The effects of the porosity coefficient, the coefficient of radial variation, the exponent of power law, the foundation parameter, the aspect ratio and boundary conditions are investigated on fundamental frequency. A convergence study is conducted to validate the present analysis. The accuracy and reliability of the Haar wavelets are shown by comparing frequencies with those available in the literature. Three-dimensional mode shapes in the fundamental mode for all four boundary conditions are presented.

Based on the Haar wavelet method, a free axisymmetric vibration model of a porous thin annular plate is solved in which 2-D variation of mechanical properties is considered.

The purpose of this study is to apply the Meshless Local Petrov–Galerkin (MLPG) method to solve the bending problems of linear viscoelastic plates, considering Reissner’s theory.

The weak formulation for the set of equations that govern Reissner’s plate theory is implemented in conjunction with the integral formulation applied to viscoelastic constitutive expressions. A meshless method based on the Moving Least Squares (MLS) approximation is considered in the numerical implementation. The final equation system is assembled by adopting simple and efficient schemes for numerical integration, considering a simplified formulation through centralization of the local interpolation domains and Gaussian quadrature at the same field point. The results obtained are compared with available solutions to demonstrate the efficiency of the proposed formulation.

The hereditary integral approach proved to be the most general way to analyze the viscoelastic problem, especially when applied together with the modified scheme for numerical integration. In addition, the variable changing technique is demonstrated to be an efficient formulation for solving shear-locking effects in thin plate problems.

The differential of the present study is related to the manner in which the properties of linear viscoelastic materials are considered in the formulation. Although most authors consider this point through the application of the correspondence principle, the present study works with a hereditary integral formulation. In addition, the variable changing technique is applied to solve the shear-locking effects, and an alternative approximation technique is considered to speed up the numerical integration process.

Food security emerges when all people always have physical and economic access to sufficient, safe, and nutritious food to meet their dietary needs and food preferences for an active and healthy life. The availability of food, access to food, and absorption of food are three key aspects of food security. Considering the above, the initial goal in this chapter is to measure annual growth rate and compound annual growth rate (CAGR) of production of food grains, nutri coarse cereals, total pulses, and nine oilseeds for the period 2011–2021 in India. To estimate per capita availability of Food Grains, Nutri Coarse Cereals, Total Pulses and Nine Oilseeds (in kg) represents the food security in India. The highest production is recorded in between 2011 and 2021 for food grains (315.72), followed by the production of nine oil seeds (36.7), total pulses (27.69), and nutri coarse cereals (26.42). In 2016, the annual growth rate for food grains and nine oilseeds was 9.37 and 23.88%, respectively. It is very evident that the availability per capita has grown from 2011 to 2021. The per capita availability of food grains increased from 206.17 kg in 2011 to 224.30 kg in 2021. The per capita availability of total pulses increased from 13.59 kg in 2011 to 19.67 kg in 2021. The per capita availability of nine oil seeds increased from 23.70 kg in 2011 to 26.78 kg in 2021 which indicates India has managed food security successfully in the last decade.

In this study, the authors sought to investigate how the implicit social ties of both project owners and potential backers are associated with crowdfunding project success.

Drawing on social ties theory and factors that affect crowdfunding success, in this research, the authors developed a model to study how project owners' and potential backers' implicit social ties are associated with crowdfunding projects' degrees of success. The proposed model was empirically tested with crowdfunding data collected from Kickstarter and social media data collected from Twitter. The authors performed the test using an ordinary least squares (OLS) regression model with fixed effects.

The authors found that project owners' implicit social ties (specifically, their social media activities, degree centrality and betweenness centrality) are significantly and positively associated with crowdfunding projects' degrees of success. Meanwhile, potential project backers' implicit social ties (their social media activities and degree centrality) are negatively associated with crowdfunding projects' degrees of success. The authors also found that project size moderates the effects of project owners' social media activities on projects' degrees of success.

This work contributes to the literature on crowdfunding by investigating how the implicit social ties of both potential backers and project owners on social media are associated with crowdfunding project success. This study extends the previous research on social ties' roles in explaining crowdfunding project success by including implicit social ties, while the literature explored only explicit social ties.

In the Indian economy, informal manufacturing enterprises play a pivotal role within the manufacturing sector, employing a vast workforce and significantly contributing to overall manufacturing output. While the number of these enterprises has risen over time, the exploration of CO₂ emissions from informal manufacturing enterprises is limited, especially in comparison to their formal counterparts. This chapter investigates the relationship between the growth status of informal manufacturing enterprises and their CO₂ emission intensity using the latest four rounds of quinquennial unit-level data from the National Sample Survey Organisation (NSSO). The analysis converts expenditure on electricity and fuel and lubricants into quantities, which are then multiplied by respective emission factors to determine enterprise-level CO₂ emissions. Findings indicate an increase in the percentage share of expanding and other status enterprises from 2000–2001 to 2015–2016, with other status enterprises being the most CO₂ emission-intensive, followed by contracting, expanding and stagnant enterprises. Notably, newer enterprises exhibit lower energy efficiency. Regression analysis further underscores a positive, significant link between growth status and CO₂ emission intensity, attributed to outdated machinery and equipment. Urban enterprises, often engaged in subcontracting activities with formal manufacturing industries, show higher CO₂ emission intensity. Challenges such as power outages significantly contribute to increased CO₂ emissions, highlighting the need for reliable electricity access and a reduction in fossil fuel dependence. This chapter underscores the importance of addressing these issues to align with India's Sustainable Development Goal (SDG) 13 objectives.

The affordable loss (AL) heuristic, as one crucial sub-dimension of effectuation, delineates the maximum level of investment entrepreneurs are ready to lose in a worst-case scenario. Conflicting conceptualizations remain regarding whether entrepreneurs’ psychological traits matter for AL. Based on the narcissistic admiration and narcissistic rivalry perspective, this study investigates the relationship between chief executive officer (CEO) narcissism and AL behaviors.

Using data collected from the CEOs and paired vice presidents at 122 small and medium enterprises (SMEs) in mainland China, the authors intend to further explore the association between psychological traits, especially CEO narcissism and AL behaviors under environment and resource constraints (e.g. perceived uncertainty and slack resources).

The findings show that CEO admiration-based narcissism is positively related to AL behaviors in the firm. Furthermore, when firms hold more slack resources, narcissistic admiration has a stronger positive association with AL; while when the environment becomes more uncertain, narcissistic admiration has a weaker positive association with AL. In contrast, CEO rivalry-based narcissism is negatively related to AL behaviors in the firm. When the environment becomes more uncertain, narcissistic rivalry has a stronger negative association with AL.

This article contributes to trait-based effectuation research and suggests that individual psychological traits affect AL behaviors at the firm level, though the patterns of the relationship vary with both the type of narcissism and contexts.