Hasil untuk "Plasma engineering. Applied plasma dynamics"

Dehua Zhang, Xian Jiang, Tao Tao et al.

The self-generated magnetic field coupled with the growth of multimode ablative Rayleigh–Taylor instability (ARTI) is investigated by numerical simulations with Nernst effects, resistivity and magnetized heat conduction taken into account. It is found that intense magnetic fields about 1 kT can be generated in multimode ARTI via the Biermann-battery source and the Nernst amplification. The enhancement of the self-similar growing coefficient α _b caused by self-generated magnetic fields is attributed to the reinforcement of the vorticity inside the bubbles. It is also found that α _b is enhanced more significantly in cases where the perturbation spectra contain more short-wavelength components. The formula for the dependence of α _b on the initial perturbation amplitude proposed in Zhang et al (2018 Phys. Rev. Lett. 121 185002) remains applicable, but requires a modified coefficient to account for the attenuation of ablative stabilization due to self-generated magnetic fields.

Isaac Nsor, Bennetta Koomson, Patrick Boakye

A Jatropha curcas-based bio-lubricant was developed and evaluated for automotive applications through acid esterification, base-catalyzed transesterification, in-situ peracetic acid epoxidation, and multi-additive blending. The molecular transformations were confirmed by GC–MS and FTIR, and physical properties were assessed using ASTM/ISO methods. Performance was further evaluated through a 12,000 km in-service motorcycle engine test and XRF wear analysis. Transesterification decreased kinematic viscosity at 40 °C from 36.6 to 16.7 cSt, and subsequent epoxidation and additive incorporation increased the viscosity to 47.2 cSt (40 °C) and 15.2 cSt (100 °C), meeting ISO VG-46 requirements. The resultant composition (JOA) showed density (888 kg m⁻³), viscosity index (227), pour point (−20 °C), flash point (230 °C), free fatty acid content (0.1%), and acid value < 0.5 mg KOH g⁻¹. The predominant components of JOA were determined by GC–MS, and ester and epoxide functionalities were confirmed by FTIR. During operation, the viscosity index decreased to 192.9, while maintaining acceptable viscosity retention and thermal stability. XRF analysis indicated controlled wear, with metal concentrations remaining within reported OEM guideline ranges. These results demonstrate the feasibility of using Jatropha curcas oil as a sustainable base stock for automotive lubricants.

S Navaneethan, A Arun

Wireless Sensor Networks (WSNs) require efficient routing mechanisms to ensure reliable data delivery while minimizing energy consumption and communication delay in resource-constrained environments. Conventional methods, including contention-based transmission schemes, often suffer from packet collisions, retransmissions, and increased latency as network density mounts. To combat these challenges, this paper proposes a Backward Token-Based Routing Framework (BTBRF) that allows a sink-initiated reverse-direction token propagation for hierarchical routing tree construction and controlled transmission scheduling in multi-hop WSN structures. In the proposed approach, backward tokens are generated at the sink node and establish parent–child relationships using hop count, path cost, and residual energy metrics. This ensures loop-free topology formation and regulated channel access. Hence, only authorized nodes participate in communication at a given time. The performance of the proposed framework was evaluated using the QualNet network simulator by varying node densities from 20 to 100 nodes. Simulation results demonstrate that the proposed method improves packet delivery ratio and throughput while reducing end-to-end delay and overall energy consumption compared with conventional single-token communication methods.

Nilesh H. Thube, R. Lodhi

The Newell-Whitehead-Segel (NWS) equation plays a significant role in nonlinear systems, including mathematical biology, plasma physics, solid-state physics, optics, quantum mechanics, cosmology, fluid dynamics, and many others. In this work, we proposed the quintic B-spline collocation method to find the numerical solution of the nonlinear NWS-type equation. Crank-Nicolson finite difference method (FDM) is used to discretize the equation in time space, and quasi-linearization is employed to linearize the nonlinear term. The stability analysis has been discussed using the Von Neumann Method, and stability conditions have been obtained. The numerical results are compared with existing techniques, which demonstrate the effectiveness and applicability of the proposed technique. The proposed method has been applied to four numerical test problems at various time levels and mesh sizes to demonstrate the effectiveness, which involves quadratic, cubic, and quartic order nonlinear terms. The comparison shows good agreement with the exact solution, as demonstrated by absolute error tables and graphs. Moreover, the proposed method is easy to implement and produces good results.

Satish M Dhoke

India’s Goods and Services Tax, introduced in 2017, was envisioned as a transformative reform to unify indirect taxation and foster competitiveness. However, compliance burdens, multiple tax slabs, and frequent rule changes continue to limit efficiency. This study examines the impact of next-generation GST reform, including compliance simplification, slab rationalization, and digital automation, on the ease of doing business and competitiveness, with a focus on enterprises in the state of Maharashtra. A mixed-methods design combined survey data from 200 GST-registered businesses with expert interviews. Findings indicate that rationalization significantly improves operational efficiency, reduces transaction costs, and strengthens competitiveness, with digital automation emerging as the strongest predictor. The study concludes that GST rationalization is not merely an administrative adjustment but a strategic imperative for India’s economic growth.

Yanzhen Liu, Yang Liu, Fengfeng Feng et al.

Block copolymers with diverse compositions and topologies can self-assemble into multi-hierarchical structures, yielding materials with a wide range of functional properties. By adjusting external stimuli such as temperature, solvent polarity, mechanical force, and light exposure, these polymers form various nanostructures—including nanocrystals, micelles, and vesicles in solution; spherical, cylindrical, and lamellar microphases in bulk; and even “fractal” morphologies at interfaces. These hierarchical materials exhibit tailored functionality based on molecular design, enabling broad applications in nanomedicine, electronic devices, optical elements, and catalytic systems. In this review, we first summarize synthetic strategies for block copolymers with varying compositions and architectures. We then discuss their self-assembly behaviors and resulting nanoscale morphologies in bulk, solution, and interfacial environments. Several representative examples of assembled block copolymer systems and their practical applications are highlighted. Finally, we offer perspectives on future developments in the fabrication and application of block copolymer-based nanomaterials. This review provides an overview of strategies and examples for constructing precision nanostructures via block copolymer self-assembly, aiming to inspire further advances in nanomanufacturing technologies.

Jamshad Ahmad, Khalid Masood, Fatima Ayub et al.

Abstract The Zakharov–Kuznetsov–Benjamin–Bona–Mahony equation (ZKBBME) is a crucial mathematical model used in fractional quantum mechanics, optical fiber signal processing, ion-acoustic waves in plasma, water waves driven by gravity, turbulent flow, fluid flow waves, and for describing many other real-world phenomena. This article employs the modified exp-function method and exp $$(-\Phi (\psi ))$$ -expansion method, along with a truncated M-fractional wave transformation, to investigate new rational, trigonometric, hyperbolic, and exponential function solutions. Assigning specific parameter values generates diverse wave shapes most significantly, a new combined wave type called the compacton-kink and a class of peakon waves, which has not yet been documented in previous research of this model. 2-dimensional, 3-dimensional, contour, density, and polar plots illustrate the physical properties of soliton solutions, demonstrating the method’s suitability for analyzing a range of nonlinear fractional models with truncated M-fractional derivative (TMFD). Furthermore, utilizing the Galilean transformation to transform the equation into a planar dynamical system, bifurcation theory is applied to investigate its bifurcation and equilibrium points. The findings show that the TMFD framework captures intricate nonlinear wave dynamics and considerably enriches the ZKBBME solution space. These results advance our knowledge of wave structures in engineering and applied physics models controlled by fractional-order nonlinear partial differential equations (FNLPDEs).

Usha C

Forensic accounting has emerged as an important area of study in commerce education due to the increasing complexity of financial fraud and corporate malpractice. The present study examines the awareness, curriculum inclusion, resource availability, and overall effectiveness of forensic accounting education among academicians and students of higher education institutions in Karnataka. Primary data were collected using a structured questionnaire from 189 academicians and 180 students through a Google Form survey. A quantitative approach was adopted, and the data were analysed using reliability analysis, one-sample t-test, and multiple regression techniques. The findings of the study reveal that curriculum inclusion has the highest impact on the effectiveness of forensic accounting education, followed by awareness and resource availability. The regression model indicates a strong relationship among the variables, explaining 90 percent of the variation in effectiveness. The results highlight the need to strengthen forensic accounting education through structured curriculum integration, awareness programmes, and adequate institutional support. The study concludes that enhancing forensic accounting education can equip students with essential skills for fraud detection and financial investigation, thereby improving their professional readiness in commerce.

C. Matteo, I. B. Sayavur

The bone marrow microcirculatory system's present challenges for experimental investigation due to its complexity and limited accessibility. This study employs Computational Fluid Dynamics (CFD) to model blood flow within the myeloid sinusoidal capillaries of mice femur bone, focusing on velocity profiles, pressure distributions, and wall shear stresses. Using ANSYS Fluent 2023 R2, a detailed computational domain was developed from microscopic focus-stacked images, with a robust unstructured mesh applied for precise flow simulations. Blood was modeled as a multiphase Eulerian mixture, accounting for plasma and red blood cell dynamics. Results were validated against experimental data, showing a good agreement in velocity, volume fractions, and wall shear stress distributions. These findings underline the capability of CFD in providing detailed insights into microvascular blood flow, supporting future studies on hematological disorders and bone marrow mechanics.

Shixuan Li, Leshi Shu, Ping Jiang et al.

Laser lap welding of dissimilar Al–Cu metals is increasingly applied in electrical interconnections and power battery manufacturing for new energy vehicles due to the high conductivity of copper and the lightweight, high-strength properties of aluminum. However, their distinct physical characteristics, including melting point, thermal conductivity, and laser absorptivity, induce severe penetration depth fluctuations during welding, which deteriorate joint performance. To address this challenge, a multi-signal fusion approach is proposed for predicting penetration fluctuations. Real-time keyhole depth signals are captured via optical coherence tomography (OCT), while electron temperature is derived from plasma plume spectra, forming multi-source descriptors of molten pool dynamics. After feature extraction, a backpropagation neural network (BPNN) is developed. Experimental validation shows that the model achieves an average prediction error of 0.0448 mm. The proposed method provides a reliable tool for quality control and defect prevention in Al–Cu dissimilar metal laser welding.

Bamadev Sahoo, Sanjaya K Mohanty, A. K. Pany et al.

This study examines the analytical investigation of nonlinear wave structures governed by a Schamel-type Korteweg-de Vries (S-KdV) equation, essential in plasma physics for modelling ion-acoustic waves. This work is motivated by the necessity to enhance understanding of the impact of electron trapping effects on solitary wave dynamics. We employ the Extended Direct Algebraic (EDA) method to derive precise wave solutions. The applied method offers a systematic approach to derive various soliton structures and improves our comprehension of their physical properties. In plasma physics, the S-KdV equation is utilised to examine dust ion acoustic waves. Furthermore, it is employed to examine shallow water waves distinguished by steepening and breaking. It is applied in studying the Earth's magnetosphere, the solar wind, the nonlinear plasma turbulence, and the dusty space plasma. Graphical and comparative analyses are presented to validate the results and demonstrate the robustness of the method. The obtained solutions for the S-KdV equation have Kink type, anti-kink type, and multisoliton and solitary wave structures. The properties of the wave structures are demonstrated through the two-dimensional, three-dimensional, and contour plots. Additionally, the impact of the nonlinear term as well as the dispersion term on some of the obtained solutions are discussed through the two dimensional plots.

Wenyan Shi, Jiajing Lin, Rui Da et al.

Chemical enhancement in surface-enhanced Raman scattering (SERS) enables detection specificity by leveraging charge transfer (CT) between substrates and adsorbed molecules, a mechanism pivotal for designing next-generation SERS sensors with ultraselective molecular recognition capabilities. In this paper, based on the defect engineering, a Co-doped TiO2 film was prepared by the sol-gel method and spark plasma sintering furnace (SPS) approach. Multimodal characterizations (X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), ultraviolet photoelectron spectrometry (UPS)) combined with the three-dimensional (3D) finite-difference time-domain (FDTD) simulation results reveal that Co doping enhances the Raman signal intensity via introducing oxygen vacancies and optimizes energy-level alignment. Innovatively, the charge transfer dynamics measured by ultrafast time-resolved photoluminescence spectroscopy (TRPL) further confirmed the superior carrier transfer property of the Co-doped TiO2 films. Importantly, the coexistence of two charge transfer pathways were explored: direct charge transfer from Co0.05Ti0.95O2 to R6G and charge transfer mediated by defect states generated through ultraviolet (UV) irradiation, which can significantly enhance the SERS sensitivity. The SERS substrate based on oxygen vacancy-engineered Co0.05Ti0.95O2 demonstrates an excellent sensitivity and recycling performance. The EF of R6G adsorbed on optimized Co0.05Ti0.95O2 with little Au is about 1.13 × 108, and the LOD is about 7.9 × 10-10 M with Rhodamine 6G (R6G) as the probe molecule. Furthermore, the highly ordered bowl-like ConTi1-nO2 arrays were prepared by photolithography, which exhibit superior stability, and the RSD of Rhodamine 6G (R6G) is about 3.6%.

Mohamed R. Ali, M. Khattab, S. Mabrouk

The Landau-Ginzburg-Higgs (LGH) equation explains the ocean engineering models, superconductivity and drift cyclotron waves in radially inhomogeneous plasma for coherent ion-cyclotron waves. In this paper, with a simple modification of the Ablowitz-Kaup-Newell-Segur (AKNS) formalism, the integrability of LGH equation is proved by deriving the Lax pair. Hence for that, the inverse scattering transformation (IST) is applied, and the travelling wave solutions are obtained and graphically represented in 2d and 3d profiles.

M. Al Nasser, E. Karimi-Sibaki, M. Wu et al.

We present a 3D numerical model capable of simulating hydrogen electric arc. The numerical model couples the electromagnetic field with hydrogen plasma arc dynamics (flow and heat transfer). Electric arc operates under the conditions of atmospheric pressure using direct current (DC) in the presence of external magnetic field. It is found that arc instabilities emerge spontaneously near the cathode before propagating downwards along the arc jet. Also, spontaneous splitting into several arcs is observed before merging again into one arc. The horizontal magnetic field induces arc skewing and directional flow perpendicular to the applied magnetic field. However, the axial magnetic field induces a rotational flow and arc swirling.

M. Asaduzzaman, M. Mamun, A. Mamun

A rigorous theoretical investigation has been carried out on the propagation of non-linear self-gravitational shock waves (SGSHWs) in a magnetized super dense degenerate quantum plasma system (DQPS) composed of inertia-less non-relativistic degenerate electrons and inertial non-degenerate extremely heavy nuclei/element. The nonlinear propagation of these SGSHWs in the plasma system under consideration is studied by the standard reductive perturbation technique, which is valid for a small finite amplitude limit. The nonlinear dynamics of the SGSHWs are found to be governed by the Burgers equation. The Burgers equation is derived analytically and solved numerically. It has been found that the considered plasma model supports positive potential shock waves only. The fundamental properties (amplitude, steepness, etc.) of these SGSHWs are significantly modified by the variation of kinematic viscosity, obliqueness and number density of the plasma species.  The results of our present investigation can be applied to astrophysical compact objects like neutron stars. Journal of Engineering Science 15(1), 2024, 21-29

Malavika M P, V Tamil Selvi

Disability studies is an interdisciplinary field of studies based on the grounds of humanities and social sciences rather than viewing disability through the prism of medicine or psychology. It is an academic discipline that surfaced in the late 20th century, emanating from the disability rights movement and critical theory. This paper tries to examine Preeti Monga’s novels, The Other Senses: An Inspiring True Story of a Visually Impaired and Flight Without Sight, considering disability studies, marginalization, and oppression that disable the experience of people in private and public lives.

Sayyed Nagulmeera, Nagul Shareef Shaik, G.Minni et al.

Alzheimer’s disease (AD) is a progressive neurological disorder characterised by cognitive decline and memory loss. Early diagnosis is essential for effective treatment, although the complexity of the initial symptoms sometimes delays it. This review addresses the development of a deep learning-based model to aid in the early diagnosis of Alzheimer’s disease using neuroimaging data. Using MRI and PET scans from public datasets such as the Alzheimer’s Disease Neuroimaging Initiative, the proposed version makes use of convolutional neural networks (CNNs) to extract feature extraction and types by looking at brain structure in and on models associated with early Alzheimer’s ailment at the version that tries to decide the values ​​Performance is measured using key parameters along with sensitivity, specificity, accuracy, and area under the curve. The purpose is to develop a predictive tool which could help medical doctors diagnose Alzheimer’s disorder in advance and, in all likelihood, enhance the affected person’s effects via timely intervention.

Sanjeevni Gangwani

The trade practices in Saudi Arabia include farming, date exports, and trade generated by pilgrims. There was less economic growth. However, the oil exports and earnings from the oil sector generated funds for economic development, which helped international trade to flourish in the Kingdom of Saudi Arabia (KSA). The present study sheds light on the economic transformation of the KSA due to its sustainable trade practices. A qualitative methodology approach of the resource-based view was carried out in the international context. The present study discussed KSA’s initiatives to boost international business, including the Future Investment Initiative and the creation of small and medium-sized enterprises (SMEs). The study will evaluate the international business practices and economic transformation in KSA. This study will present the Saudi business environment and the government’s contribution to the country’s economic transformation.

Tahreem Noor Khan

The Marshmallow Challenge, a popular activity in classrooms and team-building exercises in offices promotes teamwork, communication, and collaboration. Despite its widespread use, its application within the Saudi educational context remains underexplored. Therefore, this research delves into the experiences and perceptions of 43 Saudi female undergraduate students participating in the Marshmallow Challenge in Organizational Behaviour (OB) class at the University of Hail, Saudi Arabia. Utilizing semi-structured interviews, the study aims to understand the nuances of this experiential learning activity, focusing on teamwork, communication, leadership, collaboration, and related responses. The findings reveal a spectrum of reactions from initial apprehension and nervousness to subsequent collaborative problem-solving and reflection. Ultimately, this research paper contributes to the broader literature on experiential learning in OB education, offering educators actionable insights to optimize student engagement, collaboration, and skill learning.

Vakula Bharathi Geddam, Ch. Sivanarayana, P. Gnanamoorthy

Concrete plays a pivotal role in construction, and the quest to enhance its performance and sustainability is ongoing. Aggregates, comprising 70-80% of concrete, are traditionally made of crushed rocks as coarse aggregates and river sand as fine aggregates. However, increasing demand for these natural resources due to growing construction activities has escalated costs and raised environmental concerns. This study investigates the potential of using Oil Palm Shell (OPS) as a partial replacement for coarse aggregates and Manufactured Sand (M Sand) as a substitute for fine aggregates in M30 grade concrete. Furthermore, the study examines how these replacements affect the concrete’s properties when exposed to elevated temperatures. Various tests were conducted to evaluate slump, split tensile strength, compressive strength, and flexural strength of concrete specimens after 7, 14, and 28 days of curing. Concrete samples were prepared with varying proportions of OPS (5%, 10%, and 15%) and M Sand (10%, 20%, and 30%), along with combinations of both. The results indicated that the inclusion of OPS and M Sand improved the concrete’s strength properties, with certain mixtures outperforming conventional concrete. The analysis of these outcomes underscores the factors contributing to the enhanced strength, demonstrating the potential of OPS and M Sand in boosting the durability and sustainability of concrete structures. Adopting these materials not only reduces construction costs but also promotes environmentally sustainable practices within the construction industry.