bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on chemical kinetics of plasma-assisted energetic material combustion
Authors: Guo J T , Yang C X
Published: December 2024

The combustion kinetic mechanism of C4H8N8O8(HMX) is established, with 30 components and 94 reactions. To account for the effects of plasma ignition and assisted combustion, the model incorporates reactions involving H free radicals at varying mole fractions. The thermodynamic parameters of products and combustion pathways of HMX are analysed by using Chemkin. The result of sensitivity analysis shows that the reaction of N2O+H=OH+N2 has a great influence on the ignition delay time. H and OH radicals play a positive role in ignition, while OH has higher activity than H. The sensitivity analysis of OH shows that N2O+H=OH+N2 has high sensitivity and highest reaction rate. As the mole fraction of H in the reaction chamber increases, the generation rate of OH increases. The reaction rate at 0.2 mole concentration of H is twice higher than 0.1 mole concentration. The increase of OH mole fraction increases the reactivity and decreases the ignition delay time.
Based on supercritical carbon dioxide projectile launch technology research
Authors: Tao Jie , Yang Chunxia , Han Shuyong , Wang Jian , Wang Qifan
Published: December 2024

In order to expand the application of compact high-velocity gas cannons in the field and hazardous areas, this paper proposes a new type of one-stage gas cannon with supercritical carbon dioxide as the gas medium. FLUENT numerical simulation method was used to study the gun bore firing process. Based on the projectile force, projectile velocity and flow field cloud diagram, the firing characteristics of the gas gun were analysed. The effects of different structures, different initial pressures and projectile masses on the firing performance were investigated. In order to verify the accuracy of the simulation model, a supercritical carbon dioxide gas cannon experimental test platform was built. The results show that the pressure in the chamber of the gas cannon with stacked arrangement structure fluctuates. Increasing the initial pressure and reducing the mass of the projectile can increase the initial velocity of the projectile. The greater the initial pressure is, the greater the pressure loss is under the stacked arrangement. There is a certain matching relationship between the thickness of the diaphragm, the filling amount of liquid carbon dioxide and the amount of heating charge. The amount of heating charge and the remaining thickness of the diaphragm have a greater impact on the launch performance of the gas cannon than the mass of liquid carbon dioxide.
Microstructural Evolution and Mechanical Property Enhancement in WAAM Components
Authors: Cheepu Muralimohan , Yenumula Padmini , Kantumuchu Venkata Charan , Annapureddy Damodara Reddy
Published: December 2024

Wire arc additive manufacturing (WAAM) is increasingly being recognized as a favourable method for producing large-scale products. The microstructural evolution during the solidification of molten pool in WAAM is influenced by factors such as heat input and the deposited layer sequence. In this study, the impact of different layering sequences on grain growth, microstructure, and mechanical properties was investigated by depositing Inconel 825 alloy using gas metal arc welding. Different layering sequences were employed to minimize the development of columnar grains that typically outcome from oscillating beads and bead upon bead within a single layer. The unidirectional heat flow in conventional layering techniques encourages grain growth in the direction of the heat source, with grains forming at the fusion boundaries and growing upwards. At the interface between previously solidified beads and the liquid metal, nucleation and epitaxial grain growth occur, prominent to the formation of transverse columnar grains, with their size determined by the grain structure of the preceding layer. While traditional stacking sequences tend to produce columnar grains, a zigzag layering approach was found to refine grain growth by disrupting the direction of heat flow and grain development. This resulted in smaller, more fragmented grains, which enhanced the isotropic properties of the material. The study further demonstrated that the anisotropic behavior of wire arc additively manufactured components is closely related to grain growth direction and size, both of which are significantly influenced by the layering sequence. The zigzag layering sequence not only improved hardness and tensile strength compared to conventional layering methods but also enhanced the resolution and linearity of the deposited walls.
Lightweight design of cannon frame considering dimension and topology coupling
Authors: Wang Meng , Hu Dan , Zhao Jiayu , Gong Borui , Hao Chengye , Lin Wenqi
Published: December 2024

The cannon frame is a primary load-bearing component of the firepower system, and lightweight design plays an important role improving the artillery’s manoeuvrability. However, the present lightweight design methods don’t consider the interdependency between dimension and topology, hindering the cannon frame from achieving the ideal stiffness to mass ratio. To tackle this issue, a novel lightweight design methodology considering dimension and topology coupling is proposed. By means of orthogonal experiment and topology optimization, various topologies of cannon frame with distinct dimensions are generated. Then the response surface method (RSM) is implemented to devise surrogate models that embody dimension, topologies, stiffness and mass mapping. Finally, global optimization is performed using particle swarm optimization (PSO) algorithm to achieve the concurrent lightweight design of dimension and topology. Compared with the original scheme, the proposed design method reduces the weight by 12.7%.
Research on the dynamic characterization of hydraulic buffer based on gene expression programming approach
Authors: Tan Tian , Dai Jin-song , Zhang Yong-tao , Meng Chao , Lin Sheng-ye
Published: December 2024

This paper is devoted to the dynamic characterization of the autocannon buffer through the surrogate model technique. Autocannon is usually equipped with spring hydraulic buffers, and flow field analysis based on numerical simulation is the focus of buffer characteristic research. However, commercial software is generally computationally expensive and challenging to interact with system dynamic models. To end these, this paper proposes constructing a surrogate model through the gene expression programming (GEP) approach and embedding it into the autocannon bond space model for recoil process analysis. The dataset for the GEP model is derived from the fluid pressure simulation based on computational fluid dynamics (CFD). By this, the buffer surrogate model is bonded to the firing dynamic model by a power bond formed by recoil velocity and hydraulic pressure. Moreover, an engineering example of an autocannon buffer is presented to demonstrate the validity of the proposed method; the analysis results show that the Pearson correlation coefficients between the GEP model and the training and testing sets are 0.99 and 0.98, respectively. The calculated recoil force extremum and recoil velocity are consistent with the experimental results.
Coupling Valve Opening and Closing Effects on Compressed Air Ejection System Projectile Launch Study
Authors: Tao Y , Zhang P , Yang C H , Ma W N , Zhang Z D , Zheng X L
Published: December 2024

Based on the working principles of high-pressure pneumatic pilot-operated valve (HPPV) and compressed air ejection device, a multi-physics simulation model of the compressed air ejection device considering pneumatic, mechanical, and leakage factors was established in AMEsim. A compressed air ejection test platform was also constructed to conduct unloaded tests. The validated simulation model investigated the impact of different initial parameters on the dynamic characteristics of the HPPV during the compressed air ejection process. The results demonstrate that the multi-physics simulation model of the coupled valve opening and closing exhibits high computational accuracy. During the compressed air ejection process, the dynamic characteristics of the HPPV still meet the requirements of the compressed air ejection device, effectively preventing ineffective gas leakage. The initial pressure of the ejection gas source and the supply pressure driving the HPPV significantly influence the dynamic characteristics of the valve during the compressed air ejection process.
FSK energy modulation integrated primer fuze technology based on S-P topology
Authors: Chang Hao , Yang Zhen , Yu Weixing , Fang Wei , Wang Guoqiang , Liu Chang , Zhang Yifan , Jiang Zhiqiang
Published: December 2024

The wireless energy transmission technology is utilized in the integrated primer fuze device to achieve the integrated transmission of energy and information for weapon equipment. A wireless energy and information transmission system model is designed specifically for the characteristics of energy and information transmission of integrated priming fuze. The working principle of the system under S-P magnetic coupling resonance is analyzed, and the inverter circuit and rectifier circuit are further designed. To achieve synchronous transmission of energy and information, an energy modulation/demodulation method based on FSK is proposed. Simulation verifies the feasibility of the system design, showing that while the S-P system has a simple structure and constant voltage output characteristics, it belongs to first-order resonance. When transmitting information through frequency modulation, there will be a reduction in system transmission efficiency due to deviation from the resonance point, making it only suitable for systems with small energy transmission requirements.
Research on the influence of cavitator configuration on the cavitation flow characteristics around projectiles
Authors: Qi Xiaobin , Xia Fangchao , Wang Jiawen , Liu Huan
Published: December 2024

In order to optimize the projectile head shape, numerical simulations were conducted on the cavitation flow field of different cavitator configurations, including inverted trapezium, hemispherical, and cylindrical cavitator configurations. The results indicate that under the same cavitation number, the inverted trapezium cavitator produces the largest cavitation profile and is more prone to cavitation generation. Cylindrical cavitator come in second place, while hemispherical cavitator are less prone to cavitation. The turbulent kinetic energy is closely related to the generation of cavities, and the turbulent kinetic energy is highest near the inverted trapezium cavitator, so its bubble size is also the largest. The diameter ratio between the smaller and larger bottom surfaces of the inverted trapezoidal cavitator has a significant impact on the high-speed cavitation flow around the projectile. As this ratio increases, the thickness of the cavity increases, but it also leads to a significant increase in the navigation resistance coefficient. Overall, the inverted trapezium cavitator is easier to generate cavitation and can provide support for the optimal design scheme of supercavitating projectiles.
A refined prediction model for the initial disturbances of the projectile in the self-propelled gun
Authors: Dong X , Rui X , Yang F , Zhang S
Published: December 2024

In the gun launch process, the continuous propellant combustion provides power and energy for the projectile. Due to the gap between the projectile and barrel, the high-speed motion of the former is generally accompanied by contact and collision with the latter. Meanwhile, the gun also recoils under the propellant gas. Notably, the above complex motion of the system causes the initial disturbances of the projectile and muzzle. Previous launch dynamic models usually neglect the influence of the gun recoil on the combustion and flow in the chamber. However, the gun recoil inevitably further increases the chamber’s free space, resulting in the calculation deviations of projectile and muzzle disturbances. The above deviations ultimately determine the firing accuracy and firing stability prediction. To study the in-bore projectile motion and subsequent external ballistic process more accurately, an improved coupled calculation method of launch dynamics is developed. This work combines the interior ballistic two-phase flow dynamics considering the gun recoil, in-bore projectile motion theory, multibody system dynamics, and necessary high-precision numerical schemes. The launch process of the 155 mm self-propelled gun is studied. As the results show, the calculated vibration characteristics, dynamic response, and interior ballistic performance indexes are consistent with measured ones, verifying the feasibility of the above method. In addition, the initial disturbances of the projectile with and without considering the recoil’s influence on the combustion and flow in the chamber is discussed. The work in this paper provides an accurate tool to predict the initial disturbances of the projectile.
Principle of fault direction discrimination in near area of AC grid-connected doubly-fed wind farm
Authors: Qiu Jingran , Wen Minghao , Qian Kun , Zhang Kaize
Published: December 2024

With a large number of new energy sources, the current characteristics of doubly-fed fans under the circumstances of AC grid connection short-circuit faults have become the focus of research. After crowbar resistance is put in, the attributes of short-circuit current become complicated. By calculating the correlation coefficient between the voltage of the AC system and the current of the doubly-fed fan, the fault direction can be accurately judged. In this paper, the research work for new energy power system fault analysis and protection provides a new thought and method. The current characteristics of the doubly-fed fan under fault state are analyzed deeply, and the principle of fault direction discrimination based on waveform correlation coefficient is proposed. The advantage of this method is that it is independent of fault types, and can be applied to all kinds of fault situations, with high reliability and practicability. Simulation results unveil that the principle put forward can judge the fault direction accurately, reliably, and sensitively when various types of faults occur in areas near an AC grid-connected doubly-fed wind farm.
Coupling mechanism for total transfer capability of transmission interface with transient overvoltage constraint
Authors: Tang Xuelin , Liu Qihui , Wu Linlin , Liu Hui , Xu Man
Published: December 2024

To explore the correlation between transient overvoltage (TOV) and total transfer capability (TTC), and clarify the coupling law of multi-level transmission interface TTC, this paper first analyses the mechanism of TOV under AC symmetrical faults in high-proportion power electronic systems, derives a TTC analysis model considering TOV constraints, and examines the relationship between output power and TOV. Based on this model, the coupling mechanism of the coupled interface TTC is further analyzed. The coupling laws of the interface TTC are obtained. Finally, the validity of the theoretical analysis is verified through time-domain simulations.
A Flexibility Enhancement Approach for Integrated Electric-Gas Energy Systems Considering Incentive-Based Demand Response
Authors: Zheng Wenzhang , Li Qiang , Yang Ming , Yu Yixiao , Feng Yankun , Lu Rui
Published: December 2024

In the context of large-scale grid-connected renewables, the flexible and economic operation of the power system faces greater risks. The incorporation of user-side resources can reduce the strain on the power supply from the source; the coupling of heterogeneous energy flows in the integrated electric-gas energy system (IES) can provide the power system with greater flexibility in regulation. In this paper, we first analyze the dynamic characteristics of the natural gas network and perform mathematical modeling to clarify the interaction mechanism between the electricity and gas grid. Following this, the power network is analyzed for sensitivity, and demand response contracts are signed with industrial, commercial, and residential users to determine the amount of load shedding and compensation costs for each node user. Finally, an arithmetic validation is carried out on the E24-G20 nodal system, which demonstrates the efficacy of the proposed plans through the curve of pipe storage and the reduction of the lost load volume.
Transient overvoltage control strategy based on improved VDCOL curve for AC-DC system
Authors: Wang Jiaqi , Li Yinghui , Wang Yupeng
Published: December 2024

In order to suppress the transient overvoltage at the bus bar of the transmission terminal of the AC-DC system, a transient overvoltage suppression strategy based on an improved VDCOL curve is proposed. Firstly, the expression of transient overvoltage is derived based on the DC short-circuit ratio, and then an evaluation index of transient overvoltage is proposed according to the standard of overvoltage. Then, according to the control curve design principle of VDCOL, an improved VDCOL curve based on the Tanh function is proposed. Finally, this suppression strategy is used to suppress the transient overvoltage at the bus terminal. Through the actual network data verification, the results show that the improved VDCOL curve has a better suppression effect on transient voltage than the traditional control curve, which proves that the strategy has higher applicability.
Research on the limit prevention system for near electric operations in power transmission and transformation engineering based on pulse radiation
Authors: Shi Changyun , He Yongjun , Zhang Bin , Chen Li , Liu Yingnan
Published: December 2024

To solve the problems of high risk and low efficiency in manual control of near electric operation construction, this paper proposes a pulse ray based near electric operation anti limit system for power transmission and transformation engineering. The software and hardware of the system are designed according to the functional requirements of the system. By using a pulse laser module to detect whether there is object intrusion in the near electric work area, the on-site construction safety control distance is obtained by setting the voltage level. When there is object intrusion, both the on-site and system backend will sound an alarm simultaneously. Through on-site testing, the accuracy of object intrusion warning is 100%, successfully solving the problem of the lack of intelligent control measures in near electric operations, achieving autonomous control, precise detection, and real-time warning of near electric operations.
Optimization method for grid forming control oriented to large-scale new energy grid connection
Authors: Gong Xianfu , Lu Xun , Wang Peng
Published: December 2024

The integration of substantial new energy sources into the traditional AC power grid introduces several disturbances and failures. These include fluctuations in new energy output in the sending-end grid, high-power failures in AC/DC transmission channels, and DC commutation failures. These issues pose significant challenges to the transmission efficiency and stability of the grid, gradually revealing numerous limitations. To address these challenges, this paper presents an optimization method for grid forming control tailored to large-scale new energy integration. Firstly, a voltage source converter-multi-terminal direct current (VSC-MTDC) multi-margin droop control approach is introduced to optimize converter station operations and improve system responsiveness to changes in DC network power flow. Secondly, a VSC-oriented grid forming power flow optimization problem is formulated. Finally, an optimization method of grid forming control for new energy grid connection is presented, utilizing the jellyfish search algorithm to solve the optimization problem. Simulation results show that this approach effectively improves the system’s operational efficiency and stability.
Voltage regulation control of three-stage synchronous generator based on modified differential evolution algorithm
Authors: Zhang Chengyu , Lv Xiaoxian , Pu Chengnan
Published: December 2024

In modern aviation power systems, the dynamic stability of power generation systems has become a major challenge. To tackle issues such as slow response, poor voltage stability, and voltage oscillations in aircraft synchronous generators under sudden load changes, a Proportional-Integral-Derivative (PID) voltage regulator modified using the Differential Evolution (DE) algorithm has been developed. Additionally, the DE algorithm’s convergence speed and robustness are enhanced through the incorporation of directional search strategies and adaptive control parameters. Simulation results demonstrate that the optimized regulator delivers rapid response and minimal overshoot, thereby improving the accuracy and dynamic performance of the voltage regulator. The modified DE algorithm notably accelerates convergence compared to the traditional DE algorithm.
Improvement of the control performance of cable AC voltage withstand testers
Authors: Chen Longxiao , Zhu Zhien , Yang Lingming , Gao Kai , Song Pengxian
Published: December 2024

The traditional cable AC withstand voltage test device has poor control accuracy and slow protection performance, and the inverter based on power switching devices can be applied to the test device to effectively solve the above problems. However, the LCL-type inverter contains resonance, which tends to cause system destabilization and reduces current quality, affecting the effectiveness of the device for testing. Differential feedback filter capacitor voltage can solve the problem and can save a high-accuracy sensor, but the differential limits its application. This paper proposes to use the negative-band pass filter (NBPF) connected to lag correction (LC) link to equivalent the differential, and it can not only effectively suppress the resonance, but also can significantly suppress high-frequency noise. An experimental platform is built for validation.
A modified P&O maximum power tracking control algorithm for independent wind energy conversion system
Authors: Wang Hui , Ma Pengfei , Hu Guang , Wang Haifeng , Zhou Yunyi , Jiang Zaiyong
Published: December 2024

A maximum power point tracking (MPPT) algorithm based on the three-point method is proposed in this paper, designed to improve the traditional perturb and observe (P&O) method, which often struggles to balance both dynamic and steady-state system performance. Initially, the P&O method is utilized to quickly approach the vicinity of the point where the power is max. Subsequently, the three-point method is employed to adjust the duty cycle based on historical step size and power changes, allowing the system to smoothly track the MPP and reduce oscillations. A direct-drive permanent magnet synchronous wind turbine is used as the verification object, and a simulation model incorporating uncontrolled rectification and a Boost converter is established. The algorithm is compared with traditional methods in terms of duty cycle, output power, and wind energy utilization. Results demonstrate that the proposed algorithm significantly enhances dynamic response speed, reduces system oscillations, and improves wind energy utilization efficiency compared to the conventional P&O method.
TOPSIS approach based adaptability analysis for power substation area communication schemes
Authors: Wang Qi , Song Yanbin , Lin Zhifeng , Wang Wanqiao , Guan Luyao , Ding Huixia
Published: December 2024

With the development of new power systems, various new services emerge in substation areas, increasing the number of end devices as well as the frequency of data collection. As a result, end terminal communication in substation areas faces significant challenges such as capacity, coverage, reliability and so on. A unified analytical model is required to evaluate various networking schemes. Therefore, in this paper we propose a technique for order preference by similarity to an ideal solution (TOPSIS) based compatibility analysis model for power communication demand indicators, which provides a theoretical evaluation criteria for substation area communication networks. Based on the model, we also introduce multiple networking schemes for comparison. The comparative results show that for three typical services, emergency response, electric frequency regulation, and peak shaving, there are three distinct networking schemes with the highest compatibility, respectively. Wherein joint HPLC, HRF, and LTE networking provide well-suited performance for substation area communication.
Memristor & its application in biological field
Authors: Duwarah Himadri , Datta Pranayee
Published: December 2024

Demand for highly integrated, low-power nonvolatile memories to get beyond the drawbacks of traditional memory systems has led to, Memristive/resistive switching devices which are excellent choices for non-volatile memory technology. Memristor is the 4th fundamental unit proposed by Professor Chua to give a relation between charge and magnetic flux. If a memristor’s constitutive relation is a straight line with a slope of M that passes through the origin in the ɸ –q plane, it is considered linear. The memristor’s physical realizations and potential uses remain a fascinating area for investigation.Semiconductor nanoparticles specially ZnO, ZnS QD exhibit Memristive characteristics. Employing this Memristive behaviour of biofunctionalized nanoscale particles and “voltage gap” as a novel sensing metric, several investigators attempted to assess the precise amount of microbiological contamination. Here in this work, Memristive property of some semiconductor nanoparticles like ZnO, ZnS as well as metal nanoparticle like PbS, Ag particles are studied and tried to focus on application of Memristive devices in near future in biological fields. The switching properties of bio-voltage memristors can now be used to achieve bio-voltage matching.
Exploring interface sensitivity in pentacene: Waveguide analysis of circular current and induced magnetic field
Authors: Thakuria Doli , Deka Raktimjyoti , Ganguly Sudin
Published: December 2024

This study delves into the intricate influence of interface sensitivity on the transport properties of polyacenes, namely pentacene. The investigation focuses on transport currents, circular currents at various loops, and induced magnetic fields, examining their behaviors under diverse lead-to-polyacene geometries. The system is described within the nearest-neighbor tight-binding framework. Applying waveguide theory, we calculate the two-terminal transmission probability and the currents are computed using the Landauer-Buttiker formalism. This comprehensive exploration sheds light on the subtle relationship between interface sensitivity and the transport characteristics of polyacenes, providing valuable insights for future advancements in molecular electronics.
Time Variable G and Λ in Five Dimensional Bulk Viscous Cosmological Model with Functional form of Hubble Parameter
Authors: Ali Nawsad
Published: December 2024

In this article, we have constructed a spatially-flat Kaluza-Klein type cosmological model with the matter field narrated as bulk viscous fluid united with time dependent gravitational constant G and cosmological term Λ. The viscous coefficient η is taken as a quadratic form of Hubble parameter H (i.e. η = η
0 + η
1
H + η
2
H
2, where η
0 (≥ 0), η
1 and η
2 are constants). Exact generic solutions of the field equations are acquired with help of functional form of Hubble’s parameter, which yields initial deceleration to current time acceleration of the universe. Some geometrical and kinematical behaviours are analyzed.
Theoretical Analysis of Cosmological Constant and the Constraints of Varying Fine Structure Constant
Authors: Debnath Dipa , Bhowmik Anwesha , Choudhury Shaheb , Deb Priya , Ghosh Sovan
Published: December 2024

Cosmological constant is considered to be one of the most important factors in cosmology after the discovery of the presence of dark energy. The ratio of vacuum energy density to matter density is expressed as function of scale factor in a cosmological model. In the present article this model is tested with two different function of scale factor. Varying fine structure is a point of concern to the cosmological constant based dark energy models. Different constraints against variation of fine structure are surfaced. The constraints are discussed in terms of the considered model in the article. Here we have analyzed those constraints.
Dynamics of Positive Charge Particles in Saturn’s D68 Ringlet Under Gravitational and Electromagnetic Forces
Authors: Lianlunthang TD Peter , Baruah Monmoyuri
Published: December 2024

The dynamics of positive charge particles within Saturn’s D68 ringlet, influenced by gravity and electrodynamics, were numerically studied. Our findings show that the stability of the charged particles depends on both size and initial velocity. Smaller particles are more stable and maintain their orbits longer than larger ones. Similarly, those with slower initial velocities are more stable. 0.01 nm - 0.028 nm sized cations, launched with keplerian velocity get trapped in stable orbits around Saturn for years. Slightly larger ions, 0.029nm to 0.1 nm, are unstable and descend into Saturn’s atmosphere. Particles between 0.11 nm and 1 μm intersect with D72, potentially contributing to recycling ring materials. However, when launched at Saturn’s rotational speed none of them could escape. The 0.03 nm - 0.1 nm sized particles stably orbit the planet while the 0.04 nm - 1 μm sized move inward and collide with Saturn’s atmosphere. In both the launches, the motions are confined to the equatorial plane. The unstable ones oscillate above and below the equatorial plane as they move toward and away from Saturn. This equatorial confinement helps explain electron depletion and increased conductivity in Saturn’s ionosphere at the equator. The dispersion of charge particles across longitudes and radial distances highlights the role of the Lorentz force in sorting D-ring grains by size. Our results support the argument that charged particles in the gap between Saturn and its D ring originate from the D68 ringlet.
Optimization of leptonic CP violation search using baseline configurations in neutrino oscillation experiments
Authors: Nath Ankur , Son Cao Van , Thomas Jennifer , To Quyen Phan
Published: December 2024

One of the fundamental goals of the neutrino program over the next decade will be to look for leptonic CP violation and precisely determine its magnitude. Neutrino oscillation measurements are frequently conducted with a near-site detector for constraining the flux and neutrino interaction models and a far-site monolithic massive detector for measuring the oscillated spectrum pattern. In this work, we present an investigation of an alternative experimental configuration to improve the CP violation measurement sensitivity by using multiple sub-detectors while keeping the overall detector mass constant and placing them at different baselines. The study makes use of neutrino beams from the T2HK, DUNE and ESSνSB experiments. It is found that the coverage of true δCP
values that can be explored with ≥ 5σ C.L. improves significantly after deploying multiple far detectors, instead of the conventional single far-detector technique.
Fokas-Lenells Derivative nonlinear Schrödinger equation its associated fundamental forms and Gaussian curvature
Authors: Talukdar Sagardeep , Dutta Riki , Saharia Gautam Kumar , Nandy Sudipta
Published: December 2024

One of the most important tasks in mathematics and physics is to connect differential geometry and nonlinear differential equations. In the study of nonlinear optics, integrable nonlinear differential equations such as the nonlinear Schrödinger equation (NLSE) and higher-order NLSE (HNLSE) play crucial roles. Because of the medium’s balance between dispersion and nonlinearity, all of these systems display soliton solutions. The soliton surfaces, or manifolds, connected to these integrable systems hold significance in numerous areas of mathematics and physics. We examine the use of soliton theory in differential geometry in this paper. We build the two-dimensional soliton surface in the three-dimensional Euclidean space by taking into account the Fokas-Lenells Derivative nonlinear Schrödinger equation (also known as the gauged Fokas-Lenells equation). The same is constructed by us using the Sym-Tafel formula. The first and second fundamental forms, surface area, and Gaussian curvature are obtained using a lax representation of the gauged FLE.
Efficient supercontinuum spectra by non-Gaussian pulses
Authors: Barman Chandrika , Mazumder Krishanu Lal , Mukherjee Rohit , Borgohain Nitu
Published: December 2024

In this article, we examine the generation of supercontinuum spectra using various non-Gaussian pulses in semiconductor quantum wells. Specifically, we employ weak probe pulses modulated by a strong optical beam, leveraging electromagnetically induced transparency within the system. Our findings indicate that the characteristics of supercontinuum generation, as compared to traditional Gaussian pulses, differ significantly when non-Gaussian pulses, such as sinh-Gaussian, cosh-Gaussian, and tanh-Gaussian pulses are being used. Notably, among the pulses studied, the cosh-Gaussian pulse achieves the broadest supercontinuum span, reaching ~21 μm, at the end of the semiconductor quantum well. These results suggest potential applications in optoelectronic and photonic devices designed for spectroscopic analysis.
Fusion dynamics in the formation of 110Sn near and below the nominal barrier
Authors: Hitesh  , Ghanghas Vijay , Samiksha  , Singh Manjeet , Chahal Rishi Pal
Published: December 2024

In this paper, we examine the sublime nature of intrinsic channels originated due to nuclear structures of fusion participants at energies near and below nominal barrier. For abovementioned purpose, we study the fusion data of 46Ti + 64Ni and 50Ti + 60Ni nuclear reactions using symmetric asymmetric Gaussian barrier distribution (SAGBD) method. For studied fusion reaction, Wong result drastically fails around nominal barrier while SAGBD results appropriately recovered the shape of fusion excitation functions. The evaluated χ
2-values for studied reactions are also suggests the consistency of SAGBD model.
Fusion and decay study of Cadmium nucleus formed in Calcium induced reaction at energies lying around the Coulomb barrier
Authors: Kaur Jagdeep , Kaur Amandeep , Sharma Mahinderpal , Singh Birbikram , Gautam Manjeet Singh
Published: December 2024

The present investigation explores the fusion-fission phenomena in the field of nuclear physics, focusing particularly on their significance in astrophysical research, namely in the nucleosynthesis process occurring in the stars. The present work intends to investigate into the formations and fragmentation mechanisms of 104Cd* system, populated in the interaction of 40Ca and 64Ni ions at energies spanning the mutual electrostatic repulsion. For analysing the formation processes in complete fusion of 40Ca+64Ni channel, the fusion excitation functions are estimated via statistical CCFULL approach along with the dynamical model named as EDWSP. The dynamical effects are included via energy dependence. The fusion models suggests that it is imperative to include energy dependence and coupling effects to harmonize the experimental data. Furthermore, the Dynamical Cluster-decay Model (DCM) framework is exploited to scrutinized the fragmentation mechanism defining the decay of 104Cd*. The decay model suggests that the structure for evaporation residues and fission fragments gets altered by the incorporation of various angular momentum states. Other parameters such as nuclear deformations and neck-length parameter also pose influence on the structural aspects of decay profiles.
Assessment of indoor activity and its associated dose due to exposure to radon and thoron in dwelling.
Authors: Pyngrope A. , Sangma P. , Kakati Ranjan Kr
Published: December 2024

In the present study, assessment of indoor activity of radon and thoron is being carried out in dwellings of Duligaon area of Kokrajahar, Assam, using Solid state nuclear track based detector-Single entry Pin-hole dosimeter. The observed average indoor radon and thoron concentrations is found to be 246.06 Bq.m−3 and 44.08 Bq.m−3 respectively. Notably, these values are relatively higher than the global average which is 40 Bq.m−3 for radon and 10 Bq.m−3 for thoron. However these indoor metrics are within the acceptable range (200-300 Bq.m−3) as recommended by International Commission on Radiological Protection (ICRP). The estimated annual effective dose due to radon and thoron is estimated at 8.1 mSv.y−1, which is within the action limit (3-10 mSv.y−1) set by ICRP. We have also investigated the variation of radon and thoron activity in different house types, and using appropriate Seasonal Correction Factor (SCF), we have also estimated the seasonal activity of radon and thoron.
Enhancement in the dynamic range of an astigmatic defocus sensor through intensity measurement at two out-of-focus planes
Authors: Konwar Santanu
Published: December 2024

The astigmatic defocus sensor is effective for measuring low strength of defocus in the optical beam phase profile. But, the sensor fails in the presence of higher strength of defocus in the optical beam, i.e. its dynamic range is low. The paper propose a modified version of the conventional astigmatic defocus sensor capable of providing enhance dynamic range compared to that of a conventional sensor. The proposed sensor requires the intensity measurement at two out-of-focus plane. A comparative study in terms of dynamic range is carried out and simulation results showing enhance dynamic range are provided to validate the proposed technique.
A Comprehensive Study on Explainable AI Using YOLO and Post Hoc Method on Medical Diagnosis
Authors: Sarma Borah Proyash Paban , Kashyap Devraj , Laskar Ruhini Aktar , Sarmah Ankur Jyoti
Published: December 2024

Medical imaging plays a pivotal role in disease detection and intervention. The black-box nature of deep learning models, such as YOLOv8, creates challenges in interpreting their decisions. This paper presents a toolset to enhance interpretability in AI based diagnostics by integrating Explainable AI (XAI) techniques with YOLOv8. This paper explores implementation of post hoc methods, including Grad-CAM and Eigen CAM, to assist end users in understanding the decision making of the model. This comprehensive evaluation utilises CT-Datasets, demonstrating the efficacy of YOLOv8 for object detection in different medical fields. This paper compares the interpretability offered by different post hoc methods, shedding light on abnormalities detected by the model. Moreover, this paper introduces a user-friendly interface for end users, incorporating the generated heat maps for intuitive understanding using different CAM algorithms. These findings underscore the importance of XAI in medical image analysis and offer a practical framework for improving interpretability in X-ray diagnostics. The comparison of the different CAM methods can offer a choice for end users to determine the best fit for deployable tools. This work contributes to bridging the gap between sophisticated deep learning models and actionable insights for professionals. Access at https://spritan.github.io/YOLOv8_Explainer/
A Comparison of geomagnetic activity during the 24th Solar cycle to geomagnetic activities during the preceding solar cycles 19 to 23
Authors: Patowary Rashmi , Konwar Kanchan , Kuri Deep Kumar , Gogoi Sanat Kumar
Published: December 2024

Geomagnetic storms occurring during the period from 1957 to 2018 encompassing six Solar Cycles viz. cycle 19, 20, 21, 22, 23, and 24 have been identified by observing the hourly Dst indices from the World Data Centre Kyoto. The temporal variation of these storms in three different time scales viz. variation around a solar cycle, seasonal variation, and variation about solar rotation period were examined. Geomagnetic activity during the 24th cycle was found to be a cycle of unusually low geomagnetic activity as compared to other cycles of roughly the same solar activity, which can be attributed to absence of adequate interplanetary conditions in addition to absence of solar drivers. It was found that geomagnetic activity during the 24th solar cycle showed attributes more or less similar to those of cycles 19 to 23, though on a much smaller scale. Distinct equinoxial maxima with absence of asymmetry was found in case of seasonal variation. Storms occurring during solar minima indicated a peak around solar rotation period confirming the recurrent solar drivers.
Analysing the Execution of a Building Unifying with Concentrating Photovoltaic System and Phase Change Materials
Authors: Hussain Beporam Iftekhar , Vijayasekaran G , Sivaraman G , Maheskumar Pon. , Girimurugan R , Nanthakumar S
Published: December 2024

Building Unifying with Concentrating Photovoltaic (BUC-PV) systems are seamlessly incorporated into building envelopes, replacing traditional construction materials while offering benefits such as on-site electricity generation, enhanced radiant efficiency, and improved thermal management. This research introduces an innovative empirical assessment of Phase Change Materials (PCM) to enhance the efficiency of less-concentrated BUC-PV systems through heat transfer mechanisms. Unlike previous studies, which focused primarily on transient and spatial temperature analyses of PCM within constructed systems, this experiment examines the impact of paraffin-based PCM on the electrical energy output of the current setup. Addressing the limitations of the initial system, an advanced evaluation model is proposed and validated through controlled indoor experiments. Wax-based RT42 (paraffin) was used in a custom PCM enclosure. An indoor test was conducted using a steady irradiance of 950 W/m². Results demonstrated a 7.57% increase in electrical energy efficiency with the integration of PCM. Additionally, the BUC-PV-PCM system exhibited a mean module temperature reduction of 4°C compared to a PCM-less outdoor system. The experiment also revealed that PCM performance varied with irradiance flux density, showing an efficiency increase of 1.4% at 600 W/m², 5.0% at 700 W/m², and 7.0% at 950 W/m².
Enhancing Mechanical Performance and Heat Treatment Response in AA2024 Alloys Through B4C and Alumina
Authors: Ponnusamy Prasanth , Seenivasan S , Maheskumar Pon. , Girimurugan R , Krishnamurthy V P , Balasubramani S , Gowri K
Published: December 2024

Aluminum Alloy 2024/Boron carbide (B4C)/alumina composites showed different tensile characteristics after they were strengthened and heated. The T6 thermal cycle performance got better because the samples were made harder through “precipitation hardening” using various amounts of alumina and B4C. After the application of heat, the composite materials had a consistent spread of strengthening elements, and an examination of their energy levels showed Aluminum, Silicon, and Magnesium, along with small amounts of a few other particles. Researchers carefully tested the tensile properties of heat-treated and strengthened steel. The research indicated that both the tensile strength (TS) and yield strength (YS) increased to 210ºC and then started to decrease to 140ºC. The stiffness and elastic modulus of the composites improved due to the addition of reinforcement and heat treatment. This resulted in a significant reduction in El (Elongation) content in the composites. Several factors, such as the diffusion process, grain refinement, heat treatment temperatures, and the mix of strengthening elements, contributed to the enhanced elastic modulus and tensile strength of the composites. Research aimed at optimizing these findings to streamline the development of hybridized composite materials has many applications in the aerospace and transportation industries.
Comparative Analysis of Mechanical Properties in Hybrid Composites Using Neem and Indian almond Fiber
Authors: Ganapathy Srinivasan R , Priyadharsini S , Rajaravi C , Venkatesan R , Rathinasuriyan C , Harish K A
Published: December 2024

This study examines the mechanical properties and microstructural aspects of epoxy composites that have been reinforced with neem and Indian almond fibers. These fibers were first treated with a 5% NaOH solution by immersing them in it, leading to increasing surface roughness and improved bonding with the epoxy resin. Composite samples were made using the hand lay-up method, and a weight ratio utilized was 70:30 for resin-to-fiber. The tensile, flexural, impact, and wear strengths were analyzed in the testing profile of the composites. The composites were analyzed using FTIR spectroscopy and microstructural investigations to get insight into the interactions between the fibers and matrix, as well as the shape of the materials. Results showed that the tensile and flexural strengths had been improved significantly in comparison to the original epoxy material. It is, therefore, the results emanating from impact and wear tests, which rescue the endurance of these composites for application in the automobile and construction industries. The results indicate that the inclusion of natural fibers in polymer matrices not only improves mechanical performance but also promotes environmental sustainability.
Experimental Investigation on Microstructure Properties of Martensitic Stainless Steel Using Wire Pulse Arc Welding
Authors: pandian Alagu sundara , Pragadish N , Sengottaiyan K , John Stephen R , Selvam M , Ganapathy Srinivasan R
Published: December 2024

The present work is focused on the Wire Arc Additive Manufacturing process applied to 17-4 PH stainless steel, with regard to the understanding of microstructural and mechanical properties of as-deposited and heat-treated materials. It investigated uniformity in the fabricated components without any defects, which was found in the detailed microstructural analysis using scanning electron microscopy and X-ray diffraction. The results demonstrate a prevalence of columnar dendritic structures and high microstructural anisotropies mainly in the as-deposited state. Heat treatment effects were also explored, wherein variations in microstructure were noted to be associated with enhancements in mechanical properties, such as hardness. Results show that WAAM is able to produce high-quality parts that are optimized for performance in highly demanding applications. Micro hardness tests across the different regions of the components informed the microstructure-mechanical strength relationship, thus confirming that the WAAM process is suitable for producing parts with high mechanical strength and reliability for the aerospace sector and other stringent high-performance applications.
Effect of Tin Mining Waste as Sand Replacement on Flowability and Compressive Strength of Mortar
Authors: Ahmad N , Muthusamy K , Ruslan H N , Mohd Yunus M Y , Ismail M A
Published: December 2024

Environmental degradation due to excessive sand mining activity and tin tailing waste disposal from mining need to be resolved. Utilization of tin tailing as sand replacement in mortar production would cut amount of waste thrown and decrease river sand consumption. The current study examines the effect of tin tailing content sand replacement on flowability and strength of mortar. Five forms of mixes were produced using different percentage of tin tailing as fine aggregate replacement. Two types of tests were conducted namely flowability test and compressive strength test. The investigation discovers that blending tin tailing affects the flowability of mortar. Utilization of up to 30% tin tailing able to produce mortar with the targeted strength. Usage of high amount of tin tailing causes declination of mortar strength. Recycling tin tailing for use in mortar production saves the use of natural sand and reduce waste disposal.