Pundra University of Science and Technology

We define Vm,n in this article by using Ramanujan's product of theta-functions psi(-q) and f(-q^2), which are analogues to Ramanujan's amazing product of theta-functions. For explicit evaluations of Vm,n, we prove general theorems.

The need for intelligent traffic management solutions is crucial in the rapidly evolving fields of autonomous traffic control and navigation systems, particularly for minimizing traffic accidents and ensuring the efficient operation of traffic signals. Improving traffic safety is of paramount importance, as road accidents claim over a million lives annually worldwide, with a significant proportion of these fatalities occurring in developing countries like Bangladesh. This research aims to develop a smart assistant capable of identifying and categorizing traffic signs to enhance road safety, especially in areas where drivers may not be fully aware of traffic regulations. To achieve this, we generated a comprehensive dataset containing 5,540 distinct images of traffic signs collected from various regions across Bangladesh, including highways, rural and urban roads, and challenging locations such as steep curves. The dataset comprises 41 categories of traffic signs. The dataset includes challenges such as color variations, blurriness, occlusion, small sign sizes, and low-light conditions. To further enhance the dataset's diversity, data augmentation techniques such as random rotations, shearing, and zooming were applied. We trained the YOLOv8 deep learning model, renowned for its real-time object detection capabilities, on this dataset. The model achieved impressive results, with a mean Average Precision (mAP) of 0.80, a recall of 0.87, a precision of 0.92, and an F1 score of 0.89, demonstrating its effectiveness in real-world traffic sign detection and classification.

The fifth-generation (5G) ultra-dense cellular networks may face redundant handover problems due to the small coverage areas of small cells and the mobility of users, which leads to significant packet losses and network delays.Therefore, the overall user experience may degrade.In this paper, we propose a user clustering-based handover mitigation algorithm to improve the user experience for fast-moving users.To that end, the algorithm detects fast-moving users and finds their locations.Therefore, fast-moving user groups are formed by applying a clustering technique, where a central user becomes a small cell to serve the remaining users in each cluster.Simulation results demonstrate that the approach can mitigate 96.76% redundant handovers and maintain an average network throughput of 100 Mbps.

Ensuring the robust performance of avionics systems demands meticulous attention to worst-case execution time (WCET) analysis. This is especially important in multicore environments where execution time can vary widely. This paper examines the interplay between data flow and control flow analysis within the context of avionics multicore systems, proposing a comprehensive solution for efficient WCET estimation. Drawing from industry standards such as A(M)C 20–193 [2] [3] and DO-178C/ED-12C [1], our approach emphasizes the integration of data flow and control flow analysis to accurately assess task execution times, thereby enhancing system reliability and safety. Additionally, this paper includes calculations of WCET using two different combinations of hardware and real time operating systems (RTOS) to illustrate the importance of considering the different characteristics of an environment in measuring this crucial timing.

In this paper, we have analyzed the impact of improper implementation of Transport Layer Security (TLS) in Android applications. Communication security in Android applications is largely dependent on Transport Layer Security. For instance, data encryption, data integrity, authentication, trust-building, network attack prevention, and API and web service security are all provided by it. TLS preserves confidence and aids in preventing the unwanted exposure of sensitive data. However, improper implementation of TLS can pose a serious threat to the cybersecurity of an application. Therefore, software developers should ensure the security of applications, foster client confidence, and adhere to legal standards by skillfully implementing TLS. In this paper, we have chosen 25 miscellaneous Android applications and performed static analysis on them. Furthermore, we have identified various improper implementations of TLS in these applications. The riskiest TLS implementations in these applications include insufficient verification of the TLS certificate chain, invalid TLS certificates, insufficient checking of the TLS certificate validity, and insecure WebViews usage. For these vulnerable implementations of TLS, some applications are prone to a man-in-the-middle (MitM) attack. At last, we have provided the best practices of TLS implementations for Android applications. In addition, we have provided remediation for the vulnerabilities so that applications can be protected against MitM attacks.

In this work, initially a rectangular microstrip patch antenna measuring (94.8 × 110 × 10) µm3 with a polyamide substrate has been analyzed and developed. The antenna has a bandwidth of 170 GHz (1.98 - 2.15 THz) and is tuned to resonate at a frequency of 2.08 THz. Its return loss is -26.733 dB, radiation efficiency is 92<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">%</sup>, and maximum gain is 6.35 dB. In addition, the MIMO technology has been implemented to improve performance. Its bandwidth is 210 GHz (1.98-2.19 THz), and it offers a reflection coefficient of -37.75 dB, a radiation efficiency of 95%, and a peak gain of 6.01 dB. The substrate of the four-element MIMO antenna measures (154.8<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sup>170<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sup>10) µm3. The HFSS platform has been used to perform the modelling and simulation.

This study illustrates the most recent developments and evolution of solvent extraction techniques for metal ion separation. It emphasizes the replacement of conventional extractants, such as TBP and β-diketones, with modern ones, including LIX reagents, D2EHPA, TOPO, and Cyanex reagents, as a result of enhanced design and process optimization. Recent research has demonstrated the efficacy of novel extractants in selectively targeting metal ions from complex matrices, illustrating the continuous advancements in solvent extraction techniques. In hydrometallurgy, solvent extraction is essential for the recovery, purification, and separation of both high-value and low-value metals. The review examines the history, principles, and applications of solvent extraction, with a particular emphasis on the mechanism of metal ion transfer and the characteristics of extractants such as Cyanex 272. It includes research on Mn(II) and Ni(II), as well as extractants' physicochemical properties and efficacy in selective separations. Additionally, it addresses extraction kinetics. The research also investigates surfactant properties, ligand exchange processes, and interfacial phenomena, all of which contribute to the development of environmentally benign metal extraction methods. Furthermore, it analyzes the commercial and selective separation value of extractants such as Cyanex 272, the limitations of traditional methods, the necessity for inventive alternatives, as well as historical innovations. The versatility and ongoing significance of solvent extraction in hydrometallurgical technology are underscored by mechanistic studies, which improve our comprehension of the stability constants and extraction behaviors of Mn(II) and Ni(II).

In this study, a photovoltaic (PV) device has been developed by using AgBiS2 as the key material. The simulation of the photovoltaic cell has been performed using the SCAPS-1D simulator to analyze the impact of each layer. The design incorporates three window layers, CdS, In2S3, and ZnSe, alongside six familiar compounds, AlSb, CuGaSe2 (CGS), CuS, MoS2, Sb2S3, and WSe2, as the back surface field (BSF) layers. These heterostructures aim to uncover the potential of AgBiS2 in the realm of photovoltaic technology. When AgBiS2 functions within a singular heterojunction, specifically in configurations such as n-CdS/p-AgBiS2, n-In2S3/p-AgBiS2, and n-ZnSe/p-AgBiS2, the resulting values for open-circuit voltage (V OC) and the short circuit current (J SC) are found to be ∼0.90 V and ∼32 mA/cm2, respectively, while the corresponding power conversion efficiencies (PCE) are 23.56%, 22.60%, and 23.62%, respectively. On the contrary, the incorporation of various BSF layers like AlSb, CGS, CuS, MoS2, Sb2S3, and WSe2 results in a substantial increase in V OC, leading to an enhancement in PCE. Among the AgBiS2 based different dual-heterostructures, the outstanding PCE of 30.04% with a V OC of 1.12 V is achieved by n-ZnSe/p-AgBiS2/p+-Sb2S3 device. In comparison, the n-ZnSe/p-AgBiS2/p+-CGS structure exhibits a similar PCE of 30.03% with a V OC of 1.12 V. Additionally, the n-ZnSe/p-AgBiS2/p+-MoS2 arrangement demonstrates a PCE of 29.95% and a V OC of 1.12 V. The effective band alignments observed at the interfaces of ZnSe/AgBiS2 and AgBiS2/MoS2, ZnSe/AgBiS2 and AgBiS2/CGS, as well as ZnSe/AgBiS2 and AgBiS2/Sb2S3 contribute to a substantial built-in potential, leading to an elevated V OC. As an alternative to ZnSe, the CdS window could offer similar performances, whereas In2S3 might provide a lower efficiency. The elaborate simulation findings highlight the substantial potential of AgBiS2 as an absorber, particularly when coupled with different windows and BSF layers. This opens avenues for experimental research focused on AgBiS2 in the era of photovoltaic cells.

The phrase "Cross Linguistics," also known as "Translanguaging" in a broader sense, serves as the basis for this research’s core point of discussion. It is needless to describe the importance of the English language in Bangladesh, where it has gained the status of a second official language. The paper intends to unfold every possible kind of influence on Bangladeshi English Language Learners having different dialects while learning it as a Foreign Language. Researchers have surveyed around 45 tertiary-level language learners from some prominent universities in Bangladesh. Both qualitative and quantitative data collection methods have been followed, along with tools like interviews and surveys, on the selected samples for this research. The outcome of this research endeavor is expected to provide us with a clear focus on both the positive and negative effects of using cross-dialectal forms by English Language Learners.