Current Issue : October-December Volume : 2026 Issue Number : 4 Articles : 5 Articles
As the mainstream power system for unmanned aerial vehicles (UAVs), enhancing the performance of two-stroke engines is of paramount importance. This study developed a computational fluid dynamics (CFD) numerical model of the in-cylinder flow and combustion process in an opposed-piston two-stroke UAV engine. It focused on the influence patterns of rotational speed and injection timing on the engine’s combustion characteristics and power output. Research scenarios were set for typical rotational speed conditions (1000–3000 r/min) and injection timing conditions (BTDC 35–15 °CA). Results indicate that overall increasing engine speed while retarding the injection timing yields improved combustion efficiency and power output. At an engine speed of 2000 r/min, the ignition delay is reduced, and with an injection timing of −20 °CA, the engine shows a moderate process of combustion and heat release. Under these operating conditions, the combustion is characterized by a moderate heat release rate, relatively high cylinder pressure, enhanced indicated work and power, and comparatively low cylinder temperatures. Considering all performance aspects, employing an engine speed of 2000 r/min and an injection timing of −20 °CA yields superior combustion and power performance....
Sustainable transport management (STM) has become an increasingly important issue in recent years, as cities have faced growing traffic congestion, air pollution, and other transport-related challenges. Travel time (TT) represents one of the critical determinants of Quality of Service (QoS) and user satisfaction in public passenger transport (PPT). TT extends beyond in-vehicle duration and encompasses a sequence of temporal components, including access, waiting, transfer, and egress times. TT reflects the complexity of an integrated passenger transport system (IPTS), where users experience transport services as a door-to-door journey rather than isolated trips. This article analyses the TT within IPTSs through the lens of European quality standards EN 13816 and EN 15140 for PPT. Standard EN 13816 provides a normative framework for defining TT as a key QoS criterion reflecting user expectations and a user-oriented perspective, while standard EN 15140 operationalises this framework by specifying methodological requirements for the measurement and evaluation of the delivered TT quality at system-level performance objectives. This research highlights a structural gap between the conceptualisation of TT as a door-to-door journey, a user-oriented phenomenon, and its measurement through fragmented, mode-specific performance metrics. It limits the ability of transport authorities and operators to accurately evaluate the QoS and to design efficient urban mobility (UM) systems....
Intelligent Transportation System (ITS) interconnects smart technologies for the advancement in communication and autonomous decision making in vehicle interactions. It manages traffic control infrastructure, analyses road conditions, and supports cooperative awareness in a crucial environment. The sensors continuously collect real-time vehicle data, process it, and forward it to analysis servers to predict the behavior of Vehicular Ad hoc Networks (VANETs). Many approaches have been proposed to address research challenges in routing and improve communication for vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) systems. However, due to dynamic topology, the network becomes disturbed and loses established connections, leading to instability in data transmission against unpredictable behavior of the network.This research presents a framework, referred to as Energy Efficient Load Balanced Edge-Driven Vehicular Networks (EELB-EVN), that aims to attain load-balanced communication across vehicles and the interconnected infrastructure, thereby preventing congestion and reducing computational cost. In addition, an Intelligent offloading technique is developed using the Analytical Hierarchy Process (AHP) to reduce the additional overhead on the devices, thus enabling energy-aware and latency-sensitive vehicular communication. Furthermore, trustworthiness strategies are explored to enhance reliability and ensure the credibility of information. The simulation tests revealed the significance of the proposed framework compared to related schemes in terms of energy consumption and latency by 20% to 25%, task success rate and network throughput by 30% to 40%, and computational complexity by 33% across dynamic vehicular scenarios....
Food security and the stakeholders’ trust are essential to ensure that agricultural supply chains are transparent and secure. This research presents a Queueing-Assisted Blockchain Smart Contract (QABSC) framework to enhance end-to-end traceability in the millet supply chain. The framework incorporates fog computing into real-time data processing to reduce latency and optimizes transaction flow using queueing techniques, thereby ensuring an efficient and scalable blockchain supply chain platform. The Internet of Vehicles and Things (IoVT) connects cars, sensors, roadside infrastructure, and cloud and edge technologies to make transportation and mobility smarter. By integrating fog-layer intelligence with blockchain-based immutable record-keeping, Internet of Vehicles and Things enabled sensing and vehicular logistics, and end-to-end visibility, the proposed system may ensure tamper-resistant monitoring of millet products from farms to customers. Internet of Things (IoT) sensors collect real-time information about millet quality and storage conditions. This data is securely stored using the InterPlanetary File System (IPFS) and verified by smart contracts on a distributed ledger. This approach ensures automated compliance verification for auditors and regulators, immutable data storage, and conditional privacy. The proposed model reduces bottlenecks in blockchain transaction processing and enhances efficiency, privacy, data integrity, and trust among producers, distributors, retailers, farmers, and buyers. The proposed model is evaluated based on key performance metrics. The experimental evaluations of the proposed framework demonstrate enhanced throughput, improved transparency, reduced computational overhead, and robust security. This research focuses on a unique integration of smart contracts, queueing theory, IPFS, Fog Computing, IoT devices, and blockchain technology to promote sustainable and transparent millet supply chain management....
Enhanced traffic management and safety can be achieved using decentralised networks such as Vehicular Ad Hoc Networks (VANETs), which allow communication amongst vehicles. These networks support dynamic, real-time communications; however, they face difficulties in terms of scalability, security and network stability. Improved vision efficiency, cost reduction and enhanced connectivity in VANETs can be realised using multi-RSU and clustering methods, revealing real-world benefits. This research seeks to improve communication efficiency in VANETs by addressing issues such as network delay, power usage and communication cost. The goal is to improve network reliability in a dynamic vehicular setup with fixed Roadside Units (RSUs), ensuring constant connectivity and reduced overhead. Spectral Efficiency and Hybrid Multi-RSU Deployment with Cost Optimisation (SEHMR) approach introduces an innovative solution for improving vehicular communication. The system integrates clustering, scheduling and continuous cluster maintenance of vehicles. By analysing the initial population and probability values of vehicles, the Cost Optimisation (DEA) algorithm effectively optimises costs. RSUs are strategically positioned to improve coverage, communication and power efficiency. This approach is evaluated through extensive simulations using NS2 and the SUMO mobility suite, measuring performance through metrics such as efficiency, throughput, packet delivery ratio, data loss, end-to-end delay and overhead. The proposed SEHMR-VANET is compared with basic approaches such as HGAR-VANETS, ROOPVANET and ISFF-VANETs. Results indicate that SEHMR-VANET achieves higher energy efficiency and lower delay and data loss, revealing its effectiveness in improving traffic communication....
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