Massey Documents by Type
Permanent URI for this communityhttps://mro.massey.ac.nz/handle/10179/294
Browse
4 results
Search Results
Item Placement optimization of multiple UAVs for energy-efficient maximal user coverage(Elsevier B.V., 2025-10-09) Zhang C; Gui X; Gupta GS; Hasan SFThis paper proposes a deterministic Global Optimization Algorithm (GOA) for UAV-assisted communications, developed as an enhancement to the benchmark Two-Stage Optimization Algorithm (TSOA). The algorithm simultaneously addresses the dual objectives of maximizing ground user (GU) coverage and minimizing total power consumption in multiple UAV systems. Unlike existing literature, which predominantly relies on heuristic approaches, GOA provides a more precise and systematic solution to achieve optimal performance. Comprehensive simulations demonstrate that GOA achieves a 3.68 % increase in coverage count versus SOA under clustered GU distributions while delivering energy savings approximately 2.47 % (uniform) and 2.6 % (clustered) relative to the TSOA benchmark. Crucially, these efficiency gains are realized while maintaining superior GU coverage maximization versus all benchmarked methods. Both numerical results and visual analyses conclusively validate the proposed algorithm's outperformance of existing benchmarks. ©2025 The Korean Institute of Communications and Information Sciences. Publishing Services by Elsevier B.V. This is an open access article under the CC BY-NCND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Item A review of semantic segmentation methods and their application in apple disease detection(Elsevier B.V., 2025-05-26) Keshavarzi M; Mesarich C; Bailey D; Johnson M; Gupta GSSemantic segmentation, with pixel-wise classification, enables the precise identification of different parts of plants, as well as the diseases that occur on them, in agricultural images. Apples, as one of the most important fruit crops worldwide, are susceptible to various diseases, causing decreased crop quality and increased crop loss. To prevent disease progression and ensure prompt treatment, semantic segmentation acts as an effective method in the context of apple disease detection. This review provides a comprehensive analysis of semantic segmentation methods applied in apple disease detection, ranging from traditional approaches to state-of-the-art techniques. By systematically examining the entire pipeline, from dataset preparation to the segmentation and evaluation stages, this work not only synthesises existing knowledge but also reviews applied solutions and highlights remaining research gaps to enhance segmentation performance. Additionally, it offers a forward-looking perspective by proposing future research directions. Overall, this review aims to advance plant disease detection through semantic segmentation, with a particular emphasis on apples.Item Visible Light Positioning-Based Robot Localization and Navigation(MDPI (Basel, Switzerland), 2024-01-01) Chew M-T; Alam F; Noble FK; Legg M; Gupta GS; Pak JMVisible light positioning or VLP has been identified as a promising technique for accurate indoor localization utilizing pre-existing lighting infrastructure. Robot navigation is one of the many potential applications of VLP. Recent literature shows a small number of works on robots being controlled by fusing location information acquired via VLP that uses a rolling shutter effect camera as a receiver with other sensor data. This paper, in contrast, reports on the experimental performance of a cartesian robot that was controlled solely by a VLP system using a cheap photodiode-based receiver rigidly attached to the robot’s end-effector. The receiver’s position was computed using an inverse-Lambertian function for ranging followed by multi-lateration. We developed two novel methods to leverage the VLP as an online navigation system to control the robot. The position acquired from the VLP was used by the algorithms to determine the direction the robot needed to move. The developed algorithms guided the end-effector to move from a starting point to target/destination point(s) in a discrete manner, determined by a pre-determined step size. Our experiments consisted of the robot autonomously repeating straight line-, square- and butterfly-shaped paths multiple times. The results show median errors of 27.16 mm and 26.05 mm and 90 percentile errors of 37.04 mm and 47.48 mm, respectively, for the two methods.Item Network Lifetime Improvement through Energy-Efficient Hybrid Routing Protocol for IoT Applications(MDPI (Basel, Switzerland), 2021-11-09) Mishra M; Gupta GS; Gui X; Takefuji Y; Mukhopadhyay S; Vezzetti EThe application of the Internet of Things (IoT) in wireless sensor networks (WSNs) poses serious challenges in preserving network longevity since the IoT necessitates a considerable amount of energy usage for sensing, processing, and data communication. As a result, there are several conventional algorithms that aim to enhance the performance of WSN networks by incorporating various optimization strategies. These algorithms primarily focus on the network layer by developing routing protocols to perform reliable communication in an energy-efficient manner, thus leading to an enhanced network life. For increasing the network lifetime in WSNs, clustering has been widely accepted as an important method that groups sensor nodes (SNs) into clusters. Additionally, numerous researchers have been focusing on devising various methods to increase the network lifetime. The prime factor that helps to maximize the network lifetime is the minimization of energy consumption. The authors of this paper propose a multi-objective optimization approach. It selects the optimal route for transmitting packets from source to sink or the base station (BS). The proposed model employs a two-step approach. The first step employs a trust model to select the cluster heads (CHs) that manage the data communication between the BS and nodes in the cluster. Further, a novel hybrid algorithm, combining a particle swarm optimization (PSO) algorithm and a genetic algorithm (GA), is proposed to determine the routes for data transmission. To validate the efficacy of the proposed hybrid algorithm, named PSOGA, simulations were conducted and the results were compared with the existing LEACH method and PSO, with a random route selection for five different cases. The obtained results establish the efficiency of the proposed approach, as it outperforms existing methods with increased energy efficiency, increased network throughput, high packet delivery rate, and high residual energy throughout the entire iterations.
