Search

Based on 14 naturally corroded full-scale pipe specimens, the present study investigates to what extent a corrosion depth threshold influences the burst capacity of naturally corroded pipelines predicted using the finite element analysis (FEA) and well-known RSTRENG model. The study also employs FEA and RSTRENG to investigate the accuracy and effectiveness of five representative interaction rules, namely the B31G, B31.4, CSA, DNV and CW rules, for combining individual naturally-occurring corrosion anomalies into clusters. The analysis results indicate that applying a corrosion depth threshold of 10% of the pipe wall thickness (t) (i.e. any corrosion depths < 10%t are ignored) has a negligible impact on the predicted burst capacity. Furthermore, the CSA interaction rule is considered the most effective among the five interaction rules investigated in that it captures the most critical region of a corroded area without resulting in very large corrosion clusters that are time-consuming to identify and analyze.

Abstract Considering the insufficient global energy consumption optimization of the existing routing algorithms for Underwater Wireless Sensor Network (UWSN), a new algorithm, named improved energy-balanced routing (IEBR), is designed in this paper for UWSN. The algorithm includes two stages: routing establishment and data transmission. During the first stage, a mathematical model is constructed for transmission distance to find the neighbors at the optimal distances and the underwater network links are established. In addition, IEBR will select relays based on the depth of the neighbors, minimize the hops in a link based on the depth threshold, and solve the problem of data transmission loop. During the second stage, the links built in the first stage are dynamically changed based on the energy level (EL) differences between the neighboring nodes in the links, so as to achieve energy balance of the entire network and extend the network lifetime significantly. Simulation results show that compared with other typical energy-balanced routing algorithms, IEBR presents superior performance in network lifetime, transmission loss, and data throughput.

Performance enhancement of Underwater Wireless Sensor Networks (UWSNs) in terms of throughput maximization, energy conservation and Bit Error Rate (BER) minimization is a potential research area. However, limited available bandwidth, high propagation delay, highly dynamic network topology, and high error probability leads to performance degradation in these networks. In this regard, many cooperative communication protocols have been developed that either investigate the physical layer or the Medium Access Control (MAC) layer, however, the network layer is still unexplored. More specifically, cooperative routing has not yet been jointly considered with sink mobility. Therefore, this paper aims to enhance the network reliability and efficiency via dominating set based cooperative routing and sink mobility. The proposed work is validated via simulations which show relatively improved performance of our proposed work in terms the selected performance metrics.

Performance enhancement of Underwater Wireless Sensor Networks (UWSNs) in terms of throughput maximization, energy conservation and Bit Error Rate (BER) minimization is a potential research area. However, limited available bandwidth, high propagation delay, highly dynamic network topology, and high error probability leads to performance degradation in these networks. In this regard, many cooperative communication protocols have been developed that either investigate the physical layer or the Medium Access Control (MAC) layer, however, the network layer is still unexplored. More specifically, cooperative routing has not yet been jointly considered with sink mobility. Therefore, this paper aims to enhance the network reliability and efficiency via dominating set based cooperative routing and sink mobility. The proposed work is validated via simulations which show relatively improved performance of our proposed work in terms the selected performance metrics. [ABSTRACT FROM AUTHOR]

Underwater Wireless Sensor Networks (UWSNs) support various applications like pollution monitoring, tsunami warnings, offshore exploration, tactical surveillance, etc. Distinctive features of UWSNs like low available bandwidth, large propagation delay, highly dynamic network topology, and high error probability pose many challenges for designing efficient and reliable communication protocols. In this paper, we propose an extension of IAMCTD (Improved Adaptive Mobility of Courier nodes in Threshold-optimized DBR protocol for UWSNs) that focuses on enhancing network reliability and throughput for critical-range based applications. Our scheme avoids control overhead that was present in IAMCTD for implementing changes in depth threshold. The movement pattern of courier nodes along with reducing communication burden on nodes increases throughput as well. Additionally, stability period is improved and node density per round remains comparatively high improving the overall network reliability. Based on the comprehensive simulations using MATLAB, we observe that our scheme improves the performance in terms of throughput and stability period. Moreover, comparatively higher network density per round is maintained and end-to-end delay is stabilized throughout the network lifetime. [ABSTRACT FROM AUTHOR]