Integrated multiple-sensor methodology for condition assessment of water mains

Considerable capital investment has been made in civil infrastructure systems across the globe including water mains. Currently, existing failure detection and location methods do not allow for quick reaction to failures. In addition, no unified standards are followed in condition assessment of water mains. Moreover, the decision by which water mains are inspected is currently carried out based on approximation and experience of decision-makers, which might be limited and may lead to overlooking suitable evaluation methods that might save time, effort and cost. This research presents a methodology that contributes to different phases in the asset management of water mains. It enhances current practice in condition assessment of water mains and assists in setting up rehabilitation priorities. The methodology implemented is based on intensive literature review, evaluation of current methods, field investigation and experiments, and interviews with experts. The methodology considered augments two approaches currently used in condition assessment of water mains, which are proactive and reactive methods. The developed methodology calls for designing a new decision support system (DSS) for selection of most suitable non-destructive evaluation (NDE) method(s). It consists of two components: 1) A Database management system (DBMS), and 2) an evaluation and ranking module (ERM). These NDE methods are used for either detecting suspected leaks or measuring pipe wall thickness, the latter is employed to predict remaining service life of pipe being considered. In case of suspected leaks, this study presents a newly designed automated system for detection of water leaks in underground pipelines and identifying their respective locations. The development of this system is based on using Thermography infrared (IR) camera in order to detect thermal contrast at the pavement surface due to water leaks at the most suitable time. The data obtained is analyzed in order to establish the relationship between the detected leakage area and the approximate location of leak. Prototype software developed in Visual C# environment is implemented in order to determine the location of leaks automatically. Two deterioration models were designed and developed for estimating remaining useful life of water mains, and predicting annual breakage rate of water mains. The development of the two models is based on the analysis of real data collected from 16 municipalities in Canada and the US. The two models were developed considering two approaches, multiple regression analysis and Artificial Neural Networks (ANNs) based on the most suitable subsets of selected factors. The final model was selected due to its reliability and better performance in comparison to other models. The outputs of the deterioration models developed in this research were used, in addition to other deterioration factors that were not considered in existing models in order to develop a Decision Support System (DSS) for generating condition rating scale of water main being considered, and for prioritizing rehabilitation/ maintenance actions. The system is hierarchal in structure, and the condition-rating index is generated using Multi Attributes Utility Theory (MAUT). System validation was carried out by comparing its outcome with real case studies. A prototype software application of the model presented in this research is implemented as a proof of concept to demonstrate the capabilities and essential features of the developed models

Natural and Technological Hazards in Urban Areas

Natural hazard events and technological accidents are separate causes of environmental impacts. Natural hazards are physical phenomena active in geological times, whereas technological hazards result from actions or facilities created by humans. In our time, combined natural and man-made hazards have been induced. Overpopulation and urban development in areas prone to natural hazards increase the impact of natural disasters worldwide. Additionally, urban areas are frequently characterized by intense industrial activity and rapid, poorly planned growth that threatens the environment and degrades the quality of life. Therefore, proper urban planning is crucial to minimize fatalities and reduce the environmental and economic impacts that accompany both natural and technological hazardous events

Cumulative index to NASA Tech Briefs, 1986-1990, volumes 10-14

Tech Briefs are short announcements of new technology derived from the R&D activities of the National Aeronautics and Space Administration. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This cumulative index of Tech Briefs contains abstracts and four indexes (subject, personal author, originating center, and Tech Brief number) and covers the period 1986 to 1990. The abstract section is organized by the following subject categories: electronic components and circuits, electronic systems, physical sciences, materials, computer programs, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences

25 years of network access technologies: from voice to internet; the changing face of telecommunications

This work contributes to knowledge in the field of semiconductor system architectures, circuit design and implementation, and communications protocols. The work starts by describing the challenges of interfacing legacy analogue subscriber loops to an electronic circuit contained within the Central Office (Telephone Exchange) building. It then moves on to describe the globalisation of the telecom network, the demand for software programmable devices to enable system customisation cost effectively, and the creation of circuit and system blocks to realise this. The work culminates in the application challenges of developing a wireless RF front end, including antenna, for an Ultra Wideband communications systems applications. This thesis illustrates how higher levels of integration over the period of 1981 to 2010 have influenced the realisation of complex system level products, particularly analogue signal processing capabilities for communications applications. There have been many publications illustrating the impact of technology advancement from an economic or technology perspective. The thesis shows how technology advancement has impacted the physical realisation of semiconductor products over the period, at system, circuit, and physical implementation levels

Unmanned Vehicle Systems & Operations on Air, Sea, Land

Unmanned Vehicle Systems & Operations On Air, Sea, Land is our fourth textbook in a series covering the world of Unmanned Aircraft Systems (UAS) and Counter Unmanned Aircraft Systems (CUAS). (Nichols R. K., 2018) (Nichols R. K., et al., 2019) (Nichols R. , et al., 2020)The authors have expanded their purview beyond UAS / CUAS systems. Our title shows our concern for growth and unique cyber security unmanned vehicle technology and operations for unmanned vehicles in all theaters: Air, Sea and Land – especially maritime cybersecurity and China proliferation issues. Topics include: Information Advances, Remote ID, and Extreme Persistence ISR; Unmanned Aerial Vehicles & How They Can Augment Mesonet Weather Tower Data Collection; Tour de Drones for the Discerning Palate; Underwater Autonomous Navigation & other UUV Advances; Autonomous Maritime Asymmetric Systems; UUV Integrated Autonomous Missions & Drone Management; Principles of Naval Architecture Applied to UUV’s; Unmanned Logistics Operating Safely and Efficiently Across Multiple Domains; Chinese Advances in Stealth UAV Penetration Path Planning in Combat Environment; UAS, the Fourth Amendment and Privacy; UV & Disinformation / Misinformation Channels; Chinese UAS Proliferation along New Silk Road Sea / Land Routes; Automaton, AI, Law, Ethics, Crossing the Machine – Human Barrier and Maritime Cybersecurity.Unmanned Vehicle Systems are an integral part of the US national critical infrastructure The authors have endeavored to bring a breadth and quality of information to the reader that is unparalleled in the unclassified sphere. Unmanned Vehicle (UV) Systems & Operations On Air, Sea, Land discusses state-of-the-art technology / issues facing U.S. UV system researchers / designers / manufacturers / testers. We trust our newest look at Unmanned Vehicles in Air, Sea, and Land will enrich our students and readers understanding of the purview of this wonderful technology we call UV.https://newprairiepress.org/ebooks/1035/thumbnail.jp

EFFICIENT DYNAMIC ADDRESSING BASED ROUTING FOR UNDERWATER WIRELESS SENSOR NETWORKS

This thesis presents a study about the problem of data gathering in the inhospitable underwater environment. Besides long propagation delays and high error probability, continuous node movement also makes it difficult to manage the routing information during the process of data forwarding. In order to overcome the problem of large propagation delays and unreliable link quality, many algorithms have been proposed and some of them provide good solutions for these issues, yet continuous node movements still need attention. Considering the node mobility as a challenging task, a distributed routing scheme called Hop-by-Hop Dynamic Addressing Based (H2- DAB) routing protocol is proposed where every node in the network will be assigned a routable address quickly and efficiently without any explicit configuration or any dimensional location information. According to our best knowledge, H2-DAB is first addressing based routing approach for underwater wireless sensor networks (UWSNs) and not only has it helped to choose the routing path faster but also efficiently enables a recovery procedure in case of smooth forwarding failure. The proposed scheme provides an option where nodes is able to communicate without any centralized infrastructure, and a mechanism furthermore is available where nodes can come and leave the network without having any serious effect on the rest of the network. Moreover, another serious issue in UWSNs is that acoustic links are subject to high transmission power with high channel impairments that result in higher error rates and temporary path losses, which accordingly restrict the efficiency of these networks. The limited resources have made it difficult to design a protocol which is capable of maximizing the reliability of these networks. For this purpose, a Two-Hop Acknowledgement (2H-ACK) reliability model where two copies of the same data packet are maintained in the network without extra burden on the available resources is proposed. Simulation results show that H2-DAB can easily manage during the quick routing changes where node movements are very frequent yet it requires little or no overhead to efficiently complete its tasks

Tunnel Engineering

This volume presents a selection of chapters covering a wide range of tunneling engineering topics. The scope was to present reviews of established methods and new approaches in construction practice and in digital technology tools like building information modeling. The book is divided in four sections dealing with geological aspects of tunneling, analysis and design, new challenges in tunnel construction, and tunneling in the digital era. Topics from site investigation and rock mass failure mechanisms, analysis and design approaches, and innovations in tunnel construction through digital tools are covered in 10 chapters. The references provided will be useful for further reading