William Liu

William Liu
Auckland University of Technology | AUT · Information Technology and Software Engineering, School of Engineering, Computer and Mathematical Sciences

PhD, ECE at the University of Canterbury

About

104
Publications
22,701
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896
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Introduction
William Liu is currently a Senior Lecturer in the Department of Information Technology and Software Engineering, School of Engineering, Computer and Mathematical Sciences at the Auckland University of Technology, New Zealand. He holds a Masters degree and a PhD degree in Electrical and Computer Engineering, both obtained at the University of Canterbury, New Zealand. He had been working as a network planner and designer in Beijing Telecom for 5 years before he immigrated to New Zealand. He has co-authored more than 75 papers published in international journals and conferences, and he participates in the Program Committees of several premier IEEE conferences including GLOBECOM, INFOCOM, ICC, GreenCom, CloudNet, DRCN, RNDM and ATNAC.
Additional affiliations
July 2015 - September 2017
Auckland University of Technology
Position
  • Lecturer
July 2015 - September 2017
Auckland University of Technology
Position
  • Lecturer
July 2010 - present
Auckland University of Technology
Position
  • Senior Lecturer and Academic Leader for MCIS/PGDip CIS/PGCert CIS/BCIS(Hons)
Description
  • William's research interest is in the design and performance evaluation of infrastructures and protocols for packet-oriented networks. He is working especially in the area of network survivability, sustainability and trustworthy computing.

Publications

Publications (104)
Article
Full-text available
Smart cities use many smart devices to facilitate the well-being of society by different means. However, these smart devices create great challenges, such as energy consumption and carbon emissions. The proposed research lies in communication technologies to deal with big data-driven applications. Aiming at multiple sources of big data in a smart c...
Article
Full-text available
In a smart city, a large number of smart sensors are operating and creating a large amount of data for a large number of applications. Collecting data from these sensors poses some challenges, such as the connectivity of the sensors to the data center through the communication network, which in turn requires expensive infrastructure. The delay-tole...
Research Proposal
Full-text available
https://www.frontiersin.org/research-topics/16899/bridging-global-broadband-divides-concepts-understanding-and-network-solutions
Article
Full-text available
The Internet of Things (IoT) refers to an emerging paradigm to seamlessly and ubiquitously integrate a large number of smart things with intra/inter links to the physical and cyber worlds. Sensor-enabled communication technologies connect billions of things by efficiently utilizing their locations in the real world. This has fostered active partici...
Article
Full-text available
In recent years, there has been a big data revolution in smart cities dues to multiple disciplines such as smart healthcare, smart transportation, and smart community. However, most services in these areas of smart cities have become data-driven, thus generating big data that require sharing, storing, processing, and analysis, which ultimately cons...
Article
Currently, there is a very large volume of Covid-19 related medical data that have been stored in cloud based systems and made available for studing the disease dynamics. without any privacy-preservation. In order to reduce possible privacy leakage and also accommodate massive medical reports with high efficiencies, we proposed a privacy preserving...
Conference Paper
It is foreseeable the popularity of the mobile edge computing enabled infrastructure for wireless networks in the incoming fifth generation (5G) and future sixth generation (6G) wireless networks. Especially after a 'hard' disaster such as earthquakes or a 'soft' disaster such as COVID-19 pandemic, the existing telecommunication infrastructure, inc...
Article
Full-text available
Small Cells (SCs) mounted on top of Unmanned Aerial Vehicles (UAVs) can be used to boost the radio capacity in hotspot zones. However, UAV-SCs are subject to tight battery constraints, resulting in frequent recharges operated at the ground sites. To meet the UAV-SCs energy demanded to the ground sites, the operator leverages a set of Solar Panels (...
Article
Full-text available
Significant technological advancements over the last two decades have led to enhanced accessibility to computing devices and the Internet. Our society is experiencing an ever-growing integration of the Internet into everyday lives, and this has transformed the way we obtain and exchange information, communicate and interact with one another as well...
Article
Full-text available
One of the main challenges of operating a smart city (SC) is collecting the massive data generated from multiple data sources (DSs) and transmitting them to the control units (CUs) for further data processing and analysis. These ever-increasing data demands require not only more and more capacity of the transmission channels but also results in res...
Conference Paper
Reprogramming is a mechanism for software upgrade in the deployed devices. It is used to repair bugs in the running of the device or change the software function of the device according to the new requirements. Because the wireless body area network (WBAN) needs long-term operation, the software maintenance of the node is unavoidable. The tradition...
Poster
Full-text available
During and after disasters, rescue operations face a number of difficulties as the obstacles for effective and efficient operation. This research concentrates on resource allocation in regard to casualty. ❖ Most resource deployment strategies are generated manually by professional people associated with their experience (Muaafa, Concho and Ramirez-...
Chapter
The Internet has evolved as a critical booster for the economic, social and technical development of human society. Almost half of the world’s population is unfortunately missing out due to the lack of access to the Internet. Such users are mainly those living in rural and low-income areas. Various strategies and approaches for improving the Intern...
Chapter
Full-text available
The emerging smart city paradigm e.g., intelligent transport, smart grid and participatory sensing etc. is to advance the quality, performance and experience of urban citizten services through greater connectivity. This paradigm needs to collect data from citizens, various devices and assets that could be monitored, processed and analysed for the c...
Chapter
The emerging cyber-physical paradigm endeavours to unite all the physical objects embedded with electronics, software, sensors, and network connectivity to allow more direct interactions and information sharing between the physical and cyber worlds. While these massively connected devices and their associated communications can exponentially increa...
Chapter
The advancement in the field of information and communication technology has generated a great deal of information that was not possible to access earlier. Healthcare systems are one of the most beneficial applications using wireless medical sensor technologies, which can facilitate patient care within homes, hospitals, clinics, disaster sites, and...
Conference Paper
Full-text available
With the growing popularization of Electric Vehicles (EVs), charging management has become an increasingly important research problem in smart cities. Different from plug-in charging technology, we alternatively enable the battery switch technology to provide fast EV charging (reduce the service waiting time from tens of minutes to a few minutes),...
Chapter
Full-text available
The advancement in the field of information and communication technology has generated a great deal of information that was not possible to access earlier. Healthcare systems are one of the most beneficial applications using wireless medical sensor technologies, which can facilitate patient care within homes, hospitals, clinics, disaster sites, and...
Conference Paper
The Internet has evolved as a critical booster for the economic, social and technical development of human society. Almost half of the world's population is unfortunately missing out due to the lack of access to the Internet. Such users are mainly those living in rural and low-income areas. Various strategies and approaches for improving the Intern...
Conference Paper
Full-text available
The digital divide refers to the gap between those who have access to modern information and communications technology (ICT) and those who do not or who have constrained access. This technology could include telephones, television, computers and the Internet. The arrival of high-speed Internet connectivity to the Kingdom of Tonga continues to bring...
Article
In September 2015, the United Nations General Assembly accepted the 2030 Development Agenda, which has included 92 paragraphs, and the Paragraph 91 defined 17 sustainable development goals (SDGs) and 169 associated targets. The goal of this paper is to discover the correlations among SDGs and information and communications technologies (ICTs). This...
Conference Paper
Full-text available
The New Zealand Government has set the goals of having 99% of Kiwis able to access broadband with peak speeds of at least 50 Megabits per second (Mbps) by 2025, and with the remaining 1% able to access broadband with rates of at least 10 Mbps. There is an interesting question to be raised: is it possible to achieve these goals earlier? Inspired by...
Conference Paper
Full-text available
We propose a business model to compute the monthly subscription fee for users served by an innovative 5G network architecture that is designed to serve rural zones. We consider two possible options to deploy the 5G cells. In the first case, the connectivity is provided by means of small cells mounted on top of Unmanned Aerial Vehicles (UAVs). In th...
Conference Paper
Full-text available
The traditional world has transformed into a digital society where almost anything can be accessed from anywhere. However, this digital society is responsible for an explosive growth of high-volume, high-velocity and high-variety information assets, with high demand for "Big Data". A Software Defined Connectivity (SDC) is an emerging paradigm, whic...
Chapter
In this chapter we firstly review the state of the art of the data center networks (DCNs) topological structures and explain the challenges in this field, which motivates our work. Then we propose a method for evaluating the topological metrics related to network robustness and node centrality so as to identify the most critical nodes and links in...
Article
Full-text available
Nowadays, at least two billion people are experiencing a complete lack of wireless cellular network coverage. These users live in rural areas and low-income regions, where network operators are not keen to invest, mainly due to high Capital Expenditure (CapEx) and Operational Expenditure (OpEx) costs, as well as the scarcity of electricity from the...
Conference Paper
Immediately after a disaster, the normal telecom-munication infrastructure, including wired and wireless networks , is often seriously compromised and cannot guarantee regular coverage and reliable communications services. These temporarily-missing communications capabilities are crucial to rescuers and affected citizens as the responders need to e...
Conference Paper
Full-text available
Challenged Networks (CNs) are characterized by frequent varying network conditions and intermittent connectivity. In general, CNs emerge in different scenarios including the disaster and emergency situations when the traditional cellular infrastructure is dysfunctional or unavailable as well as in the undeserved areas such as rural and developing r...
Conference Paper
The advancements of Information and Communications Technologies (ICT) have contributed to an explosive growth of high-volume, high-velocity and high-variety information assets, and the era of Big Data has emerged. The infrastructure-based networks are becoming increasingly overloaded, while the cost of maintaining and expanding the infrastructure t...
Article
Full-text available
We propose a framework to manage the link lifetime in an IP backbone network by exploiting the Sleep Mode (SM). In particular, when a SM feature is available, two different effects coexist: i) during the SM state, the lifetime tends to be increased; however, ii) when the link changes its power state (from SM to full power or vice-versa), the lifeti...
Conference Paper
Full-text available
Current trends in telecommunication networks foresee the adoption of the fifth generation (5G) of wireless networks in the near future. However, a large number of people are living without coverage and connectivity. To face this issue, we consider the possibility of deploying 5G networks in rural and low-income zones. After detailing the current st...
Article
IEEE 802.11n networks are widely used in home and corporate network environments because they offer high-speed wireless Internet access at relatively low-cost. The 802.11n standard introduced several key features including Block acknowledgement (ACK) and reverse direction (RD) data transmission for enhanced system performance. An in-depth study of...
Article
Full-text available
We present a model to evaluate the server lifetime in cloud data centers (DCs). In particular, when the server power level is decreased, the failure rate tends to be reduced as a consequence of the limited number of components powered on. However, the variation between the different power states triggers a failure rate increase. We therefore consid...
Article
Full-text available
The security issues in wireless sensor networks (WSNs) are crucial and the limitation of computing resources and distributed properties of WSN make the traditional security mechanisms no longer feasible in protecting WSN as in the wired networks. There is an emerging research area i.e., trust and reputation mechanisms, has been developed, as an alt...
Research
Proceedings of the third IEEE Global Conference on Signal & Information Processing, Orlando, USA, December, 2015
Article
Smart grid is the trend of next generation electrical power system which has integrated the information and communication technologies and enables the existing power grid to perform more intelligent and efficient operations. A high level of network availability is therefore required to guarantee two-way flows of electricity and information among el...
Chapter
Smart Grid is the next generation of the electrical power systems that form from interdependent networks. Cascading failures in such interdependent critical infrastructure is very crucial which can cause wide spread disruption. This chapter is intended to evaluate four different topological metrics in which can be best described and approximated th...
Conference Paper
The autonomous features of wireless sensor network (WSN) and the rapid deployment of smart metering devices have revolutionized the smart grid infrastructures. These developments have driven the WSN-based smart metres for automatic recording, processing and evaluating energy information, and managing efficient energy usage. The smart metres are not...
Conference Paper
Full-text available
Security issues for Wireless sensor network (WSN) is always crucial due to its nature. The limitation of computing resources and distributed properties in WSN makes the traditional security mechanisms no longer as feasible in protecting WSN as in wired networks. There is an emerging research area to discover the alternative solutions on trust and r...
Chapter
Full-text available
Smart Grid is believed to be the next generation of electrical power system. It integrates the existing electrical power infrastructure with information communications technology (ICT) to achieve two way communication and become smart. A high level of network availability is therefore required to guarantee two-way flows of electricity and informati...
Conference Paper
Full-text available
Network lifetime is one of the key characteristics for evaluating wireless sensor networks (WSNs) in an application-specific way based on the availability of sensor nodes, wireless radio coverage, and wireless connectivity. Basically it shows in a resource constrained environment the consumption of every limited resource must be considered. A large...
Conference Paper
Vehicular communication networks such as vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) are a type of network in which vehicles and roadside units are the communicating nodes, providing each other with information such as safety warnings and traffic information. As a cooperative approach, vehicular communications can be more effective...
Article
Understanding the correlation between the underlie network structure and overlay cascade effects in the interdependent networks is one of major challenges in complex network studies. There are some existing metrics that can be used to measure the cascades. However, different metrics such as average node degree interpret different characteristic of...
Article
Full-text available
The wireless sensor-cloud networks (WSCNs) are becoming popular nowadays. The new concept of trust has emerged in recent studies as an alternative mechanism to address the security concern in WSCN. Most of the studies on trust are focusing on how to model and evaluate trust so as to effectively detect any malicious activity in the network and then...