Lei Lei

Lei Lei
University of Guelph | UOGuelph · School of Engineering

Doctor of Philosophy

About

133
Publications
68,253
Reads
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6,262
Citations
Introduction
Lei Lei currently works in the School of Engineering, University of Guelph. Her current research interest mainly lies in applying the Artificial Intelligent and Machine Learning methodologies to the optimal control of Mobile Cloud Computing (MCC) and Internet-of- Things (IoT) based on the fifth generation (5G) wireless networks
Skills and Expertise

Publications

Publications (133)
Preprint
The Ambient Internet of Things (A-IoT) has emerged as a critical direction for achieving effective connectivity as the IoT system evolves to 6G. However, the introduction of A-IoT technologies, particularly involving backscatter modulation, poses numerous challenges for system design and network operations. This paper surveys current standardizatio...
Article
Full-text available
The Ambient Internet of Things (A-IoT) has emerged as a critical direction for achieving effective connectivity as the IoT system evolves to 6G. However, the introduction of A-IoT technologies, particularly involving backscatter modulation, poses numerous challenges for system design and network operations. This paper surveys current standardizatio...
Article
The vision of sixth-generation (6G) wireless networks paves the way for the seamless integration of digital twins into vehicular networks, giving rise to a Vehicular Digital Twin Network (VDTN). The large amount of computing resources as well as the massive amount of spatial-temporal data in Digital Twin (DT) domain can be utilized to enhance the c...
Article
In this article, we investigate the scheduling issue of diesel generators (DGs) in an Internet of Things (IoT)-Driven isolated microgrid (MG) by deep reinforcement learning (DRL). The renewable energy is fully exploited under the uncertainty of renewable generation and load demand. The DRL agent learns an optimal policy from history renewable and l...
Article
The Energy Router (ER) concept as a compact intelligent power electronic device has been proposed as the core of the Internet of Energy (IoE), maximizing energy efficiency, minimizing loss and costs, and addressing growing electricity demand. However, optimizing electricity routing in the residential sector has not been well investigated. Moreover,...
Preprint
Full-text available
In this paper, we investigate the scheduling issue of diesel generators (DGs) in an Internet of Things (IoT)-Driven isolated microgrid (MG) by deep reinforcement learning (DRL). The renewable energy is fully exploited under the uncertainty of renewable generation and load demand. The DRL agent learns an optimal policy from history renewable and loa...
Article
The Internet of Energy envisions the next generation of smart grids as a highly interconnected network, including advanced metering infrastructures, distributed energy resources, and bidirectional communication systems. The open architecture of IoE-based smart grid results in manifold security concerns, especially the risk of False Data Injection A...
Article
In Part I of this two-part paper (Multi-Timescale Control and Communications with Deep Reinforcement Learning—Part I: Communication-Aware Vehicle Control), we decomposed the multi-timescale control and communications (MTCC) problem in Cellular Vehicle-to-Everything (C-V2X) system into a communication-aware Deep Reinforcement Learning (DRL)-based pl...
Article
An intelligent decision-making system enabled by Vehicle-to-Everything (V2X) communications is essential to achieve safe and efficient autonomous driving (AD), where two types of decisions have to be made at different timescales, i.e., vehicle control and radio resource allocation (RRA) decisions. The interplay between RRA and vehicle control neces...
Article
Full-text available
Autonomous driving vehicles can reduce congestion and improve safety while increasing traffic efficiency. To reflect the quality of driving more comprehensively, the driving safety, efficiency and occupant comfort should be jointly optimized for autonomous vehicles. Furthermore, in order to cope with complicated traffic environments and achieve sat...
Article
High penetration of smart devices in IoE-enabled smart grids besides decentralization originated from employing renewable resources face the power system with intricate optimization problems. Operation scheduling of energy components is one of the principal problems that need to be addressed. However, engaging with big data produced by the intercon...
Preprint
Full-text available
Nowadays, the application of microgrids (MG) with renewable energy is becoming more and more extensive, which creates a strong need for dynamic energy management. In this paper, deep reinforcement learning (DRL) is applied to learn an optimal policy for making joint energy dispatch (ED) and unit commitment (UC) decisions in an isolated MG, with the...
Preprint
Full-text available
Decentralization and high penetration of smart devices in IoE-enabled smart grids face the power system with complex scheduling problems. Engaging with big data produced by the interconnected infrastructures, besides the high dimensional and uncertain environment, make traditional methods incapable of addressing these problems since exact modeling...
Preprint
Full-text available
Decentralization and high penetration of smart devices in IoE-enabled smart grids face the power system with complex scheduling problems. Engaging with big data produced by the interconnected infrastructures, besides the high dimensional and uncertain environment, make traditional methods incapable of addressing these problems since exact modeling...
Article
The Internet of Energy envisions the next generation of smart grids as a highly interconnected network, including advanced metering infrastructures, distributed energy resources, and bidirectional communication systems. The open architecture of IoE-based smart grid results in manifold security concerns, especially the risk of False Data Injection A...
Article
Autonomous vehicles in a platoon determine the control inputs based on the system state information collected and shared by the Internet of Things (IoT) devices. Deep Reinforcement Learning (DRL) is regarded as a potential method for car-following control and has been mostly studied to support a single following vehicle. However, it is more challen...
Article
Full-text available
This paper presents a comprehensive survey of federated reinforcement learning (FRL), an emerging and promising field in reinforcement learning (RL). Starting with a tutorial of federated learning (FL) and RL, we then focus on the introduction of FRL as a new method with great potential by leveraging the basic idea of FL to improve the performance...
Article
A Virtual Power Plant (VPP) is a practical concept that aggregates various Renewable Energy Sources (RESs) to improve energy management efficiency and facilitate energy trading. Operation scheduling for all energy components in VPPs plays a vital role from an energy management perspective. Technical and economic constraints and uncertainties that s...
Preprint
Full-text available
This paper presents a comprehensive survey of Federated Reinforcement Learning (FRL), an emerging and promising field in Reinforcement Learning (RL). Starting with a tutorial of Federated Learning (FL) and RL, we then focus on the introduction of FRL as a new method with great potential by leveraging the basic idea of FL to improve the performance...
Preprint
Full-text available
Smart grids extremely rely on Information and Communications Technology (ICT) and smart meters to control and manage numerous parameters of the network. However, using these infrastructures make smart grids more vulnerable to cyber threats especially electricity theft. Electricity Theft Detection (EDT) algorithms are typically used for such purpose...
Article
Microgrids (MGs) are small, local power grids that can operate independently from the larger utility grid. Combined with the Internet of Things (IoT), a smart MG can leverage the sensory data and machine learning techniques for intelligent energy management. This paper focuses on deep reinforcement learning (DRL)-based energy dispatch for IoT-drive...
Conference Paper
Electricity theft can be considered as a Non-Technical Loss (NTL) in smart grids which is very harmful to the power system. Electricity Theft Detection (ETD) is a procedure to detect atypical behaviors in smart grids which can be achieved via the massive amount of data that is generated by these networks due to using smart meter tools and Informati...
Article
The Internet of Things (IoT) extends the Internet connectivity into billions of IoT devices around the world, where the IoT devices collect and share information to reflect status of the physical world. The Autonomous Control System (ACS), on the other hand, performs control functions on the physical systems without external intervention over an ex...
Article
Full-text available
By leveraging mobile edge computing (MEC), a huge amount of data generated by Internet of Things (IoT) devices can be processed and analyzed at the network edge. However, the MEC system usually only has the limited virtual resources, which are shared and competed by IoT edge applications. Thus, we propose a resource allocation policy for the IoT ed...
Preprint
As a highly scalable permissioned blockchain platform, Hyperledger Fabric supports a wide range of industry use cases ranging from governance to finance. In this paper, we propose a model to analyze the performance of a Hyperledgerbased system by using Generalised Stochastic Petri Nets (GSPN). This model decomposes a transaction flow into multiple...
Preprint
This paper focuses on deep reinforcement learning (DRL)-based energy dispatch for isolated microgrids (MGs) with diesel generators (DGs), photovoltaic (PV) panels, and a battery. A finite-horizon Partial Observable Markov Decision Process (POMDP) model is formulated and solved by learning from historical data to capture the uncertainty in future el...
Article
As a highly scalable permissioned blockchain platform, Hyperledger Fabric supports a wide range of industry use cases ranging from governance to finance. In this paper, we propose a model to analyze the performance of a Hyperledger-based system by using Generalized Stochastic Petri Nets (GSPN). This model decomposes a transaction flow into multiple...
Article
Full-text available
Patent citations are significant components of patents, which play a vital role in the implementation of patent analysis. However, most of the existed models only focus on the text of patents and do not realize that citations can remedy missing information in the text. A method for citation modeling in patent analysis is proposed to generate patent...
Article
Full-text available
By leveraging the concept of mobile edge computing (MEC), massive amount of data generated by a large number of Internet of Things (IoT) devices could be offloaded to MEC server at the edge of wireless network for further computational intensive processing. However, due to the resource constraint of IoT devices and wireless network, both the commun...
Preprint
Full-text available
The Internet of Things (IoT) extends the Internet connectivity into billions of IoT devices around the world, which collect and share information to reflect the status of physical world. The Autonomous Control System (ACS), on the other hand, performs control functions on the physical systems without external intervention over an extended period of...
Preprint
By leveraging the concept of mobile edge computing (MEC), massive amount of data generated by a large number of Internet of Things (IoT) devices could be offloaded to MEC server at the edge of wireless network for further computational intensive processing. However, due to the resource constraint of IoT devices and wireless network, both the commun...
Preprint
Full-text available
The number of approved patents worldwide increases rapidly each year, which requires new patent analytics to efficiently mine the valuable information attached to these patents. Vector space model (VSM) represents documents as high-dimensional vectors, where each dimension corresponds to a unique term. While originally proposed for information retr...
Article
Full-text available
The number of approved patents worldwide increases rapidly each year, which requires new patent analytics to efficiently mine the valuable information attached to these patents. Vector space model (VSM) represents documents as high-dimensional vectors, where each dimension corresponds to a unique term. While originally proposed for information retr...
Article
Full-text available
The Internet of Things (IoT) connects a huge number of resource-constraint IoT devices to the Internet, which generate massive amount of data that can be offloaded to the cloud for computation. As some of the applications may require very low latency, the emerging mobile edge computing (MEC) architecture offers cloud services by deploying MEC serve...
Preprint
In order to maximize detection precision rate as well as the recall rate, this paper proposes an in-vehicle multi-source fusion scheme in Keyword Spotting (KWS) System for vehicle applications. Vehicle information, as a new source for the original system, is collected by an in-vehicle data acquisition platform while the user is driving. A Deep Neur...
Article
Full-text available
Emission trading policy provides a new approach using economic incentives to control environmental pollution efficiently. Legal polluters can trade emission permits with each other through a trusted trading system, which lacks security and credibility due to its centralization nowadays. Permissioned blockchain utilize a decentralized way to store p...
Article
Full-text available
Content caching has brought huge potential for the provisioning of non-safety related infotainment services in future vehicular networks. Assisted by multi-access edge computing, roadside units (RSUs) could become cache-capable and offer fast caching services to moving vehicles for content providers. On the other hand, deep learning makes it possib...
Article
Full-text available
To improve safety and efficiency of transportation system, an effective approach is vehicle platooning, in which a group of vehicles maintains a pre-defined moving pattern by minimizing tracking error of each vehicle. As a networked control process, platooning control relies on the cooperative awareness messages (CAMs) periodically exchange in the...
Article
Full-text available
A Sybil attacker is able to obtain more than one identities and disguise as multiple vehicles in order to interfere the normal operations of the Connected Vehicle System (CVS). In this paper, we propose a novel classifier to detect Sybil attackers according to their mobility behaviors. Specifically, three levels of Sybil attackers are first defined...
Article
Full-text available
Edge caching enables mobile users to fetch contents from cache servers deployed at base stations or even closer to users, with the aim of avoiding latency and improving the overall user experience while reducing backhaul/fronthaul bandwidth use. While sophisticated edge caching policies have been extensively studied in recent works, the practical i...
Article
Full-text available
Vehicular networks enable vehicles to generate and broadcast messages in order to improve traffic safety and efficiency. However, due to the non-trusted environments, it is difficult for vehicles to evaluate the credibilities of received messages. In this paper, we propose a decentralized trust management system in vehicular networks based on block...
Chapter
HSR has been developed rapidly all over the world, which puts forward requirements for a reliable and efficient wireless communication system between the moving train and the ground. According to International Union of Railways (UIC) E-Train Project, the train-ground wireless communication services for HSR system mainly include the train control se...
Chapter
Recently, high-speed railway (HSR) has been developed rapidly all over the world, which puts forward requirements for a reliable and efficient wireless communication system between the moving train and the ground. It is important to design the next generation HSR communications system based on LTE technology while addressing the specific challenges...
Chapter
In recent years, a new paradigm for communication called cooperative communications has been proposed for which initial information theoretic studies have shown the potential for improvements in capacity over traditional multi-hop wireless networks. Cooperative communication involves exploiting the broadcast nature of the wireless medium to form vi...
Chapter
High-speed railway (HSR) communications will become a key feature supported by intelligent transportation communication systems. To the end of 2015, the operating mileage of China railway has reached 121,000 km, and the operating mileage of China HSR has reached 19,000 km, which accounting for more than 60% of the world’s HSR operation mileage, and...
Chapter
In this chapter, we study radio propagation and wireless channels for railway communications. The first part of the chapter focuses on definitions of propagation scenarios. To begin with, high-speed railway propagation scenarios are partitioned, and the characteristics of each scenario are described in detail. Then, traditional concepts of railway...
Chapter
The railway broadband mobile communication systems are required to be continuous, high capable, extremely reliable, and bidirectional [1–2]. Unlike wired channels, the radio channels between train and Infrastructure are random dynamic and unpredictable [3–4]. Thus, it is important to evaluate the performance for railway broadband mobile communicati...
Chapter
High-speed railway (HSR) communications will become a key feature supported by intelligent transportation communication systems. The increasing demand for HSR communications leads to significant attention on the study of radio resource management (RRM), which enables efficient resource utilization and improved system performance. RRM design is a ch...
Chapter
In this chapter covers security schemes of dedicated mobile communications for railway. Due to the control signal is transmitted via wireless channel, communication security is crucial to the whole rail transit system. Although currently the mobile communication infrastructure in railway is based on public cellular mobile communications, considerin...
Article
Full-text available
Driven by the rapid development of wireless communication system, more and more vehicular services can be efficiently supported via vehicle-to-everything (V2X) communications. In order to allocate radio resource with the reasonable implementation complexity in dense urban intersection, a two-stage allocation algorithm is proposed in this paper, who...
Article
Full-text available
With the rapid development of smart driving and communications technologies, an increasing number of vehicles are cooperating with each other to improve traffic efficiency and travel safety. This paper conducts a comprehensive survey of multi-vehicle cooperation from the aspects of control and communication. Firstly, three typical multi-vehicle coo...
Article
The demand for vehicular mobile data services has increased exponentially, which necessitates alternative data pipes for vehicular users other than the cellular network and dedicated short-range communication (DSRC). In this paper, we study the performance of underlaid vehicular device-to-device (V-D2D) communications, where the cellular uplink res...
Article
Full-text available
Public healthcare has been paid an increasing attention given the exponential growth human population and medical expenses. It is well known that an effective health monitoring system can detect abnormalities of health conditions in time and make diagnoses according to the gleaned data. As a vital approach to diagnose heart diseases, ECG monitoring...
Article
Full-text available
For Industrial Wireless Sensor Networks, it is essential to reliably sense and deliver the environmental data on time to avoid system malfunction. While energy harvesting is a promising technique to extend the lifetime of sensor nodes, it also brings new challenges for system reliability due to the stochastic nature of the harvested energy. In this...
Preprint
For Industrial Wireless Sensor Networks, it is essential to reliably sense and deliver the environmental data on time to avoid system malfunction. While energy harvesting is a promising technique to extend the lifetime of sensor nodes, it also brings new challenges for system reliability due to the stochastic nature of the harvested energy. In this...
Article
In Part I of this paper ('Delay-Optimal Dynamic Mode Selection and Resource Allocation in Device-To-Device Communications-Part I: Optimal Policy'), we investigated dynamic mode selection and subchannel allocation for an orthogonal frequency-division multiple access (OFDMA) cellular network with device-To-device (D2D) communications to minimize the...
Article
Full-text available
Wireless sensor networks (WSNs) are effective for locating and tracking people and objects in various industrial environments. Since energy consumption is critical to prolonging the lifespan of WSNs, we propose an energy-efficient LOcalization and Tracking} (eLOT) system, using low-cost and portable hardware to enable highly accurate tracking of ta...
Preprint
Wireless sensor networks (WSNs) are effective for locating and tracking people and objects in various industrial environments. Since energy consumption is critical to prolonging the lifespan of WSNs, we propose an energy-efficient LOcalization and Tracking} (eLOT) system, using low-cost and portable hardware to enable highly accurate tracking of ta...
Article
Full-text available
With the rapid development and application of the mobile Internet, huge amounts of user data are generated and collected every day. How to take full advantages of these ubiquitous data is becoming the essential aspect of a recommender system. Collaborative filtering (CF) has been widely studied and utilized to predict the interests of mobile users...
Article
Full-text available
The pervasive increasing mobile devices and explosively increasing data traffic pose imminent challenges on wireless network design. Device-to-device (D2D) communication is envisioned to play a key role in the fifth generation cellular networks to efficiently support much larger and more diverse set of devices. This paper investigates the mode sele...
Article
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Vehicular ad hoc networks are expected to significantly improve traffic safety and transportation efficiency while providing a comfortable driving experience. However, available communication, storage, and computation resources of the connected vehicles are not well utilized to meet the service requirements of intelligent transportation systems. Ve...
Article
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Heterogeneous Vehicular NETworks (HetVNETs) can meet various quality-of-service (QoS) requirements for intelligent transport system (ITS) services by integrating different access networks coherently. However, the current network architecture for HetVNET cannot efficiently deal with the increasing demands of rapidly changing network landscape. Thank...
Article
Millimeter wave (mmWave) communication is a promising solution for future fifth generation (5G) cellular networks to offer extremely high capacity. Because of the propagation characteristics of mmWave band, 5G users with high mobility in metropolitan areas will suffer frequent link outages resulting in challenges on video quality provisioning. In t...
Conference Paper
Full-text available
Spectrum partition and mode selection are two fundamental issues in D2D overlaid cellular networks, whose performance has been studied at the packet level for a static user population assuming infinite backlogs. In this paper, we aim at the flow-level performance with user dynamics governed by the arrival and completion of random service demands ov...
Article
Background: Compared with commercial SCADA (Supervisory Control and Data Acquisition) software, EPICS (Experimental Physics and Industrial Control System) control system has no uniform way for software management at present. Developers in different projects deploy and invoke EPICS software modules in different ways. However, it is particularly impo...
Article
Full-text available
The communication delay, which has great impact on vehicle-to-infrastructure (V2I) networks, faces a large challenge on account of complex network topology. In this paper, a novel architecture that integrates LTE networks with IEEE 802.11 based Vehicle Ad Hoc Networks (VANETs) is proposed, due to their high data transmission rates and wide coverage...
Article
For the realization of real-time detection of nitrogen concentration in the process of automatic mixed liquid fertilizer, a detection device was designed, which was mainly composed of a nitrate ion selective electrode, an electrode signal conditioning circuit, a temperature sensor, and a data acquisition and display circuit. There was a one-to-one...
Data
Full-text available
Wireless networks are expected to support a diverse range of quality of service requirements and traffic characteristics. This paper undertakes stochastic performance analysis of a wireless finite-state Markov channel (FSMC) by using {\em stochastic network calculus}. Particularly, delay and backlog upper bounds are derived directly based on the an...