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Articles 1 - 30 of 76
Full-Text Articles in Systems and Communications
Value Of Service-Oriented Multi-Service Provisioning And Resource Allocation In Integrated Localization, Sensing And Communication Systems, Biwei Li
Electronic Thesis and Dissertation Repository
The unprecedented proliferation of wireless infrastructures and their ongoing convergence with diverse industrial Internet of Things (IoT) applications introduce new demands for upcoming wireless networks. In response to such diversity of demands, envisioned future wireless networks must have multiple beyond communication capabilities, such as localization and sensing. To efficiently utilize, allocate, and manage these capabilities, the integration of localization, sensing, and communication (ILSAC) within a unified wireless system structure is of utmost importance. However, the seamless integration of ILSAC into intricate network infrastructures is encumbered by critical challenges, including high-accuracy localization/sensing algorithm, efficient resource management and allocation scheme, and robust …
Multi-Dimensional Qos And Collaborative Mac Layer Design For Dense, Diverse, And Dynamic Iot Network, Jiyang Bai
Multi-Dimensional Qos And Collaborative Mac Layer Design For Dense, Diverse, And Dynamic Iot Network, Jiyang Bai
Electronic Thesis and Dissertation Repository
With the ubiquitous proliferation of Internet of Thing (IoT) devices, Access Points (APs) of future Wireless Fidelity (Wi-Fi) networks are expected to support dense Stations (STAs) with diverse Quality-of-Service (QoS) requirements under dynamic channel conditions. On account of high access collision and optimization problem complexity, the performance degradation brings new challenges to the existing Media Access Control (MAC) layer design in Wi-Fi. This thesis proposes novel technologies to enable low-latency high-performance MAC layer designs, which support dense access of STAs with real-time solutions of resource allocation and link adaptation problems. Both grouping and collaborative architectures are utilized based on game …
Cluster-Based Station Reporting And Multi-Ap Coordination In Wi-Fi Networks, Zeyad Abdelmageid
Cluster-Based Station Reporting And Multi-Ap Coordination In Wi-Fi Networks, Zeyad Abdelmageid
Electronic Thesis and Dissertation Repository
Due to the few available Wi-Fi channels and the existence of other technologies, the channel selected by an access point (AP) to be assigned to the network is of extreme importance for network performance due to different interference conditions at different channels. While channel selection algorithms have been proposed, very few of them are user-centric, which could incur a large signaling overhead. As a result, in this thesis, a channel selection algorithm with a low-overhead station (STA) reporting mechanism is proposed, which utilizes the spatial correlation of interference by clustering close-by STAs in order to reduce the feedback overhead by …
Low Overhead And Application-Oriented Synchronization In Heterogeneous Internet Of Things Systems, Haide Wang
Low Overhead And Application-Oriented Synchronization In Heterogeneous Internet Of Things Systems, Haide Wang
Electronic Thesis and Dissertation Repository
Recent evolution in the Internet of Things (IoT) and Cyber–physical systems (CPS) is expected to change everyday life of its users by enabling low latency and reliable communication, coordinated task execution and real time data processing among pervasive intelligence through the communication network. Precise time synchronization, as a prerequisite for a chronological ordering of information or synchronous execution, has become a vital constituent for many time-sensitive applications.
On one hand, Internet of Things (IoT) systems rely heavily on the temporal coherence among its distributed constituents during data fusion and analysis, however the existing solutions for data synchronization, do not easily …
Efficient Discovery And Utilization Of Radio Information In Ultra-Dense Heterogeneous 3d Wireless Networks, Mattaka Gamage Samantha Sriyananda
Efficient Discovery And Utilization Of Radio Information In Ultra-Dense Heterogeneous 3d Wireless Networks, Mattaka Gamage Samantha Sriyananda
Electronic Thesis and Dissertation Repository
Emergence of new applications, industrial automation and the explosive boost of smart concepts have led to an environment with rapidly increasing device densification and service diversification. This revolutionary upward trend has led the upcoming 6th-Generation (6G) and beyond communication systems to be globally available communication, computing and intelligent systems seamlessly connecting devices, services and infrastructure facilities. In this kind of environment, scarcity of radio resources would be upshot to an unimaginably high level compelling them to be very efficiently utilized. In this case, timely action is taken to deviate from approximate site-specific 2-Dimensional (2D) network concepts in radio resource utilization …
Introduction To Pub/Sub Systems Using Opcua, Mete Isiksalan
Introduction To Pub/Sub Systems Using Opcua, Mete Isiksalan
Undergraduate Student Research Internships Conference
The purpose of the project was to learn and implement the fundamental basics of OPCUA system architecture using pub/sub systems. The system allows the users to create multiple different publishers and subscribers while accessing data from a local server and a primary HTTP server. The system is designed to be a multi-client and multi-server system to simulate real-life scenarios while having two different sources of generated values to send via sockets in OPCUA protocols, multiple different APIs were used for the clients on how they retrieve data as well.
Effective Resource Scheduling For Collaborative Computing In Edge-Assisted Internet Of Things Systems, Qianqian Wang
Effective Resource Scheduling For Collaborative Computing In Edge-Assisted Internet Of Things Systems, Qianqian Wang
Electronic Thesis and Dissertation Repository
Along with rapidly evolving communications technologies and data analytics, Internet of Things (IoT) systems interconnect billions of smart devices to gather, exchange, analyze data, and perform tasks autonomously, which poses a huge pressure on IoT devices' computing capabilities. Taking advantage of collaborative computing enabled by cloud computing and edge computing technologies, IoT devices can offload computation tasks to idle computing devices and remote servers, thus alleviating their pressure. However, scheduling resources effectively to realize collaborative computing remains a severe challenge due to diverse application objectives, limited distributed resources, and unpredictable environments. To overcome the above challenges, this thesis aims to …
Non-Orthogonal Multi-Dimensional Modulation And Nonlinear Distortion Compensation For Beyond 5g, Thakshanth Uthayakumar
Non-Orthogonal Multi-Dimensional Modulation And Nonlinear Distortion Compensation For Beyond 5g, Thakshanth Uthayakumar
Electronic Thesis and Dissertation Repository
The introduction of new advanced technologies such as higher carrier frequencies, ultra-wide bandwidth, and increased transmission rate in 5G to support ever growing quality-of-service (QoS) demands have brought new challenges such as transmitter-receiver pair specific and domain specific non-orthogonality induced among spatial, time-frequency, and delay-doppler domain radio resource blocks and nonlinear distortions induced among multiple-input multiple-output (MIMO) antennas in spatial domain. In such conditions, current communication systems encounter severe performance degradation and incur higher operational cost. Based on this observation, this thesis aims at creating new multi-dimensional modulation techniques and nonlinear predistortion architectures to achieve higher communication performance with less …
Coexistence Of Wi-Fi And 5g Nr-U In The Unlicensed Band, Sara Saud Zimmo
Coexistence Of Wi-Fi And 5g Nr-U In The Unlicensed Band, Sara Saud Zimmo
Electronic Thesis and Dissertation Repository
The communications industry continues to evolve to meet the ever-growing demands of fast connectivity and higher energy-efficiency and has emerged the concept of Internet of Things (IoT) systems. IoT devices can be run on Wi-Fi or cellular network, helping businesses to receive higher return on investments.
As billions of devices on cellular networks operate on the limited licensed spectrum, it is becoming scarcer. Mobile network operators are investigating to access the immense unlicensed spectrum, on which Wi-Fi is prominently operated. Managing this coexistence between the cellular and Wi-Fi networks poses several challenges.
One challenge is the spectrum sharing that affects …
Situation-Aware Quality Of Service Enhancement For Heterogeneous Ultra-Dense Wireless Iot Networks, Sabin Bhandari
Situation-Aware Quality Of Service Enhancement For Heterogeneous Ultra-Dense Wireless Iot Networks, Sabin Bhandari
Electronic Thesis and Dissertation Repository
By engaging a massive number of heterogeneous devices, future Internet of Things (IoT) systems are expected to support diverse applications ranging from eHealthcare to industrial control. In highly-dense deployment scenarios such as Industrial IoT (IIoT) systems, meeting the stringent Quality of Service (QoS) requirements such as low-latency and high reliability becomes challenging due to the uncertainty and dynamics within the IoT networks. To enhance the overall QoS performance, this thesis aims to address the technical challenges of IoT networks. Firstly, to enhance the network reliability, a cloud-assisted priority-based channel access and data aggregation scheme is proposed to minimize the network …
Leveraging Machine Learning Techniques Towards Intelligent Networking Automation, Cesar A. Gomez
Leveraging Machine Learning Techniques Towards Intelligent Networking Automation, Cesar A. Gomez
Electronic Thesis and Dissertation Repository
In this thesis, we address some of the challenges that the Intelligent Networking Automation (INA) paradigm poses. Our goal is to design schemes leveraging Machine Learning (ML) techniques to cope with situations that involve hard decision-making actions. The proposed solutions are data-driven and consist of an agent that operates at network elements such as routers, switches, or network servers. The data are gathered from realistic scenarios, either actual network deployments or emulated environments. To evaluate the enhancements that the designed schemes provide, we compare our solutions to non-intelligent ones. Additionally, we assess the trade-off between the obtained improvements and the …
Consensus-Enabled And Value-Oriented Collaboration In Distributed Iot Systems: Mechanisms, Design, And Implementation, Ruitao Chen
Consensus-Enabled And Value-Oriented Collaboration In Distributed Iot Systems: Mechanisms, Design, And Implementation, Ruitao Chen
Electronic Thesis and Dissertation Repository
The ongoing convergence of Internet of Things (IoT), artificial intelligence and big data analytics has inspired many innovative IoT applications. Enabling these new applications requires accurate and reliable capabilities in data sensing, exchange and processing, which can be best fulfilled by collaborative IoT systems. Nevertheless, the dynamic condition of IoT networks may lead to ever-changing demand and objectives among devices, making it difficult for reliable and efficient collaboration. To overcome these challenges, this thesis develops a new framework on consensus-enabled and value-oriented collaboration, which resolves two critical technical challenges, i.e., low latency consensus creation and value-oriented decision-making, to enable collective …
Development Of A Wireless Telemetry Load And Displacement Sensor For Orthopaedic Applications, William Anderson
Development Of A Wireless Telemetry Load And Displacement Sensor For Orthopaedic Applications, William Anderson
Electronic Thesis and Dissertation Repository
Due to sensor size and supporting circuitry, in vivo load and deformation measurements are currently restricted to applications within larger orthopaedic implants. The objective of this thesis is to repurpose a commercially available low-power, miniature, wireless, telemetric, tire-pressure sensor (FXTH87) to measure load and deformation for future use in biomechanical applications. The capacitive transducer membrane of the FXTH87 was modified, and a relationship was reported between applied compressive deformation and sensor signal value. The sensor package was embedded within a deformable enclosure to illustrate potential applications of the sensor for monitoring load. Finite element analysis was an effective tool to …
Intelligent And Low Overhead Network Synchronization Over Large-Scale Industrial Internet Of Things Systems, Pengyi Jia
Intelligent And Low Overhead Network Synchronization Over Large-Scale Industrial Internet Of Things Systems, Pengyi Jia
Electronic Thesis and Dissertation Repository
With the extensive development of information and communication technologies and vertical industry applications, industrial IoT (IIoT) systems are expected to enable a wide variety of applications, including advanced manufacturing, networked control, and smart supply chain, which all exclusively hinge on the efficient cooperation and coordination among the involved IIoT machines and infrastructures. The ubiquitous connection among IIoT entities and the associated exchange of collaborative information necessitate the achievement of accurate network synchronization, which can guarantee the temporal alignment of the critical information. To enhance the temporal correlation of heterogeneous devices in large-scale IIoT systems, this thesis aims at designing industry-oriented …
Towards Efficient And Secure Iiot: Solutions For The Sensing Domain, Elena Uchiteleva
Towards Efficient And Secure Iiot: Solutions For The Sensing Domain, Elena Uchiteleva
Electronic Thesis and Dissertation Repository
This work explores reduced complexity solutions for the increased efficiency and safety of the industrial Internet of Things (IIoT) sensing domain. Resource virtualization, security, and predictive modeling are the main subjects of these studies.
The first solution is a joint throughput and time-resource allocation scheme for virtualization of IEEE 802.15.4-based wireless sensor networks. Virtualization is realized through the utilization of the guaranteed time slot mechanism for scheduling on the medium access control (MAC) layer. The solution abstracts resources into logical units that are allocated to segregated applications with different service requirements. The problem is formulated in a linear optimization framework …
Orthogonal Frequency Division Multiplexing System With Index Modulations For Wireless Communication, Ibrahim M Abdalla Aboharba
Orthogonal Frequency Division Multiplexing System With Index Modulations For Wireless Communication, Ibrahim M Abdalla Aboharba
Electronic Thesis and Dissertation Repository
Orthogonal Frequency Division Multiplexing (OFDM) with Index Modulation (OFDM-IM) system with arbitrary and are suggested and investigated for data transmission over realistic fading and shadowing wireless communication channels. In these OFDM-IM systems, data is conveyed to the receiver using characteristics of signal mapper in the OFDM system and by using indices of active subcarriers dictated by the type of IM employed. Two types of index modulations, arbitrary and Look-Up Table (LUT), are described and examined for selection of active subcarriers in OFDM systems with OOK (ON-OFF Keying), M-QAM (M-ary Quadrature Amplitude Modulation), and M-PSK (M-ary Phase Shift Keying) signal mappers. …
Intelligent Security Provisioning And Trust Management For Future Wireless Communications, He Fang
Intelligent Security Provisioning And Trust Management For Future Wireless Communications, He Fang
Electronic Thesis and Dissertation Repository
The fifth-generation (5G)-and-beyond networks will provide broadband access to a massive number of heterogeneous devices with complex interconnections to support a wide variety of vertical Internet-of-Things (IoT) applications. Any potential security risk in such complex systems could lead to catastrophic consequences and even system failure of critical infrastructures, particularly for applications relying on tight collaborations among distributed devices and facilities. While security is the cornerstone for such applications, trust among entities and information privacy are becoming increasingly important. To effectively support future IoT systems in vertical industry applications, security, trust and privacy should be dealt with integratively due to their …
Novel Estimation And Detection Techniques For 5g Networks, Anas Saci
Novel Estimation And Detection Techniques For 5g Networks, Anas Saci
Electronic Thesis and Dissertation Repository
The thesis presents several detection and estimation techniques that can be incorporated into the fifth-generation (5G) networks. First, the thesis presents a novel system for orthogonal frequency division multiplexing (OFDM) to estimate the channel blindly. The system is based on modulating particular pairs of subcarriers using amplitude shift keying (ASK) and phase-shift keying (PSK) adjacent in the frequency domain, which enables the realization of a decision-directed (DD) one-shot blind channel estimator (OSBCE). The performance of the proposed estimator is evaluated in terms of the mean squared error (MSE), where an accurate analytical expression is derived and verified using Monte Carlo …
Vehicle Networks: Statistical And Game Theoretic Approaches To Their Evaluation And Design, Gleb Dubosarskii
Vehicle Networks: Statistical And Game Theoretic Approaches To Their Evaluation And Design, Gleb Dubosarskii
Electronic Thesis and Dissertation Repository
Vehicle ad hoc networks (VANETs) have become a popular topic in modern research. The main advantages of these networks include: improved security, traffic optimization, and infotainment. However, deploying such networks in practice requires extensive infrastructure. To estimate the network load, one needs to have information about the network, such as the number of clusters, cluster size, etc. Since VANETs are formed by vehicles that rapidly change their location, the network topology is constantly changing, making its analysis by deterministic methods impossible. Therefore, in this dissertation, we use probability theory methods to obtain probability distributions of such fundamental network properties, such …
Edge-Cloud Iot Data Analytics: Intelligence At The Edge With Deep Learning, Ananda Mohon M. Ghosh
Edge-Cloud Iot Data Analytics: Intelligence At The Edge With Deep Learning, Ananda Mohon M. Ghosh
Electronic Thesis and Dissertation Repository
Rapid growth in numbers of connected devices, including sensors, mobile, wearable, and other Internet of Things (IoT) devices, is creating an explosion of data that are moving across the network. To carry out machine learning (ML), IoT data are typically transferred to the cloud or another centralized system for storage and processing; however, this causes latencies and increases network traffic. Edge computing has the potential to remedy those issues by moving computation closer to the network edge and data sources. On the other hand, edge computing is limited in terms of computational power and thus is not well suited for …
Synchrophasor Based Islanding & Open Phase Fault Protection In Distribution Systems, Mansour Jalali
Synchrophasor Based Islanding & Open Phase Fault Protection In Distribution Systems, Mansour Jalali
Electronic Thesis and Dissertation Repository
With the rapid growth of renewable energy resources, energy efficiency initiatives, electric vehicles, energy storage, etc., distribution systems are becoming more complex such that conventional protection, control, and measurement infrastructure – typically concentrated at the main substation, with little to no access to information along the feeder – cannot maintain the reliability of the system without some sort of additional protection, control and measurement functionalities. As an example, a dedicated communication channel for carrying the transfer trip signal from the substation to the Point of Common Coupling (PCC) to prevent islanding operation of alternative resources, has been a requirement for …
Leveraging Cloud-Based Nfv And Sdn Platform Towards Quality-Driven Next-Generation Mobile Networks, Hassan Hawilo
Leveraging Cloud-Based Nfv And Sdn Platform Towards Quality-Driven Next-Generation Mobile Networks, Hassan Hawilo
Electronic Thesis and Dissertation Repository
Network virtualization has become a key approach for Network Service Providers (NSPs) to mitigate the challenge of the continually increasing demands for network services. Tightly coupled with their software components, legacy network devices are difficult to upgrade or modify to meet the dynamically changing end-user needs. To virtualize their infrastructure and mitigate those challenges, NSPs have started to adopt Software Defined Networking (SDN) and Network Function Virtualization (NFV). To this end, this thesis addresses the challenges faced on the road of transforming the legacy networking infrastructure to a more dynamic and agile virtualized environment to meet the rapidly increasing demand …
Blockchain-Based Distributed Network Architecture For Internet Of Things, Min Li
Blockchain-Based Distributed Network Architecture For Internet Of Things, Min Li
Electronic Thesis and Dissertation Repository
IoT networks have already been widely deployed due to their convenience and low-cost advantage. However, due to the lack of strong self-protection mechanisms and the imperfect network architectures, many IoT devices are vulnerable to malicious cyber-attacks, which will further threaten the availability and security of IoT applications. Therefore, securing the network infrastructure while protecting data from malicious or unauthorized devices/users become a vital aspect of IoT network design. In the thesis, two types of IoT security mechanisms are mainly investigated, namely, IoT routing protection and smart community device authentication.
By adopting the distributed consensus mechanism, we propose a blockchain-based reputation …
Exploitation Of Robust Aoa Estimation And Low Overhead Beamforming In Mmwave Mimo System, Yuyan Zhao
Exploitation Of Robust Aoa Estimation And Low Overhead Beamforming In Mmwave Mimo System, Yuyan Zhao
Electronic Thesis and Dissertation Repository
The limited spectral resource for wireless communications and dramatic proliferation of new applications and services directly necessitate the exploitation of millimeter wave (mmWave) communications. One critical enabling technology for mmWave communications is multi-input multi-output (MIMO), which enables other important physical layer techniques, specifically beamforming and antenna array based angle of arrival (AoA) estimation. Deployment of beamforming and AoA estimation has many challenges. Significant training and feedback overhead is required for beamforming, while conventional AoA estimation methods are not fast or robust. Thus, in this thesis, new algorithms are designed for low overhead beamforming, and robust AoA estimation with significantly reduced …
Energy-Efficient Multicarrier And Multicarrier-Cdma Systems, Moftah Ali
Energy-Efficient Multicarrier And Multicarrier-Cdma Systems, Moftah Ali
Electronic Thesis and Dissertation Repository
Design, analysis, and performance of Multicarrier (MC) and Multicarrier-Code Division Multiple Access (MC-CDMA) systems are considered. Specifically, Multicarrier Modulation (MCM) such as Orthogonal Frequency Division Multiplexing (OFDM) is used in these systems with emphasis on energy efficiency. These systems are examined for their performances over frequency-selective and frequency-non-selective channels. Methods are proposed for reduction of energy costs of an OFDM system. They are: i) Clipping (CL) based on symbol statistics; ii) Partial Transmit Sequence (PTS) using Magic square pattern and adjacent partitioning; and iii) Selective Mapping (SLM) and Tone Reservation (TR) with reduced complexity. These methods are described and algorithms …
Data Analytics And Performance Enhancement In Edge-Cloud Collaborative Internet Of Things Systems, Tianqi Yu
Data Analytics And Performance Enhancement In Edge-Cloud Collaborative Internet Of Things Systems, Tianqi Yu
Electronic Thesis and Dissertation Repository
Based on the evolving communications, computing and embedded systems technologies, Internet of Things (IoT) systems can interconnect not only physical users and devices but also virtual services and objects, which have already been applied to many different application scenarios, such as smart home, smart healthcare, and intelligent transportation. With the rapid development, the number of involving devices increases tremendously. The huge number of devices and correspondingly generated data bring critical challenges to the IoT systems. To enhance the overall performance, this thesis aims to address the related technical issues on IoT data processing and physical topology discovery of the subnets …
Analysis, Design And Demonstration Of Control Systems Against Insider Attacks In Cyber-Physical Systems, Xirong Ning
Analysis, Design And Demonstration Of Control Systems Against Insider Attacks In Cyber-Physical Systems, Xirong Ning
Electronic Thesis and Dissertation Repository
This dissertation aims to address the security issues of insider cyber-physical attacks and provide a defense-in-depth attack-resilient control system approach for cyber-physical systems.
Firstly, security analysis for cyber-physical systems is investigated to identify potential risks and potential security enhancements. Vulnerabilities of the system and existing security solutions, including attack prevention, attack detection and attack mitigation strategies are analyzed.
Subsequently, a methodology to analyze and mathematically characterize insider attacks is developed. An attack pattern is introduced to represent key features in an insider cyber-physical attack, which includes attack goals, resources, constraints, modes, as well as probable attack paths. Patterns for such …
Investigation Of Radiation-Hardened Design Of Electronic Systems With Applications To Post-Accident Monitoring For Nuclear Power Plants, Qiang Huang
Electronic Thesis and Dissertation Repository
This research aims at improving the robustness of electronic systems used-in high level radiation environments by combining with radiation-hardened (rad-hardened) design and fault-tolerant techniques based on commercial off-the-shelf (COTS) components. A specific of the research is to use such systems for wireless post-accident monitoring in nuclear power plants (NPPs). More specifically, the following methods and systems are developed and investigated to accomplish expected research objectives: analysis of radiation responses, design of a radiation-tolerant system, implementation of a wireless post-accident monitoring system for NPPs, performance evaluation without repeat physical tests, and experimental validation in a radiation environment.
A method is developed …
Performance Enhancement Of Ieee 802.11ax In Ultra-Dense Wireless Networks, Jiyang Bai
Performance Enhancement Of Ieee 802.11ax In Ultra-Dense Wireless Networks, Jiyang Bai
Electronic Thesis and Dissertation Repository
IEEE 802.11ax, which is one emerging WLAN standard, aims at providing highly efficient communication in ultra-dense wireless networks. However, due to a large number of stations (STAs) in dense deployment scenarios and diverse services to be supported, there are many technical challenges to be overcome. Firstly, the potential high packet collision rate significantly degrades the network efficiency of WLAN. In this thesis, we propose an adaptive station (STA) grouping scheme to overcome this challenge in IEEE 802.11ax using Uplink OFDMA Random Access (UORA). In order to achieve optimal utilization efficiency of resource units (RUs), we first analyze the relationship between …
Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil
Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil
Electronic Thesis and Dissertation Repository
Time synchronization is an issue that affects data accuracy within wireless sensor networks (WSNs). This issue is due to the complex nature of the wireless medium and can be mitigated with accurate time synchronization. This research focuses on the Flooding Time Synchronization Protocol (FTSP) since it is considered as the gold standard for accuracy in WSNs. FTSP minimizes the synchronization error by executing an algorithm that creates a unified time for the network reporting micro-second accuracy. Most synchronization protocols use the FTSP implementation as a benchmark for comparison. The current and only FTSP implementation runs on the TinyOS platform and …