Evaluation of an OPNET Model for Unmanned Aerial Vehicle Networks

The concept of Unmanned Aerial Vehicles (UAVs) was first used as early as the American Civil War, when the North and the South unsuccessfully attempted to launch balloons with explosive devices. Since the American Civil War, the UAV concept has been used in all subsequent military operations. Over the last few years, there has been an explosion in the use of UAVs in military operations, as well as civilian and commercial applications. UAV Mobile Ad Hoc Networks (MANETs) are fast becoming essential to conducting Network-Centric Warfare (NCW). As of October 2006, coalition UAVs, exclusive of hand-launched systems, had flown almost 400,000 flight hours in support of Operations Enduring Freedom and Iraqi Freedom [1]. This study develops a verified network model that emulates UAV network behavior during flight, using a leading simulation tool. A flexible modeling and simulation environment is developed to test proposed technologies against realistic mission scenarios. The simulation model evaluation is performed and findings documented. These simulations are designed to understand the characteristics and essential performance parameters of the delivered model. A statistical analysis is performed to explain results obtained, and identify potential performance irregularities. A systemic approach is taken during the preparation and execution simulation phases to avoid producing misleading results

Propagation channel characterisation and modelling for high-speed train communication systems

High-mobility scenarios, e.g., High-Speed Train (HST) scenarios, are expected to be typical scenarios for the Fifth Generation (5G) communication systems. With the rapid development of HSTs, an increasing volume of wireless communication data is required to be transferred to train passengers. HST users demand high network capacity and reliable communication services regardless of their locations or speeds, which are beyond the capability of current HST communication systems. The features of HST channels are significantly different from those of low-mobility cellular communication systems. For a proper design and evaluation of future HST wireless communication systems, we need accurate channel models that can mimic the underlying channel characteristics, especially the non-stationarity for different HST scenarios. Inspired by the lack of such accurate HST channel models in the literature, this PhD project is devoted to the modelling and simulation of non-stationary Multiple-Input Multiple-Output (MIMO) channels for HST communication systems. In this thesis, we first give a comprehensive review of the measurement campaigns conducted in different HST scenarios and address the recent advances in HST channel models. We also highlight the key challenges of HST channel measurements and models. Then, we study the characterisation of non-stationary channels and propose a theoretical framework for deriving the statistical properties of these channels. HST wireless communication systems encounter different channel conditions due to the difference of surrounding geographical environments or scenarios. HST channel models in the literature have either considered large-scale parameters only and/or neglected the non-stationarity of HST channels and/or only consider one of the HST scenarios. Therefore, we propose a novel generic non-stationary Geometry-Based Stochastic Model (GBSM) for wideband MIMO HST channels in different HST scenarios, i.e., open space, viaduct, and cutting. The corresponding simulation model is then developed with angular parameters calculated by the Modified Method of Equal Area (MMEA). The system functions and statistical properties of the proposed channel models are thoroughly studied. The proposed generic non-stationary HST channel models are verified by measurements in terms of stationary time for the open space scenario and the Autocorrelation Function (ACF), Level Crossing Rate (LCR), and stationary distance for the viaduct and cutting scenarios. Transmission techniques which are capable of utilising Three-Dimensional (3D) spatial dimensions are significant for the development of future communication systems. Consequently, 3D MIMO channel models are critical for the development and evaluation of these techniques. Therefore, we propose a novel 3D generic non-stationary GBSM for wideband MIMO HST channels in the most common HST scenarios. The corresponding simulation model is then developed with angular parameters calculated by the Method of Equal Volume (MEV). The proposed models considers several timevarying channel parameters, such as the angular parameters, the number of taps, the Ricean K-factor, and the actual distance between the Transmitter (Tx) and Receiver (Rx). Based on the proposed generic models, we investigate the impact of the elevation angle on some of the channel statistical properties. The proposed 3D generic models are verified using relevant measurement data. Most standard channel models in the literature, like Universal Mobile Telecommunications System (UMTS), COST 2100, and IMT-2000 failed to introduce any of the HST scenarios. Even for the standard channel models which introduced a HST scenario, like IMT-Advanced (IMT-A) and WINNER II channel models, they offer stationary intervals that are noticeably longer than those in measured HST channels. This has inspired us to propose a non-stationary IMT-A channel model with time-varying parameters including the number of clusters, powers, delays of the clusters, and angular parameters. Based on the proposed non-stationary IMT-A channel model, important statistical properties, i.e., the time-variant spatial Cross-correlation Function (CCF) and time-variant ACF, are derived and analysed. Simulation results demonstrate that the stationary interval of the developed non-stationary IMT-A channel model can match that of relevant HST measurement data. In summary, the proposed theoretical and simulation models are indispensable for the design, testing, and performance evaluation of 5G high-mobility wireless communication systems in general and HST ones in specific

Proceedings of the Conference on Production Systems and Logistics: CPSL 2022

[no abstract available

Mediating the Spatiality of Conflicts:

Conflict, when dislodged from its conventional understanding as a process and system of war and destruction exclusively, may be apprehended as an experimental method for analysis and synthesis, as a potent resource for pedagogy, for disruptive design and for the production of theory. In this sense, conflict produces more than the eradication of (the possibility of) life and its supporting structures: conflict produces transitional spaces at different scales, of differentiated material ecologies and site-specific meanings in relation to their global position. Conflicts are both locations and explanations of often ‘seductive’ images of destruction offered by popular (and other) media: ruined architectures, dead (or barely alive) bodies, forced migratory movements, impermanent infrastructures and settlements, as well as the tracing and construction of borders, real-estate driven post-war reconstruction processes, etc. The emphasis on the mediatic aspect in the concept of conflict, may be seen as a way of triggering trans- and interdisciplinary discussions, conversations and encounters that serve as a negotiation between conditions of violence and new — or alternative — possibilities for everyday life. Artistic mediations could be as effective as violence in resolving conflicts, but operate through other means and through other channels, thus truly producing new power relations and alternative ways of political struggle. This exposing of conflict and violence through the artistic work is an activist act, but more importantly an artistic and technological mediation. The agency of the artistic work in terms of conflict, then, is situated in the capacity of visualising the conflict, creating awareness of its consequences, its side-effects, its collateral damage. And the creating of awareness and the becoming of fertile ground for protest and the creation of alternative realities. At a three-day conference held at the TU Delft on November 6-8, 2019 researchers, scholars, activists, practitioners and artists presented individual papers that addressed the relationships between spatiality, mediation and conflict from a variety of perspectives. In addition to academic paper contributions, the conference welcomed other proposals in different formats and media: audio-visual material (film, video, photography), digital or physical archives, experimental design proposals, installations, performances, etc. The thematic core of the conference explored new — or innovative — theoretical and methodological approaches and insights on: (1) Spaces of conflict as transitional spaces of material interactions between violence and everyday life; and (2) Spaces of memory as transformative space of violence)

Mediating the Spatiality of Conflicts:

Conflict, when dislodged from its conventional understanding as a process and system of war and destruction exclusively, may be apprehended as an experimental method for analysis and synthesis, as a potent resource for pedagogy, for disruptive design and for the production of theory. In this sense, conflict produces more than the eradication of (the possibility of) life and its supporting structures: conflict produces transitional spaces at different scales, of differentiated material ecologies and site-specific meanings in relation to their global position. Conflicts are both locations and explanations of often ‘seductive’ images of destruction offered by popular (and other) media: ruined architectures, dead (or barely alive) bodies, forced migratory movements, impermanent infrastructures and settlements, as well as the tracing and construction of borders, real-estate driven post-war reconstruction processes, etc. The emphasis on the mediatic aspect in the concept of conflict, may be seen as a way of triggering trans- and interdisciplinary discussions, conversations and encounters that serve as a negotiation between conditions of violence and new — or alternative — possibilities for everyday life. Artistic mediations could be as effective as violence in resolving conflicts, but operate through other means and through other channels, thus truly producing new power relations and alternative ways of political struggle. This exposing of conflict and violence through the artistic work is an activist act, but more importantly an artistic and technological mediation. The agency of the artistic work in terms of conflict, then, is situated in the capacity of visualising the conflict, creating awareness of its consequences, its side-effects, its collateral damage. And the creating of awareness and the becoming of fertile ground for protest and the creation of alternative realities. At a three-day conference held at the TU Delft on November 6-8, 2019 researchers, scholars, activists, practitioners and artists presented individual papers that addressed the relationships between spatiality, mediation and conflict from a variety of perspectives. In addition to academic paper contributions, the conference welcomed other proposals in different formats and media: audio-visual material (film, video, photography), digital or physical archives, experimental design proposals, installations, performances, etc. The thematic core of the conference explored new — or innovative — theoretical and methodological approaches and insights on: (1) Spaces of conflict as transitional spaces of material interactions between violence and everyday life; and (2) Spaces of memory as transformative space of violence)

Undergraduate Catalogue 2011-2013

https://digitalscholarship.tnstate.edu/undergraduatecatalogues/1003/thumbnail.jp

Quantifying catchment-scale coarse sediment dynamics in British rivers

It has become increasingly clear that river channel sediment dynamics must be taken into account within British flood risk management because changes in channel morphology resulting from sediment transfer can have an impact on channel flood capacity. It is also recognised that an understanding of catchment-scale sediment dynamics is desirable with respect to many other aspects of river management. However, despite this recognition, application of existing approaches that account for coarse sediment dynamics has been limited within British river management. Based on these considerations, this study aims to develop and substantiate a new approach that quantitatively accounts for catchment-scale coarse sediment dynamics in British rivers. These research efforts contribute to the activity of the Flood Risk Management Research Consortium (http://www.floodrisk.org.uk/) A review of the availability and accuracy of data sources useful to considerations of coarse sediment dynamics reveals that only discharge, channel slope, and channel width can be represented widely at the catchment-scale. As a result, none of the approaches currently available to account for coarse sediment dynamics were found to be both scientifically robust and practically applicable at the catchment-scale. This leads to the conclusion that the most suitable approach to account for coarse sediment dynamics at the catchment-scale in British rivers is a reach-based sediment balance model, using no more than slope, width and discharge data. A new reach-based sediment balance model, ST:REAM (Sediment Transport: Reach Equilibrium Assessment Method), is developed. It has several unique features including: representation of the entire catchment network; automatic delineation of the catchment network into functional reaches using a zonation algorithm; application of a new general formula for the prediction of bed surface material transport rate; and adoption of an assumption that makes it unnecessary to collect bed material size data. The outputs from ST:REAM are in the form of predicted Capacity Supply Ratios which compare the annual mass of sediment predicted to enter a reach with the annual mass of sediment predicted to leave it. Initial assessment of ST:REAM using two test catchments shows that it can produce a reasonable representation of observed, broad-scale sediment dynamics. The accuracy of its predictions decreases when attempting to incorporate downstream variability in bed material size into the model, and scale issues are encountered when attempting to increase the resolution at which reaches are identified by the zonation algorithm. ST:REAM has many potential applications within river management, but it is of most value when providing a broad-scale picture of predicted reach sediment balances throughout the drainage network. As well as the practical applications of ST:REAM, the research contained within this thesis has important theoretical implications, relating both to the insights it provides on catchment-scale sediment dynamics in particular and methodological and foundational developments in the field of sediment studies more generally. Online version lacks Appendices, which were submitted on CD-ROM accompanying printed version

Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018