This thesis describes and defends the moving spotlight theory, a metaphysical theory concerning the fundamental temporal structure of reality. The moving spotlight theory has two essential components: first, a thesis about presentness; and second, a thesis about the existence (in the most general sense) of things over time. The first thesis is that exactly one instant of time is absolutely, objectively, non-relatively present. This thesis is usually called the ‘A-theory of time’. (The opposing view, according to which no instant of time is absolutely, objectively, non-relatively present, is usually called the ‘B-theory of time’.) The second thesis is that things neither begin nor cease to exist over time; in other words, that it is always the case that everything exists forever. Following Williamson (2013), I call this thesis permanentism. Historically, the moving spotlight theory has been among the least popular plausible theories of time. However, that is because the view has been badly misconstrued. In this thesis I provide a careful description of the moving spotlight theory and show that moving spotlighters can easily respond to the main arguments that have been raised against their view. I also show that the moving spotlight theory, when correctly understood, is the very best theory of time. In particular, the moving spotlight theory inherits the simplicity, explanatory power, and scientific respectability of permanentism, while at the same time describing a world in which there is genuine time and change. In terms of structure, the thesis has two parts, each containing three chapters. In Chapter One, I introduce the A-theory and defend it against some common objections. In Chapter Two, I describe a version of the moving spotlight theory which I call ‘classic MST’, and argue that if the moving spotlight theory is true, classic MST is true. In Chapter Three, I argue against the traditional method of characterising theories of time, and develop a new method in its place. In Chapter Four, I argue that the A-theory is true. In Chapters Five and Six, I argue that we think and speak as if permanentism is true, so we should accept permanentism. I conclude that the moving spotlight theory, and therefore classic MST, is true.

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Doctor of Philosophy / Computing and Information Sciences / Scott A. DeLoach / Xinming (Simon) Ou / The Moving Target Defense (MTD) concept has been proposed as an approach to rebalance the security landscape by increasing uncertainty and apparent complexity for attackers, reducing their window of opportunity, and raising the costs of their reconnaissance and attack efforts. Intuitively, the idea of applying MTD techniques to a whole IT system should provide enhanced security; however, little research has been done to show that it is feasible or beneficial to the system’s security. This dissertation presents an MTD platform at the whole IT system level in which any component of the IT system can be automatically and reliably replaced with a fresh new one. A component is simply a virtual machine (VM) instance or a cluster of instances. There are a number of security benefits when leveraging such an MTD platform. Replacing a VM instance with a new one with the most up-to-date operating system and applications eliminates security problems caused by unpatched vulnerabilities and all the privileges the attacker has obtained on the old instance. Configuration parameters for the new instance, such as IP address, port numbers for services, and credentials, can be changed from the old ones, invalidating the knowledge the attackers already obtained and forcing them to redo the work to re-compromise the new instance. In spite of these obvious security benefits, building a system that supports live replacement with minimal to no disruption to the IT system’s normal operations is difficult. Modern enterprise IT systems have complex dependencies among services so that changing even a single instance will almost certainly disrupt the dependent services. Therefore, the replacement of instances must be carefully orchestrated with updating the settings of the dependent instances. This orchestration of changes is notoriously error-prone if done manually, however, limited tool support is available to automate this process. We designed and built a framework (ANCOR) that captures the requirements and needs of a whole IT system (in particular, dependencies among various services) and compiles them into a working IT system. ANCOR is at the core of the proposed MTD platform (ANCOR-MTD) and enables automated live instance replacements. In order to evaluate the platform’s practicality, this dissertation presents a series of experiments on multiple IT systems that show negligible (statistically non-significant) performance impacts. To evaluate the platform’s efficacy, this research analyzes costs versus security benefits by quantifying the outcome (sizes of potential attack windows) in terms of the number of adaptations, and demonstrates that an IT system deployed and managed using the proposed MTD platform will increase attack difficulty.

3 pp. / Problems and pests of cacti, agave, and yuccas / Barrel cactus and Saguaro (Carnegiea gigantea) are easily transplanted. Procedures for safely and succesfully moving these plants are discussed in this bulletin.

Numerical simulations are presented for three dimensional viscous incompressible free shear flows. The numerical method is based on solving the vorticity equation using Vortex-In-Cell method. In this method, the vorticity field is discretized into a finite set of Lagrangian elements (particles) and the computational domain is covered by Eulerian mesh. Velocity field is computed on the mesh by solving Poisson equation. The solution proceeds in time by advecting the particles with the flow. Second order Adam-Bashford method is used for time integration. Exchange of information between Lagrangian particles and Eulerian grid is carried out using the M’4 interpolation scheme. The classical inviscid scheme is enhanced to account for stretching and viscous effects. For that matter, two schemes are used. The first one used periodic remeshing of the vortex particles along with fourth order finite difference approximation for the partial derivatives of the stretching and viscous terms. In the second scheme, derivatives are approximated by least squares polynomial. The novelty of this work is signified by using the moving least squares technique within the framework of the Vortex-in-Cell method and implementing it to a three dimensional temporal mixing layer. Comparisons of the mean flow and velocity statistics are made with experimental studies. The results confirm the validity of the present schemes. Both schemes also demonstrate capability to qualitatively capture significant flow scales, and allow gaining physical insight as to the development of instabilities and the formation of three dimensional vortex structures. The two schemes show acceptable low numerical diffusion as well.

Match moving är ett av de steg inom en vfx produktion som avgör och skapar intergrerandet mellan filmat material och filmiska effekter gjorda i 3D.  Redan under en inspelning förekommer förberedande arbete och dokumentation för att i ett senare stadie underlätta för match moving. Detta för att utesluta specifika problem som kan uppstå under match moving processen då det är väsentligt att skapandet av en virtuell kamera är korrekt i förhållande till det filmade materialet. Detta för att vfx ska kunna adderas senare. Detta arbete tar upp den problematik som kan uppstå när förberedelser och dokumentation saknas för det filmade materialet. Arbetet fokuserar på tester av olika arbetsmetoder för match moving samt analyser av det filmade materialet. Detta för att klargöra hur en vfx artist ska gå tillväga för att göra valet av arbetsmetod beroende på hur det filmade materialet ser ut. De arbetsmetoderna som tas upp i detta arbete är automatic tracking, tracking med enbart 2D feature points samt planar tracking och dess förberedande steg. Resultaten visar även på att olika arbetsmetoder ska behandlas på olika sätt av vfx artisten samt att de kan ha olika resultat beroende på hur det filmade materialet ser ut. Klargörandet av dessa arbetsmetoder och det filmade materialet med hjälp av tester gör valet av arbetsmetod simplare när det kommer till match moving. / Match moving is one of the steps within a vfx production pipeline that decides how filmed material and 3D effects will intergrate with each other. Already on set preparations and documentations are made to make the match moving process less problematic later in the pipeline. It is essential that the filmed material match the virtual created camera from the match moving process to make the intergration happen. This report discusses the problems that can arise when needed preparations on set are missing and how they can be solved by studying different methods for match moving. The report focuses on these methods compared to the filmed material and how a vfx artist can choose a method to work with depending on that material. The methods that are discussed in this report are automatic tracking, tracking with feature points only and planar tracking. The results also show that different methods should be treated differently from each other by the vfx artist and that the result can differ depending on how the filmed material looks. Clarifying these methods and filmed material with tests will make it easier to choose a method to work with while match moving.

Este trabalho tem por objetivo desenvolver ferramentas que permitam gerar em fones-de-ouvido o efeito psicoacústico de fontes sonoras locomovendo-se no espaço, por meio da auralização do sinal monofônico original. Embora a auralização binaural possa ser feita empregando variações de atraso (chamadas ITD interaural time difference, ou diferença de tempo interaural) e de intensidade (chamadas ILD interaural level difference, ou diferença de nível interaural) entre os canais, melhores resultados psicoacústicos podem ser obtidos ao se utilizar filtros digitais conhecidos como HRTFs (head related transfer functions, ou funções de transferência relativas à cabeça). Uma HRTF insere no sinal monofônico informações que possibilitam ao sistema auditivo identificá-lo como proveniente de uma direção específica, direção esta que é única para cada HRTF. Para posicionar uma fonte estática em uma direção específica, bastaria, então, filtrar o sinal original pela HRTF da direção desejada. Se, no entanto, for desejável que a fonte se locomova em uma trajetória contínua, um número infinitamente grande de filtros seria necessário. Como eles são, normalmente, obtidos empiricamente, um número arbitrariamente alto deles não está disponível. Disso surge a necessidade de técnicas de interpolação de HRTFs, que possibilitem gerar os filtros intermediários não disponíveis. Este trabalho apresenta três novas técnicas de interpolação de HRTFs, para assim alcançar o objetivo de auralizar fontes sonoras móveis: a interpolação triangular, que é uma técnica de interpolação linear baseada na técnica de panorama sonoro VBAP (vector-based amplitude panning, ou panorama sonoro baseado em vetores); o método das movimentações discretas, que busca explorar o limiar de percepção do nosso sistema auditivo para, com isso, gerar uma técnica extremamente barata computacionalmente; e a interpolação espectral, que altera continuamente as estruturas das HRTFs para gerar filtros interpolados. São apresentadas também as implementações feitas dessas novas técnicas desenvolvidas, bem como os testes numéricos realizados para medir sua eficácia. / The goal of this work is the development of tools that allow simulating through headphones the psychoacoustic effect of sound sources moving in space, by the auralisation of the original monophonic signals. Although binaural auralisation can be implemented using variations in delays (called ITD interaural time difference) and in intensities (called ILD interaural level difference) among channels, better psychoacoustic results can be achieved using digital filters known as HRTFs (head related transfer functions). A HRTF inserts in the monophonic signal information that allow the auditory system to perceive this signal to be as if coming from a specific direction, which is unique for each single HRTF. Thus, to position a static sound source at a specific direction, filtering the original signal with the HRTF from the desired direction would be enough. Nevertheless, if it is desired that the sound source moves in a continuous trajectory, an infinitely large amount of filters would be necessary. Since they are usually obtained by measurements, such an arbitrarily large amount of them is not available. In this case, HRTF interpolation techniques that generate intermediary filters must be used. This work presents three new HRTF interpolation techniques in order to auralise moving sound sources: the triangular interpolation, a linear interpolation technique based on the VBAP amplitude panning technique; the discrete movements method, an extremely efficient technique that exploits the auditory systems limitations in perceiving very small changes in direction; and the spectral interpolation, that alters continuously the structures of the HRTFs to generate interpolated filters. Implementations of these techniques are discussed and numerical tests are also presented.

This thesis considers one-dimensional moving mesh (MM) methods coupled with semi-Lagrangian (SL) discretisations of partial differential equations (PDEs) for meteorological applications. We analyse a semi-Lagrangian numerical solution to the viscous Burgers’ equation when using linear interpolation. This gives expressions for the phase and shape errors of travelling wave solutions which decay slowly with increasing spatial and temporal resolution. These results are verified numerically and demonstrate qualitative agreement for high order interpolants. The semi-Lagrangian discretisation is coupled with a 1D moving mesh, resulting in a moving mesh semi-Lagrangian (MMSL) method. This is compared against two moving mesh Eulerian methods, a two-step remeshing approach, solved with the theta-method, and a coupled moving mesh PDE approach, which is solved using the MATLAB solver ODE45. At each time step of the SL method, the mesh is updated using a curvature based monitor function in order to reduce the interpolation error, and hence numerical viscosity. This MMSL method exhibits good stability properties, and captures the shape and speed of the travelling wave well. A meteorologically based 1D vertical column model is described with its SL solution procedure. Some potential benefits of adaptivity are demonstrated, with static meshes adapted to initial conditions. A moisture species is introduced into the model, although the effects are limited.

This master thesis is covering the modeling of the melting process in a tank filled with AdBlue. Due to AdBlue freezing at temperatures below -11 degree there is a need to add heat to be able to secure dosing in all situations. A rig for simulating freezing conditions is created with the possibility to store AdBlue in temperatures down to -40 degree. Temperatures are measured in and around the tank containing AdBlue and in the equipment used for adding heat. Two models are created from physical relations to estimate the mass of AdBlue melted, a static temperature model and a dynamic temperature model. The static model shows good results when calibrated at this specific setup and is very easy to use. The dynamic temperature model is more advanced but describes the real physical system better without external calibration.

This thesis examines the interconnected relationship that exists between sound and moving-image in the music-video. The flow of images used in many music videos often carries no definite meaning. Rather, the viewer must perceive the physiological sensations of the video's audiovisual expression to make sense of it. Thus, both the expression and the perception of music-video is a cross-modal process. Using Vivian Sobchack's theory of cinesthetics as a framework, the thesis contends that the music-video produces an aural visuality in which sound can be cinesthetically expressed and perceived as image and the image perceived and expressed as sound.