Autonomous Navigation and Mapping using Monocular Low-Resolution Grayscale Vision

Vision has been a powerful tool for navigation of intelligent and man-made systems ever since the cybernetics revolution in the 1970s. There have been two basic approaches to the navigation of computer controlled systems: The self-contained bottom-up development of sensorimotor abilities, namely perception and mobility, and the top-down approach, namely artificial intelligence, reasoning and knowledge based methods. The three-fold goal of autonomous exploration, mapping and localization of a mobile robot however, needs to be developed within a single framework. An algorithm is proposed to answer the challenges of autonomous corridor navigation and mapping by a mobile robot equipped with a single forward-facing camera. Using a combination of corridor ceiling lights, visual homing, and entropy, the robot is able to perform straight line navigation down the center of an unknown corridor. Turning at the end of a corridor is accomplished using Jeffrey divergence and time-to-collision, while deflection from dead ends and blank walls uses a scalar entropy measure of the entire image. When combined, these metrics allow the robot to navigate in both textured and untextured environments. The robot can autonomously explore an unknown indoor environment, recovering from difficult situations like corners, blank walls, and initial heading toward a wall. While exploring, the algorithm constructs a Voronoi-based topo-geometric map with nodes representing distinctive places like doors, water fountains, and other corridors. Because the algorithm is based entirely upon low-resolution (32 x 24) grayscale images, processing occurs at over 1000 frames per second

The Main Belt Comets and ice in the Solar System

We review the evidence for buried ice in the asteroid belt; specifically the questions around the so-called Main Belt Comets (MBCs). We summarise the evidence for water throughout the Solar System, and describe the various methods for detecting it, including remote sensing from ultraviolet to radio wavelengths. We review progress in the first decade of study of MBCs, including observations, modelling of ice survival, and discussion on their origins. We then look at which methods will likely be most effective for further progress, including the key challenge of direct detection of (escaping) water in these bodies

Papers presented to the Conference on Large Body Impacts and Terrestrial Evolution: Geological, Climatological, and Biological Implications

The effects of large impacts on the environment are discussed and include thermal effects, atmospheric effects, changes in ocean temperatures, and geomagnetic anomalies. Biological factors such as extinction and increases in mutation development were investigated. Geological anomalies studied include stratigraphic gaps, extinction of entire boundary layers from the geological record, and geochemical oddities. Evidence was examined for impact cratering throughout the world

Fluid consistencies. Material relationality in human engagements with water

Material things are not just passive recipients of human categories, meanings and values, nor mere subjects of human agency. Their particular characteristics and behaviours are formative of human–non-human relations. The common material properties of things, and the shared cognitive and phenomenological processes through which people interact with them, generate recurrent ideas and patterns of engagement in diverse cultural and historical contexts. Despite growing instrumentalism in human ‘management’ of the material world, and the emergence of new relational forms, these patterns persist

Virtue and self-interest

Why be moral? One possible, and compelling answer is that to act morally is in an agent's self-interest. Such an answer can be either elevationist (broadly speaking the Aristotelian/Platonic approach) where self-interest is elevated to coincide with living the good life, or reductionist where morality is defined as acting in an agent's self-interest. Elevationist moral theories appear flawed. If you are in possession of information that, if divulged, will bring about the deaths of others then it may be virtuous to stay silent. However, if staying silent results in you being slowly tortured to death in an effort to extract the information then it seems bizarre to suggest that in doing so you are flourishing, happy, or acting out of self-interest. Reductionist moral theories, acting for the 'good of self' rather than the 'good of others', are widely considered to be the antithesis of morality. Moral philosophers tend to attack such positions claiming that the doctrine of egoism is unworkable. It is commonly claimed that any theory which recommends 'an agent do x if x is in the agent's best interest' is inconsistent, incoherent, or contradictory and fails to meet the basic requirements of a moral theory (notably the requirement of universalisability). I begin this thesis with an examination of ethical egoism in its most widely known consequentialist form; i.e. an agent ought to act so as to bring about the best consequences for that agent. I examine the major criticisms of this theory and demonstrate that the axioms of egoism can be developed so as to overcome these criticisms. I argue that consequentialist based ethical egoism is coherent, consistent and noncontradictory. However, I go on to argue that while egoism can be formulated in a manner that overcomes all the aforementioned analytic criticisms it is a flawed moral theory in that within certain contexts the action deemed morally correct by egoism is, as a matter of fact, morally pernicious. That a theory contains a flaw is not reason enough to discard the entire theory and I go on to contend that the problem with egoism is the consequentialist approach, not the fact that it is based on self-interest. In Part 2 of the thesis I abandon the consequentialist approach and examine the possibility of a flourishing-based form of ethical egoism. I further develop the axioms of egoism established in Part 1 through an examination of the concept of flourishing (as commonly associated with virtue ethics). Ultimately I tread a path between the consequentialist and elevationist positions. While I do not elevate self-interest to acting virtuously I do contend that an egoist must adopt certain virtues if that egoist is to have the best possibility to flourish. However, I further contend that an egoist ought to act so as to promote that which the egoist values and that this agent-relative hierarchy of values, which necessarily contains certain virtues, determines the manner in which an egoist ought to act

Sensor system and related models to determine irregular shaped 3-D objects

This work comprises several parts, the initial part o f which is a review o f the techniques in use at present for measuring shape and characterising products. The major work details a ring sensor system, which consists o f a large number o f transmitters and receivers alternately arranged on the circumference o f a metal annulus. Using a modified polar co-ordinate system and trigonometric functions, two enveloping spirals o f an object can be determined. One or both spirals can then be used for further data analysis. Each spiral consists o f intersections between enveloping chords and parts o f the chords. The area surrounding the object is segmented and properties such as volume and axis measurements can be determined. A mode! was developed to simulate artificial objects o f various shapes. Simulation tests were carried out to determine the limits o f the system concerning position within the ring, shape and speed o f the object and resolution o f the ring. A ring was manufactured for actual tests, which were carried out mainly on potatoes to confirm the possible use in practice and to show the relative merits compared with existing systems. Interesting side issues are introduced, such as the low number of primary data, possibilities of further reduction using differential coding, and the consumption time of the algorithms. Finally, a model for the simulation o f more than one object in the ring at the same time is introduced and a possible way o f separation is investigated

Yearbook of the Maimonides Centre for Advanced Studies. 2019

The Yearbook of the Maimonides Centre for Advanced Studies mirrors the annual activities of staff and visiting fellows of the Centre as well as scholars of the Institute for Jewish Philosophy and Religion at the University of Hamburg and reports on symposia, workshops, and lectures. Although aimed at a wider audience, the yearbook also contains academic articles and book reviews on scepticism in Judaism and scepticism in general

Yearbook of the Maimonides Centre for Advanced Studies 2019

The Yearbook of the Maimonides Centre for Advanced Studies mirrors the annual activities of visiting fellows, staff, and affiliates of the Maimonides Centre of Advanced Studies - Jewish Scepticism, Universität Hamburg. Its main section contains scholarly articles about Judaism and scepticism, both individually and together, among different thinkers and within different areas of study. Each volume of the Yearbook also includes a section with an overview of the activities and events conducted at MCAS during a given academic year, as well as a report on its library

Hyperspectral Imaging for Fine to Medium Scale Applications in Environmental Sciences

The aim of the Special Issue “Hyperspectral Imaging for Fine to Medium Scale Applications in Environmental Sciences” was to present a selection of innovative studies using hyperspectral imaging (HSI) in different thematic fields. This intention reflects the technical developments in the last three decades, which have brought the capacity of HSI to provide spectrally, spatially and temporally detailed data, favoured by e.g., hyperspectral snapshot technologies, miniaturized hyperspectral sensors and hyperspectral microscopy imaging. The present book comprises a suite of papers in various fields of environmental sciences—geology/mineral exploration, digital soil mapping, mapping and characterization of vegetation, and sensing of water bodies (including under-ice and underwater applications). In addition, there are two rather methodically/technically-oriented contributions dealing with the optimized processing of UAV data and on the design and test of a multi-channel optical receiver for ground-based applications. All in all, this compilation documents that HSI is a multi-faceted research topic and will remain so in the future