Gathering on Rings for Myopic Asynchronous Robots With Lights

We investigate gathering algorithms for asynchronous autonomous mobile robots moving in uniform ring-shaped networks. Different from most work using the Look-Compute-Move (LCM) model, we assume that robots have limited visibility and lights. That is, robots can observe nodes only within a certain fixed distance, and emit a color from a set of constant number of colors. We consider gathering algorithms depending on two parameters related to the initial configuration: M_{init}, which denotes the number of nodes between two border nodes, and O_{init}, which denotes the number of nodes hosting robots between two border nodes. In both cases, a border node is a node hosting one or more robots that cannot see other robots on at least one side. Our main contribution is to prove that, if M_{init} or O_{init} is odd, gathering is always feasible with three or four colors. The proposed algorithms do not require additional assumptions, such as knowledge of the number of robots, multiplicity detection capabilities, or the assumption of towerless initial configurations. These results demonstrate the power of lights to achieve gathering of robots with limited visibility

Asynchronous Gathering in a Torus

We consider the gathering problem for asynchronous and oblivious robots that cannot communicate explicitly with each other but are endowed with visibility sensors that allow them to see the positions of the other robots. Most investigations on the gathering problem on the discrete universe are done on ring shaped networks due to the number of symmetric configurations. We extend in this paper the study of the gathering problem on torus shaped networks assuming robots endowed with local weak multiplicity detection. That is, robots cannot make the difference between nodes occupied by only one robot from those occupied by more than one robot unless it is their current node. Consequently, solutions based on creating a single multiplicity node as a landmark for the gathering cannot be used. We present in this paper a deterministic algorithm that solves the gathering problem starting from any rigid configuration on an asymmetric unoriented torus shaped network

Rendezvous on a Known Dynamic Point on a Finite Unoriented Grid

In this paper, we have considered two fully synchronous $\mathcal{OBLOT}$ robots having no agreement on coordinates entering a finite unoriented grid through a door vertex at a corner, one by one. There is a resource that can move around the grid synchronously with the robots until it gets co-located along with at least one robot. Assuming the robots can see and identify the resource, we consider the problem where the robots must meet at the location of this dynamic resource within finite rounds. We name this problem "Rendezvous on a Known Dynamic Point". Here, we have provided an algorithm for the two robots to gather at the location of the dynamic resource. We have also provided a lower bound on time for this problem and showed that with certain assumption on the waiting time of the resource on a single vertex, the algorithm provided is time optimal. We have also shown that it is impossible to solve this problem if the scheduler considered is semi-synchronous

Practical Considerations and Applications for Autonomous Robot Swarms

In recent years, the study of autonomous entities such as unmanned vehicles has begun to revolutionize both military and civilian devices. One important research focus of autonomous entities has been coordination problems for autonomous robot swarms. Traditionally, robot models are used for algorithms that account for the minimum specifications needed to operate the swarm. However, these theoretical models also gloss over important practical details. Some of these details, such as time, have been considered before (as epochs of execution). In this dissertation, we examine these details in the context of several problems and introduce new performance measures to capture practical details. Specifically, we introduce three new metrics: (1) the distance complexity (reflecting power usage and wear-and-tear of robots), (2) the spatial complexity (reflecting the space needed for the algorithm to work), and (3) local computational complexity (reflecting the computational requirements for each robot in the swarm). We apply these metrics in the study of some well-known and important problems, such as Complete Visibility and Arbitrary Pattern Formation. We also introduce and study a new problem, Doorway Egress, that captures the essence of a swarm’s navigation through restricted spaces. First, we examine the distance and spatial complexity used across a class of Complete Visibility algorithms. Second, we provide algorithms for Complete Visibility on an integer plane, including some that are asymptotically optimal in terms of time, distance complexity, and spatial complexity. Third, we introduce the problem of Doorway Egress and provide algorithms for a variety of robot swarm models with various optimalities. Finally, we provide an optimal algorithm for Arbitrary Pattern Formation on the grid

Cinema and commercial space tourism:The politics of escapism

Space tourism has been one of the most enduring tropes in the cinema from the early 1900s until the present day, yet there exists no systematic, comprehensive investigation situating these widely diversified depictions of space tourism within a broader historical context of technological innovation and associated social transformation. The contemporary social climate, whereby commercial space tourism is an emergent possibility, calls for the decolonisation of the term ‘tourism’ and its categorical associations, in order to assess how visions of space tourism within cinematic, science-fiction futures project the history of tourism and its detrimental environmental, commercial, and colonial implications. The written portion of the dissertation uses close-textual-analysis and discursive transcoding as the primary methodologies to identify and investigate five unique trends in the thematic representation of cinematic space tourism, each linked to a distinct ‘moment’ of widespread crisis and transformation. Ultimately, this will contribute to a broader understanding concerning how science-fiction explores social constructions of race, class, and gender. As a practice-based accompaniment to these critical discussions, I relay my findings in a space film which compiles knowledge drawn from film and literature scholarship, as well as from the analysis of the selected case studie

Special oils for halal and safe cosmetics

Three types of non conventional oils were extracted, analyzed and tested for toxicity. Date palm kernel oil (DPKO), mango kernel oil (MKO) and Ramputan seed oil (RSO). Oil content for tow cultivars of dates Deglect Noor and Moshkan was 9.67% and 7.30%, respectively. The three varieties of mango were found to contain about 10% oil in average. The red yellow types of Ramputan were found to have 11 and 14% oil, respectively. The phenolic compounds in DPKO, MKO and RSO were 0.98, 0.88 and 0.78 mg/ml Gallic acid equivalent, respectively. Oils were analyzed for their fatty acid composition and they are rich in oleic acid C18:1 and showed the presence of (dodecanoic acid) lauric acid C12:0, which reported to appear some antimicrobial activities. All extracted oils, DPKO, MKO and RSO showed no toxic effect using prime shrimp bioassay. Since these oils are stable, melt at skin temperature, have good lubricity and are great source of essential fatty acids; they could be used as highly moisturizing, cleansing and nourishing oils because of high oleic acid content. They are ideal for use in such halal cosmetics such as Science, Engineering and Technology 75 skin care and massage, hair-care, soap and shampoo products

Crit-i-kit (playing cards and raw list)

Crit-i-kit is a game that explores the tools, equipment and supplies that are considered ‘essential’ to the inhabitation of landscape. Walkers encountered by the artist in a variety of environments anonymously shared the complete contents of the bags they were carrying at the time; items were then catalogued and grouped into broad thematic categories. Each category is printed onto a card that is then randomly selected by a player and used to guide a new walk. This work prompts consideration of the structures we individually build and respond to as we walk within the world. Each item is proposed as a structure that guides our inhabitation; a vessel for carrying, a gesture of care, or an item of potential are each thought of as prompts for spontaneous architectures that result in profoundly different modes of liv-ing

Lineages and Advancements in Material Culture Studies

This volume comprises a curated conversation between members of the Material Culture Section of University College London Anthropology. In laying out the state of play in the field, it challenges how the anthropology of material culture is being done and argues for new directions of enquiry and new methods of investigation. The contributors consider the ramifications of specific research methods and explore new methodological frameworks to address areas of human experience that require a new analytical approach. The case studies draw from a range of contexts, including digital objects, infrastructure, data, extraterrestriality, ethnographic curation, and medical materiality. They include timely reappraisals of now-classical analytical models that have shaped the way we understand the object, the discipline, knowledge formation, and the artefact