Wind-energy based path planning for electric unmanned aerial vehicles using Markov Decision Processes

Exploiting wind-energy is one possible way to ex- tend flight duration for Unmanned Arial Vehicles. Wind-energy can also be used to minimise energy consumption for a planned path. In this paper, we consider uncertain time-varying wind fields and plan a path through them. A Gaussian distribution is used to determine uncertainty in the Time-varying wind fields. We use Markov Decision Process to plan a path based upon the uncertainty of Gaussian distribution. Simulation results that compare the direct line of flight between start and target point and our planned path for energy consumption and time of travel are presented. The result is a robust path using the most visited cell while sampling the Gaussian distribution of the wind field in each cell.

The creative cities discourse : production and/or consumption?

The already considerable debate about what constitutes a 'creative' city becomes ever more critical as the world urbanizes at a rapid pace. In this chapter the author argues that the key tensions in discussions over what makes cities more conducive to and supportive of creativity revolve around perspectives that are either production-centric or consumption-centric. Scholars are increasing prepared to claim priority for the city-region over the nation-state as an economic and cultural agent in the contemporary world, but are they ready to deal with major changes in the nature of cultural production and consumption themselves? A number of examples of new challenges for the creative cities 'discourse' rounds out the chapter.

Rotorcraft collision avoidance using spherical image-based visual servoing and single point features

This paper presents a reactive collision avoidance method for small unmanned rotorcraft using spherical image-based visual servoing. Only a single point feature is used to guide the aircraft in a safe spiral like trajectory around the target, whilst a spherical camera model ensures the target always remains visible. A decision strategy to stop the avoidance control is derived based on the properties of spiral like motion, and the effect of accurate range measurements on the control scheme is discussed. We show that using a poor range estimate does not significantly degrade the collision avoidance performance, thus relaxing the need for accurate range measurements. We present simulated and experimental results using a small quad rotor to validate the approach.

Detecting conversing groups of chatters : a model, algorithms, and tests

Chatrooms, for example Internet Relay Chat, are generally multi-user, multi-channel and multiserver chat-systems which run over the Internet and provide a protocol for real-time text-based conferencing between users all over the world. While a well-trained human observer is able to understand who is chatting with whom, there are no efficient and accurate automated tools to determine the groups of users conversing with each other. A precursor to analysing evolving cyber-social phenomena is to first determine what the conversations are and which groups of chatters are involved in each conversation. We consider this problem in this paper. We propose an algorithm to discover all groups of users that are engaged in conversation. Our algorithms are based on a statistical model of a chatroom that is founded on our experience with real chatrooms. Our approach does not require any semantic analysis of the conversations, rather it is based purely on the statistical information contained in the sequence of posts. We improve the accuracy by applying some graph algorithms to clean the statistical information. We present some experimental results which indicate that one can automatically determine the conversing groups in a chatroom, purely on the basis of statistical analysis.

Motion planning and stochastic control with experimental validation on a planetary rover

Motion planning for planetary rovers must consider control uncertainty in order to maintain the safety of the platform during navigation. Modelling such control uncertainty is difficult due to the complex interaction between the platform and its environment. In this paper, we propose a motion planning approach whereby the outcome of control actions is learned from experience and represented statistically using a Gaussian process regression model. This model is used to construct a control policy for navigation to a goal region in a terrain map built using an on-board RGB-D camera. The terrain includes flat ground, small rocks, and non-traversable rocks. We report the results of 200 simulated and 35 experimental trials that validate the approach and demonstrate the value of considering control uncertainty in maintaining platform safety.

BIM-based lifecycle planning and specifications for sustainable cities of the future: A conceptual approach

Annually, several million tonnes of waste are produced from reworks, demolition, and use of substandard materials. Building Information Modelling (BIM), a digital representation of facilities and their constituent data, is a viable means of addressing some concerns about the impacts of these processes. BIM functionalities can be extended and combined with rich building information from specifications and product libraries, for efficient, streamlined design and construction. This paper conceptualises a framework for BIM-knowledge transfer from advanced economies for adaptation and use in urban development works in developing nations using the Sydney Down Under and Lagos Eko Atlantic projects as reference points. We present a scenario that highlights BIM-based lifecycle planning/specifications as agents of sustainable construction (in terms of cost and time) crucial to the quality of as-built data from early on in city development. We show how, through the use of BIM, city planners in developing nations can avoid high, retrospective (and sometimes wasteful) maintenance costs and leapfrog infrastructure management standards of advanced economies. Finally, this paper illustrates how BIM can address concerns about economic sustainability during city development in developing countries by enriching model objects with specification information sourced from a product library.

Precarious Creativity: Global Media, Local Labor

Precarious Creativity examines the seismic changes confronting media workers in an age of globalization and corporate conglomeration. This pathbreaking anthology peeks behind the hype and supposed glamor of screen media industries to reveal the intensifying pressures and challenges confronting actors, editors, electricians, and others. The authors take on pressing conceptual and methodological issues while also providing insightful case studies of workplace dynamics regarding creativity, collaboration, exploitation, and cultural difference. Furthermore, it examines working conditions and organizing efforts on all six continents, offering broad-ranging and comprehensive analysis of contemporary screen media labor in such places as Lagos, Prague, Hollywood, and Hyderabad. The collection also examines labor conditions across a range of job categories that includes, for example, visual effects, production services, and adult entertainment. With contributions from such leading scholars as John Caldwell, Vicki Mayer, Herman Gray, and Tejaswini Ganti, Precarious Creativity offers timely critiques of media globalization while also intervening in broader debates about labor, creativity, and precarity.

Indigenous cultural landscapes: Equitably defining the 'authenticity' of the intangible

Over hundreds of generations, indigenous groups around the world have passed down their traditional landscape associations, a number of which are intangible and therefore unquantifiable. Yet, these associative relationships with nature have been, and continue to be, pivotal in cultural evolution. Determining the authenticity of intangible landscape associations has caused much controversy, and in recent decades, indigenous groups have begun seeking protection of their places of significance. In response, the United Nations Educational, Scientific and Cultural Organisation (UNESCO) World Heritage Committee (WHC) developed a criterion that intended to assist in the identification and protection of cultural landscapes. The WHC has therefore become the global authority responsible for determining the authenticity of cultural landscapes, including those with intangible associations rather than material cultural evidence. However, even with the support of the United Nations, UNESCO and the WHC, it is unlikely that every tangible cultural landscape will be sufficiently recognised and protected. Therefore, this research paper explores the effectiveness of current approaches to gauging authenticity in instances where multiple landscapes are valued according to similar characteristics. Further, this work studies the inherent relationship between the indigenous Maori population of the South Island of New Zealand, in particular Kai Tahi peoples, and their significant landscape features, as a means of considering the breadth and depth of historic intangible associations. In light of these findings, this research challenges the appropriateness of the term 'authenticity' when analysing not only the subjective, but more pressingly, the intangible. It therefore questions the role of empirical data in demonstrating authenticity, while recognising that a prolific list of such intangible cultural landscapes has the potential to diminish integrity. This, this paper addresses an urgent need for increased social research in this area, namely in identifying cultural landscape protection methods that empower all local indigenous communities, not just those which are the most critically acclaimed.