5,785 research outputs found

    Catgame: A Tool For Problem Solving In Complex Dynamic Systems Using Game Theoretic Knowledge Distribution In Cultural Algorithms, And Its Application (catneuro) To The Deep Learning Of Game Controller

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    Cultural Algorithms (CA) are knowledge-intensive, population-based stochastic optimization methods that are modeled after human cultures and are suited to solving problems in complex environments. The CA Belief Space stores knowledge harvested from prior generations and re-distributes it to future generations via a knowledge distribution (KD) mechanism. Each of the population individuals is then guided through the search space via the associated knowledge. Previously, CA implementations have used only competitive KD mechanisms that have performed well for problems embedded in static environments. Relatively recently, CA research has evolved to encompass dynamic problem environments. Given increasing environmental complexity, a natural question arises about whether KD mechanisms that also incorporate cooperation can perform better in such environments than purely competitive ones? Borrowing from game theory, game-based KD mechanisms are implemented and tested against the default competitive mechanism – Weighted Majority (WTD). Two different concepts of complexity are addressed – numerical optimization under dynamic environments and hierarchal, multi-objective optimization for evolving deep learning models. The former is addressed with the CATGame software system and the later with CATNeuro. CATGame implements three types of games that span both cooperation and competition for knowledge distribution, namely: Iterated Prisoner\u27s Dilemma (IPD), Stag-Hunt and Stackelberg. The performance of the three game mechanisms is compared with the aid of a dynamic problem generator called Cones World. Weighted Majority, aka “wisdom of the crowd”, the default CA competitive KD mechanism is used as the benchmark. It is shown that games that support both cooperation and competition do indeed perform better but not in all cases. The results shed light on what kinds of games are suited to problem solving in complex, dynamic environments. Specifically, games that balance exploration and exploitation using the local signal of ‘social’ rank – Stag-Hunt and IPD – perform better. Stag-Hunt which is also the most cooperative of the games tested, performed the best overall. Dynamic analysis of the ‘social’ aspects of the CA test runs shows that Stag-Hunt allocates compute resources more consistently than the others in response to environmental complexity changes. Stackelberg where the allocation decisions are centralized, like in a centrally planned economic system, is found to be the least adaptive. CATNeuro is for solving neural architecture search (NAS) problems. Contemporary ‘deep learning’ neural network models are proven effective. However, the network topologies may be complex and not immediately obvious for the problem at hand. This has given rise to the secondary field of neural architecture search. It is still nascent with many frameworks and approaches now becoming available. This paper describes a NAS method based on graph evolution pioneered by NEAT (Neuroevolution of Augmenting Topologies) but driven by the evolutionary mechanisms under Cultural Algorithms. Here CATNeuro is applied to find optimal network topologies to play a 2D fighting game called FightingICE (derived from “The Rumble Fish” video game). A policy-based, reinforcement learning method is used to create the training data for network optimization. CATNeuro is still evolving. To inform the development of CATNeuro, in this primary foray into NAS, we contrast the performance of CATNeuro with two different knowledge distribution mechanisms – the stalwart Weighted Majority and a new one based on the Stag-Hunt game from evolutionary game theory that performed the best in CATGame. The research shows that Stag-Hunt has a distinct edge over WTD in terms of game performance, model accuracy, and model size. It is therefore deemed to be the preferred mechanism for complex, hierarchical optimization tasks such as NAS and is planned to be used as the default KD mechanism in CATNeuro going forward

    Nonterrestrial utilization of materials: Automated space manufacturing facility

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    Four areas related to the nonterrestrial use of materials are included: (1) material resources needed for feedstock in an orbital manufacturing facility, (2) required initial components of a nonterrestrial manufacturing facility, (3) growth and productive capability of such a facility, and (4) automation and robotics requirements of the facility

    Source-tracking cadmium in New Zealand agricultural soils: a stable isotope approach

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    Cadmium (Cd) is a toxic heavy metal, which is accumulated by plants and animals and therefore enters the human food chain. In New Zealand (NZ), where Cd mainly originates from the application of phosphate fertilisers, stable isotopes can be used to trace the fate of Cd in soils and potentially the wider environment due to the limited number of sources in this setting. Prior to 1997, extraneous Cd added to soils in P fertilisers was essentially limited to a single source, the small pacific island of Nauru. Analysis of Cd isotope ratios (ɛ114/110Cd) in Nauru rock phosphate, pre-1997 superphosphate fertilisers, and Canterbury (Lismore Stony Silt Loam) topsoils (Winchmore Research Farm) has demonstrated their close similarity with respect to ɛ114/110Cd. We report a consistent ɛ114/110Cd signature in fertiliser-derived Cd throughout the latter twentieth century. This finding is useful because it allows the application of mixing models to determine the proportions of fertiliser-derived Cd in the wider environment. We believe this approach has good potential because we also found the ɛ114/110Cd in fertilisers to be distinct from unfertilised Canterbury subsoils. In our analysis of the Winchmore topsoil series (1949-2015), the ɛ114/110Cd remained quite constant following the change from Nauru to other rock phosphate sources in 1997, despite a corresponding shift in fertiliser ɛ114/110Cd at this time. We can conclude that to the present day, the Cd in topsoil at Winchmore still mainly originates from historical phosphate fertilisers. One implication of this finding is that the current applications of P fertiliser are not resulting in further Cd accumulation. We aim to continue our research into Cd fate, mobility and transformations in the NZ environment by applying Cd isotopes in soils and aquatic environments across the country

    Energy Management Systems for Smart Electric Railway Networks: A Methodological Review

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    Energy shortage is one of the major concerns in today’s world. As a consumer of electrical energy, the electric railway system (ERS), due to trains, stations, and commercial users, intakes an enormous amount of electricity. Increasing greenhouse gases (GHG) and CO2 emissions, in addition, have drawn the regard of world leaders as among the most dangerous threats at present; based on research in this field, the transportation sector contributes significantly to this pollution. Railway Energy Management Systems (REMS) are a modern green solution that not only tackle these problems but also, by implementing REMS, electricity can be sold to the grid market. Researchers have been trying to reduce the daily operational costs of smart railway stations, mitigating power quality issues, considering the traction uncertainties and stochastic behavior of Renewable Energy Resources (RERs) and Energy Storage Systems (ESSs), which has a significant impact on total operational cost. In this context, the first main objective of this article is to take a comprehensive review of the literature on REMS and examine closely all the works that have been carried out in this area, and also the REMS architecture and configurations are clarified as well. The secondary objective of this article is to analyze both traditional and modern methods utilized in REMS and conduct a thorough comparison of them. In order to provide a comprehensive analysis in this field, over 120 publications have been compiled, listed, and categorized. The study highlights the potential of leveraging RERs for cost reduction and sustainability. Evaluating factors including speed, simplicity, efficiency, accuracy, and ability to handle stochastic behavior and constraints, the strengths and limitations of each optimization method are elucidated

    Creative Collaborative Circular Economics, Exponential System Design for Sustainability in Fashion Design

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    Associação com Universidade do Minho | Escola de Engenhariaapproaches and contributions from design to sustainability aiming to raise responsiveness and awareness among fashion design students and local communities about the conscious and sustainable production and consumption of fashion product". This thesis fits in the area of design, especially in the applicability of the multidisciplinary way of thinking, creativity, empathy and experimentation that is part of the design thinking methodology with the consumer as the starting point and centre of attention, and its interrelations with social innovation, environmental sustainability, fashion design considering the entire life cycle of products, services and systems. Undergraduate and Master of Fashion Design students at the University of Beira Interior develop collection projects and the (coordinated) clothes are kept in a closed warehouse, only eventually attending some events. Thus, the following opportunities were perceived: (i) Environmental Dimension: Promote a better designation and destination for these clothes; (ii) Collaborative Economy: Reuse through a new P2P business model; (iii) Social innovation: Sensitize and make society aware of new business models, contributing to and increasing the importance of the designer in the way of thinking and seeking creative solutions to social and environmental problems. What could one do with these practically stored clothes without public accessibility? Here are the reasons for a proposal to implement a new business model in Covilhã, Portugal. This thesis proposes the business model “Exponential System Design for Sustainability in Fashion” that can be called Exponential since it is scalable and modular, collaborative and sustainable services in fashion products. It may be replicable in its entirety, or in parts, in other places and contexts, adopting modularity as an adaptive resource. Initially identifies whether the perceived barriers to traditional Portuguese consumer behavior. But, for the new generation is a matter of awareness, as Portugal is also receiving influences from other cultures. Accelerating sustainable development requires a paradigm shift in terms of the production process in order to migrate from a linear to a circular economy. This comprises changing habits, mindsets and methods rooted in society. So far in terms of territorial innovation, there is no knowledge of business models that replace access property with the stated characteristics.objetivo geral da tese consiste em “sistematizar um modelo integrador com abordagens e contribuições do design para a sustentabilidade visando promover a sensibilização e conscientização dos estudantes de design de moda e das comunidades locais, sobre a produção e o consumo consciente e sustentável do produto de moda”. Esta tese insere-se na área do design, especialmente na aplicabilidade do modo de pensar multidisciplinar, criatividade, empatia e experimentação que faz parte da metodologia design thinking tendo o consumidor como ponto de partida e centro de atenção, e nas suas inter-relações com a inovação social, sustentabilidade ambiental, design de moda considerando todo o ciclo de vida de produtos, serviços e sistemas. Os alunos da licenciatura e do mestrado em Design de Moda na Universidade da Beira Interior desenvolvem projetos de coleção e as roupas (coordenados) ficam guardadas num armazém fechado, vindo só eventualmente a participarem em alguns eventos. Assim, percebeu-se as seguintes oportunidades: (i) Dimensão Ambiental: Promover uma melhor designação e destinação para essas roupas; (ii) Economia colaborativa: Reutilização através de novo modelo de negócio P2P; (iii) Inovação social: Sensibilizar e conscientizar a sociedade para novos modelos de negócio vindo a contribuir e ampliar a importância do designer no modo de pensar e de buscar soluções criativa para os problemas socioambiental. O que se poderia fazer com estas roupas praticamente armazenadas sem a apreciação do público? Eis aí as razões para uma proposta de implantação de um novo modelo de negócio em Covilhã, Portugal. Esta tese propõe o modelo de negócio “Design de Sistema Exponencial para a Sustentabilidade na Moda” chamamos de Exponencial por ser escalável e modular, com prestação de serviços eco-eficientes, colaborativos e sustentáveis em produtos de moda. Ele poderá ser replicável na sua totalidade, ou por partes, em outros lugares e contextos, adotando-se, para isso, a modularidade como recurso adaptativo. Inicialmente identifica se as barreiras percebidas ao comportamento do consumidor português tradicional. Porém na nova geração é uma questão de conscientização, Portugal também está a receber influências de outras culturas. Acelerar o desenvolvimento sustentável requer uma mudança do paradigma em termos do processo produtivo, a fim de migrar de uma economia linear para uma economia circular. Trata-se de mudar hábitos, mentalidades e métodos enraizados na sociedade. Até o momento em termos de inovação territorial não há conhecimento de modelos de negócios que substituam a propriedade de acesso com estas características

    Path planning algorithms for atmospheric science applications of autonomous aircraft systems

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    Among current techniques, used to assist the modelling of atmospheric processes, is an approach involving the balloon or aircraft launching of radiosondes, which travel along uncontrolled trajectories dependent on wind speed. Radiosondes are launched daily from numerous worldwide locations and the data collected is integral to numerical weather prediction.This thesis proposes an unmanned air system for atmospheric research, consisting of multiple, balloon-launched, autonomous gliders. The trajectories of the gliders are optimised for the uniform sampling of a volume of airspace and the efficient mapping of a particular physical or chemical measure. To accomplish this we have developed a series of algorithms for path planning, driven by the dual objectives of uncertainty andinformation gain.Algorithms for centralised, discrete path planning, a centralised, continuous planner and finally a decentralised, real-time, asynchronous planner are presented. The continuous heuristics search a look-up table of plausible manoeuvres generated by way of an offline flight dynamics model, ensuring that the optimised trajectories are flyable. Further to this, a greedy heuristic for path growth is introduced alongside a control for search coarseness, establishing a sliding control for the level of allowed global exploration, local exploitation and computational complexity. The algorithm is also integrated with a flight dynamics model, and communications and flight systems hardware, enabling software and hardware-in-the-loop simulations. The algorithm outperforms random search in two and three dimensions. We also assess the applicability of the unmanned air system in ‘real’ environments, accounting for the presence of complicated flow fields and boundaries. A case study based on the island South Georgia is presented and indicates good algorithm performance in strong, variable winds. We also examine the impact of co-operation within this multi-agent system of decentralised, unmanned gliders, investigating the threshold for communication range, which allows for optimal search whilst reducing both the cost of individual communication devices and the computational resources associated with the processing of data received by each aircraft. Reductions in communication radius are found to have a significant, negative impact upon the resulting efficiency of the system. To somewhat recover these losses, we utilise a sorting algorithm, determining information priority between any two aircraft in range. Furthermore, negotiation between aircraft is introduced, allowing aircraft to resolve any possible conflicts between selected paths, which helps to counteractany latency in the search heuristic

    Computational aspects of cellular intelligence and their role in artificial intelligence.

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    The work presented in this thesis is concerned with an exploration of the computational aspects of the primitive intelligence associated with single-celled organisms. The main aim is to explore this Cellular Intelligence and its role within Artificial Intelligence. The findings of an extensive literature search into the biological characteristics, properties and mechanisms associated with Cellular Intelligence, its underlying machinery - Cell Signalling Networks and the existing computational methods used to capture it are reported. The results of this search are then used to fashion the development of a versatile new connectionist representation, termed the Artificial Reaction Network (ARN). The ARN belongs to the branch of Artificial Life known as Artificial Chemistry and has properties in common with both Artificial Intelligence and Systems Biology techniques, including: Artificial Neural Networks, Artificial Biochemical Networks, Gene Regulatory Networks, Random Boolean Networks, Petri Nets, and S-Systems. The thesis outlines the following original work: The ARN is used to model the chemotaxis pathway of Escherichia coli and is shown to capture emergent characteristics associated with this organism and Cellular Intelligence more generally. The computational properties of the ARN and its applications in robotic control are explored by combining functional motifs found in biochemical network to create temporal changing waveforms which control the gaits of limbed robots. This system is then extended into a complete control system by combining pattern recognition with limb control in a single ARN. The results show that the ARN can offer increased flexibility over existing methods. Multiple distributed cell-like ARN based agents termed Cytobots are created. These are first used to simulate aggregating cells based on the slime mould Dictyostelium discoideum. The Cytobots are shown to capture emergent behaviour arising from multiple stigmergic interactions. Applications of Cytobots within swarm robotics are investigated by applying them to benchmark search problems and to the task of cleaning up a simulated oil spill. The results are compared to those of established optimization algorithms using similar cell inspired strategies, and to other robotic agent strategies. Consideration is given to the advantages and disadvantages of the technique and suggestions are made for future work in the area. The report concludes that the Artificial Reaction Network is a versatile and powerful technique which has application in both simulation of chemical systems, and in robotic control, where it can offer a higher degree of flexibility and computational efficiency than benchmark alternatives. Furthermore, it provides a tool which may possibly throw further light on the origins and limitations of the primitive intelligence associated with cells

    Advances in Evolutionary Algorithms

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    With the recent trends towards massive data sets and significant computational power, combined with evolutionary algorithmic advances evolutionary computation is becoming much more relevant to practice. Aim of the book is to present recent improvements, innovative ideas and concepts in a part of a huge EA field

    Abstract Book: Scales of Social, Environmental & Cultural Change in Past Societies

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    The interplay of environment, social relations, material culture, population dynamics, and human perception are the key factors of socio-environmental changes. The exploration of processes and parameters of societal change enable further exploration of transformations of human-environmental interactions. These processes and parameters are detectable in the development of, for example, settlement systems, material culture, or ritual sites, which link different socio-environmental components. Humans and environments deeply shaped each other, creating diverse social, environmental, and cultural constellations. On the one hand, examining the roots of social, environmental, and cultural phenomena and processes, which substantially marked past human development, can lead to a deeper understanding of the development of societies. On the other hand, a focus on transformation patterns within momentous developments of past societies opens up the possibility of identifying substantial and enduring re-organisation of socio-environmental interaction patterns
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