5 research outputs found

    Recent Advances in Text Analysis

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    Text analysis is an interesting research area in data science and has various applications, such as in artificial intelligence, biomedical research, and engineering. We review popular methods for text analysis, ranging from topic modeling to the recent neural language models. In particular, we review Topic-SCORE, a statistical approach to topic modeling, and discuss how to use it to analyze MADStat - a dataset on statistical publications that we collected and cleaned. The application of Topic-SCORE and other methods on MADStat leads to interesting findings. For example, 1111 representative topics in statistics are identified. For each journal, the evolution of topic weights over time can be visualized, and these results are used to analyze the trends in statistical research. In particular, we propose a new statistical model for ranking the citation impacts of 1111 topics, and we also build a cross-topic citation graph to illustrate how research results on different topics spread to one another. The results on MADStat provide a data-driven picture of the statistical research in 19751975--20152015, from a text analysis perspective

    Adaptive networks for robotics and the emergence of reward anticipatory circuits

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    Currently the central challenge facing evolutionary robotics is to determine how best to extend the range and complexity of behaviour supported by evolved neural systems. Implicit in the work described in this thesis is the idea that this might best be achieved through devising neural circuits (tractable to evolutionary exploration) that exhibit complementary functional characteristics. We concentrate on two problem domains; locomotion and sequence learning. For locomotion we compare the use of GasNets and other adaptive networks. For sequence learning we introduce a novel connectionist model inspired by the role of dopamine in the basal ganglia (commonly interpreted as a form of reinforcement learning). This connectionist approach relies upon a new neuron model inspired by notions of energy efficient signalling. Two reward adaptive circuit variants were investigated. These were applied respectively to two learning problems; where action sequences are required to take place in a strict order, and secondly, where action sequences are robust to intermediate arbitrary states. We conclude the thesis by proposing a formal model of functional integration, encompassing locomotion and sequence learning, extending ideas proposed by W. Ross Ashby. A general model of the adaptive replicator is presented, incoporating subsystems that are tuned to continuous variation and discrete or conditional events. Comparisons are made with Ross W. Ashby's model of ultrastability and his ideas on adaptive behaviour. This model is intended to support our assertion that, GasNets (and similar networks) and reward adaptive circuits of the type presented here, are intrinsically complementary. In conclusion we present some ideas on how the co-evolution of GasNet and reward adaptive circuits might lead us to significant improvements in the synthesis of agents capable of exhibiting complex adaptive behaviour

    Dual reality : an emerging medium

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2007.Includes bibliographical references (p. 143-151).The commoditization of low-power radios, a rich set of sensors, longer-lasting batteries, and feature-rich microcontrollers has prompted significant research efforts to imbue physical environments with the responsiveness and awareness afforded by ubiquitous, unobtrusive, low-maintenance sensor networks. However, despite these technical advances, there has been relatively little progress toward finding compelling applications enabled by such sensor networks. What few applications have been demonstrated generally use sensor networks to passively monitor environments either inaccessible or uninteresting to people, such as remote wilderness, factory floors, and health care scenarios. Yet, by definition, any "killer application" of sensor networks must be both popular and widespread. At the same time, online virtual worlds promising complete freedom of creation and interaction are quickly becoming economically, socially, and technically feasible and are making inroads into the mass media market. Yet, despite their popularity, or maybe even because of it, today's online virtual worlds are marred by a stagnation and emptiness inherent in environments so disconnected from the physical world. Furthermore, the demand for richer modes of self-expression in virtual worlds remains unmet. This dissertation proposes the convergence of sensor networks and virtual worlds not only as a possible solution to their respective limitations, but also as the beginning of a new creative medium. In the "dual reality" resulting from this convergence, both the real and virtual worlds are complete unto themselves, but also enhanced by the ability to mutually reflect, influence, and merge into each other by means of sensor/actuator networks deeply embedded in everyday environments.As a medium, dual reality has the potential to elevate mass creation of media to the same heights television elevated the mass consumption of media and the Internet elevated the mass communication of media. This dissertation describes a full implementation of a dual reality system using a popular online virtual world and a human-centric sensor network designed around a common electrical power strip. Example applications, interaction techniques, and design strategies for the dual reality domain are demonstrated and discussed.by Joshua Harlan Lifton.Ph.D

    Striking a balance between the secrecy of online communication and online criminal investigation in South Africa

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    In the Republic of South Africa (‘RSA’), there are exponentially increasing and indeterminable consequential risks and breaches involved in the spontaneous and indispensable personal, official and general anatomic uses of the quicksilver, complex and delicate conscriptive, interoperable, non-compartmentalised and non-passworded compartmentalised online communication devices, technologies, networks, applications, and services. These risks and breaches result in a disequilibrium in the following antithetical legal vector argument. On the one hand, these risks and breaches are attributed to the non-recognition, and inadequate protection of the independent and unique right in online communication, the concept of which originates from the jurisprudence of the broad gamut of the right to privacy. On the other hand, these risks are exacerbated by the increasing, unrestrictive and perpetual techno-legal abuse of online communication by law enforcement agencies or officers (‘LEAs’ or ‘LEOs’) of the alternative conduct of the covert online criminal investigation (‘OCI’) of serious offences, arising from the dearth of and non-compliance with the regulation for the conduct of an OCI. This dual study clinically examines the irreconcilable conflict between the protection of the right in online communication and the public criminal mandate of the State to conduct an OCI of serious offences. Firstly, this study investigates the existence of the levels of risks involved in the conscriptive, interoperable, non-compartmentalised and non-passworded compartmentalised continua of privacy interests in online communication, requiring a corresponding protective and secure regime in the conduct of an OCI. Secondly, it probes into the various substantive and procedural thresholds required in the limitation of the right in online communication when conducting an OCI. Lastly, it examines the mechanisms for institutional and structural independence, competence, due process, separation of powers and checks and balances in the conduct and oversight of the conduct of an OCI in the RSA. Consequently, the examination of the above issues reveals the absence, inadequacy of, and non-compliance with the substantive and procedural constitutional, legislative and policy framework that caters for the protection of the right in online communication and the conduct of an OCI in the RSA. Accordingly and specifically, this study proposes that the RSA adopts an adequate constitutional and single legislative framework to address the contemporary societal techno-legal tapestry in the conflict between the right in online communication and the conduct of an OCI of serious offences in the RSA as follows. Firstly, it is imperative to unequivocally, in the legal framework in the RSA, including the Constitution, consider the existence of higher levels of risks and the simultaneous or consequential recognition of the higher levels of protection of the invaluability in online communication —including the emerging quantum computing— in contrast with non-online communications. This contrast hierarchically compels the unimpeachable protection of the independent right to the secrecy of online communication (‘SOC’), which is inadequately and incongruously protected as mere online privacy in section 14 of the Constitution of the RSA. Secondly, it is equally crucial to consider the application of or compliance with adequate substantive and procedural scientific threshold requirements to conduct an OCI of serious offences in the RSA. These requirements include the application of: online conscription; section 205 of the Criminal Procedure Act; ‘no server, but law’ principle as opposed to the U.S. ‘no server, no law’ principle; robotic and non-robotic OCI; ex-parte and non-ex-parte verbal and written quadripartite techno-legal individual and mass online criminal investigation of privileged and non-privileged online communications by ghost and non-ghost applicants; pre and post OCI data management procedure and admissibility of void and voidable evidence. Furthermore, it is of great importance to apply the all-embracing proportionality principle in section 36 of the Constitution in which this study, from a contrarian belief, classifies serious offences into six categories under four criteria and propounds some definite and functional Popoola mathematical and non-mathematical formulae in the standard of proof required to conduct an OCI, the procedure of which should be incorporated in a legislation. Thirdly and finally, it is of utmost significance to, in the legal framework in the RSA, including the Constitution, consider the application of or compliance with safeguard mechanisms in the conduct of an OCI. These mechanisms are to ensure the inviolability of the principles or requirements of structural and institutional independence, competence, due process, separation of powers and checks and balances in the conduct and oversight of the conduct of an OCI of serious offences by LEAs or LEOs and other stakeholders respectively.Public, Constitutional, and International LawLL. D
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