Periodicity Estimation Using Representations in Nested Periodic Dictionaries with Applications in Neural Engineering

In this dissertation, we investigate periodicity estimation with nested periodic dictionaries (NPDs), a newly introduced family of matrices that can capture periodicity in the data. We address two main problems. First, we study the detection of periodic signals using their representations in NPDs. To this end, the detection problem is posed as a composite hypothesis testing problem, where the signals are assumed to admit sparse representations in a Ramanujan Periodicity Transform (RPT) dictionary as an instance of NPDs. For the binary case, we develop a generalized likelihood ratio detector and obtain exact distributions of the test statistics in terms of confluent hypergeometric functions, along with flexible approximate distributions. Subsequently, we extend our approach to multi-hypothesis and multi-channel settings, where we account for spatial correlations between the different channels. We study the application of the proposed method in the detection of periodic brain responses to external visual stimuli, known as steady-state visually evoked potentials (SSVEPs), which is fundamental to the development of Brain Computer Interfaces. Results based on experiments with synthesized and real-data demonstrate that the RPT detector outperforms conventional spectral-based methods. Second, we address the problem of period estimation. Periodic signals composed of periodic mixtures admit sparse representations in NPDs. Therefore, their underlying hidden periods can be estimated by recovering the exact support of said representations. In this dissertation, we investigate support recovery guarantees of such signals in noise-free and noisy settings. While sufficient recovery conditions of sparse signals have been studied in the literature on compressive sensing, these conditions are of limited use for NPDs, because their analysis does not capture their intrinsic structures. Therefore, we establish new conditions based on a newly introduced notion of nested periodic coherence. Our results show significant improvement over generic recovery bounds as the conditions hold over a larger range of sparsity levels

Detection Of Visual Evoked Potentials Using Ramanujan Periodicity Transform For Real Time Brain Computer Interfaces

Repetitive visual stimuli induce periodic Visual Evoked Potentials (VEPs) in the brain that can be potentially identified in an EEG trace. The ability to distinguish frequencies and patterns due to different stimuli is the basis for brain computer interfaces (BCIs) used for communication and control of neurologically disabled patients. Since such responses are recorded in presence of high levels of noise from background brain processes, the detection task is rather challenging. In this work, we propose a detection approach for VEPs based on Ramanujan Periodicity Transform matrices (RPT), which have shown promise in detecting periodicities in data. Our results show that the RPT-based approach can outperform conventional spectral techniques and the state-of-the-art correlation analysis, and is more compatible with real-time BCIs which have to work with short duration EEG epochs. The proposed approach is fairly robust to unknown natural latencies in brain response

Collective analog bioelectronic computation

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student submitted PDF version of thesis.Includes bibliographical references (p. 677-710).In this thesis, I present two examples of fast-and-highly-parallel analog computation inspired by architectures in biology. The first example, an RF cochlea, maps the partial differential equations that describe fluid-membrane-hair-cell wave propagation in the biological cochlea to an equivalent inductor-capacitor-transistor integrated circuit. It allows ultra-broadband spectrum analysis of RF signals to be performed in a rapid low-power fashion, thus enabling applications for universal or software radio. The second example exploits detailed similarities between the equations that describe chemical-reaction dynamics and the equations that describe subthreshold current flow in transistors to create fast-and-highly-parallel integrated-circuit models of protein-protein and gene-protein networks inside a cell. Due to a natural mapping between the Poisson statistics of molecular flows in a chemical reaction and Poisson statistics of electronic current flow in a transistor, stochastic effects are automatically incorporated into the circuit architecture, allowing highly computationally intensive stochastic simulations of large-scale biochemical reaction networks to be performed rapidly. I show that the exponentially tapered transmission-line architecture of the mammalian cochlea performs constant-fractional-bandwidth spectrum analysis with O(N) expenditure of both analysis time and hardware, where N is the number of analyzed frequency bins. This is the best known performance of any spectrum-analysis architecture, including the constant-resolution Fast Fourier Transform (FFT), which scales as O(N logN), or a constant-fractional-bandwidth filterbank, which scales as O (N2).(cont.) The RF cochlea uses this bio-inspired architecture to perform real-time, on-chip spectrum analysis at radio frequencies. I demonstrate two cochlea chips, implemented in standard 0.13m CMOS technology, that decompose the RF spectrum from 600MHz to 8GHz into 50 log-spaced channels, consume < 300mW of power, and possess 70dB of dynamic range. The real-time spectrum analysis capabilities of my chips make them uniquely suitable for ultra-broadband universal or software radio receivers of the future. I show that the protein-protein and gene-protein chips that I have built are particularly suitable for simulation, parameter discovery and sensitivity analysis of interaction networks in cell biology, such as signaling, metabolic, and gene regulation pathways. Importantly, the chips carry out massively parallel computations, resulting in simulation times that are independent of model complexity, i.e., O(1). They also automatically model stochastic effects, which are of importance in many biological systems, but are numerically stiff and simulate slowly on digital computers. Currently, non-fundamental data-acquisition limitations show that my proof-of-concept chips simulate small-scale biochemical reaction networks at least 100 times faster than modern desktop machines. It should be possible to get 103 to 106 simulation speedups of genome-scale and organ-scale intracellular and extracellular biochemical reaction networks with improved versions of my chips. Such chips could be important both as analysis tools in systems biology and design tools in synthetic biology.by Soumyajit Mandal.Ph.D

Music and Digital Media: A planetary anthropology

Anthropology has neglected the study of music. Music and Digital Media shows how and why this should be redressed. It does so by enabling music to expand the horizons of digital anthropology, demonstrating how the field can build interdisciplinary links to music and sound studies, digital/media studies, and science and technology studies. Music and Digital Media is the first comparative ethnographic study of the impact of digital media on music worldwide. It offers a radical and lucid new theoretical framework for understanding digital media through music, showing that music is today where the promises and problems of the digital assume clamouring audibility. The book contains ten chapters, eight of which present comprehensive original ethnographies; they are bookended by an authoritative introduction and a comparative postlude. Five chapters address popular, folk, art and crossover musics in the global South and North, including Kenya, Argentina, India, Canada and the UK. Three chapters bring the digital experimentally to the fore, presenting pioneering ethnographies of an extra-legal peer-to-peer site and the streaming platform Spotify, a series of prominent internet-mediated music genres, and the first ethnography of a global software package, the interactive music platform Max. The book is unique in bringing ethnographic research on popular, folk, art and crossover musics from the global North and South into a comparative framework on a large scale, and creates an innovative new paradigm for comparative anthropology. It shows how music enlarges anthropology while demanding to be understood with reference to classic themes of anthropological theory

Music and Digital Media

Anthropology has neglected the study of music. Music and Digital Media shows how and why this should be redressed. It does so by enabling music to expand the horizons of digital anthropology, demonstrating how the field can build interdisciplinary links to music and sound studies, digital/media studies, and science and technology studies. Music and Digital Media is the first comparative ethnographic study of the impact of digital media on music worldwide. It offers a radical and lucid new theoretical framework for understanding digital media through music, showing that music is today where the promises and problems of the digital assume clamouring audibility. The book contains ten chapters, eight of which present comprehensive original ethnographies; they are bookended by an authoritative introduction and a comparative postlude. Five chapters address popular, folk, art and crossover musics in the global South and North, including Kenya, Argentina, India, Canada and the UK. Three chapters bring the digital experimentally to the fore, presenting pioneering ethnographies of anextra-legal peer-to-peer site and the streaming platform Spotify, a series of prominent internet-mediated music genres, and the first ethnography of a global software package, the interactive music platform Max. The book is unique in bringing ethnographic research on popular, folk, art and crossover musics from the global North and South into a comparative framework on a large scale, and creates an innovative new paradigm for comparative anthropology. It shows how music enlarges anthropology while demanding to be understood with reference to classic themes of anthropological theory. Praise for Music and Digital Media ‘Music and Digital Media is a groundbreaking update to our understandings of sound, media, digitization, and music. Truly transdisciplinary and transnational in scope, it innovates methodologically through new models for collaboration, multi-sited ethnography, and comparative work. It also offers an important defense of—and advancement of—theories of mediation.’ Jonathan Sterne, Communication Studies and Art History, McGill University 'Music and Digital Media is a nuanced exploration of the burgeoning digital music scene across both the global North and the global South. Ethnographically rich and theoretically sophisticated, this collection will become the new standard for this field.' Anna Tsing, Anthropology, University of California at Santa Cruz 'The global drama of music's digitisation elicits extreme responses – from catastrophe to piratical opportunism – but between them lie more nuanced perspectives. This timely, absolutely necessary collection applies anthropological understanding to a deliriously immersive field, bringing welcome clarity to complex processes whose impact is felt far beyond what we call music.' David Toop, London College of Communication, musician and writer ‘Spanning continents and academic disciplines, the rich ethnographies contained in Music and Digital Media makes it obligatory reading for anyone wishing to understand the complex, contradictory, and momentous effects that digitization is having on musical cultures.’ Eric Drott, Music, University of Texas, Austin ‘This superb collection, with an authoritative overview as its introduction, represents the state of the art in studies of the digitalisation of music. It is also a testament to what anthropology at its reflexive best can offer the rest of the social sciences and humanities.’ David Hesmondhalgh, Media and Communication, University of Leeds ‘This exciting volume forges new ground in the study of local conditions, institutions, and sounds of digital music in the Global South and North. The book’s planetary scope and its commitment to the “messiness” of ethnographic sites and concepts amplifies emergent configurations and meanings of music, the digital, and the aesthetic.’ Marina Peterson, Anthropology, University of Texas, Austi

Music and Digital Media

Anthropology has neglected the study of music. Music and Digital Media shows how and why this should be redressed. It does so by enabling music to expand the horizons of digital anthropology, demonstrating how the field can build interdisciplinary links to music and sound studies, digital/media studies, and science and technology studies. Music and Digital Media is the first comparative ethnographic study of the impact of digital media on music worldwide. It offers a radical and lucid new theoretical framework for understanding digital media through music, showing that music is today where the promises and problems of the digital assume clamouring audibility. The book contains ten chapters, eight of which present comprehensive original ethnographies; they are bookended by an authoritative introduction and a comparative postlude. Five chapters address popular, folk, art and crossover musics in the global South and North, including Kenya, Argentina, India, Canada and the UK. Three chapters bring the digital experimentally to the fore, presenting pioneering ethnographies of anextra-legal peer-to-peer site and the streaming platform Spotify, a series of prominent internet-mediated music genres, and the first ethnography of a global software package, the interactive music platform Max. The book is unique in bringing ethnographic research on popular, folk, art and crossover musics from the global North and South into a comparative framework on a large scale, and creates an innovative new paradigm for comparative anthropology. It shows how music enlarges anthropology while demanding to be understood with reference to classic themes of anthropological theory. Praise for Music and Digital Media ‘Music and Digital Media is a groundbreaking update to our understandings of sound, media, digitization, and music. Truly transdisciplinary and transnational in scope, it innovates methodologically through new models for collaboration, multi-sited ethnography, and comparative work. It also offers an important defense of—and advancement of—theories of mediation.’ Jonathan Sterne, Communication Studies and Art History, McGill University 'Music and Digital Media is a nuanced exploration of the burgeoning digital music scene across both the global North and the global South. Ethnographically rich and theoretically sophisticated, this collection will become the new standard for this field.' Anna Tsing, Anthropology, University of California at Santa Cruz 'The global drama of music's digitisation elicits extreme responses – from catastrophe to piratical opportunism – but between them lie more nuanced perspectives. This timely, absolutely necessary collection applies anthropological understanding to a deliriously immersive field, bringing welcome clarity to complex processes whose impact is felt far beyond what we call music.' David Toop, London College of Communication, musician and writer ‘Spanning continents and academic disciplines, the rich ethnographies contained in Music and Digital Media makes it obligatory reading for anyone wishing to understand the complex, contradictory, and momentous effects that digitization is having on musical cultures.’ Eric Drott, Music, University of Texas, Austin ‘This superb collection, with an authoritative overview as its introduction, represents the state of the art in studies of the digitalisation of music. It is also a testament to what anthropology at its reflexive best can offer the rest of the social sciences and humanities.’ David Hesmondhalgh, Media and Communication, University of Leeds ‘This exciting volume forges new ground in the study of local conditions, institutions, and sounds of digital music in the Global South and North. The book’s planetary scope and its commitment to the “messiness” of ethnographic sites and concepts amplifies emergent configurations and meanings of music, the digital, and the aesthetic.’ Marina Peterson, Anthropology, University of Texas, Austi

Back to the future. The future in the past: ICDHS 10th+1 Barcelona 2018: Conference proceedings book

Obra dedicada a la memòria d'Anna Calvera (1954–2018).Conté: 0. Opening pages -- 1.1 Territories in the scene of globalised design: localisms and cosmopolitanisms -- 1.2 Designing the histories of southern designs -- 1.3 Mediterranean-ness: an inquiry into design and design history -- 1.4 From ideology to methodology: design histories and current developments in post-socialist countries -- 1.5 [100th anniversary of the Bauhaus Foundation]: tracing the map of the diaspora of its students -- 1.6 Design history: gatekeeper of the past and passport to a meaningful future? -- 1.7 Constructivism and deconstructivism: global development and criticism -- 1.8 An expanded global framework for design history -- 1.9 Design museums network: strengthening design by making it part of cultural legacy -- 1.10 Types and histories: past and present issues of type and book design -- 2.1 Design aesthetics: beyond the pragmatic experience and phenomenology -- 2.2 Public policies on design and design-driven innovation -- 2.3 Digital humanities: how does design in today's digital realm respond to what we need? -- 2.4 Design studies: design methods and methodology, the cognitive approach -- 2.5 Vehicles of design criticism -- 3 Open session: research and works in progress (1) -- 3 Open session: research and works in progress (2) -- Addenda: 10th+I keywords mapInternational Committee of Design History and Design Studies. Conference (11a : 2018 : Barcelona, Catalunya),ICDHS is the acronym of the International Committee of De­sign History and Design Studies, an organisation that brings together scholars from Spain, Cuba, Turkey, Mexico, Finland, Japan, Belgium, the Netherlands, Brazil, Portugal, the US, Tai­wan, Canada and the UK. Since 1999, when the Design and Art History departments of the University of Barcelona organised the first edition of the ICDHS, a conference has been held every two years at a different venue around the world. These conferences have had two dis­tinct aims: first, to present original research in the fields of Design History and Design Studies and, second, to include contributions in these fields from non-hegemonic countries, offering a speaking platform to many scientific communities that are already active or are forming and developing. For that reason, the structure of the conferences combines many paral­lel strands, including poster presentations and keynote speak­ers who lecture on the conferences’ main themes. The 2018 event is rather special. The Taipei 2016 conference was the 10th edition and a commemoration of the ten celebrations to date. Returning to Barcelona in 2018 marks the end of one stage and the beginning of a new one for the Committee. The numbering chosen—“10+1”—also means that Barcelona 2018 is both an end and a beginning in the ICDHS’s own history. The book brings together 137 papers delivered at the ICDHS 10th+1 Conference held in Barcelona on 29–31 October 2018. The papers are preceded by texts of the four keynote lectures and a written tribute from the ICDHS Board to its founder and figurehead, Anna Calvera (1954–2018). The Conference, and the book, are dedicated to her memory