The 1991 3rd NASA Symposium on VLSI Design

Papers from the symposium are presented from the following sessions: (1) featured presentations 1; (2) very large scale integration (VLSI) circuit design; (3) VLSI architecture 1; (4) featured presentations 2; (5) neural networks; (6) VLSI architectures 2; (7) featured presentations 3; (8) verification 1; (9) analog design; (10) verification 2; (11) design innovations 1; (12) asynchronous design; and (13) design innovations 2

New Directions for Contact Integrators

Contact integrators are a family of geometric numerical schemes which guarantee the conservation of the contact structure. In this work we review the construction of both the variational and Hamiltonian versions of these methods. We illustrate some of the advantages of geometric integration in the dissipative setting by focusing on models inspired by recent studies in celestial mechanics and cosmology.Comment: To appear as Chapter 24 in GSI 2021, Springer LNCS 1282

Applications to Earth physics: Very-long-baseline interferometry and data analysis

A range of very long baseline interferometry experiments applied to Earth physics are covered

Deep Learning Techniques for Music Generation -- A Survey

This paper is a survey and an analysis of different ways of using deep learning (deep artificial neural networks) to generate musical content. We propose a methodology based on five dimensions for our analysis: Objective - What musical content is to be generated? Examples are: melody, polyphony, accompaniment or counterpoint. - For what destination and for what use? To be performed by a human(s) (in the case of a musical score), or by a machine (in the case of an audio file). Representation - What are the concepts to be manipulated? Examples are: waveform, spectrogram, note, chord, meter and beat. - What format is to be used? Examples are: MIDI, piano roll or text. - How will the representation be encoded? Examples are: scalar, one-hot or many-hot. Architecture - What type(s) of deep neural network is (are) to be used? Examples are: feedforward network, recurrent network, autoencoder or generative adversarial networks. Challenge - What are the limitations and open challenges? Examples are: variability, interactivity and creativity. Strategy - How do we model and control the process of generation? Examples are: single-step feedforward, iterative feedforward, sampling or input manipulation. For each dimension, we conduct a comparative analysis of various models and techniques and we propose some tentative multidimensional typology. This typology is bottom-up, based on the analysis of many existing deep-learning based systems for music generation selected from the relevant literature. These systems are described and are used to exemplify the various choices of objective, representation, architecture, challenge and strategy. The last section includes some discussion and some prospects.Comment: 209 pages. This paper is a simplified version of the book: J.-P. Briot, G. Hadjeres and F.-D. Pachet, Deep Learning Techniques for Music Generation, Computational Synthesis and Creative Systems, Springer, 201

A Scalable Flash-Based Hardware Architecture for the Hierarchical Temporal Memory Spatial Pooler

Hierarchical temporal memory (HTM) is a biomimetic machine learning algorithm focused upon modeling the structural and algorithmic properties of the neocortex. It is comprised of two components, realizing pattern recognition of spatial and temporal data, respectively. HTM research has gained momentum in recent years, leading to both hardware and software exploration of its algorithmic formulation. Previous work on HTM has centered on addressing performance concerns; however, the memory-bound operation of HTM presents significant challenges to scalability. In this work, a scalable flash-based storage processor unit, Flash-HTM (FHTM), is presented along with a detailed analysis of its potential scalability. FHTM leverages SSD flash technology to implement the HTM cortical learning algorithm spatial pooler. The ability for FHTM to scale with increasing model complexity is addressed with respect to design footprint, memory organization, and power efficiency. Additionally, a mathematical model of the hardware is evaluated against the MNIST dataset, yielding 91.98% classification accuracy. A fully custom layout is developed to validate the design in a TSMC 180nm process. The area and power footprints of the spatial pooler are 30.538mm2 and 5.171mW, respectively. Storage processor units have the potential to be viable platforms to support implementations of HTM at scale

Advanced Battery Technologies: New Applications and Management Systems

In recent years, lithium-ion batteries (LIBs) have been increasingly contributing to the development of novel engineering systems with energy storage requirements. LIBs are playing an essential role in our society, as they are being used in a wide variety of applications, ranging from consumer electronics, electric mobility, renewable energy storage, biomedical applications, or aerospace systems. Despite the remarkable achievements and applicability of LIBs, there are several features within this technology that require further research and improvements. In this book, a collection of 10 original research papers addresses some of those key features, including: battery testing methodologies, state of charge and state of health monitoring, and system-level power electronics applications. One key aspect to emphasize when it comes to this book is the multidisciplinary nature of the selected papers. The presented research was developed at university departments, institutes and organizations of different disciplines, including Electrical Engineering, Control Engineering, Computer Science or Material Science, to name a few examples. The overall result is a book that represents a coherent collection of multidisciplinary works within the prominent field of LIBs

A propagation effects handbook for satellite systems design. A summary of propagation impairments on 10-100 GHz satellite links, with techniques for system design

This handbook provides satellite system engineers with a concise summary of the major propagation effects experienced on Earth-space paths in the 10 to 100 GHz frequency range. The dominant effect, attenuation due to rain, is dealt with in terms of both experimental data from measurements made in the U.S. and Canada, and the mathematical and conceptual models devised to explain the data. Rain systems, rain and attenuation models, depolarization and experimental data are described. The design techniques recommended for predicting propagation effects in Earth-space communications systems are presented. The questions of where in the system design process the effects of propagation should be considered, and what precautions should be taken when applying the propagation results are addressed in order to bridge the gap between the propagation research data and the classical link budget analysis of Earth-space communications system

Precipitation Measurements From Space: Workshop report. An element of the climate observing system study

Global climate, agricultural uses for precipitation information, hydrological uses for precipitation, severe thunderstorms and local weather, global weather are addressed. Ground truth measurement, visible and infrared techniques, microwave radiometry and hybrid precipitation measurements, and spaceborne radar are discussed

Quantum brane cosmology

This thesis deals with the interaction of quantum mechanical models and cosmologies based on brane universes, an area of active theoretical speculation over the last five years.For convenience, the material has been split into two parts. Part 1 deals with a selection of background topics which are necessary and relevant to the original research. This research is presented in Part 2. In addition, some auxiliary topics, both more elementary and more advanced, are described in the appendices. The selection of background topics has been influenced by the various techniques, physical theories and mathematical technologies which play a major role in the work presented in Part 2. Although the exposition is ad hoc, an attempt has been made to systematically develop portions where the technique (or use of it) may be unfamiliar.A fairly complete treatment of the necessary mathematical scaffolding is supplied. Although important, this material is familiar or strongly mathematical, and is deferred to the appendices. This includes an elementary survey of functional analysis in Appendix A, sufficient to support a discussion of the path integral. The path integral formalism is used extensively throughout this thesis, and, where available, constitutes our preferred representation of quantum mechanics. The discussion is limited to the relevant portions of the theory: functions in Banacli spaces, and the Sturm-Liouville basis (technology which appears many times in Part 2); direct evaluation of Gaussian functional integrals, ubiquitous in field theory calculations; and ((-function regularization of the operator determinants to which such Gaussian integrals give rise, which has a direct application in Chapter 9. In Appendix B we describe the necessary framework of differential geometry which supports general relativity, and low-energy discussions of string theory. All calculations in metric gravity are based on differential geometry, together with a good proportion of the technology which buttresses quantum field theory on curved space time, string theory, and some more advanced representations of quantum mechanics (see below). All of this is used extensively throughout both parts of the thesis. We include some more advanced topological technology which supports the discussion of string compactification. General results from compactification theory, when appropriately interpreted in the brane context, contribute important stability results for zero-modes of the Kaluza—Klein fields, and provide a natural home for the spectral KK technology used (in one form or another) throughout Part 2, but most especially in Chapter 7 and Chapter 8. Einstein gravity and Yang-Mills theory are set in context as examples of connexions on fibre bundles