314 research outputs found
Proceedings of the Second International Mobile Satellite Conference (IMSC 1990)
Presented here are the proceedings of the Second International Mobile Satellite Conference (IMSC), held June 17-20, 1990 in Ottawa, Canada. Topics covered include future mobile satellite communications concepts, aeronautical applications, modulation and coding, propagation and experimental systems, mobile terminal equipment, network architecture and control, regulatory and policy considerations, vehicle antennas, and speech compression
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Open-Source, Open-Architecture SoftwarePlatform for Plug-InElectric Vehicle SmartCharging in California
This interdisciplinary eXtensible Building Operating System–Vehicles project focuses on controlling plug-in electric vehicle charging at residential and small commercial settings using a novel and flexible open-source, open-architecture charge communication and control platform. The platform provides smart charging functionalities and benefits to the utility, homes, and businesses.This project investigates four important areas of vehicle-grid integration research, integrating technical as well as social and behavioral dimensions: smart charging user needs assessment, advanced load control platform development and testing, smart charging impacts, benefits to the power grid, and smart charging ratepayer benefits
Design requirements for SRB production control system. Volume 5: Appendices
A questionnaire to be used to screen potential candidate production control software packages is presented
Confidential Consortium Framework: Secure Multiparty Applications with Confidentiality, Integrity, and High Availability
Confidentiality, integrity protection, and high availability, abbreviated to
CIA, are essential properties for trustworthy data systems. The rise of cloud
computing and the growing demand for multiparty applications however means that
building modern CIA systems is more challenging than ever. In response, we
present the Confidential Consortium Framework (CCF), a general-purpose
foundation for developing secure stateful CIA applications. CCF combines
centralized compute with decentralized trust, supporting deployment on
untrusted cloud infrastructure and transparent governance by mutually untrusted
parties. CCF leverages hardware-based trusted execution environments for
remotely verifiable confidentiality and code integrity. This is coupled with
state machine replication backed by an auditable immutable ledger for data
integrity and high availability. CCF enables each service to bring its own
application logic, custom multiparty governance model, and deployment scenario,
decoupling the operators of nodes from the consortium that governs them. CCF is
open-source and available now at https://github.com/microsoft/CCF.Comment: 16 pages, 9 figures. To appear in the Proceedings of the VLDB
Endowment, Volume 1
USCID 14th technical conference
Presented at Contemporary challenges for irrigation and drainage: proceedings from the USCID 14th technical conference on irrigation, drainage and flood control held on June 3-6, 1998 in Phoenix, Arizona.Metering of farm water deliveries in the Imperial Irrigation District has always been a costly and difficult procedure. Due to existing structural and environmental conditions, many of the traditional methods of metering deliveries had in the past proved cumbersome or unsuccessful. With funding provided by the IID/MWD Water Conservation Program, a method for utilizing ultrasonic transducers for metering farm water deliveries under orifice flow conditions has been developed. These on-farm water level sensors were designed to be portable, environmentally rugged, solar powered, simple to operate and maintain, and visually unobtrusive to minimize vandalism. This paper describes the construction of the on-farm water level sensors and their function as a useful tool in providing rapid and accurate irrigation evaluations to farmers
NASA Tech Briefs, June 2000
Topics include: Computer-Aided Design and Engineering; Electronic Components and Circuits; Electronic Systems; Test and Measurement; Physical Sciences; Materials; Computer Programs; Computers and Peripherals
Weaving time into system architecture : new perspectives on flexibility, spacecraft design lifetime, and on-orbit servicing
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, June, 2002.Includes bibliographical references (leaves 203-214).A roadmap for a comprehensive treatment of issues of flexibility in system design is developed that addresses the following questions: 1) What are the characteristic features of flexibility in system design? Can one clearly and unambiguously characterize flexibility, and disentangle it from closely related concepts? 2) What drives the need for flexibility in system design, and what are the attributes of an environment in which flexible designs should be sought and fielded? 3) How can one embed flexibility in a system design? 4) What are the trade-offs associated with designing for flexibility? What is the value of flexibility and what are the associated penalties (cost, performance, risk, etc.), if any? These are the fundamental questions around which this thesis revolves. The first part of this work addresses the first two questions: Flexibility of a design is here defined as the property of a system that allows it to respond to changes in its initial objectives and requirements-both in terms of capabilities and attributes-occurring after the system has been fielded, i.e., is in operation, in a timely and cost-effective way. It is argued that flexibility should be sought when: 1) the uncertainty in a system's environment is such that there is a need to mitigate market risks, in the case of a commercial venture, and reduce a design's exposure to uncertainty in its environment, 2) the system's technology base evolves on a time scale considerably shorter than the system's design lifetime, thus requiring a solution for mitigating risks associated with technology obsolescence.(cont.) In other words, flexibility reduces a design's exposure to uncertainty, and provides a solution for mitigating market risks as well as risks associated with technology obsolescence. One way flexibility manifests its criticality to systems architects is in the specification of the system design lifetime requirement. The second part of this work addresses issues of design lifetime, and ways to provide and value flexibility in the particular case of space systems. First, it is shown that design lifetime is a key requirement in sizing various spacecraft subsystems. Second, spacecraft cost profiles as a function of the design lifetime are established and a cost per operational day metric is introduced. It is found that a cost penalty of 30% to 40% is incurred when designing a spacecraft for fifteen years instead of three years, all else being equal. Also, the cost per operational day decreases monotonically as a function of the spacecraft design lifetime. An augmented perspective on system architecture is proposed (diachronic) that complements traditional views on system architecture (synchronic). It is suggested for example that the system's design lifetime is a fundamental component of system architecture although one cannot see it or touch it. Consequently, cost, utility, and value per unit time metrics are introduced and explored in order to identify optimal design lifetimes for complex systems in general, and space systems in particular. Results show that an optimal design lifetime for space systems exists, even in the case of constant expected revenues per day over the system's lifetime ...by Joseph Homer Saleh.Ph.D
An instruction systolic array architecture for multiple neural network types
Modern electronic systems, especially sensor and imaging systems, are beginning to
incorporate their own neural network subsystems. In order for these neural systems to learn in
real-time they must be implemented using VLSI technology, with as much of the learning
processes incorporated on-chip as is possible. The majority of current VLSI implementations
literally implement a series of neural processing cells, which can be connected together in an
arbitrary fashion. Many do not perform the entire neural learning process on-chip, instead
relying on other external systems to carry out part of the computation requirements of the
algorithm.
The work presented here utilises two dimensional instruction systolic arrays in an attempt to
define a general neural architecture which is closer to the biological basis of neural networks - it
is the synapses themselves, rather than the neurons, that have dedicated processing units. A
unified architecture is described which can be programmed at the microcode level in order to
facilitate the processing of multiple neural network types.
An essential part of neural network processing is the neuron activation function, which can
range from a sequential algorithm to a discrete mathematical expression. The architecture
presented can easily carry out the sequential functions, and introduces a fast method of
mathematical approximation for the more complex functions. This can be evaluated on-chip,
thus implementing the entire neural process within a single system.
VHDL circuit descriptions for the chip have been generated, and the systolic processing
algorithms and associated microcode instruction set for three different neural paradigms have
been designed. A software simulator of the architecture has been written, giving results for
several common applications in the field
Telecommunication Systems
This book is based on both industrial and academic research efforts in which a number of recent advancements and rare insights into telecommunication systems are well presented. The volume is organized into four parts: "Telecommunication Protocol, Optimization, and Security Frameworks", "Next-Generation Optical Access Technologies", "Convergence of Wireless-Optical Networks" and "Advanced Relay and Antenna Systems for Smart Networks." Chapters within these parts are self-contained and cross-referenced to facilitate further study
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