1,721 research outputs found

    Object-oriented Tools for Distributed Computing

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    Distributed computing systems are proliferating, owing to the availability of powerful, affordable microcomputers and inexpensive communication networks. A critical problem in developing such systems is getting application programs to interact with one another across a computer network. Remote interprogram connectivity is particularly challenging across heterogeneous environments, where applications run on different kinds of computers and operating systems. NetWorks! (trademark) is an innovative software product that provides an object-oriented messaging solution to these problems. This paper describes the design and functionality of NetWorks! and illustrates how it is being used to build complex distributed applications for NASA and in the commercial sector

    The Covering-Assignment Problem for Swarm-powered Ad-hoc Clouds: A Distributed 3D Mapping Use-case

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    The popularity of drones is rapidly increasing across the different sectors of the economy. Aerial capabilities and relatively low costs make drones the perfect solution to improve the efficiency of those operations that are typically carried out by humans (e.g., building inspection, photo collection). The potential of drone applications can be pushed even further when they are operated in fleets and in a fully autonomous manner, acting de facto as a drone swarm. Besides automating field operations, a drone swarm can serve as an ad-hoc cloud infrastructure built on top of computing and storage resources available across the swarm members and other connected elements. Even in the absence of Internet connectivity, this cloud can serve the workloads generated by the swarm members themselves, as well as by the field agents operating within the area of interest. By considering the practical example of a swarm-powered 3D reconstruction application, we present a new optimization problem for the efficient generation and execution, on top of swarm-powered ad-hoc cloud infrastructure, of multi-node computing workloads subject to data geolocation and clustering constraints. The objective is the minimization of the overall computing times, including both networking delays caused by the inter-drone data transmission and computation delays. We prove that the problem is NP-hard and present two combinatorial formulations to model it. Computational results on the solution of the formulations show that one of them can be used to solve, within the configured time-limit, more than 50% of the considered real-world instances involving up to two hundred images and six drones

    Microcomputer security

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    https://egrove.olemiss.edu/aicpa_guides/1484/thumbnail.jp

    Marshall Avionics Testbed System (MAST)

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    Work accomplished in the summer of 1989 in association with the NASA/ASEE Summer Faculty Research Fellowship Program at Marshall Space Flight Center is summarized. The project was aimed at developing detailed specifications for the Marshall Avionics System Testbed (MAST). This activity was to include the definition of the testbed requirements and the development of specifications for a set of standard network nodes for connecting the testbed to a variety of networks. The project was also to include developing a timetable for the design, implementation, programming and testing of the testbed. Specifications of both hardware and software components for the system were to be included

    Auditing in common computer environments; Auditing procedure study;

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    https://egrove.olemiss.edu/aicpa_guides/1039/thumbnail.jp

    USING EMBEDDED TECHNOLOGY IN END-USER PROGRAMMING OF SMART SPACES WITH MOBILE DEVICES

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    A recent shift in computing paradigm from stand-alone microcomputers and mainframes towards entirely pervasivecomputing where billions of miniature, ubiquitous inter-connected computing elements weave themselves into thefabric of everyday life. Embedded systems run the computing devices hidden inside every object and appliance suchas cell phones, toys, handheld PDAs, cameras, microwave ovens, cars, airplanes, etc. These numerous, easilyaccessible devices connected to each other and to network infrastructure exhibit context-awareness of anenvironment in order to optimize their operation in that environment. In this paper, we examined embedded systemsin end-user programming of smart spaces with mobile devices. We designed and implemented a microcontrollerbasedsystem capable of monitoring and controlling the electronic appliances in a home from any location. Weadopted a task-driven computing approach of the composition of the semantic web. The end user uses thefunctionality of the networked devices in the home as semantic web services to arbitrarily form his request whichinvolves the typing of SMS through the user-friendly interface of a Java enabled mobile phone. An Arduinomicrocontroller for generating the timing and control signals programmed using Wiring language was used. TheGSM wireless technology was used for transmission and reception of the data. Our work addresses the problem ofenergy wastage and domestic accidents by enabling end-users to easily use their mobile devices to monitor andinstruct their home devices from any location over a wireless network.Keywords: Embedded Technology, Smart Spaces, End-User Programming, Mobile Devices, Pervasive Networkin

    A wireless, real-time, social music performance system for mobile phones

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    The paper reports on the Cellmusic system: a real-time, wireless distributed composition and performance system designed for domestic mobile devices. During a performance, each mobile device communicates with others, and may create sonic events in a passive (non interactive) mode or may influence the output of other devices. Cellmusic distinguishes itself from other mobile phone performance environments in that it is intended for performance in ad hoc locations, with services and performances automatically and dynamically adapting to the number of devices within a given proximity. It is designed to run on a number of mobile phone platforms to allow as wider distribution as possible, again distinguishing itself from other mobile performance systems which primarily run on a single device. Rather than performances being orchestrated or managed, it is intended that users will access it and create a performance in the same manner that they use mobile phones for interacting socially at different times throughout the day. However, this does not preclude the system being used in a more traditional performance environment. This accessibility and portability make it an ideal platform for sonic artists who choose to explore a variety of physical environments (such as parks and other public spaces)

    Deep Space Network information system architecture study

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    The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control

    ACUTA eNews July 1987, Vol. 16, No. 1987

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    In This Issue Stanford University switches to the Meridian SL-100 The Broadband Cable Network Party Line Microcomputers Found More Available -and More Often Required -at Selective College
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