45,056 research outputs found
CSP channels for CAN-bus connected embedded control systems
Closed loop control system typically contains multitude of sensors and actuators operated simultaneously. So they are parallel and distributed in its essence. But when mapping this parallelism to software, lot of obstacles concerning multithreading communication and synchronization issues arise. To overcome this problem, the CT kernel/library based on CSP algebra has been developed. This project (TES.5410) is about developing communication extension to the CT library to make it applicable in distributed systems. Since the library is tailored for control systems, properties and requirements of control systems are taken into special consideration. Applicability of existing middleware solutions is examined. A comparison of applicable fieldbus protocols is done in order to determine most suitable ones and CAN fieldbus is chosen to be first fieldbus used. Brief overview of CSP and existing CSP based libraries is given. Middleware architecture is proposed along with few novel ideas
Routing Protocols for Lossy Wireless Networks
Tato práce zkoumá vhodnost a poĹľadavky návrhu simulacĂ pro simulátor NS-3 pro pĹ™Ăpad bezdrátovĂ˝ch sĂtĂ pouĹľĂvanĂ˝ch v měřĂcĂ infrastruktuĹ™e spoleÄŤnosti Kamstrup. V práci je popsán simulátor NS-3 a je vytvoĹ™ena základnĂ implementace dvou protokolĹŻ. Wireless M-Bus jako pĹ™Ăklad jednosmÄ›rnĂ©ho protokolu pro zaĹ™ĂzenĂ napájenĂ© z bateriĂ. Simulace Wireless M-Bus je porovnána s daty naměřenĂ˝mi v reálnĂ©m systĂ©mu. NS-3 poskytuje flexibilnĂ prostĹ™edĂ pro vĂ˝voj simulacĂ rĹŻznĂ˝ch sĂĹĄovĂ˝ch protokolĹŻ, vÄŤetnÄ› tÄ›ch urÄŤenĂ˝ch pro sĂtÄ› inteligentnĂch měřidel.This thesis investigates suitability and design constraints of the NS-3 Simulator for simulations of wireless protocols used by Kamstrup metering infrastructure. An overview of NS-3 Simulator is given and preliminary implementations of two protocols are created. Wireless M-Bus as an example of a one-way protocol for battery-powered devices. The simulation of Wireless M-Bus is compared with measurements obtained in a real deployment. NS-3 proves to be a flexible framework for developing simulations of various network protocols, including the ones used for smart metering.
Data communication network at the ASRM facility
The main objective of the report is to present the overall communication network structure for the Advanced Solid Rocket Motor (ASRM) facility being built at Yellow Creek near Iuka, Mississippi. This report is compiled using information received from NASA/MSFC, LMSC, AAD, and RUST Inc. As per the information gathered, the overall network structure will have one logical FDDI ring acting as a backbone for the whole complex. The buildings will be grouped into two categories viz. manufacturing critical and manufacturing non-critical. The manufacturing critical buildings will be connected via FDDI to the Operational Information System (OIS) in the main computing center in B 1000. The manufacturing non-critical buildings will be connected by 10BASE-FL to the Business Information System (BIS) in the main computing center. The workcells will be connected to the Area Supervisory Computers (ASCs) through the nearest manufacturing critical hub and one of the OIS hubs. The network structure described in this report will be the basis for simulations to be carried out next year. The Comdisco's Block Oriented Network Simulator (BONeS) will be used for the network simulation. The main aim of the simulations will be to evaluate the loading of the OIS, the BIS, the ASCs, and the network links by the traffic generated by the workstations and workcells throughout the site
Applying Prolog to Develop Distributed Systems
Development of distributed systems is a difficult task. Declarative
programming techniques hold a promising potential for effectively supporting
programmer in this challenge. While Datalog-based languages have been actively
explored for programming distributed systems, Prolog received relatively little
attention in this application area so far. In this paper we present a
Prolog-based programming system, called DAHL, for the declarative development
of distributed systems. DAHL extends Prolog with an event-driven control
mechanism and built-in networking procedures. Our experimental evaluation using
a distributed hash-table data structure, a protocol for achieving Byzantine
fault tolerance, and a distributed software model checker - all implemented in
DAHL - indicates the viability of the approach
DNET: A communications facility for distributed heterogeneous computing
This document describes DNET, a heterogeneous data communications networking facility. DNET allows programs operating on hosts on dissimilar networks to communicate with one another without concern for computer hardware, network protocol, or operating system differences. The overall DNET network is defined as the collection of host machines/networks on which the DNET software is operating. Each underlying network is considered a DNET 'domain'. Data communications service is provided between any two processes on any two hosts on any of the networks (domains) that may be reached via DNET. DNET provides protocol transparent, reliable, streaming data transmission between hosts (restricted, initially to DECnet and TCP/IP networks). DNET also provides variable length datagram service with optional return receipts
IMITATOR II: A Tool for Solving the Good Parameters Problem in Timed Automata
We present here Imitator II, a new version of Imitator, a tool implementing
the "inverse method" for parametric timed automata: given a reference valuation
of the parameters, it synthesizes a constraint such that, for any valuation
satisfying this constraint, the system behaves the same as under the reference
valuation in terms of traces, i.e., alternating sequences of locations and
actions. Imitator II also implements the "behavioral cartography algorithm",
allowing us to solve the following good parameters problem: find a set of
valuations within a given bounded parametric domain for which the system
behaves well. We present new features and optimizations of the tool, and give
results of applications to various examples of asynchronous circuits and
communication protocols.Comment: In Proceedings INFINITY 2010, arXiv:1010.611
Creating the Virtual Library
Workshop presentation paper by Jules Winterton (Associate Director and Librarian, Institute of Advanced Legal Studies) providing an understanding of the key issues to be considered in creating and managing collections of electronic resources in libraries and some background to project design, funding and management
- …