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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Intelligent Control of Vehicle-Based Internal Transport Systems

Le Ahn, Tuan. January 2005 (has links)
Proefschrift Erasmus Universiteit Rotterdam.
182

Kennwertorientierte Methoden zur Auswahl und Synthese von Bewegungsgesetzen für Motion-Control-Systeme

Speicher, Thorsten 04 October 2021 (has links)
Im Rahmen dieser Arbeit werden Methoden präsentiert, die Anwender bei der Auslegung von taktzeitoptimalen Bewegungen für typische Rast-in-Rast-Charakteristiken unter Verwendung von normierten Bewegungsgesetzen nach der VDI-Richtlinie 2143 unterstützen. Es wird eine Herangehensweise vorgestellt, die bei Vorgabe von kinematischen Bewegungsgrenzen zu verwenden ist. Führt dabei die resultierende Bewegung zu einer unzulässigen Erwärmung des Antriebs, lässt sich mit Hilfe anderer Werkzeuge die minimal mögliche und somit optimale Taktzeit effizient bestimmen.:1 Einleitung 2 Stand der Forschung 3 Grundlagen 4 Taktzeitoptimierung bei kinematischen Restriktionen 5 Taktzeitoptimierung bei thermischen Restriktionen 6 Anwendungsbeispiele 7 Zusammenfassung und Ausblick / This paper presents methods to help users design motions with ideal cycle times for rest in rest applications by using the normalized laws of motion according to the VDI guideline 2143. The approach shown is used for systems that are limited by their kinematic parameters. If the resulting movement leads to inadmissible heating of the drive, other tools are able to determine the minimal cycle time considering the thermal limit.:1 Einleitung 2 Stand der Forschung 3 Grundlagen 4 Taktzeitoptimierung bei kinematischen Restriktionen 5 Taktzeitoptimierung bei thermischen Restriktionen 6 Anwendungsbeispiele 7 Zusammenfassung und Ausblick
183

SELF-OPTIMIZATION SYSTEMS DESIGN BASED ON SLIDING MODE CONTROL

Cakanel, Ahmet January 2017 (has links)
No description available.
184

Flexible role-handling in command and control systems

Landberg, Fredrik January 2006 (has links)
<p>In organizations the permissions a member has is not decided by their person, but by their functions within the organization. This is also the approach taken within military command and control systems. Military operations are often characterized by frictions and uncontrollable factors. People being absent when needed are one such problem.</p><p>This thesis has examined how roles are handled in three Swedish command and control systems. The result is a model for handling vacant roles with the possibility, in some situations, to override ordinary rules.</p>
185

Flexible role-handling in command and control systems

Landberg, Fredrik January 2006 (has links)
In organizations the permissions a member has is not decided by their person, but by their functions within the organization. This is also the approach taken within military command and control systems. Military operations are often characterized by frictions and uncontrollable factors. People being absent when needed are one such problem. This thesis has examined how roles are handled in three Swedish command and control systems. The result is a model for handling vacant roles with the possibility, in some situations, to override ordinary rules.
186

THE NEXT GENERATION AIRBORNE DATA ACQUISITION SYSTEMS PART II – SPECIFICATION, TRADE-OFFS AND SOME LESSONS LEARNED

Sweeney, Paul 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The advent of a new generation of analog to digital converters (ADC’s) provides the aerospace signal-conditioning engineer with many design advantages, trade-offs and challenges for their next generation of signal conditioning systems. These advantages include increased range, resolution, accuracy, channel-count and sampling rate. However, in order to capitalize on these advantages, it is important to understand the trade-offs involved and to specify these systems correctly. Trade-offs include: • Analog vs. Digital signal conditioning • Implementation issues such as 12-bits vs. 16-bits (or even 24-bits) • Topology issues such as multiplexers vs. multiple ADC’s • Filter-type selection • Sigma-Delta vs. Successive Approximation ADC’s. Specification challenges include: • Total DC error vs. gain and offset (and drift, excitation, DNL, crosstalk, etc.) • ENOB vs. SINAD (or THD, SNR or Noise) • Coherency issues such as filter phase distortion vs. delay This paper will discuss some of these aspects and attempts to produce a succinct specification for the next generation of airborne signal conditioning, while also outlining some of the lessons learned in developing the same.
187

THE NEXT GENERATION AIRBORNE DATA ACQUISITION SYSTEMS. PART 1 - ANTI-ALIASING FILTERS: CHOICES AND SOME LESSONS LEARNED

Sweeney, Paul 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The drive towards higher accuracy and sampling rates has raised the bar for modern FTI signal conditioning. This paper focuses on the issue of anti-alias filtering. Today's 16-bit (and greater resolution) ADC’s, coupled with the drive for optimum sampling rates, means that filters have to be more accurate and yet more flexible than ever before. However, in order to take full advantage of these advances, it is important to understand the trade-offs involved and to correctly specify the system filtering requirements. Trade-offs focus on: • Analog vs. Digital signal conditioning • FIR vs. IIR Digital Filters • Signal bandwidth vs. Sampling rate • Coherency issues such as filter phase distortion vs. delay This paper will discuss each of these aspects. In particular, it will focus on some of the advantages of digital filtering various analog filter techniques. This paper will also look at some ideas for specifying filter cut-off and characteristics.
188

The Implications for Network Recorder Design in a Networked Flight Test Instrumentation Data Acquisition System

Cranley, Nikki 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / The higher bandwidth capacities available with the adoption of Ethernet technology for networked FTI data acquisition systems enable more data to be acquired. However, this puts increased demands on the network recorder to be able to support such data rates. During any given flight, the network recorder may log hundreds of GigaBytes of data, which must be processed and analyzed in real-time or in post-flight. This paper describes several approaches that may be adopted to facilitate data-on-demand data mining and data reduction operations. In particular, the use of filtering and indexing techniques that may be adopted to address this challenge are described.
189

Vérification formelle et Simulation pour la Validation du système de contrôle commande des EALE (Équipements d'Alimentation des Lignes Électrifiées) / Formal verification and simulation for the validation of PSEEL's control systems (Power Supply Equipment of the Electric Lines)

Niang, Mohamed 20 December 2018 (has links)
La SNCF cherche à mettre en place des solutions innovantes permettant d’améliorer la sécurité et les conditions de travail des chargés d’études lors des travaux d’automatisation. En partant de l’étude théorique du projet jusqu’à sa validation sur site, en passant par la mise en œuvre des programmes, du câblage des armoires, et de leur vérification sur plateforme et en usine, ces différentes tâches s’avèrent souvent être longues, complexes, et répétitives, ce qui a pour effet d’augmenter la charge de travail des chargés d’études. En vue d’améliorer les conditions de travail des chargés d’études, ce projet de recherche vise principalement à améliorer leurs méthodologies de vérification des programmes API (aspects fonctionnels et sécuritaires) et du câblage des armoires électriques. Ce projet intitulé « Vérification formelle et simulation pour la validation des programmes API des EALE » se décompose en deux axes :  la vérification hors ligne des programmes API : basée sur une approche formelle, la méthode s’appuie sur une modélisation de l’installation électrique, des programmes API et du cahier de recette dans le model-checker Uppaal. Le principe consiste à vérifier automatiquement si les programmes satisfont aux tests du cahier de recette.  la vérification en ligne du câblage des armoires de contrôle/commande/ protection grâce à un simulateur de partie opérative interfacé avec les armoires de contrôle/commande/protection (via une armoire de test). La vérification se fera de manière automatique et en ligne, toujours avec les tests du cahier de recette, et permettra de valider le câblage des armoires et les réglages des appareils de protection numérique. / In order to keep its leadership in French rail market and to improve working conditions of its systems engineers during automation projects, the SNCF (French acronym for National Society of French Railways) wants to develop solutions increasing the productivity. One of these improvements focuses on the current methodology used by the systems engineers to verify and validate the control command system of electrical installations. This task remains one of the most important during an automation project because it is supposed to ensure installations safety, but it should be optimized. Through an industrial thesis financed by SNCF, the aim of this research project is to improve this method and reduce time validation of control command system by providing tools which will help systems engineers to verify and validate quickly and automatically the control command system during any automation project. It is composed of two axes : - Offline verification of PLC programs with model checking - Online validation of electrical cabinets with virtual commissioning
190

Testsystem för processtyring / Test system for process control

Rust, Josefine January 2017 (has links)
Målet med det här arbetet var att implementera och bygga ett komplett testsystem för reglering som efterfrågades av företaget Prevas AB i Karlstad. De önskade ett testsystem som reglerar en vattentemperatur som de kan använda på kontoret för att genomföra egna tester, analyser samt lära nyanställda medarbetare mer om automation. Testsystemet har även ett tillhörande HMI (Machine Human Interface) som användaren styr regleringen ifrån. Regleringen i testsystemet använder PID(Proportional–integral–derivative)-reglering och är inställd med lambdametoden. PID-reglering är den vanligaste använda metoden inom tillverkningsindustrin för reglering, men trots det är det många av dagens PID-regleringar som underpresterar. En anledning är slitage i mekaniska ställdonen som finns i processerna. För att utvärdera att testsystemet fungerar samt för att visa vad det kan användas till, har en mindre analys av ett mekaniskt ställdon genomförts, där antalet tillslag för ett ställdon i det byggda systemet undersökts. Testsystemet som byggdes uppfyller de krav som ställts från Prevas och de är nöjda med resultatet. Analysen som genomfördes visade att testsystemet fungerade och kan användas till den typen av test. Analysen i sig visade att simulationen som implementerats i testsystemet inte fungerade som den skulle och därmed är några testresultat ogiltiga. Rapporten presenterar hur ett testsystem för reglering kan implementeras och sedan vad det kan användas till.

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