• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 45
  • 43
  • 30
  • 28
  • 12
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 171
  • 31
  • 27
  • 25
  • 24
  • 21
  • 19
  • 16
  • 16
  • 16
  • 15
  • 15
  • 14
  • 13
  • 13
  • 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.
1

New control systems for aging SIEMENS cyclotrons

Playle, D. D. 19 May 2015 (has links) (PDF)
Introduction When properly maintained, cyclotrons often remain in operation for 20 years and more. However, as the years pass the control systems in particular become challenging to support. The I/O cards and other hardware eventually become obsolete, making spare parts difficult or even impossible to find. And the knowledge and ability to reload and configure the software also gets lost as operating systems and media storage technology change. This obsolescence is true of the Siemens RDS-112 cyclotron, which is controlled using a 486 computer, connected to an external STD card rack containing up to 15 I/O cards. These I/O cards were last manufactured in the 1990’s, and the iRMX-based control programs malfunction on computers newer than a 486 processor. A control system upgrade for the RDS-112 cyclotron has been developed by PET Technical Consulting Inc. This commercially available control system reduces operator training time, requires less maintenance, and supports new targets and custom product processes. Material and Methods The availability of high channel count I/O cards, and the decision not to support the old CPCU synthesis units, means the entire STD card rack can be replaced with 5 National Instruments (NI) I/O cards. The replacement computer is an industrial grade rack mounted PC with RAID 1 mirrored pair hard drives in front panel access quick swap bays. Two NI PCI-6509 Digital I/O cards connect directly to the RDS electronics, channel assignments are mapped using software configuration. Three NI PCI-6229 Multifunction I/O cards connect to the RDS electronics through a cable breakout interface plate, the terminal blocks are wired as needed to map the channels. The new control software was created using National Instruments LabVIEW. The new control sequences have a core based on the original RDS-112 FORTRAN control programs. Then hundreds of improvements were made to simplify operation, increase flexibility, minimize user involvement and mistakes, and clearly display key parameters and fault conditions. System control has been combined into a comprehensive Graphical User Interface, with controls and indicators grouped together onto subsystem pages. Commands that once needed to be typed-in have been replaced with a clickable control for each function. Bar graphs display target and slit currents. Status is obvious with red faults against normally green indicators. Audio alarms cue the operator for process interaction, warn if target current or pressure drifts from setpoint, or if faults occur with power supplies, vacuum, or water cooling. Improvements in sequences and beam algorithms have reduced the time to achieve full beam on dual targets from 10 minutes down to 3 minutes. Results and Conclusion This new control system has been installed on (5) five RDS-112 cyclotrons used for commercial isotope distribution. The total combined operation time of these systems after receiving the upgrade is now over 17 years, during this time the control system operation has been nearly problem free. UPDATE: The Siemens RDS-111 cyclotron is controlled by a VME computer that is now end-of-life. The VM30 and VM42 CPU boards and many of the I/O modules are no longer manu-factured. PET Technical Consulting is developing a control system replacement for the RDS-111 cyclotron with expected completion in 2014.
2

Entwicklung und Tätigkeit der Firma Siemens & Halske in den Jahren 1847-1897

Winterfeld, Ludwig von, January 1913 (has links)
Inaug.-Diss.--Kiel. / Vita. Bibliography: p. [141]-142.
3

Siemens in Argentinien : die Unternehmensentwicklung vom Markteintritt bis zur Enteignung 1945 /

Rennicke, Stefan. January 1900 (has links)
Diss.--Köln--Universität, 2004.
4

Vom Trommelwähler zu Optiset E die Geschichte der drahtgebundenen Telefone für die Wählnebenstellenanlagen von Siemens (1950 - 2000)

Arbenz, Dietrich January 2009 (has links)
Zugl.: Düsseldorf, Univ., Diss., 2009
5

Siemens, André und das Reichspatentgesetz aus der Sicht des Siemens Historical Institute

Kiuntke, Florian 20 June 2011 (has links) (PDF)
Der Vortrag beleuchtet die Zusammenarbeit von Werner von Siemens mit Wilhelm André im Vorfeld des Reichspatentgesetzes 1877. / The lecture covers the cooperation between Werner von Siemens and Wilhelm André in the run-up to the formal proclamation of the first uniform German Patent Act as “Reichspatentgesetz” in 1877.
6

Siemens und die Sowjetunion nach dem Ersten Weltkrieg

Lutz, Martin. January 2004 (has links)
Konstanz, Univ., Magisterarbeit, 2004.
7

Managing diversity am Beispiel von gender politics Frauen und Karriere bei Siemens

Fischer, Eva January 2004 (has links)
Passau, Univ., Diss., 2004
8

Integration av konstruktionsdatabas och styrsystem

Söderhielm, Kristofer January 2012 (has links)
The Mission at ÅF Industry in Norrkoping was about optimizing bulk data handling while importing process tag types from their construction database into the Process Controlled System of type Siemens PCS7.I found three different methods to solve the task. Two of them were using different software from Siemens under the premise that the report from the database was corrected as needed. The third variant was manually creating the circuits. All methods worked out fine but there were times when one was better than another.To solve this task I had access to all software presented in chapter 2 “Programvara” (=Software). I also had a close cooperative with employers at ÅF that works with the system today and also with personal att Siemens AG in Germany and Sweden.
9

Optimering av formmaskin M01

Olsson, David January 2014 (has links)
Detta examensarbete på 22,5 hp är en del av mekatronikingenjörsutbildningen vid Karlstads universitet. Uppdragsgivaren är Valmet AB (tidigare Metso AB) i Hagfors som tillverkar och säljer malsegmentslitdelar för pappersindustri och massaindustri.Projektet behandlar en av de tre formmaskiner som finns på företaget, kallad M01. Formningsmomentet är grunden till gjutresultatet av produkterna och i dagsläget är det för stora variationer på kvalitetsutfall, delvis orsakat av för många frihetsgrader i hur maskinen opereras. Målet är att komma fram till en automatiserad lösning av utstötning av skalhalvor, hålla en jämnare nivå i sandkassen genom nivåmätning samt minska spill vid påfyllningen av sand.En tryckvakt och en ultraljudsgivare användes för att kunna mäta maskinens tillstånd och som styrning användes en extern PLC, Siemens LOGO! utöver den ordinarie PLC:n som används.Resultatet blev en prototyp som tillsammans med ett antal nya sensorer kan göra testmätningar och tillfälligt styra maskinen för att få en anvisning om det kan vara en bra lösning i framtiden. Lösningen ska senare kunna utvecklas fullt ut med bättre sensorer och dess funktioner ska kunna implementeras i den ordinarie PLC:n för att användas i samtliga formmaskiner.Alla lösningar fick inte fullt önskvärt resultat men de är ändå ett steg i rätt riktning. Skalen släpper inte lättare men en automatiserad utstötningsfunktion har tagits fram och kan användas som ett komplement för att underlätta för operatören. Lösningen har även lett till att det har blivit minskat spill samt att tiden för sandpåfyllning numera kan styras genom nivåmätning. Dock måste den startas manuellt i varje tillverkningscykel. / This degree project of 22.5 hp is part of the Mechatronics Engineering education at Karlstad University. The client is Valmet AB (formerly Metso AB) in Hagfors, which manufactures and sells grinding segments for the paper and pulp industry.The project highlights one of the three formwork machines at the company, called M01. The formwork is the basis to the molding results of the products and in the current situation it is of great variability in quality outcomes, partly caused by too many degrees of freedom in how the machine operated. The goal is to come up with an automated solution for ejection of shell halves, maintain a more stable level of sand in the sandbag through level measurements and reduce spillage during filling of sand.A pressure sensor and an ultrasonic sensor have been used to measure the state of the machine and to control an external PLC, Siemens LOGO addition to the ordinary PLC has used.The result was a prototype that together with a number of new sensors can make test measurements and temporarily control the machine to get a hint about if it could be a good solution in the future. The solution could later be fully developed with better sensors and its features implemented into the regular PLC to be used in any formmachine.All the solutions were not fully desirable but they are still a step in the right direction. The shells doesn’t let go easier but an automated ejection program has been developed and that be used as a supplement and assist the operator. The new solution has also led to reduced waste, and that the time for sand filling is now controlled through level measurements. However, it must be started manually in each production cycle.
10

Rationalisierung und Industriearbeit : Arbeitsmarkt, Management, Arbeiterschaft im Siemens-Konzern Berlin 1900-1939 /

Homburg, Heidrun, January 1991 (has links)
Texte remanié de: Diss.--Fakultät für Geschichtswissenschaft und Philosophie--Universität Bielefeld, 1982. Titre de soutenance : Arbeitsmarkt und Organisation: Arbeitsmarktstruktur, Gewerkschaften und Unternehmen in der Berliner Metallindustrie, 1890-1933. / Bibliogr. p. 719-776. Index.

Page generated in 0.0466 seconds