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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.
61

Erste Erfahrungen mit der Micro-Diagonalpumpe Deltastream® der Firma Medos (Helmholtz Institut Aachen) als linksventrikulärem Herzunterstützungssystem (LVAD) mit pulsatiler und laminarer Perfusion am Schafsmodell über sieben Tage. / Initial experience with the Micro Diagonal Pump Deltastream® of Medos, (Helmholtz Institute Aachen) a left ventricular cardiac assist device (LVAD) with pulsatile and laminar perfusion in a sheep about seven days.

Tylla, Alfred 09 January 2012 (has links)
No description available.
62

Průmyslové čerpadlo s integrovaným elektromagnetickým systémem / Industrial Pump with Electromagnetic System

Pazdera, Ivo January 2013 (has links)
This work is focused on innovative construction of the industrial radial sealless pump and mainly on construction of the three phase DC/AC converter based on new semiconductor technology SiC. These new semiconductor devices allow move switching frequency up to 100 kHz. For such high switching frequency new non-conventional topology of the output filter was designed. This high frequency is currently unusual in three-phase application with output voltage 400V. High switching frequency reduces size of wound components of the output filter and its presence is accepted in terms of total weight and price of the whole system. Clear sinus waveform of the output converter voltage reduces torque ripple, EMC and extend the lifetime and reliability of mechanical parts and the whole pump drive. Three phase synchronous motor is directly placed into the pump body and is designed as slotless motor. In the inlet area is the classical bearing replaced by active magnetic bearing. It is used due to possibility to pump aggressive liquids or substances where high level of cleanness has to be guaranteed.
63

Innovative twisting mechanism based on superconducting technology in a ring-spinning system

Hossain, Mahmud, Abdkader, Anwar, Cherif, Chokri, Sparing, Maria, Berger, Dietmar, Fuchs, Günter, Schultz, Ludwig 17 September 2019 (has links)
Twist plays an important role to impart tensile strength in yarn during the spinning process. In the most widely used ring-spinning machine for short staple yarn production, a combination of ring and traveler is used for inserting twist and winding the yarn on cops. The main limitation of this twisting mechanism is the friction between the ring and traveler, which generates heat at higher speed and limits the productivity. This limitation can be overcome by the implementation of a magnetic bearing system based on superconducting technology, which replaces completely the existing ring/traveler system of the ring-spinning machine. This superconducting magnet bearing consists of a circular superconductor and permanent magnet ring. After cooling the superconductor below its transition temperature, the permanent magnet ring levitates and is free to rotate above the superconductor ring according to the principles of superconducting levitation and pinning. Thus the superconducting magnetic bearing (SMB) ensures a friction-free operation during spinning and allows one to increase spindle speed and productivity drastically. The yarn properties using the SMB system have also been investigated and they remain nearly identical to those of conventional ring yarns.

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