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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.
471

Oförsvarbart : argumentationen i media rörande Försvarsmaktens avveckling av överskott 2000-2003 / Discourse analysis of media argumentation concerning swedish military surplus 2000-2003

Magnusson, Melker January 2003 (has links)
The Swedish Military Defence is about to make a large reorganization. Surplus, everything from tanks to personal underwear, enough to equip 800,000 soldiers will be destroyed or sold to the highest bidder. This thesis is a discourse analysis about the argumentation in media between the Military and the enthusiast, who are interested in military vehicles and military surplus. / Uppsatsen är en kartläggning och diskursanalys av den argumentation som förekommit i den mediala debatten rörande den svenska Försvarsmaktens avveckling av överskott. Morgondagens försvar ska vara baserat på kvalité istället för kvantitet. Från att ha haft ett försvar som omfattat omkring 800 000 personer under vapen i händelse av ofred ska det nya försvaret skäras ned till att omfatta omkring 200 000 personer. En mängd materiel, allt från stridsvagnar och underkläder, blir således överflödig. Försvarsmakten skall fram till utgången av 2004 ha genomfört omorganisationen. Tillvägagångssättet att avveckla överskottet varierar, destruktion, försäljning och som bistånd är exempel på avvecklingsalternativ. De olika tillvägagångssätten har fått kritik från olika aktörer som deltagit i debatten. Det opinionen reagerat på är att, i många fall, helt fungerande och ny materiel destruerats eller så har kritik riktats mot de olika försäljningsförfarandena som Försvarsmakten tillämpat. Uppsatsen undersöker aktörernas argumentering i debatten och försöker att analysera varför argumenteringen ser ut som den gör.
472

High performance DSP-based servo drive control for a limited-angle torque motor

Zhang, Yi January 1997 (has links)
This thesis describes the analysis, design and implementation of a high performance DSP-based servo drive for a limited-angle torque motor used in thermal imaging applications. A limited-angle torque motor is an electromagnetic actuator based on the Laws' relay principle, and in the present application the rotation required was from - 10° to + 10° in 16 ms, with a flyback period of 4 ms. To ensure good quality picture reproduction, an exceptionally high linearity of ±0.02 ° was necessary throughout the forward sweep. In addition, the drive voltage to the exciting winding of the motor should be less than the +35 V ceiling of the drive amplifier. A research survey shows that little literature was available, probably due to the commercial sensitivity of many of the applications for torque motors. A detailed mathematical model of the motor drive, including high-order linear dynamics and the significant nonlinear characteristics, was developed to provide an insight into the overall system behaviour. The proposed control scheme uses a multicompensator, multi-loop linear controller, to reshape substantially the motor response characteristic, with a non-linear adaptive gain-scheduled controller to compensate effectively for the nonlinear variations of the motor parameters. The scheme demonstrates that a demanding nonlinear control system may be conveniently analysed and synthesised using frequency-domain methods, and that the design techniques may be reliably applied to similar electro-mechanical systems required to track a repetitive waveform. A prototype drive system was designed, constructed and tested during the course of the research. The drive system comprises a DSP-based digital controller, a linear power amplifier and the feedback signal conditioning circuit necessary for the closed-loop control. A switch-mode amplifier was also built, evaluated and compared with the linear amplifier. It was shown that the overall performance of the linear amplifier was superior to that of the switch-mode amplifier for the present application. The control software was developed using the structured programming method, with the continuous controller converted to digital form using the bilinear transform. The 6- operator was used rather than the z-operator, since it is more advantageous for high speed sampling systems. The gain-scheduled control was implemented by developing a schedule table, which is controlled by the DSP program to update continuously the controller parameters in synchronism with the periodic scanning of the motor. The experimental results show excellent agreement with the simulated results, with linearity of ±0.05 ° achieved throughout the forward sweep. Although this did not quite meet the very demanding specifications due to the limitations of the experimental drive system, it clearly demonstrates the effectiveness of the proposed control scheme. The discrepancies between simulated and experimental results are analyzed and discussed, the control design method is reviewed, and detailed suggestions are presented for further work which may improve the drive performance.
473

Analýza organizační kultury v dopravní společnosti / Analysis of the organizational culture of transport company

Kučerová, Eliška January 2016 (has links)
The aim of the thesis is to analyse the organizational culture in three local companies of the transport corporation. The analysis is carried out with the aim to map the organizational culture in the local companies. At the beginning of the work is described theory, which is composed from the organizational culture, models of individual organizational cultures and elements that may affect the strength of the organizational culture and others. In the empirical part are analysed the data obtained by various methods of diagnostics organizational culture. These include observation, interviewing and analysis the documents of company. At the end of this thesis are found the recommendations for the company.
474

Motokolo se spalovacím motorem a elektrickým přenosem výkonu / Bycicle with Combustion Engine and Electrical Transfer of Power

Mazálek, Tomáš January 2017 (has links)
The objective of this semester thesis is design of the control algorithm, needed control and power circuits and PCB design for the unfinished bicycle concept with a combustion engine and electric power transmission. The control algorithm had to be designed to make efficient use of the combustion engine performance and to minimalize the fuel consumption and noise level of the device. All circuits are fully implemented by analog components for which were designed printed circuit boards using program Eagle and this boards were revived and debugged.
475

Vzdálené školící pracoviště / Remote training station

Kučera, Tomáš January 2019 (has links)
The purpose of the thesis is design and contruction of remote training station for training with Schneider Electric products. Its purpose is to introduce company PLCs, familirize user with configuring variable speed drives and servo drives and prezenting Machine Advisor and EcoStruxure Augmented Operator Advisor online servives The begining is dedicated to introduction to company and a range of its products in the field of industrial automation. In second chapter, I select components for building training station. Third chapter is dedicated to assembly of station. In fourth chaper I describe programing of individual elements and example.
476

Simulační modely elektrických pohonů vozidel / Simulation models of electric drive vehicles

Bílý, Lukáš January 2011 (has links)
The work deals with creating a DC electric motor drive. The model is composed of electrical power from the engine model and transistor pulse converter load, which are joined together and completed the anchor and regulate the flow control engine speed. Great attention was paid to the determination of losses in the load drive electric vehicles and create a model of electric power load. The real work was verified by an experimental model of an electric vehicle Car4 the available parameters.
477

Zkušební pracoviště synchronních generátorů / Testing stand of synchronous machines

Král, Michal January 2015 (has links)
This diploma thesis deals with a part of synchronous generator testing stand project. Thesis is focused on drive part of testing stand, the appropriate drive is chosen according to type of the tests. The attention is mainly on drive control, specifically on the configuration of frequency converter and software programming of the converter control in NI LabVIEW. Software also contains drive simulation program. Testing stands are sequentially installed and commissioned.
478

Jízdní kolo s elektrickým motorem a benzinovou elektrocentrálou / Electric bike with a combustion-engine-powered generator

Mička, Dominik January 2015 (has links)
A conceptual design and realization of a motor bike using combustion engine and electrical power transfer is the objective of this master´s thesis. Control strategy that allows combustion engine to reach maximal efficiency cooperating with wide range speed and torque operating area electromotor was created. All function blocks were realized. Also hardware of all needed parts was developed. The last part was a design and debugging of control software. Finally the functionality was documented by test drives and measurements.
479

Modulární řešení válečkového dopravníku / Modular concept of roller conveyor system

Novotný, Lukáš January 2009 (has links)
This diploma thesis is dealing with the modular project of a roller conveyer track for transport of europallets with the loading limit of 1200 kg and its use in practise. There are also mentioned possible construction solutions and the actual construction project. It is followed by calculating and modular project of direkt conveyer. Further on, I am dealing with the project of a sliding turntable of cable loops and surfaře covering. In the conclusion, I think out the problems of sensors and a possible operating conveyer.
480

Design dálkového autobusu / Design of transit bus

Semerák, Jan January 2010 (has links)
The diplom work is focused on the design of transit bus. I pointed out two aim: design from the view of future the perspektive; environmental drive and create timeless bus design, which should be correspond with the drive of near future. It was chosen the most ecological drive with help of hydrogen and fuel cells. This drive was developed in detail. Like reserve and helpful energy source was used ultrakapacitors and fotovoltaic cells. Bus design tries to realize the future requirement of carriers and regarding to its oscillating along big cities so represent with its design the used drived unit. The internal ordering of interior tries to realize the together and future reguirements on the sit ergonomics, store of bagages, hygienic requirements and good lookout of passengers. The name and logo of transit bus arrise from reference to fuell, environment and fuell cell.

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