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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.
201

Development and validation of Non-CODIS miniSTR genotyping systems suitable for forensic case work in South Africa

Abrahams, Zainonesa January 2010 (has links)
Magister Scientiae - MSc / The objective of this study was to develop and validate a six Non-CODIS miniSTR genotyping system and to determine its suitability for forensic casework in South Africa. In Non-CODIS miniSTR genotyping systems, smaller PCR products are amplified and the primers are positioned as close as possible to the repeat region. For this reason, these systems can be valuable in a variety of scenarios including complex paternity cases, missing persons work, and mass fatality disasters. / South Africa
202

Ekonomická analýza společnosti Budějovický Budvar, n. p. / Economic Analysis, Assessing of Financial Vitality by Various Methods

Herda, Pavel January 2013 (has links)
This master's thesis deals with economic analysis of Budweiser Budvar, NC. The aim of this analysis is to assess the economic situation of this brewery since 2007 to 2012. The basic principles and methods of economic analysis are explained in the theoretical part. It means especially methods of financial analysis, such as analysis of the balance sheet and profit and loss statement, financial ratios, economic value added or overall models of vitality of business. The particular economic analysis is performed in the practical part. It includes market analysis and comparison to main competitors. The thesis shows that the profitability of brewery Budweiser Budvar, NC, is below-average, especially if related to figures of its key competitors, on the other hand it is very stable and liquid company.
203

Obrábění odlitku převodovky na CNC stroji / Machining of the gear-box casting on a CNC machine

Hložek, Milan January 2018 (has links)
The master’s thesis focuses on the machining of a chosen gearbox on a CNC machine. The theoretical part deals with gearboxes in general and the aluminium alloy from which a selected gearbox is manufactured. In the practical part, the machining of the gearbox is proposed according to the corresponding drawing. Gradually suitable machines are selected, then depending on their limits, clamping devices are designed, next a set of tools is selected and an NC program is generated. The technological process of production is proposed and the basic production costs are calculated.
204

Návrh a realizace vylepšeného měřicího zařízení pro testování induktivních snímačů v klimatické komoře / Design and implementation of improved measuring device for inductive sensors testing in temperature chamber

Šimůnek, Patrik January 2020 (has links)
This thesis deals with the analysis of the measuring equipment for the testing of inductive sensors in the climatic chamber, which mainly highlights the faults and deficiencies of this device. Based on this analysis, a new measurement system is designed to eliminate these or all the deficiencies. Several new useful features are added to the new design of the measuring system.
205

Obrábění rotační součásti "těleso" na CNC soustruhu / Machining of rotating Body-part on CNC lathe

Dlouhý, Vít January 2020 (has links)
This master's thesis is focused on the technology fundamentals of machining for the use of the CNC lathe which was used for machining the required parts are made of stainless steel. In the introduction are mentioned the historical milestones related to machine tools. In the following chapter is analyzed machining process and related fact. A follow-up chapter contains the parameters common to a modern machine tool CNC machines. Followed by the practical part with the characteristics of the machined components. The next chapter includes a selection of CNC lathe for production. Continued by selecting the appropriate cutting tool and adjusting the machine for the given component. They were applied a total of three variants of production with the subsequent evaluation. In conclusion, it became established fact, for example, the advantages of the shape tools or the use of more spindles during the machining.
206

Optimalizace technologie součásti "nosná deska" ve firmě PROMAT Vsetín / Optimalization technology of production "nosná deska"-part in condition firm PROMAT Vsetín

Juráň, Jaromír January 2008 (has links)
Valorization and analysis of machining technology for the production of aluminium part and consecutively project optimization part production. New advanced cutting tools selection and application of new technologies. The adjustment and simplification of the existing NC program for given CNC machining centre and its final debugging. In the final part, there is an economical and technical evaluation of firm benefits and recommendations into production.
207

Technologie výroby součástky konzola / Technology of Production Parts Console

Rusník, Tomáš January 2011 (has links)
This thesis describes the complete technology solution of front driving axle console production by machining. The console is part of the self-supporting structure of the tractor and is produced under conditions of large engineering company. Introduction describes the prduction technology of component. The main part is devoted to the technological process of production and selection of appropriate cutting tools. Technical and economical evaluation of machined part is mentioned in the conclusion of thesis.
208

Racionalizace technologie výroby / Rationalisation of production technology

Konečný, Petr January 2014 (has links)
This thesis deals with the rationalization of production technology of selected component. The first part contains a brief introduction of the company NTS Prometal Machining s.r.o. and brief description of the product. The following section is an analysis of existing manufacturing technology. The practical part is focusing on the proposal of rationalization versions of the production process. After evaluation of all possible options of rationalization there has been developed a new technological process with a respect to time and cost savings. Finally there was carried out economical evaluation and recommendation for further production of this component.
209

Dimensionering av pelare och balkar i ett bostadshus med UHPC, respektive NC : En jämförelsestudie ur aspekten, en hållbar design

Persson, Axel, Rautjärvi, Rikhard January 2021 (has links)
It is a well-known problem that concrete needs to be made more efficient and that it is the large consumption of cement that is the major contributing factor to the nearby need. There is a zero vision of a climate-neutral concrete where all CO2 emissions in the life cycle of the concrete are to be reset by 2050. It is a question of improving, above all, the process of handling CO2 in the production of cement. This study tackles CO2 emissions from the concrete from a holistic perspective, by exploring optimization possibilities when implementing a newly developed concrete in residential buildings, called Ultra High Performance Concrete (UHPC). While it should be a better alternative for the climate, it should also require less material consumption and be more cost-effective in order to create a competitive alternative to the conventional alternative today, called Normal Concrete (NC). UHPC is during a development phase regarding optimization opportunities and it has been proven in several studies to be able to relate better to a sustainable design, based on a total life cycle progression. This applies above all to large and robust bridge structures where large volume differences are available. The idea behind this study is to highlight the question of whether there is an opportunity to get similar results in the construction of less robust components in residential buildings, since the problem with the mix design for UHPC has been the overall high cost in relation to NC. In recent years, this cost has been reduced and now there are opportunities to effectively introduce UHPC into another segment.In this study, columns and beams were dimensioned in a residential NC building and a residential UHPC building with ETABS (CSI 2019). Furthermore, the components of the buildings were compared, based on the aspect of a sustainable design from a total LCA. What was investigated were the differences in total material consumption, CO2 emissions, and costs.The study showed that the UHPC components were better based on all aspects after its total LCA. The total cement consumption was larger, but the building received at the same time an estimated double the lifespan of the NC- building. The total material consumption in the form of total component volumes became smaller, the total annual CO2 emissions became smaller and the total annual costs became smaller as well. / Det är ett välkänt problem att betong behöver klimateffektiviseras och att det är den storacementkonsumtionen som är den stora bidragande faktorn till det närliggande behovet. Detfinns en nollvision om en klimatneutral betong där alla CO2- utsläpp under betongenslivscykel (LCA), ska nollställas fram till år 2050. Det är en fråga om att framför allt förbättraprocessen gällande hantering av CO2 vid produktion av cement. Den här studien angriperCO2- utsläppen från betongen ur ett helhetsperspektiv, genom att undersökaoptimeringsmöjligheter vid implementering av en nyutvecklad betong i bostadshus, kalladUltra High Performance Concrete (UHPC). Samtidigt som den ska vara ett bättre alternativför klimatet, ska den också kräva mindre materialåtgång och vara mer kostnadseffektiv föratt kunna skapa ett konkurrenskraftigt alternativ till det konventionella alternativet idag,kallad Normal Concrete (NC). UHPC är under en optimeringsfas och den har bevisats i flerastudier kunna förhålla sig bättre till en hållbar design, utifrån en total LCA. Det gäller framförallt stora och robusta brokonstruktioner där stora volymskillnader är disponibla. Tankenmed den här studien är att lyfta fram frågan om det finns möjlighet att få liknande resultatvid byggnation av mindre robusta komponenter i bostadshus, i ju med att problemet medmix-designen för UHPC, har varit den generella höga kostnaden i förhållande till NC. Påsenare år har den kostnaden kunnat reduceras och nu finns möjligheterna att effektivtkunna införa UHPC till ytterligare ett segment.I studien jämfördes pelare och balkar i ett UHPC- hus med motsvarande komponenter i ettNC- hus utifrån aspekten en hållbar design, ur en total LCA. Husen dimensionerades i ETABS(CSI 2019) utefter samma förutsättningar med hänsyn till kravet på bärförförmågorna. Detutgjorde skillnader hos volymerna på komponenterna, som således påvisade hurmaterialåtgången förändrades. CO2- utsläppen och kostnaderna påverkades avbetongkompositionerna och skillnaderna hos de materiella egenskaperna av respektivebetongtyp. I slutändan redovisades vilken betongtyp som genererade minsta och störstaårliga CO2- utsläpp och kostnader.Resultatet visade att UHPC- komponenterna minskade den totala betongåtgången underbyggprocessen med 27,1%, samt minskade armeringsåtgången med 12,0%, men attcementåtgången nästan fördubblades och motsvarade en ökning på 99,4%. CO2- utsläppenvart således betydligt större efter byggprocessen, men i förhållande till ett totaltlivcykelförlopp, minskade de totala årliga utsläppen med 18,8%. Det fanns en kritisk punktdär UHPC- komponenterna måste ha en LCA på minst 97,5 år i förhållande till NCkomponenternas LCA på 60 år, för att vara mer lönsamma utifrån totala CO2- utsläpp.Kostnaderna vart också betydligt större för UHPC- komponenterna efter byggprocessen,men efter en total LCA, minskade de totala kostnaderna med 39,0%. Det fanns en kritiskpunkt, där LCA- förloppet måste uppgå till minst 73,2 år i förhållande till NCkomponenternas LCA på 60 år, för att vara mer lönsamma utifrån totala kostnader.Enligt det framtagna resultatet fanns det goda möjligheter för pelare och balkar i UHPChuset att förhålla sig bättre utifrån en hållbar design, än vad motsvarande komponenter förNC- huset gjorde, efter en total LCA. Pelare och balkar i bostadshus kan bli ett nytt segmentatt introducera UHPC till, även om pålitligheten för studien är begränsad av betydelsefullafelkällor och tillgängliga kunskaper inom området för närvarande.
210

Interferometric detection and control of cantilever displacement in NC-AFM applications

von Schmidsfeld, Alexander 11 July 2016 (has links)
The interferometric cantilever displacement detection in non-contact atomic force microscopy (NC-AFM) is in fundamental aspects explored and optimized. Furthermore, the opto-mechanical interaction of the light field with the cantilever is investigated in detail. Cantilevers are harmonic oscillators that are designed to have a high sensitivity for the detection of minute external forces typically originating from tip-sample interaction. In this work, however, the high sensitivity is used for detailed studies of opto-mechanical forces due to the radiation pressure of the light interacting with the cantilever. The interferometer in the NC-AFM setup consists of an optical cavity working similar to a Fabry-Pérot interferometer in combination with a reference interference arm working similar to a Michelson interferometer combining multi-beam interference with a reference beam resulting in a complex superposition of beams forming the interferometric intensity modulation signal. The character of the interferometer can be adjusted from predominant Michelson to predominant Fabry-Pérot characteristics by the optical loss inside the cavity. A systematic approach for accurate alignment, by using 3D intensity maps and intensity-over-distance curves, as well as the implications of deficient fiber-cantilever configurations are explored and the impact of the interferometer configuration on the detection system noise floor is investigated. A new physical property, namely, the Fabry-Perot enhancement factor is introduced that is a direct measure for the light intensity interacting with the cantilever compared to the reference beam intensity reflected back inside the fiber. The quantification of the optical loss yields an exact knowledge of the amount of light interacting with the cantilever that is crucial to understand opto-mechanical effects. The resulting opto-mechanical force varies sinusoidally during the course of one oscillation cycle. It is a key result of this work that the sinusoidal modification of the cantilever restoring force can be described analogue to the restoring force of a pendulum. This results in an observable amplitude dependent frequency shift of the cantilever oscillation, allowing a calculation of the ratio of the opto-mechanical force relative to the cantilever restoring force and thus allows an in-situ measurement of the cantilever stiffness with remarkable precision. Further investigation of the cantilever oscillation yields that other characteristic properties of the oscillation are significantly modified by the opto-mechanical interaction. The observed effective fundamental mode Q-factor drops significantly while the cantilever amplitude response to a certain excitation voltage increases. A discrete numerical model describing the cantilever as a 1D linear chain of mass points is implemented, yielding that the additional opto-mechanical force results in a partial pinning of the cantilever at the edges of the interferometric fringes. Pinning efficiently shifts energy from the fundamental mode to higher modes and modes of a pinned cantilever, resulting in a complex modal structure.

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