• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 21
  • 20
  • 11
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 75
  • 43
  • 23
  • 14
  • 13
  • 11
  • 11
  • 10
  • 9
  • 8
  • 8
  • 7
  • 7
  • 7
  • 7
  • 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

Most přes údolí potoka Kyselá voda / Bridge over the Kyselá voda brook valley

Svoboda, Tomáš January 2015 (has links)
The subject of the diploma thesis is the design of the ghrinder bridge over the Kyselá voda brook valley. The main topic is static calculation of supporting construction of six span structure. Two studies were executed and the second option, pre-stressed girder bridge was chosen. The lenght of the spans is 27 + 6 x 35 + 27 m. Static model and effect of loading are solved in software Scia Engineer. Reviews are calculated by hand according to current standards.
62

Aplikace vstřikovacího systému s tlakovým zásobníkem na vznětový šestiválcový motor / Application of Pressure Accumulator Injection System on Six-cylinder CI Engine

Pacovský, Tomáš January 2011 (has links)
This master's thesis deals with application of modern injection system Common Rail on six-cylinder CI engine. One of aims of thesis is to get a large overview of pressure accumulator injection system and explore the development in this area. Among main aims of the thesis belong a new construction layout in Pro/Engineer, accomplishing of static and dynamic analyse of most important parts via the finite element method (FME) and necessary control calculations. Finally, the design documentation of new most essential designed parts will be made. During making the thesis necessary source materials obtained from Vývojový ústav traktorů a.s. of Zetor Group company was made use of.
63

Most přes Knovízský potok / Bridge over the Knovízský brook

Navrátil, Tomáš January 2016 (has links)
The subject of the diploma thesis is the design of the ghrinder bridge over the Knovízský potok brook valley. The main topic is static calculation of supporting construction of five span structure. Three studies were executed and one of them, pre-stressed girder bridge was chosen. The langht of the spans is 27 + 3 x 32 + 27 m. Static model and effect of loading are solved in software Scia Engineer. Reviews are caltulated by hand according to current standards.
64

Verspannungstechniken zur Leistungssteigerung von SOI-CMOS-Transistoren

Flachowsky, Stefan 25 October 2010 (has links)
Mit dem Erreichen der Grenzen der konventionellen MOSFET-Skalierung werden neue Techniken untersucht, um die Leistungsfähigkeit der CMOS-Technologie dem bisherigen Trend folgend weiter zu steigern. Einer dieser Ansätze ist die Verwendung mechanischer Verspannungen im Transistorkanal. Mechanische Verspannungen führen zu Kristalldeformationen und ändern die elektronische Bandstruktur von Silizium, so dass n- und p-MOSFETs mit verspannten Kanälen erhöhte Ladungsträgerbeweglichkeiten und demzufolge eine gesteigerte Leistungsfähigkeit aufweisen. Die vorliegende Arbeit beschäftigt sich mit den Auswirkungen mechanischer Verspannungen auf die elektronischen Eigenschaften planarer Silicon-On-Insulator-MOSFETs für Höchstleistungsanwendungen sowie mit deren Optimierung und technologischen Begrenzungen. Der Effekt der Verspannung auf die Bandstruktur von Silizium und die Ladungsträgerbeweglichkeit wird zunächst systematisch mit Hilfe der empirischen Pseudopotenzialmethode und der Deformationspotenzialtheorie untersucht. Verringerte Streuraten und kleinere effektive Massen als Folge der Aufspaltung der Energiebänder sowie von Bandverformungen sind der Hauptgrund für eine erhöhte Löcher- bzw. Elektronenbeweglichkeit. Die unterschiedlichen Konzepte zur Erzeugung der Verspannung werden kurz rekapituliert. Der Schwerpunkt der Untersuchungen liegt auf den verspannten Deckschichten, den Si1-xGex- bzw. Si1-yCy- Source/Drain-Gebieten, den verspannungsspeichernden Prozessen und den verspannten Substraten. Die starke Abhängigkeit dieser Verspannungstechniken von der Transistorstruktur macht die Nutzung numerischer Simulationen unabdingbar. So werden die Auswirkungen von Variationen der Transistorgeometrie sowie von Prozessparametern im Hinblick auf die Verspannung und die Drainstromänderungen der Transistoren neben den Messungen am gefertigten Transistor auch anhand numerischer Simulationen dargestellt und verglichen. Wesentliche Parameter für eine erhöhte Verspannung werden bestimmt und technologische Herausforderungen bei der Prozessintegration diskutiert. Die durchgeführten Simulationen und das erlangte Verständnis der Wirkungsweise der Verspannungstechniken ermöglichen es, das Potenzial dieser Verspannungstechniken für weitere Leistungssteigerungen in zukünftigen Technologiegenerationen abzuschätzen. Dadurch ist es möglich, die Prozessbedingungen und die Eigenschaften der fertigen Bauelemente im Hinblick auf eine gesteigerte Leistungsfähigkeit hin zu optimieren. Mit der weiteren Verkleinerung der Strukturgrößen der Bauelemente wird der zunehmende Einfluss der parasitären Source/Drain-Widerstände als Begrenzung der Effektivität der Verspannungstechniken identifiziert. Anschließend werden die Wechselwirkungen zwischen den einzelnen Verspannungstechniken hervorgehoben bzw. die gegebenenfalls auftretenden Einschränkungen angesprochen. Abschließend wird das Transportverhalten sowohl im linearen ohmschen Bereich als auch unter dem Einfluss hoher elektrischer Feldstärken analysiert und die deutlichen Unterschiede für die Leistungssteigerungen der verspannten n- und p-MOSFETs begründet. / As conventional MOSFET scaling is reaching its limits, several novel techniques are investigated to extend the CMOS roadmap. One of these techniques is the introduction of mechanical strain in the silicon transistor channel. Because strain changes the inter-atomic distances and thus the electronic band structure of silicon, ntype and p-type transistors with strained channels can show enhanced carrier mobility and performance. The purpose of this thesis is to analyze and understand the effects of strain on the electronic properties of planar silicon-on-insulator MOSFETs for high-performance applications as well as the optimization of various stress techniques and their technological limitations. First, the effect of strain on the electronic band structure of silicon and the carrier mobility is studied systematically using the empirical pseudopotential method and the deformation potential theory. Strain-induced energy band splitting and band deformations alter the electron and hole mobility through modulated effective masses and modified scattering rates. The various concepts for strain generation inside the transistor channel are reviewed. The focus of this work is on strained overlayer films, strained Si1-xGex and Si1-yCy in the source/drain regions, stress memorization techniques and strained substrates. It is shown, that strained silicon based improvements are highly sensitive to the device layout and geometry. For that reason, numerical simulations are indispensable to analyze the efficiency of the strain techniques to transfer strain into the channel. In close relation with experimental work the results from detailed simulation studies including parameter variations and material analyses are presented, as well as a thorough investigation of critical parameters to increase the strain in the transistor channel. Thus, the process conditions and the properties of the fabricated devices can be optimized with respect to higher performance. In addition, technological limitations are discussed and the potential of the different strain techniques for further performance enhancements in future technology generations is evaluated. With the continuing reduction in device dimensions the detrimental impact of the parasitic source/drain resistance on device performance is quantified and projected to be the bottleneck for strain-induced performance improvements. Next, the effects from a combination of individual strain techniques are studied and their interactions or possible restrictions are highlighted. Finally, the transport properties in the low-field transport regime as well as under high electrical fields are analyzed and the notable differences between strained n-type and p-type transistors are discussed.
65

[en] A THEORETICAL - EXPERIMENTAL STUDY OF PRE-STRESSED STAYED STEEL COLUMNS / [pt] ESTUDO TEÓRICO-EXPERIMENTAL DE COLUNAS DE AÇO ESTAIADAS E PROTENDIDAS

RICARDO RODRIGUES DE ARAUJO 29 August 2005 (has links)
[pt] Colunas protendidas de aço representam uma excelente solução estrutural em escoramentos de grandes estruturas e em colunas de estruturas espaciais de apoio a lonas tensionadas de coberturas de grandes vãos. Após um estudo extensivo do comportamento teórico através do uso do programa ANSYS onde avaliou-se a geometria estrutural mais eficiente, níveis de protensão e características dos cabos de aço, foram então definidos os diversos ensaios experimentais a serem executados em colunas com doze metros de comprimento e com tubos de 89,3 mm de diâmetro. A característica inédita deste estudo é a execução de ensaios tri-dimensionais em escala real deste tipo de coluna. Foram executadas comparações de resultados teóricos com os obtidos experimentalmente e foram feitas recomendações de análise e projeto destas estruturas. / [en] Pre-stressed steel columns represent an efficient structural solution for a great variety of temporary/permanent supports systems including large span spatial structures using pre-tensioned fabrics. The first step of the present investigation comprised a painstaking investigation of the structural behaviour of these members with the aid of finite element simulations performed with the ANSYS program. Its results indicated trends for the determination of the most efficient structural geometries, steel ties pre-stressing levels and characteristics. With these results in hand, the investigation proceeded with full-scale experimental tests executed in twelve meters pre-stressed stayed steel columns with an approximately diameter of ninety millimetres. The main contribution of the present investigation was the conception, development and execution of new tri-dimensional full-scale tests for this load bearing systems. The test results enable theoretical and numerical results to be validated against experimental evidence later to be introduced in structural design codes.
66

Obvodní oddělení Policie ČR v Kyjově / District police department of the Czech Republic in Kyjov

Šibalová, Lenka Unknown Date (has links)
The aim of this master thesis is multi-criteria assessment SBToolCZ of the building district department for Czech police in Kyjov. The building has a basement with underground garages, shooting range and technical facilities (boiler room, air conditioning room, storage, archives, cleaning room), and a ground floor with offices covered by a flat roof. The load-bearing structure of the basement is designed from watertight reinforced concrete. The ground floor has ceramic block walls. The floor and roof structure are designed from pre-stressed Spiroll. The building envelope is insulated with ETICS. The thesis also contains project documentation of building and HVAC design. The project was carried out in the AutoCad programme. Project documentation was prepared according to valid legal and technical regulations.
67

Stressed Syllables in Argentine Spanish in Queens, NYC: Lengthening and F0 Early Peak Alignment

Meiling, Giselle Gimenez 01 May 2015 (has links) (PDF)
This thesis investigates the intonation of Argentine Spanish in Queens, NYC, with the goal of verifying if the unique prosody of producing early peak alignments in the F0 of Argentine Spanish, specifically of Porteños (those from Buenos Aires), is maintained among the intense contact influences with other varieties of Spanish in the area. Previous studies have reported this early peak alignment phenomenon in the Spanish spoken in Buenos Aires, and this paper strives to see if this still occurs among Argentine Spanish speakers in New York City. The Buenos Aires speakers were compared with other native Argentine Spanish speakers in New York City who originated from provinces other than Buenos Aires (primarily from Mendoza) to verify if the dialectal varieties of Argentine Spanish had remained the same under the intense language contact situation of living in Queens. The data in the current study are from interviews recorded during the summer of 2014 in the Queens, NYC neighborhood of Elmhurst. Acoustic information obtained includes total syllable duration, F0 measurements, and F0 patterns. Additional linguistic variables included vowel type and vowel syllable position within a word. Extralinguistic variables included speaker sex, age, origin in Argentina, educational level, number of years in NYC, and number of years in Argentina. Results indicate that early peak alignment does indeed occur among Argentine speakers in Queens, NYC; however, it is interesting to note that it not only occurs in the informants from Buenos Aires as predicted, but in the informants from outside Buenos Aires as well. This suggests that the Outside Buenos Aires speakers are undergoing prosodic dialectal leveling with their pitch accent patterns and an increase in stressed syllable duration as occur naturally among the Buenos Aires speakers.
68

METHODS TO ADJUST THE PHYSICAL PROPERTIES OF LIQUID CRYSTALS AND RELATED DEVICES

ATKURI, HARI MUKUNDA 26 July 2012 (has links)
No description available.
69

Stavebně technologický projekt demolice a stavby mostu / CONSTRUCTION-TECHNOLOGY PROJECT OF BRIDGE DEMOLITION AND BRIDGE CONSTRUCTION

Hofírek, Radovan January 2018 (has links)
This diploma thesis deals with the demolition of a bridge located at the D1 motorway from Prague to Brno. The bridge no longer meets the load and width requirements of today´s standards. The thesis also deals with the construction of a new bridge, which will be expanded into D28/120 category. This expansion will allow for provisory use of the carriageways of one half of the motorway in both directions. The whole reconstruction is very time consuming that is the reason the new bridge is made of prefabricated pre-tensioned girders with a composite bridge deck. This can save time and the new bridge can be open for service in a shorter period of time.
70

Hotel / Hotel

Mikač, Jakub January 2018 (has links)
This diploma thesis solves design of the new building for temporary accommodation. The building of hotel is located in the center of village Halenkov on plot no. 103/1, which is city plan for construction of buildins for development. The building is designed as two and no cellerage. The floor plan of designed building is creating the shape of letter L. The has gabled roof with a slope of 40 degree at the part for accomodation and single-layer flat at the part for restaurant. The building is of brick construction system of Porotherm blocks based on concrete footings. The ceilings consist of reinforced concrete monolithic slab andpre-stressed concrete floor slabs. The hotel is equipped with 27 rooms for 50 guests and the restaurant is designed for 72 customers. The thesis is processed in the form of project documentation for new building, containing all the requirements according to applicable standards and regulations.

Page generated in 0.0623 seconds