• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 144
  • 85
  • 40
  • 25
  • 21
  • 15
  • 13
  • 11
  • 9
  • 5
  • 4
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 425
  • 150
  • 128
  • 57
  • 53
  • 44
  • 44
  • 43
  • 42
  • 41
  • 41
  • 40
  • 39
  • 39
  • 35
  • 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.
401

Gender Differences in High Sensitivity C - Reactive Protein and Self-Reported Muscle Strengthening Activity Among U.S. Adults

Richardson, Michael R 01 January 2014 (has links)
Objectives: We sought to examine the gender differences between C - reactive protein (CRP) and muscle strengthening activity (MSA) in U.S. adults (≥20 years of age) Background: Elevated levels of CRP have been shown to be associated with an increase in risk of cardiovascular disease (CVD). Studies analyzing the relationship between physical activity (PA) and CRP by gender have produced mixed results. Methods: The sample (n=9,135) included participants in the 1999-2004 National Health and Nutrition Examination Survey (NHANES). Three categories of reported MSA participation were created: no MSA (referent group), some MSA (≥1 to/wk), and meeting the 2008 Department of Health and Human Services (DHHS) recommendation (>2 d/wk). The dependent variable was elevated CRP (>3 to 10 mg/L). Results: Gender stratified analysis revealed significantly lower odds of having elevated CRP for women reporting some MSA (OR 0.61; 95% CI 0.45-0.83, P=0.0023), or volumes of MSA meeting the DHHS recommendation (OR 0.66; 95% CI 0.54-0.82, P=0.0004). Significantly lower odds of men having elevated CRP was observed in those reporting MSA volumes meeting the recommendation (OR 0.73; 95% CI 0.61-0.88, P=0.0011). Following adjustment for waist circumference (WC) these odds remained significant in men but not women. Conclusions: Women reporting any MSA were found to have lower odds of having elevated CRP when compared to those reporting no MSA prior to adjustment for WC. Significantly lower odds in men were only observed in those meeting the recommendation. These results suggest that WC may mediate the associations between MSA and CRP and this relationship may be stronger in women.
402

SFB 528: Textile Bewehrungen zur Bautechnischen Verstärkung und Instandsetzung: Arbeits- und Ergebnisbericht für die Periode II/1999 - I/2002

Curbach, Manfred 04 September 2005 (has links)
Durch die beanspruchungsgerechte Anordnung von Fasermaterialien wie Glas oder Carbon mit hervorragenden Trageigenschaften entstehen technische Textilien, die in eine Betonmatrix eingebracht werden können, so daß ein neuer, innovativer Verbundwerkstoff entsteht, der sowohl bei der Herstellung neuer Betonbauteile verwendet werden kann als auch für den Einsatz in der Instandsetzung und Verstärkung bestehender Bauwerke geeignet ist. Da die verwendeten Materialien im Gegensatz zum Stahl nicht korrosionsempfindlich sind und gleichzeitig hohe Festigkeiten aufweisen, können Verstärkungen aus textilbewehrtem Beton mit sehr geringen Abmessungen ausgeführt werden. Bei Holzkonstruktionen können textile Verstärkungen die durch die Anisotropie bedingten Festigkeits- und Steifigkeitsunterschiede kompensieren und die Dauerhaftigkeit erhöhen. Bei Verzicht auf Knotenbleche aus Stahl und durch Applikation von textilen Strukturen können beachtliche Steigerungen der Tragfähigkeit und der Duktilität von Verbindungen erreicht werden. In den fünf Projektbereichen werden in theoretischen und experimentellen Untersuchungen die Grundlagen für die Werkstoffe, die mechanische Beschreibung, die konstruktive Durchbildung und die Bemessung, die technologische Aufbringung, bautechnische Umsetzung und die Langzeiteigenschaften und damit für die Sicherheit und die Lebensdauer bei der Verwendung textiler Bewehrungen für die Instandsetzung und Verstärkung geschaffen. / The stress-oriented arrangement of fibre materials, such as glass or carbon, which have an excellent load-bearing capacity, leads to technical textiles that may be incorporated into a concrete matrix. So a new, innovative composite material is produced, which can be used for the production of new concrete members and also for the restoration and strengthening of existing structures. As the materials used are noncorrosive compared to steel and as they show great strength at the same time, textile-reinforced concrete can be used for strengthening tasks of small dimensions. With regard to timber structures, textile reinforcement can compensate the strength and stiffness differences caused by anisotropy and can increase durability. If textile structures are used instead of steel gussets this may lead to a considerable increase in the ultimate strength and the ductility of joints. The five fields of the project are designed that theoretical and experimental investigations are carried out to provide the fundamentals of the materials. Additionally information will be obtained about the mechanical description, the detailing and the dimensioning, the techniques of applying, the realisation on the site and the long-term behaviour. All leading to a safety concept and also a service life concept for the use of textile reinforcements for restoration and strengthening.
403

Zesílení železobetonové konstrukce pro ocelovou nástavbu / The strengthening of the reinforced concrete structure for the steel superstructure

Tůma, Pavel January 2018 (has links)
This diploma thesis analyze reinforced concrete construction, which is loaded by new steel superstructure with brick cladding. The necessary strengthening of construction is solved by using carbon fibre reinforced polymer plates. Software RFEM 5 is used for calculation of internal forces. All checks are made in Excel.
404

Novostavba základní školy v Bobrové, stavebně technologický projekt / Project

Kudiovský, Filip January 2018 (has links)
The diploma thesis deals with the construction project of the new building of the primary school in Bobrová. The main goal of the thesis is to propose a suitable implementation procedure in relation to the specific place of the site. The thesis deals with the time schedule of the main object, itemized budget, major building machines and mechanisms, project of site equipment, study of the construction realization, material resources plan, technical report, time schedule and financial plan of the main object and also with the situation of the construction. It focuses in detail on the stage of earthworks, including the reinforcement of the walls of the building pit using soil nailing. For this stage a technological regulation and a control and test plan have been developed.
405

High Temperature Deformation Mechanisms / High Temperature Deformation Mechanisms

Heczko, Milan January 2018 (has links)
Dvě pokročilé vysoce legované austenitické oceli s Fe-Ni-Cr matricí byly studovány za podmínek nízkocyklové únavy jak za pokojové tak vysoké teploty. Široká škála experimentálních a charakterizačních nástrojů byla použita ke studiu vzájemně souvisejících aspektů zahrnujících chemické složení slitin, mikrostrukturu, deformační mechanismy a celkovou odezvu materiálů na externě působící zatížení. Klíčové mechanismy a faktory definující mechanické vlastnosti a výkonnost v reálném provozu byly analyzovány a diskutovány v souvislosti s materiálovým designem. • Standardní únavové experimenty byly provedeny za pokojové teploty a teploty 700°C. Byly získány křivky cyklického zpevnění/změkčení, cyklické deformační křivky, Coffin-Manson a Wöhlerovy křivky. • Ke studiu změn mikrostrukturního stavu slitin v důsledku cyklického zatěžování za pokojové a zvýšené teploty byla použita široká škála technik charakterizace pomocí elektronové mikroskopie. • Únavové chování, pevnost a cyklická plastická odezva studovaných materiálů byla vysvětlena v souvislosti s mikrostrukturními změnami a mikrostrukturními aspekty deformačních mechanismů jak za pokojové tak za zvýšených teplot. • Bylo zjištěno, že Sanicro 25 vykazuje nejvyšší pevnostní charakteristiky ze všech materiálů stejné třídy. Výjimečné vlastnosti této slitiny jsou spojeny s populacemi dvou typů nanočástic, koherentními precipitáty bohatými na měď a nanočásticemi typu MX s charakteristikou disperzoidu. Tyto nanočástice mají klíčový vliv na pevnost a celkovou cyklickou odezvu. V důsledku interakcí s precipitáty způsobujících zachytávání je pohyb dislokací v Sanicro 25 významně zpomalen, což vede k potlačení normálních procesů zotavení obvykle vedoucích ke změně uspořádání dislokační struktury tak, aby byla celková vnitřní energie systému co nejnižší. Takové uspořádání je tvořeno například dislokačními buňkami. Jelikož jsou procesy zotavení potlačeny, dislokační struktura za vysokých teplot je charakteristická homogenní distribucí dislokací o vysoké hustotě s velkou mírou vzájemných interakcí. V kombinaci s dalšími mechanismy zpevnění jako jsou precipitáty a substituční prvky v tuhém roztoku, tyto deformační mechanismy vedou k významnému zvýšení cyklické pevnosti za vysokých teplot.
406

Studie chování železobetonových sloupů zesílených ovinutím FRP tkaninou / Behaviour of reinforced concrete columns confined with FRP wrap

Niesner, Jakub January 2020 (has links)
Strengthening of reinforced columns confining by modern composite materials is effective method, allows quickly realized strengthening, without increase dimension of strengthening columns. Just like using reinforcing bars, is the mainly assumption for this method the multi-axis state tension and deducing confining pressure, which will increase strength of concrete. Improved of properties of confining concrete can be determined by using relationships, but there are considerably differences. This diploma theses, dealing with strengthening of circular reinforced columns confinement by external FRP fabric, compared approaches to design of reinforced concrete by confining and using the results of an analytical and numerical study to describe problem of confining concrete and compare factors influencing the final properties of the wrapped concrete.
407

Řešení statického zajištění přístavby stávajícího objektu / Structural strengthening of the outbuilding of existing construction

Pelouch, Adam January 2021 (has links)
Diploma thesis is focused on structural assessment and strengthening of the reinforced concrete flor slab disturbed by excessive deflection. Thesis included assesment of the existing construction and design method of strengthening of the floor structure with system using prestressing strands without bond.
408

Oprava a zesílení železobetonové stropní konstrukce / Reconstruction and strengthening of reinforced concrete ceiling construction

Klimeš, Petr January 2015 (has links)
The final thesis deals with strengthening of cast-in-place concrete ceiling in existing construction for couple of escalators. New prestressed beam, columns in new positions and strengthened girder with unbonded strands are building in this adjustments. Every member, including the existing construction, is verified for ultimate and serviceability limit state. Prestressed members are alternatively designed with bonded strands and these variants are comparison in terms of utilization and calculation.
409

Rekonstrukce mostu u obce Holýšov / Reconstruction of the road bridge near the village Holýšov

Svoboda, Adam January 2016 (has links)
The thesis deals with design of strengthening of existing bridge structure near the village Holýšov using modern method of additional presstresing. The bridge over the river of Radbuza is h-shaped beam bridge, which was built in 1924. In the present state its load capacity is under the limits for bridges situated on first-class roads. Original documentation of the bridge does not exist, the main source of information about construction details is the diagnostics research. The method of reinforcement by post-tensioning by cables in substituted cable ducts is highly efective in terms of the incerease the load capacity of existing bridge structure. The design of strengthening and the final load capacity was verified by static calculation.
410

Zesílení ŽB oblouku pomocí kompozitní výztuže / Reinforced concrete load-bearing construction

Tmej, Patrik January 2016 (has links)
The aim of the thesis is the strengthening and resistance of concrete construction. At the beginning is described composite reinforcement and their specific properties. The thesis specifically follows behavior concrete vault and the effects of load. Resistance vault is calculated by S&T model – strut and tie. Finally, the thesis contain strengthening construction by composite reinforcement. Strengthening is considered by two ways - strengthening by cohesive reinforcement and strengthening by incoherent reinforcement (wrapping).

Page generated in 0.0883 seconds