• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 44
  • 14
  • 11
  • 10
  • 8
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 125
  • 18
  • 16
  • 15
  • 12
  • 11
  • 11
  • 10
  • 9
  • 9
  • 9
  • 8
  • 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.
101

DEVELOPMENT OF CEMENTITIOUS MATERIALS FOR ADHESION TYPE APPLICATIONS COMPRISING CALCIUM SULFOALUMINATE (CSA) CEMENT AND LATEX POLYMER

Brien, Joshua V 01 January 2014 (has links)
The objective of this research was to develop high performing polymer modified calcium sulfoaluminate (CSA) cement materials for use in applications requiring superior adhesion characteristics. Little information is available describing interactions of CSA cement containing minor phase tri-calcium aluminate (C3A) with commonly used admixtures. Given the scarcity of information, a basic approach for developing cementitious materials was followed. The basic approach consisted of four tasks: cement design, admixture design, polymer design and testing developed materials. The iterative, time consuming process is necessary for understanding the influence of specific constituent components on overall system behavior. Results from the cement design task suggest calcium sulfate type influences microstructural characteristics and strength development for materials based upon the experimental CSA cement. Results from the admixture design task suggest lithium carbonate and tartaric acid are effective accelerating and retarding admixtures for hydration reactions including reactants yeelimite, calcium sulfate and water. Results from the polymer design task suggest vinyl acetate / ethylene (VAE) dispersible polymer powders (DPP) are compatible with systems containing the experimental CSA cement and other commonly used admixtures. Additionally, results from the polymer design task highlight a method for specifying the ductile behavior of materials containing the experimental CSA cement as majority hydraulic binding agent. Finally, results from the testing of developed materials task suggests adhesion performance for materials containing the experimental CSA cement can be influenced by adjusting the ratio of polymer to hydraulic binding agent in material formulations. Polymer modified CSA cement mortars demonstrated bond strength resulting in substrate failure when cast over porous concrete substrates. Developed mortars demonstrated consistent bonding performance when applied to non-porous substrate materials, metal and glass. Select polymer modified mortars displayed adhesion bond performance such that the glass substrate materials fractured during pull off testing.
102

An Introduction to Modern Pricing of Interest Rate Derivatives

Nohrouzian, Hossein January 2015 (has links)
This thesis studies interest rates (even negative), interest rate derivatives and term structure of interest rates. We review the different types of interest rates and go through the evaluation of a derivative using risk-neutral and forward-neutral methods. Moreover, the construction of interest rate models (term-structure models), pricing of bonds and interest rate derivatives, using both equilibrium and no-arbitrage approaches are discussed, compared and contrasted. Further, we look at the HJM framework and the LMM model to evaluate and simulate forward curves and find the forward rates as the discount factors. Finally, the new framework (after financial crisis in 2008), under the collateral agreement (CSA) has been taken into consideration.
103

Shear Behaviour of Precast/Prestressed Hollow-Core Slabs

Celal, Mahmut Sami 12 January 2012 (has links)
Shear strength of precast/prestressed hollow-core (PHC) slabs subjected to concentrated or line loads, especially near supports, may be critical and usually is the governing criteria in the design. This study presents the second phase of a research program, undergoing at the University of Manitoba, to calibrate the shear equations in the Canadian code for predicting the shear capacity of PHC slabs. This phase includes both experimental and numerical investigations using a finite element analysis (FEA) software package. The length of bearing, void shape and size, level of prestressing and shear span-to-depth ratio were investigated. The experimental results were compared to the predictions of the Canadian, American and European codes. It was concluded that the Canadian code is unduly conservative. However, the special European code for PHC slabs resulted in better and more consistent predictions. The FEA suggested that the adequate prestressing reinforcement ratio to obtain highest shear capacity ranges between 0.7% and 1.1%.
104

Aktivace svalů břišní stěny a svalů zad při cvičení s trakčním a kompresním zatížením / Activation of abdominal wall and back muscles during exercise with traction and compression loads

Jordáková, Adela January 2018 (has links)
We used RUSI (rehabilitative ultrasound imaging) for measurement of abdominal and back muscle in different loading modes. Methods: We used diagnostic ultrasonography imaging for taking linear measurement of trunk muscles. We measured anterioposterior (AP) dimensions of lateral abdominal wall muscles- m. OE, m.OI, m.TrA and cross-section area (CSA) of lumbar m. multifidus. We compared two groups of sports-floorball players and sportsman using climbing and hanging (climbers, aerialists). We measured positions with compressive force (kneeling on all four with lifted knees) and with traction load (hang with upper limbs with flexion of lower limbs-with leg support and without). Study is made on 50 volunteers. Results: The pattern of thickness of abdominal muscles is same in all positions in both groups. The lowest is always AP thickness of m. TrA, wider is m. OE and the widest always m. OI. The resting thickness are in both groups almost in all cases the lowest. AP thickness in m. TrA in floorball players is only exception, there is lowest in hang without legs support. In all other case sis resting position always lowest. For m. OE are results same for both climbers and floorball players-the lowest thickness is in hang with legs support (floorball players 0,84 cm, climbers 0,87), greater activationis...
105

Characterisation of inorganic materials using solid-state NMR spectroscopy

Sneddon, Scott January 2016 (has links)
This thesis uses solid-state nuclear magnetic resonance (NMR) spectroscopy and density functional theory (DFT) calculations to study local structure and disorder in inorganic materials. Initial work concerns microporous aluminophosphate frameworks, where the importance of semi-empirical dispersion correction (SEDC) schemes in structural optimisation using DFT is evaluated. These schemes provide structures in better agreement with experimental diffraction measurements, but very similar NMR parameters are obtained for any structures where the atomic coordinates are optimised, owing to the similarity of the local geometry. The ³¹P anisotropic shielding parameters (Ω and κ) are then measured using amplified PASS experiments, but there appears to be no strong correlation of these with any single geometrical parameter. In subsequent work, a range of zeolitic imidazolate frameworks (ZIFs) are investigated. Assignment of ¹³C and ¹⁵N NMR spectra, and measurement of the anisotropic NMR parameters, enabled the number and type of linkers present to be determined. For ¹⁵N, differences in Ω may provide information on the framework topology. While ⁶⁷Zn measurements are experimentally challenging and periodic DFT calculations are currently unreliable, calculations on small model clusters provide good agreement with experiment and indicate that ⁶⁷Zn NMR spectra are sensitive to the local structure. Finally, a series of pyrochlore-based ceramics (Y₂Hf₂₋ₓSnₓO₇) is investigated. A phase transformation from pyrochlore to a disordered defect fluorite phase is predicted, but ⁸⁹Y and ¹¹⁹Sn NMR reveal that rather than a solid solution, a significant two-phase region is present, with a maximum of ~12% Hf incorporated into the pyrochlore phase. The use of ¹⁷O NMR to provide insight into the local structure and disorder in these materials is also investigated. Once the different T₁ relaxation and nutation behaviour is considered it is shown that quantitative ¹⁷O enrichment of Y₂Sn₂O₇ is possible, and that ¹⁷O does offer a promising future tool for study.
106

Sonografické hodnocení n. Ischiadicus u jedinců s radikulární symptomatikou S1 / Sonographic evaluation of the ischial nerve in individuals with radicular symptoms S1

Kurková, Simona January 2019 (has links)
Bibliographical record: KURKOVÁ, Simona. Sonographic evaluation of sciatic nerve in individuals with radicular symptoms S1, Charles University, 2nd Faculty of Medicine, Department of Rehabilitation and Sports Medicine, 2019, p. 99, Thesis Supervisor: Mgr. Stanislav Machač Ph.D. Abstract The thesis deals with radicular symptomatics S1 and sonographic imaging and evaluation of sciatic nerve in individuals with unilateral radicular manifestation. The theoretical part describes anatomy and biomechanics of nerve structures, radicular syndrome and its clinical image, diagnostics and treatment. The theory also includes the less known extraspinal causes manifesting themselves as radicular syndrome, the effects of which may be equally important in differential diagnosis. It describes classical and new possibilities of nerve imaging with emphasis on sonography and approach of new procedures such as MRI tractography. In the practical part, the aim of the thesis is to evaluate morphological changes of sciatic nerve in patients with unilateral symptomatic S1 by sonographic imaging of the nerve during its course, from the subgluteal groove to the popliteal groove. It also examines the relationship between the pathophysiology and symptomatology of these patients, comparing whether changes in nerve size correlate with...
107

Využití vnitřní kompozitní výztuže při návrhu odolných betonových konstrukcí / The use of internal composite reinforcement in the design of durable concrete structures

Koriťáková, Martina January 2022 (has links)
The diploma thesis deals with processing of determining the shear strength of concrete structures reinforced with composite reinforcement, subjected to shear force, according to five different design approaches. The theoretical part of the thesis is closely related to the project FW01010520 - "Development of bent composite reinforcement for environmentally exposed concrete constructions", which is realized at the Institut of Concrete and Masonry Structures, Faculty of Civil Engineering, Brno University of Technology. The project deals with the shear strength of concrete beams reinforced with steel and composite reinforcement in various combinations. Then the load-bearing results gained within the project are compared with the values obtained by calculations according to the solved design approaches and computer software Atena Science. The second part of the diploma thesis deals with the static design and assessment of the cell structure. The cell is designed as a room inside of the medical building, where is placed device of magnetic resonance which is the reason why the cell is reinforced with non-magnetic composite reinforcement.
108

The Importance of a Social Movement to Reduce Childhood Sexual Abuse & Recommendations for Implementation of a Movement

Vereschagin, Brittany 29 June 2022 (has links)
No description available.
109

Using the Unified Theory of Acceptance and Use Technology to Determine Factors that affect the Acceptance and Use of Social Media to Advertise and Promote Agriproducts in Farmer' Communities in North Mississippi

Moreno-Ortiz, Carlos Alberto 14 December 2018 (has links)
The present empirical study examined factors that affect the acceptance and use of social media platforms by farmers and vendors in farmers’ communities in North Mississippi for marketing their small farm businesses. Based on the Unified Theory of Acceptance and Use of Technology (UTAUT), structural equations modeling was used to examine several relationships: (1) the influence of performance expectancy (PE) on behavioral intention (BI) to use social media; (2) the influence of effort expectancy (EE) on BI; (3) the influence of social influence (SI) on BI; (4) the influence of facilitating conditions (FC) on actual use (USE) of social media; (5) the moderating influence of gender on the PE–BI, EE–BI, and SI-BI relationships; (6) the moderating influence of age on the PE–BI, EE–BI, SI-BI, and FC–USE relationships; and (7) the moderating influence of experience using social media on the EE–BI, SI-BI, and FC–USE relationships. Results from 169 respondents who completed questionnaires indicated that PE, EE, SI, and FC (key constructs) did predict farmers and vendors’ BI to use social media and actual USE of social media for marketing their small farm businesses and agriproducts. Respondents’ characteristics (e.g., age, gender, social media experience) did moderate some of these relationships in different ways. Thus, the present study provided additional empirical support for UTAUT. Additionally, responses to questions that assessed constructs in UTAUT suggest that respondents are open to social media as a marketing tool for their small farm businesses. Other results indicated that farmers and vendors prefer to market their products through farmers markets and community supported agriculture groups as compared to retail outlets and noted barriers present in retail marketing channels. This study provides information that will be beneficial for the development of educational programs and contributes to the literature on the factors affecting farmers’ intention to use social media to promote agriproducts to connect new markets.
110

Investigating Neck Muscle Size and Strength with Concussion Risk in Soccer Players

Barry, Kimberly E. 22 September 2014 (has links)
No description available.

Page generated in 0.0271 seconds