Validation of Nonlinear Hydrodynamic Load Models for a Monopile in Long-Crested Waves

This Master Thesis studies an offshore wind turbine supported by a monopile structure. Model tests for a fully flexible monopile were carried out in the Ocean Basin facility at SINTEF Ocean in August 2017, through the NOWITECH project. This thesis examines selected results from the experiments and introduces numerical simulations for comparison to the experimental results. For the numerical simulations the software SIMA RIFLEX, a finite element solver for static and dynamic analysis of slender marine structures, is utilized. The main focus has been put on validation of hydrodynamic load models, both linear and nonlinear, that can describe the response from the experiments, both on a statistical level and for single events. A literature review regarding nonlinear hydrodynamic load models and ringing responses is performed. The literature review focuses on observations of ringing responses and the mechanisms that lead to ringing. A beam element model was built in SIMA and presented by the Supervisor as a starting point to this thesis. The model was calibrated based on available decay tests from the experiments to have the same system damping ratio (0.47%) and first mode eigenfrequency (1.42 rad/s) as the experimental model. The damping ratio was estimated as 0.47%, which is considered to be relatively low compared to similar monopile supported offshore wind turbines in full scale, where damping ratios have been found up to 2.8%. An eigenvalue analysis was also conducted to confirm the eigenfrequencies found from the decay tests. The eigenvalue analysis also conveniently provided the modal shapes of the three first bending modes. Regular wave tests were treated to establish the RAOs for first, second and third order. The first-order RAOs displayed a reasonable behaviour with good agreement between the simulated and experimental. The second order RAO also showed good agreement between the simulated and experimental results, except for one wave period, T = 9 s, where a strong over-prediction was made in the simulations. For the simulations of the regular wave tests, Morison's equation with linear kinematics was used together with the MacCamy-Fuchs correction for diffraction. However, only linear diffraction is accounted for by this method. The over-prediction may be a result of not taking second order diffraction effects into account in the simulations. The third order RAOs were of an order of magnitude lower than the first and second order RAOs. Thus, some uncertainty due to accuracy of measurements were connected to the third order RAOs. A repeatability analysis for the experiments was performed for nine repeated irregular wave tests. The repeatability analysis revealed through the coefficient of variation that the random error connected to global maxima for the moment response was below 10%, indicating quite good repeatability. A considerably larger random error, far above 10%, was connected to the repetition of the magnitude of single event maxima. The coefficient of variation was also considered for the maximum wave amplitude at two different wave probes. This revealed that both global maxima and single event maxima were repeated quite well, with coefficient of variation below 10%. A parameter study on the damping was initiated as the damping in the system, estimated from the decay tests was very low. Realistic damping ratios were found in the literature and considered. It is found that the originally estimated damping ratio is likely to not be representative of the system damping when the structure is subjected to waves. This is suggested based on the simulations with linear theory overestimating the response from the experimental tests, which is contradictory to what is found in the literature when considering extreme sea states. If a more realistic damping ratio of 1.1% is accepted as the damping ratio for the structure, it is found that linear wave kinematics with Wheeler stretching is the most appropriate method for describing the energy in the response from the experimental tests. Ringing responses were identified in the experimental tests and were in agreement with how the phenomenon is described in the literature. It is found in the experiments that ringing responses are initiated by large, steep wave events. The ringing events characteristically have a large amplification from the steady state response and decays with the eigenfrequency for some periods. Clear ringing events were not found in the simulations. More likely than not, higher order than second order theory must be considered to properly describe the ringing phenomenon

Regulation of small GTPase function during phagocytosis

Phagocytosis is the process whereby cells bind and engulf particulate materials via the localised remodelling of the actin cytoskeleton. Small GTPases of the Rho family have been widely implicated in co-ordinating actin dynamics during diverse cellular processes, including phagocytosis, yet the signalling mechanisms controlling their recruitment and activation remain unclear. This thesis investigates the signalling pathways involved in regulating small GTPase function during phagocytosis via two distinct receptors, the FcγR, which is known to require Cdc42 and Rac and the complement receptor 3 (CR3, αMβ2, CD11b/CD18), which is known to couple to Rho. Data is presented showing that in response to FcγR ligation, Cdc42 and Rac are activated. Moreover, the guanine nucleotide exchange factor, Vav translocates to nascent phagosomes and promotes GTP-loading on Rac, but not Cdc42. The Vav induced Rac activation proceeds independently of Cdc42 function suggesting distinct roles for each GTPase during engulfment. Moreover, inhibition of Vav exchange activity or of Cdc42 activity does not prevent Rac recruitment to sites of particle attachment. This suggests that Rac is recruited to Fcγ membrane receptors in its inactive, GDP-bound state and that Vav regulates phagocytosis through subsequent catalysis of GDP/GTP exchange on Rac. In contrast, phagocytosis via the integrin receptor CR3 (αMβ2) proceeds via a two-step mechanism involving inside-out signalling to activate the receptor and ligand directed engulfment. Evidence supporting independent roles for the cytoplasmic tails of CR3 in regulating these activities is presented, with the β2 (CD18) tail directing receptor activation and the αM (CD11b) tail promoting the activation of Rho, necessary for engulfment

Single and Dual Growth Factor Delivery from Poly-E-caprolactone Scaffolds for Pre-Fabricated Bone Flap Engineering.

Autografts are utilized to reconstruct large craniofacial bone defects; however, they result in donor site morbidity and defect geometry mismatch. Pre-fabricating a bone flap overcomes these drawbacks by integrating a patient specific scaffold with biologics, implanting it in the latissimus dorsi for a period of time and then transplanting it to the defect site as a partially remodeled construct. Polycaprolactone (PCL) is a biocompatible polymer that has mechanical properties suitable for bone tissue engineering. It must be integrated with biologics, however, to stimulate bone formation. The purpose of this work was to investigate bone regeneration using PCL and dual protein delivery. Bone morphogenetic protein-2 (BMP2) was adsorbed or conjugated onto a PCL scaffold in a clinically applicable setting (1 hour exposure at room temperature). Adsorbed BMP2 had a small burst release and was bioactive as indicated by C2C12 alkaline phosphatase expression. Interestingly, conjugated BMP2 had a sustained release but was not bioactive. When implanted subcutaneously, adsorbed BMP2 had increased bone volume (BV), elastic modulus, and ingrowth when compared to conjugation. Next, a collagen sponge was fabricated inside of a BMP2-adsorbed PCL scaffold to deliver vascular endothelial growth factor (VEGF). In addition, a modular PCL scaffold was developed in which the inner and outer modular portions were adsorbed with BMP2 and VEGF, respectively. In both systems, the VEGF was bioactive as indicated by increased endothelial cell proliferation. Dual delivery of BMP2+VEGF significantly increased BV from 4 to 8 weeks in an ectopic location, whereas, BMP2 alone did not. Finally, erythropoietin (EPO) and BMP2 were delivered from the outer and inner portions of the modular scaffold, respectively. The adsorbed EPO was bioactive as indicated by increased endothelial cell proliferation. At 4 weeks, dual EPO+BMP2 delivery significantly increased BV and ingrowth when compared to BMP2 alone. In conclusion, adsorbing BMP2 onto PCL may be optimal for clinical use. Delivering VEGF with BMP2 increases the bone regeneration rate from 4 to 8 weeks, and delivering EPO with BMP2 increases the BV at 4 weeks when compared to BMP2 alone, making multiple biologics delivery a promising method to increase the regenerated bone for pre-fabricated flaps.PhDBiomedical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111451/1/jankip_1.pd

Farmakokinetika ceftriaksona u teladi

The pharmacokinetics of ceftriaxone was determined after a single intravenous and intramuscular administration at the dose rate of 10 mg/kg in crossbred cow calves. The drug concentration in plasma was quantified through High Performance Liquid Chromatography with UV detection. Following intravenous administration the drug was rapidly distributed (t1/2α: 0.13 ± 0.01 h; Vd(area); 0.44 ± 0.07 L/kg) and eliminated (t1/2β: 1.58 ± 0.06 h) from the body with a clearance rate of 3.15 ± 0.41 mL/min/kg. Following intramuscular administration, the peak plasma drug concentration (Cmax) was 15.34 ± 2.39 μg/mL at 0.25 hours (Tmax) suggesting very rapid absorption. The drug was extensively distributed (Vd(area): 1.16 ± 0.15 L/kg) and slowly eliminated (t1/2β: 5.02 ± 0.51 hours; Cl(B): 2.71 ± 0.29 mL/min/kg) following intramuscular administration. The absolute bioavailability of ceftriaxone was 47.0 ± 5.0% following intramuscular injection. However, it can be used at a dosage of 10 mg/kg intramuscularly, repeated at twelve-hourly intervals, for the treatment of susceptible bacteria infections in calves.Farmakokinetika ceftriaksona određivana je u križane teladi nakon njegove jednokratne intravenske i intramuskularne primjene u dozi od 10 mg/kg. Koncentracija lijeka u plazmi određivana je tekućinskom kromatografifi jom visokog učinka s UV zrakama. Raspodjela lijeka bila je brza nakon intravenske primjene (t1/2α: 0,13 ± 0,01 h; Vd(area): 0,44 ± 0,07 L/kg), a izlučivanje (t1/2β: 1,58 ± 0,06 h) iz tijela s klirensom od 3,15 ± 0,41 mL/min/kg. Nakon intramuskularne primjene vršna koncentracija u plazmi iznosila je (Cmax) 15,34 ± 2,39 μg/mL tijekom 0,25 sati (Tmax) što upućuje na vrlo brzu apsorpciju. Raspodjela lijeka bila je izrazito dobra (Vd(area) 1,16 ± 0,15 L/kg), a izlučivanje sporo (t1/2β: 5,02 ± 0,51 sati; Cl(B): 2,71 ± 0,29 mL/min/kg) nakon intramuskularne primjene. Apsolutna biološka raspoloživost nakon intramuskularne primjene ceftriaksona iznosila je 47,0 ± 5,0%. Međutim, on se može rabiti u dozi od 10 mg/kg i.m. te ponavljati u razmacima od 12 sati radi liječenja bakterijskih zaraza u teladi

(R1966) Semi Analytical Approach to Study Mathematical Model of Atmospheric Internal Waves Phenomenon

This research aims to study atmospheric internal waves which occur within the fluid rather than on the surface. The mathematical model of the shallow fluid hypothesis leads to a coupled nonlinear system of partial differential equations. In the shallow flow model, the primary assumption is that vertical size is smaller than horizontal size. This model can precisely replicate atmospheric internal waves because waves are dispersed over a vast horizontal area. A semi-analytical approach, namely modified differential transform, is applied successfully in this research. The proposed method obtains an approximate analytical solution in the form of convergent series without any linearization, perturbation, or calculation of unneeded terms, which is a significant advantage over other existing methods. To test the effectiveness and accuracy of the proposed method, obtained results are compared with Elzaki Adomain Decomposition Method, Modified Differential Transform Method, and Homotopy Analysis Method

A Survey: Privacy Preserving Using Obfuscated Attribute In e-Health Cloud

Cloud computing now a day’s provides numerous number of benefits to their users. As the Cloud infrastructure is not directly under control of user its seems to be difficult for user to have a better security. Other side as the number of user grow even it become more difficult to manage a data such a way that user needs for any data are satisfied efficiently. There are lots of chances to misuse the data of user. So, here Cloud providers need to balance this two fundamental of Privacy handling and efficient analysis of data together is become very important. When we talk about the health records of patient or medical firm and available on remote machine issue of privacy of record provided by the anonymization fundamental. Here various researcher provided a technique T- Closeness to achieve this goal. It also important to provide the security of stored data using obfuscation mechanism . Some time full obfuscation of file consume more time so many researcher provided scheme of attribute based obfuscation which lessen the burden of Cloud server by providing adequate security and also help to execute user query faster. In this paper we aim to provide survey on various fundamental given by the different researcher

A Novel Architecture for Privacy Preserving Using obfuscated Attribute In e-Health Cloud

Cloud computing now a days provides numerous number of benefits to their users. As the Cloud infrastructure is not directly under control of user its seems to be difficult for user to have a better security. Other side as the number of user grow even it become more difficult to manage a data such a way that user needs for any data are satisfied efficiently. There are lots of chances to misuse the data of user. So, here Cloud providers need to balance this two fundamental of Privacy handling and efficient analysis of data together is become very important In this research we aim is to provide the solution of both of this issue using a novel techniques. When we talk about the health records of patient or medical firm and available on remote machine issue of privacy of record provided by the anonymization fundamental. Here we provided a technique T- Closeness to achieve this goal. We also aim is to provide the security of stored data using obfuscation mechanism. Some time full obfuscation of file consume more time so here we provided scheme of attribute based obfuscation which lessen the burden of Cloud server by providing adequate security and also help to execute user query faster. We also aim in this research to reduce the burden of the Cloud by proposing third party based approach.So, together we tried to achieve better throughput securely by increase the trust of user toward Cloud

Evaluation of Stability of Complexes of Inner Transition Metal Ions with 2-Oxo-1-pyrrolidine Acetamide and Role of Systematic Errors

BEST FIT models were used to study the complexation of inner transition metal ions like Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Dy(III) and Th(IV) with 2-oxo-1-pyrrolidine acetamide at 30 °C in 10%, 20, 30, 40, 50% and 60% v/v dioxane-water mixture at 0.2 M ionic strength. Irving Rossotti titration method was used to get titration data. Calculations were carried out with PKAS and BEST Fortran IV computer programs. The expected species like L, LH+, ML, ML2 and ML(OH)3, were obtained with SPEPLOT. Stability of complexes has increased with increasing the dioxane content. The observed change in stability can be explained on the basis of electrostatic effects, non electrostatic effects, solvating power of solvent mixture, interaction between ions and interaction of ions with solvents. Effect of systematic errors like effect of dissolved carbon dioxide, concentration of alkali, concentration of acid, concentration of ligand and concentration of metal have also been explained here