Dissertations / Theses: 'NOX burner'

1

Fiskum, Andreas. "Calculation of NOx Formation in a Swirl Burner." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-12869.

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This thesis embraces simulations of NOx emissions from a partially premixed 20 kW swirl burner. The simulations were carried out in the commercial computational fluid dynamics software FLUENT. The concept of partial premixing air and fuel before adding additional air for complete combustion has proven promising with a view on the NOx emissions. However, little research has been done on reach premixing of fuel and air and therefore further investigation of this topic is of interest. In most experiments in the literature methane is used as fuel, but due to problems with stability and blow off in the 20 kW swirl burner propane were chosen as fuel.Simulations of eight different air-fuel ratios have been performed, ranging from diffusion flame to a mass based air-fuel ratio of four. The results from these simulations proved satisfactory when comparing with previous experimental and simulated work, except from the calculations of the exact NOx concentration. This difference in the concentration was one the other hand expected since the power of FLUENT and similar software is to predict variation trends and not the exact value itself.The simulations showed that the NOx concentration increased with increasing premixing, reaching a local peak at an air-fuel ratio of two. After this a local minimum in the NOx concentration was observed before a strong increase when further raising the air-fuel ratio. This is the same trends that are observed in the literature when using methane as fuel, but for propane there is no global reduction in the NOx emissions when applying premixing. This increase in the NOx emission was found to be due to an expansion of the high temperature flame zone with increasing premixing, which benefits the thermal NOx formation mechanism. The NOx reducing effect of swirl generation observed to decrease when the air-fuel ratio was increased. For subsequent experimental work it is recommended to perform a high amount of experiments at different air-fuel ratios, especially in the ratio range where the NOx concentrations starts to fluctuate.

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2

O'Nions, Phillip. "Low NOx combustion utilising a Coanda ejector burner." Thesis, University of Sheffield, 1998. http://etheses.whiterose.ac.uk/14674/.

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Current and future pollutant enussion legislation calls for decreased NOx emissions from combustion systems. A review of techniques used for NOx abatement led to the choice of combustor redesign to be the most cost effective method available. This led to the design, construction and development of a combustion system that utilised a Coanda ejector to generate recirculation of the exiting high temperature combustion products to mix with the air supply. Cooling of the burner was integrated into the design through the use of the air and fuel supplies. Computational fluid dynamics was used to model and aid development of the design. The model was used to predict NOx and CO emissions and the fuel-air mixing pattern. This, along with an analysis of experimental results and observations led to an understanding of the burner operation with respect to pollutant emissions and stability. NOx emissions from the Coanda burner were found to be lowest when using a 0.2 mm Coanda gap width, resulting in 16 ppm NOx being emitted at an air to fuel ratio of 1.5. However, the use ofa 0.2 mm Coanda gap width required an air supply pressure of up to 4 bar. The use of a 0.5 mm Coanda gap width enabled burner operation at lower air supply pressures. The resulting NOx emissions were measured as 23 ppm at an air to fuel ratio of 1.I, with a corresponding exit gas temperature of 2200 K. Flue gas recirculation quantity, flame stability, flame stabiliser shape and operational limits proved to be inter-linked in the reduction of NOx emissions. It was found that fuel-air mixing was controlled by the entrainment properties of the Coanda ejector and the flame stabiliser. The average oxygen concentration entering the combustion chamber when using a 0.2 mm and 0.5 mm Coanda gap width was 13.7 % and 16.6 %, respectively. Due to the position of the fuel injector, a fuel rich region formed behind the flame stabiliser. With a suitable flame stabiliser geometry and the use of 'fingers', low NOx combustion and flame stability was achieved near stoichiometric conditions. It was shown that the design of the burner enabled very low pollutant emissions near stoichiometric conditions, resulting in high exit gas temperatures. Conceivable applications of this type of burner could lie in small and intermediate furnaces where low NOx emissions are required. Additionally, very high temperature applications, such as glass furnaces could benefit in both cost and pollutant emissions from such a burner.

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3

Mohammadi, Peyman. "DLE burner water rig simulations." Thesis, Mälardalen University, Department of Computer Science and Electronics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-626.

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In today’s industrial world, there are high demands on the environmental aspects.

Siemens Industrial Turbomachinery AB (SIT AB) is a company that is keen about the environment, and therefore spends a lot of effort in developing combustion processes in order to reduce NOx (nitrogen oxides) emissions on their engine products. They are also researching in optional fuels, which are more environment-friendly.

In order to provide lower emissions the SIT designed a water rig to study the flow dynamics in a DLE (Dry Low Emission) burner.

An analyze program (GUI horizontal) was developed with new functions and the existing functions were improved. The program’s function was to evaluate different experimental tests of the flow dynamics in the 3rd generation DLE burners, of the SGT-800 gas turbine engine.

The aim was to ensure repeatability to enhance reliability, of the experimental test results for further comparison, for upcoming projects concerning future DLE burners.

When repeatability was achieved, implementations of different geometrical modifications were performed in the 3rd generation DLE burner.

The reason of the geometrical alterations was to look over if better fuel air mixture could be obtained and accordingly (thus) to reduce hotspots in the burner and in that case reduce NOx emissions.

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4

Spangelo, Øystein. "Experimental and Theoretical Studies of a Low Nox Swirl Burner." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-310.

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Nitrogen oxides emitted to the atmosphere can cause health problems for humans and environmental problems such as acid rain and global warming. The main part of the world energy consumption involves combustion; hence nitrogen oxide abatement in combustion is an important research field. Formation and reduction of NO_xin combustion and the current regulations on NO_x emissions are reviewed.

A novel low NO_xswirl stabilized gas burner concept, the Swirl Burner, has been studied experimentally, theoretically and numerically. Flame stabilization, rapid air and fuel mixing and internal flue gas recirculation are provided by a strongly swirling flow generated in this patented burner concept. NO_xemissions have been measured below 25 and 45 ppmv dry corrected to 3% O₂ in the flue gases using methane and propane as fuel respectively.

Studying the effect of varying geometrical parameters on the emissions of NO_x, fuel and air supply pressure and flame stability, have resulted in an optimized burner design. The optimized Swirl Burner has successfully been scaled from a 200 kW burner down to a 20 kW burner and up to a 370 kW burner, using a constant velocity scaling criteria which is the most commonly used scaling criteria for industrial burners. Experiments with the scaled burners have revealed that the fuel to air momentum should be preserved while scaling the burner. The 200 kW and the 370 kW burners were operated stable with the boiler to burner diameter (confinement) ratio in the range 5.3-6.7. The 20 kW burner, which was operated in an un-cooled and a water-cooled combustion chamber with confinement ratio of 8.1, was found to have a narrower range of stable operation with regards to thermal throughput. High post-flame heat extraction, which is enhanced by increased confinement ratio and combustion chamber cooling, reduces the emissions of NO_x, but might cause flame instabilities.

NO_x emissions measured from the three Swirl Burners scale well with NO_x scaling correlations based on flame volume as a leading-order parameter for NO_x formation (Weber, 1996). The correlations consider the effect of heat extraction on flame volume and emissions of NO_x. These correlations indicate that the heat extraction from the 20 kW burner is increasing with increasing thermal throughput. The 200 kW and the 370 kW burners were, from the correlations, found to operate with constant heat extraction.

Flame volume and shape are studied by non-intrusive measurements of OH radicals with the 20 kW burner using laser induced fluorescence. The measurements show that the flame volume is reduced with increasing thermal throughput. Measurements of NO_x from this burner also show a reduction with increasing thermal throughput. These results support the theoretical considerations of the flame volume as being the leading-order parameter for NO_xformation.

An evaluation of turbulence models and combustion models suitable for studying the Swirl Burner by computational fluid dynamics has been carried out. For this evaluation, a 2D computational model of the 20 kW burner has been used. For closure of the Reynolds Averaged Navier-Stokes equations for turbulent flow, three models have been evaluated.

These are the standard k-ε model, the RNG k-ε model and the Reynolds Stress model.

Also for modelling of combustion, three models have been evaluated, namely the Eddy Dissipation model, the Equilibrium PDF model and the Flamelet PDF model. For studying the Swirl Burner, a combination of the Reynolds Stress model and the Flamelet PDF model were found to be most suitable for modelling of turbulence and combustion respectively.

Computational results with the 20 kW burner indicate that flue gases are recirculated into a central toroidal recirculation zone downstream the burner exit. The computations are further compared with the OH concentrations measured with laser induced fluorescence.

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5

Hamedi, Naser. "Numerical Study of NOx and Flame Shape of a DLE Burner." Thesis, Linköpings universitet, Mekanisk värmeteori och strömningslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-86412.

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For natural gas combustion, there is a large amount of experience in the gas turbine industry. However, much of the design work is based on costly combustion tests due to insufficient accuracy of existing prediction tools for data such as emissions and effects due to fuel composition. In the present work, Computational Fluid Dynamics (CFD) approach is used to study partially premixed combustion in the 3rd generation DLE (Dry Low Emission) burner that is used in SGT-700 and SGT-800 gas turbines. The fuels that are studied here are natural gas and enriched hydrogen fuel. The CFD models which are used in this work are an axisymmetric and a 3D model and the softwares are ANSYS CFX and ANSYS FLUENT. One of the main objectives of this thesis is the study of flame shape and NOx emission in hydrogen enriched combustion. In the first study of the present work, effect of adding hydrogen to non-preheated gas combustion was investigated and the results were compared with the available measurement data. Calculated laminar burning velocity with CANTERA showed a good agreement with the experimental and numerical references. Also, the accuracy of generated flamelet libraries in CFD tools to calculate adiabatic flame temperature was compared with different available tools. Results showed good agreement between available tools for the ranges of interest. In addition, flame shape and NOx prediction was studied in the gas turbine burner. Adding hydrogen to the fuel increased significantly turbulent burning velocity and OH distribution in the domain. The effect of hydrogen on the central stagnation point was studied and the simulation results did not show a significant effect on the stagnation point location. Beside the flame shape, this study showed that although the CFD NOx prediction tools in ANSYS CFX and ANSYS FLUENT predict the trend of NOx and the flame propagation in the right manner, in order to use as a reliable prediction tool in the gas turbine industry they need to be improved.

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6

Wu, Chunyang. "Fuel-NOx Formation during Low-Grade Fuel Combustion in a Swirling-Flow Burner." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1165.pdf.

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7

Yimer, Ibrahim A. "Turbulent mixing in a low-NOx multi-jet burner, experimental and mathematical modelling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0002/NQ27863.pdf.

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8

Haynes, Joel M. "Aerodynamic design of no NOx oil diffusion flames using the radially stratified flame core burner." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11224.

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9

SHANG, Hai, Hiromu SUZUKI, Kazuhiro YAMAMOTO, 海. 商, 祐夢鈴木, and 和弘山本. "多噴孔ノズルバーナの燃焼特性と燃焼排出物の評価." 一般社団法人日本機械学会, 2013. http://hdl.handle.net/2237/19317.

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10

Cvoro, Valentina. "Experimental and numerical analysis of isothermal turbulent flows in interacting low NOx burners in coal-fired furnaces." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/2020.

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Coal firing power stations represent the second largest source of global NOx emissions. The current practice of predicting likely exit NOx levels from multi-burner furnaces on the basis of single burner test rig data has been proven inadequate. Therefore, to further improve current NOx reduction technologies and assist in the assessment of NOx levels in new and retrofit plant cases, an improved understanding of the impact of burner interactions is required. The aim of this research is two-fold: firstly, to experimentally investigate isothermal flow interactions in multi-burner arrays for different swirl directions and burner pitches in order to gain a better understanding of burner interaction effects within multi-burner furnaces. Secondly, to carry out numerical modelling in order to determine turbulence models which give the best agreement to experimental data. Experimental investigations were carried out using flow visualisation for qualitative and 3D laser Doppler anemometry for quantitative measurements. Numerical modelling was performed using the computational fluid dynamics software, Fluent, to compare performance between k-ε, k- ω and RSM turbulence models. Experimental investigation showed that the recirculation zone of the chequerboard configuration is more sensitive to the change in pitch than that of the columnar configuration. Further, it was found that the smaller pitch is more sensitive to change in configuration than the wider pitch. The analysis of fluctuating components, u’, v’ and w’ showed that the burner flow is highly anisotropic at burner exit. Numerical investigation showed that the k-ω turbulence model consistently performed below the other two models. The statistical comparison between k-ε and RSM turbulence models revealed that, for prediction of the swirl velocity profiles, the RSM model overall performed better than the k-ε turbulence model. The visual and statistical analyses of turbulent kinetic energy profiles also showed that the RSM turbulence model provides a closer match to the experimental data than the k-ε turbulence model.

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11

Kaufman, Kelsey Leigh. "Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames." Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4661.

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Low swirl burners (LSBs) have gained popularity in heating and gas power generation industries, in part due to their proven capacity for reducing the production of NOx, which in addition to reacting to form smog and acid rain, plays a central role in the formation of the tropospheric ozone layer. With lean operating conditions, LSBs are susceptible to combustion instability, which can result in flame extinction or equipment failure. Extensive work has been performed to understand the nature of LSB combustion, but scaling trends between laboratory- and industrial-sized burners have not been established. Using hydrogen addition as the primary method of flame stabilization, the current work presents results for a 2.54 cm LSB to investigate potential effects of burner outlet diameter on the nature of flame stability, with focus on flashback and lean blowout conditions. In the lean regime, the onset of instability and flame extinction have been shown to occur at similar equivalence ratios for both the 2.54 cm and a 3.81 cm LSB and depend on the resolution of equivalence ratios incremented. Investigations into flame structures are also performed. Discussion begins with a derivation for properties in a multicomponent gas mixture used to determine the Reynolds number (Re) to develop a condition for turbulent intensity similarity in differently-sized LSBs. Based on this requirement, operating conditions are chosen such that the global Reynolds number for the 2.54 cm LSB is within 2% of the Re for the 3.81 cm burner. With similarity obtained, flame structure investigations focus on flame front curvature and flame surface density (FSD). As flame structure results of the current 2.54 cm LSB work are compared to results for the 3.81 cm LSB, no apparent relationship is shown to exist between burner diameter and the distribution of flame surface density. However, burner diameter is shown to have a definite effect on the flame front curvature. In corresponding flow conditions, a decrease in burner diameter results a broader distribution of curvature and an increased average curvature, signifying that compared to the larger 3.81 cm LSB, the flame front of the smaller burner contains tighter, smaller scale wrinkling.

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12

UEJIMA, Mitsuhiro, Hiroshi YAMASHITA, Hisaharu OSHIMA, Kazuhiro YAMAMOTO, Yuji KANAGAWA, 光浩上島, 博史山下, 久治大島, 和弘山本, and 裕司金川. "旋回噴流燃焼器のすすとNOxの測定および数値解析による火炎構造の検討." 一般社団法人日本機械学会, 2008. http://hdl.handle.net/2237/19797.

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13

Zejda, Vojtěch. "Měření rychlostních profilů za vířičem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232121.

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A burner is very important device in process furnaces that significantly affect the production of emissions during the combustion process. One of the key things in development of the modern low-NOX burners is the evaluation of flow field downstream of an axial blade swirler inside the burner. The computational fluid dynamics (CFD) is often used to predict the attributes of the flow. Predicted values should be validated with measurement. It is the reason why the velocity fields for several choosen swirlers were measured. The hot wire anemometry was choosen and the dual-sensor probe was used during the measurement. The data can be then used for CFD validation. This thesis describes procedure of measurement set-up. The experimental facility was designed according to the anemometry method. The new probe traversing system was designed, which provides desired accuracy. Five different swirlers were measured. Large data set, need for customized post-processing and control over calculation procedures lead to new software design. For each swirler the velocity profiles were gathered and the swirl numbers calculated. That final data were transferred in to graphical format. Uncertainty of measured data was calculated. Results show counter-rotating flow in some areas closed to the swirler. Some drawbacks of current measurement set-up are discussed. Based on the thesis reader can obtain the information and knowledge for consequent measurements of swirl burners velocity profiles.

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Kříž, Tomáš. "Přepočet kotle při dílčím výkonu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228704.

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The topic of this thesis is the calculation of the steam-boiler. The begining of the thesis deals with stoichiometric calculations. In the second chapter is performed the heat balance of the boiler. In the fourth and fifth chapter are defined dimensions of the fire and is established the temperature of a combustion gas in the outlet from the fire. The fifth chapter includes the balance calculations of the particular heating surfaces of the steam-boiler. As a conclusion of the calculations of the steam-boiler is performed the total balance. In the last chapter are proposed the methods for a reduction of the quantity of NOx contained in the combustion gas.

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Nykodým, Jiří. "Vliv provozních parametrů spalování a konstrukčních parametrů nízkoemisního hořáku na charakteristické parametry spalovacích procesů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232142.

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The main aim of the work was the investigation of the effect of operational parameters of the combustion process (combustion air excess, primary fuel ratio) and burner constructional parameters (the pitch angle of secondary nozzles, tangential orientation of secondary nozzles towards the axis of the burner) on the formation of NOx and CO, flue gas temperature, the shape, dimensions and stability of the flame, in-flame temperatures in the horizontal symmetry plane of the combustion chamber and the amount of heat extracted from the hot combustion gases in the combustion chamber’s shell. Experimental activities were carried out in the laboratory of the Institute of Process and Environmental Engineering, which is focused on burners testing. The combustion tests were performed with the experimental low-NOx type burner, namely the two-gas-staged burner. Mathematical model developed based on the experimental data describes the dependency of NOx on the operating parameters of the combustion process and burner constructional parameters. The model shows that increasing air excess and increasing angle of tangential orientation of the secondary nozzles reduce the formation of NOx. The temperature peaks in the horizontal symmetry plane of the combustion chamber decreases with increasing combustion air excess. The thermal load to the combustion chamber’s wall along the length of the flame was evaluated for selected settings. It was validated that the thermal efficiency of is reduced when higher air excess is used.

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16

Rendon, Arturo Keer. "Fundamentals of low NOx burners." Thesis, University of Sheffield, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387763.

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17

Bělohradský, Petr. "Metody pro určování charakteristických parametrů procesů spalování na bázi experimentů a modelování." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233897.

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The present thesis is concerned with methods for determination and modeling of characteristic parameters of combustion of gaseous fuels. The focus is stressed on formation of nitrogen oxides and heat transfer from hot flue gases into combustion chamber’s walls. Experimental work, which is focused on testing of two burners with suppressed formation of nitrogen oxides, is an important part of the thesis. Its aim is to obtain data that is necessary for further processing and modeling. The work presents two methods that may be used in modeling of characteristic combustion parameters, namely the method based on statistical processing of data and the method based on computational fluid dynamics. The approaches are applied to two devices (burner with two-staged fuel supply, burner with two-staged air supply) with the objective to analyze their parameters. First approach covers detailed planning of burner test prior to its own carrying out (definition of the goal of experiment, choice of input factors and response, experimental plan) and subsequent statistical processing of experimental data. On the contrary, CFD approach offers simulations as an alternative option to traditional experimental methods. The simulation of combustion includes building of computational grid, setup of boundary conditions, turbulence model, heat transfer model and chemical kinetics. Results of simulations are compared with experimental measured data.

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18

Voonna, Kiran. "Development of discontinuous galerkin method for 1-D inviscid burgers equation." ScholarWorks@UNO, 2003. http://louisdl.louislibraries.org/u?/NOD,75.

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Thesis (M.S.)--University of New Orleans, 2003.
Title from electronic submission form. "A thesis ... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Mechanical Engineering"--Thesis t.p. Vita. Includes bibliographical references.

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19

Hosseini, S. M. Reza. "Non-linearities in the thermoacoustic response of a premixed swirl burner." Thesis, Queen Mary, University of London, 2009. http://qmro.qmul.ac.uk/xmlui/handle/123456789/1920.

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Lean premixed combustion remains one of the simplest and most effective methods of reducing NOx emissions in industrial gas turbines. Lean premixed flames are however prone to an undesirable side effect known as combustion instability, reducing lifetime or in severe cases causing irreversible damage to the turbine. Previous studies on this subject mostly concentrated on the prediction and control of linear instabilities, whereas the current study pays particular attention to the non-linear response. In this work, scaled axial and radial swirl burners were used under atmospheric conditions to investigate the characteristics of the Flame Transfer Function (FTF) between the heat release from methane/air flames and the imposed velocity fluctuations. The velocity fluctuations imposed upon the air flow of the burners encompassed frequencies of 40 to 200 Hz, each with stepwise increase of velocity amplitude, until blow-off occurred. The work was carried out with non-intrusive, phase-locked optical diagnostic techniques, such as Particle Image Velocimetry (PIV) for flow field visualisation and an Intensified Charged Couple Device (ICCD) for analysis of the OH* chemiluminescent intensity distribution of the flame. It is concluded that there are two dominant mechanisms responsible for the non-linear response of the flame for both swirler geometries at low (below 140 Hz) and high (above 140 Hz) frequencies of excitation. At low frequencies the flame response is governed by equivalence ratio fluctuations due to the 'stiff' fuel system and volumetric fluctuations of the input air caused by the forcing. At high frequencies the flame response is governed by the flow features such as vortex roll-up, stretching the flame over the high speed annular jet, and in some cases, causing some flame extinction.

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Kosztin, Béla. "Linear and non-linear modelling of thermoacoustic instabilities in a laboratory burner." Thesis, Keele University, 2014. http://eprints.keele.ac.uk/621/.

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Thermoacoustic instabilities are a mayor problem in industrial combustors, where they can lead to catastrophic hardware damage. An industrial gas turbine combustion chamber is a very complex and expensive system. Thus, a laboratory burner has been built for research purposes, where a large number of parameters can be varied. This study is part of the Marie Curie research network LIMOUSINE, which was set up to model thermoacoustic instabilities in the combustor chamber of gas turbines. The objective of the present thesis is to theoretically model and analyze thermoacoustic instabilities in the LIMOUSINE laboratory burner. A mathematical model of the laboratory burner has been developed. A more general form of the wave equation has been derived in the time-domain, in which the mean temperature gradient was taken into account. The governing differential equation has been solved by applying the Green’s function approach, which allows separating the effects of the unexcited burner and the fluctuating heat-release. Using perturbation techniques general solutions are given for the cases when the temperature increase is either small or large. Conclusions have been drawn about the necessary complexity of thermoacoustic models by comparing increasingly complex configurations. The forcing term of the wave equation is studied by investigating the kinematics of ducted premixed flames theoretically, and a new heat-release law is derived. Instability criterion has been derived by applying the non-linear source term. The stability parameter map of the burner has been also investigated. Expressions for the limit-cycle amplitudes and frequencies were derived using weakly non-linear theory. The predictions of the mathematical model have been compared to measurements.

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Masanja, Enock. "Study of particle motion in flows characteristic to low-NOx pulverised fuel burners." Thesis, University of Edinburgh, 1995. http://hdl.handle.net/1842/17027.

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There is no dispute that combustion by-products like sulphur dioxide, SO₂ and nitrogen oxides, NO_x, can cause environmental damage. New, tougher legislation on gas emission has started to push fundamental research work (like this project) on understanding particle/fluid dynamics in combustion and related systems to the fore front. The knowledge gained will not only offer immediate help in the control and abatement of gas emission, but also the data obtained will complement the available empirical (industrial) knowledge of roping behaviour which will be valuable in developing new numerical models and/or verifying existing ones. A test facility delivering up to 40 m/s in a 4 inch glass test section was designed, fabricated, assembled and tested. This includes swirl generators for generating swirl of 0.2 to 1.35 theoretical swirl numbers. The facility also includes a particle feed section, cyclone separator for recovering the particles and a dual pulsed Nd:YaG laser, related optics and other equipment for use in future Particle Image Velocimetry (PIV) research. LDA and Pitot-static measurements verified that the test section was capable of delivering the planned/design velocity measurement range of 0-40 m/s. PIV experiments were done for particle jet density of 95 kg/m_-3 to 198 kg/m_-3 and the results obtained on particle jet dispersion were in good agreement with previous work showing that the centre line velocity showed less fluctuation and that jets that are less dense disperse more than the denser ones.

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22

Yamashita, Hiroshi, Naoki Hayashi, Yusuke Isobe, Shinya Kato, and Kazuhiro Yamamoto. "Lifted flame structure of coannular jet flames in a triple port burner." Elsevier, 2011. http://hdl.handle.net/2237/20041.

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23

Engbers, Ralf [Verfasser], and Martin [Akademischer Betreuer] Burger. "Non-negative matrix factorization for dynamic positron emission tomography / Ralf Engbers ; Betreuer: Martin Burger." Münster : Universitäts- und Landesbibliothek Münster, 2019. http://d-nb.info/1175506494/34.

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24

Burge, Eric William. "Sound Design for Non-fiction Film and Video: A Discussion of Methodology, Perception, and Ethics." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/burge/BurgeE1207.pdf.

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Traditional documentary films, particularly science and natural history works, presume to authentically or legitimately convey accurate representations of historical events that actually occurred at a prior time. Factual and convincing representations are not necessarily congruent, and a film's merit of authenticity is often based on the perceived validity of the visual content represented. While visual imagery dominates a presentation's general delivery, a film's sound design is a fundamental structural element that is often overlooked or less scrutinized with regard to factual or accurate recounting of these same historical events. The purpose of this thesis is to examine methodologies of sound acquisition and reproduction and to discuss how various acoustic contents are perceived in relation to associated visual elements. While discerning viewers may notice critical discrepancies in picture contents that may invalidate a film's credibility, a complex matrix of sonic elements does not lend itself to deconstruction as easily. Thorough analysis of a science and natural history film must include an examination of its complete sound design. Consideration must be given to the ethical implications of using any synthesized or borrowed audio tracks if such a work is to be considered as "factual" documentary. The standards of acceptance or rejection should be no different than those associated with fabricating unnatural or contrived visual contents, no matter how compelling may be the end product.

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Martin, Cassia Graye. "The non-event, the event and techniques of representation in the novels of Frances Burney." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225797.

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Frances Burney is often praised for her skills at capturing faithful portraits of contemporary society in her novels. Yet throughout her narratives are many scenes of unnatural, improbable and violent events which are normally associated with earlier traditions of romantic and sentimental fiction. Critics have attempted to resolve this seeming inconsistency in a variety of ways, some dismissing the strange juxtaposition as artistic immaturity. More recently critics have argued for a multifaceted Burney, who implements both scenes of sensational violence and polite etiquette. Pursuing instead a narratological approach, this thesis examines four innovative techniques that Burney uses to present sensational events in unconventional ways: the Non-Event technique, the Off-Page Event technique, the Split-Focus Event technique, and the Almost-Event technique. By using these narrative methods while foregrounding the conventionality of her plot material and working against generic expectations, Burney develops new ways of focusing the text upon the protagonist. Thus rather than the sensational events being evidence of her inability to liberate herself from earlier non-realistic traditions, they are instead an essential element to her influential methods of capturing 'life'.

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KoÌˆpke, Uwe Gerhard. "Condition monitoring of buried gas pipes using a vibrating PIG." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259460.

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Owens, Aaron M. "“The Price of a Woolworth’s Burger:” The Importance and Overshadowing of the Nashville Sit-Ins." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etd/1210.

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This thesis examines the sit-in demonstrations that used direct action and civil disobedience to target segregation at store lunch counters. The Nashville demonstrations were the last sit-in protests to occur that are discussed in this thesis, which also examines the protests in Wichita and Greensboro. Historians argue that the Wichita and Greensboro sit-ins were the most important demonstrations of their kind. The movement in Wichita was the first protest to end segregation policies at targeted stores, and the Greensboro protests led to a direct action movement in over fifty other cities targeting lunch counters. However, the Nashville based sit-ins surpassed the other two cities in planning and organization, demonstrations, and ending results following the protests. This thesis will provide a historical analysis of events in America’s past that led to the sit-in movement; the thesis will also examine the movements within the three cities.

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Nguyen, Vinh Q. "A Numerical Study of Burgers' Equation With Robin Boundary Conditions." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31285.

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This thesis examines the numerical solution to Burgers' equation on a finite spatial domain with various boundary conditions. We first conduct experiments to confirm the numerical solutions observed by other researchers for Neumann boundary conditions. Then we consider the case where the non-homogeneous Robin boundary conditions approach non-homogeneous Neumann conditions. Finally we numerically approximate the steady state solutions to Burgers' equation with both the homogeneous and non-homogeneous Robin boundary conditions.
Master of Science

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You, Rong. "Modelling buried pipelines in freezing soils using non-linear Fourier finite elements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0028/MQ31405.pdf.

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Shu, Yupeng. "Numerical Solutions of Generalized Burgers' Equations for Some Incompressible Non-Newtonian Fluids." ScholarWorks@UNO, 2015. http://scholarworks.uno.edu/td/2051.

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The author presents some generalized Burgers' equations for incompressible and isothermal flow of viscous non-Newtonian fluids based on the Cross model, the Carreau model, and the Power-Law model and some simple assumptions on the flows. The author numerically solves the traveling wave equations for the Cross model, the Carreau model, the Power-Law model by using industrial data. The author proves existence and uniqueness of solutions to the traveling wave equations of each of the three models. The author also provides numerical estimates of the shock thickness as well as maximum strain $\varepsilon_{11}$ for each of the fluids.

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SEREBRENICK, GUSTAVO. "STABILITY ANALYSIS OF SLENDER COLUMNS PARTIALLY BURIED IN A NON-LINEAR ELASTIC FOUNDATION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6168@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
O presente trabalho tem por objetivo estudar o comportamento de colunas esbeltas parcialmente enterradas, quando submetidas a um carregamento axial de compressão. A fundação é representada, ora por um modelo linear, o qual considera que a reação exercida pelo solo é proporcional às deflexões da coluna, ora por um modelo não-linear no qual esta relação de proporcionalidade não é mais verificada. Para a modelagem da coluna, é usada a teoria inextensional de barras esbeltas. Inicialmente, mostra-se como são deduzidas as equações diferenciais do problema a partir dos funcionais de energia da coluna. No problema linear, buscam-se obter as cargas críticas e modos críticos da coluna. Neste caso, sua solução analítica é encontrada a partir da resolução do problema de valor de contorno usando-se um programa de álgebra simbólica. Também é obtida uma solução aproximada através do método de Ritz. Um estudo paramétrico detalhado analisa a influência das condições de apoio da coluna e altura e rigidez da fundação na carga e modo críticos. Entretanto, no caso nãolinear, as equações diferenciais são mais complexas, não permitindo a obtenção de uma solução analítica. É utilizado, então, o método de Ritz, no qual as soluções analíticas obtidas para o problema linear (autofunções) são usadas como funções de interpolação. Em seguida, chega-se à uma equação não- linear de equilíbrio, da qual se obtém o caminho pós-crítico da coluna. Os resultados do problema nãolinear são comparados com os obtidos através do método dos elementos finitos.
In this thesis the behavior of slender, partially embedded columns under axial compressive forces is studied. The foundation is either represented by a linear model, which considers that the soil reaction is proportional to the column’s deflections or by a non-linear model in which this proportionality relation is not observed. The inextensional slender beam theory is used to model the column. Initially, the governing differential equations are deduced from the energy functional of the column-foundation system. In the linear problem, the critical loads and corresponding critical modes are looked for. In this case, an analytic solution is obtained by the solution of the associated boundary value problem, using a symbolic algebra software. An approximate solution is also found by Ritz’s method. A parametric study is conducted to study the influence of the column boundary conditions and foundation’s height and stiffness on critical loads and modes. However, in the non-linear case, differential equations are much more complex and an analytical solution is not possible. So, the Ritz’s method is used once again, in which the analytic solutions of the linear problem (eigenfunctions) are used as interpolation functions. After that, a non-linear equilibrium equation is obtained together with the column post-buckling path. These results are compared with the ones obtained using the finite element method.

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Li, Zhiyi. "Sub-grid models for Large Eddy Simulation of non-conventional combustion regimes." Doctoral thesis, Universite Libre de Bruxelles, 2019. https://dipot.ulb.ac.be/dspace/bitstream/2013/286444/5/contratZL.pdf.

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Novel combustion technologies ensuring low emissions, high efficiency and fuel flexibility are essential to meet the future challenges associated to air pollution, climate change and energy source shortage, as well as to cope with the increasingly stricter environmental regulation. Among them, Moderate or Intense Low oxygen Dilution (MILD) combustion has recently drawn increasing attention. MILD combustion is achieved through the recirculation of flue gases within the reaction region, with the effect of diluting the reactant streams. As a result, the reactivity of the system is reduced, a more uniform reaction zone is obtained, thus leading to decreased NOx and soot emissions. As a consequence of the dilution and enhanced mixing, the ratio between the mixing and chemical time scale is strongly reduced in MILD combustion, indicating the existence of very strong interactions between chemistry and fluid dynamics. In such a context, the use of combustion models that can accurately account for turbulent mixing and detailed chemical kinetics becomes mandatory.Combustion models for conventional flames usually rely on the assumption of time-scale separation (i.e. flamelets and related models), which constrain the thermochemical space accessible in the numerical simulation. Whilst the use of transported PDF methods appears still computationally prohibitive, especially for practical combustion systems, there are a number of closures showing promise for the inclusion of detailed kinetic mechanisms with affordable computational cost. They include the Partially Stirred Reactor (PaSR) approach and the Eddy Dissipation Concept (EDC) model.In order to assess these models under non-conventional MILD combustion conditions, several prototype burners were selected. They include the Adelaide and Delft jet-in-hot coflow (JHC) burners, and the Cabra lifted flames in vitiated coflow. Both Reynolds Averaged Navier Stokes (RANS) and Large Eddy Simulations (LES) were carried out on these burners under various operating conditions and with different fuels. The results indicate the need to explicitly account for both the mixing and chemical time scales in the combustion model formulation. The generalised models developed currently show excellent predictive capabilities when compared with the available, high-fidelity experimental data, especially in their LES formulations. The advanced approaches for the evaluation of the mixing and chemical time scale were compared to several conventional estimation methods, showing their superior performances and wider range of applications. Moreover, the PaSR approach was compared with the steady Flamelet Progress Variable (FPV) model on predicting the lifted Cabra flame, proving that the unsteady behaviours associated to flame extinction and re-ignition should be appropriately considered for such kind of flame.Because of the distributed reaction area, the reacting structures in MILD combustion can be potentially resolved on a Large Eddy Simulation (LES) grid. To investigate that, a comparative study benchmarking the LES predictions for the JHC burner obtained with the PaSR closure and two implicit combustion models was carried out, with the implicit models having filtered source terms coming directly from the Arrhenius expression. Theresults showed that the implicit models are very similar with the conventional PaSR model on predicting the flame properties, for what concerns the mean and root-mean-square of the temperature and species mass fraction fields.To alleviate the cost associated to the use of large kinetic mechanisms, chemistry reduction and tabulation methods to dynamically reduce their size were tested and benchmarked, allowing to allocate the computational resources only where needed. Finally, advanced post-processing tools based on the theory of Computational Singular Perturbation (CSP) were employed to improve the current understanding of flame-turbulence interactions under MILD conditions, confirming the important role of both autoignition and self propagation in these flames.
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished

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Xiang, Shengquan. "Stabilisation rapide d'équations de Burgers et de Korteweg-de Vries." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS422.

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Cette thèse est consacrée à l'étude de la stabilisation d'équations aux dérivées partielles par feedbacks non linéaires. Nous nous intéressons aux cas où la technique de linéarisation et l'utilisation de feedback stationnaire ne fonctionnent pas pour des problèmes de stabilisation, par exemple des équations de Korteweg-de Vries (KdV) et des équations de Burgers. Plus précisément, nous traitons trois cas importants : la stabilisation de systèmes non linéaires dont les systèmes linéarisés ne sont pas stabilisables asymptotiquement ; la stabilisation locale en temps petit de systèmes contrôlables linéaires ; la stabilisation globale en temps petit de systèmes contrôlables non linéaires. En particulier, nous trouvons une stratégie pour la stabilisation globale en temps petit de l'équation de Burgers visqueuse. Elle repose sur la stabilisation globale approchée en temps petit et sur la stabilisation locale en temps petit. De plus, nous prouvons que le système de KdV même pour des longueurs critiques est stabilisable de manière exponentielle. Nous utilisons pour cela une structure quadratique de la dynamique de la partie dont le linéarisé n'est pas contrôlable
This thesis is devoted to the study of stabilization of partial differential equations by nonlinear feedbacks. We are interested in the cases where classical linearization and stationary feedback law do not work for stabilization problems, for example KdV equations and Burgers equations. More precisely, it includes three important cases : stabilization of nonlinear systems whose linearized systems are not asymptotically stabilizable ; small-time local stabilization of linear controllable systems ; small-time global stabilization of nonlinear controllable systems. We find a strategy for the small-time global stabilization of the viscous Burgers equation : small-time global approximate stabilization and small-time local stabilization. Moreover, using a quadratic structure, we prove that the KdV system is exponentially stabilizable even in the case of critical lengths

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Park, Doyoub. "EFFECTS OF TRANSPORT PROPERTIES AND FLAME UNSTEADINESS ON NITROGEN OXIDES EMISSIONS FROM LAMINAR HYDROGEN JET DIFFUSION FLAMES." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2968.

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Experimental studies on the coupled effects of transport properties and unsteady fluid dynamics have been conducted on laminar, acoustically forced, hydrogen jet diffusion flames diluted by argon and helium. The primary purpose of this research is to determine how the fuel Lewis number and the flow unsteadiness play a combined role in maximum flame temperature and affect NOx emission from jet diffusion flame. The fuel Lewis number is varied by increasing/decreasing the mole fraction of diluents in the fuel stream. Therefore, maximum flame temperatures and then NOx emission levels were expected to differ for Ar- and He-diluted flames. In an investigation of unsteady flames, two different frequencies (10 and 100 Hz) were applied to observe a behavior of NOx emission levels and flame lengths by changes of unsteady fluid dynamics and transport properties.
M.S.M.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering

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35

Altrén, Jesper, and Mattias Lyth. "Solvency II - A compliance burden or an opportunity for the Swedish non-life insurance industry?" Thesis, Linköping University, Department of Management and Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8339.

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Insurance companies and banks are of great importance to the economy, which is why their stability must be ensured. In order to prevent bankruptcies in the financial sector, these companies are subject to strict regulations, which set standards for risk management and the amount of reserve capital required. Such capital reserves act as safety buffers to protect the customers from extraordinary events. In the insurance industry, the reserve capital is referred to as the solvency margin.

Solvency II is new set of insurance regulations that aims to set a common standard regarding solvency capital and risk management for insurance companies within the European Union. The potential costs and benefits of the regulations are of importance not only to insurance companies but also to those firms that offer services and products to the insurance industry in the field of risk management. Solvency II is often compared to the Basel II accord for banks, which had a strong business case in the way that banks could significantly lower their reserve capital and use it for other purposes. The question is, however, whether insurance companies can expect similar benefits from Solvency II.

The purpose of this study is therefore to explain how the Solvency II regulations will affect risk management in the Swedish non-life insurance industry, and whether these changes can result in opportunities for insurance companies. This is achieved by studying the new regulations and conducting a number of interviews with insurance company representatives as well as industry experts. Four potential effects of Solvency II have been investigated: capital levels, insurance pricing, credit ratings and reinsurance.

The findings of the study indicate that no obvious benefits related to the potential effects above can be realised by complying with Solvency II. The future capital requirements will come close to those already enforced by supervisors today, resulting in a minor change that can go both ways. Neither credit ratings nor reinsurance covers seem to become notably affected by Solvency II. As for insurance pricing, an increasingly sophisticated risk-based allocation of the cost of solvency capital provides the most notable opportunity of Solvency II, but at present, no conclusions can be drawn regarding the effects of such changes. On the other hand, Solvency II will put pressure on improving systems to ensure the quality and traceability of data.

Thus, the actual changes in risk management practices are not expected to be substantial among Swedish non-life insurance companies, and it therefore seems unlikely that insurance companies would be willing to invest as heavily in reaching Solvency II compliance as banks have done in Basel II.

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Rogner, Sam. "Too Many Cooks Spoil the Broth? : Burden Sharing and Effectiveness in Peacekeeping Operations." Thesis, Uppsala universitet, Institutionen för freds- och konfliktforskning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353715.

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This paper examines the effect of burden sharing in peacekeeping operations (both among contingent troops and in the entirety of the mission) and effectiveness, specifically whether a party chooses to renege on a peace agreement. The author hypothesizes that burden sharing will make it less likely that a party reneges on a peace agreement. The theoretical argument made in the paper is that burden sharing will help in solving the commitment problem inherent to peace agreements, by signaling to the combatants that the peacekeeping mission is there to stay (and won’t be vulnerable to a potential withdrawal from an important contributor), as well as signaling that there is international support for punishing measures against a party who would renege on the agreement. The paper examines all peacekeeping missions that deployed following a peace agreement between 1992-2016 using data on peacekeeping contributions from the United Nations. The hypotheses will however not be supported by the empirics. In fact there is limited evidence for burden sharing among contingent troops to increase the likelihood that a party chooses to renege on a peace agreement, while burden sharing among all personnel (military and civilian) have no effect on the matter.

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Redmon, Jessica. "Stochastic Bubble Formation and Behavior in Non-Newtonian Fluids." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case15602738261697.

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Hislop, Gregory Francis. "Diffraction Tomographic Imaging of Shallowly Buried Targets using Ground Penetrating Radar." Queensland University of Technology, 2005. http://eprints.qut.edu.au/16125/.

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The problem of subsurface imaging with Ground Penetrating Radar (GPR) is a challenging one. Due to the low-pass nature of soil sensors must utilise wave-lengths that are of the same order of magnitude as the object being imaged. This makes imaging difficult as straight ray approximations commonly used in higher frequency applications cannot be used. The problem becomes even more challenging when the target is shallowly buried as in this case the ground surface reflection and the near-field parameters of the radar need to be considered. This thesis has investigated the problem of imaging shallowly buried targets with GPR. Two distinct problems exist in this field radar design and the design of inverse scattering techniques. This thesis focuses on the design of inverse scattering techniques capable of taking the electric field measurements from the receiver and providing accurate images of the scatterer in real time. The thesis commences with a brief introduction to GPR theory. It then provides an extensive review of linear inverse scattering techniques applied to raw GPR data. As a result of this review the thesis draws the conclusion that, due to its strong foundations in Maxwell's equations, diffraction tomography is the most appropriate approach for imaging shallowly buried targets with GPR. A three-dimensional diffraction tomographic technique is then developed. This algorithm forms the primary contribution of the thesis. The novel diffraction tomography technique improves on its predecessors by catering for shallowly buried targets, significant antenna heights and evanescent waves. This is also the first diffraction tomography technique to be derived for a range of antenna structures. The advantages of the novel technique are demonstrated first mathematically then on synthetic and finally practical data. The algorithm is shown to be of high practical value by producing accurate images of buried targets in real time.

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Knahr, Christina. "Participation of non-state actors in the dispute settlement system of the WTO: benefit or burden? /." Frankfurt am Main [u.a.] : Lang, 2007. http://www.gbv.de/dms/spk/sbb/recht/toc/525118349.pdf.

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40

Evans, Ruthven Clive Philip. "Acoustic penetration of the seabed, with particular application to the detection of non- metallic buried cables." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310723.

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Adeloye, Davies Olubunmi. "Estimating the burden of selected non-communicable diseases in Africa : a systematic review of the evidence." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/21090.

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Background The burden of non-communicable diseases (NCDs) is rapidly increasing globally, and particularly in Africa, where the health focus, until recently, has been on infectious diseases. The response to this growing burden of NCDs in Africa has been affected owing to a poor understanding of the burden of NCDs, and the relative lack of data and low level of research on NCDs in the continent. Recent estimates on the burden of NCDs in Africa have been mostly derived from modelling based on data from other countries imputed into African countries, and not usually based on data originating from Africa itself. In instances where few data were available, estimates have been characterized by extrapolation and over-modelling of the scarce data. It is therefore believed that underestimation of NCDs burden in many parts of Africa cannot be unexpected. With a gradual increase in average life expectancy across Africa, the region now experiencing the fastest rate of urbanization globally, and an increase adoption of unhealthy lifestyles, the burden of NCDs is expected to rise. This thesis will, therefore, be focussing on understanding the prevalence, and/or where there are available data, the incidence, of four major NCDs in Africa, which have contributed highly to the burden of NCDs, not only in Africa, but also globally. Methods I conducted a systematic search of the literature on three main databases (Medline, EMBASE and Global Health) for epidemiological studies on NCDs conducted in Africa. I retained and extracted data from original population-based (cohort or cross sectional), and/or health service records (hospital or registry-based studies) on prevalence and/or incidence rates of four major NCDs in Africa. These include: cardiovascular diseases (hypertension and stroke), diabetes, major cancer types (cervical, breast, prostate, ovary, oesophagus, bladder, Kaposi, liver, stomach, colorectal, lung and non-Hodgkin lymphoma), and chronic respiratory diseases (chronic obstructive pulmonary disease (COPD) and asthma). From extracted crude prevalence and incidence rates, a random effect meta-analysis was conducted and reported for each NCD. An epidemiological model was applied on all extracted data points. The fitted curve explaining the largest proportion of variance (best fit) from the model was further applied. The equation generated from the fitted curve was used to determine the prevalence and cases of the specific NCD in Africa at midpoints of the United Nations (UN) population 5-year age-group population estimates for Africa. Results From the literature search, studies on hypertension had the highest publication output at 7680, 92 of which were selected, spreading across 31 African countries. Cancer had 9762 publications and 39 were selected across 20 countries; diabetes had 3701 publications and 48 were selected across 28 countries; stroke had 1227 publications and 19 were selected across 10 countries; asthma had 790 publications and 45 were selected across 24 countries; and COPD had the lowest output with 243 publications and 13 were selected across 8 countries. From studies reporting prevalence rates, hypertension, with a total sample size of 197734, accounted for 130.2 million cases and a prevalence of 25.9% (23.5, 34.0) in Africa in 2010. This is followed by asthma, with a sample size of 187904, accounting for 58.2 million cases and a prevalence of 6.6% (2.4, 7.9); COPD, with a sample size of 24747, accounting for 26.3 million cases and a prevalence of 13.4% (9.4, 22.1); diabetes, with a sample size of 102517, accounting for 24.5 million cases and a prevalence of 4.0% (2.7, 6.4); and stroke, with a sample size of about 6.3 million, accounting for 1.94 million cases and a prevalence of 317.3 per 100000 population (314.0, 748.2). From studies reporting incidence rates, stroke accounted for 496 thousand new cases in Africa in 2010, with a prevalence of 81.3 per 100000 person years (13.2, 94.9). For the 12 cancer types reviewed, a total of 775 thousand new cases were estimated in Africa in 2010 from registry-based data covering a total population of about 33 million. Among women, cervical cancer and breast cancer had 129 thousand and 81 thousand new cases, with incidence rates of 28.2 (22.1, 34.3) and 17.7 (13.0, 22.4) per 100000 person years, respectively. Among men, prostate cancer and Kaposi sarcoma closely follows with 75 thousand and 74 thousand new cases, with incidence rates of 14.5 (10.9, 18.0) and 14.3 (11.9, 16.7) per 100000 person years, respectively. Conclusion This study suggests the prevalence rates of the four major NCDs reviewed (cardiovascular diseases (hypertension and stroke), diabetes, major cancer types, and chronic respiratory diseases (COPD and asthma) in Africa are high relative to global estimates. Due to the lack of data on many NCDs across the continent, there are still doubts on the true prevalence of these diseases relative to the current African population. There is need for improvement in health information system and overall data management, especially at country level in Africa. Governments of African nations, international organizations, experts and other stakeholders need to invest more on NCDs research, particularly mortality, risk factors, and health determinants to have evidenced-based facts on the drivers of this epidemic in the continent, and prompt better, effective and overall public health response to NCDs in Africa.

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Yamashita, Hugo Tubone. "A alteração das circunstâncias fáticas nos contratos interempresariais." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/2/2131/tde-08122015-083858/.

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A presente dissertação volta-se à análise da alteração superveniente das circunstâncias fáticas, especificamente, em contratos interempresariais. Tais contratos, compreendidos como aqueles em que, ao menos, uma das partes é ente empresarial e ambos os contratantes visam auferir lucro, têm características distintas de outros contratos de natureza civil (contratos existenciais), mormente no que se refere à assunção de riscos pelas partes envolvidas. Dado o caráter arriscado da atividade empresarial, a intervenção exógena nos contratos interempresariais visando à tutela dos contratantes deve ser reduzida, de forma a se privilegiar tanto quanto possível a força obrigatória dos contratos (pacta sunt servanda). Nessa medida, as nuances dos contratos interempresariais, em conjunto com a imprescindível atividade estatal de regulação do mercado (fenômeno poliédrico), demandam uma aplicação diferenciada do modelo da onerosidade excessiva previsto nos artigos 478 a 480 do Código Civil, sob pena de desvirtuamento da lógica empresarial e desestímulo ao tráfico mercantil. O primeiro capítulo deste trabalho é destinado à individualização dos principais vetores da atividade empresarial e os respectivos reflexos daqueles na formação dos contratos empresariais. Em seguida, no segundo capítulo da empreitada, são analisadas as teorias revisionistas de maior influência na construção do modelo de onerosidade excessiva brasileiro, bem como as especificidades do próprio modelo em si. Por fim, o terceiro e conclusivo capítulo visa à identificação do suporte fático da onerosidade excessiva em contratos empresariais, bem como à análise dos efeitos decorrentes da aplicação do modelo a referidas formas de contratação.
This dissertation is focused on the analysis of the change of circumstances, regarding specifically entrepreneurial contracts. These contracts, understood as those in which at least one of the parties involved is an entrepreneurial entity and both of the parties seek to obtain profits with the deal, can be defined by distinguished characteristics when compared to civil contracts in general (contratos existenciais), mainly when it comes to the risk assumption by the parties in the contract. Given the risk inherent to business activities, the exogenous intervention in entrepreneurial contracts aiming the protection of one of the parties should be reduced as much as possible, in such a way to respect the binding force of the contracts (pacta sunt servanda). Accordingly, the specificities of the entrepreneurial contracts, together with the indispensable public regulation of the market (polyhedral phenomenon), require a distinguished applicability of the rules provided by the Brazilian Civil Code under the articles 478 to 480, otherwise entrepreneurial rationality of commercial contracts may be ruined and, as a result, the commercial traffic discouraged. The first chapter of this study is dedicated to finding the main features of the business activity and their implications to the formation of entrepreneurial contracts. Subsequently, in the second chapter of the essay, the theories related to change of circumstances that most influenced the construction of a Brazilian theory are analyzed, as well as the peculiarities of the Brazilian theory itself. Finally, the third and concluding chapter seeks to identify the hypothesis provided by articles 478 to 480 for entrepreneurial contracts, as well to analyze the effects arising from the application of this set of rules to referred contracts.

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Chundu, Mwanja. "Perceived parenting style and suicidal/Non-suicidal self-Injury in students at the University of Cape Town." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/33601.

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Background: Low- and middle-income countries like South Africa carry the greatest suicide burden, with local general population suicide attempt rates of 2.9–22.7%, in comparison to 0.7–9% in international literature. Non-suicidal self-injury (NSSI) commonly co-occurs with suicidal behaviours and estimates range from 5.5% internationally to 19.4% in South Africa. As a subgroup of the general population, university students are at higher risk both of suicidal behaviours and NSSI (S/NSSI). Risk factors for S/NSSI include parenting style; however, very little is known about the relationship between parenting styles and S/NSSI in university students in the South African context. Objectives: In this dissertation we set out to perform a literature review relating to explanatory models and risk factors associated with S/NSSI and then proceeded to collect novel data from students at the University of Cape Town. This research study aimed to describe the rates of S/NSSI behaviours and to explore the relationship between the Baumrind parenting style typography and S/NSSI in university students. The study hypothesised that authoritative parenting would negatively correlate with S/NSSI. No a priori hypotheses were made about the other parenting styles investigated. Methods: In chapter 1, we performed a literature review of peer-reviewed publications on Pubmed, Psychinfo via EBSCOHost and MEDLINE via EBSCOHost identified through search terms that were relevant to the focus of the study. In chapter 2 novel data were collected. Students from all faculties at the University of Cape Town were invited to complete an anonymous, online electronic survey. Data collection included a socio-demographic questionnaire, Parenting Styles and Dimensions Questionnaire and Self-Harming Behaviours Questionnaire. Descriptive statistics quantified parenting styles, suicidal behaviours and NSSI. Spearman's correlation coefficients examined the association between parenting style and S/NSSI. Results: Literature review provided a topline review of explanatory models and risk factors associated with S/NSSI and identified relevant literature about parenting styles using the Baumrind typology. In the electronic survey of university students, the rate of suicidal attempts was 6.3% and of NSSI was 22.7%. Suicide threats, suicidal thoughts, and thoughts of dying were reported by 5.9%, 35.7% and 50.7% respectively. No significant differences were seen between male and female students. We observed no significant association between authoritative parenting and suicidal behaviours, but authoritative mothers and fathers were significantly associated with a history of NSSI. Both permissive mothers and fathers were associated with suicide attempts, threats, and thoughts, whereas only permissive mothers were associated with NSSI. Conclusion: This study replicated previously reported high rates of S/NSSI in South African university students in comparison to general population and international data. Contrary to our hypothesis, authoritative parenting style was positively correlated with NSSI, but not with suicidal behaviours. Further studies are warranted to examine parenting style, and permissive parenting, in particular, in relation to S/NSSI

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D'ANIELLO, GUIDO EDOARDO. "DEMENZA E QUALITA' DELLA VITA: INTERVENTI NON FARMACOLOGICI PER I PAZIENTI E PER I FAMILIARI." Doctoral thesis, Università Cattolica del Sacro Cuore, 2019. http://hdl.handle.net/10280/59475.

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Il presente elaborato si colloca entro l’area di ricerca sull’invecchiamento patologico, con particolare riferimento al paziente con diagnosi di demenza moderata e grave e al relativo caregiver; tema centrale è la qualità della vita dei due membri della diade paziente/familiare, e la necessità di diversificare e arricchire l’attività psicologica entro i contesti di ricovero a lungo termine in favore di un miglioramento del benessere della diade stessa. A tale scopo, il lavoro si articola in due studi distinti: nel primo, si propone un intervento di stimolazione musicale individualizzata diretta al paziente con diagnosi di demenza moderata o grave, nel secondo un intervento di reminiscenza che ha come target il familiare. La tesi si articola in tre sezioni: la prima è una cornice teorica di riferimento, la seconda e la terza espongono rispettivamente il primo e il secondo studio sperimentale. Il primo capitolo ha lo scopo di fornire un quadro teorico e empirico aggiornato in merito al tema dell’invecchiamento. Inizialmente viene trattata la questione della “Ageing Society” da un punto di vista globale, delineando nel corso del capitolo le caratteristiche e le criticità legate all’invecchiamento patologico e alla sua gestione entro il Sistema Sanitario Nazionale, con particolare interesse verso la realtà delle Residenze Sanitario-Assistenziali (RSA), contesto entro il quale si sono svolti i due lavori di ricerca proposti. Si tocca infine il tema dell’intervento non farmacologico diretto al paziente. In una seconda parte è descritta la prospettiva del familiare, il concetto di burden e il ruolo della relazione pregressa tra paziente e caregiver da un punto di vista teorico; segue la descrizione degli interventi non farmacologici diretti al caregiver finora proposti in letteratura, ideati allo scopo di alleviare stress legato al ruolo di cura e alle sue implicazioni. Il secondo capitolo ha lo scopo di esporre il primo studio della tesi, che si è occupato di verificare l’efficacia di un intervento di ascolto musicale individualizzato sulla qualità della vita di pazienti con diagnosi di demenza moderata o grave. Per questo motivo, si sono prima di tutto descritti i sintomi comportamentali della demenza, con particolare riferimento alla agitazione psicomotoria e al suo ruolo di indice dello stato psicologico del paziente con deficit cognitivi avanzati. Nella sezione empirica del capitolo viene descritta nei dettagli la modalità di intervento selezionata, gli obiettivi dello studio e i risultati ottenuti in base alla misurazione pre-post delle variabili di outcome selezionate e al confronto tra gruppo sperimentale e gruppo di controllo. Il terzo capitolo tratta il secondo studio del lavoro di tesi, che ha indagato l’efficacia di un intervento di reminiscenza sulla qualità della vita percepita dai familiari di pazienti con diagnosi di demenza afferenti alla RSA Monsignor Bicchierai – Istituto Auxologico Italiano di Milano. Allo scopo di motivare le ragioni della scelta di questa modalità di intervento, si sono descritte le premesse teoriche della teoria della reminiscenza e le sue potenzialità come forma di approccio al paziente anziano; l’idea dello studio è stata quella di applicare tale modalità di intervento sul caregiver, allo scopo di alleviare il burden percepito conseguente al carico pratico e emotivo che la cura della persona cara comporta. Analogamente al secondo capitolo, segue la sezione empirica dello studio, con un esteso approfondimento metodologico e la descrizione e discussione dei risultati ottenuti. Una sezione finale avrà lo scopo di proporre riflessioni e spunti clinici emersi da entrambi gli studi, entro una visione globale della presa in carico della diade paziente/caregiver.
This research thesis refers to pathological aging, with a particular focus on the patient with a diagnosis of dementia and his/her caregiver. The intended central theme is the patient and the caregiver’s quality of life, assuming them as a dyad; the work also concentrated on the need to diversify and enrich the psychological offer within the context of long-term hospitalization. To this end, it is divided into two separate studies. In the first one, we propose an individualized musical intervention directed to the patient with a diagnosis of moderate or severe dementia; in the second the effcacy of a reminiscence intervention that targets the family member is tested. The thesis consists of three separate sections: the first is a theoretical frame, the second and the third expose the first and the second experimental study respectively. The first chapter aims at providing an updated theoretical and empirical framework on the subject of aging. The problem of the "Aging Society" is firstly discussed; among the chapter the characteristics and the critical issues related to pathological aging and its management are debated. This topic requested a deepening into the features of the italian National Health System, with a particular focus on the reality of Nursing Homes (RSA), within which the two proposed research works were carried out. Finally, the topic of non-pharmacological intervention directed to the patient is treated. The second part describes the caregivers’ perspective, the concept of burden and the role of the prior relationship between patient and caregiver: in order to act on the stress related to the role of care and its implications, non-pharmacological interventions directed to the caregiver according to scientific literature are described. The second chapter objective is to display the first study, which aimed at testing the effectiveness of an individualized music listening intervention on the quality of life of patients diagnosed with moderate or severe dementia. For this reason, the behavioral symptoms of dementia (BPSD) were first described, with particular reference to agitation and its role as an index of the psychological state of the patient with advanced cognitive impairment. In the empirical section of the chapter the intervention is carefully described, together with the objectives of the study and the results obtained based on the pre-post measurement of the selected outcome variables and the comparison between the experimental group and the control group. The third chapter deals with the second study of the thesis work, which investigated the effectiveness of a reminiscence intervention on the caregivers’ perceived quality of life; they belonged to the RSA Monsignor Bicchierai - Italian Auxologic Institute of Milan. In order to support the choice of this modality of intervention, the theoretical premises and its potential use as a form of treatment for dementia patients have been described; the seminal idea of the study was to apply this kind of intervention on the caregiver, in order to relieve the burden resulting from the practical and emotional load requested. Similarly to the second chapter, the empirical section of the study follows, with an extensive methodological study together with a description of the obtained results. A final section had the purpose to think over the clinical ideas emerged from both studies, viewing the dyad patient-caregiver as a single care recipient.

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Wood, Nathan D. "Mystic Identifications: Reading Kenneth Burke and “Non-identification” through Asian American Rhetoric." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8482.

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Krista Ratcliffe’s term “non-identification” offers a version of identification that assumes identity is not always identifiable. As an attitude that fosters cross-cultural listening, non-identification asks us to listen to others from a place of “neutrality,” with “hesitancy,” “humility,” and “pause” in order to consider identity’s fluid nature (73). This thesis first argues that this term might also describe speaking strategies premised on non-identifiability. As I’ll show, an inventive non-identification would articulate some rhetorical strategies that neither “identification” nor “disidentification” currently articulate. However, rhetorical scholars need more theoretical and practical guidance for what this kind of speech looks like. So, this thesis also argues why, despite criticism to the contrary, the writing of Kenneth Burke offers an ideal account for inventive non-identification. Burke’s descriptions of the terms “synecdoche function,” the “mystic” and “poetic language” achieve the same effects as Ratcliffe’s non-identification, yet Burke describes these same effects from the perspective of the speaker. Following my re-reading of Burke, I ground the theory of inventive non-identification in a brief rhetorical analysis of Yan Phou Lee’s 1887 autobiography When I Was a Boy in China. By showing how this theory applies to Asian American rhetoric, I conclude that inventive non-identification has utility for the field of rhetoric more broadly.

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Cleon, Louis-Marie. "Stabilité linéaire et non linéaire des schémas de Boltzmann sur réseau simulant des écoulements visqueux compressibles." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066183/document.

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L'étude de stabilité des systèmes différentiels issus des équations de Navier-Stokes consiste à analyser la réponse du système linéarisé à une perturbation en onde plane. Elle ne peut pas rendre compte de tous les mécanismes possibles d'instabilité non linéaire. De telles analyses de stabilité non linéaire ont été abordées pour des discrétisations en différences finies de l'équation scalaire non visqueuse de Burgers. Elles sont basées sur l'analyse en ondes résonantes, en considérant un ensemble d'ondes qui forment un groupe fermé pour l'équation discrétisée. Une conclusion importante de ces travaux est que quelques mécanismes non linéaires instables existent qui échappent à l'analyse linéaire, comme le mécanisme de focalisation étudié et expliqué à l'aide des modes de side band, introduits pour amorcer les instabilités. Cette approche d'ondes résonantes est étendue à l'analyse non linéaire de stabilité pour les méthodes LBM (Lattice Boltzmann Method). Nous présentons pour la première fois une équation vectorielle à la place de l' équation scalaire de Burgers, car la méthode LBM considère une fonction de distribution par vitesses discrètes. L'application du principe des ondes résonantes aux équations de Boltzmann sur réseau pour un écoulement monodimensionnel, compressible et isotherme dans un schéma D1Q3 donne des cartes d'instabilité, dans le cas de 1 ou plusieurs modes résonants, très dépendantes des conditions initiales. Le phénomène de focalisation n'a pas été obtenu dans la formulation LBM. Des croissances transitoires dues à la non-normalité des opérateurs peuvent exister. Elles sont calculées par une méthode d'optimisation Lagrangienne utilisant les équations adjointes de LBM. L'application du principe des ondes résonantes est étendue à un modèle 2D. On montre que les instabilités deviennent prépondérantes
The stability study of differential systems derived from the Navier- Stokes equations consists in analysing the response of the planar linearized system from a disturbance on a flat wave. It cannot account for all possible mechanisms of nonlinear instability. Such non-linear stability analyses were discussed for finite difference of the scalar non-viscous Burger equation. They are based on the analysis in resonant waves, considering a set of waves that form a closed group for the discretized equation. An important conclusion of this work is that some unstable nonlinear mechanisms exist that are beyond the linear analysis, as the focusing mechanism studied and explained using the methods of side band, introduced to initiate instabilities. This approach of resonant waves is extended to non-linear stability analysis for LBM (Lattice Boltzmann Method) methods. We report for the first time a vector equation instead of the scalar Burgers equation, because the LBM method considers a distribution function by discrete speeds. The principle of resonant waves to lattice Boltzmann equations for one-dimensional flow in a compressible and isothermal D1Q3 scheme gives instability maps, in the case of one or more resonant modes , highly dependent upon the initial conditions. The phenomenon of focus has not been obtained in the LBM formulation. Transient growth due to non-normality of operators may exist. They are calculated by a Lagrangian optimization method combined with LBM equations. The principle of resonant waves is extended to a 2D model. We show that the instabilities become dominant

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Bendaas, Saïda. "Quelques applications de l'analyse non standard aux équations aux dérivées partielles." Mulhouse, 1994. http://www.theses.fr/1994MULH0298.

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Hamour, Naylah. "Estimating and comparing the burden of chronic Hepatitis C in the immigrant and the non-immigrant population in Québec." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110736.

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Background: Immigrants have higher mortality from chronic viral hepatitis and hepatocellular carcinoma as compared to those born in Canada. Approximately 20% of this burden is likely due to hepatitis C (HCV). Despite this disparity there are no screening programs to detect chronic HCV in immigrants after arrival in Canada. This is partly due to a lack of population-based data describing the burden of chronic HCV in immigrants.Methods: To fill this gap, we created a case series of all cases of chronic hepatitis C reported from 1991-2008 in Québec through linking the MADO (Québec Reportable Disease) database to 5 other Québec administrative databases; the MICC (Québec Landed Immigrants), the RAMQ (Québec provincial health insurance and physician billing) and the hospitalization databases. Reported rates were estimated using the reported number of cases in immigrants and non-immigrants during the study period. Québec census data from 1991, 1996, 2001, and 2006 (stratified by immigrant and non-immigrant status) was used for the denominator. Rates, rate ratios, and 95% CIS were calculated using the Poisson distribution. Proportions of cases with chronic hepatitis C associated complications were calculated and compared in immigrants and non-immigrants. Results: A total of 20,459 cases of chronic hepatitis C (1,980 immigrants and 18,479 non-immigrants) were reported between 1998-2007. Cases from 1991-1997 were excluded due to incomplete laboratory reporting during this period. Immigrant cases were older (mean age 47.1 vs. 43.1 years, p < 0.0001) and were less likely to be male (53.1% vs. 68.2%, p <0.0001). The overall rate of chronic hepatitis C was similar for immigrants and non-immigrants [rates/100,000 (95%CI) were 25.2 (24.1-26.4) vs. 27.8 (27.4-28.2), rate ratio= 0.91]. Immigrants from several world regions however had higher rates of chronic hepatitis C as compared to the non-immigrant population; Eastern Europe/Central Asia [77.6 (68.2-87.0) rate ratio = 2.8], Sub-Saharan Africa [60.2 (51.5-68.8), rate ratio = 2.2], South Asia [48.1 (41.5-54.7), rate ratio = 1.7]. Immigrants had a higher proportion of compensated cirrhosis (15.1% vs. 12.9%, p= 0.007) and hepatocellular carcinoma (1.2% vs. 0.6%, p= 0.005) compared to non-immigrantsConclusions: Immigrants from several world regions are at increased risk for chronic hepatitis C, have a higher proportion of hepatitis C related complications and are diagnosed a mean of > 8 years after arrival in Canada. Many immigrants would therefore benefit from early screening and appropriately timed treatment for chronic hepatitis C to decrease associated morbidity and mortality.
Introduction : Les immigrants ont un plus haut taux de mortalité causée par l'hépatite virale chronique et le carcinome hépatocellulaire comparativement aux individus nés au Canada. Approximativement 20% de ce fardeau serait dû au virus de l'hépatite C (VHC). En dépit de cette disparité, il n'existe aucun programme de dépistage du VHC chez les immigrants à leur arrivée au Canada. Ceci est en partie dû au manque de données basées sur des populations décrivant le fardeau du VHC chronique chez les immigrants. Méthodes : Afin de pourvoir à ce manque, nous avons créé une série de cas de tous les cas d'hépatite C chronique rapportés entre 1991-2008 au Québec en reliant la base de données MADO (Maladies à Déclaration Obligatoire du Québec) à cinq autres bases de données administratives québécoises; le MICC (immigrants arrivés au Québec), la RAMQ (assurance maladie provinciale du Québec et facturation des médecins) et les bases de données d'hospitalisation. Les taux rapportés ont été estimés en utilisant le nombre de cas rapportés chez les immigrants et les non immigrants durant la période d'étude. Les données de recensements de 1991, 1996, 2001 et 2006 (stratifiées en statut d'immigrant ou non immigrant) ont été utilisées comme dénominateur. Les taux d'incidences (TI), TI relatifs et les IC 95% ont été calculés avec la distribution de Poisson. La proportion de cas avec complications associées à l'hépatite C chronique a été calculée et comparée chez les immigrants et non immigrants. Résultats : Un total de 20 459 cas d'hépatite C chronique (1 980 immigrants et 18 479 non immigrants) ont été rapportés entre 1998-2007. Les cas datant de 1991 à 1997 ont été exclus dû au manque d'information complète de méthodes de laboratoire durant cette période. Les cas d'immigrants étaient plus âgés (âge moyen de 47.1 vs 43.1 années, p<0.0001) et moins probables chez les hommes (53.1% vs 68.2%, p <0.0001). Le TI d'hépatite C chronique était similaire entre immigrants et non immigrants [TI/100 000 (IC 95%) étaient de 25.1 (24.1-26.4) vs 27.8 (27.4-28.2), TI relatif = 0.91]. Les immigrants de plusieurs régions du monde, cependant, avaient un TI plus élevé d'hépatite C chronique comparativement aux non immigrants : l'Europe de l'Est/l'Asie centrale [77.6 (68.2-87.0), TI relatif = 1.7], l'Afrique subsaharienne [60.2 (51.5-68.8), TI relatif = 2.2], l'Asie du Sud [48.1 (41.5-54.7), TI relatif = 1.7]. Les immigrants avaient une proportion plus élevée de cirrhose compensée (15.1% vs 12.9%, p = 0.007) et de carcinome hépatocellulaire (1.2% vs 0.6%, p = 0.005) comparativement aux non immigrants. Conclusions : Les immigrants de plusieurs régions du monde sont à un risque plus élevé d'hépatite C chronique, ont une proportion plus élevée de complications liées à l'hépatite C et reçoivent un diagnostic en moyenne >8 ans après leur arrivée au Canada. Beaucoup d'immigrants bénéficieraient donc du dépistage et du traitement précoces pour l'hépatite C afin de diminuer la morbidité et la mortalité qui y sont associées.

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Burgert, Jens [Verfasser], and W. [Akademischer Betreuer] Seemann. "On direct and inverse problems related to longitudinal impact of non-uniform elastic rods / Jens Burgert ; Betreuer: W. Seemann." Karlsruhe : KIT-Bibliothek, 2020. http://d-nb.info/1223985881/34.

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Burgert, Jens [Verfasser], and W. [Akademischer Betreuer] Seemann. "On direct and inverse problems related to longitudinal impact of non-uniform elastic rods / Jens Burgert ; Betreuer: W. Seemann." Karlsruhe : KIT Scientific Publishing, 2021. http://d-nb.info/1233429345/34.

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