<p>Global mean surface air temperature (GMST) is one of the most well-known and robust measures of global climate change both contemporarily as well as through deep time. In contemporary climate science, the most often discussed causes of GMST change are referred to as external radiative forcings, which are considered to be exogenous to the land-atmosphere-ocean system and which impose a radiative energy imbalance (N) at the top of the earth’s atmosphere. Examples of external radiative forcings include changes in well-mixed greenhouse gas concentrations, changes in volcanic or anthropogenic aerosol loading, anthropogenic changes in land use, and changes in incoming solar radiation. The climate system can also produce unforced variability in GMST that spontaneously emerges from the internal dynamics of the land-atmosphere-ocean system. Unforced GMST variability can emerge via a vertical redistribution of heat within the climate system. For example, there can be a net transport of energy from below the ocean’s mixed layer to the surface during an El-Niño event. Additionally, unforced GMST variability can be due to an unforced change in N. For example, an internally generated change in the strength of an ocean circulation could alter the extent of sea ice and thus change the Earth’s albedo.</p><p>Understanding the magnitude and mechanisms underlying unforced GMST variability is relevant for both the attribution of past climate change to various causes, as well to the prediction of future changes on policy-relevant timescales. However, the literature on unforced GMST variability, particularly at interdecadal and longer timescales, is inconsistent and there is significant disagreement on its magnitude, on its primary geographic origins, and on the physical mechanisms that are most responsible.</p><p>This dissertation seeks to advance the scientific understanding of unforced GMST variability by addressing seven primary scientific goals: 1) To identify the geographic locations (and by proxy modes of variability) that are most responsible for unforced GMST variability in both the instrumental record and in climate models. 2) To identify the primary reasons why AOGCMs disagree on the magnitude of interdecadal unforced GMST variability. 3) To quantify the magnitude of unforced GMST variability in observations over the instrumental record as well as in multi-proxy reconstructions over the past millennium. 4) To quantify the degree to which unforced GMST variability is influenced by internally generated N energy imbalances. 5) To understand how anomalous N fluxes can influence large scale modes of surface temperature variability that affect GMST, such as the Atlantic Multidecadal Oscillation (AMO). 6) To understand the nature of the restoring force responsible for returning a perturbed GMST anomaly back to equilibrium; and 7) To understand how the magnitude and mechanisms of GMST variability might change in the future as the climate warms. </p><p>This research relies on the analysis of coupled Atmosphere-Ocean general circulation models (AOGCMs) that participated in Phase 5 of the Coupled Model Intercomparison Project (CMIP5), satellite observations of the Earth’s energy budget from the Clouds and Earth’s Radiant Energy System (CERES), instrumental surface temperature observations from NASA GISS Surface Temperature Analysis (GISTEMP), atmospheric reanalysis data from the European Center for Medium-Range Weather Forecasts interim reanalysis (ERA-I) and surface temperature reconstructions over the past millennium from numerous multiproxy archives.</p><p>This work has yielded six primary conclusions: I) Dynamics over the tropical Pacific Ocean represent the primary contributor to unforced GMST variability at interdecadal and longer timescales with lesser contributions from dynamics in the subpolar north Atlantic and Southern Ocean. II) AOGCMs tend to underestimate the magnitude of unforced GMST variability at interdecadal and longer timescales relative to both instrumental and reconstructed surface temperature datasets. III) N imbalances can act to significantly enhance interdecadal GMST variability. IV) GMST is able to restore equilibrium after an internally generated perturbation via the transport of energy to high-latitude locations and via the rearrangement the atmospheric circulation; both of which allow for much more efficient release of outgoing longwave radiation (OLR) than would otherwise be expected. V) N imbalances can significantly enhance internal modes of variability such as the AMO; and VI) The magnitude of interdecadal GMST variability is likely to decline and the generating mechanisms of such variability may be fundamentally altered as climate warms over the 21st century. These results advance our understanding of unforced GMST variability and they have implications for attribution studies and may inform projections of climate change on interdecadal timescales.</p> / Dissertation

Now a days the conditions at which the image taken may lead to near zero visibility for the human eye. They may usually due to lack of clarity, just like effects enclosed on earth’s atmosphere which have effects upon the images due to haze, fog and other day light effects. The effects on such images may exists, so useful information taken under those scenarios should be enhanced and made clear to recognize the objects and other useful information. To deal with such issues caused by low light or through the imaging devices experience haze effect many image processing algorithms were implemented. These algorithms also provide nonlinear contrast enhancement to some extent. We took pre-existed algorithms like SMQT (Successive mean Quantization Transform), V Transform, histogram equalization algorithms to improve the visual quality of digital picture with large range scenes and with irregular lighting conditions. These algorithms were performed in two different method and tested using different image facing low light and color change and succeeded in obtaining the enhanced image. These algorithms helps in various enhancements like color, contrast and very accurate results of images with low light. Histogram equalization technique is implemented by interpreting histogram of image as probability density function. To an image cumulative distribution function is applied so that accumulated histogram values are obtained. Then the values of the pixels are changed based on their probability and spread over the histogram. From these algorithms we choose histogram equalization, MATLAB code is taken as reference and made changes to implement in API (Application Program Interface) using JAVA and confirms that the application works properly with reduction of execution time.

Membrane proteins perform a variety of functions essential for the viability of the cell, including transport and signalling across the membrane. Most membrane proteins are formed from bundles of transmembrane helices. In this thesis molecular dynamics simulations have been used to investigate helix insertion into bilayers and helix association within bilayers. The potentials of mean force for the insertion of helices derived from the cystic fibrosis transmembrane conductance regulator into lipid bilayers were calculated using coarse-grained molecular dynamics simulations. The results showed that the insertion free energy increased with helix length and bilayer hydrophobic width. The insertion free energies obtained were significantly larger than comparable quantities obtained from translocon- mediated insertion experiments, consistent with a variety of previous studies. The implications of this observation for the interpretation of in vivo translocon-mediated insertion experiments, and the function of the translocon, are discussed. Coarse-grained and atomistic molecular dynamics simulations of the transmembrane region of the receptor tyrosine kinase EphA1 suggested that the transmembrane helix dimer was most stable when interacting via the glycine zipper motif, in agreement with a structure obtained by NMR spectroscopy. Coarse-grained simulations of the transmembrane region of EphA2 suggested that the dimer has two stable orientations, interacting via a glycine zipper or a heptad motif. Both structures showed right-handed dimers, although an NMR structure of the transmembrane region of EphA2 shows a left-handed dimer interacting via the heptad motif. Both structures obtained from coarse-grained simulations proved unstable when simulated at an atomistic level of detail. The potentials of mean force for dissociating the EphA1 and EphA2 dimers were calcu- lated using coarse-grained molecular dynamics calculations. Convergence of the detailed structure of the profiles was not conclusively shown, although association free energies cal- culated from the profiles were consistent over a variety of simulation times. The association free energies were slightly larger than experimental values obtained for comparable sys- tems, but consistent with similar computational calculations previously reported. However, direct comparisons are difficult owing to the influence of environmental factors on reported association free energies. The potential of mean force profiles showed that the interaction via the glycine zipper motif for EphA1 was significantly more stable than any other confor- mation. For EphA2 the potential of mean force profiles suggested that interaction via the glycine zipper and heptad motifs both provided stable or metastable conformations, with the interaction via the glycine zipper motif probably at least as stable as that via the heptad motif.

In this work we study two problems about parabolic partial differential equations on Riemannian manifolds with conical singularities. The first problem we are concerned with is the existence and regularity of solutions to the Cauchy problem for the inhomogeneous heat equation on compact Riemannian manifolds with conical singularities. By introducing so called weighted Hölder and Sobolev spaces with discrete asymptotics, we provide a complete existence and regularity theory for the inhomogeneous heat equation on compact Riemannian manifolds with conical singularities. The second problem we study is the short time existence problem for the generalized Lagrangian mean curvature flow in almost Calabi-Yau manifolds, when the initial Lagrangian submanifold has isolated conical singularities that are modelled on stable special Lagrangian cones. First we use Lagrangian neighbourhood theorems for Lagrangian submanifolds with conical singularities to integrate the generalized Lagrangian mean curvature flow to a nonlinear parabolic equation of functions, and then, using the existence and regularity theory for the heat equation, we prove short time existence of the generalized Lagrangian mean curvature flow with isolated conical singularities by letting the conical singularities move around in the ambient space and the model cones to rotate by unitary transformations.

Medical cost analysis is an important part of treatment evaluation. Since resources are limited in society, it is important new treatments are developed with proper costconsiderations. The mean has been mostly accepted as a measure of the medical cost analysis. However, it is well known that cost data is highly skewed and the mean could be highly influenced by outliers. Therefore, in many situations the mean cost alone cannot offer complete information about medical costs. The quantiles (e.g., the first quartile, median and third quartile) of medical costs could better represent the typical costs paid by a group of individuals, and could provide additional information beyond mean cost. For a specified patient population, cost estimates are generally determined from the beginning of treatments until death or end of the study period. A number of statistical methods have been proposed to estimate medical cost. Since medical cost data are skewed to the right, normal approximation based confidence intervals can have much lower coverage probability than the desired nominal level when the cost data are moderately or severely skewed. Additionally, we note that the variance estimators of the cost estimates are analytically complicated. In order to address some of the above issues, in the first part of the dissertation we propose two empirical likelihood-based confidence intervals for the mean medical costs: One is an empirical likelihood interval (ELI) based on influence function, the other is a jackknife empirical likelihood (JEL) based interval. We prove that under very general conditions, −2log (empirical likelihood ratio) has an asymptotic standard chi squared distribution with one degree of freedom for mean medical cost. Also we show that the log-jackknife empirical likelihood ratio statistics follow standard χ2 distribution with one degree of freedom for mean medical cost. In the second part of the dissertation, we propose an influence function-based empirical likelihood method to construct a confidence region for the vector of regression parameters in mean cost regression models with censored data. The proposed confidence region can be used to obtain a confidence interval for the expected total cost of a patient with given covariates. The new method has sound asymptotic property (Wilks Theorem). In the third part of the dissertation we propose empirical likelihood method based on influence function to construct confidence intervals for quantile medical costs with censored data. We prove that under very general conditions, −2log (empirical likelihood ratio) has an asymptotic standard chi squared distribution with one degree of freedom for quantile medical cost. Simulation studies are conducted to compare coverage probabilities and interval lengths of the proposed confidence intervals with the existing confidence intervals. The proposed methods are observed to have better finite sample performances than existing methods. The new methods are also illustrated through a real example.

This thesis is based on three empirical essays in financial development and economic growth. The first essay, investigated in the third chapter, the effect of financial development on economic growth in the context of Saudi Arabia, an oil-rich economy. In doing so, the study distinguishes between the effects of financial development on the oil and non-oil sectors of the economy. The Autoregressive Distributed Lag (ARDL) bounds test methodology is applied to yearly data over the period 1968 to 2010. The finding of this study is that financial development has a positive impact on the growth of the non-oil sector. In contrast, its impact on the oil-sector growth and total GDP growth is either negative or insignificant. This suggests that the relationship between financial development and growth may be fundamentally different in resource-dominated economies. The second essay revisited, in the fourth chapter, the relationship between financial development and economic growth in a panel of 52 middle-income countries over the 1980-2008 period. Using pooled mean group estimations in a dynamic heterogeneous panel setting, we show that there is an inverted U-shaped relationship between finance and growth in the long-run. In the short run, the relationship is insignificant. This suggests that too much finance can exert a negative influence on growth in middle-income countries. The finding of a non-monotonic effect of financial development on growth is confirmed by estimating a dynamic panel threshold model. The third essay empirically explores cross-country evidence of the effects of financial development shocks on economic growth. It employs a Global Vector Autoregressive (GVAR) model, which allows us to capture the dynamics of this relationship in a multi-country setting, and connects countries through bilateral international trade. Given the progressive role that Brazil, Russia, India, China and South Africa (BRICS) play in the world economic arena, this essay focuses on whether financial development in one BRICS member state affects economic growth in the other BRICS. To this end, the study finds empirical evidence that credit to the private sector has a positive spillover effect on growth in some of the BRICS countries. However, the results imply that the current level of financial integration among the BRICS countries is still not mature enough to spur economic growth for all the BRICS members.

Introduction: It has been proposed that inadequate rest intervals may contribute to decreased performance of activities. However, previous research has not investigated the effect of rest interval on performance of the Star Excursion Balance Test (SEBT) in individuals with and without chronic ankle instability. Objective: To determine whether rest interval affects performance of the SEBT associated with chronic ankle instability (CAI) and whether neuromuscular function, postural control or biomechanics can be associated factors which may help discriminate between healthy individuals and those with CAI during the SEBT. Design: 2-group counterbalanced study. Participants: Participants included 24 individuals with a history of at least one ankle sprain in the past year and at least 2 episodes of giving way in the past 6 month prior to study enrollment, and 24 individuals with no history of ankle sprain or instability in their lifetime. Methods: Subjects completed 3 trials in each of the 3 reach directions (anteromedial, medial, posteromedial) in random order. A total of three visits were required in order to complete the 3 rest intervals (10, 20, 40 seconds). Normalized maximum reach distance, electromyographic (EMG) activation of tibialis anterior, peroneus longus, and medial gastrocnemius muscles, multiplanar motion of the lower extremity, coupling angles (CA) of lower extremity segments and maximum lateral center of pressure velocity were calculated and compared between groups in each direction for each rest interval. Results: Rest interval did not influence differences of reach distance, EMG ankle muscle activation, kinematics and center of pressure velocity between healthy individuals and those with CAI during the SEBT. However, the rest interval of 20 seconds demonstrated differences in CAs of tibial internal rotation/dorsiflexion (TIR/DF) and tibial internal rotation/eversion (TIR/EV) between healthy individuals and those with CAI during the SEBT. Overall, reach distance, mean amplitude of EMG ankle muscles, kinematics and joint CAs were different between healthy individuals and those with CAI during the SEBT regardless of rest interval. Discussion: Based on these results, differences exist in neuromuscular functions and biomechanics between healthy individuals and those with CAI when performing the SEBT. A rest interval time of 20 seconds between trials during the SEBT is an appropriate time to discriminate joint CAs of TIR/DF and TIR/EV between healthy individuals and those with CAI during the SEBT. These findings have implications for treatment and possible prevention of CAI.

The purpose of this thesis is to further develop numerical methods for solving surface problems by utilizing tangential calculus and the trace finite element method. Direct computation on the surface is possible by the use of tangential calculus, in contrast to the classical approach of mapping 2D parametric surfaces to 3D surfaces by means of differential geometry operators. Using tangential calculus, the problem formulation is only dependent on the position and normal vectors of the 3D surface. Tangential calculus thus enables a clean, simple and inexpensive formulation and implementation of finite element methods for surface problems. Meshing techniques are greatly simplified from the end-user perspective by utilizing an unfitted finite element method called the Trace Finite Element Method, in which the basic idea is to embed the surface in a higher dimensional mesh and use the shape functions of this background mesh for the discretization of the partial differential equation. This method makes it possible to model surfaces implicitly and solve surface problems without the need for expensive meshing/re-meshing techniques especially for moving surfaces or surfaces embedded in 3D solids, so called embedded interface problems. Using these two approaches, numerical methods for solving three surface problems are proposed: 1) minimal surface problems, in which the form that minimizes the mean curvature was computed by iterative update of a level-set function discretized using TraceFEM and driven by advection, for which the velocity field was given by the mean curvature flow, 2) elastic membrane problems discretized using linear and higher order TraceFEM, which makes it straightforward to embed complex geometries of membrane models into an elastic bulk for reinforcement and 3) stabilized, accurate vertex normal and mean curvature estimation with local refinement on triangulated surfaces. In this thesis the basics of the two main approaches are presented, some aspects such as stabilization and surface reconstruction are further developed, evaluated and numerically analyzed, details on implementations are provided and the current state of work is presented.

Title: Some possibilities of heteroskedasticity modeling with applications to non-life insurance Author:Petra Pavlačková Department: Department of Probability and Mathematical Statistics Supervisor: Ing. Zimmermann Pavel, Ph.d. Abstract: This thesis deals with the possibilities of modeling heteroskedasticity using generalized linear models. It summarizes the assumption for these models and their application in practice. It shows the practical need for these models. Furthermore, the thesis deals with the modeling of variance using other methods than generalized lienar models - such as generalized additive models or local regression. Comparison of methods is graphically demonstrated. Keywords: Dispersion parameter, variance function, Joint modelling of mean and dispersion

1 Assesment of land use influence on landscape naturalness Abstract Human activities are putting an increasing pressure on natural areas. Complex understanding and evaluation of human impact on the environment is considered to be a key tool to preserve natural balance. Biodiversity was chosen as proxy for naturalness as it has been recognized as one of the main components of environmental stability. Several different indices has been developed to assess human-induced changes in biodiversity. In this study, mean abundance of original species relative to their abundance in undisturbed ecosystems (MSA) is used as an indicator for current state of naturalness. Indicator MSA is built on simple cause-effect relationships between environmental drivers and biodiversity impacts, based on state-of-the-art knowledge. Drivers considered are landcover change, land-use intensity, fragmentation and infrastructure development. As most of biodiversity indices, MSA illustrate prevailingly poor condition of nature as a result of human induced pressures, especially land cover change. Considering constantly increasing population and economic development human pressure grow is likely to continue during the coming decades with irreversible loss in the diversity of life on the Earth. Keywords: Mean species abundance (MSA) - land...