Palatini inflation in models with an R2R^2 term

The Starobinsky model, considered in the framework of the Palatini formalism, in contrast to the metric formulation, does not provide us with a model for inflation, due to the absence of a propagating scalar degree of freedom that can play the role of the inflaton. In the present article we study the Palatini formulation of the Starobinsky model coupled, in general nonminimally, to scalar fields and analyze its inflationary behavior. We consider scalars, minimally or nonminimally coupled to the Starobinsky model, such as a quadratic model, the induced gravity model or the standard Higgs-like inflation model and analyze the corresponding modifications favorable to inflation. In addition we examine the case of a classically scale-invariant model driven by the Coleman-Weinberg mechanism. In the slow-roll approximation, we analyze the inflationary predictions of these models and compare them to the latest constraints from the Planck collaboration. In all cases, we find that the effect of the $R^2$ term is to lower the value of the tensor-to-scalar ratio.Comment: 22 pages, 8 figures, JCAP accepted versio

Rescuing Quartic and Natural Inflation in the Palatini Formalism

When considered in the Palatini formalism, the Starobinsky model does not provide us with a mechanism for inflation due to the absence of a propagating scalar degree of freedom. By (non)--minimally coupling scalar fields to the Starobinsky model in the Palatini formalism we can in principle describe the inflationary epoch. In this article, we focus on the minimally coupled quartic and natural inflation models. Both theories are excluded in their simplest realization since they predict values for the inflationary observables that are outside the limits set by the Planck data. However, with the addition of the $R^2$ term and the use of the Palatini formalism, we show that these models can be rendered viable.Comment: JCAP accepted version, 16 pages, 7 figure

Bayesian Analyses of the Burr Type ? Distribution under Doubly Type ?? censored samples using different Priors and Loss functions

The Bayesian analysis of the Burr type  distribution (Exponentiated Rayleigh) has been considered in the paper.  The Gamma, Exponential, Chi-Squared and Jeffrey prior have been assumed for posterior analysis. The estimation has been made under doubly type  censored samples. The Bayes estimation has been obtained under eight different loss functions (Squared error, Quadratic, Weighted, Linear exponential, Precautionary, Entropy, De Groot and non-Linear exponential loss functions). The simulation study has been conducted to compare by mean square error (MSE) for the performance of various estimators. Keyword: Bayesian Analyses, Exponentiated Rayleigh Distribution, Burr type  distribution, Loss function, Prior, Posterior, (Squared error, Quadratic, Weighted, Linear exponential, Precautionary, Entropy, De Groot and non-Linear exponential) loss functions

Domestic Politics and Conflict in the Cases of Israel, Palestine and Lebanon

When analysing conflicts from either academic or policy perspectives, conflict parties are often treated as monolithic 'black boxes'. Analysis tends to be centred on relations between principal parties and third party actors both in phases of conflict and of peace. In turn, attention is often focussed on the day to day evolution of relations between conflict parties, at the expense of the underlying long-term drivers of conflict and peace, which often lie within conflict parties themselves. This is particularly true in the Middle East, where the succession of crises in the region often leaves analysts and policy-makers little time to reflect upon the structural root drivers of conflict. Stemming from this premise, this report draws out some of the main structural, interestbased and ideational domestic drivers within three conflict parties in the Middle East: Israel, Palestine and Lebanon. On the basis of this analysis, this report examines the extent and manner in which these domestic drivers have impinged upon the ensuing inter-connected conflict hubs in the region; namely the conflict between Israel and the Palestinians, between Israel and Lebanon and Syria, and between Syria and Lebanon. This report also discusses how external parties and most importantly EU actors have affected these conflicts by operating – deliberately or not – on their respective domestic drivers. In turn, we conclude by drawing out alternative policy approaches that could aid the EU pursue its oft-quoted objective to contribute and promote peace in the region

Rock Slopes from Mechanics to Decision Making

http://lmrwww.epfl.ch/Eurock/Eurock2010/files/papers%20grouped.pdfRock slope instabilities are discussed in the context of decision making for risk assessment and management. Hence, the state of the slope and possible failure mechanism need to be defined first. This is done with geometrical and mechanical models for which recent developments are presented. This leads with appropriate consideration of uncertainties to risk determination and to the description of tools for risk management through active and passive countermeasures, including warning systems. The need for sensitivity analysis is then demonstrated, and final comments address updating through information collection.National Science Foundation (U.S.)MIT-Portugal ProgramPortuguese Science and Technology FoundationNorwegian Geotechnical Institute (International Centre for Geohazards)United States. Dept. of Energ

Buckling of stiffened curved panels under uniform axial compression

In bridge construction, the use of stiffened plates for box-girder or steel beams is common day to day practice. The advantages of the stiffening from the economical and mechanical points of view are unanimously recognized. For curved steel panels, however, applications are more recent and the literature on their mechanical behaviour including the influence of stiffeners is therefore limited. Their design with commercial finite element software is significantly time-consuming, which reduces the number of parameters which can be investigated in an optimization procedure. The present paper is thus dedicated to the study of the behaviour of stiffened curved panels under uniform longitudinal compression. It addresses the linear buckling and the ultimate strength which are both influenced by the coupled effects of curvature and stiffening. It finally proposes a design methodology based on that for stiffened flat plates adopted by European Standards and a column-like behaviour

Evolutionary framework with reinforcement learning-based mutation adaptation

Although several multi-operator and multi-method approaches for solving optimization problems have been proposed, their performances are not consistent for a wide range of optimization problems. Also, the task of ensuring the appropriate selection of algorithms and operators may be inefficient since their designs are undertaken mainly through trial and error. This research proposes an improved optimization framework that uses the benefits of multiple algorithms, namely, a multi-operator differential evolution algorithm and a co-variance matrix adaptation evolution strategy. In the former, reinforcement learning is used to automatically choose the best differential evolution operator. To judge the performance of the proposed framework, three benchmark sets of bound-constrained optimization problems (73 problems) with 10, 30 and 50 dimensions are solved. Further, the proposed algorithm has been tested by solving optimization problems with 100 dimensions taken from CEC2014 and CEC2017 benchmark problems. A real-world application data set has also been solved. Several experiments are designed to analyze the effects of different components of the proposed framework, with the best variant compared with a number of state-of-the-art algorithms. The experimental results show that the proposed algorithm is able to outperform all the others considered.</p