Assessment of the application of advanced technologies to subsonic CTOL transport aircraft

Design studies of the application of advanced technologies to future transport aircraft were conducted. These studies were reviewed from the perspective of an air carrier. A fundamental study of the elements of airplane operating cost was performed, and the advanced technologies were ranked in order of potential profit impact. Recommendations for future study areas are given

On the equivalence of Lambda(t) and gravitationally induced particle production cosmologies

The correspondence between cosmological models powered by a decaying vacuum energy density and gravitationally induced particle production is investigated. Although being physically different in the physics behind them we show that both classes of cosmologies under certain conditions can exhibit the same dynamic and thermodynamic behavior. Our method is applied to obtain three specific models that may be described either as Lambda(t)CDM or gravitationally induced particle creation cosmologies. In the point of view of particle production models, the later class of cosmologies can be interpreted as a kind of one-component unification of the dark sector. By using current type Ia supernovae data, recent estimates of the cosmic microwave background shift parameter and baryon acoustic oscillations measurements we also perform a statistical analysis to test the observational viability within the two equivalent classes of models and we obtain the best-fit of the free parameters. By adopting the Akaike information criterion we also determine the rank of the models considered here. Finally, the particle production cosmologies (and the associated decaying Lambda(t)-models) are modeled in the framework of field theory by a phenomenological scalar field model.Comment: 9 pages, 3 figures, new comments and 8 references added. Accepted for publication in Physics Letters

Global attractivity of the equilibrium of a nonlinear difference equation

summary:The authors consider the nonlinear difference equation $$x_{n+1}=\alpha x_n + x_{n-k}f(x_{n-k}), \quad n=0, 1,\dots .1 \text{where} \alpha \in (0, 1),\hspace{5.0pt}k \in \lbrace 0, 1, \dots \rbrace \hspace{5.0pt}\text{and}\hspace{5.0pt}f\in C^1[[0, \infty ),[0, \infty )] \qquad \mathrm{(0)}$$ with $f^{\prime }(x)<0$. They give sufficient conditions for the unique positive equilibrium of (0.1) to be a global attractor of all positive solutions. The results here are somewhat easier to apply than those of other authors. An application to a model of blood cell production is given

Statebuilding and narrative

In recent years, narrative approaches have become increasingly popular in the study of peaceand statebuilding. Yet, the conceptual and empirical idiosyncrasies of stories and storytelling are rarely acknowledged. This chapter provides an overview of the uses of narrative in the field to date. It highlights its value for understanding power imbalances, the complexity of human experiences and knowledge creation, and ethical challenges connected to fieldwork. Engaging in greater depth with conceptual and analytical perspectives on narrative, not least by drawing on insights from related social science disciplines, will help to uncover the unique contribution these perspectives can make to researching and practicing peace- and statebuilding.info:eu-repo/semantics/submittedVersio