405 research outputs found
Non-uniqueness for the nonlocal Liouville equation in and applications
We construct multiple solutions to the nonlocal Liouville equation
\begin{equation} \label{eqk} \tag{L} (-\Delta)^{\frac{1}{2}} u = K(x) e^u \quad
\mbox{ in } \mathbb{R}. \end{equation} More precisely, for of the form
with small and for some , we prove existence of multiple solutions to \eqref{eqk} bifurcating from
the bubbles. These solutions provide examples of flat metrics in the half-plane
with prescribed geodesic curvature on its boundary. Furthermore, they
imply the existence of multiple ground state soliton solutions for the
Calogero-Moser derivative NLS
Sign-changing tower of bubbles for a sinh-Poisson equation with asymmetric exponents
Motivated by the statistical mechanics description of stationary
2D-turbulence, for a sinh-Poisson type equation with asymmetric nonlinearity,
we construct a concentrating solution sequence in the form of a tower of
singular Liouville bubbles, each of which has a different degeneracy exponent.
The asymmetry parameter corresponds to the ratio between the
intensity of the negatively rotating vortices and the intensity of the
positively rotating vortices. Our solutions correspond to a superposition of
highly concentrated vortex configurations of alternating orientation; they
extend in a nontrivial way some known results for . Thus, by
analyzing the case we emphasize specific properties of the
physically relevant parameter in the vortex concentration phenomena
Mediterranean Forecasting System: forecast and analysis assessment through skill scores
Abstract. This paper describes the first evaluation of the quality of the forecast and analyses produced at the basin scale by the Mediterranean ocean Forecasting System (MFS) (http://gnoo.bo.ingv.it/mfs). The system produces short-term ocean forecasts for the following ten days. Analyses are produced weekly using a daily assimilation cycle. The analyses are compared with independent data from buoys, where available, and with the assimilated data before the data are inserted. In this work we have considered 53 ten days forecasts produced from 16 August 2005 to 15 August 2006. The forecast skill is evaluated by means of root mean square error (rmse) differences, bias and anomaly correlations at different depths for temperature and salinity, computing differences between forecast and analysis, analysis and persistence and forecast and persistence. The Skill Score (SS) is defined as the ratio of the rmse of the difference between analysis and forecast and the rmse of the difference between analysis and persistence. The SS shows that at 5 and 30 m the forecast is always better than the persistence, but at 300 m it can be worse than persistence for the first days of the forecast. This result may be related to flow adjustments introduced by the data assimilation scheme. The monthly variability of SS shows that when the system variability is high, the values of SS are higher, therefore the forecast has higher skill than persistence. We give evidence that the error growth in the surface layers is controlled by the atmospheric forcing inaccuracies, while at depth the forecast error can be interpreted as due to the data insertion procedure. The data, both in situ and satellite, are not homogeneously distributed in the basin; therefore, the quality of the analyses may be different in different areas of the basin
Mediterranean Forecasting System: forecast and analysis assessment through skill scores
This paper describes the first evaluation of the
quality of the forecast and analyses produced at the basin
scale by the Mediterranean ocean Forecasting System (MFS)
(http://gnoo.bo.ingv.it/mfs). The system produces short-term
ocean forecasts for the following ten days. Analyses are produced
weekly using a daily assimilation cycle. The analyses
are compared with independent data from buoys, where
available, and with the assimilated data before the data are
inserted. In this work we have considered 53 ten days forecasts
produced from 16 August 2005 to 15 August 2006.
The forecast skill is evaluated by means of root mean
square error (rmse) differences, bias and anomaly correlations
at different depths for temperature and salinity, computing
differences between forecast and analysis, analysis
and persistence and forecast and persistence. The Skill Score
(SS) is defined as the ratio of the rmse of the difference between
analysis and forecast and the rmse of the difference
between analysis and persistence. The SS shows that at 5 and
30m the forecast is always better than the persistence, but at
300m it can be worse than persistence for the first days of
the forecast. This result may be related to flow adjustments
introduced by the data assimilation scheme. The monthly
variability of SS shows that when the system variability is
high, the values of SS are higher, therefore the forecast has
higher skill than persistence.
We give evidence that the error growth in the surface layers
is controlled by the atmospheric forcing inaccuracies, while at depth the forecast error can be interpreted as due to the
data insertion procedure. The data, both in situ and satellite,
are not homogeneously distributed in the basin; therefore, the
quality of the analyses may be different in different areas of
the basin
The Ljapunov-Schmidt reduction for some critical problems
This is a survey about the application of the Ljapunov-Schmidt reduction for
some critical problems
Is There a Relationship between Laser Therapy and Root Canal Cracks Formation? A Systematic Review
Introduction: Crack formation has become an important issue for endodontists, as it can be decisive for the long-term prognosis of the endodontically treated tooth. Since the applicability of laser in endodontics has become frequent, this systematic review aimed to evaluate the association between laser therapy and the formation of cracks in the dentinal structure of the root canal. Materials and Methods: A search was performed in PubMed, Scopus, Web of Science, and Virtual Health Library, as well as in the gray literature, on September 24, 2021. Studies that evaluated the formation of cracks in human root dentin due to different types of lasers were included. The risk of bias was assessed following the modified version of the Consolidated Standards of Reporting Trials (CONSORT) checklist tool. A meta-analysis was performed to evaluate (i) the total number of crack incidences; (ii) complete crack formation; (iii) incomplete crack formation; (iv) intra-dentinal crack formation between ultrasonic tips and laser use. The mean difference was calculated with a 95% confidence interval in a fixed-effect model, the heterogeneity was tested using the I2 index with level of significance of 5%. Results: Of the 22 studies included in this review, 15 have shown that lasers can form cracks in root dentin, including those that performed baseline assessment of samples. The meta-analysis confirmed no difference in crack formation between ultrasonic tips and laser devices. Conclusions: Laser therapy has been gaining prominence in endodontics and that irradiation can form and propagate cracks in the dentinal structure of the root canal assessed by in vitro studies. This is a critical concern for endodontists as it affects the strength and longevity of the tooth. Future research is encouraged to seek the standardization of good methodological practices and achieve establishing parameters to minimize harmful effects of laser on dentin
Responsibility Analysis by Abstract Interpretation
Given a behavior of interest in the program, statically determining the
corresponding responsible entity is a task of critical importance, especially
in program security. Classical static analysis techniques (e.g. dependency
analysis, taint analysis, slicing, etc.) assist programmers in narrowing down
the scope of responsibility, but none of them can explicitly identify the
responsible entity. Meanwhile, the causality analysis is generally not
pertinent for analyzing programs, and the structural equations model (SEM) of
actual causality misses some information inherent in programs, making its
analysis on programs imprecise. In this paper, a novel definition of
responsibility based on the abstraction of event trace semantics is proposed,
which can be applied in program security and other scientific fields. Briefly
speaking, an entity ER is responsible for behavior B, if and only if ER is free
to choose its input value, and such a choice is the first one that ensures the
occurrence of B in the forthcoming execution. Compared to current analysis
methods, the responsibility analysis is more precise. In addition, our
definition of responsibility takes into account the cognizance of the observer,
which, to the best of our knowledge, is a new innovative idea in program
analysis.Comment: This is the extended version (33 pages) of a paper to be appeared in
the Static Analysis Symposium (SAS) 201
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