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Structural health monitoring of sandwich beam and application of grid technologies
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Experimental validation of modal strain energies based damage identification method for a composite sandwich beam
No full textA vibration-based damage identification method, based on changes in modal strain energies before and after occurrence of damage, is presented for a composite sandwich beam. Experiments were performed to obtain the natural frequencies and mode shapes for validation of the presented method. The observed changes in modal strain energies were used for the prediction of existence and location of damage in a composite sandwich beam. Subsequently, these changes were also used to predict damage extents in the two stages. In the first stage, the proposed method is used to approximate the damage extents in the face and core. These were updated to obtain more accurate values of damage extent at the second stage by using the model updating theory. Experimental and numerical results were presented to demonstrate and verify the effectiveness of this method for several single and multiple damage cases. These damage cases also include interactive damage modes. Results indicate that the proposed method is capable of identifying the location and extent of damage in the faces and core of a composite sandwich beam
D-Penicillamine for preventing retinopathy of prematurity in preterm infants
Full text linkBackground The rate of retinopathy of prematurity (ROP) in moderately premature infants has decreased dramatically with improved care in the neonatal intensive care unit. A low rate of this disorder was unexpectedly observed among infants treated with intravenous D-penicillamine to prevent hyperbilirubinaemia. This observation led to the investigation of its use, both enterally as well as intravenously, to prevent ROP. Objectives To determine the effect of prophylactic administration of D-penicillamine on the incidence of acute ROP or severe ROP and other morbidities in preterm infants. Search methods We used the Cochrane Neonatal Review Group search strategy. Two review authors independently searched multiple electronic databases, previous reviews including cross references, abstracts, conference/symposia proceedings, and expert informants. We updated the search on November 27, 2012. Selection criteria We included randomised or quasi-randomised controlled trials if they administered D-penicillamine and compared it with no treatment or placebo to premature infants and reported on the outcome of ROP. Data collection and analysis We used the criteria and standard methods of the Cochrane Neonatal Review Group to assess the methodological quality of the included trials. One review author examined trials for validity. A second review author checked validity and they reached consensus on the final data before entry into this review. We used the standards of the Neonatal Cochrane Review Group to analyse data. Main results Three randomised trials met the inclusion criteria. The meta-analysis showed no significant differences in the risk of any stage ROP (typical risk ratio (RR) 0.32, 95% confidence interval (CI) 0.03 to 3.70), severe ROP (typical RR 0.38, 95% CI 0.03 to 4.26) or death (typical RR 0.95, 95% CI 0.68 to 1.32) in all treated infants. When the subgroup of infants under 1500 g birth weight was examined, the results were similar. No side effects were reported, and follow-up at one year revealed no significant differences in spasticity or developmental delay. Authors' conclusions Administration of prophylactic D-penicillamine in preterm infants does not prevent acute or severe ROP, death or neurodevelopmental delay. D-penicillamine cannot be recommended for the prevention of ROP based on the available evidence
Domain statistics in the relaxation of the one-dimensional Ising model with strong long-range interactions
Full text linkAfter a zero temperature quench, we study the kinetics of the one-dimensional
Ising model with long-range interactions between spins at distance decaying
as , with . As shown in our recent study [SciPost
Phys 10, 109 (2021)] that only a fraction of the non-equilibrium trajectories
is characterized by the presence of coarsening domains while in the remaining
ones the system is quickly driven towards a magnetised state. Restricting to
realisations displaying coarsening we compute numerically the probability
distribution of the size of the domains and find that it exhibits a scaling
behaviour with an unusual -dependent power-law decay. This peculiar
behaviour is also related to the divergence of the average size of domains with
system size at finite times. Such a scenario differs from the one observed when
, where the distribution decays exponentially. Finally, based on
numerical results and on analytical calculations we argue that the average
domain size grows asymptotically linearly in time.Comment: 10 page
Equilibrium structure and off-equilibrium kinetics of a magnet with tunable frustration
Full text linkWe study numerically a two-dimensional random-bond Ising model where frustration can be tuned by varying the fraction a of antiferromagnetic coupling constants. At low temperatures the model exhibits a phase with ferromagnetic order for sufficiently small values of a, aaa, an antiferromagnetic phase exists. After a deep quench from high temperatures, slow evolution is observed for any value of a. We show that different amounts of frustration, tuned by a, affect the dynamical properties in a highly nontrivial way. In particular, the kinetics is logarithmically slow in phases with ferromagnetic or antiferromagnetic order, whereas evolution is faster, i.e., algebraic, when spin-glass order is prevailing. An interpretation is given in terms of the different nature of phase space
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Suggested health services research action to achieve reduction of neonatal mortality in India
Full text linkDespite several national programs to reduce infant mortality, India had repeatedly failed to achieve its set targets for infant mortality. There are approximately one million neonatal deaths in India each year which accounts for nearly two-thirds of the infant deaths in India. India’s current trajectories of neonatal and infant mortality rates make it unlikely that it will achieve its targets for infant mortality rate for 2015 set under the Millennium Development Goals. Since two-thirds of infant deaths in India are neonatal deaths, implementation of effective neonatal care strategies would be essential to reduce infant mortality considerably. The history of child health services in India suggests an inattention to qualitative parameters, hindering a reversal of its failures. We discuss a format of mixed-methods participatory research, integrated with routine district level household surveys (DLHS), as a model of health services research which would better delineate the problems encountered in delivering effective newborn care at the primary care level
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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