Development of unsteady aerodynamic analyses for turbomachinery aeroelastic and aeroacoustic applications

Theoretical analyses and computer codes are being developed for predicting compressible unsteady inviscid and viscous flows through blade rows. Such analyses are needed to determine the impact of unsteady flow phenomena on the structural durability and noise generation characteristics of turbomachinery blading. Emphasis is being placed on developing analyses based on asymptotic representations of unsteady flow phenomena. Thus, flow driven by small-amplitude unsteady excitations in which viscous effects are concentrated in thin layers are being considered. The resulting analyses should apply in many practical situations, lead to a better understanding of the relevent physics, and they will be efficient computationally, and therefore, appropriate for aeroelastic and aeroacoustic design applications. Under the present phase (Task 3), the effort was focused on providing inviscid and viscid prediction capabilities for subsonic unsteady cascade flows

Surveillance of Respiratory Hazards

journal articleBiomedical Informatic

Dens Evaginatus: A Problem-Based Approach

Dens evaginatus is an uncommon developmental anomaly of human dentition characterized by the presence of tubercle on the occlusal surface of mandibular premolars and lingual surface of anterior teeth. Due to occlusal trauma this tubercle tends to fracture thus exposing the pathway to the pulp chamber of teeth. This case report is about the presentation of dens evaginatus in mandibular premolars bilaterally; among them tooth 44 was associated with chronic apical periodontitis. Fractured tubercle of three premolars was sealed with composite resin. Root canal treatment was performed with tooth 44. Routine endodontic treatment did not result in remission of infection. Therefore, culture and sensitivity tests were performed to identify the cause and modify treatment plan accordingly. Triple antibiotic paste was used as an intracanal medicament to disinfect the root canal that resulted in remission of infection

Somewhere In The World : Dans Un Coin Du Monde

https://digitalcommons.library.umaine.edu/mmb-vp/5335/thumbnail.jp

Résultats et complications de la prise en charge interventionnelle des sténoses des artères pulmonaires

Introduction Quelles soient congénitales ou post-chirurgicales, les sténoses de l’artère pulmonaire font partie des pathologies qui, de nos jours, profitent le plus du traitement par cathétérisme cardiaque. L’évolution technique et l’expérience médicale acquises ces dernières années en font aujourd’hui une modalité thérapeutique primordiale, prouvée sûre et efficace. Néanmoins, il est toujours utile pour un centre universitaire qui pratique ces gestes de façon quotidienne de connaître l’efficacité de sa prise en charge et de pouvoir la comparer à la littérature correspondante. Méthode Nous présentons ici une étude rétrospective sur dix ans de la prise en charge interventionnelle des sténoses des artères pulmonaires dans le service de cardiologie pédiatrique du centre hospitalier universitaire vaudois (CHUV). Les données médicales et personnelles sont analysées afin d’effectuer une revue de la procédure et des résultats dans ce contexte pathologique. Puis les taux de réussite, respectivement de complications sont comparés par des moyens statistiques simples avec les données existantes. Résultats Entre 2006 et 2016, 55 patients (52.7% de garçons) ont été traités par cathétérisme cardiaque avec un total de 120 interventions pour des sténoses de l’artère pulmonaire. L’âge moyen au moment de l’intervention était de 5.21 ± 4.51 ans. Grâce aux cathétérisme cardiaque, la pression systolique en amont de la sténose baisse de 43.44 ± 19.13 mmHg à 35.84 ± 15.94 mmHg (p < 0.0001), la pression systolique en aval passe de 16.93 ± 6.13 mmHg à 19.91 ± 6.40 mmHg (p = 0.0003), le gradient de pression à la sténose évolue de 24.24 ± 17.12 mmHg à 18.45 ± 18.01 mmHg (p = 0.0093) et le diamètre de l’artère augmente de 4.55 ± 2.39 mm à 8.22 ± 2.49 mm (p < 0.0001). Aussi, en considérant la réussite du traitement par l’augmentation de >50% du diamètre initial, on obtient un taux global de 69.64%, qui en détail représente 58.67% dans le groupe « angioplastie » et 91.89% dans le groupe « stent » (p < 0.0001). Au niveau des complications, nous en avons dénombré 12 directement liées à la procédure (10%) dont quatre cas (3.33%) d’événements indésirables majeurs. Elles étaient significativement plus élevées dans le groupe « stent » avec 9 complications pour 3 dans l’angioplastie seule (p = 0.002). Conclusion Le cathétérisme cardiaque comme traitement des sténoses des artères pulmonaires est une technique sûre et efficace. Les taux de réussite obtenus dans notre études, que cela soit pour l’angioplastie seule ou pour la pose de stent, rejoignent ceux de la littérature correspondante. Au niveau des complications, la majorité est bégnine et n’impacte pas la santé du patient. Pour les cas plus sérieux, on ne note pas de morbidité ou de mortalité supérieure

THE STRUCTURE OF EMPLOYMENT AND UNEMPLOYMENT IN A DECLINING RURAL COMMUNITY

Labor and Human Capital,

An analysis for high Reynolds number inviscid/viscid interactions in cascades

An efficient steady analysis for predicting strong inviscid/viscid interaction phenomena such as viscous-layer separation, shock/boundary-layer interaction, and trailing-edge/near-wake interaction in turbomachinery blade passages is needed as part of a comprehensive analytical blade design prediction system. Such an analysis is described. It uses an inviscid/viscid interaction approach, in which the flow in the outer inviscid region is assumed to be potential, and that in the inner or viscous-layer region is governed by Prandtl's equations. The inviscid solution is determined using an implicit, least-squares, finite-difference approximation, the viscous-layer solution using an inverse, finite-difference, space-marching method which is applied along the blade surfaces and wake streamlines. The inviscid and viscid solutions are coupled using a semi-inverse global iteration procedure, which permits the prediction of boundary-layer separation and other strong-interaction phenomena. Results are presented for three cascades, with a range of inlet flow conditions considered for one of them, including conditions leading to large-scale flow separations. Comparisons with Navier-Stokes solutions and experimental data are also given

Unsteady Aerodynamic Models for Turbomachinery Aeroelastic and Aeroacoustic Applications

Theoretical analyses and computer codes are being developed for predicting compressible unsteady inviscid and viscous flows through blade rows of axial-flow turbomachines. Such analyses are needed to determine the impact of unsteady flow phenomena on the structural durability and noise generation characteristics of the blading. The emphasis has been placed on developing analyses based on asymptotic representations of unsteady flow phenomena. Thus, high Reynolds number flows driven by small amplitude unsteady excitations have been considered. The resulting analyses should apply in many practical situations and lead to a better understanding of the relevant flow physics. In addition, they will be efficient computationally, and therefore, appropriate for use in aeroelastic and aeroacoustic design studies. Under the present effort, inviscid interaction and linearized inviscid unsteady flow models have been formulated, and inviscid and viscid prediction capabilities for subsonic steady and unsteady cascade flows have been developed. In this report, we describe the linearized inviscid unsteady analysis, LINFLO, the steady inviscid/viscid interaction analysis, SFLOW-IVI, and the unsteady viscous layer analysis, UNSVIS. These analyses are demonstrated via application to unsteady flows through compressor and turbine cascades that are excited by prescribed vortical and acoustic excitations and by prescribed blade vibrations. Recommendations are also given for the future research needed for extending and improving the foregoing asymptotic analyses, and to meet the goal of providing efficient inviscid/viscid interaction capabilities for subsonic and transonic unsteady cascade flows

Content & Watkins's account of natural axiomatizations

This paper briefly recounts the importance of the notion of natural axiomatizations for explicating hypothetico-deductivism, empirical significance, theoretical reduction, and organic fertility. Problems for the account of natural axiomatizations developed by John Watkins in Science and Scepticism and the revised account developed by Elie Zahar are demonstrated. It is then shown that Watkins's account can be salvaged from various counter-examples in a principled way by adding the demand that every axiom of a natural axiomatization should be part of the content of the theory being axiomatized. The crucial point here is that content cannot simply be identified with the set of logical consequences of a theory, but must be restricted to a proper subset of the consequence set. It is concluded that the revised Watkins account has certain advantages over the account of natural axiomatizations offered in Gemes (1993)

1865-03-30 J.M. Ayer seeks information on whereabouts of William Sylvester of Company G

https://digitalmaine.com/cw_me_4th_regiment_corr/1544/thumbnail.jp