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1.
ABSTRACT

The interest in automatic modal parameter extraction techniques has increased significantly in recent years because of the rising demand for Continuous Structural Health Monitoring (CSHM) of civil structures and infrastructures. The wider use of CSHM is related to its capability for early damage detection and therefore to its usefulness for planning maintenance and strengthening interventions. This article presents the main steps followed in creating a robust routine to run on an online basis the first-ever Continuous Vibration-Based Structural Health Monitoring (CVB-SHM) of a large masonry oval dome, i.e., the dome of the Regina Montis Regalis Basilica, also known as Sanctuary of Vicoforte. The procedure uses an output-only stochastic subspace identification method complemented by an automatic analysis applied to identification results, which are typically provided in terms of stabilization diagrams. In this study, the fully automatic procedure also includes a hierarchical clustering algorithm to separate authentic from spurious modes.  相似文献   
2.
Yeha, in Tigray, is the most impressive site with evidence for South Arabian influence dating to the first millennium BC in the northern Horn of Africa (Eritrea and northern Ethiopia). The evidence from this site was used to identify a ‘Pre-Aksumite’ or ‘Ethiopian-Sabean’ Period (mid-first millennium BC) when an early Afro-Arabian state apparently arose in the region. A ‘Pre-Aksumite Culture’, characterised by South Arabian elements, was also suggested as a distinctive archaeological culture in northern Ethiopia and Eritrea. However, recent fieldwork in these countries suggests that a Pre-Aksumite culture actually did not exist and South Arabian features were restricted to a few sites, which were scattered in a mosaic of different archaeological cultures in the first millennium BC. This hypothesis is tested through a comparison between the ceramics from Yeha and those from Matara and other sites of the first millennium BC in Tigray and Eritrea.  相似文献   
3.
Paulina-Carabajal, A. & Coria, R.A. 15.4.2015. An unusual theropod frontal from the Upper Cretaceous of north Patagonia. Alcheringa 39, 514–518. ISSN 0311-5518

We report an isolated left frontal (MCF-PVPH 320) corresponding to a medium-sized theropod dinosaur from the Portezuelo Formation (Coniacian) of northern Patagonia. It shows a unique combination of traits that are not present in any other known Cretaceous theropod from South America. MCF-PVPH 320 is robust and anteroposteriorly short, with a flat and smooth dorsal surface largely excavated by the supratemporal fossa. Endocranially, the olfactory bulb impression is elongate, and the olfactory tract impression is markedly shortened anteroposteriorly. MCF-PVPH 320 differs greatly from the frontals of Late Cretaceous theropods, such as abelisaurids, megaraptorines and carcharodontosaurids. In contrast, character states including the thickness of the bone, V-shaped frontoparietal suture, reduced participation on the orbital margin and markedly short olfactory tract impression suggest the presence of an unknown mid-sized to large allosauroid for the Portezuelo Formation.

Ariana Paulina-Carabajal [], CONICET-Museo Carmen Funes, Av. Córdoba 55 (8318), Plaza Huincul, Neuquén, Argentina; Rodolfo A. Coria [], CONICET-Instituto de Paleobiología y Geología, Universidad Nacional de Río Negro. Av. Roca 1242 (8332), Gral. Roca, Río Negro, Argentina.  相似文献   
4.
This paper outlines the environmental history of the Tigrean Plateau (northern Ethiopia) during the Holocene, based on the available geomorphological, palynological, archaeological, and historical evidence. At present, it seems that (1) the plateau experienced a more humid climate with a denser vegetation cover during the Early Holocene; (2) Soil erosion due to clearing vegetation began in the Middle Holocene; (3) agricultural activity was intensified in the Late Holocene, as a consequence of the rise of a state; (4) demographic pressure increased from the early first millennium BC to the mid–first millennium AD, causing soil erosion; (5) environmental degradation and demographic decline occurred in the late first millennium AD; (6) the vegetation cover was regenerated in the early second millennium AD; and (7) progressive vegetation clearance started again in the second half of the second millennium AD.Cet article trace l'histoire ambiante du Plateau Tigréen dans l'Holocène en utilisant les données géomorphologiques, palynologiques, archéologiques et historiques. Il semble que (1) dans l'Holocène ancien le plateau était caractérisé par une phase humide avec une dense végétation; (2) l'érosion causée par l'abbattage de la végétation commen¸a dans l'Holocène moyen; (3) l'activité agricole s'inténsifia à la fin de l'Holocène, par conséquence de l'essor d'un état; (4) la pression démographique augmenta de plus en plus du début du premier millénaire av. J.-Ch. à la moitié du premier millénaire ap. J.-Ch.; (5) la dégradation ambiante et la diminution démographique se vérifièrent à la fin du premier millénaire ap. J.-Ch.; (6) une régéneration de la vegetation se vérifia au début du seconde millénaire ap. J.-Ch.; et (7) l'abbatage de la végétation recommen¸a dans la seconde moitié du seconde millénaire ap. J.-Ch.  相似文献   
5.
O’Gorman, J.P. & Coria, R.A. September 2016. A new elasmosaurid specimen from the upper Maastrichtian of Antarctica: new evidence of a monophyletic group of Weddellian elasmosaurids. Alcheringa 41, xxx–xxx. ISSN 0311-5518

A new fossil elasmosaurid specimen, MLP 15-I-7-48, from the upper Maastrichtian Sandwich Bluff Member of the López de Bertodano Formation, Vega Island, Archipelago James Ross, Antarctica, is described. The fossil is a well-preserved anterior limb, which shares with Vegasaurus molyi from the upper Maastrichtian of Antarctica, a concave to flat anterior margin of the humeral shaft, and with Vegasaurus molyi and Aphrosaurus furlongi from the upper Maastrichtian of California, a well-defined depression on the anterior margin of the ventral surface of the humeral shaft. A phylogenetic analysis recovered MLP 15-I-7–48 as sister group of the lower Maastrichtian Vegasaurus molyi within a new clade nominated as Weddellonectia: Kawanectes lafquenianum ((Vegasaurus molyi; MLP 15-I-7–48) (Morenosaurus stocki (Aristonectinae))). This indicates that the previously proposed faunal turnover between the early and late Maastrichtian Weddellian marine reptile fauna, did not severely affect the non-aristonectine elasmosaurids. Additionally, other taxa previously considered evidence of a faunal turnover are re-evaluated.

José P. O’Gorman. []. División Paleontología Vertebrados, Museo de La Plata, Universidad Nacional de La Plata, Paseo del Bosque s/n., B1900FWA, La Plata, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Rodolfo A. Coria. []. Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río NegroSubsecretaría de Cultura de NeuquénMuseo Carmen Funes, Av. CVórdoba 55 (8318), Plaza Huincul, Neuquén, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina.  相似文献   

6.
This article evaluates the impact of opposition originating at the national level on affirmative action policies in 13 Texas cities in the late 1980s and early 1990s. We find that increased national hostility to affirmative action in hiring and contracting has had little effect on the content and strength of affirmative action programs in Texas municipalities. In fact, most programs have been maintained or strengthened since the 1980s. However, there is no clear and consistent relationship between the strength of municipal programs and either minority political representation or the size of a city's minority population. City size appears to be a relevant, but not decisive, factor in maintaining comprehensive policies. As such, we explore two additional hypotheses—policy time lag and bureaucratic insulation—to account for the survival and strengthening of municipal affirmative action policies in the 1990s.  相似文献   
7.
Beginning in the 3rd millennium BC, complex societies and states arose in the northern Horn of Africa. This process culminated with the development of the Kingdom of Aksum in northern Ethiopia and Eritrea in the 1st millennium AD. The development of these polities can be outlined in principle on the basis of the archaeological evidence. The process consisted of at least two distinct trajectories to social complexity, indirectly related to each other in the Eritrean–Sudanese lowlands and the Eritrean–Ethiopian highlands, respectively, with a shift in the location of complex societies from the lowlands to the highlands in the early 1st millennium BC. This shift was due to changes in the general pattern of interregional contacts between the regions facing the Mediterranean Sea and Indian Ocean along the Nile Valley, Red Sea and western Arabia from the 4th millennium BC to the 1st millennium AD.  相似文献   
8.
This paper reports the combined preliminary results of the Italian Mission to Kassala and the joint University of Khartoum/Southern Methodist University Butana Project. Both groups have been carrying out extensive survey and test excavations in the Southern Atbai of the East Central Sudan, between the Atbara and Gash Rivers. This work has led to the recognition of a previously unknown culture area and ceramic tradition which spans about 5000 years and, at its peak, probably covered about 100,000 sq. km east of the Nile. This ceramic tradition, the Atbai Tradition, is associated with the development of large villages (over 10 ha) during the 4th millennium bc.
Résumé Le présent article rapporte les résultats préliminaires combinés de la Mission italienne à Kassala et du projet Butana entrepris en commun par les universités de Khartoum et Southern Methodist. Ces deux groupes ont réalisé des reconnaissances archéologiques extensives et des sondages dans le sud de l'Atbai, dans la partie centrale orientale du Soudan, entre les rivières Atbara et Gash. Leur travail a mené à la reconnaissance d'une civilisation et d'une tradition céramique auparavant inconnues qui durèrent quelque 5000 ans et qui couvraient à leur apogée environ 100,000 km2 à l'est du Nil. Cette tradition céramique, la tradition Atbai, est associée au développement des grands villages (de plus de 10 ha) au cours du 4e millénaire avant notre ère.
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