1,598 research outputs found

    The sea in Sumerian literature

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    Surveying the references to the sea in Sumerian literature, this paper discusses the general idea that the sea is underrepresented in Mesopotamian cultures of the third millennium BCE. The common idea on Mesopotamian civilizations is that these were based on the rivers. However, recent research suggests the early Mesopotamian urban settlements of the third millennium BCE are on the ancient coast of the Persian Gulf and in the middle of lagoons or marshes. Coastal marsh cultures would not only have looked at the mainland, but also to the sea. Through a study of Sumerian literature and royal inscriptions, the historical relationship of the Mesopotamian cultures with the Persian Gulf is discussed. The image of the sea that emerges from literary sources reflects the changes that occurred in coastal region of southern Iraq during the third millennium BCE

    Pleiades in ancient Mesopotamia

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    In this paper I will analyse the different features of the Pleiades in the astronomical, astrological, and calendrical interpretation as well as their mythical and cultural background in ancient Mesopotamia. According to cuneiform sources, the Pleiades are among the most important stars. They are simply known in Sumerian as ―the Stars‖ (MUL.MUL), while their Akkadian name, ―the Bristle‖ (zappu), links them to the imagery and the cultural context of the ―Bull of Heaven‖ constellation (Taurus), to which they belong. Pleiades are frequently depicted as seven dots or seven stars, and identified on a mythological level with groups of seven divine beings. In fact, the Sumerian ideogram for ―seven‖ is used as an alternative name for the Pleiades. In particular they show a close relation to a group of demons, called the Seven (Sebēttu), that, according to an etiological myth, causes the eclipse of the moon. The relation of the Pleiades to the war and death sphere is strengthened by their association with the Netherworld god Nergal/Erra, as well as their identification with the god’s planet (Mars). Finally, the Pleiades are among the few celestial bodies that receive a cult, and specific prayers are dedicated to them. From the sources it emerges that the Pleiades are mainly related to the movement of the Moon, and it is worth noting that the list of constellations of the ecliptic begins precisely with the Pleiades. Furthermore, the Pleiades play an important part in the calendrical reckoning, a role that is clearly stated in almanacs as the MUL.APIN, as well as in the intercalation scheme based on the conjunction of the Moon and the Pleiades

    Competency-based assessment for the training of PhD students and early-career scientists.

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    The training of PhD students and early-career scientists is largely an apprenticeship in which the trainee associates with an expert to become an independent scientist. But when is a PhD student ready to graduate, a postdoctoral scholar ready for an independent position, or an early-career scientist ready for advanced responsibilities? Research training by apprenticeship does not uniformly include a framework to assess if the trainee is equipped with the complex knowledge, skills and attitudes required to be a successful scientist in the 21st century. To address this problem, we propose competency-based assessment throughout the continuum of training to evaluate more objectively the development of PhD students and early-career scientists. © 2018, Verderame et al

    A practice-oriented approach for the assessment of brittle failures in existing reinforced concrete elements

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    A practice-oriented approach was used to assess shear failures in existing reinforced concrete (RC) elements. A simple tool, in form of non-dimensional domains, is obtained considering the capacity models suggested by European and Italian codes. The reliability of failure domains depend strictly on the reliability of the shear capacity model employed; thus, a critical review of code and literature analytical formulations was also carried out. Sezen and Moehle’s experimental database was, then, used to compare the different shear capacity models considered. The code and literature review of shear capacity models emphasizes differences and affinities of the analytical approaches followed in different countries. The domains carried out can be used as a practical instrument aimed at checking shear–flexure hierarchy in existing RC elements and contextualized in the framework of preliminary assessment given the character of input information required. Preliminary applications of the domains are also provided, and emphasize the effectiveness of the new tool for detailed and large scale assessment of existing RC structures

    Analytical versus observational fragilities::the case of Pettino (L’Aquila) damage data database

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    A damage data database of 131 reinforced concrete (RC) buildings, collected after 2009 L’Aquila (Italy) earthquake, is employed for the evaluation of observational fragility curves. The specific interpretation of damage data allowed carrying out fragility curves for slight, moderate, and heavy damage, (i.e., DS1, DS2, and DS3), defined according to EMS 98 macroseismic scale. Observational fragility curves are then employed for the calibration of FAST analytical methodology. FAST method is a spectral based approach, meant for the estimate of fragility curves of infilled RC buildings up to DS3, evaluated, again, according to EMS98. Kullback–Leibler divergence is employed to check the matching between analytical and observational fragilities. FAST input variables can vary in quite large ranges and the calibration provides a valuable suggestion for the application of the method in other cases in which field damage data are not available. Results showed that optimizing values, for the input variables calibrated, are in good agreement with typical values assumed in literature. Analytical results showed a very satisfactory agreement with observational data for DS2 and DS3, while systematical underestimation was found for the case of DS1

    6th April 2009 L'Aquila earthquake, Italy:Reinforced concrete building performance

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    On 6th April 2009 an earthquake of magnitude M (w) = 6.3 occurred in the Abruzzo region; the epicentre was very close to the city of L'Aquila (about 6 km away). The event produced casualties and damage to buildings, lifelines and other infrastructures. An analysis of the main damage that reinforced concrete (RC) structures showed after the event is presented in this study. In order to isolate the main causes of structural and non-structural damage, the seismological characteristics of the event are examined, followed by an analysis of the existing RC building stock in the area. The latter issue came under scrutiny after the release of official data about structural types and times of construction, combined with a detailed review of the most important seismic codes in force in the last 100 years in Italy. Comparison of the current design provisions of the Italian and European codes with previous standards allows the main weaknesses of the existing building stock to be determined. Damage to structural and non-structural elements is finally analyzed thanks to photographic material collected in the first week after the event; the main causes of damage are then inferred

    Influence of infill panels on the seismic behaviour of a r/c frame designed according to modern buildings codes

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    It has been broadly shown that presence of infill panels as closing elements of R/C frame buildings has a significant influence on global structural behaviour. Nevertheless, infill elements are not usually considered in the modelling process during the design phase. The present work investigates the effect of infill masonry walls on the dynamic characteristics of a R/C MRF building, designed according to a modern seismic building code, and on its seismic performance at different levels of seismic intensity. An analytical investigation is carried out through eigenvalue analysis on both bare and infilled structure, in order to calibrate the elastic properties of the concrete and infills according to in situ tests; nonlinear static analyses are also performed to characterize the inelastic behaviour. The infill system considerably affects the behaviour of the examined structure, in agreement with earlier studies related to very simple and usually ¿unrealistic¿ structures. This result becomes more reliable due to the consistency between the results of the eigenvalue analysis and the experimental dynamic data

    Il ruolo degli effetti di sito sulla risposta strutturale degli edifici nella conca aquilana

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    Il terremoto de L’Aquila del 6 aprile 2009 è stato significativamente caratterizzato dagli effetti di sito, evidenziati sia dalla variabilità delle registrazioni accelerometriche in zona near fault che dalla disuniforme distribuzione del danno rilevato. In particolare, nel quartiere aquilano di Pettino, in corrispondenza di un complesso residenziale composto da sette edifici della stessa tipologia strutturale, è stato osservato un danneggiamento molto diversificato. La nota riporta i risultati di una serie di analisi di risposta sismica locale 1D, condotte in corrispondenza di alcuni degli edifici del quartiere, per i quali si disponeva di indagini geotecniche di dettaglio, finalizzate a valutare l’influenza degli effetti di sito sulla risposta delle strutture. I risultati delle analisi condotte in condizioni di campo libero hanno mostrato significative amplificazioni del moto proprio in corrispondenza delle frequenze fondamentali del moto di input. Le analisi del sistema sottosuolo-edificio, condotte mediante l’utilizzo di un codice con formulazione a masse concentrate hanno inoltre consentito di verificare l’incidenza dell’interazione inerziale sul moto in superficie, nonché di riprodurre in forma semplificata il meccanismo di piano soffice osservato
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