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201.
202.
M. Bhandari S. D. Bharti M. K. Shrimali T. K. Datta 《Journal of Earthquake Engineering》2018,22(6):989-1007
The behavior of base-isolated building frame is investigated with the help of a numerical study for far-field and near-field earthquakes with directivity and fling-step effects. Both design-level and extreme-level earthquakes are considered. Selected response parameters are peak floor displacement, acceleration, base shear, and isolator displacement. Inelastic behavior of base-isolated structure during the earthquake is investigated performing nonlinear time history analysis of a ten-story building frame. This study shows that base isolation is not effective for near-field earthquakes. Even for design-level earthquake, the frame gets significantly into inelastic range for earthquakes with fling-step effect. 相似文献
203.
L. Ragni D. Cardone N. Conte A. Dall’Asta A. Di Cesare A. Flora 《Journal of Earthquake Engineering》2018,22(10):198-230
ABSTRACTThis paper reports on results of nonlinear analyses performed within the RINTC project on an RC building isolated with different systems (High Damping Rubber Bearings, High Damping Rubber Bearings and Flat Sliding Bearings, Friction Pendulum System) and designed according to the Italian design code. The seismic response has been evaluated under different seismic input levels of two sites with different hazard and by considering two Limit States: Global Collapse and Usability-Preventing Damage. The influence of seismic stoppers and modelling uncertainties is also evaluated. Results permit to compute the implicit collapse risk and to identify critical aspects of current design procedures. 相似文献
204.
Eric D. Tourigny 《International Journal of Historical Archaeology》2018,22(4):843-864
Much of the meat consumed in nineteenth-century southern Ontario (Upper Canada) came in the form of preserved barreled products. The specific ways of obtaining, preparing and consuming these products resulted in unique regional foodways. Through analyses of historical and archaeological evidence, this paper investigates how barreled meat was packed, shipped and purchased in Upper Canada and discusses the various ways its consumption impacted the lives of its residents and contributed to the formation of local identities. An investigation of butchery marks and body portion distributions lead to a possible method for archaeologically distinguishing between barreled and non-barreled meat assemblages. 相似文献
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Michael L. Brennan Frank Cantelas Kelley Elliott James P. Delgado Katherine L. C. Bell Dwight Coleman Allison Fundis Jack Irion Hans K. Van Tilburg Robert D. Ballard 《Journal of Maritime Archaeology》2018,13(2):97-121
Telepresence-enabled exploration of deep sea environments has developed over the past 30 years, providing access to archaeologists, scientists, and the general public to sites otherwise inaccessible due to depth. Pioneered through the inception of the JASON Project in the late 1980 s, telepresence missions have expanded to two dedicated ships of exploration, NOAA Ship Okeanos Explorer and exploration vessel Nautilus, and has been implemented on a series of opportunistic missions on other vessels. This paper chronicles the history of the use of telepresence for the exploration of shipwrecks in deep water as well as how this capability has allowed the public to engage with such missions. Broadening the scope of who can explore the deep sea, telepresence has also expanded what is observed and documented in the deep, which speaks to humanity’s use of the maritime world and an archaeology of discard through our material disposed of into the deep sea. 相似文献
208.
Carla Ceraldi Maria Lippiello Claudio D’ambra Andrea Prota 《International Journal of Architectural Heritage》2018,12(3):362-375
ABSTRACTThe employment of timber pegs in timber structure joints is a widespread technology in the field of timber frame building in the United States, where the Timber Frame Engineering Council has published a special Standard to supplement the National Design Specification for Wood Construction. The authors have been studying the possibility of supplementing the Eurocode 5 design formulas, thought for timber joints with metal connectors, with specifications needed for a reliable design when employing timber pegs. The field of application envisaged is that of restoring timber structures and results obtained until now are quite encouraging. In this step of the research, more attention has been paid to deformation process: fir and chestnut samples have been tested to determine their dowel-bearing behavior with steel and ash timber peg while double-shear plane joints made of the same wood species, and fastened with steel as well as timber pegs, have been analyzed. 相似文献
209.
J. Petřík D. Sosna L. Prokeš D. Štefanisko P. Galeta 《Archaeological and Anthropological Sciences》2018,10(4):893-904
Despite the large-scale expansion of Bell Beaker phenomenon, there is a tension between the normative Bell Beaker material culture categories and their local objectification in the form of real artefacts. Stone projectile points provide an opportunity to evaluate how much was the general category of such a point influenced by regional and local factors. The aim of this paper is to explore shape and size variation of Central European Bell Beaker projectile points from Moravia (Czech Republic) to elucidate factors responsible for this variation. The sample consists of 194 projectile points from 54 Central European Bell Beaker sites (2500–2300/2200 BC) distributed in Morava River catchment. The size and shape of projectile points were studied by landmark-based geometric morphometrics and expressed as shape groups, which have been assessed in terms of their spatial distribution, raw material, and reutilization. Although several shape categories of points were identified, there is a strong degree of uniformity in the research sample. The dominant shape category (75.4 % of points) was pervasive across geographic space and was not significantly affected either by raw material or reutilization. A lower degree of reutilization of points is interpreted as a consequence of a non-utilitarian role of projectile points, which represented a critical component of Bell Beaker mortuary practices. 相似文献
210.
During late winter and spring, hunter-gatherers in temperate, subarctic, and arctic environments often relied on diets that provided marginal or inadequate caloric intakes. During such periods, particularly when stored food supplies dwindled or were used up entirely, lean meat became the principal source of energy. Nutritional problems associated with high-protein, low-energy diets are discussed. These problems include elevated metabolic rates, with correspondingly higher caloric requirements, and deficiencies in essential fatty acids. The relative benefits of adding fat or carbohydrate to a diet of lean meat are evaluated in light of the protein-sparing capacities of these two nutrients. Experimental data indicate that although both enhance high-protein, low-energy diets, carbohydrate is a more effective supplement than fat. Given the nutritional inadequacies of a lean-meat diet, the paper concludes with a discussion of alternative subsistence strategies that increase the availability of carbohydrate or fat at the critical time of year. 相似文献