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31.
Katia Bernardeschi Cristina Padovani Giuseppe Pasquinelli 《Journal of Cultural Heritage》2004,5(4):92
The paper describes the numerical techniques implemented in the finite-element code NOSA for structural analysis of masonry constructions. The code is then applied to the analysis of “Buti’s bell tower”, a medieval structure located on the Pisa mountains, under two different conditions: firstly, with the structure subjected to its own weight alone, and then while subjected to both its own weight and a horizontal load, which models an earthquake. The displacement and stress fields, as well as the distribution of cracking have been calculated with NOSA, and the numerical results analysed and compared to the actual distribution of fractures in the tower. 相似文献
32.
G. Giachi S. Lazzeri M. Mariotti Lippi N. Macchioni S. Paci 《Journal of Cultural Heritage》2003,4(4):269-283
During the excavation of the Etruscan and Roman harbour of Pisa, several shipwrecks were found. The wooden timbers constituting the ship C and ship F (which date back to the first and the second century A.D., respectively, as attested by archaeological findings) were selected in order to collect information about the technological knowledge of the time. Pinus pinaster Aiton was essentially utilised for the planking of ship C and Quercus sp. caducifolia for that of ship F. The choice of timber for the other parts of ship C hull was much more differentiated. Ship C seems to be built in a careful way and its characteristics when added to its overall lightness, seem to reflect its use as a higher capacity boat built for sea sailing. Ship F seems more linked to short voyages in inner fresh waters. The utilisation of different woods was linked not only to the technological characteristics of wood, but also to their easy availability. Palynological analysis, carried out on the clay sediments embedding the shipwrecks, has shown that the flora of Pisa area in that time period would have allowed the acquisition of all the timber species used for both the ships’ construction, with the exception of the fig wood. However, a foreign origin of the timber from somewhere else in the Northern Mediterranean area has not been excluded. 相似文献
33.
Reading and written spelling skills for words and non-words of varying length and orthographic complexity were investigated in normal Italian first and second graders. The regularity and transparency of the mapping between letters and phonemes make Italian orthography an unlikely candidate for discrepancies between reading and spelling to emerge. This notwithstanding, the results showed that reading accuracy is significantly better than spelling. The difference is particularly striking in first graders, but it is still evident in 2nd graders, though most strongly on non-words. The data show that reading and written spelling are non parallel processes and that the developmental asynchrony reflects a partial structural independence of the two systems. 相似文献
34.
The impact of the geographical origin of patents on the probability of an opposition being filed and a patent being revoked has been examined in this paper, after accounting for patent value indicators and industry specificities. The study is based on a dataset of approximately 450,000 EPO granted patents and 24,000 patent opposition cases in the years 2000–2008. We find that patents with a first priority in the US are less likely to be challenged, although they are relatively more likely to be revoked than patents with a priority in a member country of the European Patent Convention. Patents from Japan have less probability of being opposed and are less likely to be revoked than the other countries. A disaggregation of the European countries has revealed that patents with a German priority have a higher or similar likelihood of being opposed than patents from the other countries, with the exceptions of The Netherlands and Denmark. 相似文献
35.
Paola Zamparo Giuseppe Carignani Luca Plaino Barbara Sgalmuzzo Carlo Capelli 《Journal of sports sciences》2013,31(1):75-81
Abstract In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output ([Wdot] tot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake ([Vdot]O2) allowed the computation of the “overall” efficiency of locomotion (η o = [Wdot] tot / [Vdot]O2). Mean η o was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, [Wdot] tot was then obtained from η o and measures of [Vdot]O2. The power to overcome (passive) drag was calculated as [Wdot] d = D · v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as η p = [Wdot] d / [Wdot] tot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in η p and [Wdot] d explain why at the highest speed tested (～3 m · s?1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m · s?1. 相似文献
36.
Laura Chimenti Giuseppe Morici Alessandra Paternò Anna Bonanno Marcello Vultaggio Vincenzo Bellia 《Journal of sports sciences》2013,31(9):925-935
Abstract Runners have increased numbers of neutrophils in the airways at rest and after exercise compared with sedentary individuals. The aim of this study was to determine whether Mediterranean seasonal changes in temperature, humidity or airborne pollutants affect the airway cells of runners training outdoors in an urban environment. In nine male amateur runners, cell composition, apoptosis, and inflammatory mediators were measured in induced sputum collected at rest (baseline) and the morning after races held in the fall (21 km), winter (12 km), and summer (10 km). Concentrations of air pollutants were below the alert threshold at all times. Neutrophil differential counts tended to increase after all races (P = 0.055). Apoptosis of neutrophils increased with ozone (P < 0.005) and particulate matter <10 μm (PM10) (P < 0.05) exposure. Bronchial epithelial cell counts were low at all times and weakly correlated with ozone and PM10 concentrations. Apoptotic bronchial epithelial cells increased after all races (P < 0.05). Inflammatory mediators in induced sputum were low at baseline and after the races, and correlated with neutrophil differential counts only at rest. In conclusion, apoptosis of airway cells in runners appears to be affected by both exercise and environmental conditions. Apoptosis of neutrophils increased with exposure to environmental pollutants while apoptosis of bronchial epithelial cells increased after intense exercise. Since no relationship was observed between neutrophil counts and inflammatory mediators 20 h after races, airways inflammation at this time point appears blunted in healthy runners and little affected by exposure to mild seasonal changes and airborne pollutants. 相似文献
37.
Giuseppe Lippi Giuseppe Banfi Massimo Franchini Gian Cesare Guidi 《Journal of sports sciences》2013,31(5):441-442
Abstract Doping in sports is commonplace. The prevention of harm to the athlete, the guarantee of fair play, and a level playing field for all competitors are the basis of the current anti-doping strategies. As healthcare systems are forced to allocate increasing resources to prevent and treat the prevailing pathologies worldwide, funding for anti-doping campaigns will necessarily be restricted. Ideally, additional resources should be devoted to increasing the number of athletes tested, the panels of tests used, and the frequency of out-of-competition controls. Since doping prevention cannot be considered a priority for most healthcare systems, such an approach is unaffordable and an alternative framework should be devised, focused primarily on harm reduction rather than fair play. The identification of abnormal deviations from reference values, regardless of pathological or artificial causes, would allow the athlete to be followed and tested using conventional laboratory tests, which are affordable to governments and healthcare systems and available to clinical laboratories. Although this strategy would not detect cheating, it would safeguard athletes' health. 相似文献
38.
This article addresses some of the most important legal and ethical issues posed by robot companions. Firstly, we clarify that robots are to be deemed objects and more precisely products. This on the one hand excludes the legitimacy of all such considerations involving robots as bearers of own rights and obligations, and forces a functional approach in the analysis. Secondly, pursuant to these methodological considerations we address the most relevant ethical and legal concerns, ranging from the risk of dehumanization and isolation of the user, to privacy and liability concerns, as well as financing of the diffusion of this—still expensive—technology. Solutions are briefly sketched, in order to provide the reader with sufficient indications on what strategies could and should be implemented, already in the design phase, as well as what kind of intervention ought to be favored and expected by national and European legislators. The recent Report with Recommendations to the Commission on Civil Law Rules on Robotics of January 24, 2017 by the European Parliament is specifically taken into account. 相似文献
39.
Dan Wang Giuseppe De Vito Massimiliano Ditroilo Eamonn Delahunt 《Journal of sports sciences》2017,35(16):1582-1591
The purpose of this study was to investigate the influence of sex and fatigue on knee extensor peak torque (PT), muscle stiffness (MS) of the vastus lateralis (VL) and knee joint musculoarticular stiffness (MAS) in young adults. Twenty-two male and 22 female recreational athletes participated. Males were characterised by higher relaxed [pre-: males 364.43 (52.00) N · m–1, females 270.27 (37.25) N · m–1; post-: males 446.75 (83.27) N · m–1, females 307.39 (38.58) N · m–1] and contracted [pre-: males 495.07 (71.04) N · m–1, females 332.34 (85.42) N · m–1; post-: males 546.37 (90.74) N · m–1, females 349.21 (85.55) N · m–1] MS of the VL, and knee joint MAS [pre-: males 1450.11 (507.98) N · m–1, females 1027.99 (227.33) N · m–1; post-: males 1345.81 (404.90) N · m–1, females 952.78 (192.38) N · m–1] than females pre- and post-fatigue. A similar finding was observed in pre-fatigue normalised knee extensor PT [pre-: males 2.77 (0.42) N · m kg–1, females 2.41 (0.40) N · m kg–1, post-: males 2.53 (0.54) N · m kg–1, females 2.26 (0.44) N · m kg–1]. After the fatigue protocol, normalised knee extensor PT and knee joint MAS decreased, whilst relaxed and contracted MS of the VL increased in both sexes. These observed differences may contribute to the higher risk of knee injury in females and following the onset of fatigue. 相似文献
40.
Evagelos D. Lioutas Chrysanthi Charatsari Majda Černič Istenič Giuseppe La Rocca Marcello De Rosa 《The Journal of Agricultural Education and Extension》2019,25(2):139-160
Purpose: Considering current debates on ecosystem services’ effectiveness and the AIS/AKIS functioning, in this study we suggest a new, systemic way to evaluate extension systems (ESs). Using this model, we compared the effectiveness of ESs in three countries with essential differences but also characteristic similarities in their agricultural sectors: Greece, Italy and Slovenia.
Design/methodology/approach: Initially, we defined ‘extension system’ as a wide range of actors integrating resources with the aim of co-producing value (not for but with) farmers. To capture the value flow within this constellation of actors we distinguished between the notion of ‘value in production’ – i.e. the value embodied in service offerings – and the value emanating when service content is used in real settings or ‘value in use.’
Findings: Our approach revealed that, despite their structural and organizational differences, the ES in the three countries share common problems arising from a limited focus on the issue of value in use.
Practical implications: The application of a systemic approach – seeing farmers as co-creators and not as end-users of extension services – in the evaluation of ESs contributes to better understand the complexity of value flow within the system and can strengthen extension systems’ effectiveness.
Theoretical implications: The present study, by reconsidering traditional evaluation approaches and by focusing on value co-production, offers an alternative value-centric framework for the conceptualization of extension services and points out to the need for refining the evaluation criteria of ESs.
Originality/value: Our work, by emphasizing the reciprocal creation of value within ESs, and by adding the concept of value in use, offers a new systems approach worth considering when evaluating ESs within different organizational and sociocultural contexts. 相似文献