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11.
《History & Technology》2012,28(3):281-309
Prior to the launch of Sputnik, knowledge about human space travel was widely circulated by spaceflight proponents, scientists and news producers in mainstream culture through print, film and broadcast media and displayed in public sites such as museums and public exhibition spaces. Focusing on the timeframe 1947–1953, this article examines how key members of the British Interplanetary Society used a combination of craft skills, graphical technologies, and communication media to create pictures and models to support rhetorical claims that spaceflight and astronautics are legitimate fields of scientific research and space travel could and should be achieved in the near future. Production and circulation of factual knowledge about space travel was not confined to material and discursive practices in established fields such as astronomy and aeronautical engineering. Actors from other professional, non-professional, and social groups contributed to the realization of future spaceflight as an heterogeneous cultural endeavor or astroculture encompassing an array of technical processes, artifacts, craft skills, and scientific knowledge.  相似文献   
12.
Geoinformation technologies are applied to an analysis of the living environments of Paleolithic people, using a territory along the route of a future gas pipeline planned for construction in the Altai Mountains as an example. GIS modeling of a paleoenvironment is based on the notion of a paleolandscape's geological and morphological framework. The SRTM digital model of terrain, and geological maps of scale 1: 200,000 were used. The main factors that control localization of sites have been selected: the presence of flat, even grounds suitable for settlement; proximity to sources of raw materials; good conditions for sun exposure; and water availability across the territory. Verification of known Paleolithic sites showed the adequacy of GIS-modeling and its suitability in the optimal search for new sites.  相似文献   
13.
Although the people of Bangladesh and the state of West Bengal in India share common cultural practices, they differ in contraceptive adoption and practice. The use of modern contraceptive methods among women and couples of the two Bengals differ from each other. The use of natural method is significantly higher among women and couples in West Bengal compared to that of their counterparts in Bangladesh. The study analyses data from Demographic and Health Survey (DHS) using sequential logit models. Results show that greater reliance on natural methods among women of West Bengal is related to higher preference for sons compared to that in Bangladesh.  相似文献   
14.
How do votes disperse through a territory? Studies of spatial voting patterns have largely focused on the influence of local factors on voting. The “Friends and Neighbors” model (Key (1949)) explains the advantage of candidates running for office in the locality with which they are associated (Arzheimer and Evans (2012, 2014): Collignon and Sajuria (2018); Horiuchi et al. (2018); Jankowski (2016); Hunt (2020); Munis (2021)), and the “neighbor” effect helps to explain why votes spread. More recent studies have found that the dispersion of votes decreases with distance (Put et al. (2020); Arzheimer and Evans (2012)). However, we know little about how spatial patterns of voting emerge or the mechanism behind the neighbor effect. We argue that this effect depends on the neighbors’ access to information about a candidate, which is constrained by the way information flows. Although scholars have argued that information is a relevant driver explaining the dispersion of votes (Bowler et al. (1993); Arzheimer and Evans (2012); Evans et al. (2017); Campbell, Cowley, Vivyan, and Wagner (2019)), no research has examined the relevance of the network through which information flows. We propose that a spatial interaction model (Wilson (1971)) allows us to predict where this information flows or the voting pattern that will form. Taking advantage of a quasi-natural experiment in Brazilian legislative elections in 1974 and 1978, we show that votes spread through areas of influence created by a hierarchy of cities based on the flows of exchanges among them, including information. We then use our spatial interaction model to predict voting patterns in the elections of 1978 using data from the 1974 elections. Our findings show that the spatial interaction model results fit the data quite well and can help predict spatial patterns of voting.  相似文献   
15.
This article discusses attempts to define culture and civilisation in early twentieth-century Romania on the basis of two fundamental Romanian models of development: the theory of forms without substance and the theory of synchronism. The former is studied here primarily in relation to the views of Titu Maiorescu (1840–1917) and Constantin Radulescu-Motru (1868–1957) and the latter in relation to the views of Eugen Lovinescu (1881–1943). While the theory of forms without substance asserts a would-be ‘traditional’ and ‘organic’ development of Romanian culture and civilisation, the theory of synchronism proposes a development according to the ‘spirit of the age’ and the ‘law of simulation-stimulation’. In the present study, these opposed models of development are observed in relation to the general tendencies towards a pronounced critical spirit and towards discussing cultural vs. structural changes or culture vs. power in late nineteenth-century and early twentieth-century Europe. The Romanian models of development are also studied on the background of wider European discussions on Enlightenment and modernism, historicism, conservatism and liberalism, German vs. French influence and nationalist vs. cosmopolitan attitudes.  相似文献   
16.
The dynamic finite element equations of a two-dimensional structure made of axial-flexural frame elements with tendon-driven actuators have been derived. A critical review of classical optimal control theory is made with respect to its application to the control of structure under seismic excitations. Seven control algorithms, including two newly proposed algorithms, have been described, investigated and discussed. The need of an optimal observer, Kalman filter, is discussed. The validity of separation theorem applicable to the optimal stochastic control of structure for earthquake resistance is shown. How the control system perform under the circumstances of actuator saturation is also shown. Several numerical examples are worked out to demonstrate and compare the efficiency and limitations of those control algorithms.  相似文献   
17.
A constitutive model for predicting the cyclic response of reinforced concrete structures is proposed. The model adopts the concept of a smeared crack approach with orthogonal fixed cracks and assumes a plane stress condition. Predictions of the model are compared firstly with existing experimental data on shear walls which were tested under monotonic and cyclic loading. The same model is then used in the finite element analysis of a complete shear wall structure which was tested under a large number of cyclic load reversals due to earthquake loading at NUPEC's Tadotsu Engineering Laboratory. Two different finite element approaches were used, namely a two-dimensional and a three-dimensional representation of the test specimen. The ability of the concrete model to -reproduce the most important characteristics of the dynamic behaviour of this type of structural element was evaluated by comparison with available experimental data. The numerical results showed good correlation between the predicted and the actual response, global as well as local response being reasonable close to the experimental one.  相似文献   
18.
This paper describes the numerical simulation of the seismic behaviour of a mock-up of a six-floor building, constituted by two parallel R/C walls and experimentally tested on a shaking table. Within the scope of an international benchmark the mock-up was submitted to three earthquakes with intensities up to 0.71 g, which induced nonlinear behaviour in the concrete and reinforcement. For the numerical simulations concrete is discretised with 2D finite elements, and its behaviour reproduced via a constitutive model with two scalar damage variables. Steel rebars are discretised with 2-noded truss elements, and their constitutive behaviour under cyclic conditions reproduced by the Menegottb-Pinto model. Specific attention is devoted to Rayleigh damping, focusing on two different strategies: (i) disregarding the damping contribution, or (ii) adopting a damping matrix that takes into account the stiffness changes during the nonlinear analyses. Main results and strategies for simulating the benchmark axe presented, with emphasis on the comparison between the numerical and the experimental results, which show good agreement when the damping contribution is neglected.  相似文献   
19.
A model is proposed for the incremental force-deformation behaviour of reinforced concrete sections and members, under generalised load or deformation histories in 3D, including cyclic loading, up to ultimate deformation. At the section level the model is of the Bounding Surface type and accounts for the coupling between the two directions of bending and between them and the axial direction. For the construction of the member tangent flexibility matrix on the basis of the section tangent flexibility matrix, a piecewise-linear variation along the member is assumed for the nine terms of the tangent section flexibility matrix. Model parameters are derived on the basis of available test results for: (a) the force-deformation response under cyclic biaxial bending with normal force; (b) the hysteretic energy dissipation; (c) the secant-to-yield member stiffness, and (d) the ultimate deformation of the member under cyclic biaxial load paths.  相似文献   
20.
An experimental study on half-scale brick-masonry models with different strengthening and retrofitting measures has been studied under cyclic loading in a quasi-static test facility. The strengthening measures undertaken for the studies axe the horizontal bond beam at the lintel and sill level with a combination of vertical reinforcement at corners and openings. The retrofitting measures studied are grouting with epoxy-sand-mortar and cement-grout-injection with welded wire mesh in the cracked region. The tests reveal that the horizontal bond beam at lintel level with vertical reinforcement is effective in reducing the cracking above the lintel level. The insertion of an additional sill-band signi-ficantly reduces the cracking in walls. The epoxy-sand-mortar techniques for retrofitting of cracked regions prove to be effective enough to restore the initial strength, stiffness and deformation capacity. Although specimen retrofitted with cement-grout-injection with welded wire mesh is effective to regain the ultimate strength yet the brittle failure is observed as the specimen is stressed beyond the elastic limit.  相似文献   
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