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1.
We perform a probabilistic seismic hazard analysis (PSHA) for broad-band strong ground motion within the Saronikos Gulf region, Greece, from potential earthquakes along the 30 km long Aigina fault in the northern part of the Gulf. We perform the PSHA utilizing empirical Green’s functions (EGFs) merged with synthetic Green’s functions (SGFs) along with models of finite rupture in place of standard “attenuation relations.” Our approach considers all significant magnitudes for PSHA and full broadband ground motion simulations. Calculations are source and site specific, and could reduce uncertainties in estimating standard engineering parameters. We use a range of rupture scenarios for all significant magnitude earthquakes along the fault. The hazard calculation is for frequencies 0.0– 15.0 Hz. Recordings of small earthquakes from an onshore/offshore local seismic array were used as EGFs for frequencies of 1.5–15.0 Hz, the finite difference code E3D was utilized to synthesize SGFs for frequencies 0.0–1.5 Hz, and an algorithm for merging the EGFs with SGFs was developed. The full-waveform calculations are important for non-linear dynamic analysis of structures in the coastal zone and potential hazard to long period structures. Results of proposed PSHA identify 2%, 10%, and 50% hazard at the selected sites of Saronikos Gulf.

Finally, we compare our PSHA results to those obtained by standard practice which involves prediction equations (GMPEs) recently developed in the Next Generation Attenuation (NGA) project and empirical predictive attenuation relations proposed for Greece. We believe that differences with the NGA results are due to site- and source-specific information utilized in this study, and incorporation of this information may significantly reduce the uncertainty in seismic hazard calculations.  相似文献   

2.
The aim of this article is to investigate the ground motion attenuation of the most industrialized and populated regions of Italy, evaluating the capability of different approaches to estimate site dependent models. The 5.2 local magnitude earthquake on November 24, 2004 shocked the areas of Northern Italy producing damage of about 215 million euros. The data set, including 243 earthquakes of local magnitude up to 5.2, has been collected in the period December 2002–October 2005 by 30 three-component seismic stations managed by Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Milano (INGV-MI). Empirical attenuation relationships have been estimated for horizontal peak ground velocity (PGHV), acceleration (PGHA), displacement (PGHD), and for response spectral acceleration (SA) for periods between 0.1 and 1.5 s. To estimate suitable attenuation models, in particular for sites characterized by thick sedimentary geological formations, a soil discrimination based on EU8 code can lead to wrong evaluations. On the contrary, a classification based on H/V spectral ratios of seismic ambient noise (NHV) allows the models to fit better real and predicted data and to reduce the uncertainties of the process. For each receiver, NHV have been strengthened by additional H/V spectral ratio of earthquake data (EHV), calculated considering different portions of the analysed signals. In order to validate the PGHA attenuation relationship for greater magnitudes, accelerometric records, relative to Central-Northern Italy strong motions occurring in the last 30 years, have been collected and superimposed to our attenuation curves.  相似文献   

3.
Probabilistic seismic hazard is usually assessed by means of computer codes using seis-mogenic sources, parametric catalogues, seismicity rates and attenuation relationships. All these ingredients are conditioned by expert judgement that influences the final results. Even the attenuation relationships, though strictly based on experimental data, are considered a weak point due to the difficulty of modelling the interaction between seismic energy radiation and site response, and because earthquakes do not usually repeat themselves according to one theoretical model. Recently, methods making wide use of site intensity data have been developed in regions such as Italy, where the observed seismic history at selected sites is quite exhaustive. We analyzed these observations to assess seismic hazard at about 600 sites. We used a probabilistic counting technique, integrating the observations (when necessary), with computed shakings obtained from a logistic-type attenuation model. The results were then compared with the estimates provided by the recent seismic hazard map of Italy, compiled according to the traditional probabilistic seismic hazard approach. The match shows significant differences for some sites. A tentative explanation which seems to point to three alternatives is provided: (1) The mismatch between the two methodologies might appear because the stationary assumption has a poor fit with reality (at least in certain areas); (2) Some sites show a response that is systematically different from the average values predicted using attenuation relationships; (3) The definition of seismogenic zones leads to a bias in the seismicity rate estimate.  相似文献   

4.
The ‘digital revolution’ created new opportunities for private persons to participate in the public discourse on architecture and architectural heritage. But has this new ‘participatory culture’ also triggered democratic polyphony and a questioning of dominant (expert) values and knowledge? And when considering official Internet representations – is there a proactive policy involving citizens? Taking the ‘virtual life’ of the Vienna Werkbund estate (1932), a modernist icon listed as a national monument in 1978, as a case study, the present examination tempers exaggerated hopes. The analysis of private and official websites shows that new information and communication technologies foster the expression of different viewpoints only to a limited extent. Although residents use the Internet to voice criticism, actors situated outside expert culture primarily reaffirm the estate’s cultural value and act as co-producers of the dominant discourse. Focusing on official heritage, this paper not only provides evidence for the perpetuating function of new digital tools but also reveals the power relations that underpin paternalistic cultural mediation. Given the technological possibilities of involvement, it criticises official web representations for the exclusion of ‘the public’ and raises the fundamental question of what the digital mediation of cultural heritage in democratic societies should look like.  相似文献   

5.
社会、经济要素的空间离散化是精细化县级主体功能区划的重要需求,本文提出了一种基于模糊关系识别的空间数据离散化方法。该方法利用广义权距离实现对专家知识与多系统分层要素的综合集成,并通过建立待离散化要素与其影响指标的模糊关系识别模型,获得空间离散化权重。以2009年江苏省阜宁县人口、GDP以及经济发展水平的空间离散化为例进行实例分析。结果显示,本文提出的空间离散化方法具有较好的准确性与可信度,可较好揭示各影响要素对待离散要素的空间影响。  相似文献   

6.
Arthur Ruppin was the central figure in the Zionist colonization project in Palestine-Land of Israel in the decades preceded the establishment of the state of Israel. Ruppin's immense contribution gave him in Zionist historiography the title of ‘The Father of Jewish settlement in Palestine.’ Nevertheless, in spite of the title ‘Father’, Zionist historiography actually treats him as a ‘Zionist clerk,’ diminishing his role to an apolitical expert on bureaucracy and the economy. Exploring the reasons for his ambiguous position in Zionist historiography and memory, the historical account in the following article reveals how formative were his activities not only in the establishment of the bureaucratic field of the Yishuv (pre-state of Israel), but also in producing and disseminating the modern Hebrew identity models, consequently the article analyzes the relation of these models to the German-social Darwinist perceptions and practices, which shaped Ruppin's cultural identity, weltanschauung and actions.  相似文献   

7.
A seismic hazard analysis of Florence city was performed in the frame of a project concerning the dynamic behaviour of cable-stayed bridges. Both a probabilistic approach and a methodology based on the use of a local macroseismic catalogue were applied. A local catalogue was expressly compiled for this purpose, to collect the macroseismic intensities actually observed at the site as a result of past earthquakes. This sort of catalogue is an independent tool to verify the assumptions of the probabilistic approach (seismic zoning, earthquake recurrence relation, attenuation model), though it can supply results in terms of macroseismic intensity only and reflects the effective seismic history at the site, without taking into account any variability. The Cornell' methodology was used to assess probabilistic hazard in terms of macroseismic intensity, peak ground acceleration, peak ground velocity, and pseudovelocity uniform response spectra. The local catalogue points out level VII of the Mercalli-Cancani-Sieberg scale (MCS) as the maximum intensity historically observed in Florence. The probabilistic approach leads to the consideration of intensity VIII MCS as the maximum credible for the city. The probabilistic analysis in terms of ground motion was performed using attenuation relations estimated for alluvium sites, since the geology of Florence area is represented by fluvial and lacustrine deposits of various thickness. Peak ground acceleration values with 90% non exceedence probability in 50 and 500 years are respectively 145 and 219 cm/s's for a shallow alluvium site, and 95 and 157 cm/s's for a deep alluvium site; the corresponding peak ground velocity values for sites located on alluvium are 6.41 and 11.76 cm/s. Uniform response spectra are provided for shallow and deep alluvium sites, according to frequency-dependent attenuation relations estimated from strong Italian earthquakes.  相似文献   

8.
We present a scheme to modify empirical Green's functions by attenuation considering: (1) geometrical spreading; (2) decay in high frequency; (3) regional attenuation; and (4) phase of the signal. The accelerograms computed with the proposed simulation method are compared, in time and frequency domains, with strong ground motions from subduction and intermediate-depth earthquakes recorded in Mexico. It is shown that this simple empirical Green's functions technique can synthesize both the shape and amplitude of the response spectra in the site, considering a postulated seismic source located at different distances from the original one.  相似文献   

9.
New aspects of the frequency-dependent attenuation of the seismic waves travelling from Vrancea subcrustal sources toward NW (Transylvanian Basin) and SE (Romanian Plain) are evidenced by the recent experimental data made available by the CALIXTO'99 tomography experiment. The observations validate the previous theoretical computations performed for the assessment, by means of a deterministic approach, of the seismic hazard in Romania. They reveal an essential aspect of the seismic ground motion attenuation that has important implications on the probabilistic assessment of seismic hazard from Vrancea intermediate-depth earthquakes. The attenuation toward NW is shown to be a much stronger frequency-dependent effect than the attenuation toward SE and the seismic hazard computed by the deterministic approach fits satisfactorily well the observed ground motion distribution in the low-frequency band (<1Hz). The apparent contradiction with the historically-based intensity maps arises mainly from a systematic difference in the eigenperiods (type and size) of the buildings in the intra- and extra-Carpathians regions, thus the existing macroseismic data, based on buildings of small dimensions, i.e. with high eigenfrequency (5–10 Hz), can hardly be representative of the real hazard for new and large dimension, tall buildings, with eigenfrequency above 1 Hz.  相似文献   

10.
In the summer of 1561, a strong seismic sequence struck southern Italy, then the Spanish-ruled Kingdom of Naples. Both the Italian seismological tradition and the latest catalogues locate it in the Vallo di Diano (Diano Valley), a low-seismicity intermontane basin 100 km south-east of Naples. We explore the hypothesis that current perception of the 1561 earthquake is distorted by the nature of the historical dataset from which its parameters have been assessed, and which mostly derive from a single—albeit very detailed—primary source. We present and discuss several previously unconsidered original accounts. Our results cast doubts on the traditional interpretation of the earthquake, which could have been either one Vallo di Diano mainshock or several strong earthquakes within a time/space window compact enough for contemporary viewers to perceive them as one. Unquestionably, there is much more to the 1561 earthquake(s) than previously appeared. We hope that this groundbreaking effort will rekindle the interest of the seismological community in this seismic episode, our knowledge of which is still far from complete.  相似文献   

11.
To the extent that environmental governance aspires to be based on positive knowledge of what ‘the environment’ consists of and how it functions, programmes of environmental management must find ways to study it. This article draws on scholarship on knowledge infrastructures to examine a trajectory of scientific work in Ecuador focused on biodiversity and the recent uptake of this infrastructure for the study of climate change. When combined with an appreciation for the character of power and knowledge in modern institutions, analyses of experts’ ‘infrastructure work’ elucidate how environmental problems take shape as objects of expert intervention at the level of concrete, technical practices. Incorporating scientific infrastructure within the ambit of environmental anthropology can help us to understand the shape of environmental politics to come.  相似文献   

12.
Taking the Jharkhand region of India as a case study, this article uses empirical data to intervene in ‘women, environment and development’ and ecofeminist debates regarding women’s environmental knowledge. The article first outlines the adoption of gender/environmental issues into development planning and considers the dangers of overestimating women’s agroecological knowledges and assuming that they can easily participate in development projects. It then highlights the local complexities of environmental knowledge possession and control with reference to gender and other variations in agricultural participation, decision‐making and knowledge transfers between villagers’ natal and marital places. Particular emphasis is placed on the economic, socio‐cultural and ‘actor’ related factors that supplement gender as an influence on task allocation, decision‐making, knowledge distribution and knowledge articulation. The article concludes that given the socio‐cultural constraints women face in accumulating and vocalizing environmental knowledge, simplistic participatory approaches are unlikely to empower them. Instead, more flexible, site‐specific development initiatives (coupled with wider structural change) are required if opportunities are to be created for women to develop and use their agroecological knowledges.  相似文献   

13.
ABSTRACT

The big earthquake of August 24, 2016 and subsequent major shocks severely damaged many historic villages in Central Italy and dramatically showed the intrinsic vulnerability of the diffused architectural heritage. The St. Agostino church is one of the collapsed historical buildings, being inside the epicentre village of Amatrice. During the long seismic earthquake swarm, progressively the church was damaged and monitored. This multidisciplinary study of the damage of the church includes correlations of all the data derived from three steps geomatics surveys (3D aerial and terrestrial models): the archival drawings and images documenting previous events distressing the building, the previous strengthening intervention, and finally the seismic site response analysis (from Amatrice’s accelerometric station). Through a back analysis carried out by a finite elements model, it was possible to understand the seismic vulnerability of this historical building, in relation to the previous interventions and damage events. The proposed methodology, based on the interdisciplinary data analysis, provides useful information for the next strengthening projects of damaged historical monument.  相似文献   

14.
刘迪 《东南文化》2016,(6):102-106
面对19世纪末中国空前的民族危机和剧遽社会变迁,张謇选择了"实业救国"、"教育救国"的道路。南通博物苑作为张謇教育事业的重要组成部分,是其教育救国思想的具体体现。张謇在南通博物苑创办过程中实现了资本的文化化和文化的资本化双重过程:一方面,将经济资本转化为文化资本;另一方面,又将文化资本转化为其象征资本的一部分,使其获得更大社会权力,从而能够按照自己的政治理想对地方社会进行塑造。张謇对于作为文化资本的南通博物苑的支配主要体现在三个方面:藏品内容及知识系统的构建、博物馆教育作用的树立及对参观者的规范。张謇对文化资本的支配表面上是其个人意志的体现,由其政治理念所驱动;而深究,终不免受时代和机构属性等因素的制约与影响。  相似文献   

15.
The computation of Moran's index of spatial autocorrelation requires the definition of a spatial weighting matrix. The eigendecomposition of this doubly centered matrix (i.e., one that forces the sums of all rows and columns to equal zero) has interesting properties that have been exploited in various contexts: distribution properties of the Moran coefficient (MC), spatial filtering in linear models, generalized linear models, and multivariate analysis. In this article, this eigendecomposition is used to propose a new view of MC based on its interpretation in the simple context of linear regression. I use this interpretation to demonstrate the different properties of MC and also the inefficiency of this index in some situations involving simultaneous positive and negative spatial autocorrelation. I propose some new statistics and procedures for testing spatial autocorrelation, and conduct a simulation study to evaluate these new approaches.  相似文献   

16.
Traditional timber frame walls are constructive elements representative of different timber frame buildings, well known as efficient seismic-resistant structures. They were adopted as a seismic-resistant solution in Lisbon’s reconstruction after the 1755 earthquake. To preserve these structures, a better knowledge of their seismic behavior is important and can give indications about possible retrofitting techniques. This article provides a study on possible retrofitting techniques adopting traditional solutions (bolts and steel plates). Static cyclic tests were performed on retrofitted traditional timber frame walls. The experimental results showed the overall good seismic performance of steel plates and the more ductile behavior of bolts retrofitting.  相似文献   

17.
The Basilica of San Francesco in Assisi endured stronger earthquakes for centuries before 1997 earthquake, which generated the collapse of the two vaults. Experts blame as possible reasons of collapse the damage cumulated from previous earthquakes and/or the retrofitting made to the structure over its lifetime. This article presents the history of the retrofit interventions of the Basilica through the centuries, focusing mainly on the roof, which has been subjected to three major restorations through its life. It is shown using simple analytical models that the cumulative effects of the changes made to the roof of the Basilica affected the structure’s dynamic behavior in a negative manner, increasing the seismic loads on the existing structural members. In particular, the numerical results show that the 1958 roof intervention has stiffened the structure, redistributing the seismic loads on the façade and the transept. This overload might explain the collapse of the two Gothic vaults during 1997 earthquake.  相似文献   

18.
Shake table tests were carried out on a 7 m × 5 m three-story, timber light-frame building (7.5 m height) at the TreesLab laboratory (Eucentre) in Pavia. The aim of the research was to evaluate the seismic behavior of a typical Italian prefabricated timber building and to study the interaction between the individual structural components tested in quasi-static manner in a previous experimental study. The 1979 Montenegro Earthquake ground motion, recorded at the Ulcinj-Hotel Albatros station, was selected as the ground motion for seismic tests. The maximum peak ground acceleration was scaled to 0.07 g, 0.27 g, 0.5 g. 0.7 g, and 1 g in order to evaluate the building’s performance at different levels of seismic input. More than 100 instruments were used to monitor the behavior of the building during seismic tests measuring acceleration, displacement, and forces. The visual inspection shows that the building did not show any damage during all seismic tests. However the data analysis (dynamic identification, capacity spectrum, inter-story drift) confirm that during the 1.00 g test the structure went beyond its linear elastic limit. The results obtained from this experimental study suggest that the design hypotheses commonly adopted in practice for seismic analysis (e.g., in terms of force distributions between the walls, and also the behavior factor q) are not always consistent with the real behavior of timber frame multi-story buildings, and should be backed by more accurate knowledge of the contributions of the individual structural components.  相似文献   

19.
Mental Images: Towards a Media History of the Psyche around 1900. Presupposing that visual practices are inherent to the social constitution of knowledge, this article suggests juxtaposing photographs and films produced in a psychiatric environment to popular films run in theaters around 1900, thus identifying cinema’s particular “Denkstil” (Fleck). Rejecting science’s dominating paradigm of visual objectivity (Daston/Galison), the visual apparatus [dispositif] of early cinema facilitates subjective experience of unreason and irrationality and thus initiates a different epistemological approach to knowledge as self-knowledge of a modern, self-reflexive subject. This is particularly evident in early cinema’s depiction of the psyche, which does not solely focus on the physical manifestation of the ‘mad’, ‘insane’ body, but also visualizes the subject’s inner life: technical means like montage, multiple exposure or stop motion can be employed to illustrate subjective visions, fantasies or dreams. Thus, the invisible mind becomes visible as the “unthinkable within thinking” (Deleuze), while the subject is invited to participate in cinema’s “gay science” (Nietzsche).  相似文献   

20.
Prompted by contemporary concerns in the West over a global vision of nature and society at risk, this paper builds on recent studies of expertise within a broader public culture. By focusing on earlier episodes of social and political uncertainty, the paper argues that there is scope to extend such analysis in terms of historical geographies of specialist knowledge. The paper examines the formative years of British ecology, a discipline which from its beginnings in the wake of urban industrialism more than a century ago, was centrally concerned with the relations of human well-being and the environment. In exploring when, where and how an ecological expertise became defined, it shifts the focus from familiar milestones in the discipline's public recognition. By tracing the discursive and material practices of those who sought to identify and define ecology as a specialism, the paper illustrates the importance of groupings within and beyond accredited expertise in giving it meaning and purpose. In doing so it highlights the fragility and fluidity of the boundaries around ‘expertise’, and the significance of geographical context and connections in shaping its conduct and content. In terms of broader historical geographies, the paper suggests that while ‘expert’ cultures may be projected as giving greater public reassurance, the sense of certainty that this implies disguises complex processes in which the boundaries are imprecise between specialist and lay knowledge and between scientific and public spaces.  相似文献   

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