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71.
Three different lithotype groups have been recognized in representative fragments of pietra ollare artefacts found in the mediaeval archaeological excavations of Comacchio (Italy). Petrographic, mineralogical and chemical compositions clearly show that Valchiavenna and Valmalenco, in the Central Alps, represent the provenance areas of two of the pietra ollare groups, i.e. grey carbonate talc schist (also known as soapstone) and green chlorite schist, respectively. The third representative pietra ollare group consists of whitish-yellowish rocks inferred to be Alpine talc schists that have suffered some artificial pyrometamorphic transformation hindering their classification in the framework of pietra ollare lithotype categories and source localities reported in literature. A distinguishing feature of these high temperature-fired (HT-fired) talc schist samples is the occurrence of talc and chlorite dehydroxylation and subsolidus reaction products, mainly protoenstatite/enstatite + forsterite, together with relatively low loss on ignition values. These talc schists might have been exposed to temperatures >900 °C (with the resulting talc dehydroxylation producing a void-rich texture), but never reaching 1200 °C, which is the sintering temperature for soapstones. The whitish-yellowish artefacts were definitely not used as containers for cooking food at temperatures below or around 500–600 °C (as instead shown by the preservation of the original physical features of the grey pietra ollare lithotypes), but in some kind of higher-T pyrotechnological processes.  相似文献   
72.
This paper proposes an empirical climate classification method based on the application of multivariate statistics. In this method, the technique of supervised and unsupervised image classification is used to classify the data and define climatic units. envi software is used to perform the image classification, specifically, the Iterative Self‐Organizing Data Analysis Technique algorithm. Supervised classification is also applied based on reference variables, fundamental parameters and a classifier. The obtained results display greater objectivity, reliability, operability, accessibility and reproducibility than previous climate classifications devised for the region of Andalusia (Spain), taking into account that these previous classifications were not based on quantitative criteria.  相似文献   
73.
After the outbreak of war, public and private institutions in Italy embarked on various propaganda projects without coordination. It was not until Vittorio Emanuele Orlando became prime minister (from 30 October 1917 to 23 June 1919) that the first serious efforts were made to organize propaganda abroad. G. A. Borgese, a contributor to the Corriere della Sera, took an active role in the defense of Italian intervention in the war and was assigned various missions abroad, commissioned by the editor of the newspaper and, after this first experience, by the army and naval authorities, and by Orlando himself. His unpublished report Dello spirito pubblico in Francia, written at the end of his mission to Paris in March and April 1917, describes Italian propaganda efforts in France and French public opinion on Italy and the Italians, making it an important text that reveals both the problematic relations between Italy and France and the mistakes and shortcomings of Italian propaganda.  相似文献   
74.
This paper focuses on early medieval funerary practices from a landscape perspective in central Iberia. Rock‐dug graves constitute the most conspicuous remains in this region, but their informative potential has not yet been realized. The preliminary outcomes of an ongoing research project are presented here. This aims to contextualize such funerary cases by examining a mid‐altitude mountain study‐area. Through the use of intensive archaeological surveying and geographic information systems, the paper characterizes two basic funerary types: isolated graves and rural disordered cemeteries, which responded to two social strategies led by local households. By recalling ancestorship, they constituted effective mnemonic resources, contributing to claiming rights and forging identities among these dispersed and predominantly small‐scale herding communities.  相似文献   
75.
This paper puts forward the new analytical framework of ‘Digitally Mediated Iconoclasm’ (DMI) to analyse and interpret iconoclastic acts that are experienced through the propaganda (videos, social media, photographs, and other media) that the actor perpetrating the destruction makes available in global information networks for its consumption, duplication, and distribution. DMI captures three stages of the destruction (before, during and after the event) as both evidence of that destruction and as a perdurable digital archive. To demonstrate the relevance of DMI, we focus on an analysis of the videos and photographs depicting heritage destruction at pre-monotheistic sites targeted by the Islamic State (IS), such as Palmyra in Syria, the Mosul Cultural Museum, Nineveh and Nimrud in Iraq. The analysis focuses on the three stages that DMI comprises, showing the different photographic and audio-visual production techniques that the IS uses to enhance the tension that is built up leading to the destruction of cultural heritage while allocating material and human resources to produce digital propaganda. This analysis demonstrates how the analytical framework of DMI can be used to advance important work in heritage and media studies.  相似文献   
76.
ABSTRACT

Historical centers are always composed of masonry building aggregates often designed without respecting seismic design criteria. The current seismic Italian code does not foresee a clear calculation method to predict their static nonlinear behavior. For this reason, in this article the seismic response of structural units into masonry aggregates has been predicted through a simplified modeling approach. The implemented procedure has been calibrated on the results of a numerical model performed by using the Equivalent Frame Method (EFM), implemented within a Finite Element Method (FEM) calculation program, used to investigate a basic building compound representative of the constructive techniques developed in the past decades in the Southern Italy.

First, the whole aggregate has been modeled and analyzed in the nonlinear static field in order to evaluate the seismic behavior of both intermediate and head structural units.

Later on, the seismic response of these structural units, considered as isolated structures, has been assessed by considering in simplified way their position in the aggregate, as well as the influence of other constructions.

Finally, the achieved results on the above single analysis cases have been compared with those deriving from the investigation of the whole building compound, allowing to confirm the effectiveness of the proposed novel analysis procedure.  相似文献   
77.
The aim of this paper is to describe the creation of a method to apply digital image treatment, consisting of a combination of filters and algorhythms, to prehistoric rock carvings, to enhance the information obtained from them. In the experimental phase a study was made of a laboratory piece and two highly valuable pieces of cave art from the Tamanart Valley in Morocco and the Casares Cave in Guadalajara, Spain. The results clearly demonstrate the potential of the proposed digital methodas information was obtained that could not have been achieved by the traditional techniques.  相似文献   
78.
ABSTRACT. The least upper bound to the overall percentage error resulting from the omission of interregional feedbacks in input-output analysis is defined. This limiting value is the most informative of all upper bounds. A procedure for its computation is outlined and a number of experiments, using U.S. data, are discussed.  相似文献   
79.
80.
The study of material culture generated by military engagements has created an emergent sub-discipline of archaeological studies centred on battlefields. This approach has developed a particular and sophisticated methodology that is able to deal with the fact that archaeologists will often not find either structures or a useful stratigraphical record on the site, as the material remains of the battle will basically be metallic objects carried by combatants. It is therefore rather complicated not only to test hypotheses about battle events based on archaeological data, but also to validate the methodology used. Here we propose the use of agent-based models to explore these issues in the case of eighteenth-century battlefield archaeology. The simulation is divided into four different steps. Firstly, a battle is simulated in order to generate realistic virtual archaeological remains left by an engagement between two armies of this era. We then simulate the loss of information that the passing of time produces in the battlefield. The third step involves simulating the archaeological survey, enabling us to explore different survey strategies and the impact on the interpretation of the event itself. Finally, we design a confidence index in order to compare the results of the different virtual excavations using spatial analysis and statistics. The results show that the methodology is fully functional in terms of understanding a battle, and it allows us to suggest new strategies to improve fieldwork and to develop new ways of exploring these particular archaeological sites. It is concluded that the described approach illustrates how simulation can be used to explore methodological issues of archaeological science.  相似文献   
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