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1.
Computer tomography (CT) technology has greatly contributed to the feasibility and convenience of detecting and visualizing the internal material constitution and geometrical fabrication of museum artifacts. This paper presents a case study of 3D virtual reconstruction for the CT-acquisition-based study of a cultural heritage artifact. It documents the complete procedure, including the preprocessing, segmentation and visualization of the data by providing coarse interactive exploration and integrated high-quality renderings. A parallel aim achieved was to use open source tools and free software for segmentation and visualization, thus providing full transparency of the adopted methodology and 3D visualization methods, and a cost effective solution for ordinary CPU-based PC users. Furthermore, the challenges of the large data volumes involved have been addressed using preprocessing, a segmentation scheme and linked front-to-back management to keep interaction and high-quality rendering available, thus achieving corresponding demands.  相似文献   

2.
Several new tools to obtain three-dimensional information from unorganized image sets are now available for the public use. The main advantage of this software, which is based on dense stereo matching, is the possibility to generate 3D content without the need of high-cost hardware (e.g. 3D scanning devices). Nevertheless, their use in real-world application domains (like cultural heritage) is still not very diffused, due to the non-straightforward usability of the raw data produced. In this paper, we investigate the use of automatic dense stereo reconstruction tools for the monitoring of an excavation site. A methodology for the effective acquisition and processing of data is presented. In addition, the results of the data assessment demonstrate the repeatability of the data acquisition process, which is a key factor when qualitative analysis is performed. The use of three-dimensional data is integrated in an open source mesh processing tool, thus showing that a spatio-temporal analysis can be performed in a very intuitive way using off-the-shelf or free/open digital tools. Moreover, the use of peculiar rendering and the creation of snapshots from arbitrary points of view increase the amount of documentation data, and suggest a perfect integration of data produced with dense stereo matching in the future standard documentation for excavation monitoring.  相似文献   

3.
Taubert  Niels 《Minerva》2021,59(2):173-194
Minerva - Open access (OA) to publications has become a major topic in science policy. However, electronic publication providing free access to research via the internet is more than a decade...  相似文献   

4.
Hyperspectral data were exploited to test their effectiveness as a tool for archaeological prospection, envisaging their potential for detecting spectral anomalies related to buried archaeological structures. For this purpose the airborne Multispectral Infrared and Visible Imaging Spectrometer images were analysed. Each single band of the entire data set and different processing technique products were interpreted to identify any tonal anomalies. Since every analysed image exhibited marks different in terms of size and intensity, two indexes were defined for assessing the potential of anomalies detection of each image. Such parameters were: the Detection Index, used for counting the number of pixels related in each image to marks, and the Separability Index, applied for measuring the tonal difference of the marks with respect to the background. These indexes were tested on two areas within the Selinunte Archaeological Park where the presence of remains, not yet excavated, was supposed by archaeologists. For the test sites any extracted anomalies were evaluated by an expert in order to determine their archaeological relevance. The comparison among the index values, derived from each single band of the spectrometer and from different image processing by-products, allowed to determine which spectral range and which processing method are the most valuable to quickly highlight the anomalies. The analysis pointed out that, where vegetation cover is dominant, the Visible near infrared is the spectral region more sensitive to variations of spectral properties related to buried structures, while, where soil cover becomes relevant, the Short-wave infrared and the Thermal-infrared regions resulted more sensitive. As far as the applied processing methods are concerned, the Spectral Angle Mapper classifier and, secondly, the Minimum Distance algorithm stressed the highest archaeological information content. The results of this work showed that the archaeological information content derived by analysing the outputs of the applied image processing techniques is more significant than the information obtained by interpreting each single band and the available historical aerial photos. As a final remark, the data processing flow chart, applied to the entire remote hyperspectral data set over Selinunte Archaeological Park, appeared encouraging for detection of anomalies related to the presence of the buried archaeological structures.  相似文献   

5.
Money is an ‘instrument of collective memory’ before it is a means of exchange, a unit of account or a store of value. Money's status as a memory technology is particularly significant in light of the role that information and communication technologies now play in economic transactions. Many of the new channels and infrastructures for payments, such as magnetic cards, mobile phones, the wired Internet, social media platforms, and RFID technologies, record detailed transactional data alongside a range of other identifying data. We now have extremely detailed records of the many ways that money circulates, is transferred and is spent. This paper concerns this previously latent transactional data and how it is currently recorded, monetised, and used to inform action. What has been recorded in and about money at different moments in time and how are these categories breaking down? Who has access to and ownership over this collectively produced record and how is it driving new data practices and business models based on the monetisation and application of monetary records? And how might re-engaging with money's mnemonic status help to foreground a politics and ethics of transactional data?  相似文献   

6.
Reputations of organizations and its individual members are valuable resources that help new organizations to get access to investment capital. Reputations, however, can have different dimensions. In this paper, we argue that an individual??s reputation along a particular dimension will have a positive effect on the behavior of investors when it is role congruent. In addition, we argue that also scoring favorably on the role-incongruent dimension at the same time??or, in other words, engaging in reputational category spanning??will weaken the positive effect of the role-congruent reputation. Our empirical setting is the film industry where we study the effect of the two main dimensions of reputation in cultural industries, artistic and commercial, of both directors and producers on the size of the investment by distributors. In this study, artistic reputation is based on professional critics?? reviews and commercial reputation on box office performance of the films in which individuals were involved in the past. We find that the commercial reputation of a film producer based on past box office performance has a positive effect on the size of the investment by film distributors. In addition, we find that directors who at the same time combine both a favorable commercial as well as an artistic reputation actually receive a lower investment from film distributors.  相似文献   

7.
The evolution of real time 3D graphics technologies in combination with high bandwidth Internet connections and modern Web browsers enable users to explore complex 3D scenes. As a rule, a virtual visitor has to manually explore the geometrically complex 3D model in order to discover points of interest. This manual exploration is a time consuming process that, in some cases, can be assisted by sets of predefined points of interest. In this paper, we propose the annotation of 3D scenes in order to equip the user with a text based 3D scene search engine. The search engine provides a query mechanism that unburdens the user from the time consuming process of manually exploring vast 3D scenes. It responds to queries by exploiting the metadata of each 3D model and returns textual and visual information along with a group of links that correspond to relative points of interest within the 3D scene. The search engine allows the virtual visitor to automatically be transferred to a specific point of interest. We have built a Web accessible prototype system that is able to handle queries related to historical data, topological relationships and architectural properties of buildings. A number of 3D reconstructions covering urban areas of cultural importance located in Northern Greece have been annotated and used in the search engine as case studies. The prototype system is based on open source technologies and on a hybrid metadata schema that is derived from the MIDAS Heritage and MACE schemas.  相似文献   

8.
Theatres have a market bounded by the distance theatregoers are willing to travel to see shows and productions. This paper uses count data models (Poisson regression and negative binomial models) to investigate the determinants of attendance at a regional theatre in England. It uses booking data for 29 theatrical productions supplied by the theatre, and matches this, using postcodes, with census socio-economic information on household characteristics. Socio-economic and travel cost (distance) are used to explore theatregoers attendance, and also to estimate consumer surplus, and to assess whether consumer surplus on ticket sales exceeds the annual government subsidy to the theatre.  相似文献   

9.
In the present paper, we analyse the allocation process for cultural services in Norwegian municipalities. The cultural sector at this administrative level is decomposed into the following eight subcategories: children’s and youth activities, libraries, cinemas, museums, arts dissemination, cultural heritage, cultural schools, and other cultural services. By means of budget shares for these eight cultural services and a residual sector consisting of all other municipal services, we estimate a system of demand relations which are interdependently linked to each other by a budget restriction. Our analyses are based on data from 409 out of 429 Norwegian municipalities during the period 2002–2010. In the empirical analyses, we mainly focus on the effects of income variation for the cultural services. We estimate effects of free income, matching grants to each sector, and user fees and other sector-specific income for each sector. We also estimate crowding-out effects for the cultural sectors of demographic variables indicating higher demand for services such as education, childcare, and health services. Our results confirm previous results. There are interesting differences within the group of cultural services, and these are partly related to different levels of national standardisation and regulation among the cultural services.  相似文献   

10.
This work is part of a multidisciplinary research project, developed in collaboration with archaeologists and geophysical experts, which aims at delineating the spatio-temporal relationships between paleoenvironmental conditions of an alluvial plain in an alpine environment and the human settlements during past ages. The study area is located in the upper Lake Como region at the confluence of the Valtellina (Adda river) and Val Chiavenna (Mera River) valleys in northern Italy. The area is a deltaic zone which was affected by great adjustments due to varying sediment loads and separate parts emerged at different times, thus conditioning the human presence and distribution. Archaeological evidences dating back to the last millennium BC and relicts of Roman ages were discovered in the area, particularly during the 19th century Adda River canalisation. Remotely sensed images taken from space orbiting satellite at different wavelengths of the electromagnetic spectrum, from visible up to thermal infrared, were used to delineate landscape features not easily detected on ground. Geomorphological study of the area was improved by means of historical aerial b/w photographs taken before the Second World War by the Royal Air Force. Ground surveys and proximal sensing measurements, using portable spectral radiometers operating at the same wavelengths as the satellite sensors, were conducted at some experimental sites. Integrated analysis of remote sensing multilevel derived information, cartographic data and archaeological evidences proved to be useful for archaeological research with indications of favourable sites for future exploration in the area.  相似文献   

11.
Stephen Fortescue 《Minerva》1992,30(4):459-478
Conclusion Although the Russian Academy has not been operating long enough to permit a categorical statement that it will act exactly as the Soviet Academy did, there is now enough information to justify stating that in its structure and stated functions it differs in no significant way from the Soviet Academy which it replaced. While it might well have been weakened, through a decline in its own prestige and through the weakening of the government under which it operates, it is unlikely to be so weakened that it will allow either the democrats and rank-and-file research workers on the one hand, or the new bureaucratic arrangements on the other to get the better of it. While the desperate budgetary situation will almost certainly force the Russian Academy into considerable retrenchment in its research activities, it will continue to be a body of bureaucratically organised and experienced managers of science and will conduct itself accordingly. Those who believe that a high level of participation by the rank-and-file of the staff is essential in the management of science, will see that as a catastrophe for Russian science. Those who believe that particularly in times of stress, bureaucratic skill and experience are of great importance will see it as providing some hope of salvation.  相似文献   

12.
In the field of Cultural Heritage, image analysis represents an indispensable practice for restorers to collect information about the state of preservation of monuments and artifacts and plan restoration interventions. In addition, during the last two decades, the wide spread of remote sensing technologies and the possibility to build 3D reality-based models of artifacts allow the extension of image analysis to 3D environments. In this context, the purpose of this contribution is to show the results of investigations held in order to provide a methodology for the automatic detection of deteriorated areas within architectures and artifacts using colour images as a field of examination. Using both 2D and 3D segmentation approaches, our methodology aims at speeding and efficiently performing the automatic detection of deteriorated zones within Cultural Heritage and therefore segment 3D digital models acquired using different survey technologies. Within our investigations, we selected case studies concerning recurrent deteriorations, such as, for example, detachments, cracks and chromatic alterations; we run them both to manual and to automatic recognition and selection tests, in order to compare the results obtained using these approaches and evaluate the reliability of the automatic one. Results comparison included computational and user time, quantification of the deteriorated area error between manual and automatically detected zones. Additional parameters characterizing the specific type of deteriorations were also computed for each case study. Comparison between the automatic and the manual procedure showed that the automatic detection is faster and reliable in all our selected case studies, with evident improvements in the efficient evaluation of the entity and extension of deteriorated areas on 3D geometry.  相似文献   

13.
This study proposes a procedure for digitally classifying and cataloging moulds which belong to the historic collection of the Ginori porcelain factory in Doccia (Sesto Fiorentino, Italy). In addition to a vast number of antique plaster moulds, this collection includes artistic porcelain artifacts obtained from casting porcelain using the moulds and models made of various materials. The proposed methodology includes two workflows: the first starts with photographic and casting processes conducted recently on various groups of moulds and involves historical surveys for investigating the relationships between the various sets of moulds, the models from which they were derived and the porcelain objects derived from them. The second workflow was applied when no information was available for a set of moulds, and involved 3D scanning of the moulds, with virtual reconstruction of the corresponding model followed by a final art historical survey like that used in the first procedure. 3D scanning techniques and successive model reconstruction can also be applied for obtaining a virtual model in the first process, when the physical model was lost, damaged or never existed. The variety and extent of the Ginori collection suggested the use of a customized Data-Base (DB) and a set of functions designed to manage and extract information, data and archived images. This filing system, called DocciaDigitalArchive (DDA), also makes it possible to specify the relationships between the different typology samples (prototype models, moulds derived from them, handmade porcelain objects produced from these moulds), which are associated when the same subject is portrayed. The DB structure conceived also provides the possibility of incorporating pictures and data of known archetypes. This additional information makes it possible to place each subject in its historical and artistic context. For each sample filed in the DDA system, documentary cards, which summarize data, images, reports and links to other entities or samples connected to the subject consulted, can be viewed on a suitable interface.  相似文献   

14.
Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria.  相似文献   

15.
Three-dimensional (3D) digital preservation aims at generating 3D models of objects that have cultural or scientific value. It allows realistic visualization of objects through virtual museums or scientific applications, and the restoration of the preserved object in case of natural wear or accidents. This work contributes to this research area by presenting a method to improve color texture quality of 3D models obtained from color and depth images of a laser scanner. Although this device offers precise depth information, the resulting color information is still poor and limits the generation of realistic textures. Our approach is to capture photographs of the object with a high-resolution digital camera and use them to generate a new color texture for the 3D model. Our work proposes a practical technique, easy to replicate, to generate high quality textures for 3D models from photographs. The method is composed by three main steps: (1) calibration of the image acquisition devices; (2) data acquisition; and (3) texture generation. In this paper, we detail our color texture generation method and apply it on the digital preservation of many artworks made by native Brazilians (indians) from the Wauja and Karaja communities. These indigenous communities are acknowledged as great ceramic artists, each bearing their own main themes, using a very rich symbolism in their paintings. Their artworks represent important aspects of the native South American culture and their digital preservation is motivated by three main reasons: (1) their fragility; (2) the paintings loose their original appearance with time; and (3) the possibility of extinction of these communities. We present several results of preserved artworks with enhanced quality realistic texture maps. Also, we present a methodology to analyze the quality and accuracy of texture maps. The resulting 3D models can be visualized through a tool we developed to support the virtual exhibit of 3D preserved heritage.  相似文献   

16.
The Labour Government recently stated that access is a cornerstone of all its cultural policies, including those for museums and galleries. This paper therefore outlines a robust paradigm by means of which the impact of admission charges on access can be analysed. In applying that paradigm to museums, it demonstrates a number of analytical and theoretical red herrings which serve only to confuse a study of charges, including the zero marginal cost argument for free admission. Unless it uses this framework, the Government cannot be sure that it has secured access for the many instead of the few.  相似文献   

17.
In many historical and monumental Italian buildings, frescoes or stuccoes of artistic and historical value are present on the lower surface of flat light vaults, made by wooden arches, reeds and plaster. These vaults are often suspended by wooden or metallic ties to the upper bearing structures. When differential settlements of the wooden arches happen (i.e.: due to a bad working of their hangings) cracks appear on these precious surfaces. This paper experimentally and numerically investigates on this issue, pointing out which constructive parameters mainly influence the cracking behaviour of the frescoed or stuccoed lower surface, and thus providing guide lines for designing compatible conservation and retrofitting interventions.  相似文献   

18.
The electrical resistivity tomography (ERT) represents one of the widely used geophysical techniques for the exploration of the subsurface. In the last few years, this method has been demonstrated to be an efficient reconnaissance tool not only for monitoring degradation status of walls and foundations of historical buildings, but also for imaging the spatial distribution of injected mortar, commonly employed for consolidation purposes. A 3D resistivity tomography survey was carried out on four selected wall portions of the historical church of Montepetriolo, Perugia, Central Italy. The obtained 3D resistivity distribution models before and after grouting provided suggestive images of the internal structure of the studied walls. Moreover, the spatial distribution of the zones being filled with mortar was determined quantitatively by scaling the post- to the preinjection resistivity values. Using a well known correlation between resistivity and porosity, established in the geophysical community, a further step towards a more quantitative assessment was attempted to indirectly determine the unit volumes of the injected mortar The obtained results were satisfactory and in some cases almost similar to the yard data. Furthermore, two flat-jack tests confirmed the local increment of the mechanical resistance of the studied left front (2) and right lateral (3) wall portions.  相似文献   

19.
In this article, we examine how models working on Chaturbate, one of the world’s most popular adult webcam platforms, negotiate and make sense of the dynamic ways in which this platform configures their competitive environment. By combining different perspectives from the field of economic sociology, we demonstrate how competition on Chaturbate is shaped by various market devices whose strategic negotiation informs – and is informed by – the moral economy articulated on web forums where models gather to discuss their work experiences and market strategies. We first introduce Chaturbate and the ways in which it organizes market competition, surveying the environment models have to negotiate. We then zoom in on two controversial strategies for beating the competition, each of which upset the moral economy of Chaturbate’s model community. Subsequently, we turn to what models term ‘the hustle,’ which encompasses a number of competitive strategies and criteria judged to be fair and thus legitimate. The final part of our analysis considers the limitations of the hustle, as well as the meritocratic and entrepreneurial discourse that surround it, in light of what we identify as Chaturbate’s ‘manufactured uncertainty.’  相似文献   

20.
ABSTRACT

This paper uses ethnographic and archival data to analyze the creation and legitimation of predictions in industrial mineral exploration in Sweden. The search for exploitable ore deposits is a finance intensive process of resource creation in which mineral explorationists (e)valuate mineral deposits in order to assess their future minability. This paper builds on the recent literature on ‘imagined futures’ and futurework and combines it with the conceptual toolkit provided by (e)valuation research in order to outline how mineral explorationists establish a deposit’s existence and its future minability. Arguing that the creation of imagined futures plays an important role in mining and other social and economic phenomena, this article shows how imagined futures are created, and by whom, in the field of industrial mineral exploration, and how the creation of these futures is situated in a universe of actors’ beliefs, of valuation devices, and of norms and standards. The paper also shows how industrial standards guide this predictive enterprise and provides legitimacy to the results.  相似文献   

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