首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 406 毫秒
1.
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   

2.
Historical plasters on light thin vaults, usually made by mats of reeds nailed to an upper wooden framework, were used in several historical and monumental Italian buildings and churches built between the 16th and the 19th century and almost all of the historical Italian theatres built between the 18th and the 19th century to cover the theatre-hall and to improve its acoustic properties. The non-destructive inspection of these structures is very important, but traditional inspection techniques are usually limited in resolution, which may be a problem for detection of defects at a very early stage. The paper presents the development and application of a high-resolution inspection technique based on a hybrid ultrasonic method, where a contact emitter probe and a non-contact air-coupled receiver probe are used. Results show the effectiveness of the method on laboratory samples and propose an inspection procedure for in-field application.  相似文献   

3.
Restoring cultural heritage is an extremely important job due to its immeasurable value. However, it also requires even greater attention in the case of a building. The actions taken on these constructions not only guarantee their preservation from the point of view of their historical value, but they also guarantee their stability as structures. The need to control historic buildings, analyzing their defects and their possible consequences, is decisive in preventing significant damage. This work demonstrates calculating the thickness of vaults in a church. It is easy to determine the interior and exterior 3D geometry of the church using scanner laser techniques. By combining both geometries, it is easy to determine the difference between the interior vaults and the roof of the church. However, the interior of both geometries is completely unknown, and it is not possible to act on their condition for structural consolidation purposes. This work shows the methods used to determine the interior sections of the vault thicknesses by referencing the internal geometry of both models with the interior of the church, using plumb line system scanning. The results obtained show accuracy better than 6 millimeters.  相似文献   

4.
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   

5.
The critical condition of detaching historical murals in the Convent of Müstair (Switzerland) prompted a series of investigations and conservation actions over the last 40 years. After percussion tests in 1984/1992, an advanced technology of time-average TV-holography has been applied in 2000 and 2005. The primary aim was to substantiate if and to which extent detaching is in progress. This case study explores characteristics and limits of traditional percussion tests and time-average TV-holography. Extensive mappings by both techniques are carried out on two different structures of wall paintings. The comparison shows that the so-called percussion test – when combined with a close experienced observation – reveals a holistic picture of the general condition of a threatened painting. Time-average TV-holography, on the other hand, yields highly accurate relative information on the spatial distribution of detached areas. Therefore, it is apt to provide an exact answer to the question if detachment is in progress or not.  相似文献   

6.
  相似文献   

7.
This paper describes the ground-penetrating radar (GPR) survey carried out on the Roman theatre of Sagunto (Valencia, Spain) following recent restoration work in 1991. The structure has been substantially altered a number of times: it was remodelled during the Roman and Moorish periods, partially destroyed during the Peninsular War (1808–1814) and the Carlist War (1833–1839), and extensively modified during the 1930s and 1950s. Major reconstruction work was carried out in 1991 to convert the building into a working theatre. The GPR survey was performed to detect the possible effects of the 1991 remodelling on the historical remains and to identify the point of contact between the present-day modifications and the Roman remains. We took several on-site measurements of the wave velocity in the different materials in known areas to determine as accurately as possible the depth of the contact point. The velocity was calculated by measuring the depth in these areas and the two-way travel time of the wave. The measurements were taken from the walls and the tiers as the thicknesses of the materials were known in these areas. The recorded values were compared with the velocities reported by other authors and with the information from diffraction hyperbolas recorded in the radar data, which are caused by small objects inserted in the medium. We used these velocities to determine the exact point of contact between the Roman remains and the materials used in later restorations. The contact points cause the reflections that can be seen in the GPR data. The results also reveal considerable variations in the surface of the Roman tiers, which can be attributed to partial erosion in these areas caused mainly by water.  相似文献   

8.
Rural buildings have undergone deep changes with the historical transition from traditional agriculture to industrial society. This paper discusses these trends in Italy, focusing on major changes in agriculture, design approach, and land-use planning, referring to some regional cases and relative building typologies. The analysis of the main historical treatises on the subject of farm building design allowed us to evaluate how the evolution of the technical approach influenced the architectural quality of rural buildings. This latter was traditionally based on a close relation between aesthetic values, functionality, and simplicity, broadly acknowledged only recently, as shown by the loss of landscape integration of farm buildings constructed in the last decades. By analysing the processes of reuse of historical buildings and construction of new farm buildings, we have found out different and time-evolving ways of referring to rural heritage and identity. In some cases, they have been considered important references, even through typological evolution aimed at combining traditional values with new needs and available techniques. In other cases, old farm buildings have been considered unsuitable things of the past, or rather have inspired new constructions based on an idealized and mystified concept of rurality. Since landscape integration of rural buildings plays a crucial role in the EU concept of agriculture, the choice of architectural quality postulates to be adopted for the design of new rural buildings is a key theme. Both consistency with pre-industrial tradition and typological discontinuity must necessarily consider consciously the relationships with historical buildings, whose important values have increasingly come to the fore over the last years. Once consistency with historical farm buildings is assumed as a design postulate, contemporary interpretation of traditional typologies through modern building techniques is a very challenging and topical field of study. Various degrees of consistency with traditional typologies are possible. Therefore, this approach calls for the development of analytic and metadesign methods aimed at decomposing rural building typologies into their essential physiognomical features, allowing designers to modulate them to meet ever-changing requirements.  相似文献   

9.
The use of remote sensing techniques for the monitoring of historical buildings is attractive, since it can allow a fast monitoring of large surfaces without the use of scaffolding and, in addition, a thematic mapping which is easier to read. The studies on fluorescence lidar monitoring of buildings started a few years ago and are still in progress. Interesting results were obtained in biodeteriogen monitoring and in the identification of stones. The possibility of detecting fluorescence thematic images of large areas was demonstrated on both artificial targets and historical buildings. This paper describes the current state of the art on fluorescence lidar monitoring of buildings and the research trends for the near future.  相似文献   

10.
Historical cartography all over the world is a fundamental part of Cultural Heritage, and it needs to be preserved from damage of its analogical support due to ageing. Regeneration of ancient cartography in digital form is an interesting way not only to preserve historical cartographic documents as Cultural Heritage, but also to allow new chances of understanding and using the historical information they record. In such a way, modern digital techniques, in particular study of map deformations and map georeferencing, help in metric analysis of ancient cartography, and at last they appear to be useful for researchers to derive historical information for their studies, for example related to urban development or to geomorphological and environmental topics. The present research would give an example of the usefulness of the digital regeneration of ancient cartography, but also an example of possible difficulties in correctly interpreting information preserved in historical cartography, especially the pre-geodetic one. The study subject consists in three contemporaneous pre-geodetic maps (late 16th century) from the ancient Po river delta area (Italy), by means of which a geometrically correct representation of those parts of the landscape, not preserved today because of sea erosion, was tried. In fact, standard georeferencing methods, that use reference control points to compare historical cartography with the present one, in this specific case demonstrated to be not successful in describing the real location of disappeared landscape details with an adequate level of accuracy. For these reasons, in order to define which map among the others was the most faithful to the contemporaneous physical reality, a compound methodology, consisting of a three-step analytical process, is here applied to the three samples. Starting from measurement of sighting angles and distances applied to a number of landmarks, a splitting of the old maps in sub-areas, probably corresponding to the set of original surveyed zones, was performed. In the area of main concern, the use of absolute measurements was avoided in order to check the level of inner congruence of the representation. Finally, a new specific error index, that can also be applied to maps lacking an explicit graphical scale, is proposed to evaluate the map truthfulness degree. The proposed method can be applied to other similar examples from ancient cartography.  相似文献   

11.
As part of a working definition of a new code of practice, this paper develops a methodology to determine the suitability of plasters manufactured on-site to protect the earthen walls of vernacular architecture buildings. Given the diversity of raw earth construction types, ranging from massive earth to stone masonry with earth mortars, and the variability of the materials used, two on-site tests (a shrinkage test followed by a shear test) were proposed. Those tests, as well as additional tests, were performed with lime/sand, earth/sand and earth with plaster admixtures. Lime/sand plasters do not typically pose shrinkage issues, which is why more earth based specimens were tested than lime based specimens. An analysis of the on-site testing complemented with laboratory tests reveals an antagonistic control of the bond between earth plaster and earthen wall based on clay content: an increase in the plaster clay content leads to increased bending strength, which strengthens the plaster and increased shrinkage, which weakens the plaster-wall interface. The heterogeneity of the wall leads to a wide range of results; therefore, this study was conducted to validate the formulation of plasters by means of shrinkage and shear tests at five different points on the wall. The shrinkage test allows finding the earth plaster formulations. Among all the validated formulations, the mason chooses the best one thanks to two criteria: the best workability (which is variable according to masons) with the highest clay content as possible. Then, when the formulation is chosen, the shear test must be done to verify if the bond between the plaster and the wall is high enough. This series of tests allows masons to validate formulations that will ensure good mechanical resistance of the plasters that protect buildings of vernacular earthen architecture.  相似文献   

12.
Boris Hauray 《Minerva》2017,55(2):187-208
Medicines regulators have generally adopted a scientistic view of medicines evaluation, which they present as an exercise that should—and indeed can—be purely “objective,” based only on knowledge produced through validated research protocols. The growing body of social science literature analyzing the regulation of medicines has questioned this pretense of objectivity and underlined the socio-political construction of evidence on the risks and benefits of medicines. But while the European Medicines Agency has become the dominant regulatory body in Europe and a key player at world level, very few studies have investigated its actual practices. Based on interviews with European regulators, but also on direct observations of several meetings of the European Medicines Agency’s main expert committee, this article aims to analyze how regulatory knowledge is defined and then transformed into regulatory decisions. First, it describes the main characteristics of European medicines regulation and the historical definition of what can count as “objective” evidence on the safety and efficacy of medicines. Second, it demonstrates that experts use many different types of knowledge in building their opinions: the results of studies, but also knowledge about firms’ past and present strategies, about patients’ needs and future behavior, about the state of research and clinical practices, and about legal and policy-making issues. Third, it explains why, in spite of the various forms of knowledge involved, experts manage to produce consensual opinions on medicines and why these opinions are considered genuine decisions in the sector.  相似文献   

13.
Budget constraints at the local government level towards the provision of public goods have fuelled interest in the voluntary contribution and provision point mechanisms. However, due to their public nature, these mechanisms are not without problems. The literature shows the presence of free riding and socially inefficient contribution levels. This paper experimentally tests the effect of cultural and historical information pertaining to heritage houses in Penang, Malaysia, on public contributions for their conservation. This paper considers a standard linear one-shot four-person public good game and the decision of the subjects being to contribute either to a private or to a public account. We devise 4 treatments: a Control treatment, a treatment where subjects are provided with cultural and historical information pertaining to the heritage houses, a treatment that includes a contribution threshold, and finally a treatment that combines the use of cultural and historical information with the contribution threshold. The main finding shows that 60–75 % of the subjects contributed more than what they believed others in the same group would contribute when they were provided with the pertinent cultural and historical information. Most of the subjects contributed less than their belief, while 75–77 % cooperated ‘selfishly’ in treatments without the information. These findings are in agreement with the literature, namely that contributions are higher in treatments with a contribution threshold. Moreover, the combination of a contribution threshold and cultural information could encourage more pro-social behaviours.  相似文献   

14.
通过多个历史文化名城的相关保护规划文本、地方保护条例(办法)以及地方规划编制技术导则的分析,对历史文化风貌区的地方实践进行总结。"历史文化风貌区"较历史文化街区具有更丰富内涵与复杂性特征,保护规划过程中应注意识别"历史文化风貌区"中出现的新类型与内部价值要素,在探索和完善地方历史文化遗产保护体系的前提下,秉承不同于历史文化街区的保护思路,探索差异化的、量体裁衣式的历史文化风貌区保护方法。  相似文献   

15.
Assessment of multi-leaf stone masonry in earthquake-prone areas is mostly related to the evaluation of its texture, morphology, leaf detachment and structural cracking due to previous seismic activity, as well as disintegration due to material deterioration. For the plastered masonry with heritage or artistic value (paintings, frescoes etc.), both the type of structure and the extent of damage should be characterized with minimal interference to the structure, which could be overcome solely by non-destructive testing (NDT). However, due to the complexity of plastered multi-leaf masonry structure, the performance of well-known NDT methods could be significantly worsened. Therefore, as a prerequisite for applying NDT on multi-leaf stone masonry in practice, a validation process should be carried out. In this study, complementary ground penetrating radar (GPR) and infrared (IR) thermography measurements on plastered laboratory three-leaf stone masonry walls were performed. Apart from assessing the wall texture and morphology with the type of connection between the leaves, detection of gradual plaster delamination and crack propagation while subjecting the walls to an in-plane cyclic shear test was taken into account. The results showed that GPR could successfully visualize header stones passing through the whole depth of the specimen. The masonry texture behind the plaster could be well resolved by both methods, although GPR near-field effects worsened its localisation. For the detection of plaster delamination, IR thermography outperformed GPR by detecting delamination as small as 2 mm as well as structural crack patterns, whereas GPR only detected delamination larger than 8 mm. It was shown that the performance of both methods for defect detection could be further improved by image fusion based on unsupervised clustering methods.  相似文献   

16.
Plasterwork, a very typical element of Islamic art, comprises highly artistic decorative elements on wall, arches, and vaults. Due to their gypsum composition, such elements are easily weathered, primarily because of low mechanical strength and slight solubility in water. This work has studied the traditional Islamic plasterwork in the halls and patios of the Mudéjar Palace (13–16th centuries) in the Real Alcázar of Seville. This palace complex was declared a World Heritage Site by UNESCO in 1987. The analysis of its porosity and shore C surface hardness has allowed determination of the mathematical correlation between them. Consequently, future evaluations can merely measure the hardness (a non-destructive test) to estimate the plasterwork's porosity (which reveals its mechanical strength and its degree of weathering). These elements must be maintained in order to prevent the spread of pathologies. In addition to requiring an in-depth knowledge of its materials, application techniques, and properties, to do so also demands simple techniques for regular assessments and criteria to prioritize interventions if they become necessary.  相似文献   

17.
Balmer B 《Minerva》2002,40(1):57-75
This article presents historical cases in which Britishscientists, principally scientific advisors, have attempted to defendresearch on biological weapons. Although the historical record is scant,there is a degree of continuity in their justifications, and a number ofthemes can be identified. It was argued, that biological weaponsresearch is morally justified because it produces humane weapons; thatit is no different from medical or other research; and that it is beingperformed for defensive purposes. It is argued that this defence isdirected primarily towards other scientists working on germ warfare, andwas formed part of the `moral economy' of that secretcommunity.  相似文献   

18.
This essay examines an aspect of the historical trajectory of Papua New Guinea's creole language Tok Pisin. A medium key to colonisation, pacification, and nationalisation, Tok Pisin's fortunes as a ‘real’ language in popular perception can be tracked through the orthographic choices that have clarified or obscured the etymological connections to the colonial, English-language past. Scholarly approaches to Tok Pisin and other creole languages have concentrated on the orthographic reflection of the regularities of structure that index ‘full’ languaged-ness and modern national autonomy. In contrast to this project of linguistic nationalisation, contemporary Tok Pisin speakers are developing repertoires of speaking/writing that invoke Tok Pisin's connections to Australian English even as they do not conform to it, an enregisterment of forms obscuring the boundaries between Standard English and Tok Pisin. As a convention used by youth in SMS and similar contexts, this practice subverts a prior generation's language ideology by pairing the lateral connections of new media with a repudiation of creole orderedness.  相似文献   

19.
Academic treatments of distributive justice normally adopt a static approach centred on resource allocation among a set of individual agents. The resulting models, expressed in mathematical language, make no allowance for culture, as they never engage with the society's way of life or the moulding of individuals within society. This paper compares the static approach to distributive justice with a cultural one, arguing that a case for redistribution should rest upon its cultural effects in assisting well-being and social cohesion. Unless we recognise culture, we can have little understanding of why inequalities matter, where they come from, and how they might be reduced. Redistribution may be motivated by universal value judgements taken from external sources, but it also entails internal cultural changes that refashion social relations through cumulative causation. In practical terms, it has to penetrate beyond reallocating resource endowments to bring revised attitudes in a society less tolerant of unequal outcomes. Egalitarian reforms will flourish only if they generate and reflect an egalitarian culture.  相似文献   

20.
The present research is an attempt to create a link among different disciplines and to confirm stratigraphic observations through chemical analyses. It involved detailed colorimetric examination and in-depth chemical-physical study of the samples taken from the historical centre of Genoa, which enabled connections to be made among many data. This led to the creation of an analytical method that is applicable to various geographical sites. Examinations involved several experimental techniques: X-ray diffractometry, scanning electron microscopy, optical microscopy and infrared spectroscopy; the data were compared with those from the stratigraphic examination. A detailed investigation of the Ligurian climate, including data kindly supplied by the Environment Department of the Provincia di Genova, allowed us to explain the presence of particular chemical substances and suggested how they might have been formed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号