Preservation Of Cultural Relics Research Articles

Vulnerability assessment for physical protection systems of cave temples: A fuzzy petri net approach

Preservation of cultural relics is crucial for cultural sustainability, particularly in the case of cave temples, which are a unique and immovable part of our heritage, nested within mountains. These structures bear immense historical significance and possess considerable economic value, making them vulnerable to criminal activities, notably theft. Establishing a robust physical protection system (PPS) is imperative to safeguard these relics from potential damage. This paper proposes a novel approach for assessing the vulnerability of cave temples' PPS. Based on the fuzzy Petri net (FPN) principle, a comprehensive vulnerability assessment index system was developed within the PPS framework, considering the unique characteristics of cave temples. This study refines the formal definition of the FPN, enhancing its precision and effectiveness for vulnerability assessment. The practicality and effectiveness of the proposed method are verified through simulation experiments. An illustrative example is provided to demonstrate this approach.

Modelling and protection of grotto temples based on iterative closest point and Poisson

As a non-renewable cultural heritage, grotto temples face many value threats and the crises of rapid extinction. Due to the unique environment, diverse volume and complex geometric structure of grotto temples, cultural relic protection faces huge challenges. Digitisation has become the most important and effective preventive protection method. This study proposes a comprehensive modeling method, which uses three-dimensional (3D) laser scanning technology to obtain the point cloud data of grotto ruins, close range photogrammetry to obtain multi-angle and high-resolution two-dimensional (2D) image data, and through the fusion modelling of the laser point cloud and image dense matching point cloud, a complete geometric model of grotto is obtained. The registration method of the improved algorithm is based on Euclidean distance residual. The performance is better, with residuals mainly distributed in the range of 0.02 to 0.03 mm. In terms of texture mapping, the accuracy of model mapping is adjusted by adjusting the constraints of control points. The gray values of 50 pixels around the control points show significant gradient changes in the X direction, while the changes in the Y direction are relatively small. These methods and technologies provide practical and effective means for the protection and preservation of cultural relics in grotto temples.

Impact of Rock Matrix Seepage on Hollowing and Cracking of Surface Restoration Layer in the Leshan Giant Buddha

ABSTRACT The degradation of stone cultural heritage due to weathering has posed significant challenges in cultural relics preservation. This study focuses on the role of seepage in rock weathering and its effects on the interface between the rock matrix and the restoration layer of stone cultural relics. Specifically, a hydraulic-mechanical coupling model was developed for the rock-restoration layer interface of the Leshan Giant Buddha. The stress distribution and seepage characteristics in the rock matrix were analyzed, revealing the influence of seepage on interface stress, cracking, and hollowing of the restoration layer. The following conclusions are obtained through the research:Seepage at the interface between the rock matrix and the restoration layer leads to cracking and hollowing, creating obstacles in the protection of cultural relics; shear stress at the interface between the rock matrix and the restoration layer is the main cause of cracking in the repaired layer; uneven distribution of bonding strength between the repaired layer and the bedrock results in differential cracking and eventually forms a bulge; the properties and lithology of the rock matrix significantly affect interface deformation during seepage, exerting a direct impact on the cracking of the repaired layer. These findings have important practical implications for the preventive protection of the Leshan Giant Buddha and other stone cultural heritage sites. By understanding the mechanisms of seepage-induced cracking, conservation efforts can be enhanced, leading to more effective preservation of these significant cultural symbols.

Systematic assessment of the silk deterioration behaviors for silk aging prediction

The silk cultural artifacts have suffered significant deterioration since their discovery, and the unsuitable conditions in the storage environment will further exacerbate this degradation. Systematically and quantitatively assessing the degree of deterioration of silk fabrics with multiple indexes is imperative. In this study, color difference, oxidation degree, crystallinity, and amino acid contents were employed to investigate the aging degradation process of silk fabrics. The results illustrated that both thermal and ultraviolet aging processes were accompanied by discoloration, increasing oxidation degree, decreasing crystalline degree, and amino acid contents reduction. Moreover, the aging level of silk fabrics deterioration behaviors varied across three different stages: (i) the initial stage was primarily marked by color changes, (ii) while oxidation degree and crystallinity alterations dominated in the intermediate phase, (iii) and a substantial reduction in amino acid contents prevailed during the final stage of aging. Therefore, the color difference could be identified as the early safety warning indicator for cultural relics preservation. The GM (1, 1) and GNNM (1, 1) forecasting models were utilized and the results suggested that GNNM (1, 1) outperformed GM (1, 1) in predicting the color properties of silk fabrics, indicating its potential for widespread use in predicting the deterioration of silk artifacts within collections. Collectively, this work comprehensively investigated the degradation process of silk fabrics and further achieved the prediction of color property changes during the simulated aging process, thereby providing a theoretical foundation for the conservation and protection of silk fabrics.

Synthesis of a europium complex with ultrahigh quantum yield and its application as an invisible luminescent additive in pigments for preservation of cultural relics

A europium coordination compound [Eu2(ppip)2(PhCOO)6] (ppip is 1,2-diphenylimidazo[4,5-f][1,10]phenanthroline) has been synthesized and structurally characterized. In this symmetric dinuclear complex of octa-coordinated Eu(III) atom, both hanging phenyl rings in the ppip are twisted dramatically from the imidazophenanthroline part, leading to strong edge-to-face (T-type) C–H∙∙∙π interaction. This pale yellow stable complex possesses an ultrahigh luminescence quantum yield (84.2 ± 0.2%) under excitation at 365 nm, and hence is explored to be utilized in the preservation pigments for traditional Chinese paintings as an luminescent additive, which looks invisible under normal light, but exhibits bright red luminescence under UV excitation at a rather low percentage (0.02% wt).

Energy balanced routing protocol based on improved particle swarm optimisation and ant colony algorithm for museum environmental monitoring of cultural relics

AbstractThe environmental monitoring of cultural relics based on wireless sensor networks in museums demands for the transmission and processing of massive data, which in turn leads to problems, such as heavy network traffic, high time delay, and unbalanced node energy consumption. To solve these problems, an energy balanced routing protocol which can minimise the network energy consumption is proposed. The improved swarm intelligence optimisation algorithm which combined particle swarm optimisation with ant colony optimisation is adopted to construct an environmental monitoring system for cultural relics preservation. Simulation results show that the decrease of the path length for data transmission under the proposed algorithm is 2.5% higher than that of other classical algorithms, indicating that the proposed algorithm can effectively reduce the length of network path and improve the transmission performance of network system. In view of optimisation rounds and simulation time, the energy consumption of the network system under our algorithm is 57.5% less compared with other classical algorithms, and the average residual energy variance is 57.1% less. The cultural relics environmental monitoring system based on the proposed routing protocol has better network load balancing performance.

Surface structured light sensor with simultaneous color mapping

To obtain geometric information and color texture simultaneously, a surface structured light sensor consisting of a monochrome camera, a color camera, and a projector is proposed. The sensor uses a color camera to acquire surface color information while using it as a geometric measurement unit and matching with the monochrome camera to obtain geometric information. Due to the Bayer array and demosaicing algorithm of the color camera, pixel RGB components are always coupled with interference from other channels. However, existing color de-crosstalk in reconstruction is merely applied to the decoupling of color composite patterns, ignoring the intensity errors present in color fringe patterns under monochrome illumination. In our sensor, de-crosstalk of monochromatic patterns is considered to guarantee the reconstruction accuracy. The high-accuracy measurement of the sensor is validated by reconstructing standard steps, yielding a mean absolute error of 0.008 mm for distance measurements. In addition, the reconstruction experiment of a terracotta warrior verifies that the proposed sensor has potential application in the digital preservation of cultural relics.

Design of Control System for Cultural Relics Testing Room Based on STM32

This paper designs a control system for a cultural relic test chamber based on STM32. The system uses the STM32 processor as the underlying main control of oxygen concentration and humidity and uses an industrial all-in-one machine as the bridge to exchange the information between the cloud server and the bottom master controller. The oxygen concentration, humidity and temperature data of the test chamber can be stored on the server in real-time, and the alarm messages are sent through the cloud SMS platform. The results reveal that the oxygen concentration in the test chamber could be adjusted continuously between 0.6% ~ 10% VOL and the relative humidity could be adjusted continuously within 45% ~ 55% RH, and it can keep stable near the set value. The system can meet the requirements of oxygen concentration and humidity for most cultural relics preservation and can also provide a settable constant oxygen concentration and humidity environment for the related research of anoxic treatment and modified atmosphere technology.

Porous Electrospun Films with Reversible Photoresponsive Microenvironmental Humidity Regulation: A Controllable Hydrogen-Bonding Synergistic Effect Exhibited by Acrylic Acid Segments

Suitable relative humidity is essential for the preservation of cultural relics, food storage, and so on. A special material that can regulate the relative humidity in the microenvironment is particularly important. In this work, several innovative electrospun films with reversible photoresponsive wettability and the ability to regulate microenvironmental relative humidity were prepared. The spiropyran unit of the synthesized copolymer played the most important role in humidity regulation due to its reversible transition between a nonpolar ring-closed state and a polar ring-opened state induced by alternating ultraviolet/visible illumination. More interestingly, the introduction of acrylic acid segments exhibited a controllable hydrogen bond synergistic effect for increasing the range of humidity regulation. The color change and the reversible change ranges of wettability and microenvironmental relative humidity under ultraviolet/visible irradiation are all closely related to the number of acrylic acid segments. Cassie theory, density functional theory (DFT), and interaction region indicator (IRI) analysis were used to characterize this phenomenon. Electrospinning is a promising method to achieve large-scale production that can put such material into practical applications.

Biocorrosion of copper metal by Aspergillus niger

Several geoactive fungi were investigated for their biocorrosion impact on metallic copper, to further understanding of the potential roles that fungi may have in the biotransformation of such substrate, and the mechanisms involved. Copper metal showed little toxicity and test fungi were able to grow in direct or indirect contact with copper and to colonize copper sheet. A. niger was able to biodeteriorate copper metal through proton- and ligand-mediated dissolution mechanisms, leading to significant mass loss and surface etching. The formation of a secondary copper oxalate (moolooite) biomineral crust together with cuprite deposition lead to alteration of surface topography and visual appearance, highlighting the significance of oxalate excretion in effecting fungal metal biotransformations. The metal transforming influence of fungal colonization may have some implications for biodeterioration, protection and preservation of cultural relics and artefacts as well as certain components of the built environment.

Experimental investigation on the correlation between rainfall infiltration and the deterioration of wall paintings at Mogao Grottoes, China

The Mogao Grottoes is famous around the world for its exquisite wall paintings and colorful painted sculptures, and was inscribed in the UNESCO World Heritage List in 1987. Although the site is located in an arid area, water is still one of the main factors threatening the long-term preservation of cultural relics. The relationship between rainfall infiltration and wall painting deterioration was investigated as part of efforts to develop conservation strategies to prevent deterioration caused by atmospheric precipitation. This was done through artificial rainfall simulation experiments and high-density electrical non-destructive test. Areas prone to wall painting deterioration, as evidenced by periodic condition assessment, showed an association between further deterioration and natural heavy rainfall. The results show that the covering layer above the grottoes has a small runoff coefficient, and the rainfall infiltration is much larger than the volume of runoff produced. The rainwater migrates preferentially along the rock fractures in the form of gas or through the gaps between the grotto eaves and the rock, or through cracks in the form of liquid. This is the main mechanism for activation of salt damage and deterioration of the wall paintings. The covering layer above the grottoes is thin, and the through-cracks in the surrounding rock or external wooden eaves are particularly vulnerable to rainfall infiltration. This indicates that more attention should be paid to the system of preventive protection by rainwater disposal. This research has important practical value in improving preventive protection of the Mogao Grottoes.

Determination of the ratio of liquid water mass to gaseous water mass in water vapor field

Moisture content of the fractured rock mass in the unsaturated zone cannot be measured or calculated up till now, but liquid water in it is very important for ecological regreening and preservation of cultural relics (frescoes). Determination of the ratio of liquid water mass to gaseous water mass (α) is the key to solve this problem. In the open system, which consists of rock mass, gaseous water and liquid water, two-phase water moves and transforms each other continuously, it is in a non-equilibrium state. When the humidity of the system reaches 100%, it is in a local equilibrium state. According to thermodynamic balance principle, density and mass of liquid water and gaseous water are the same in this system, so the ratio of mass of liquid water to gaseous water α is constant. In this paper, the main aim is to find a way to get the value of α. Experiment is designed to record large numbers of data, and to get an empirical formula to get the value of α. The results show that the relationship between α and temperature can be expressed as an exponential function, and the mass of liquid water is much greater than the mass of gaseous water when gaseous water is saturated. The results are very useful to quantify moisture content of rock mass, and helpful in discussion of the transformation law of gaseous water into liquid water each other.

Study on Monitoring and Controlling of the Environment for Preservation of Cultural Relics in Changzhou Museum

Study on Monitoring and Controlling of the Environment for Preservation of Cultural Relics in Changzhou Museum

Study on Mechanism of Water Condensation and Field Experiments of Thousand-Hand Guanyin in Dazu Rock Carvings

Dazu Rock Carvings is an important heritage. In the past, many varieties of damages existed in Dazu Rock Carvings, which impaired aesthetics and safety. Thus, the country is trying to save the rock carvings through preservation of cultural relics. Among those engaged in this endeavor are leaders and experts from Dazu Rock Carving Institute, Chinese Academy of Cultural Heritage, China University of Geosciences, School of Environment of Tsinghua University. In the research hereof, field experiments and field surveys were carried out, and corresponding measures were put forward for analysis of data.

Electrochemical removal of stains from paper cultural relics based on the electrode system of conductive composite hydrogel and PbO2.

Constructing methods for cleaning stains on paper artworks that meet the requirements of preservation of cultural relics are still challenging. In response to this problem, a novel electrochemical cleaning method and the preparation of corresponding electrodes were proposed. For this purpose, the conductive graphene (rGO)/polyacryamide (PAM)/montmorillonite (MMT) composite hydrogel as cathode and PbO2-based material as anode were prepared and characterized. The electrochemical cleaning efficiencies of real sample and mimicking paper artifacts were evaluated, and the effects of the electrochemical cleaning on paper itself were detected. Based on the above experiments, the following results were obtained. The composite hydrogel with attractive mechanical properties is mainly based on the hydrogen bond interactions between PAM chains and MMT. The results of cleaning efficiency revealed that the black mildew stains together with the yellowish foxing stains were almost completely eliminated within 6 min at 8 mA/cm2, and various stains formed by tideline, foxing, organic dyes and drinks could be thoroughly removed at 4 mA/cm2 within 5 min. In addition, the proposed cleaning method has advantages in local selectivity, easy control of cleaning course, and reusability, which represents a potential utility of this approach.

Local state adaptation and grassroots participation: Tianjin and Nanjing’s preservation of cultural relics in comparative aspects

ABSTRACTBackground: Governance of cultural relics preservation and cultural industry in China have become focal points of academic interests in recent years.Purpose: This article adopts the case of Tianjin and Nanjing to study how the local states balance market incentives and values of preservation, and adapt to new institutional frameworks and social environment in China.Main Arguments: The authors argue that cultural preservation is a process of adaption and learning for both local state and society. This article tries to figure out the new mechanism and actors involved in the process of continuity and change in local China. The local states have learned to cope more subtly with social demands and are now more responsive to the outbreak of new events and social demands through various channels. The cultural elite also search for ways to strike a win–win solution to bridge the interests of various stakeholders. But the law enforcement and policy implementations are still full of confusion and calculation.Conclusion: The authors argue that in order to consolidate the local capacity building, formation of a grass-roots identity will lay the long-term foundation for autonomous mechanism of collaborative governance in cultural relics preservation in China.

SCRMS: An RFID and Sensor Web-Enabled Smart Cultural Relics Management System.

Cultural relics represent national or even global resources of inestimable value. How to efficiently manage and preserve these cultural relics is a vitally important issue. To achieve this goal, this study proposed, designed, and implemented an RFID and Sensor Web–enabled smart cultural relics management system (SCRMS). In this system, active photovoltaic subtle energy-powered Radio Frequency Identification (RFID) is used for long-range contactless identification and lifecycle management of cultural relics during their storage and circulation. In addition, different types of ambient sensors are integrated with the RFID tags and deployed around cultural relics to monitor their environmental parameters, helping to ensure that they remain in good condition. An Android-based smart mobile application, as middleware, is used in collaboration with RFID readers to collect information and provide convenient management for the circulation of cultural relics. Moreover, multiple sensing techniques are taken advantage of simultaneously for preservation of cultural relics. The proposed system was successfully applied to a museum in the Yongding District, Fujian Province, China, demonstrating its feasibility and advantages for smart and efficient management and preservation of cultural relics.

Glass composite as robust UV absorber for biological protection

UV-blocking materials are increasingly important in a variety of applications such as biological shield, cultural relics preservation and radiation hardening of electronic devices. A paramount challenge is the search for approaches that can produce material candidates combing both high ultraviolet absorbing capacity and low activity. Here we introduce an effective self-limited nanocrystallization method for construction of transparent Ce-containing glass composite. The unique crystallization process allows the in situ precipitation of UV absorbing center spanning a wide range of activation temperature, benefiting from the capability of viscous glassy matrix for modulating O2- and F- migrations. Photocatalysis/catalysis and UV-shielding tests firmly demonstrated that the obtained glass composite possesses suppressed photocatalytic/catalytic activity and excellent UV-blocking performance for both organics and bioactive cells. Our results suggest an innovative approach for fabrication of robust UV absorber that should find practical applications in protection of living creatures or cultural relics, especially in the case of direct contact with organic molecules or living cells.

Long-term stability of large span caverns at the 1400-year Heidong quarry

Long-term stability of large span caverns is earnest but poorly understood in preservation of cultural relics. The life span of huge caverns is difficult to extrapolate from short period of monitoring or laboratory testing. A huge ancient quarry with 21 caverns whose original status is well kept over 1400 years was found in Tiantai County of South China. One of the caverns has an 81 m span which is far beyond the 50 m expectation on current knowledge. The tension at the core of long stability is the excavation speed versus deliberation. Here we show a unique technique of Digging Holes for Quarrying Vertical Flagstone (DQF) invented by ancestors to ensure the safety, which is much smarter compared to blasting and casting technique that commonly used after the Industrial Revolution. Furthermore, in addition to selecting competent massive rocks via cutting normally to and through faults, they adopted systematically trial adits, dome-shaped cavern, and disposal of waste rocks inside caverns for support. These ancient achievements mark a high level of quarrying in complex natural conditions with manpower. The results are positive to extend our knowledge in category design of cavern scale and stability assessment, and to some extent, they give solutions to the conflict between fast excavation with blasting and induced excavation damaged zone (EDZ) in surrounding rocks.

Application of Multi-Baseline Digital Close-Range Photogrametry Technique in 3D Reconstruction of Underground Tomb

The theory and characteristics of the multi-baseline digital close-range photogrametry were discussed to be used in cultural relics preservation. Take the 3D reconstruction project of the Yu Shan the 5th mural tomb in Ji-an as an example, two methods were put forward to measure the control points of the image without any harm to the object. Also, Tricolor cool tone electron energy conservation lamp was used to meet the strict color control of the mural images. Engineering tests show that the methods put forward could greatly reduce the field work and labor intensity with the characteristics of high accuracy, automation and efficiency. Production efficiency is improved as well. The precision of mapping and image texture satisfies the requirements of cultural relics preservation. In addition, how to manage and index such data through database technology needs further study.