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This paper aims to identify the most common fungal species that grow on paper manuscripts and cause bio-deterioration. It also detects the impact of additive materials on fungal degrading and builds a wide database. Thus, it helps conservators understand this phenomenon.

In total, 15 samples were collected from different paper manuscripts suffering from fungi. The achievement of the study objectives depends on using a variety of analyzes, such as a microbiological study, which indicated that three main fungi grew on the paper samples. Then, a digital microscope and an environmental scanning electron microscope were used to detect the effect of fungi on paper fibers. Fourier transform infrared microscopy was used to identify the binding medium and the X-ray diffraction method was used to measure the crystallinity index of cellulose of the paper samples.

Arabic gum was used as a binder medium with the samples. Aspergillus Niger, Aspergillus Fumigatus and Aspergillus Clavatus were the most common fungal species that grew on the Qur’an papers under investigation. They also caused much common damage to the paper samples. The results of the analyzes also showed that the highest crystallinity index of cellulose was in the samples that contained the lowest rate of fungal growth.

This paper highlights the relationship between fungal degradation and the multi-component nature of paper manuscripts. It builds a wide database that correlates the composition and the degradation of the Qur’an papers.

This paper aims to investigate the effect of acidity on the morphology of archeological paper, especially in the presence of colors and whether natural pigments play a role in the process of degradation.

The morphological changes in the cellulosic fibers of the manuscripts because of acidity were investigated using environmental scanning electron microscope (ESEM). Ten historical samples were collected from different manuscripts suffering from acidity. X-ray diffraction was used to identify the inks and pigments that were used in some samples. Additionally, Fourier transform infrared microscopy was used to identify the binding medium.

The results confirmed that carbon ink, ultramarine, cinnabar and gold pigments were applied to some manuscripts with Arabic gum. As for ESEM investigation, the results proved that acidity badly affected the integrity of the cellulosic fibers resulting in their embrittlement. The micrographs showed differences in fiber degradation according to pH value. The presence of inks and pigments increased the degradation extent resulting from acidity.

This paper addresses a specific need to study the behavior of degradation in paper manuscripts, thus helping the conservators find solutions to the phenomenon.

The purpose of this paper is to analyze the time-dependent reliability of harmonic drive.

The transient finite element analysis (FEA) of harmonic drive is established to calculate the stress under different loads. Combined with the residual strength model and random variables, the time-dependent reliability model of harmonic drive is deduced by the stochastic perturbation method and Edgeworth series. Based on accelerated life tests, the degradation parameters are estimated by maximizing likelihood function. Under variable load, the key stress from transient FEA is transformed into probability density function by kernel density estimation, and the residual strength model is modified by adding adjustment factors to deal with strength degradation under different loads.

The critical position of stress concentration from transient FEA is consistent with the fatigue fracture position at the accelerated life test sample. Compared with the time-dependent reliability method with equivalent circular-shell static stress or empirical degradation parameters, the proposed method has the smallest prediction error of failure life. Under variable load, the state function should be expanded to second-order series for avoiding error items relevant to variance. The failure life expectation under random variable load is smaller than that under constant load.

The time-dependent reliability method of harmonic drive is firstly proposed under constant and variable load. The transient FEA of harmonic drive is established to calculate the stress for strength analysis. The accelerated life test of harmonic drive is conducted for degradation parameters estimation. The adjustment factor is added to the residual strength model for strength degradation under different loads.

The purpose of this paper is to propose an improved multi-objective optimization model for the condition-based maintenance (CBM) of single-component systems which considers periodic imperfect maintenance and ecological factors.

Based on the application of non-periodic preventive CBM, two recursion models are built for the system: hazard rate and the environmental degradation factor. This paper also established an optimal multi-objective model with a normalization process. The multiple-attribute value theory is used to obtain the optimal preventive maintenance (PM) interval. The simulation and sensitivity analyses are applied to obtain further rules.

An increase in the number of the occurrences could shorten the duration of a maintenance cycle. The maintenance techniques and maintenance efficiency could be improved by increasing system availability, reducing cost rate and improving degraded condition.

In reality, a variety of environmental situations may occur subsequent to the operations of an advanced manufacturing system. This model could be applied in real cases to help the manufacturers better discover the optimal maintenance cycle with minimized cost and degraded condition of the environment, helping the corporations better fulfill their CSR as well.

Previous research on single-component condition-based predictive maintenance usually focused on the maintenance costs and availability of a system, while ignoring the possible pollution from system operations. This paper proposed a modified multi-objective optimization model considering environment influence which could more comprehensively analyze the factors affecting PM interval.

This study aims to restore the lost mechanical properties of the prints with carrageenan, methyl hydroxyethyl cellulose (Tylose) and hydroxypropyl methylcellulose (Methocel).

The effect of these materials on the properties of the printed paper (modern and historical samples) has been evaluated under the influence of accelerated aging using pH measurement, the mechanical properties (tensile and elongation), FTIR and color changes.

The three consolidates reduced the acidity of treated samples significantly, but after ageing, it was observed that the pH of aged treated samples decreased slightly as compared to the untreated samples. The results of the mechanical properties showed the superiority of hydroxypropyl methylcellulose (Methocel) in improving the tensile and elongation forces of the samples compared to carrageenan and methyl hydroxyethyl cellulose even during the accelerated aging. Consolidation materials succeeded in reducing ΔE of the paper samples under accelerated aging, especially carrageenan. The IR spectra confirmed that no dramatic difference was observed in topically function vibrations of samples after treatment beside that the O-H stretching band intensity increased observably after treatment with the three consolidates, after ageing the treatment, and it protected the treated paper from oxidation processes as the infrared spectrum analysis showed a decrease in intensities of carbonyl and carboxyl groups as compared to aged untreated samples.

The research provides new biopolymers in strengthening the historical printed paper, where printed papers lack studies related to their conservation. This makes the current study a promising step for treating historical printed paper.

The purpose of this paper is to study various reliability measures like reliability, mean time to failure (MTTF) and sensitivity of transformer including different parameters of insulating oil/paper as health index.

The reliability characteristics of transformer incorporating different parameters of insulating oil as well as paper have been evaluated using Markov process incorporating Gumbel–Hougaard copula, Laplace transforms and supplementary variable technique. The parameters taken into consideration are breakdown voltage (BDV) and moisture content (MC) of both insulating oil and paper, and other parameters considered are interfacial tension (IFT), dissipation factor (DF), degree of polymerization (DOP) and furanic content (FC) for insulating oil and paper, respectively. By probability consideration and continuity influence, difference-differential equations have been obtained for the considered model.

Transition state probabilities, reliability, MTTF and sensitivity of the transformer corresponding to different parameters of insulating oil and paper have been evaluated with the help of aforementioned technique. Variations of reliability with respect to time along with the variations of MTTF and sensitivity have also been examined. Remarkable points during the study have also been pointed out.

Reliability characteristics of the transformer have been evaluated including two parameters: insulating oil and paper with the help of supplementary variable technique, considering two different types of repairs incorporating Gumbel–Hougaard family of copula unlike done earlier. Reliability, MTTF and sensitivity of transformer have been analyzed considering the parameters: BDV, MC, IFT and FC of insulating oil, and BDV, MC, DOP, DF of insulating paper.

This paper aims to present the components' characterization and condition assessment of an important deteriorated Mamluk-illuminated paper manuscript housed in Al-Azhar Library, Egypt.

Different analytical techniques used in this study were the portable digital optical microscope, stereomicroscope, scanning electron microscope with EDX (SEM.EDX), portable X-ray fluorescence (pXRF), X-ray diffraction (XRD), pH measurement and Fourier transform infrared spectroscopy (FTIR).

The results obtained by different microscopes showed that the gilding in the surface of illuminated paper sheets was performed with gold leaves. Additionally, these microscopes revealed that the illuminated paper manuscript has different aspects of deterioration such as adhered dirt, staining, some micro-cracks, cracks and detachment of some parts in some illuminated areas. The results of elemental analysis by EDX, portable XRF and XRD analysis showed that the orange red pigment is red lead (Pb₃O₄), blue pigment is azurite (2CuCo₃.Cu (OH)₂), and the gold layer is has consisted of brass alloy (Cu-Zn) with a small amount of gold element (Au). The pH measurement stated that the historical paper in the acidity level. The ATR-FTIR analysis also revealed the oxidation of cellulose. Moreover, it was found from ATR-FTIR that Arabic gum was used as a binder for the pigments.

This study presents the important results of analytical methods used for condition assessment and identification of the components of an important Mamluk-illuminated paper manuscript, where these results referred that the studied paper manuscript had different aspects of deterioration. The conservation steps either conservation treatment or preventive conservation are urgently needed in future studies.

This paper aims to analyze the legal framework of land degradation in Asia and provide market shared liability as a new theory to solve a problem regarding the difficulty for judges to determine the percentage of compensation for corporations responsible for land degradation. This paper aims also presents a theory to solve the problem of the vacuum of legal responsibility theory, which can make corporations proportionally responsible in terms of causing land degradation.

This was done through legal research methods, mainly with systematical interpretation. The approach used in this paper is conceptual, statute and comparative approach.

By analyzing the related legal norms, it can be understood that in Asian countries, such as Indonesia, Thailand and Malaysia, there are regulations regarding land degradation. However, the regulations in these countries are not specific and tend to focus on nature conservation, which has an impact on handling land degradation. Therefore, it needs special regulation to deal with land degradation. One of the things that need to be regulated about land degradation is a market shared liability.

This research is limited to regulation in the Asia region. By analyzing the regulation, this paper will provide an analysis about the land degradation regulation mechanism in Asia and give an analysis about market shared liability as one of the solution to handling land degradation. Having the same ground rules will create synergies between countries in Asia to handle land degradation.

This paper is the first systematic legal research comparing regulations from three nations in Asia on land degradation and the first paper to provide market shared liability as a solution to handling land degradation.

The purpose of this paper is to describe a novel methodology for predicting reliability for consumer electronics or any other hardware systems that experience a complex lifecycle environmental profile.

This Physics-of-Failure–based three-step methodology can be used to predict the degradation rate of a population using a Monte Carlo approach. The three steps include: using an empirical equation describing the degradation of a performance metric, a degradation consistency condition and a technique to account for cumulative degradation across multiple life-cycle stress conditions (e.g. temperature, voltage, mechanical load, etc.).

Two case studies are provided to illustrate the methodology including one related to repeated touch-load induced artifacts for displays.

This novel methodology can be applied to a wide range of applications from mechanical systems to electrical circuits. The results can be fed into the several stages of engineering validation to speed up product qualification.

The purpose of this paper is to provide estimates of damage cost for several areas of the environment. In particular: to estimate the cost of degradation as a percentage of gross domestic product (GDP) at the national level; to enhance local capacity in environmental economics, in particular in the valuation of environmental degradation; and to provide an input to inter‐sectoral environmental priority setting.

To achieve the above objectives a framework was developed to estimate the cost of environmental degradation in seven countries in the region, for six categories. Estimates reflect order of magnitude and therefore represent an indication of actual damage costs. A range of estimates was provided to reflect the uncertainty of the results. Damage costs are presented in annual values (in local currencies, in US$ dollars) and as a per cent of GDP. Expressing costs as a share of GDP provides a sense of magnitude and will allow cross‐country comparison.

The damage cost of environmental degradation in Middle East and North Africa (MENA) in 2000 is estimated at US$ 9 billion per year, or 2.1‐7.4 per cent of GDP, with a mean estimate of 5.7 per cent of GDP. In addition, the damage cost to the global environment is estimated at 0.5‐1.6 of GDP, with a mean estimate of 0.9 per cent of GDP.

Owing to data constraints, no cost estimates are provided for some impact such as: degradation associated with industrial, hazardous and hospital waste, biodiversity loss, and impact of inadequately treated wastewater, thus calculations often represent lower bound estimates.

This paper is a contribution in a process towards the use of environmental damage cost assessments for priority setting and as an instrument for integrating environmental consideration into economic and social development.