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The purpose of constructing a degradation index (DI) is to better characterize the degradation degree of mechanical transmission compared with relying solely on spectral oil data, which leads to an accurate estimation of the failure time when the transmission no longer fulfills its function.

The DI is modeled using a weighted average function with two desirable properties: maximizing the monotonic trend and minimizing the variance of failure threshold between different transmissions. The method includes concentration modification, data selection and data fusion steps that lead to a reasonable mechanical transmission degradation model. The proposed methodology was verified through a case study involving multispectral oil data sampled from several power-shift steering transmissions.

The results show that the DI outperforms all spectral oil data. Compared with the existing spectral oil data-based degradation modeling approach for mechanical transmissions, the present methodology provides an accurate RUL prediction.

There are several important directions for future research: First, more degradation data (i.e. ferrography) that are tailored to the degradation modeling of mechanical transmission need to be involved. Second, more effective degradation data selection methodologies that are applicable for multiple data types need to be developed. Third, kernel methods that can fuse the nonlinear degradation data need to be investigated.

The novelty of this methodology lies in integrating the multiple degradation data in a unified DI. And the main contribution of this paper is to establish a new direction in degradation modeling and RUL prediction of mechanical transmission.

This paper aims to find a suitable solution to degrade the C.I. Reactive Red 24 (RR24) dyeing wastewater by using sodium persulphate to recycle water and inorganic salts.

The effects of temperature, the concentration of inorganic salts and Na₂CO₃ and the initial pH value on the degradation of RR24 were studied. Furthermore, the relationship between free radicals and RR24 degradation effect was investigated. Microscopic routes and mechanisms of dye degradation were further confirmed by testing the degradation karyoplasmic ratio of the product. The feasibility of the one-bath cyclic dyeing in the recycled dyeing wastewater was confirmed through the properties of dye utilization and color parameters.

The appropriate conditions were 0.3 g/L of sodium persulphate and treatment at 95°C for 30 min, which resulted in a decolorization rate of 98.4% for the dyeing wastewater. Acidic conditions are conducive to rapid degradation of dyes, while ·OH or SO₄⁻· have a destructive effect on dyes under alkaline conditions. In the early stage of degradation, ·OH played a major role in the degradation of dyes. For sustainable cyclic dyeing of RR24, inorganic salts were reused in this dyeing process and dye uptake increased with the times of cycles. After the fixation, some Na₂CO₃ may be converted to other salts, thereby increasing the dye uptake in subsequent cyclic staining. However, it has little impact on the dye exhaustion rate and color parameters of dyed fabrics.

The recommended technology not only reduces the quantity of dyeing wastewater but also enables the recycling of inorganic salts and water, which meets the requirements of sustainable development and clean production.

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 examine the impact of income inequality and shadow economy on environmental degradation given the growing income inequality, shadow economy and ecological degradation in developing countries. Thus, this study is motivated to offer empirical insight into how income inequality and shadow economy influence the environment in African countries.

Data from 29 countries in Africa between 2000 and 2017 were used, while the novel method of moments quantile regression of Machado and Silva (2019) and Dumitrescu and Hurlin (D-H) (2012) granger causality is used as the estimation techniques.

The results established the presence of cross-sectional dependence and slope heterogeneity in the panel, while Westerlund panel cointegration confirmed the long-run cointegration among the variables. The results from the quantile regression suggest that income inequality increases environmental degradation from the 5th to the 30th quantiles, while from the 70th quantiles, income inequality reduces ecological degradation. The shadow economy negatively influences environmental degradation across the quantiles, strengthening environmental quality. Per capita income (economic growth) and financial development positively impact environmental degradation throughout the quantiles. However, urbanization reduces environmental degradation from 60th to 95th quantiles. The D-H causality established a two-way relationship between income inequality and environmental degradation, while one-way from shadow economy, per capita income and urbanization to environmental degradation were established.

This study provides fresh insights into the nexus between shadow economy and environmental quality in the presence of higher levels of income inequality for the case of African region. The study applies quantile analysis via moment proposed by Machado and Silva (2019). This technique shows that the impact of income inequality and shadow economy on environmental degradation is heterogeneous across the quantiles of ecological footprints in Africa.

While there are enormous studies on the determinants of environmental degradation, empirical studies on the effect of renewable energy consumption and economic growth on the environment remain limited. The purpose of this paper is to examine the asymmetric effect of renewable energy consumption and economic growth on environmental degradation in 31 selected sub-Saharan African countries spanning from 1990 to 2018.

To examine possible asymmetric effects of the exogenous variables on environmental degradation, we used the panel nonlinear autoregressive distributed lag approach and secondary data was sourced from the World Bank (2021).

The cointegration test results suggest that there is a long-run cointegration among the variables whereas our main findings indicate that environmental degradation responds asymmetrically to changes in renewable energy consumption and economic growth. The results further reveal that both positive and negative shocks in renewable energy consumption reduce environmental degradation. On the other hand, positive and negative shocks in economic growth increase environmental degradation in the long run.

The implications of this study include the need for policymakers in sub-Saharan Africa to encourage the utilization of renewable energy as it reduces environmental degradation. Also, governments in the subregion should gradually replace the usage of fossil fuels by adapting renewable energy sources so as to achieve higher economic growth.

The positive and negative shocks of renewable energy consumption and economic growth on environmental degradation are examined to ascertain their asymmetric relationships.

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 present study is concerned with the application of a nonlinear frequency analysis approach to the detection and location of water tree degradation of power cable XLPE insulation without turning off electric power.

The use of power cable system responses to power line carrier signals are proposed to conduct the required signal analysis for damage location purpose. This technique is based on the fact that the water tree degradation in power cables can make the system behave nonlinearly. Consequently, the location of water tree degradation can be determined by detecting the position of nonlinear components in power cable systems.

A novel method has been proposed for locating water tree degradation in power cable systems; numerical simulation studies have demonstrated the effectiveness of the new technique.

The proposed technique has the potential to be applied in practice to more effectively resolve the power cable damage location problem.

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.

As the physical dimensions of the devices are reduced to the submicrometer regime, the hot‐carrier reliability has become an important issue in the scaling of the p‐MOSFET as well as the n‐MOSFET. In this paper, we present a unified approach for p‐MOSFET degradation due to the trapping of the hot electrons in the gate oxide layers. A physical analytical model, based on the pseudo two‐dimensional model, is derived for the first time to describe the linear and saturation drain current degradation. The model has been verified by comparing the calculation and the measurement from submicron p‐MOSFET's with different channel lengths and oxide thickness. There are no empirical parameters in the model. Two physical parameters: the capture cross section and the density of states of electron traps, which can be determined independently from the measured degradation characteristics, are valid for both the linear current and the saturation current degradation. The simple expression is very suitable for the predicting of the circuit reliability.

The purpose of this paper is to analyze the dependent competing failure reliability of harmonic drive (HD) with strength failure and degradation failure.

Based on life tests and stiffness degradation experiments, Wiener process is used to establish the accelerated performance degradation model of HD. Model parameter distribution is estimated by Bayesian inference and Markov Chain Monte Carlo (MCMC) and stiffness degradation failure samples are obtained by a three-step sampling method. Combined with strength failure samples of HD, copula function is used to describe the dependence between strength failure and stiffness degradation failure.

Strength failure occurred earlier than degradation failure under high level accelerated condition; degradation failure occurred earlier than strength failure under medium- or low-level accelerated condition. Gumbel copula is the optimum copula function for dependence modeling of strength failure and stiffness degradation failure. Dependent competing failure reliability of HD is larger than independent competing failure reliability.

The reliability evaluation method of dependent competing failure of HD with strength failure and degradation failure is first proposed. Performance degradation experiments during accelerated life test (ALT), step-down ALT and life test under rated condition are conducted for Wiener process based step-down accelerated performance degradation modeling.