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The purpose of this study is to make a prediction of China's energy consumption structure from the perspective of compositional data and construct a novel grey model for forecasting compositional data.

Due to the existing grey prediction model based on compositional data cannot effectively excavate the evolution law of correlation dimension sequence of compositional data. Thus, the adaptive discrete grey prediction model with innovation term based on compositional data is proposed to forecast the integral structure of China's energy consumption. The prediction results from the new model are then compared with three existing approaches and the comparison results indicate that the proposed model generally outperforms existing methods. A further prediction of China's energy consumption structure is conducted into a future horizon from 2021 to 2035 by using the model.

China's energy structure will change significantly in the medium and long term and China's energy consumption structure can reach the long-term goal. Besides, the proposed model can better mine and predict the development trend of single time series after the transformation of compositional data.

The paper considers the dynamic change of grey action quantity, the characteristics of compositional data and the impact of new information about the system itself on the current system development trend and proposes a novel adaptive discrete grey prediction model with innovation term based on compositional data, which fills the gap in previous studies.

The literature on marriage formation neglects different pathways to marriage. This study focuses on arranged marriage, introduced marriage, and self-initiated marriage as three main marriage pathways in East Asia and examines how people’s marriage pathway choices are associated with education and change over time in mainland China, Japan, South Korea, and Taiwan. Using data from the East Asian Social Survey, this study finds that education is associated with fewer arranged marriages and more self-initiated marriages and that more recent marriage cohorts also witness a decline in arranged marriages and an increase in self-initiated marriages. However, how introduced marriage is associated with education and change over time varies in four East Asian societies. The findings support the “developmentalism-marriage” framework that developmental idealism leads to modern marital practices.

The purpose of the study reported in this paper was to investigate the process for the preparation of carboxymethyl chitosan (CMCS) hydrogel and to characterize such a hydrogel via various analytical techniques.

The hydrogel in the aqueous solution was prepared by using CMCS as the raw material and glutaraldehyde as the crosslinking agent. The as-prepared CMCS hydrogel was characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared (FTIR) spectra, differential scanning calorimetry, X-ray diffraction (XRD) and ultraviolet-visible (UV-vis) spectra.

The CMCS hydrogel possessed a porous structure and the shape of the pore was irregular. Generally, the diameter of the pores ranged from 20 to 70 nm. The results from FTIR, UV-vis and XRD showed that there was no obvious difference between the structures of the CMCS hydrogel and CMCS powder.

The strength of the hydrogel is not high enough and the degree of swelling is relatively small. So, improving the strength and swelling degree of the hydrogel is necessary.

The CMCS hydrogel presented obvious hollow structures and its fabrication was processed absolutely in aqueous phase. Besides, it possessed low toxicity, good biocompatibility and biodegradability. So, the hydrogel will have potential applications in drug delivery and release, tissue engineering and other biomedical fields.

This paper is the first to present the relationship between the structures of the CMCS hydrogel and CMCS micromolecule, and it confirms that there is no fundamental difference between them.

The purpose of this paper is to summarize progress of grey forecasting modelling, explain mechanism of grey forecasting modelling and classify exist grey forecasting models.

General modelling process and mechanism of grey forecasting modelling is summarized and classification of grey forecasting models is done according to their differential equation structure. Grey forecasting models with linear structure are divided into continuous single variable grey forecasting models, discrete single variable grey forecasting models, continuous multiple variable grey forecasting models and discrete multiple variable grey forecasting models. The mechanism and traceability of these models are discussed. In addition, grey forecasting models with nonlinear structure, grey forecasting models with grey number sequences and grey forecasting models with multi-input and multi-output variables are further discussed.

It is clearly to explain differences between grey forecasting models with other forecasting models. Accumulation generation operation is the main difference between grey forecasting models and other models, and it is helpful to mining system developing law with limited data. A great majority of grey forecasting models are linear structure while grey forecasting models with nonlinear structure should be further studied.

Mechanism and classification of grey forecasting models are very helpful to combine with suitable real applications.

The main contributions of this paper are to classify models according to models' structure are linear or nonlinear, to analyse relationships and differences of models in same class and to deconstruct mechanism of grey forecasting models.

The purpose of this paper is to investigate the mechanical behavior and propagation of cracks of numerical granite samples through the Brazilian split test and to provide a reference for predicting the behavior of real granite samples.

The numerical models of granite containing two fissures are established using the parallel bond model (PBM) and the smooth joint model (SJM) in PFC2D. The peak stresses, number of cracks and anisotropic ratios are obtained to study the influence of the mineral composition and the angle of inclination of rock bridge on the strength, failure mode and deformation characteristics.

The numerical results obtained show that the mineral composition has a marginal influence on the peak stress. When the angle of inclination of rock bridge β increases, the peak stress drops to its minimum value at β = 90° and then gradually increases to a relatively low level. The behavior of cracks falls into three categories based on the distribution of cracks. By analyzing the stress–strain curve and the process of crack propagation for sample No. 4 with β = 60°, it is found that the process of failure can be divided into four stages and tensile cracks dominate. The anisotropic ratios of peak stress and a number of cracks obtained show that the peak stress is low anisotropic and the number of cracks is medium anisotropic.

This paper presents a numerical simulation method to analyze mechanical behavior and propagation of cracks under different conditions. The proposed method and the results obtained are useful for predicting the behavior of real granite samples in laboratory and engineering projects.

This paper aims to analyze the influence of rotated anisotropy on the stability of slope, the random finite element method is used in this study.

The random field is generated by the discrete cosine transform (DCT) method, which can generate random field with different rotated angles conveniently.

Two idealized slopes are analyzed; it is observed that the rotated angle significantly affects the slope failure risk. The two examples support the conclusion that when the orientation of the layers is nearly perpendicular to the slip surface, the slope is in a relative stable condition. The results of heterogeneous slope with two clay layers demonstrate that the rotated angle of lower layer mainly controls the failure mechanism of the slope, and the rotated angle of upper layer exhibits a significant influence on the probability of slope failure.

The method for rotated anisotropy random field generation based on the DCT has a simple expression with few parameters and is convenient for implementation and practical application. The proposed method and the results obtained are useful for analyzing the stability of the heterogeneous slopes in engineering projects.

In recent years, numerous studies have investigated whether individual executives and their characteristics relate to financial reporting choices. In this article, we review archival, experimental and survey research on the influence of individual executives on corporate financial reporting and use upper echelons theory as our organizing framework. Our review of 60 studies shows that research consistently finds that top management executives exert significant influence on financial reporting decisions, particularly on disclosure quality. Empirical research has developed promising approaches to investigate executives' psychological attributes and character traits. The results of studies examining the influence of demographic characteristics of individual executives are, however, sometimes contradictory and ambiguous. Nevertheless, the overall empirical results we review are supportive of upper echelons predictions. Additional research in this field is needed to clarify the influence of unexamined upper echelon characteristics, important moderator variables, and adverse selection effects. We also suggest that future research more closely investigates the magnitudes of managerial influence and adopts a more holistic perspective on financial reporting outcomes.

This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat transfer.

A brief review of current research on supercritical aviation kerosene is presented in views of the surrogate model of hydrocarbon fuels, chemical cracking mechanism of hydrocarbon fuels, thermo-physical properties of hydrocarbon fuels, turbulence models, flow characteristics and thermal performances, which indicates that more efforts need to be directed into these topics. Therefore, supercritical thermal transport of n-decane is then computationally investigated in the condition of thermal pyrolysis, while the ASPEN HYSYS gives the properties of n-decane and pyrolysis products. In addition, the one-step chemical cracking mechanism and SST k-ω turbulence model are applied with relatively high precision.

The existing surrogate models of aviation kerosene are limited to a specific scope of application and their thermo-physical properties deviate from the experimental data. The turbulence models used to implement numerical simulation should be studied to further improve the prediction accuracy. The thermal-induced acceleration is driven by the drastic density change, which is caused by the production of small molecules. The wall temperature of the combustion chamber can be effectively reduced by this behavior, i.e. the phenomenon of heat transfer deterioration can be attenuated or suppressed by thermal pyrolysis.

The issues in numerical studies of supercritical aviation kerosene are clearly revealed, and the conjugation mechanism between thermal pyrolysis and convective heat transfer is initially presented.

The purpose of this paper is to investigate the specifics of the relationship between audit committee characteristics and earnings management in Russian listed companies. This research is driven by the possibility of placing this relationship within the context of a specific institutional environment for company performance.

The authors apply a panel study of 184 Russian listed companies for the period 2014–2018. In addition to the standard fixed effects model, the authors test the results for potential endogeneity with two-stage least squares (2SLS) analysis.

The results show that audit committee representation on the board of directors results in some mitigation of earnings management. Results reveal that a higher level of audit committee independence and the presence of financial expertise on the committee are associated with lower earnings management. However, companies with relatively busy directors on audit committees are more inclined to practice earnings management. The study’s findings hold after testing for endogeneity of audit committee independence. The authors also reveal that some audit committee characteristics (for example, audit committee independence; its level of expertise) alleviate earnings management in listed state-owned companies (SOEs) more strongly than in listed non-SOEs.

The results add to the ongoing debate on the role of corporate governance mechanisms in mitigating earnings management in emerging markets by taking into account the type of ownership (state-owned vs private) as a moderating variable. This study reveals, in particular, that the effect of certain audit committee characteristics on earnings management is more prominent in listed SOEs than in listed non-SOEs.