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Many waste-to-energy (WTE) plants are constructed and operated using the public-private partnership (PPP) mode in China. However, risk events of PPP WTE incineration projects sometimes occur. This study aims to clarify the relationship of risks in China's PPP WTE incineration projects and identify the key risks accordingly and risk transmission paths.

A risk list of PPP WTE incineration projects was obtained based on literature analysis. Moreover, a hybrid approach combining fuzzy sets, decision-making trial and evaluation laboratory (DEMATEL) and interpretive structural modeling (ISM) was developed to analyze the causality of risks, explore critical risks and reveal the risk transmission paths. The quantitative analysis process was implemented in MATLAB.

The results show that government decision-making risk, government credit risk, government supervision behavior risk, legal and policy risk, revenue and cost risk and management capacity risk are the critical risks of PPP WTE incineration projects in China. These critical risks are at different levels in the risk hierarchy and often trigger other risks.

Currently, there is a lack of exploration on the interaction between the risks of PPP WTE incineration projects. This study fills this gap by examining the key risks and risk transfer pathways of PPP WTE incineration projects from the perspective of risk interactions. The findings can help the public and private sectors to systematically understand the risks in PPP WTE incineration projects, thus enabling them to identify the risks that need to be focused on when making decisions and to optimize risk prevention strategies. The proposed hybrid approach can offer methodological ideas for risk analysis of other types of PPP projects.

The purpose of this paper is to investigate the hydrodynamic performance of liquid film seals with oblique grooves (OGs) and spiral grooves (SGs), considering cavitation, compare and analyze the differences between them.

Considering cavitation effect, the incompressible steady-state Reynolds equation was solved to obtain the sealing performance parameters of the liquid film seal with oblique groove and spiral groove.

The hydrodynamic performance of oblique groove seal (OGS) and spiral groove seal (SGS) shows a similar trend with the change of operating parameters. When the groove angle is less than 20°, the load-carrying capacity of SGS is better than that of OGS, while when the groove angle continues to increase, the hydrodynamic performance of OGS is slightly better than that of SGS, and more suitable for use under small differential pressure and high speed.

The hydrodynamic characteristics of liquid film seals with oblique grooves and spiral grooves considering cavitation effect were studied, which provides a theoretical reference for the application of oblique groove seal.

The purpose of this paper is to investigate the effects of surface topography, including surface roughness, circumferential waviness and radial taper, on hydrodynamic performance of liquid film seals considering cavitation.

A mathematical model of liquid film seals with surface topography was established based on the mass-conservative algorithm. Liquid film governing equation was discretized by the finite control volume method and solved by the Gauss–Seidel relaxation iterative algorithm, and the hydrodynamic performance parameters of liquid film seals were obtained considering surface roughness, circumferential waviness and radial taper separately.

The results indicate that the values of load-carrying capacity and frication torque are affected by the surface topography in varying degrees, but the effect is limited.

The results presented in the study are expected to aid in determining the optimum value of structural parameters for the optimum seal performance because of the realistic model which considers both surface topography and cavitation.

Walking on inclined ground is an important ability for humanoid robots. In general, conventional strategies for walking on slopes lack technical analysis in, first, the waist posture with respect to actual robot and, second, the landing impact, which weakens the walking stability. The purpose of this paper is to propose a generic method for walking pattern generation considering these issues with the aim of enabling humanoid robot to walk dynamically on a slope.

First, a virtual ground method (VGM) is proposed to give a continuous and intuitive zero-moment point (ZMP) on slopes. Then, the dynamic motion equations are derived based on 2D and 3D models, respectively, by using VGM. Furthermore, the waist posture with respect to the actual robot is analyzed. Finally, a reformative linear inverted pendulum (LIP) named the asymmetric linear inverted pendulum (ALIP) is proposed to achieve stable and dynamical walking in any direction on a slope with lower landing impact.

Simulations and experiments are carried out using the DRC-XT humanoid robot platform with the aim of verifying the validity and feasibility of these new methods. ALIP with consideration of waist posture is practical in extending the ability of walking on slopes for humanoid robots.

A generic method called ALIP for humanoid robots walking on slopes is proposed. ALIP is based on LIP and several changes, including model analysis, motion equations and ZMP functions, are discussed.

The purpose of this paper is to explore whether firms with powerful chief executive officers (CEOs) tend to invest (more) in corporate social responsibility (CSR) activities as the over-investment hypothesis based on classical agency theory predicts.

This paper tests an alternative hypothesis that if CSR investment is indeed an agency cost like the over-investment hypothesis suggests, then those activities may destroy firm value.

Using CEO pay slice (Bebchuk et al., 2011), CEO tenure, and CEO duality to measure CEO power, the authors show that CEO power is negatively correlated with firm’s choice to engage in CSR and with the level of CSR activities in the firm. Furthermore, the results suggest that CSR activities are in fact value enhancing in that as firms engage in more CSR activities their value increases.

The first paper to study CEO power and CSR and their impact on firm value.

People generally believe that business with negative word-of-mouth, such as negative customer reviews can hardly have good sales. But a number of intriguing examples seem to contradict such beliefs. Academic has so far begun to explore the possible positive effect of negative customer reviews, but without unfolding its underlying mechanism. This paper proposes a mechanism through which the variance of customer reviews moderates the effect of negative reviews on sales.

This study takes a multi-method approach in explaining the phenomenon, including an empirical analysis using secondary data from a movie review website and a movie box office website and a subsequent experimental study in a controlled experiment.

The findings of the study show that the effect of negative customer reviews on product sales is positive when the variance of customer reviews is large. Moreover, customers’ motivation to learn fully mediates the moderating effect of review variance on valence.

The findings provide vital managerial implications and suggest that managers should realize the important role of the review distribution.

This study mainly contributes to research on the negativity bias by identifying an important unexplored moderator and mediator and thus explains why negative customer review increases movie sales.

The purpose of this paper is to reveal the economic impact of policy reversals related to market liberalization reforms in China.

To perform the analysis, the authors hand-collect 59 financial market liberalization policy reversals from 1999 to 2017. These reversals are related to the liberalization of the stock market, bond market, derivatives market, forex market, lending market, and real estate market etc. The authors employ a stylized equilibrium interest rate model from Li et al. (2013) to deduce the impact of policy reversals on economic growth and the associated volatility after the announcement of each policy reversal.

First, the authors discover that about half of reversals are related to some tradeoff between the economic growth and the volatility associated with growth. Second, the authors also find that about a quarter of the reversals are detrimental to both the growth and the stability. These reversals, if known to policymakers, should be entirely avoided or corrected. Third, using a simple diagnostic test, the authors can identify detrimental reversals at the intra-day frequency by computing the change of the term spread and the volatility before and after the reversals.

The findings are useful for identifying effective policymaking in developing countries where mature democratic and rigorous policymaking processes are often lacking and formulating economic policies is challenging. The findings suggest that policy reversals serve China well by improving the quality of the policy made without posing destructive consequences to the existing economic infrastructure. This empirical evidence is important for a better understanding of the benefits of policy reversals on economic growth.

The empirical procedure provides a timely and objective evaluation of policy shifts, allowing for the general public to discern the rationale behind the policy decisions. Consequently, stakeholders’ trust and confidence in policymakers is enhanced so that the probability of the successful implementation of structural reforms may increase in these developing countries.

First, the results reveal some successful examples of Chinese policymaking in the path of liberalizing financial market. The authors find that the Chinese liberalization policy flip-flops have resulted in a more balanced growth on some occasions with reduced growth rate and volatility. Second, the proposed methodology provides an objective evaluation of policy shifts, allowing for the public to infer the general direction of the impact generated by policy shifts. Subsequently, stakeholders’ trust and confidence in policymakers can be enhanced and/or restored if the process of finding a successful path of structural reforms is unambiguous. Finally, the interest rate model also provides a timely method to evaluate the impact of policy shifts at an intra-day frequency, whereas most macroeconomic indicators are available at longer frequencies such as monthly or quarterly. The timeliness in understanding the economic consequences of policy reversals can be critical to prevent the destructive consequences of bad ones.

The purpose of this paper is to seek an efficient method to tackle the energy provision problem for smart grid with sparse constraints and distributed energy and storage devices.

A complex smart grid is first studied, in which sparse constraints and the complex make-up of different energy consumption due to the integration of distributed energy and storage devices and the emergence of multisellers are discussed. Then, a real-time pricing scheme is formulated to tackle the demand response based on sparse bilevel programming. And then, a bilevel genetic algorithm (BGA) is further designed. Finally, simulations are conducted to evaluate the performance of the proposed approach.

The considered situation is widespread in practice, and meanwhile, the other cases including traditional model without the sparse constraints can be seen as its extensions. The BGA based on sparse bilevel programming has advantages of “no need of convexity of the model.” Moreover, it is feasible without the need to disclose the private information to others; therefore, privacies are protected and system scalability is kept. Simulation results validate the proposed approach has good performance in maximizing social welfare and balancing system energy distribution.

In this paper, the authors consider the sparse constraints due to the fact that each user can only choose limited utility companies per time slot. In reality, there exist some other sparse cases, which deserve further study in the future.

To the best of the authors’ knowledge, this is one of the very first studies to address pricing problems for the smart grid with consideration of sparse constraints and integration of distributed energy and storage devices.

Considering two-dimensional features in the body shape classification system cannot fully reflect the three-dimensional (3D) morphological characteristics of human body. The purpose of this paper is to propose a 3D feature based method to characterize and classify the upper body shape of women, and then obtained the corresponding garment block and improved the fitness of clothing.

In this study, the [TC]² 3D scanner was used to obtain human data, and 15 layers of cross-sections of young females’ upper body were extracted. In total, 240 space vectors were obtained with the center of the bust cross-section as the original point. By using the principal component analysis and K-means clustering analysis, the body shape classification based on the space vectors length was realized. The garment block corresponding to three body types was obtained using the 3D scanning data and the cross-section convex hull, and compared with existing garment block and evaluated fitness of the blocks.

In total, 11 main components used to characterize the 3D morphological features of young women were obtained, which could explain 95.28 percent features of young women’s upper body. By cluster analysis, the body shape of women was divided into three categories. The block of three body types was obtained by the construction of the convex hull model.

This paper investigates a classification method of the body shape based on space vector length, which can effectively reflect the difference of surface shape of human body and further improve the matching degree of human body and clothing.

The purpose of this study was to prepare carboxylated attapulgite (APT-COOH) and then be used as one of the ligands to prepare metal organic framework (MOF) hybrid materials to reduce the cost of MOF materials and improve the dispersed condition of APT. And then the materials were used to enrich anionic dye Congo red from aqueous solution.

The MOF hybrid materials were designed by means of facile reflux method rather than hydrothermal method, characterized by Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectrometer and pore structure. The dispersed degree of APT-COOH in the MOF materials was validated according to adsorption efficiency for Congo red.

Due to introduction of APT-COOH, the microenvironment of the MOF materials changed, leading to different adsorption behaviors. Compared to the MOF material without APT-COOH, the adsorption capacities of the hybridized MOF materials with different amounts of APT-COOH introduced increased by 4.58% and 15.55%, respectively, as the initial concentration of Congo red solution of 300 mg/L. Meantime, hybridized MOF materials were suitable to remove Congo red with low concentration, while the MOF material without APT-COOH was appropriate to enrich Congo red with high concentration.

The microstructure of MOF hybrid materials in detail is the further and future investigation.

This study will provide a method to reduce the cost of MOF materials and a theoretical support to treat anionic dyes from aqueous solution.

APT-COOH was prepared and used as one of the ligands to synthesize MOF material to improve the dispersed degree of APT-COOH and reduce the cost of the MOF materials. The adsorption efficiency was greatly enhanced with low concentration of Congo red solution, and the results indicated that hydrogen bonding, electrostatic interaction, and p-p conjugation were involved in the adsorption process. The prepared MOFs materials exhibited excellent adsorption efficiency, which made the present materials highly promising and potentially useful in practical application as adsorbents to enrich anionic dyes such as Congo red from aqueous solution.