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This study aims to explain the market-oriented transformation dilemma of Chinese urban investment and development companies (UIDCs; also known as local government investment and financing companies) and objectively evaluate their transformation efficiency from both static and dynamic perspectives. The results of the research provide methodological bases for improving the transformation efficiency of UIDCs, thus pointing out the direction for the rational planning of their transformation path.

This study takes Chinese UIDCs in market transformation during 2015–2019 as the research object and uses principal component analysis to screen the index system for measuring the efficiency of market transformation. It then uses a three-stage data envelopment analysis model and the Malmquist productivity index to evaluate the market transformation efficiency of these companies during 2015–2019 and comprehensively analyzes the influence of external environmental factors on the market transformation of Chinese UIDCs.

Research results show that the transformation efficiency of Chinese UIDCs is low and slow overall and that large spatial and temporal differences exist. The transformation efficiency of UIDCs located in eastern China is higher than that of UIDCs in central and western China. The higher the external environmental factors of regional GDP, local debt service pressure and credit rating, the more likely they are to cause input redundancy in the transformation process of Chinese UIDCs, which is not conducive to their market-oriented transformation. In addition, the higher the urbanization rate, the more effective it is to improve the efficiency of market-oriented transformation of UIDCs. If the influence of environmental factors is stripped away, both the overall efficiency value and pure technical efficiency value of market-oriented transformation of Chinese UIDCs will increase while the scale efficiency value becomes smaller.

This research measures the transformation efficiency of Chinese UIDCs and comprehensively analyzes the influence of external environmental factors on their market-oriented transformation. The goal is to enrich the study of the market-oriented transformation efficiency evaluation index system of Chinese UIDCs at the theoretical level and provide important reference values for improving the efficiency of market-oriented transformation of Chinese UIDCs at the practical level.

Assembly Sequence Planning integrating assembly Resources (ASPR) is a trend in industry. Because of the introduction of resource, the complexity of ASPR for complex product increases drastically; besides, the dynamic property of resource and the co‐existence of assembly sequence and disassembly sequence (ASDS) make the problems in ASPR more difficult. The dynamic assembly model (DAM) based on polychromatic sets (PS) theory was proposed to address these issues.

First, a strategy was presented to simplify ASPR, taking advantage of assembly sequence generated in the phase of assembly design which considers no resource. Secondly, the concept of DAM was discussed, and some principles/criteria for DAM modeling were generalized from experience. Then, the DAM was modeled by formalizing its incidence relations as PS matrix, and refined based on the formalized criteria, which were expressed as PS locating and collision relation models. Finally, an application case was studied to demonstrate the effectiveness of the method.

The approach could reduce the complexity of ASPR significantly, and was able to identify dynamic resource, model DAM and handle the co‐existence of ASDS effectively.

The method may change the manual pattern of ASPR in simulation environment, and become a potential tool to change the pattern of traditional ASP which comes to work from scratch, by utilizing the upstream information of product design.

Different from traditional assembly model, DAM was a local model which consists of partial components of product and resource, and the DAM‐based ASPR approach would make the computational complexity of product assembly become more linear than exponential.

The purpose of this paper is to review land/real estate registration practice in Hong Kong, and make an in-depth comparison with Mainland China and finally provide helpful suggestions for the government.

Research methods including document analysis/review and comparative study are used in this paper.

The main findings focus on the problems existing in the mainland, including narrow query subject, single way of query, limited query time, and lacking of incentive mechanism. Helpful suggestions for real estate registration system in Mainland China are offered based on the comparative study.

The unified registration system can improve the efficiency of administrative institutions to ensure an open and transparent environment of property right registration, which helps prevent the relevant departments from abusing administrative power and harming the interests of obligees. The findings of this research can serve as a useful reference for policy makers to improve the unified registration system in China.

The registration system/mechanism determines the efficiency and effectiveness of real estate/land market. However, land registration and query in some countries such as Mainland China have institutional problems which hinder the sustained and healthy development of the real estate industry. The value of this paper is to propose constructive suggestions for such countries/regions by comparing and learning from a good model.

Due to environmental externalities, micro-enterprises with profit-seeking features do not develop sufficient motivation for environmental governance. In a fiscally decentralized system, local environmental protection authorities perform environmental supervision, and the intensity of the regulations that they implement has an important influence on corporate environmental governance. Based on the promotion tournament framework, this paper aims to discuss the driving mechanism of corporate environmental governance using turnover of environmental protection department directors (EPDDs) as an indicator.

Using samples of A-share companies listed on the Shanghai and Shenzhen exchanges from 2007 to 2014, this paper examines the impact of EPDD turnover on corporate environmental governance and its underlying mechanism.

The results show that corporate environmental governance exhibits a political periodicity that changes with the turnover of the EPDD, and the periodicity remains after controlling for the influence of changes in provincial party secretary and governor. Internal mechanisms analysis indicates that, without financial independence, local environmental protection departments rely on increasing sewage charges, not environmental protection subsidies, to promote corporate environmental governance. Further, considering heterogeneity among officials, it finds that the younger a new EPDD is, the more pronounced the periodicity of corporate environmental governance. However, there is no significant difference between in-system and out-system turnover.

In general, this paper describes the mechanisms of corporate environmental governance from the perspective of political economics, and the results have implications for the potential improvement of the government’s environmental supervision functions and the development of ecological civilization in China.

The purpose of this paper is to make an evaluation and early warning prediction using grey prediction models and the index of process ability.

An early warning prediction for food security risk is proposed in this paper. A quality index is constructed and an improved grey prediction model is also presented. The quality index model is applied to measure the level of food quality; then the grey prediction model is applied to predict the trend of quality index for food in the future. A comparison between the predicted trends and standard limit proposed by experts is made to judge the food security risk.

The results in this paper indicate that more attention should be paid to the food security situation and steps should also should be taken to prevent harm to people's health from food.

The method presented in the paper could be used to make predictions for those systems which have the characteristic of small sample and poor information. The combination of grey prediction model and process ability index could also be applied to evaluation and early warning for those systems.

Food quality index is constructed for evaluating food security and an improved grey prediction model is also presented in this paper. The combination of these two models could be applied to make evaluation and warning prediction for food security risk with poor information.

A public emission reduction project offers saleable carbon credits to encourage individual residents to participate in activities with low carbon emissions: if the residents participate, they will earn carbon credits that can be sold to polluting firms for carbon offsetting. This study explores the economic and environmental implications of these projects.

The authors develop a multiperiod model to incorporate the decisions of individual residents and a polluting firm. The model captures residents' difference in estimating the price of carbon credits: A proportion of residents are naive residents who shortsightedly take the previous market price of carbon credits as the basis of their decision-making.

A public emission reduction project can improve the cost-efficiency of carbon reduction, increase both the profit of the polluting firm and consumer surplus, but may hurt the welfare of the participating residents. Reducing transaction costs of carbon credits may cause a greater loss to participating residents. As the ratio of naive residents decreases, the overall welfare of participating residents increases and the number of participating residents decreases.

To encourage more residents to reduce carbon emissions, the project should be promoted to new areas (e.g. rural areas) where there are more naive residents. Although reducing transaction costs is an effective way to increase the economic viability of the project, the government should pay attention to protecting the welfare of residents, and educating residents is an effective way to improve their overall welfare.

This paper is the first to reveal the economic and environmental implications of public emission reduction projects.

The purpose of this paper is to clarify the effect of compressive stress on cavitation-erosion corrosion behavior of 304 stainless steel.

Compressive stresses of 60 MPa and 120 MPa were applied to 304 stainless steel through a self-designed loading device, and cavitation erosion-corrosion tests were performed using an ultrasonically vibratory apparatus. Scanning electron microscope and X-ray diffraction were used to analyze the microstructure evolution, and corrosion behavior was studied by electrochemical analysis.

The cavitation weight loss of 304 stainless steel decreased with the compressive stress. After cavitation corroded for 8 h, the weight loss for the specimen with 120 MPa compressive stress was 5.11 mg/cm², which was reduced by 56.7% from that of the specimen without loading stress (11.79 mg/cm²). The reason can be attributed to that compressive stress promoted the deformation-induced martensitic transformation during the cavitation process, which could not only provide a cushioning effect by absorbing cavitation impact energy but also improve the hardness of 304 stainless steel.

Compressive stress was found to restrain the cavitation damage on 304 stainless steel, and the corresponding mechanism was proposed.

This paper aims to investigate the electrochemical corrosion behavior of a five-layer Al alloy composites (4343/4047/3003/4047/4343) with a thickness of 0.2 mm in NaCl solution.

Electrochemical impedance spectroscopy, polarization curve and morphology analyses were used to study the corrosion behavior of the Al alloy composites from cross-sectional and plane directions.

The corrosion resistance of the surface from the plane direction was higher than that from the cross sections. Si-enrich particles were observed in the outer 4047/4343 layer, and AlFeCuMnBi phases were identified in the core 3003 layer. The galvanic coupling between the Si-enrich particle and the Al matrix accelerated the dissolution Al matrix.

This work lays the experimental foundation for corrosion mechanism of the Al alloy composite plate.

This paper aims to study the effect of chloride concentration on the properties of passive film formed on Q235 steel in simulated concrete pore solutions.

Mott–Schottky analysis and electrochemical impedance spectroscopy were used to study the passive film of Q235 steel in simulated concrete pore solution. X-ray photoelectron spectroscopy was used to analyze the composition of passive film on Q235 steel.

When the chloride concentration is below the chloride threshold value, open circuit potential (OCP) and Rct gradually increases and donor concentration (N_D) remains unchanged with the increasing immersion time. When the chloride concentration exceeds chloride threshold value, OCP and Rct decreases after a temporary increase and N_D increases. The linear region of the Mott–Schottky curve lost its linearity. The electrochemical process control step is changed from charge transfer control to oxygen diffusion control. As the chloride concentration increases, the FeO content in the passive film increases and the Fe₂O₃ content decreases. Chloride can destroy the outer layer of passive film and introduce impurities.

The effects of chloride and immersion time on the change process of passive films on Q235 steel in simulated concrete pore solution were studied using electrochemical methods. The mechanism of chloride destroying passive film was analyzed.

Near-surface mounted (NSM) fiber-reinforced polymer (FRP) rod is extensively applied in reinforced concrete (RC) structures. The mechanical performances of NSM FRP-strengthened RC structures depend on the bond behavior between NSM reinforcement and concrete. This behavior is typically studied by performing pull-out tests; however, the failure behavior, which is crucial to the local debonding process, is not yet sufficiently understood.

In this study, a three-dimensional meso-scale finite element method considering the cohesion and adhesion failures is presented to model the debonding failure process in pull-out tests of NSM FRP rod in concrete. The smeared crack model is used to capture the cohesion failures in the adhesive or concrete. The interfacial constitutive model is applied to simulate the adhesion failures on the FRP-adhesive and concrete-adhesive contact interfaces.

The present method is first validated by two simple examples and then applied to a practical NSM FRP system. This work studied in detail the debonding process, the bond failure types, the location of peak bond stress, the transmitting deformation in adhesive and the morphology of contact zone. The developed method provides a practical and convenient tool applicable for further investigations on the debonding mechanism for the NSM FRP rod in concrete.

A three-dimensional meso-scale finite element method considering the cohesion and adhesion failures is presented to model the debonding failure in NSM FRP-strengthened RC structures. The smeared crack model and the interfacial constitutive model are introduced to develop a convenient approach to analyze the failures in adhesive, concrete and related interfaces. The developed numerical method is applicable for studying the debonding process, the bond failure types, the location of peak bond stress, the transmitting deformation in adhesive and the morphology of contact zone in detail.