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Inter-organizational collaboration is the organizational guarantee and key link to achieve the goals of megaproject management. Project governance has always played an important role in the construction of megaprojects, but the relationship between project governance and organizational collaboration is unclear. The purpose of this study is to explore the role paths of different project governance mechanisms in influencing the collaborative behaviors of stakeholders and collaborative performance and to elucidate the mechanism of project governance on inter-organizational collaboration.

A conceptual framework was developed based on a comprehensive literature review, termed the structural equation model (SEM). The hypotheses of the model were tested based on data obtained from a questionnaire survey of 235 experts with experience in megaprojects within the construction industry in China.

The results show that project governance positively contributes to the collaborative behavior of megaproject stakeholders and the collaborative performance of the project team. Collaborative behavior acts as a partial mediator between project governance and the collaborative performance of the megaproject inter-organization alliance. The complexity of the project modulates the relationship between the governance mechanism of the project and the collaborative behavior of the stakeholders, which affects the collaborative performance of the megaproject inter-organization alliance.

The findings provide theoretical and practical implications for promoting positive collaborative behavior among stakeholders in megaproject selection and improving the collaborative performance of megaproject inter-organization alliances.

The purpose of this paper is to design a robust tracking algorithm which is suitable for the real-time requirement and solves the mistake labeling issue in the appearance model of trackers with the spare features.

This paper proposes a tracker to select the most discriminative randomly projected ferns and integrates a coarse-to-fine search strategy in this framework. First, the authors exploit multiple instance boosting learning to maximize the bag likelihood and select randomly projected fern from feature pool to degrade the effect of mistake labeling. Second, a coarse-to-fine search approach is first integrated into the framework of multiple instance learning (MIL) for less detections.

The quantitative and qualitative experiments demonstrate that the tracker has shown favorable performance in efficiency and effective among the competitors of tracking algorithms.

The proposed method selects the feature from the compressive domain by MIL AnyBoost and integrates the coarse-to-fine search strategy first to reduce the burden of detection. This paper designs a tracker with high speed and favorable results which is more suitable for real-time scene.

The mega railway infrastructure projects are faced with complex environments and multi-level management challenges. Thus, the mega railway infrastructure project management system not only needs to focus on its composition, but also needs to consider changes and impacts of internal and external environment.

This study attempts to introduce the concept of dissipative structure from the perspective of complexity theory and constructs a positive entropy and negentropy flow index system for mega railway infrastructure project management system in order to analyze the factors of management system more deeply. The Brusselator model is used to construct the structure of the mega railway infrastructure project management system, and the entropy method is used to calculate the positive entropy and negentropy values to verify whether the management system is a dissipative structure.

A plateau railway project in China was used as an example for an empirical study, not only its own characteristics are analyzed, but also the role of constraints and facilitation of the internal and external environment. Based on the research results, several effective suggestions are put forward to improve the stability and work efficiency of mega railway infrastructure project management system.

This study demonstrates that mega railway infrastructure project management system has the characteristics of dissipative structure. It can provide theoretical support for the development of mega railway infrastructure project management system from disorderly state to orderly state.

What is the relation between the land system with Chinese characteristics and the country's high-speed economic growth in the past decades? There is a lack of rigorous academic research based on the general equilibrium theory of macroeconomics on this issue.

By building a multisector dynamic general equilibrium framework with land system, this paper explores how the land supply mode with Chinese characteristics affects China's economic growth as well as its transmission mechanism.

This paper confirms the importance of land system with Chinese characteristics in explaining the mystery of China's high-speed economic growth. Counterfactual analysis shows that if China adopts a land system similar to that of other developing countries, GDP will drop 36% from the current level under the baseline model.

As the industrial sector shrinks relatively and the output elasticity of infrastructure decreases, this inhibitory effect will become more apparent. China should improve its land supply mode, especially expand the supply of commercial and residential land and reduce the cost of land in the service sector. This can promote better economic development in the future and thus improve household welfare and the structure of aggregate demand, replace “land-based public finance” and thus inhibit the “high leverage” risks of local governments.

Corn, which has the highest domestic production, planting area and consumption, is the top cereal in relation to demand and supply in China. However, the comparative advantage of China in corn has continuously deteriorated in recent years and based on the recent situation and possible supply and demand trends, it is widely accepted that a corn self-sufficiency rate of 95% is difficult to achieve. Under current import-restriction policies, corn may stand at the crossroads of reforms to solve its predicted insufficient supply. In this study, the authors analyse the necessity of relaxing trade restrictions on corn in China and explore the effects of trade restrictions by reducing tariffs and expanding tariff-rate quotas on corn and related industries and the welfare change caused by possible relaxations.

The authors construct a computable general equilibrium (CGE) model and design nine scenarios for the analysis.

The results show that relaxations of import restrictions are probable methods to meet the aim of sufficient corn supply during shortages. They are simulated to reduce corn's domestic production and price, increase import and import prices and lead to a decline in self-sufficiency but benefit the production of corn-related industries of corn. The results also imply that expanding the quota is a better method for releasing trade restrictions in China.

The comparative advantage of China in corn deteriorated with an increase in prices. Based on the current situation and possible trends of supply and demand, the referenced goal of achieving 95% corn self-sufficiency appears difficult, implying that reliance on imports is probably imminent and vital. This study provides simulation results in future scenarios and offers policy implications for China's corn trade policies.

The purpose of this paper is to investigate the unsteady aerodynamic characteristics in the deflection process of a morphing wing with flexible trailing edge, which is based on time-accurate solutions. The dynamic effect of deflection process on the aerodynamics of morphing wing was studied.

The computational fluid dynamic method and dynamic mesh combined with user-defined functions were used to simulate the continuous morphing of the flexible trailing edge. The steady aerodynamic characteristics of the morphing deflection and the conventional deflection were studied first. Then, the unsteady aerodynamic characteristics of the morphing wing were investigated as the trailing edge deflects at different rates.

The numerical results show that the transient lift coefficient in the deflection process is higher than that of the static case one in large angle of attack. The larger the deflection frequency is, the higher the transient lift coefficient will become. However, the situations are contrary in a small angle of attack. The periodic morphing of the trailing edge with small amplitude and high frequency can increase the lift coefficient after the stall angle.

The investigation can afford accurate aerodynamic information for the design of aircraft with the morphing wing technology, which has significant advantages in aerodynamic efficiency and control performance.

The dynamic effects of the deflection process of the morphing trailing edge on aerodynamics were studied. Furthermore, time-accurate solutions can fully explore the unsteady aerodynamics and pressure distribution of the morphing wing.

This paper aims to investigate the situation and evolution of sustainability performance in China.

This paper adopts the global Malmquist-Luenberger (GML) productivity index based on data envelopment analysis and Tobit regression for analysis.

The results indicate the following: China’s sustainability performance has been improving since 2005 and is closely related to the national development strategy and supportive policy; regional gaps in sustainability are a prominent problem represented by the fact that South Central China is becoming a sustainability collapse zone; interprovincial heterogeneity is evident with the varying development speed and conditions; and the level of sustainability performance has a significantly positive correlation with the urbanization rate, investment completed in the treatment of industrial pollution, government appropriation for education and per capita area of paved roads, but it has a negative correlation with the possession of private vehicles.

As an application, this study assessing the GML productivity index of 30 provinces in China from 2005 to 2015 and analyse the sustainability performance on three regional levels (i.e. country level, regional level and provincial level). Tobit regression is also applied to recognize the factors related to the GML index with the results taken as references for policy suggestions. The results have implications for a comprehensive understanding of China's sustainability performance and policymaking in this field.

The purpose of this paper is to compare the Armington elasticities for world average values and country-specific values and obtain evidence for whether the world average elasticities and the “rule of two”, which have been applied in many papers, are accurate for cereals in trade policy studies related to an individual country.

The authors use panel data with a nested model to estimate and compare Armington elasticities based on world average values and country-specific values from 10 countries and regions.

The results suggest that cereals’ elasticities vary between world average values and country-specific values, and the “rule of two” is not strictly applicable. In fact, the “less than two” concept fits well in many cases.

This study sheds light on the effects of country heterogeneity on the elasticities and the accuracy of using world average elasticities in a trade policy study for an individual country. In addition, this paper offers estimated values of country-specific elasticities for 10 countries and regions.

As in real applications several alternating current (AC) currents may be injected to the electronic devices, this study aims to analyze their effects on the lifetime of the solder joints and, consequently, shed the light on these effects at the design phase for other researchers to consider.

In this paper, the authors investigated on current waveform shapes on the performance and reliability of the solder joints in electronic package. Three common and extensively used current shapes in several simulations and experiments were selected to study their effects on the solder joint performance.

The results demonstrate a sever thermal swing and stress fluctuation in the solder joint induced in the case of triangle current type because the critical states lack any relaxation time. In fact, the stress intensification in the solder under application of the triangle current type has been shown to contribute to increasing brittle intermetallic compounds. An accelerated increase of on-state voltage of power semiconductor was also observed in under application of the triangle current type.

The originality of this paper is confirmed.

Urban parks play a key role in recreational activities, public health, and ecosystem services in urban areas. Using GIS and Fragstats, this study investigated the spatiotemporal dynamics of urban parks in Xi'an, China from 1949 to 2015 and the corresponding driving forces. The results show that the number and area of parks in Xi'an increased constantly during this period, especially from 2000 to 2015. Up to 2015, small green spaces, usually adjacent to streets, occupied the largest proportion among all types of parks. Archaeological parks were the largest in total area, but wetland parks were leading in average size of a single park. The density of parks was negatively correlated with their distance to the Clock Tower at the center of Xi'an. The dynamics of urban parks in highly urbanized areas were significantly different from that of their counterparts in suburban areas. Driving forces such as urban planning, urbanization and green space policies, and milestone events in the city's development jointly had a great effect on the distribution of parks in Xi'an. The research outcomes will support the upcoming Green Space Planning of Xi'an and benefit the pursuit of sustainability and human wellbeing.