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The purpose of this paper is to put forward countermeasures to ensure China's energy security based on an analysis of the world energy security situation and challenges China faces in the future in terms of energy security.

An induction approach is adopted to analyze the energy security situation of the world and that of China.

Although available energy resources can meet the medium and long‐term global energy demand, the world energy security faces lots of severe challenges in the aspects of demand and supply factors, infrastructure, geopolitics and strict environmental protection requirements, etc. China's energy supply security faces many challenges in the coming 20 ∼ 30 years or even in the long term. Taking external factors into consideration, the primary challenge is to ensure a stable and sustainable oil supply with reasonable prices. Though the external conditions are of great importance to China's energy security, the influences of domestic factors also need to be well recognized. With energy resources supply being the bedrock of energy security, the establishment of domestic energy market system and energy management framework will exert momentous impact upon the energy security. In addition, while the petroleum supply security is emphasized, attentions should at the same time be paid to the supply security of other energy products, especially to the supply of China's fundamental energy resource of coal.

The paper provides useful and timely analysis of world energy resources, world energy security situation and world economic performances.

The assumption that the family migrates as a unit downplays migrants’ circularity. This chapter focuses on China's rural–urban labor migrants that travel back and forth between the sites of work and home community and between places of work. I argue that migrants and their households pursue work flexibility in order to obtain the best of the urban and rural worlds, by gaining earnings from urban work and at the same time maintaining social and economic security in the countryside. Work flexibility demands flexibility in household organization, in the form of division of labor and collaboration between genders, generations, and households. Based on a study in Sichuan, I examine household biographies and narratives to identify migrants’ work and household strategies.

Migrants change jobs frequently, switch from one type of work to another and one location to another readily, and often return to the home village for months or even years before pursuing migrant work again. Not only are migrants ready to split the household between the city and the countryside, but also they frequently change from one form of division of labor to another. The inside–outside model, where the wife stays in the village and the husband does migrant work, used to be the dominant arrangement. Over time, the outside–outside model, where both the husband and wife migrate to work and leave behind other family members, is increasingly popular. This is facilitated by intergenerational and interhousehold division of labor in the form of assistance by the extended family. Intergenerational division of labor takes place when the second generation is replacing the parents in migrant work. This research's findings support the notion that rural–urban migrants are fast becoming a hybrid segment of Chinese society, playing dual roles of farmers and urban workers and straddling the peasant and urban worlds.

The long-span continuous rigid-frame bridges are commonly constructed by the section-by-section symmetrical balance suspension casting method. The deflection of these bridges is increasing over time. Wet joints are a typical construction feature of continuous rigid-frame bridges and will affect their integrity. To investigate the sensitivity of shear surface quality on the mechanical properties of long-span prestressed continuous rigid-frame bridges, a large serviced bridge is selected for analysis.

Its shear surface is examined and classified using the damage measuring method, and four levels are determined statistically based on the core sample integrity, cracking length and cracking depth. Based on the shear-friction theory of the shear surface, a 3D solid element-based finite element model of the selected bridge is established, taking into account factors such as damage location, damage number and damage of the shear surface. The simulated results on the stress distribution of the local segment, the shear surface opening and the beam deflection are extracted and analyzed.

The findings indicate that the main factors affecting the ultimate shear stress and shear strength of the shear surface are size, shear reinforcements, normal stress and friction performance of the shear surface. The connection strength of a single or a few shear surfaces decreases but with little effect on the local stress. Cracking and opening mainly occur at the 1/4 span. Compared with the rigid “Tie” connection, the mid-span deflection of the main span increases by 25.03% and the relative deflection of the section near the shear surface increases by 99.89%. However, when there are penetrating cracks and openings in the shear surface at the 1/2 span, compared with the 1/4 span position, the mid-span deflection of the main span and the relative deflection of the cross-section increase by 4.50%. The deflection of the main span increases with the failure of the shear surface.

These conclusions can guide the analysis of deflection development in long-span prestressed continuous rigid-frame bridges.

An alliance portfolio can help latecomer firms to acquire the necessary knowledge and resources to catch up with market leaders. However, how latecomer firms construct an alliance portfolio in terms of the nature of windows of opportunity has not been fully analyzed. This paper aims to explore how latecomer firms can build appropriate coalitions according to the nature of the window of opportunity to achieve technological catch-up in different catch-up phases.

Based on a longitudinal case study from 1984 to 2018 of Sunny Group, now a leading manufacturer of integrated optical components and products, this paper explores the process of technological catch-up of latecomer firms building different types of alliance portfolio in different windows of opportunity.

This paper finds that there is a sequence when latecomers build an alliance portfolio in the process of catch-up. When the uncertainty of opportunity increases, the governance mechanism of the alliance portfolio will change from contractual to equity-based. Also, latecomer firms build market-dominated and technology-dominated alliance portfolios to overcome their market and technology disadvantages, respectively.

These conclusions not only enrich the theory of latecomer catch-up from the perspective of windows of opportunity but also expand research on alliance portfolio processes from a temporal perspective.

Considering the role of analysts in disseminating information, the paper explains the idiosyncratic volatility puzzle of China's stock market. As the largest developing country, China's research can provide meaningful reference for the research of financial markets in other new countries.

From the perspective of behavior, establishing a direct link between individual investor attention and stock price overvaluation.

The authors find that there is a significant idiosyncratic volatility puzzle in China's stock market. Due to the role of mispricing, individual investor attention significantly enhances the idiosyncratic volatility effect, that is, as individual investor attention increases, the greater the idiosyncratic volatility, the lower the expected return. Attention can explain the idiosyncratic volatility puzzle in China's stock market. In addition, due to the role of information production and dissemination, securities analysts can reduce the degree of market information asymmetry and enhance the transparency of market information.

China is the second largest economy in the world, and few scholars analyze it from the perspective of investors' attention. The authors believe this paper has the potential in contributing to the academia.

The purpose of this paper is to demonstrate the influence of annealing treatment on the photovoltaic properties of the solar cell based on ITO/PEDOT:PSS/ZnO:P3HT/Ag.

The influence of the annealing temperature and time on the P3HT/ZnO interface morphology and the ITO/PEDOT:PSS/ZnO:P3HT/Ag solar cell performance was discussed. The morphology and the current‐voltage (J‐V) characteristics were investigated by atomic force morphology (AFM) and solar simulator with an AM 1.5 G filter under an irradiation intensity of 100 mW cm⁻². The light intensity was calibrated using a standard silicon photovoltaic solar cell.

The photovoltaic performances were found to have been greatly enhanced by an annealing treatment at 145°C for 30 min.

The paper demonstrates that the annealing treatments play a crucial role in improving the morphology and J‐V performance of the ITO/PEDOT:PSS/ZnO:P3HT/Ag solar cell.

Scholars have examined the relationship between sports and urban development and proposed to use sport programs and events as a catalyst to revitalize communities, upgrade urban infrastructure, promote city image, shift economic structure, nurture an active lifestyle, and enhance societal harmony and solidarity. Yet, previous studies were usually focused on mega sport events and were typically conceptual, theoretical and lack of practical applications. This study was designed to attain in-depth understanding on how a specific sport, table tennis, can be systematically organized and utilized to influence urban development through a qualitative research injury.

This investigation was carried by conducting in-depth interviews of the executive director of the Shanghai Table Tennis Association, on-site observations and comprehensive review of literature. Development of interview questions took into consideration the conceptual framework postulated by Preuss (2007) that contains six structures of urban development through sports. Triangulation analyses were conducted to cross validate the three information sources to generate themes and assertions.

While the identified practices were consistent with Preuss' (2007) framework, specific management activities earnestly practiced in Shanghai are centered on utilizing cultural and historical heritage, star power, branding strategies, staging tournaments, hallmark events, technical innovation and government relations to achieve the objectives of table tennis as a sport and the objectives of urban development through table tennis.

The findings of this study help fill the void that a theory usually cannot specify, namely, detailed, unambiguous practices. While table tennis may be a viewed as a small sport in many parts of the world, it has a strong, unprecedented historical heritage in Shanghai. This city has made a prudent choice and investment in this sport, which has proved to be effective. Other cities in the world should look into their own social, cultural and historical heritage and develop sport strategies, operations and programs accordingly.

The paper aims to evaluate the influence of atmospheric environment on the conductivity of nanoscale copper films sputtered on polyester substrates; process parameters of optimal conductivity were firstly analyzed by orthogonal test scheme design, and then the surface morphology, crystal structures and conductivity of samples were performed after samples were placed in the atmospheric conditions for some time according to the optimization of process parameters.

Nanoscale copper films was prepared by RF (radio frequency) magnetron sputtering and low-temperature plasma technology with polyester fabrics as substrates and metal copper as targets under the conditions of low temperature and high vacuum.

The experimental results showed that copper films were broken and the continuity of samples was destroyed after 60 days, while exposed in atmospheric environment for 90 days, cracks of copper films gradually expanded, there was no change in the atomic species for samples placed in the atmospheric conditions. However, the conductivity of the samples hardly had changed with the ambient temperature, humidity and degree of water washing, which is mainly decided by the internal structures of substrates.

This paper has some theoretical and applicable value to the functional textile.

The purpose of this paper is to discuss polyester fabric structures in terms of the surface morphology, crystal structure of copper films and interfacial bonding properties between polyester fabrics and copper films.

Nanoscale copper (Cu) thin films were deposited onto the surface of polyester fabrics with different structures by the radio frequency magnetron sputtering technique at room temperature.

Copper films uniformly deposited on the surface of the polyester nonwovens and nanofiber membranes have larger average particle diameters and surface roughness, and higher crystallinity.

Theoretical value: the effects of polyester substrate structures on the morphology and interfacial bonding properties of Cu thin films have rarely been reported.

A new deviation propagation model considering the form defects in compliant assembly process is proposed. The purpose of this paper is to analyze the deviation propagation by using the basic deviation fields. In particular, each basic deviation field is defined with a generalized compliance matrix of part.

First, the form defects of parts may be decomposed into a linear combination of basic deviation fields, which are constructed by the eigen-decomposition of the structure stiffness of parts with ideal dimensions. Each basic deviation field is defined with a generalized compliance of part. Moreover, by analyzing the relationship between the basic deviation fields before and after assembling process, a new sensitive matrix is obtained in which each value expresses the correlation of a basic deviation field between the parts and the assembly.

This model may solve the deviation propagation problems of compliant assembly with considering form defects. Here, one case is used to illustrate the deviation propagation in the assembly process. The results indicate that the proposed method has higher accuracy than the method of influence coefficient when the entire deviation fields of parts are considered. Moreover, the numerical results with the proposed method basically agree with the experimental measurements.

Owing to the hypothesis of linear superposition of basic deviation fields, the research in this paper is limited to the parts with linear elastic deformation. However, the entire form defects of parts are considered rather than the deviations of the local feature points. It may be extended to analyze the three-dimensional deviations of complex thin-walled parts.

A deviation propagation model considering parts form defects is developed to achieve more accurate predictions of assembly deviation by using the basic deviation fields.