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Understanding the effect of process parameters on interfaces and interfacial bonding between two materials during multi-material additive manufacturing (MMAM) is crucial to the fabrication of high-quality and strong multi-material structures. The purpose of this paper is to conduct an experimental and statistical study to investigate the effect of process parameters of soft and hard materials on the flexural behavior of multi-material structures fabricated via material extrusion-based MMAM.

Sandwich beam samples composed of a soft core and hard shells are fabricated via MMAM under different printing conditions. A design of experiments is conducted to investigate the effect of the print speed and nozzle temperature on the flexural behavior of soft-hard sandwich beams. Analysis of variance and logistic regression analysis are used to analyze the significance of each process parameter. The interfacial morphology of the samples after the flexural tests is characterized. Thermal distributions during the MMAM process are captured to understand the effect of process parameters on the flexural behavior based on inter-bonding formation mechanisms.

Experimental results show that the soft-hard sandwich beams exhibited two different failure modes, including shell failure and interfacial failure. A transition of failure modes from interfacial failure to shell failure is observed as the nozzle temperatures increase. The samples that fail because of interfacial cracking exhibit a pure adhesive failure because of weak interfacial fracture properties. The samples that fail because of shell cracking exhibit a mixed adhesive and cohesive failure. The flexural strength and modulus are affected by the nozzle temperature for the hard material and the print speeds for both hard and soft materials significantly.

This paper first investigates the effect of process parameters for soft and hard materials on the flexural behavior of additively manufactured multi-material structures. Especially, the ranges of the selected process parameters are distinct, and the effect of all possible combinations of the process parameters on the flexural behavior is characterized through a full factorial design of experiments. The experimental results and conclusions of this paper provide guidance for future research on improving the interfacial bonding and understanding the failure mechanism of multi-material structures fabricated by MMAM.

This paper aims to conduct an empirical study to investigate whether an industry’s position affects the transmission of information and economic shocks.

This paper conducts an empirical study of inventory performance based on a large panel of 71 industries in the manufacturing, wholesale and retail sectors over a 10-year period (2007–2016).

It is found that the position of a focal industry in the supply chain network moderates the impacts of macroeconomic uncertainty shocks and shocks from supplier/customer industries on the focal industry’s inventory. On the one hand, more central industries are more sensitive to macroeconomic uncertainty shocks as well as spillover shocks from their supplier and customer industries. On the other hand, uncertainty shocks from more central industries have higher impact on their partner industries than those from less central industries.

A manager needs to take into account the network positions of suppliers/customers in supply network when making inventory decisions. For example, when sharing information with partners, the network position of a partner affects how important its information is.

The key novelty of this paper is the introduction of network structure that represents the supplier–customer relationships in the entire economy, and the modeling of uncertainty shocks transmitted through the supply chain network.

By introducing the mass customization service mode into the cloud logistics environment, this paper studies the joint optimization of service provider selection and customer order decoupling point (CODP) positioning based on the mass customization service mode to provide customers with more diversified and personalized service content with lower total logistics service cost.

This paper addresses the general process of service composition optimization based on the mass customization mode in a cloud logistics service environment and constructs a joint decision model for service provider selection and CODP positioning. In the model, the two objective functions of minimum service cost and most satisfactory delivery time are considered, and the Pareto optimal solution of the model is obtained via the NSGA-II algorithm. Then, a numerical case is used to verify the superiority of the service composition scheme based on the mass customization mode over the general scheme and to verify the significant impact of the scale effect coefficient on the optimal CODP location.

(1) Under the cloud logistics mode, the implementation of the logistics service mode based on mass customization can not only reduce the total cost of logistics services by means of the scale effect of massive orders on the cloud platform but also make more efficient use of a large number of logistics service providers gathered on the cloud platform to provide customers with more customized and diversified service content. (2) The scale effect coefficient directly affects the total cost of logistics services and significantly affects the location of the CODP. Therefore, before implementing the mass customization logistics service mode, the most reasonable clustering of orders on the cloud logistics platform is very important for the follow-up service combination.

The originality of this paper includes two aspects. One is to introduce the mass customization mode in the cloud logistics service environment for the first time and summarize the operation process of implementing the mass customization mode in the cloud logistics environment. Second, in order to solve the joint decision optimization model of provider selection and CODP positioning, this paper designs a method for solving a mixed-integer nonlinear programming model using a multi-layer coding genetic algorithm.

This paper examines the comparative corporate performance of logistics companies in Korea, China and Japan. Based on the annual data from the listed companies, the growth rate of Chinese companies has surpassed that of Korean and Japanese companies and has labeled China as the fastest growing economy. How ever, labor efficiency of Chinese firms when calculated by total revenue per employee is the lowest of the three countries. In addition, the profitability of Chinese multimodal logistics companies and sea transport companies is also lower than that of Korea and Japan.

Using Data Envelop Analysis(DEA), the primary results regarding corporate efficiency among Korean, Chinese and Japanese logistic companies are as follows: In the multimodal industries, Japanese firms have revealed the highest level of efficiency, with Korean firms coming in second, and Chinese firms ranking third with distinctly inferior performance. This trend has also been examined in the maritime industries, in which the efficiency levels have been deteriorating continuously. However, in the air transportation industry Chinese companies revealed the highest level of efficiency, which resulted from the business characteristics of the government supported conglomerate companies.

Preventing and tackling bullying effectively are important agenda for schools to safeguard all children’s well-being, engagement and sense of belongingness. Children perceived to be different from their peers tend to have a higher risk of being bullied at school, in particular, children with disabilities. It can be challenging for teachers to stop bullying that targets children with disabilities. This chapter considers bullying as a barrier to ensuring inclusive and quality education for everyone. It draws on findings from an ethnographic study concerning the status of inclusion of children identified as having learning difficulties in mainstream schools in China, by listening to what children and teachers have to say (Wang, 2016). The study found that the child participants were subject to forms of bullying. They found it useful to gain support from others when bullying happened, and they showed empathy towards peers’ well-being. The teacher participants reflected on the dilemmas and challenges of dealing with bullying and were keen to share experiences about what they found helpful in addressing the issue. The chapter discusses how insights about bullying learned from children and teachers can be used to inform the enactment of inclusive pedagogy. It is concluded that an inclusive pedagogical response that recognizes every child’s voice is necessary for tackling bullying and co-creating an inclusive environment.

The paper aims to explore the factors that influence the risk perception. The moderating roles of purchase experience and purchase involvement are also investigated.

The conceptual model is framed into the SOR (stimulus-organism-response) model, which was tested using data collected from the users of a leading group buying platform in China, with the help of LISREL.

The result indicates that both vendor- and intermediary-related factors exert negative yet significant influences on perceived risk. The relationships between vendor-related attributes and perceived risk are contingent on purchase involvement. The relationships between intermediary-related attributes and perceived risk are subject to purchase experience.

This study explores the moderating effects of purchase experience and purchase involvement based on the characteristics of group buying, demonstrating the differences from traditional online shopping.

The purpose of this paper is to analytically perform gaseous slip flow and heat transfer analysis within a parallel-plate microchannel partially filled with a centered porous medium under local thermal non-equilibrium (LTNE) condition. Heat transfer of gaseous flow in a porous microchannel is analytically studied. Energy communication at the porous-fluid interface is considered by two approaches: the gas rarefaction negatively impacts the heat transfer performance, and the optimum ratio of porous thickness is found to be around 0.8.

Both Models A and B are utilized to consider the heat flux splitting for the fluid and solid phases at the porous-fluid interface.

Analytical solutions for the fluid and solid phase temperature distributions and the Nusselt number are derived. In the no-slip flow limit, the present analytical solutions are validated by the partially and fully filled cases available in the literature.

The continuum flow (no-slip flow) is only a special case of the slip flow. Meanwhile, the effects of pertinent parameters on the heat transfer are also discussed.

A survey of available literature mentioned above indicates a shortage of information for slip flow and heat transfer in partially filled porous systems. The main objective of the present study is to investigate the slip flow and heat transfer characteristics for forced convection through a microchannel partially filled with a porous medium under LTNE condition. The porous substrate is placed at the center of the microchannel. Analytical solutions for the temperature distributions of the fluid and solid phases and the Nusselt number at the microchannel wall are obtained.

Heat transfer of gaseous flow in a porous microchannel is analytically studied. Energy communication at the porous-fluid interface is considered by two approaches: the gas rarefaction negatively impacts the heat transfer performance, and the optimum ratio of porous thickness is found to be around 0.8. Gaseous slip flow and heat transfer analysis is analytically performed within a parallel-plate microchannel partially filled with a centered porous medium under LTNE condition. Analytical solutions for the fluid and solid phase temperature distributions and the Nusselt number are derived for the first time. The effects of pertinent parameters on the heat transfer are also discussed. Compared with the results obtained for the continuum flow regime, the gas rarefaction negatively impacts the heat transfer efficiency and has little influence on the optimal porous thickness.

Faced with the challenges of rural population decline, combined with the widespread expansion of homesteads in rural areas, local Chinese governments hope to strictly control and minimize rural housing land. Accurately decomposing the process of rural housing expansion and revealing its driving factors will be helpful for land-use regulation by the government.

In this study, an unusually rich dataset of rural housing registration from Pudong New Area in Shanghai is employed. The study aimed to decompose the fragmented accumulation process and its expansion determinants on rural housing assets. The dataset covers all samples of rural households and housing plots at 72 surveyed villages in six towns.

Housing offers profitable capital and earning assets to villagers at the urban fringe, so they have a powerful incentive to build and expand more. The results of this analysis showed that the expansion of rural housing is largely due to the haphazard construction of auxiliary rooms by villagers, especially on plots of arable land that are adjacent to their houses that have been stealthily converted into auxiliary rooms and sheds. Low costs and weak penalties have led to an increase in rent-seeking expansions to rural houses. Houses with the smaller initial areas, families with more laborers and household heads, and the proximity of villages to downtown with convenient living services were the main driving factors for expanding houses. A concerted effort is needed to control the disorganized and unlicensed expansion of housing. This effort should include formulating areas for free use by villagers, high taxes on overused areas, serious penalties for unlicensed housing expansion and effective land-use planning.

An understanding of the expansion status and control measures related to rural houses in Shanghai provides an important reference that can help to guide the formulation of rural housing policies, and the sustainable development of cities worldwide. Of course, this study cannot generalize about housing distribution and expansion status worldwide based on the study area in China, because China's land tenure policies are unique. But land registry data exists that makes research like this feasible. There is a need to carefully examine the detailed housing distribution in each country before it can be decided on how best to address the disorderly increase in rural housing stock, and promote the reduction of rural residential expansion.

First, the process of rural housing expansion by using an unique dataset which covers ten thousands of samples is revealed. Second, the results have policy implications for reducing the amount of idle and inefficiently rural homestead. The focus is on rural housing growth and its driving factors in Shanghai, and the villagers' motivations for housing expansion are explored.

According to very small dimensions of the microchannels, producing a microchannel with smooth surfaces is approximately impossible. The surface roughness can have a specific effect on microchannel performances. This paper aims to investigate the changes in friction and pressure drop in the microchannels by considering the different roughness elements on microchannel wall and changes in elementary geometry and flow conditions. Results show a significant effect of roughness on the pressure drop and friction.

Two-dimensional fluid flow in the rough microchannels is analyzed using FLUENT. Microchannels have a height of 50 µm. Water at room temperature (25°C) has been used as working fluid. The Reynolds numbers are considered in laminar flow range and from 50 to 300.

The results show that the value of friction factor reduces nonlinearly with an increase in Reynolds number. But, the pressure drops and the Poiseuille number in the microchannels increase with an increase in Reynolds number. The values of the pressure drop and the friction factor increase by increasing the height and size of the roughness elements, but these values reduce with an increase in the distance of roughness elements.

The roughness elements types in this research are rectangular, trapezoidal, elliptical, triangular and complex (composed of multiple types of roughness elements). The effects of the Reynolds number, roughness height, roughness distance and roughness size on the pressure drop and friction in the rough microchannels are investigated and discussed. Furthermore, differences between the effects of five types of roughness elements are identified.

This paper aims to investigate whether a complementary effect exists between government R&D subsidies (GRSs) and intellectual property rights (IPR) protection on innovation performance in the pharmaceutical manufacturing industry in China. This paper also attempts to understand whether this complementary effect is significantly different across China’s eastern, central and western regions.

The study sample comprised 28 provinces involved in the pharmaceutical manufacturing industry in China from 2003 to 2014. Ordinary least squares was used to test the complementary effects of GRSs and IPR protection on innovation performance. The seemingly unrelated estimation test was also applied to ascertain whether differences existed between the eastern and western regions.

A complementary effect between GRSs and IPR protection in terms of improving the innovation of pharmaceutical manufacturers was found to exist only in eastern and western regions. There was no significant difference in the complementary effect between GRSs and IPR protection in terms of improving innovation among the three regions. Without considering the interaction effect of GRSs and IPR protection, the GRSs were negatively associated with innovation in the eastern region, but positively related to the innovation in central region.

This study contributes to the literature on government policies and innovation by incorporating the interaction effect of GRSs and IPR protection on innovation in the context of a high-tech industry (pharmaceutical manufacturing) in an emerging economy (China). It also explores the internal differences in the influence of this complementary effect on innovation in an emerging economy, enriching the institution-based view.