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This study aims to focus on the effect of interlayer bonding and thermal decomposition on the mechanical properties of fused filament fabrication-printed polylactic acid specimens at high extrusion temperatures.

A printing process, that is simultaneous manufacturing of contour and specimen, is used to improve the printing accuracy at high extrusion temperatures. The effects of the extrusion temperature on the mechanical properties of the interlayer and intra-layer are evaluated via tensile experiments. In addition, the microstructure evolution affected by the extrusion temperature is observed using scanning electron microscopy.

The results show that the extrusion temperature can effectively improve the interlayer bonding property; however, the mechanical properties of the specimen for extrusion temperatures higher than 270°C may worsen owing to the thermal decomposition of the polylactic acid (PLA) material. The optimum extrusion temperature of PLA material in the three-dimensional (3D) printing process is recommended to be 250–270°C.

A temperature-compensated constitutive model for 3D printed PLA material under different extrusion temperatures is proposed. The present work facilitates the prediction of the mechanical properties of specimens at an extrusion temperature for different printing temperatures and different layers.

Teaching by demonstration (TbD) is a promising way for robot learning skills in human and robot collaborative hybrid manufacturing lines. Traditionally, TbD systems have only concentrated on how to enable robots to learn movement skills from humans. This paper aims to develop an extended TbD system which can also enable learning stiffness regulation strategies from humans.

Here, the authors propose an extended dynamical motor primitives (DMP) framework to achieve this goal. In addition to the advantages of the traditional ones, the authors’ framework can enable robots to simultaneously learn stiffness and the movement from human demonstrations. Additionally, Gaussian mixture model (GMM) is used to capture the features of movement and of stiffness from multiple demonstrations of the same skill. Human limb surface electromyography (sEMG) signals are estimated to obtain the reference stiffness profiles.

The authors have experimentally demonstrated the effectiveness of the proposed framework. It shows that the authors approach could allow the robot to execute tasks in a variable impedance control mode with the learned movement trajectories and stiffness profiles.

In robot skill acquisition, DMP is widely used to encode robotic behaviors. So far, however, these DMP modes do not provide the ability to properly represent and generalize stiffness profiles. The authors argue that both movement trajectories and stiffness profiles should be considered equally in robot skill learning. The authors’ approach has great potential of applications in the future hybrid manufacturing lines.

In today’s Taiwan, sha-cha sauce is an indispensable ingredient for beef hot pot and stir-fried dishes. The purpose of this paper contextualizes the history of sha-cha sauce in Tainan, the oldest city in Taiwan, and argues that sha-cha sauce, introduced by Chaoshan immigrants, has contributed to new styles and habits of beef consumption tastes and habits in the post-1949 Tainan and beyond.

This paper uses documentary materials, oral interviews and diaries to explore the relationship between beef consumption and sha-cha sauce. It begins with an historical overview of Taiwan’s beef consumption during the Japanese colonial era (1895-1945). Then, it focuses on two Chaoshan business enterprises: the Bull-Head, which makes the world’s largest “canned sha-cha sauce,” and the Xiao Haozhou, a Tainan restaurant specializing in sha-cha beef hot pot. Finally, this study analyzes Xinrong Wu, a Tainan gentry whose diary entries from 1933 to 1967 documented the changing dietary habits of beef consumption among Taiwanese.

The Chaoshan migrants played an important role in introducing the sha-cha sauce to postcolonial Tainan, and this input bolstered the beef consumption among Taiwanese. The production of sha-cha provided a reliable source of income for these migrants in Tainan, and major businesses like the Bull-Head became the international brands of Taiwanese food products.

The study, though limited to Tainan, reveals the symbiosis between popularization of sha-cha sauce and widespread beef consumption in Taiwan.

This study helps researchers examine the connection between Chinese migrations and food culture.

This paper is an original scholarly investigation of the relationship between food diet and Chaoshan migration in postcolonial Tainan.

The Incheon Region has numerous assets that fall within a Pentaport model.' These include the Incheon International Airport, the Port of Incheon, a coastal industrial park, free economic zones, a leisure port, and Songdo new town designed to be the future Silicon Valley of Korea. This paper looks at how Northeast Asia trade flows between China and Korea might be enhanced by application of the Pentaport model in making the Incheon region a North East Asian Hub. It looks also at their trade and logistics systems as well as their water borne commerce. It proposes an integrated transportation system for the Yellow Sea Region being beneficial to the economies of the Northeast Asia. It also stresses that innovative technologies for ships, terminals and cargo handling systems should be introduced to develop a competitive short sea shipping system in the region and cooperation among the regional countries will be essential to achieve the final goal. The potential of methods of container shipping is discussed as it might apply to short sea shipping in the Yellow Sea Region that could greatly facilitate Incheon's situation with respect to the broader region in application of the Pentaport model.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

In the 21^st Century, a region 's growth and prosperity will depend upon its intermodal transportation infrastructure and its ability to efficiently move goods, materials, and people within the system whether it be from origin to destination; from supplier to customer through the various levels of the supply-chain; or from point to point within the system. Planning for the future focuses on improving a region 's intermodal transportation system efficiencies and infrastructure, its connection to other economies, and on the development of logistics institutions and facilities.

With China 's rapidly developing economy and society, record numbers of new modern facilities such as airports, ports, highways, logistics parks and warehouses are being built. Along with this, companies have made extensive investments in information technologies and software to support the tremendous growth that has taken place in the logistics industry. The development and improvement of China's historic inland water transport system is essential to their continued future growth and prosperity. In Korea, past and present National Governments have emphasized the importance of developing a North East Asian Logistics and Business Hub in their region and have worked on strategies, which include water transport, as part of an important national agenda to that end.

This article looks at how trade flows in the Yangtze and Yellow Sea Regions and between China and South Korea might be enhanced by application of improved shipping methods in marine commerce that will promote economic growth in the region. The application of logistics practices and use of barges is explored for the movement of containers on inland and coastal waterways as well as in short sea shipping which could greatly facilitate the region 's situation with respect to future economic growth.

This study aims to simultaneously enhance the load-carrying capacity and control the leakage rate of mechanical seals by optimizing the texture shape.

A multi-objective optimization approach is implemented to determine the optimal “free-form” textures and optimal circular dimples. Experiments are conducted to validate the simulation results.

The experimental coefficient of friction (COF) and leakage rate are in good agreement with the calculated results. In addition, the optimal “free-form” texture shows a lower COF and a lower leakage in most cases.

This work provides a method to optimize the surface texture for a better combination performance of mechanical seals.

The purpose of this paper is to analyse the innovation effort underway in China to develop domestic technological capacity for the manufacturing of a low‐carbon energy technology: solar photovoltaics (PV).

A framework for analysis based on the “technological capability” (TC) literature was developed and applied to explore the innovative capacities and performance of the Chinese PV manufacturers. The paper draws on a survey conducted in China in mid‐2005 with a selected number of PV manufacturers, as well as on personal interviews with other Chinese PV stakeholders and international experts.

The paper shows that by 2005 PV firms in China had progressed well beyond basic operational capabilities and were quickly moving away from being mere users of imported PV components. Despite the existence of considerable differences between the firms, their competitiveness extended beyond the use of relatively cheap labour to the reduction of production costs through TC improvements. The paper recognises that the Chinese firms had developed innovation capacity only in the most mature PV technology family, i.e. crystalline silicon, which could leave them vulnerable if new PV technology families takeover. Moreover, the Chinese Government has not so far chosen to build upon its dynamic low‐carbon PV industry by promoting long‐term measures for the development of the domestic PV market. Consequently, challenges remain for the industry.

There has been limited previous research into China's capacity for PV innovation, how it is developing and how it might be improved. The paper shows that a better understanding of these aspects has important bearings on China's low‐carbon future and on potential development of a significant export industry.

The late incorporation of Lao PDR in the globalized age as an agricultural producer and exporter has been created through the process of “peasantization” and restructuring of agricultural upland productive area. The chapter discusses the role of the state and cross-border markets through contract farming in three villages in northern Lao PDR. Contrary to the general belief that economic globalization will result in the weakening of the state, the chapter argues that the state still has a significant role to play. Being late in the corporation into the world market, the changes that take place become very intense.