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The purpose of this paper is to design a low-power human physiological parameters monitoring system which can monitor six vital parameters simultaneously based on wearable body sensor network.

This paper presents a low-power multiple physiological parameters monitoring system (MPMS) which comprises four subsystems. These are: electrocardiogram (ECG)/respiration (RESP) parameters monitoring subsystem with embedded algorithms; blood oxygen (SpO₂)/pulse rate (PR)/body temperature (BT)/blood pressure (BP) parameters monitoring subsystem with embedded algorithms; main control subsystem which is in charge of system-level power management, communication and interaction design; and upper computer software subsystem which manipulates system function and analyzes data.

Results have successfully demonstrated monitoring human ECG, RESP, PR, SpO₂, BP and BT simultaneously using the MPMS device. In addition, the power reduction technique developed in this work at the physical/hardware level is effective. Reliability of algorithms developed for monitoring these parameters is assessed by Fluke Prosim8 Vital Signs Simulators (produced by Fluke Corp. USA).

The MPMS device provides long-term health monitoring without interference from normal personal activities, which potentially allows applications in real-time daily healthcare monitoring, chronic diseases monitoring, elderly monitoring, human emotions recognization and so on.

First, a power reduction technique at the physical/hardware level is designed to realize low power consumption. Second, the proposed MPMS device enables simultaneously monitoring six key parameters. Third, unlike most monitoring systems in bulk size, the proposed system is much smaller (118 × 58 × 18.5 mm3, 140 g total weight). In addition, a comfortable smart shirt is fabricated to accommodate the portable device, offering reliable measurements.

With the continuous development of the global COVID-19 epidemic, mobile learning has become one of the most significant learning approaches. The mobile learning resource is the basis of mobile learning; it may directly affect the effectiveness of mobile learning. However, the current learning resources cannot meet users' needs. This study aims to analyze the influencing factors of accepting open data as learning resources among users.

Based on the technology acceptance model (TAM) and the unified theory of acceptance and use of technology (UTAUT), this study proposed a comprehensive theoretical research model. Data were obtained from 398 postgraduates from several universities in central China. Confirmatory factor analysis was used to determine the reliability and validity of the measurement model. Data has been analyzed using SPSS and AMOS software.

The results suggested that perceived usefulness, performance expectancy, social influence and facilitating conditions have a positive influence on accepting open data as learning resources. Perceived ease of use was not found significant. Moreover, it was further shown in the study that behavioural intention significantly influenced the acceptance of open data as learning resources.

There is a lack of research on open data as learning resources in developing countries, especially in China. This study addresses the gap and helps us understand the acceptance of open data as learning resources in higher education. This study also pays attention to postgraduates' choice of learning resources, which has been little noticed before. Additionally, this study offers opportunities for further studies on the continuous usage of open data in higher education.

The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a formation mechanism of PAHs in fat during electric roasting, which is a method of non-direct-contact-flame heating.

The effects of animal fats and model fat on the formation of PAHs were valued on the basis of the ultra high-performance liquid chromatography data. The corresponding products of the FAME pyrolysis were detected by TG-FTIR. The proposal formation mechanism of PAHs was based on the summary of the literature.

Contrary to the International Agency for Research on Cancer, DF had higher risk with 280.53 ng/g of concentration after being roasted than the others animal fats of red meat in terms of PAHs formation. This research also ensured the importance of fat on PAHs formation, the concentration of PAHs in pure fats was higher after being electric roasted than that in meat patties and juice which made from corresponding animal fat. What is more, during pure animal fats and meat products being processed, less PAHs formed in the fat with lower extent of unsaturation and lower content of linolenate. In the same way, methyl linolenate demonstrated the significant increasement to PAHs formation compared to the other fatty acids. And, the number of carbon atom and the extent of unsaturation in fatty acid affects the formation of PAHs during roasting. The detection of alkene and alkane allows to propose a formation mechanism of PAHs during model fat being heated. Further study is required to elucidate the confirm moleculars during the formation of PAHs.

This work studied the effect of the carbon atom number and the unsaturation extent of fats and model fats on the formation of PAHs. This work also assure the important of alkene and alkane on the pyrolysis of model fats. This study also researched the formation and distribution of PAHs in pure fats and meat products after being heated.

This research examines the underlying psychological process of customers' impulsive buying on social media through the lens of customer inspiration. Drawing on the customer inspiration theory, it identifies the factors influencing customer inspiration on social media from three perspectives: source characteristics, platform characteristics and personal characteristics, which subsequently lead to impulsive buying. Since the conceptualization of source credibility includes three mostly reported components: attractiveness, expertise and trustworthiness, it further contrasts the effects of three dimensions of source credibility on customer inspiration.

A structural equation model of customers' impulsive buying on social media was developed through the lens of customer inspiration. An online survey with 625 participants was conducted to test the hypotheses, and the partial least squares (PLS3) method was used.

This research found that source credibility, social presence and customer innovativeness are antecedents of customer inspiration on social media, which positively influence the inspired-by state of the customers, which impacts the inspired-to state and further leads to impulsive buying. By comparing the three dimensions of source credibility, the authors found that attractiveness and expertise positively affect the inspired-by state, while trustworthiness has no significant effect.

This research establishes the link between impulsive buying and customer inspiration, which provides a new psychological perspective to understand impulsive buying. In addition, it investigates the source characteristics of customer inspiration by comparing the effect of three dimensions of source credibility on customer inspiration, which provides the first evidence for connecting customer inspiration and source credibility.

Wear failure happens frequently in rubber seal of high-speed rotating shaft because of the dry friction. Some traditional lubrication methods are not effective because of the restrictions on the relative high speed, temperature and others. This paper aims to present a new method of lubrication with gas film for the rotation shaft seal based on the contact design.

To obtain the generation condition of gas film and good effect of lubrication in the contact gap between the shaft and its seal, a series of micro-spiral grooves are designed on the contact surface of rubber seal so as to obtain a continuous dynamic pressure difference.

The result is that the distribution of the gas film in the micro-gap is continuous under the design of the spiral grooves and the contact with eccentricity because of the deformation of rubber seal, which is verified through the simulation calculation and experiment test. It is confirmed that the lubrication method with gas film through designing micro-spiral grooves on the contact surface is effective, and can achieve self-adaptive air lubrication for the high-speed shaft under the premise of the reliable sealing.

The method of gas film lubrication is realized through designing a microstructure of spiral grooves on the rubber surface to change the contact status, which can form a mechanism of adaptive lubrication to reduce the dry friction automatically in the contact gap. For the cross-scale difference between the rubber seal and gas film, a new modeling method is presented by building the mapping relation for the split blocks and repairing technique with integrated computer engineering and manufacturing, to reduce the possibility of nonconvergence and improve the efficiency and accuracy of calculation.

Through this research study, the authors found that digital thread has made significant progress in the life cycle management of the US Air Force. The authors hope that by reviewing similar studies in the aerospace field, the meaning of digital thread can be summarized and applied to a wider range of fields. In addition, theoretically, the definition of digital twin and digital thread are not unified. The authors hope that the comparison of digital thread and digital twin will better enable scholars to distinguish between the two concepts. Besides, the authors are also looking forward that more people will realize the significance of digital thread and carry out future research.

Complete research about digital thread and the relevant concept of the digital twin is conducted. First, by searching in Google Scholar with the keyword “digital thread”, the authors filter results and save literature with high relevance to digital thread. The authors also track these papers’ references for more paper of digital thread and digital twin. After removing the duplicate and low-relevance literature, 72 digital thread-related literature studies are saved and further analyzed from the perspective of time development, application field and research directions.

Digital thread application in industries other than the aviation manufacturing industry is still relatively few, and the research on the application of digital thread in real industrial scenarios is mainly at the stage of framework design and design-side decision optimization. In addition, the digital thread needs a new management mechanism and organizational structure to realize landing. The new management mechanism and the process can adapt to the whole life cycle management process based on the digital thread, manage the data security and data update, and promote the digital thread to play a better effect on the organizational management.

Based on a review of digital thread, future research directions and usage suggestions are given. The fault diagnosis of high-speed train bogie as an example shows the effectiveness of the method and also partially demonstrates the advantages and effects brought by the digital thread connecting the data models at various stages.

This paper first investigates and analyzes the theoretical connotation and research progress of digital thread and gives a complete definition of digital thread from the perspective of the combination of digital thread and digital twins. Next, the research process of digital thread is reviewed, and the application fields, research directions and achievements in recent years are summarized. Finally, taking the fault diagnosis of high-speed train bogie as an example partially demonstrates the advantages and effects brought by the digital thread connecting the data models at various stages.

The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.

The purpose of this paper is to provide evidence that firms that are more committed to internationalization, systematically differ from firms that are less committed to internationalization in their future intention to engage in foreign direct investment (FDI). The authors analyzed data from 42 large Brazilian multinational enterprises (MNEs) and found that results support previous research on the degree of satisfaction with prior internationalization efforts and future intent to internationalize, such that the relationship between the two is positive. Yet contrary to existing literature, the degree to which a firm was committed to internationalization has a negative influence on the positive relationship between satisfaction and intent.

All Brazilian firms that have entered foreign markets via FDI were surveyed to measure the firm’s: intent to internationalize; satisfaction with prior internationalization; and commitment to internationalization. Intent to internationalize is future based while both satisfaction and commitment reflect previous year’s activities. The potential response pool included publically traded companies listed on the Bovespa (São Paulo Stock Exchange) and private limited companies (Ltda.). The authors conducted a hierarchical moderated regression analysis to test the moderating effect of commitment to internationalization on the relationship between international satisfaction and intent to internationalize.

This study adds to the literature by examining how past international satisfaction and commitment affect the future intent to internationalize for large Brazilian MNEs. The results confirm that the degree of past satisfaction regarding a firm’s international business is positively related to the firm’s future intent to internationalize. However, the results diverge from past research in two important ways. First, contrary to the organizational behavior literature, past commitment to internationalization does not have a significant relationship with future intention to internationalize. Second, the results show the relationship between satisfaction and intent is weakened by a high degree of international commitment.

A limitation of this study is the small sample size. While it encompasses the vast majority of large MNEs in Brazil, the authors still do not have enough data points to test more hypotheses such as the effects of firm size, number of countries the firm is in, and age of the firm. Future studies should attempt to expand the work done here by examining these effects. Another limitation of this study is that it is based on solely one country; Brazil. Future studies should attempt to replicate these findings in other emerging market countries.

These results have three main managerial implications. First, international strategists analyzing the trajectory of a firm’s future intentions to internationalize should focus on how satisfied the firm has been with its past efforts. Second, managers should not assume that just because their firms have a large presence abroad that this will subsequently lead to future plans to internationalize. Finally, for emerging market MNEs in a period of the financial crises, committing more to internationalization may reduce the positive relationship between satisfaction and intention.

The purpose of this study is to add to the small but growing work on large MNEs from Brazil in order to better understand their internationalization strategies. While there are literally hundreds of articles investigating the individual-level relationship between satisfaction and the intent to do something, there are a dearth at the firm level (see Wood et al., 2011, as a notable exception). The authors therefore attempt to extend the literature on internationalization by discussing how satisfaction at the firm level affects a firm-level decision.