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The purpose of this paper is to summarize the status and characteristics of rail technology of high-speed railway in China, and point out the development direction of rail technology of high-speed railway.

This study reviews the evolution of high-speed rail standards in China, comparing their chemical composition, mechanical attributes and geometric specifications with EN standards. It delves into the status of rail production technology, shifts in key performance indicators and the quality characteristics of rails. The analysis further examines the interplay between wheels and rails, the implementation of grinding technology and the techniques for inspecting rail service conditions. It encapsulates the salient features of rail operation and maintenance within the high-speed railway ecosystem. The paper concludes with an insightful prognosis of high-speed railway technology development in China.

The rail standards of high-speed railway in China are scientific and advanced, highly operational and in line with international standards. The quality and performance of rail in China have reached the world’s advanced level. The 60N profile guarantees the operation quality of wheel–rail interaction effectively. The rail grinding technology system scientifically guarantees the long-term good service performance of the rail. The rail service state detection technology is scientific and efficient. The rail technology will take “more intelligent” and “higher speed” as the development direction to meet the future needs of high-speed railway in China.

The development direction of rail technology for high-speed railway in China is defined, which will promote the continuous innovation and breakthrough of rail technology.

This paper aims to propose a real-time evolutionary multi-objective semi-analytical inverse kinematics (IK) algorithm (EMSA-IK) for solving the multi-objective IK of redundant manipulators.

Within EMSA-IK, the parameterization method is applied to reduce the number of optimization variables of the evolutionary algorithm and calculate semi-analytical solutions that meet high target pose accuracy. The original evolutionary algorithm is improved with the proposed adaptive search sub-space strategy so that the improved evolutionary algorithm can be used to efficiently perform global search within the parametric joint space to obtain the global optimal parametric joint angles that satisfy multi-objective constraints.

Ablation experiments show the effectiveness of the improved strategy used for evolutionary algorithms. Comparative experiments on different manipulators demonstrate the advantages of EMSA-IK in terms of generalizability and balancing multiple objectives, for example, motion continuity, joint limits and obstacle avoidance. Real-world experiments further validate the effectiveness of the proposed algorithm for real-time application.

The semi-analytical IK solution that simultaneously satisfies high target pose accuracy and multi-objective constraints can be obtained in real time. Compared to existing semi-analytical IK algorithms, the proposed algorithm achieves obstacle avoidance for the first time. The proposed algorithm demonstrates superior generalizability, applicable to not only redundant manipulators with revolute joints but also those with prismatic joints.

The purpose of the paper is to propose an efficient, simple and concise unified robot calibration method that simultaneously considers errors in hand-eye parameters, kinematic parameters and tool center point (TCP) position.

This paper proposes a unified robot calibration method. First, the initial hand-eye matrix and TCP position are computed without considering kinematic parameter errors. Second, the nominal TCP positions in the laser tracker coordinate system {S} are computed. The actual TCP positions in {S} are directly measured. Third, a unified parameter error calibration model is established, and the sequential quadratic programming algorithm is used for error identification. Finally, the identified errors are used for direct error compensation.

Simulation results prove that the proposed scheme can accurately calibrate the hand-eye parameters, kinematic parameters and TCP position simultaneously. Experimental results reveal that the maximum value of the absolute positioning errors is reduced from 5.4725 mm to 0.4095 mm (reduced by 92.52%). Thus, the proposed approach meets the accuracy requirements of most robotic applications.

The main contributions of this paper are: (1) this scheme is efficient. The method can achieve fully automatic calibration by incorporating Kronecker products for the initial hand-eye matrix and TCP position computation. Thereby significantly improving the calibration efficiency and liberating the labor force. (2) This scheme is simple and concise. The hand-eye parameters, kinematic parameters and TCP position errors are modeled in a unified framework. Furthermore, the related redundant parameters are deleted.

This paper describes a new method designed for a quartz tuning‐fork temperature sensor. This sensor is designed with a new cut ZYtw(115°/15°) and it is shown that this worked best in flexural vibration mode. The way for raising signal to noise ratio and reducing equivalent resistor of the sensor were analyzed in theory. A manufacturing method has been determined to form and adjust the precise frequency, which could improve sensitivity and reduce non‐linearity.

Purpose: This study investigates how couple similarity in various aspects affects their life satisfaction and how these impacts vary across educational groups among the young married couples in Shanghai.

Methodology: This study employs the pooled data from three waves of the Fudan Yangtze River Delta Social Transformation Survey which sampled Shanghai youths born between 1980 and 1989, the first single-child generation. Couple similarity is evaluated through the comparison in age, hukou status, education, and income quartile between the husband and wife. Ordered logistic regression model is applied to assess the impacts of couple similarity on life satisfaction.

Findings: Marriage hypergamy in age, education, and income barely have any impacts on couples’ life satisfaction, while hukou comparison, as an important indication of social stratification in Shanghai, is strongly associated with life satisfaction. The couple in which husband holds the urban hukou and wife rural hukou as well as the couple in which both partners hold the urban hukou are significantly happier than those in which both partners hold the rural hukou. Such a positive impact is partially explained by the higher husband’s decision-making power in male-advantaged families. Moreover, husband’s urban hukou status is especially important for those without college education, but not for those with college education.

Values: This chapter highlights the importance of hukou hypergamy in life satisfaction for married couples, in particular, lower-educated couples in Shanghai. These findings reveal an implicit but persistent preference for male-dominated family model, where husbands retain a higher decision-making power that, in turn, promotes life satisfaction for both partners.

The shape of a product plays a crucial role in shaping consumer behavior. Despite the voluminous research on factors influencing consumers’ shape preferences, there remains a limited understanding of how the busy mindset, a mentality increasingly emphasized by marketing campaigns, works. This study aims to fill this gap by exploring the relationship between a busy mindset and the preference for angular-shaped versus circular-shaped products and brand logos.

This research consists of seven experimental studies using various shape stimuli, distinct manipulations of busy mindset, different assessments of shape preference and samples drawn from multiple countries.

The findings reveal that a busy mindset leads to a preference for angular shapes over circular ones by amplifying the need for uniqueness. In addition, these effects are attenuated when products are scarce.

This research represents one of the pioneering efforts to study the role of a busy mindset on consumers’ aesthetic preferences. Beyond yielding insights for practitioners into visual marketing, this research contributes to the theories on the busy mindset and shape preference.

Limited use of Internet of Things (IoT) technology on construction sites has restricted its value in the construction industry. To propel its widespread application, this paper explores the influencing factors and action paths of construction companies' IoT technology adoption behavior.

First, literature research, technology adoption theories, and semi-structured expert interviews were employed to build the adoption model. Second, a questionnaire survey was conducted among Chinese construction contractors to collect empirical data. Third, the structural equation model method and regression analysis were used to test the adoption model. Finally, the findings were further validated with interviews, case studies, and field observations.

External environmental pressure (EEP), perceived benefit (PB), top management support (TMS), company resource readiness (CRR), adoption intention (AI), and perceived compatibility (PCA) have a direct positive impact on adoption behavior (AB). In contrast, perceived cost (PC) and perceived complexity (PCL) exert a direct negative impact on AB. The EEP, PB, and PC are critical factors affecting AB, whereas AI is strongly affected by CRR and TMS. Besides, AI plays a part mediating role in the relationship between seven factors and AB. Company size and nature positively moderate AI's positive effect on AB.

This paper contributes to the knowledge of IoT technology adoption behavior in the construction sector by applying the technology adoption theories. Exploring the implementation barriers and drivers of IoT technology in construction sites from the perspective of organizational technology adoption behavior and introducing moderating variables to explain adoption behavior are innovations of this paper. The findings can help professionals better understand the IoT technology adoption barriers and enhance construction companies' adoption awareness, demand, and ability. This work also provides a reference for understanding the impact mechanism of the adoption behavior of other innovative technologies in construction.

This study aims to investigate the effect of the virtual spokesperson type on the consumers' preference for new products. To meet the consumer needs of Generation Z, virtual spokespeople have become new assistants in brand marketing. However, how virtual spokespersons drive consumer preference for new products is minimally understood.

This research conducts three experiments to investigate the influence of virtual spokesperson type on consumers' preference for new products.

The research shows that, for radically new products, competent virtual spokespersons improve consumers' perception of self-efficacy and thus consumers' preference; for incrementally new products, warm virtual spokespersons improve consumers' perception of social connection and thus consumers' willingness to buy.

This study broadens research on brand spokespersons and virtual spokespersons. This research also enriches and expands research on the consideration of new product types in brand spokespersons.

This study aims to examine how loneliness, romantic relationship status (single/non-single) and romantic attachment factors (sociosexual orientation index (SOI), satisfaction with current relationship) interactively affect conspicuous consumption.

Five quasi-experimental studies were conducted with different measures of conspicuous consumption across a variety of samples (N = 1189).

Study 1 shows that loneliness increased singles’ but not non-singles’ conspicuous consumption. Study 2A further shows the mediating role of the mating motive amongst singles. Study 2B compared conspicuous and inconspicuous consumption and showed no interaction effect between loneliness and romantic relationship status in the domain of inconspicuous consumption. Studies 3 and 4 tested whether the effects of loneliness on non-singles’ conspicuous consumption were moderated by SOI and satisfaction with current relationship, respectively. Specifically, lonely non-singles with high SOI or low satisfaction with current relationship sought conspicuous consumption, but those with low SOI or high satisfaction with the current relationship avoided conspicuous consumption.

This study did not specifically consider different roots of loneliness (lack of romantic love, friendship or family attachment) between singles and non-singles, which future research should explore.

The findings have implications for both marketers and policymakers regarding marketing campaigns for conspicuous products, support programmes satisfying the specific social attachment needs of different lonely people, etc.

This study identifies a specific social attachment desire of the lonely, namely, romantic motive, by which loneliness influences singles’ and non-singles’ conspicuous consumption in different ways. The findings suggest the value of distinguishing types of loneliness.