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The leakage problem caused by machining error, assembly error, wearing and thermal deformation has been the main factor hindering the development of scroll compressor. This paper aims to investigate the lubrication characteristics of radial clearance and further optimize the radial clearance, which can reduce the leakage in the tangential direction of the working chamber.

This paper establishes a model of radial clearance oil film lubrication in scroll compressor. And, the method to solve the Reynolds and energy equations is presented, as well as the dimensionless and discretization by finite element difference method. To verify the established model, performance experiment of scroll compressor for electric vehicle air conditioning system is also carried out.

Based on the presented model, the temperature field and distribution of the oil film in the radial clearance are analyzed. And the influence of the structural parameter on the radial clearance is further discussed. The optimum radial clearance could be achieved at β = 40°–42°, where the orbiting scroll is in the state of rotary balance. And, the simulation results coincide well with the experimental results.

This work provides an effective model to evaluate the lubrication characteristics of radial clearance in scroll compressor, which can provide guidance for the design of scroll compressor.

The purpose of this paper is to investigate the continued use behavior (CU) of link sharing tools based on uses and gratifications theory, the theory of planned behavior and expectation confirmation theory. It then builds a conceptual model that is empirically tested.

Data were collected from 343 students (undergraduates, masters, PhD students, and MBAs) from three Chinese universities via a two-phrase survey. The tools SPSS 18.0 and AMOS 18.0 were used to analyse the reliability, validity, model fits and SEM, respectively.

The results indicate that an individual’s CU of link sharing tools was determined by his or her continued use intention directly and subjective norm indirectly. Users’ satisfaction on link sharing tools was the main factor affecting the continuance intention. Individuals’ motivation needs such as cognitive needs, personal integrative needs, and social integrative needs were found to be the significant predictors of his or her satisfaction. Besides, people with high privacy concern tended to have less satisfaction with link sharing tools.

This study explores users’ CU of link sharing tools in social media for the first time. The theoretical model developed shows the predictors behind people’s CU.

The purpose of this paper is to test the relationship between environmental regulations and green total factor productivity (GTFP) of China's logistics industry. The high-factor input, high-energy consumption, and high-pollution emissions model of the logistics industry developed within China faces challenges from severe resource and environmental constraints. It is generally believed that environmental regulations effectively restrain pollution emissions and help protect the environment.

The authors employ the undesirable slack-based Malmquist Luenberger model to calculate the GTFP across the provincial logistics industry and use the mediation effect model and threshold effect model to explore the effects and mechanics of environmental transmission regulations on the GTFP.

The main results show significant regional differences in the GTFP of logistics industry across China. In the transmission path of the impact of environmental regulations on the GTFP, regional innovation capabilities have mediation effects. Regional innovation capacities have a masking effect on the transmission path of environmental regulations on accumulated technical efficiency changes (AEC) and accumulated technical changes (ATC). The threshold effect test results show a dual-threshold effect between environmental regulations and the GTFP, with environmental regulations as threshold variable. Furthermore, the impact of regional innovation capability on the GTFP has a dual-threshold effect, with environmental regulation as threshold variable.

First, it is advisable to plan the environmental regulation policy system thoroughly and add supporting measures to ensure the efficiency and smooth implementation of the nation's environmental policies. Second, it is important to further understand the critical role of innovation capability in improving the GTFP. Third, there is an urgent need to standardize the operating behavior and market order of the leading players in the logistics market and to improve the operational efficiency of logistics enterprises.

So far, a systematical study researched on effect of environmental regulation on the GTFP in logistics industry was not published. This study can provide experience for the high-quality development of the logistics industry.

This study aims to offer a comprehensive exploration of the potential and challenges associated with sensor fusion-based virtual reality (VR) applications in the context of enhanced physical training. The main objective is to identify key advancements in sensor fusion technology, evaluate its application in VR systems and understand its impact on physical training.

The research initiates by providing context to the physical training environment in today’s technology-driven world, followed by an in-depth overview of VR. This overview includes a concise discussion on the advancements in sensor fusion technology and its application in VR systems for physical training. A systematic review of literature then follows, examining VR’s application in various facets of physical training: from exercise, skill development and technique enhancement to injury prevention, rehabilitation and psychological preparation.

Sensor fusion-based VR presents tangible advantages in the sphere of physical training, offering immersive experiences that could redefine traditional training methodologies. While the advantages are evident in domains such as exercise optimization, skill acquisition and mental preparation, challenges persist. The current research suggests there is a need for further studies to address these limitations to fully harness VR’s potential in physical training.

The integration of sensor fusion technology with VR in the domain of physical training remains a rapidly evolving field. Highlighting the advancements and challenges, this review makes a significant contribution by addressing gaps in knowledge and offering directions for future research.

Recognizing every worker's working status instead of only describing the existing construction activities in static images or videos as most computer vision-based approaches do; identifying workers and their activities simultaneously; establishing a connection between workers and their behaviors.

Taking a reinforcement processing area as a research case, a new method for recognizing each different worker's activity through the position relationship of objects detected by Faster R-CNN is proposed. Firstly, based on four workers and four kinds of high-frequency activities, a Faster R-CNN model is trained. Then, by inputting the video into the model, with the coordinate of the boxes at each moment, the status of each worker can be judged.

The Faster R-CNN detector shows a satisfying performance with an mAP of 0.9654; with the detected boxes, a connection between the workers and activities is established; Through this connection, the average accuracy of activity recognition reached 0.92; with the proposed method, the labor consumption of each worker can be viewed more intuitively on the visualization graphics.

With this proposed method, the visualization graphics generated will help managers to evaluate the labor consumption of each worker more intuitively. Furthermore, human resources can be allocated more efficiently according to the information obtained. It is especially suitable for some small construction scenarios, in which the recognition model can work for a long time after it is established. This is potentially beneficial for the healthy operation of the entire project, and can also have a positive indirect impact on structural health and safety.

The study aims to examine the effect of inclusions and inherent microstructure on fatigue behavior of 34Cr2Ni2Mo steel.

Fatigue behavior of 34Cr2Ni2Mo steel was investigated for up to 1E10 cycles.

Results showed that both inclusion and inherent microstructure have an influence on the crack initiation mechanism. Fatigue cracks mostly initiated from inclusions, whereas substrate-induced crack initiations were also observed. Fatigue life of inclusion-induced failures is mostly determined by the location of inclusions rather than the loading stress. The inherent microstructure seems to tolerate inclusions at a lower stress level in very high-cycle regime owing to the absence of internal inclusion-induced failure. For the substrate-induced crack initiations, high-density dislocations are found to be accumulated around the carbide particle-matrix interface, which may be the cause of crack initiation in the inherent structure due to strain localization.

The effect of inclusions and inherent microstructure on fatigue behavior of 34Cr2Ni2Mo steel up to 1E10 cycles.

Highlights

• Fatigue failure occurs even at a lifetime of 5.76E9 cycles.

• Surface inclusion induced premature failures.

• Inherent microstructure tolerates inclusions at lower stress level.

• Internal carbides promote substrate-induced crack initiations.

Fatigue failure occurs even at a lifetime of 5.76E9 cycles.

Surface inclusion induced premature failures.

Inherent microstructure tolerates inclusions at lower stress level.

Internal carbides promote substrate-induced crack initiations.

The purpose of this paper is to start with the background of the construction of the M-score model, find the variables that can represent the fraud characteristics of Chinese companies, and use the data of Chinese A-share listed companies to modify the M-score model.

In this paper, the fraud behavior of Chinese enterprises that M-score cannot detect is summarized as the basis of adding variables. Then, based on the data of Chinese listed companies, a modified M-score model including nine variables is constructed by the logistic regression method based on Wald.

Based on the original 8 variables of M-score, this paper adds 10 new variables that can represent the fraud characteristics of Chinese listed companies, and finally, constructs a modified M-score model with 9 variables. Results indicated that indexes such as gross profit margin, fixed assets depreciation rate, equity concentration and audit opinion can characterize the financial fraud of Chinese listed companies.

The modified M-score model based on the characteristics of Chinese enterprises’ fraud is more suitable for Chinese market, which can help investors avoid fraud risks, protect their own rights and interests and reduce losses.

Starting from the background of the model, this paper looks for variables that can characterize the characteristics of fraud in Chinese listed companies. Then, subdivides the research samples into specific fiscal years in which fraud occurs, so that the modified M-score model can be more suitable for the Chinese market.

The purpose of this paper is to study the influence of friction coefficient of materials with different elastic modulus on the variation of velocity and load under water lubrication and oil lubrication conditions.

Low-viscosity lubricating oil and water were used as lubricants to test the friction performance of the ball-disc contact friction pair in the lubrication state on the universal micro-tribometer multi-functional friction and wear test system.

In the same speed range, the lubrication states from soft to rigid materials are not necessarily similar to each other. Generally, the material with low elastic modulus is suitable in low-viscosity lubricant environments, while the material with high elastic modulus has relatively smaller friction coefficients in oil-lubricated environments compared with water lubrication. However, the coefficients of polyethylene, polytetrafluoroethylen and polyoxymethylene are exceeded by rubber’s coefficients under water lubrication in the same experiment environments, and their lubrication states are not affected by lubricants. The friction coefficient of the friction pair decreases with the increase of loads; however, it does not apply to all materials. The friction coefficients of materials with smaller elastic modulus such as rubber under high loads are rather large. Therefore, the elastic modulus of the material under high loads is a factor to be considered.

The Stribeck curves study of the ball-disk contact friction pair comprising soft and rigid materials, whose elastic modulus is from hundreds of GPa to a few of MPa, was carried out. The influence of different speeds, loads and lubricants on the friction coefficient of the friction pair was revealed, which provided a research basis for the selection and matching of friction pair materials.

With the accelerating process of urbanization, the greening areas in high density cities are becoming less and less, and the aerial greening provides a possible way for the update of the urban building headspace greening. Based on this, the application of aerial greening in the urban headspace was studied. Starting from the plant, water, landscape sketch, pavement and other construction elements, the ecological art planning and design of the urban building headspace was studied. Then, the transformation of an old factory was studied, and the rain-flood gardens and infiltration floors linked to biological corridors were introduced in the high flood risk areas. In the building headspace, a rainwater harvesting system and an air garden were designed, and the ecological planning of aerial walkway was carried out to the front abandoned viaduct. The practice proves that the introduction of ecological science and technology and art culture in the urban headspace plays an important role in purifying urban air and increasing urban greening.

Confucian nurturing doctrine of xin (heart‐mind) comprehensively illustrates the importance of emerging state of feelings, which are the antecedents of organizational and individual behaviors. This introductory paper seeks to provide meaningful references for the management education and research trends like organizational justice and emotional intelligence.

Based on Confucian nurturing doctrine of xin (heart‐mind), this paper analyzes: the connotation of xin, qing (emotions/feelings) as the manifestation of xing (nature) by xin, and the cultivation of xin. Accordingly, the authors propose the holistic man model based on emotions.

The holistic man model based on emotions contains natural, social, moral, and transcendental dimensions. Self‐cultivation is significant for management practices and education.

As a conceptual essay, the statements in the paper need further argument and exploration.

A referential hypothetical model of human nature based on Confucian nurturing doctrine of xin can make people have transcendent aspiration in their daily life and focus on the unity of individuals' natural feelings and moral cultivation. In this case, people can live an integrated, meaningful and healthy life based on their emerging state of emotions, which are the antecedents of the transactional, instrumental, and procedural regulations.

This paper contributes to the notions of the holistic man based on emotions and emerging state of emotions by referring to Confucian nurturing doctrine of xin (heart‐mind).