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The analysis carried out in this study can provide guidance for manufacturers and researchers to design a piston for the development of engines.

Running conditions for pistons have become very severe because of the high combustion pressure and increase in piston temperature in the past 10 years. The precision of the model has a great effect on the power transmission, vibration noise emission. In this paper, the model was established with lubrication and dynamic governing equations, which were solved using finite element method coupled with Runge–Kutta method. A piston of an inline six-cylinder engine was studied, and some structural parameters were used to investigate its effect on the friction loss with lubrication and dynamic motion theory.

Based on the analyses, the effect of the friction load at the oil groove and thermal deformation of piston skirt were added to the model, and some useful information about the friction loss and dynamic characteristics were compared.

All the results will provide guidance for the development of the piston and reduction in the friction loss and wear.

This paper aims to give the guidance for the design of the bearing.

The finite element method, the multi-body dynamics method, the finite difference method and the tribology are combined to analyze the lubrication.

The performance parameters of crankshaft-bearing system such as the misalignment, the oil filling ratio and the oil groove are also investigated. Misalignment causes the pressure to incline on one side and the pressure increases obviously. Filling ratio has great relationship with pressure distribution; the factors influencing the filling ratio are also analyzed. Different oil groove models are investigated, as it can provide the theory for oil groove design, and three factors above are always combined to influence the lubrication characteristics.

The optimization of bearing system is conducted by orthogonal test and neural network, unlike the linear optimization theory. Neural network uses the nonlinear theory to optimize crankshaft-bearing system.

Piston ring dynamic problem plays an important role in the lubricant characteristics of a reciprocating engine, which lead to engine wear and the increased consumption of lubricating oil. A cavitation analysis of the piston ring lubrication with two-dimensional Reynolds equation has rarely been reported owing to the complex working condition. The purpose of this study is to establish a precise model that can provide guidance for the design of the piston ring.

In this paper, a cavitation model and its effect on the piston ring lubrication was studied in a simulation program based on the mass-conserving theory which is solved by means of the Newton–Raphson method. In this study, some models such as mixed lubrication, asperity contact, blow-by/blow-back flow and cavitation have been coupled with the lubrication model.

The established model has been compared with the traditional model that deals with cavitation by using the Reynolds boundary condition algorithm. The cavitation zone, pressure distribution and density distribution between the piston ring and the cylinder have also been predicted. Studies of the changing trend for the pressure distribution and the cavitation zone at few typical crank angles have been listed to illustrate the cavitation changing rule. The analysis of the results indicates that the developed simulation model can adequately illustrate the lubrication problem of the piston ring system. All the analyses will provide guidance for the oil film rupture and the reformation process.

A two-dimensional cavitation model based on the mass-conserving theory has been built. The cavitation-forming and -developing process for the piston ring–liner lubrication has been studied. Non-cavitation occurs in the vicinity of top dead center and bottom dead center. The non-cavitation period will be longer in the vicinity of 360° of crank angle. The density distribution in the cavitation zone can be obtained.

The purpose of this paper is to improve the environment and save energy, friction reduction, lower oil consumption and emissions demand that are the chief objectives of the automotive industry. The piston system is the largest frictional loss source, which accounts for about 40 per cent of the total frictional loss in engine. In this paper, the reciprocating tribometer, which is updated, was used to evaluate the friction and wear performances.

An alternate method is introduced to investigate the effect of reciprocating speed, normal load, oil pump speed and ring sample and oil temperature on friction coefficient with the ring/liner of a typical inline diesel engine. The orthogonal experiment is designed to identify the factors that dominate wear behavior. To understand the correlations between friction coefficients and wear well, different friction coefficient results were compared and explained by oil film build-up and asperity contact theory, such as the friction coefficient over a long period and averaged the friction coefficient over one revolution.

The friction coefficient changes little but fluctuates with a small amplitude in the stable stage. The sudden change of frequency, load and stroke will lead to the oil film rupture. The identification for the factors that dominates the wear loss is ranged as F (ring sample) > , E (oil sample) > , B (stroke) > , D (temperature) > , A (load) > , G (liner) > and C (frequency).

This paper develops and verifies a methodology capable of mimicking the real engine behavior at boundary and mixed lubrication regimes which can minimize frictional losses, wear, reduce much work for the experiment and reduce the cost. The originality of the work is well qualified, as very few papers on a similar analysis have been published, such as: The friction coefficient values fluctuating in the whole stage may be caused by the vibration of the system; suddenly, boundary alternation may help the oil film to form the lubrication; and weight loss mainly comes from the contribution of the friction coefficient value fluctuation. The paper also found that the statistics can gain more information from less experiment time based on a design of experiment.

This study aims to investigate the mediating role of collective identity in the relations among transformational leadership, procedural justice and employee organizational commitment.

An empirical survey was conducted in 43 hotels in mainland China with 585 valid responses. In addition to descriptive statistics and the test of the presence of common method bias, a confirmatory factor analysis was conducted to test the validities and reliabilities of the variables; structural equation modeling and hierarchical regression analyses were conducted to test causal relations and the mediating effects of collective identity.

Results show that transformational leadership and procedural justice are good predictors of employee collective identity and organizational commitment. In addition to a strong impact on employee commitment, collective identity partially mediates the effects of transformational leadership and procedural justice on employee commitment.

This study is restricted to China’s hotel supervisors; therefore, caution should be taken when applying the findings to other sectors, regions and higher levels of leaders.

Findings of this study offer managerial insights for hotel supervisors to exercise transformational leadership and procedural justice to improve employee collective identity, which drives organizational commitment.

As an important concept, studies on the role of self-identity are limited in management and the field of leadership. This study tested the role of collective identity in leadership and organizational commitment in the context of Chinese culture, highlighting its theoretical and practical implications.

With strategy-as-practice theory the authors explore successful business-owning families hand-over of roles to the next generation. The authors argue for the usefulness of strategy-as-practice theory in exploring the complexity and plurality of best practices in intergenerational hand-over. The paper aims to discuss these issues.

A cross-cultural in-depth case study with best practice cases from China, Germany, Sweden, England, Tanzania, Israel and the USA, based on in-depth interviews of family members and non-family employees.

The authors identified three different succession patterns: a “monolithic practice,” a distributed leadership hand-over, and active ownership with a non-family managing director/CEO. Two other types of hand-over practices were categorized as incubator patterns that formed a part of, or replaced, what we traditionally see as a hand-over of roles. Families would switch between these practices.

Surprisingly, a monolithic succession practice (a one-company-one-leadership role) was rarely used. Quantitative and qualitative research should consider, as should advisors to family owners and family businesses, the plurality of succession practices. Education should explore a variation of succession and how the dynamic of gender influences the process.

Giving practitioners, such as research and practitioner, an overview of strategic options so as to explore these in a client or research case.

Adding the notions that the family is an incubator for new entrepreneurship makes it possible to show how not only sector or public policy generate new ventures. That family as source of entrepreneurship has been well established in the field but it mainstream policy thinking the family is not seen as such a source.

The paper offers an integrative model of the complexity of hand-over practices of ownership and leadership roles. It shows how these practices are fundamental for understanding how a family’s ownership and their leadership of businesses and new entrepreneurship develops.

The purpose of this paper is to determine how customers from different market segments assess the quality of freight forwarding services, depending on the structure of services, as well as the mutual relation between the freight forwarder and the customers.

The research is based on the SERVQUAL model and surveys. The methodology for measuring the quality of logistics services in freight forwarding companies is developed. On the basis of the proposed methodology, the empirical research was conducted. The study includes 120 logistics professionals dealing with import and export trade flows who thereby use the services of freight companies. The verification of the SERVQUAL instrument, results and hypotheses are conducted using the factor analysis and ANOVA.

The results show that logistics service quality (LSQ) of freight forwarding companies in Serbia is not at a satisfactory level. Different market segments evaluate the level of quality of service in a different way. Also, customer exceptions and the level of quality depend on the structure of services, as well as the mutual relation between the freight forwarder and the customers.

Empirical research and the results are limited to the Serbian market, and only one measurement tool.

The procedure and results of the research have practical applications and set the basis for the improvement of forwarding and logistics services.

This is one of the first papers dealing with the LSQ of freight forwarding companies in Serbia. Generally, the developed approach can be successfully applied on other markets, which adds value to this paper. New research hypotheses are developed and tested. In that manner, this paper makes contribution in measuring and improving the LSQ.