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The frictional behavior of a Mo alloy‐coated piston ring sliding against cast iron cylinder bore was recorded as a function of temperature using a reciprocating tribotester and a fully formulated synthetic engine oil, with and without a friction modifier. It was observed that, as temperature increased in a stepwise mode, friction coefficients in the presence of MoDTC exhibited two local minimal values. Only one minimal friction coefficient value at 340–355 °C (μ = 0.065) was observed in the absence of MoDTC. Chemical characterization of worn tracks of the cylinder bore using reflected FTIR spectroscopy, Raman spectroscopy and ESCA, indicated that both the base stock and the tribological additives, ZDTP and MoDTC, experienced tribochemical reactions yielding MoO₃, MoS₂ and carbonaceous species as temperature ramped up stepwise. MoO₃ and MoS₂ reaction film formation are partially responsible for the local minimal friction coefficient found at the lower temperature and the ratio of the ordered carbon species accounts partially for the other local minimal friction coefficient found at the higher temperature.

Improved fuel economy, lower emission and longer durability are the major developing trends of engine oils. Aims to describe further research on the friction coefficient of engine oils.

The lubricating durability D was defined based on definition of three characteristic points P_d, P_S, P_i and three key time lengths T_d, T_s, T_i. Two kinds of engine oils, respectively, belonging to GF‐2 and GF‐3 categories, were selected as samples to compare their lubricating durability.

Test results indicate the GF‐3 oil has much better lubricating durability than GF‐2 oil. With investigation of the topography and chemical composition changes of wear tracks along with the tribotests' time extending, the meanings of three characteristic points were discussed. Analysis indicates much better tribofilm, formed by the synergistic effect of Ca‐containing detergent with MoDTC/ZDTP in GF‐3 oil, is the major factor resulting in GF‐3 oil's longer lubricating durability.

Provides further research on lubricating durability, which is important for engine oil change and maintenance, as well as decreased cost and pollution to the environment, and improved energy conservation.

To propose a new investment-income valuation model by real options approach (ROA) for old community renewal (OCR) projects, which could help the government attract private capital's participation.

The new model is proposed by identifying the types of options private capital has in the OCR project, selecting the option model most suitable for private capital investment decisions, improving the valuation model through the triangular fuzzy numbers to take into account the uncertainty and flexibility, and demonstrating the feasibility of the calculation model through an actual OCR project case.

The new model can valuate OCR projects more accurately based on considering uncertainty and flexibility, compared with conventional methods that often underestimate the value of OCR projects.

The investment-income of OCR projects shall be re-valuated from the lens of real options, which could help reveal more real benefits beyond the capital growth of OCR projects, enable the government to attract private capital's investment in OCR, and alleviate government fiscal pressure.

The proposed OCR-oriented investment-income valuation model systematically analyzes the applicability of real option value (ROV) to OCR projects, innovatively integrates the ROV and the net present value (NPV) as expanded net present value (ENPV), and accurately evaluate real benefits in comparison with existing models. Furthermore, the newly proposed model holds the potential to be transferred to various social welfare projects as a tool to attract private capital's participation.

The study aims to pioneer an innovative approach for the evaluation of government portal websites (GPWs) by introducing an eye-tracking-based method. The research meticulously pinpoints and analyses the distinct usability issues and challenges that users encounter while navigating and interacting with GPWs.

This study devises an eye-tracking-based GPW usability evaluation approach, which focuses on the major functions (i.e. government information disclosure, government services and interactive responses) of GPWs. An Entropy Weighted Technique for Order Preference by Similarity to an Ideal Solution (EW-TOPSIS) method is employed to process eye-tracking indicator results for deriving GPW usability results.

The proposed approach is demonstrated to assess the usability of 12 GPWs in pilot smart cities in China, and it is found that most GPWs have lower-than-average usability. GPWs with low usability require more cognitive load that exhibit increased fixation and saccade. The comparisons among the GPW usability results from (1) the eye-tracking experiment, (2) questionnaire surveys and (3) the ready-made performance evaluation report validate the effectiveness of eye-tracking-based GPW usability evaluation.

The work contributes to shifting the GPW usability evaluation approach from a subjective judgment paradigm to an objective paradigm, as well as provides implications for enhancing GPW usability, including improving search function, reducing website complexity and prioritizing user needs.

The core of the successful implementation of the integrated project delivery (IPD) mode is to establish a high-quality relationship of cooperation, trust and sharing among participants. This paper proposes recommendations to improve the relationship quality of participants from the owner's perspective. The results provide the theoretical basis and practical guidance for the popularization and application of the IPD mode.

This paper analyzes the dynamic relationship among participants in IPD mode based on supply chain theory and similarity theory. A tripartite game model of the owner, designer and the contractor is constructed to obtain the evolutionary equilibrium strategies under different parameter constraints. Then, numerical simulations under various scenarios are conducted to explore the dynamic evolution and the influencing factors of the relationship quality among the participant in the IPD mode.

The results show that (1) the relationship quality under certain conditions gradually improves as the project progresses until stable and high-quality cooperation is formed and (2) the owner's positive supervision cost, the distribution coefficient of incentive and punishment of participants and the scale of incentive pool are important factors influencing the relationship quality.

This study incorporates the following three innovations. First, analyzing the relationship quality among the participants of IPD mode based on supply chain theory. Second, the evolutionary game theory is applied to the relationship quality analysis. Third, conclusion innovation. The authors conclude that the relationship quality may progress, decrease or cycle with the progress of the project and targeted recommendations are presented based on the results.

In the architecture, engineering and construction (AEC) industry, technology developers have difficulties in fully understanding user needs due to the high domain knowledge threshold and the lack of effective and efficient methods to minimise information asymmetry between technology developers and AEC users. The paper aims to discuss this issue.

A synthetic approach combining domain knowledge and text mining techniques is proposed to help capture user needs, which is demonstrated using building information modelling (BIM) apps as a case. The synthetic approach includes the: collection and cleansing of BIM apps’ attribute data and users’ comments; incorporation of domain knowledge into the collected comments; performance of a sentiment analysis to distinguish positive and negative comments; exploration of the relationships between user sentiments and BIM apps’ attributes to unveil user preferences; and establishment of a topic model to identify problems frequently raised by users.

The results show that those BIM app categories with high user interest but low sentiments or supplies, such as “reality capture”, “interoperability” and “structural simulation and analysis”, should deserve greater efforts and attention from developers. BIM apps with continual updates and of small size are more preferred by users. Problems related to the “support for new Revit”, “import & export” and “external linkage” are most frequently complained by users.

The main contributions of this work include: the innovative application of text mining techniques to identify user needs to drive BIM apps development; and the development of a synthetic approach to orchestrating domain knowledge, text mining techniques (i.e. sentiment analysis and topic modelling) and statistical methods in order to help extract user needs for promoting the success of emerging technologies in the AEC industry.

The existing mashup literature paid little attention to the actual adoption and diffusion of mashups in an organizational context. As more and more organizations are engaged in mashup initiatives, more research efforts focussing on the mashup use and adoption issues from the organizational perspective are needed to ensure that organizations can receive the maximum benefits from their mashup initiatives. Two studies are conducted to increase the understanding of the use and adoption issues with social media mashups. The paper aims at discussing these issues.

The paper first used a text mining approach to analyze relevant posts on blogs and messages in a major online mashup forum in order to understand the current status of social media mashup as well as representative themes and issues with social media mashups in general. Subsequently, the paper reviewed a number of social media mashup sites created by higher education institutions (HEIs) in the USA.

The paper identified some representative themes and issues with social media mashups in general. The paper also identified the approaches that were used to design the interface of social media mashup sites by HEIs. Based on the two studies, this paper provides recommendations and insights to guide social media mashup development and adoption in an organizational context.

This is the first article to discuss the use and adoption of social media mashups in organizational environments. This paper can be used as a starting point to motivate other researchers to further explore the diffusion of social media mashups in different industries. This paper also helps organizations improve their social media mashup initiatives.

Although internet plus government platforms (IPGPs) are being increasingly used by citizens around the world, questions emerge regarding the public adoption, utilization and use of IPGPs. This study aims to explore the determinants of citizens’ differentiated IPGPs usage behaviors.

An analytical framework has been built upon the rational choice theory and the cultural dimension theory. The present study draws on a survey of 866 citizens from Guangzhou, Wuhan and Chengdu.

The empirical findings suggest that the perceived functional benefits and personalization features both significantly affect citizens’ informational, service and participatory uses of IPGPs, to varying degrees. Furthermore, long-term orientation plays a moderating role in the relationship between perceived functional benefits and the service use of IPGPs.

The findings demonstrate that the public’s rational choice of a new digitalized service channel depends on to what extent and to what degree the absolute and relative benefits they consider important compare to other possible channels. Users also consider how the new service channel satisfies their personalized demands of digitalized services. Also, users’ long-term orientation can affect their rational choices by adjusting the perceived functional benefits of the channel when that channel is used for service transactions.

The purpose of the current article was to propose the strengths-based human resource (HR) system construct as well as develop and validate the perceived strengths-based HR system scale by using three independent studies.

Study 1 mainly adopted exploratory factor analysis to test whether fifteen items proposed by the authors can represent the perceived strengths-based HR system construct. The aim of Study 2 was to examine the discriminant validity and criteria validity of the fifteen-item perceived strengths-based HR system scale and reliability of this scale. By structural equation modeling analysis, Study 3 primarily tested the incremental predictive validity of the perceived strengths-based HR system for employee performance (i.e. task performance and innovative behavior) after controlling for the perceived high-performance work system (HPWS) and perceived high-commitment work system (HCWS).

Study 1 showed that initial fifteen items of the perceived strengths-based HR system appropriately are loaded on one factor and exhibit a good reliability. Study 2 found that there is good discriminant validity between the perceived strengths-based HR system, perceived organizational support, perceived supervisory career support, and work engagement, and the perceived strengths-based HR system exhibits better convergent validity and criteria validity. Study 3 demonstrated that the perceived strengths-based HR system could significantly predict employee performance (i.e. task performance and innovative behavior) even after controlling for perceived HPWS and HCWS.

The current article contributes to advancing HR theory and research and provides a valuable tool for future empirical research on the strengths-based HR system.