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The purpose of this paper is to reduce the drag loss and study the effects of operating conditions and groove parameters such as flow rate and temperature of automatic transmission fluid, clearance between plates, groove depth and groove ratio on the drag torque of a wet clutch for vehicles, parametric analysis of the drag torque model of wet multi-plate friction clutch with groove consideration.

Both experimental and numerical research was carried out in this work. Parametric groove models, full film lubrication flow model and pressure distribution model are established to investigate the effects of the grooves on drag torque of a wet clutch. Multigrid method is used to simplify the solution.

In this paper, a drag torque model of a wet multi-plate friction clutch based on the basic theory of viscous fluid dynamics is examined through experimental and numerical methods that take grooves into account, and the change trend of drag torque with operating conditions and groove parameters is analyzed.

Multigrid method is used to solve the governing equations, which simplifies the solution process because of the restrictions and interpolation operations between the adjacent layers of coarser and fine grids. These works provide insight into the effect regularity of operating conditions and groove parameters on drag torque of a wet multi-plate friction clutch. Furthermore, variable test conditions and sufficient experimental data are the main functions in the experimental research.

As megaprojects bear extensive and profound social responsibilities throughout the project life cycle, formulating effective measures for improving construction enterprise social responsibility is key to project success. Given the current research is relatively lack of these measures, this study aims to formulate a meta-network framework to improve the megaproject social responsibility behaviour (MSRB) for construction enterprises.

First, this study implements literature review, expert interview and field investigation to identify the construction enterprise MSRB and its influencing factors. Second, this study evaluates the MSRB implementation level of the selected construction enterprises and proposes the above mentioned meta-network framework. Next, this meta-network is configured to reflect the impact of MSRB strategic adjustment. Last but not least, a real-world case study is carried out to validate this framework.

The best MSRB performance is always witnessed from the contractor group, followed by the project client group and the site supervisor group. The outcomes of implementing certain managerial strategies indicate that (1) social responsibility cognition is a critical factor for all the groups; (2) communication mechanism and normative pressure are the critical factors for clients; (3) coercive pressure is a critical factor for supervisors and (4) cultural cognitive pressure is a critical factor for clients and contractors.

The use of the framework in proactive assessment and management of MSRB can lead to effective strategies for construction enterprises to increase the efficiency and quality of projects.

The paper aims to provide a facile approach to the synthesis of polyurethane–silica nanocomposites by introducing self-made aqueous silica sols with different particle sizes into polyurethane materials. This paper investigates the effects of the silica nanoparticles on the polyester polyol, as well as the physical properties and transmittance of the hybrid polyurethane coatings.

Colloidal silica particles of different sizes were obtained using a sol–gel process and were then embedded into polyester polyol by in-situ polymerization. These polyester polyol–silica resins were synthesized using an azeotrope process, using xylene to remove the water generated in the system and present in the dispersion medium for the colloidal silica. The polyester polyol–silica resins were further cured using isocyanate trimers to form polyurethane–silica hybrid films.

The paper observed that the viscosity of the polyester polyol–silica nanocomposite resins increased and their appearance changed from transparent to ivory white as the particle size of the added silica was increased. It was found that increasing the hydroxyl content of the silica improved the film transmittance in the visible light region. However, the transmittance decreased sharply once the diameter of the silica particles reached 100 nm.

Because of the limitation of experimental conditions, some performances have not been tested. Therefore, researchers are encouraged to conduct further tests.

The paper provides a method of preparing hybrid polyurethane film by using silica; the results indicate that the introduction of nano-silica can improve the wear resistance and glass transition temperature of polyurethane coatings.

The results obtained in this study will be extremely useful to enhance the understanding of organic–inorganic hybrid materials.

The alienation of megaproject environmental responsibility (MER) behavior is destructive, but its mechanism has not been clearly depicted. Based on fraud triangle theory and the fuzzy set qualitative comparative analysis (fsQCA) method, this study explored the combined effect of antecedent factors on alienation of MER behavior.

Based on the fraud triangle theory and literature review, eight influencing factors associated with the alienation of MER behavior were first identified. Subsequently, the fuzzy-set qualitative comparative analysis was used in this study to reveal configurations influencing alienation of MER behavior.

The study found nine configurations of MER behavioral alienation antecedent factors, integrated into three types of driving modes, i.e. “economic pressure + learning effect,” “institutional defect + moral rejection,” and “information asymmetry + economic pressure + expectation pressure.”

By analyzing the configuration effects of various induced conditions, this study puts forward a comprehensive analysis framework to solve the alienation of MER behavior in the megaprojects and a practical strategy to control alienation of MER behavior.

Distinguishing phishing emails from legitimate emails continues to be a difficult task for most individuals. This study aims to investigate the psycholinguistic factors associated with deception in phishing email text and their effect on end-user ability to discriminate phishing emails from legitimate emails.

Email messages and end-user decisions collected from a laboratory phishing study were validated and analyzed using natural language processing methods (Linguistic Inquiry Word Count) and penalized regression models (LASSO and Elastic Net) to determine the linguistic dimensions that attackers may use in phishing emails to deceive end-users and measure the impact of such choices on end-user susceptibility to phishing.

We found that most participants, who played the role of a phisher in the study, chose to deceive their end-user targets by pretending to be a familiar individual and presenting time pressure or deadlines. Results show that use of words conveying certainty (e.g. always, never) and work-related features in the phishing messages predicted higher end-user vulnerability. On the contrary, use of words that convey achievement (e.g. earn, win) or reward (cash, money) in the phishing messages predicted lower end-user vulnerability because such features are usually observed in scam-like messages.

Insights from this research show that analyzing emails for psycholinguistic features associated with computer-mediated deception could be used to fine-tune and improve spam and phishing detection technologies. This research also informs the kinds of phishing attacks that must be prioritized in antiphishing training programs.

Applying natural language processing and statistical modeling methods to analyze results from a laboratory phishing experiment to understand deception from both attacker and end-user is novel. Furthermore, results from this work advance our understanding of the linguistic factors associated with deception in phishing email text and its impact on end-user susceptibility.