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The purpose of this paper is to present investigations on the significant influence of the tube material and fin density on fluid elastic instability and vortex shedding in a parallel triangular finned tube array subjected to water cross flow.

The experiment was conducted on finned tube arrays with a fin height of 6 mm and fin density of 3 fins per inch (fpi) and 9 fpi. A dedicated setup has been developed to examine fluid elastic instability and vortex shedding. Nine parallel triangular tube arrays with a pitch to tube diameter ratio of 1.78 were considered. The plain tube arrays, coarse finned tube arrays and fine finned tube arrays each of steel, copper and aluminium materials were tested. Plain tube arrays were tested to compare the results of the finned tube arrays having an effective tube diameter same as that of the plain tube.

A significant effect of fin density and tube material with a variable mass damping parameter was observed on the instability threshold. In the parallel triangular finned tube array subjected to water cross flow, a delay in the instability threshold was observed with an increase in fin density. For steel and aluminium tube arrays, the natural frequency is 9.77 Hz and 10.38 Hz, which is close to each other, whereas natural frequency of the copper tubes is 7.40 Hz. The Connors’ stability constant K for steel and aluminium tube arrays is 4.78 and 4.87, respectively, whereas it is 5.76 for copper tube arrays, which increases considerably compared to aluminum and steel tube arrays. The existence of vortex shedding is confirmed by comparing experimental results with Owen’s hypothesis and the Strouhal number and Reynolds number relationship.

This paper’s results contribute to understand the effect of tube materials and fin density on fluid elastic instability threshold of finned tube arrays subjected to water cross flow.

The purpose of this study is to reveal the friction reduction performance and mechanism of granular flow lubrication during the milling of difficult-to-machining materials and provide a high-performance lubrication method for the precision cutting of nickel-based alloys.

The milling tests for Inconel 718 superalloy under dry cutting, flood lubrication and granular flow lubrication were carried out, and the milling force and machined surface quality were used to evaluate their friction reduction effect. Furthermore, based on the energy dispersive spectrometer (EDS) spectrums and the topographical features of machined surface, the lubrication mechanism of different granular mediums was explored during granular flow lubrication.

Compared with flood lubrication, the granular flow lubrication had a significant force reduction effect, and the maximum milling force was reduced by about 30%. At the same time, the granular flow lubrication was more conducive to reducing the tool trace size, repressing surface damage and thus achieving better surface quality. The soft particles had better friction reduction performance than the hard particles with the same particle size, and the friction reduction performance of nanoscale hard particles was superior to that of microscale hard particles. The friction reduction mechanism of MoS₂ and WS₂ soft particles is the mending effect and adsorption film effect, whereas that of SiO₂ and Al₂O₃ hard particles is mainly manifested as the rolling and polishing effect.

Granular flow lubrication was applied in the precision milling of Inconel 718 superalloy, and a comparative study was conducted on the friction reduction performance of soft particles (MoS₂, WS₂) and hard particles (SiO₂, Al₂O₃). Based on the EDS spectrums and topographical features of machined surface, the friction reduction mechanism of soft and hard particles was explored.

This study aims to investigate mechanisms and boundary conditions of the impact of customer engagement strategies (CESs) on customer loyalty (CL) based on goal-framing and well-being theory.

Through a three-stage, time-lagged research design, 246 valid samples were obtained. This study tested and validated the proposed framework using hierarchical regression analysis and a moderated mediation procedure.

First, CESs have a significant positive impact on CL. Second, consumer well-being (CWB) partially mediates the CESs–CL relationship. Third, information processing style (IPS) moderates the impact of CESs on CWB, with a more pronounced effect observed under the affective processing style. Finally, IPS further moderates the indirect effect of CESs on CL, indicating that CESs enhance CL through increased CWB, particularly under the affective processing style.

Revealing the pivotal role of CESs in enhancing CL at the corporate level helps bridge the gap between companies and customers, thereby facilitating the establishment of long-term cooperative relationships. Additionally, introducing the concept of CWB into the study of CL offers a novel perspective for understanding customer behavior.

This study examines the antecedents and dynamics of authoritarian leadership and extends the effects of managers' sleep quality to employee behavior.

On the basis of self-regulation theory, 513 unit day samples were analyzed using cross-level path analysis and a Monte Carlo simulation test.

Managers' sleep quality is positively related to authoritarian leadership and positive emotions play a mediating role. Authoritarian leadership is positively related to employees' counterproductive behavior. Managers' sleep quality affects employees' counterproductive behavior through managers' positive emotions and authoritarian leadership.

Individuals should learn to reduce stress and maintain a positive mood. Organizations should reduce employees' overtime work and work stress and find other ways to improve employees' sleep quality.

First, we considered authoritarian leadership to be dynamic and studied it on a daily basis. Second, we studied the antecedents of authoritarian leadership from the perspective of leaders' states (sleep quality and emotions). Third, we discussed the effect of managers' sleep quality on employee behavior.

Hospitality and tourism research lags in using experimental designs. This study aims to reveal prestigious scholars’ opinions and suggestions on how to effectively design and execute experimental research.

The authors conducted an open-ended survey on 187 editors and editorial board members from 22 top hospitality and tourism journals. Their answers were coded following an inductive method of coding, and a list of themes and categories was synthesized.

The results summarize common problems of this method and indicate significant barriers to making experimental studies publishable. The review criteria for experimental studies are presented from four aspects: overall design, stimuli and manipulations, data collection and reporting results.

The results provide valuable suggestions for researchers interested in experimental design in the hospitality and tourism field. The study contributes to a shift toward well-designed and well-executed experimental research in hospitality and tourism.

To the best of the authors’ knowledge, the study is the first to survey editorial board members of impactful hospitality and tourism journals to reveal their insights into the experimental methodology. The study makes significant theoretical and methodological contributions by addressing calls to understand common problems and barriers to experimental research in our field.

The study aims to investigate the impact of indirectly evoked incentives, in the form of supervisor’s preferences, on the decision about accounting policy regarding depreciation method selection and to examine subsequent post-decision distortion by evaluating the depreciation method.

The authors conducted two experiments with control and treatment groups, manipulating the supervisor’s indirectly evoked preferences. In Study 2, the authors also measured the evaluation of both depreciation methods to investigate post-decisional distortion regarding the assessment of the depreciation method chosen in a decision task. Study 1 was conducted among 85 accounting students, while Study 2 consisted of 200 accountants.

Both studies revealed the significant impact of supervisor’s indirectly evoked preferences on accounting policy decisions. Participants who were aware of supervisors’ preferences were more likely to choose the depreciation method that was consistent with those preferences. The authors also found that those participants attached a higher value to the depreciation method, providing evidence that adherence to the supervisor’s preferences results in a distorted assessment of the depreciation methods.

First, this study shows that indirectly evoked supervisors’ preferences may lead to a departure from substantive criteria resulting in low-quality accounting outcomes. Second, the assessment of the depreciation method is inseparable from the situational context, as the evaluation of the depreciation method is interdependent upon the preferences of the choice of a depreciation method and the fulfillment of those preferences.

Explore how the degree of humanization affects user misconduct, and provide effective misconduct prevention measures for the wide application of artificial intelligence in the future.

Based on the “Uncanny Valley theory”, three experiments were conducted to explore the relationship between the degree of humanization of service machines and user misbehavior, and to analyze the mediating role of cognitive resistance and the moderating role of social class.

There is a U-shaped relationship between the degree of humanization of service machines and user misbehavior; Social class not only regulates the main effect of anthropomorphism on misbehavior, but also regulates the intermediary effect of anthropomorphism on cognitive resistance, thus affecting misbehavior.

The design of the service robot can be from the user’s point of view, combined with the user’s social class, match different user types, and provide the same preferences as the user’s humanoid service robot.

This study is an important reference value for enterprises and governments to provide intelligent services in public places. It can prevent the robot from being vandalized and also provide users with a comfortable human-computer interaction experience, expanding the positive effects of providing smart services by government and enterprises.

This study avoids and reduces users' misbehavior towards intelligent service robots, improves users' satisfaction in using service robots, and avoids service robots being damaged, resulting in waste of government, enterprise and social resources.

From the perspective of product factors to identify the inducing factors of improper behavior, from the perspective of social class of users to analyze the moderating effect of humanization degree and user improper behavior.

The purpose of this study is to examine the formation of sustainable development competencies (SDCs) in future primary school teachers during English for specific purposes classes, and to assess the correlation between English proficiency and the development of SDCs, including Collaboration, Strategic thinking, Critical thinking, Modelling sustainable behaviour, Systems thinking and Future thinking.

The research experiment involved the application of content and language integrated learning and facilitation methods in three higher education institutions in Ukraine. The students’ level of English language proficiency was assessed based on the results of the online Cambridge English Language Assessment test, while the level of SDC formation was measured using research methods adapted to the Ukrainian context.

The experiment revealed positive changes in the levels of SDCs and English language proficiency through integrated learning and the application of facilitation methods.

The study established a correlation between the level of English language proficiency and the formation of competencies, such as Collaboration, Strategic thinking, Critical thinking, Modelling sustainable behaviour, Systems thinking and Future thinking, all of which are vital for sustainable development.

For ranking aggregation in crowdsourcing task, the key issue is how to select the optimal working group with a given number of workers to optimize the performance of their aggregation. Performance prediction for ranking aggregation can solve this issue effectively. However, the performance prediction effect for ranking aggregation varies greatly due to the different influencing factors selected. Although questions on why and how data fusion methods perform well have been thoroughly discussed in the past, there is a lack of insight about how to select influencing factors to predict the performance and how much can be improved of.

In this paper, performance prediction of multivariable linear regression based on the optimal influencing factors for ranking aggregation in crowdsourcing task is studied. An influencing factor optimization selection method based on stepwise regression (IFOS-SR) is proposed to screen the optimal influencing factors. A working group selection model based on the optimal influencing factors is built to select the optimal working group with a given number of workers.

The proposed approach can identify the optimal influencing factors of ranking aggregation, predict the aggregation performance more accurately than the state-of-the-art methods and select the optimal working group with a given number of workers.

To find out under which condition data fusion method may lead to performance improvement for ranking aggregation in crowdsourcing task, the optimal influencing factors are identified by the IFOS-SR method. This paper presents an analysis of the behavior of the linear combination method and the CombSUM method based on the optimal influencing factors, and optimizes the task assignment with a given number of workers by the optimal working group selection method.

Due to the miniaturization of electronic devices, the increased current density through solder joints leads to the occurrence of electromigration failure, thereby reducing the reliability of electronic devices. The purpose of this study is to propose a finite element-artificial neural network method for the prediction of temperature and current density of solder joints, and thus provide reference information for the reliability evaluation of solder joints.

The temperature distribution and current density distribution of the interconnect structure of electronic devices were investigated through finite element simulations. During the experimental process, the actual temperature of the solder joints was measured and was used to optimize the finite element model. A large amount of simulation data was obtained to analyze the neural network by varying the height of solder joints, the diameter of solder pads and the magnitude of current loads. The constructed neural network was trained, tested and optimized using this data.

Based on the finite element simulation results, the current is more concentrated in the corners of the solder joints, generating a significant amount of Joule heating, which leads to localized temperature rise. The constructed neural network is trained, tested and optimized using the simulation results. The ANN 1, used for predicting solder joint temperature, achieves a prediction accuracy of 96.9%, while the ANN 2, used for predicting solder joint current density, achieves a prediction accuracy of 93.4%.

The proposed method can effectively improve the estimation efficiency of temperature and current density in the packaging structure. This method prevails in the field of packaging, and other factors that affect the thermal, mechanical and electrical properties of the packaging structure can be introduced into the model.