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In order to extend the application of the original octagonal Goodman–Smith fatigue limit diagram, which is commonly used for the evaluation of structure fatigue stress in engineering, a modification of it is proposed for the structure made of S355 steel (commonly used in high-speed electric multiple units (EMUs) bogie frame).

The modification is made based on Deutscher Verband für Schweißen und verwandte Verfahren e. V. (DVS) 1612 standard and the γ-P-S-N curve, with consideration of the fatigue evaluation requirements of different survival rates and confidence levels. The verification of the modification is performed for three welded joints and for the comparison with the experimental data.

The results indicate that the design survival rate, the design safety margin and the fatigue stress evaluation of welded joint types are all improved by using the modified diagram.

There are relatively few studies on modifying octagonal Goodman–Smith fatigue limit diagram. In this paper, a modified diagram is proposed and applied in order to ensure the safety and durability of key welded structures of rail vehicles.

Urban green spaces support people to approach active, healthy ageing, especially in high-density cities where they compensate for limited private living spaces. This research paper aims to examine how urban green spaces support active, healthy ageing by exploring correlations between behaviour, physical setting and gender difference among older people in a highly populated urban context.

Urban parks in older neighbourhoods of Macau were selected for data collection. Photographic documentation was used to collect data, with 1,201 older people photographed identified as valid samples. Each was coded according to labels of behaviour, physical setting and gender. Chi-squared tests were conducted to assess correlations between behaviours and features of physical settings, and differences between genders in behaviours and physical settings. Logistic regression analysis was conducted to further examine associations between older people's behaviours and features of physical settings by gender.

The research reveals types and frequency of behaviours displayed, preferred environmental features for different behaviours and gender differences in behaviours and preferred environmental features. Design principles targeting active, healthy ageing should consider particular amenities and street furniture, the arrangement of trees and landscapes and the integration of open and secluded places.

Previous studies address older people's behaviour from the perspective of either environmental influence or gender difference, but there have been few studies on gendered behavioural differences among older people in urban green spaces. Analysing the behaviour–physical setting–gender relationship provides more evidence in the field of built environment studies.

This study investigates how role overload in the sharing economy leads to emotional exhaustion, which restricts value co-creation activity, and also investigates the moderating effect of perceived platform support.

Two experimental investigations and field research questionnaires were given to respondents with shared mobility industry expertise.

First, role overload detrimentally affects service providers' value co-creation behavior; second, emotional exhaustion acts as a mediator between role overload and value co-creation behavior; and finally, perceived platform support moderates the adverse effect of role overload on emotional exhaustion.

To the best of the authors' knowledge, this study is the first to explore the antecedents of value co-creation behavior from the service provider's perspective, extending the application of COR theory in a sharing economy context.

First, alternative mediators between role overload and emotional exhaustion were not identified. Second, other dimensions of role overload and their impacts were not examined. Lastly, this study did not explore broader perspectives beyond algorithms.

This study recommends that managers reduce role overload ex ante in terms of clarifying responsibilities and obligations, providing substantive resource support and rationalizing order allocation, respectively.

The purpose of this paper is to investigate the thermal elastohydrodynamic lubrication (TEHL) flash temperature of the helical gear pairs considering profile modification.

A flash temperature model of the helical gear pair considering the profile modification is proposed based on the TEHL and meshing theories. In doing so, the slicing, fast Fourier transform and chase-after methods are applied to accurately and rapidly obtain the flash temperature of the gear pair. Then, the effects of the modification, input torque and rotation speed on the flash temperature are studied.

With the increment of the tip relief amount, the flash temperature of the helical gear pair with the axial modification decreases first and then increases, and the meshing position of the maximum flash temperature moves toward the pitch point. Moreover, reducing the input torque or increasing the rotation speed can efficiently reduce the TEHL flash temperature.

This work is a valuable reference for the profile design and optimization of the helical gears to avoid the excessive flash temperature.

In this paper, the smoothed point interpolation method (SPIM) is used to model the slope deformation. However, the computational efficiency of SPIM is not satisfying when modeling the large-scale nonlinear deformation problems of geological bodies.

In this paper, the SPIM is used to model the slope deformation. However, the computational efficiency of SPIM is not satisfying when modeling the large-scale nonlinear deformation problems of geological bodies.

A simple slope model with different mesh sizes is used to verify the performance of the efficient face-based SPIM. The first accelerating strategy greatly enhances the computational efficiency of solving the large-scale slope deformation. The second accelerating strategy effectively improves the convergence of nonlinear behavior that occurred in the slope deformation.

The designed efficient face-based SPIM can enhance the computational efficiency when analyzing large-scale nonlinear slope deformation problems, which can help to predict and prevent potential geological hazards.

The purpose of this paper is to quantify the influence of alternating current (AC) interference on hydrogen evolution reaction of X80 steel.

The hydrogen evolution potential was obtained by cathodic potentiodynamic polarization curve. The instantaneous potential under AC interference was obtained by high-frequency acquisition with three-electrode system. Electrochemical impedance spectroscopy and Tafel polarization curves were used to study the influence mechanism of AC interference on instantaneous potential.

It was concluded that the hydrogen evolution reaction could occur on X80 steel under AC interference. There were critical AC current densities of about 100 to 200 A/m2, beyond which the cathode reaction of X80 steel changed from oxygen absorption to hydrogen evolution. Besides the pH value, the initial polarization potential EZ and impedance module of the steel/electrolyte interface under AC interference were also the factors that affected the critical AC densities in different solutions.

This research quantified the hydrogen evolution capacity of X80 steel under AC interference, which could be applied to clear the effect of AC interference on hydrogen evolution reaction.

With the increasing abundance of network resources and big data, multi-modal information search (MMIS) has been paid more and more attention, but the research results of MMIS are relatively few. This paper attempts to put forward constructive suggestions for the design of multi-modal information system, so that the system can have a better user experience, help users improve the efficiency of obtaining information and optimize the information service mode.

A research model of influencing factors is established by using the TAM (technology acceptance model) theory. The influencing factors of users' multi-modal information search behavior (MMISB) are analyzed by using questionnaire, experiment and the structural equation model. On the basis of this, some suggestions are put forward to build the multi-modal search (MMS) system and improve the efficiency of MMIS.

The research shows that users' MMISB is directly related to their search intention, and the search intention can influence users' cognition of the usefulness and ease of MMIS through their own information search ability and system characteristics. The user's MMIS ability is affected by the demand expression ability and retrieval ability cognition; the user's cognition of system characteristics is affected by the system function and information quality. This shows that the user's MMISB is closely related to the user's cognitive situation, but due to the author's limited time and research ability, only the questionnaire survey method cannot be used to in-depth research and explore the influencing factors of MMIS. Therefore, in the future research, we should combine the interview method to further track the user's emotional factors and scene factors.

For the first time, TAM theory is combined with cross-modal retrieval behavior and the paper explores the influencing factors and evaluation indexes of users' MMISB. The second, the questionnaire was compiled to investigate the influencing factors of the MMISB of the university group, and the reliability analysis, validity analysis, correlation analysis and structural equation model analysis of the survey data are carried out . The survey data and analysis results are original, which can provide a theoretical basis for improving the service level of MMIS.

Collaboration is essential to BIM-enabled construction projects (BECPs). To facilitate collaboration, various strategies have been proposed. Usually, project team adopts single collaboration strategy for convenience. However, BIM-based collaboration is rather dynamic and exposed to a lot of barriers and risks, which easily changes collaboration conditions among partners. Therefore, better understanding of collaboration conditions in BECPs is crucial to develop flexible and suitable strategies. To fill in the gap, this study intends to identify typical collaboration profiles in BECPs and develop a profile-oriented strategy selection framework.

This study establishes a six-dimensional collaborative behavior matric based on a comprehensive literature review to profile collaboration. Then a questionnaire survey is conducted to collect the collaboration data from 162 BECPs in China. Finally, latent profile analysis (LPA) is utilized to identify the typical collaboration profiles in BECPs.

Through LPA, four profiles are identified, including restricted collaboration profile, smarmy collaboration profile, intuitive collaboration profile, and modest collaboration profile. A profile-oriented strategy selection framework is also established to match strategies with collaboration profiles. Two major categories of strategies are proposed to promote these collaboration profiles including trust building and elevating strategies and collaborative behaviors facilitating strategies.

These identified profiles can provide an insightful understanding on the diversified collaboration conditions in BECPs.

The profile-oriented strategy selection framework will help managers develop strategies flexibly to promote collaboration in BECPs.

This study validates four typical collaboration profiles in BECPs. Moreover, a profile-oriented strategy selection framework is also established for collaboration facilitation in BECPs.

This study explores how collaborative cost sharing between the buyer and the supplier in cold chain equipment and marketing and advertising affects the performance of a fresh agricultural produce supply chain (FAP-SC).

We use a contingency approach to modeling different scenarios and analyzing how fairness perception, interplaying with corporative–retailer cost sharing., influences the performance of fresh agricultural produce cold chains.

The findings of the research highlight the crucial role of the retailer's fairness concern. When the retailer's fairness concern is absent, cost sharing (in cold chain equipment and marketing and advertising) is found to help boost demand and enhance the profits of members of the supply chain; bilateral cost sharing is found to have a more significant impact than unilateral cost sharing. When the retailer's fairness concern is taken into account, however, cost sharing is found to reduce demand at a lower level of fairness coefficient but increases demand at a higher level of fairness coefficient; bilateral cost sharing boosts both demand and profit of the supply chain when the retailer is in a “high concern, high anger” state.

The findings of the research highlight the important role of the buyer's farness perception when supply chain partners adopt collaborative cost sharing programs. This study contributes significantly to research and practice in supply chain collaboration and agricultural cold chain performance.

Abutment damage in liquefied ground is an important form of seismic damage of bridge structure. This paper aims to further research the effect of beam restriction on seismic damage mode of abutment in liquefied ground.

Based on the investigation of the seismic damage of Shengli Bridge in Tangshan earthquake, the finite element software dynamic effective stress analysis for ground (UWLC) is used to simulate the seismic damage of Shengli Bridge, and the results were compared with the actual seismic damage results. Then, the influences of the horizontal binding force of the beam, the liquefaction layer thickness, the top weight of the abutment, the peak acceleration, the liquefaction layer buried depth and the type of the foundation soil on the abutment seismic damage model are studied.

The results show that numerical simulation results are consistent with the actual seismic damage, and it is feasible to use UWLC software to simulate seismic damage. The results show that the seismic failure mode of the gravity abutment in liquefied ground is slip–rotation coupling type, not single slip type or rotation type. The large deformation of abutment bottom layer, horizontal binding force of the beam and post-stage soil pressure are the main reasons for abutment rotation or even destruction.

A series of basic assumptions are used in the calculation process in this paper. The gravity abutment is defined as the elastic body and neglects its local deformation. The soil layer is a homogeneous isotropic. The consolidation process and the drainage boundary problem are not considered in the calculation process. Therefore, the paper may have some limitations.

To further research the seismic damage mode and influencing factors of abutment in liquefied ground, in this paper, based on the investigation of the seismic damage of Shengli Bridge in Tangshan earthquake, the finite element software UWLC is used to simulate the seismic damage of Shengli Bridge, and the results were compared with the actual seismic damage results. The seismic damage mode and influencing factors of gravity abutment in liquefied ground have been studied.