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The purpose of this paper is to propose a wheel/rail mixed lubrication model to study the water lubrication behavior of wheel/rail contact interface.

The numerical simulation method is applied in this paper. A deterministic mixed lubrication model considering surface roughness and transient state is established. The quasi-system numerical and finite difference method are used for numerical solution. The model is verified by comparing with the experimental data in the literature under the same conditions.

Under wet conditions, the change of train speed will change the lubrication state of the wheel/rail contact interface. With an increasing speed, the average film thickness and the film thickness ratio increase, while the adhesion coefficient, the contact load ratio and the contact area ratio decrease. When the creep ratio increases from 0% to 0.5%, the wheel/rail adhesion coefficient and subsurface stress increase sharply. With the increase of axle load, the average film thickness decreases and the adhesion coefficient increases.

This paper aims to improve the mixed lubrication theory by analyzing the characteristics of wheel/rail friction and lubrication, so as to provide some guidance and theory for train driving behavior.

Using the deterministic model, the lubrication state of the wheel/rail contact interface affected by various external factors and the adhesion behavior of wheel/rail progressive process from boundary lubrication to mixed lubrication are studied.

This study considers a Lagrange direct way of modal assurance criterion (MAC) values of an undamped system. The mentioned method for the sensitivity analysis of the MAC of a sliding machine working table is more close to the exact solution and time efficient. The paper aims to discuss these issues.

Using the Lagrange multipliers to compute the first and second-order sensitivity analysis of MAC values.

Because of the Lagrange multiplier without considering the number of design parameters, one only needs to perform the calculation once. Compared with the indirect way, the direct way is more effective when the number of design parameters is greater than one. This calculation procedure is simple and accurate, which can be popularized and used.

Engineering structure often requires only some structure design, and most of the sub-structure design variables are not related to each other. In this case, this way is better and more efficient. The direct way can be applied to the dynamic optimization design of large structures, the frequency and the mode sensitivity analysis in the process of model modification.

Because of the small size and high integration of capacitive micromachined ultrasonic transducer (CMUT) component, it can be made into large-scale array, but this lead to high hardware complexity, so the purpose of this paper is to use less elements to achieve better imaging results. In this research, an optimized sparse array is studied, which can suppress the side lobe and reduce the imaging artifacts compared with the equispaced sparse array with the same number of elements.

Genetic algorithm is used to sparse the CMUT linear array, and Kaiser window apodization is added to reduce imaging artifacts, the beam pattern and peak-to-side lobe ratio are calculated, point targets imaging comparisons are performed. Furthermore, a 256-elements CMUT linear array is used to carry out the imaging experiment of embedded mass and forearm blood vessel, and the imaging results are compared quantitatively.

Through the imaging comparison of embedded mass and forearm blood vessel, the feasibility of optimized sparse array of CMUT is verified, and the purpose of reducing the hardware complexity is achieved.

This research provides a basis for the large-scale CMUT array to reduce the hardware complexity and the amount of calculation. At present, the CMUT array has been used in medical ultrasound imaging and has huge market potential.

The aim of this paper is to examine the effect of organizational environment on engineering project cost management.

Taking China Railway Engineering Corporation 2nd Bureau (CREC 2nd Bureau for short) as an example, the authors conduct lots of semi‐structured interviews in its group corporation, company limited, two subsidiaries and two project departments, and finally collect textual data which include 30 paragraphs and more than 120,000 words. The authors then encode those interview data step by step for further analysis under the research paradigm of grounded theory.

Based on these encoded data, the paper builds concept, basic categories, main categories, which could be the factors affecting the engineering project cost management, the evidence chain and the complete story clue among these categories. Then finally constructs a theoretical framework called “3S” for short, which is comprised of the organizational structure supporting system, the control procedure supporting system and the social relation supporting system.

Because of the insufficient importance placed on engineering project cost management by academics and few theoretical papers, this paper provides a new method for exploring the engineering project cost management and a theoretical reference for further research.

In this paper, the authors discuss the action mechanism of organizational environment in the engineering project cost management and provide for Chinese construction enterprises more explicit guidance on their cost management practice.

There is little research on determinants of engineering project cost by Chinese scholars, which is mainly shown as normative research. There is no perfect theoretical framework on the determinants of engineering project cost management, which is not beneficial to the knowledge of engineering project cost management and is not comprehensive and in depth enough for academics and practitioners. This paper conducts a field study in CREC 2nd Bureau based on grounded theory. At last, “3S” theoretical framework is established. This paper is embodied in using reality as the accordance, scientifically carding and spreading the theory and translating the practical experience into theory, so that it is beneficial for the engineering project cost management.

Detection of hidden defects of aluminum alloy plate with damping coating is a challenging problem. At present, only a few non-destructive testing methods exist to address this engineering problem. Without the restriction of skin effect, remote field eddy current (RFEC) overcomes the interference caused by the damping coating. The RFEC, which has potential advantages for detecting the hidden defects of aluminum plate with damping coating, can penetrate the metal plate to detect buried depth defects. This study aims to test how thick the RFEC sensor can penetrate the metal plate to detect the buried defects.

The magnetic field distribution characteristics are analyzed, the magnetic field intensity distribution is calculated, and the structure and parameters of the coil, magnetic circuit and shielding damping are determined through the two- and three-dimensional finite element simulation methods. Optimal excitation frequency is obtained, and the distance between the excitation coil and detection coil is determined by analyzing the relationship between excitation frequency and remote field points.

Simulation and experimental results verify the feasibility of applying the RFEC detection technology in detecting the hidden defects of aluminum alloy plate with damping coating.

In this paper, the RFEC testing model of hidden defects in aluminum plate sample with damping coating is established by using the finite element method.

The reported Kullback–Leibler (K–L) distance-based generalized grey target decision method (GGTDM) for mixed attributes is an asymmetric decision-making basis (DMB) that does not have the symmetric characteristic of distance in common sense, which may affect the decision-making result. To overcome the deficiency of the asymmetric K–L distance, the symmetric K–L distance is investigated to act as the DMB of GGTDM for mixed attributes.

The decision-making steps of the proposed approach are as follows: First, all mixed attribute values are transformed into binary connection numbers, and the target centre indices of all attributes are determined. Second, all the binary connection numbers (including the target centre indices) are divided into deterministic and uncertain terms and converted into two-tuple (determinacy and uncertainty) numbers. Third, the comprehensive weighted symmetric K–L distance can be computed, as can the alternative index of normalized two-tuple (deterministic degree and uncertainty degree) number and that of the target centre. Finally, the decision-making is made by the comprehensive weighted symmetric K–L distance according to the rule that the smaller the value, the better the alternative.

The case study verifies the proposed approach with its sufficient theoretical basis for decision-making and reflects the preferences of decision-makers to address the uncertainty of an uncertain number.

This work compares the single-direction-based K–L distance to the symmetric one and uses the symmetric K–L distance as the DMB of GGTDM. At the same time, different coefficients are assigned to an uncertain number’s deterministic term and uncertain term in the calculation process, as this reflects the preference of the decision-maker.

Despite an intensified anti-corruption campaign, China's economic growth and social transition continue to breed loopholes and opportunities for big corruption, leading to a money-oriented mentality and the collapse of ethical standards, and exposing the communist regime to greater risk of losing moral credibility and political trust. In Hong Kong, the setting up of the Independent Commission Against Corruption (ICAC) in 1974 marked the advent of a new comprehensive strategy to eradicate corruption and to rebuild trust in government. The ICAC was not just an anti-corruption enforcement agency per se, but an institution spearheading and representing integrity and governance transformation. This chapter considers how mainland China can learn from Hong Kong's experience and use the fight against corruption as a major political strategy to win the hearts and minds of the population and reform governance in the absence of more fundamental constitutional reforms, in a situation similar to Hong Kong's colonial administration of the 1970s–1980s deploying administrative means to minimize a political crisis.

The purpose of this study is to design a long-term vibration monitoring system for track beams of suspended maglev trains to ensure safe and smooth operation of the trains.

The paper begins by focusing on the selection of hardware for the wireless monitoring and acquisition terminal and the circuit design. It connects to a wireless Access Point (AP) via Wi-Fi and utilizes the Transport Control Protocol (TCP) to upload the sensor data collected by the monitoring terminal to the upper computer. Additionally, the design includes software for the upper computer to parse the uploaded data packets and create a visualization interface, which is crucial for monitoring the vibrations of the track beams.

The vibration monitoring system developed in this study can display the data collected by the monitoring terminal in real time on the upper computer, while also allowing remote commands to query the status of the monitoring terminal. Due to the low-power design of the monitoring and acquisition terminal, it is capable of meeting the long-term vibration monitoring requirements for the track beams. Through precision testing of the monitoring terminal, we can ensure that the sensors meet experimental requirements, providing reliable data support for scientific research.

The vibration monitoring system presented in this paper integrates modern wireless communication technology and data visualization technology.

This paper aims to enhance lubrication performance of the pitcher plant–like textured surface with various parameters.

A pitcher plant–like structure surface is fabricated on the copper alloy, and the lubrication performance of the pitcher plant–like structure with various parameters is evaluated. In addition, the pressure distribution and oil film load capacity of the pitcher plant–like surface are simulated based on Navier–Stokes equations.

When the direction of motion aligns with the pitcher plant–like structure, the friction coefficient remains lower than that of the nontextured surface, and it exhibits a decreasing trend with the increasing of the texture width and spacing distance; the lowest friction coefficient (0.04) is achieved with B = 0.3 mm, L = 1.0 mm and θ = 45°, marking a 75% reduction compared to the nontextured surface. Simulation results demonstrate that with the increase in texture width and spacing distance, the oil film load-bearing capacity demonstrates an increasing trend.

Bionic pitcher plants are prepared on the copper alloy to improve the lubrication performance and wear resistance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0119/

The fundamental mission of every green city is to harmonize urban living with environmental preservation. However, a critical challenge arises when the residents of such cities do not share the same level of environmental consciousness, potentially eroding the integrity of the green city’s brand identity. Hence, this study aims to explore the factors influencing residents’ identification with green city branding and assesses how this identification subsequently affects their green citizenship behaviors.

A survey of 1,217 residents from 15 green cities across six countries was conducted and analyzed using SPSS 28.0 for descriptive statistics and PLS-SEM for measurement and structural model analysis.

The results indicate that green city-self connection, green city distinctiveness and environmental benefits significantly impact GCRI, which, in turn, significantly influences green city protection, loyalty and advocacy behaviors. However, green city social and economic benefits did not affect resident identification.

The results of this study provide valuable managerial insights for city brand managers, green city developers and governmental representatives. The study underscores the importance of considering residents as crucial internal stakeholders in the creation of a green city identity that effectively promotes sustainable urban living and an eco-friendly culture.

This study provides theoretical insights into the relationship between green identification and residents’ willingness and commitment to act as ambassadors and promote their city’s green values.