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As the complex influencing factors for financing decisions and limited information at the early project stage often render inappropriate financing mode and scheme (FMS) selection in the large-scale urban rail transit (URT) field, this study aims to identify the multiple influencing factors and establish a revised case-based reasoning (CBR) model by drawing on experience in historical URT projects to provide support for effective FMS decisions.

Our research proposes a two-phase, five-step CBR model for FMS decisions. We first establish a case database containing 116 large-scale URT projects and a multi-attribute FMS indicator system. Meanwhile, grey relational analysis (GRA), the entropy-revised G1 method and the time decay function have been employed to precisely revise the simple CBR model for selecting high-similarity cases. Then, the revised CBR model is verified by nine large-scale URT projects and a demonstration project to prove its decision accuracy and effectiveness.

We construct a similarity case indicator system of large-scale URT projects with 11 indicators across three attributes, in which local government fiscal pressure is considered the most influential indicator for FMS decision-making. Through the verification with typical URT projects, the accuracy of our revised CBR model can reach 89%. The identified high-similarity cases have been confirmed to be effective for recommending appropriate financing schemes matched with a specific financing mode.

This is the first study employing the CBR model, an artificial intelligence approach that simulates human cognition by learning from similar past experiences and cases to enhance the accuracy and reliability of FMS decisions. Based on the characteristics of the URT projects, we revise the CBR model in the case retrieval process to achieve a higher accuracy. The revised CBR model utilizes expert experience and historical information to provide a valuable auxiliary tool for guiding the relevant government departments in making systematic decisions at the early project stage with limited and ambiguous project information.

This study examines the implications of real asset liquidity for accounting conservatism. We investigate whether the liquidity of a firm’s physical assets mitigates lenders’ demand for conservatism by increasing the amount lenders can recover if the firm is liquidated, a theoretical prediction in Göx and Wagenhofer (2009).

We use an asset redeployability index as a proxy for firm-level real (physical) asset liquidity and adopt ordinary least squares (OLS) regressions in the test. We also investigate the differential impact of real asset liquidity on conservatism in two unique settings where lenders’ demand for accounting conservatism varies (loan initiation and bank deregulation).

We find that accounting conservatism decreases as real asset liquidity increases. The negative effect of real asset liquidity on conservatism increases as the quantity of the firm’s real assets increases, and the negative association is strengthened when firms face high financing constraints and have access to public debt markets. The moderating effect of real asset liquidity on lenders’ demand for conservatism increases (decreases) when real asset liquidity is more (less) important to lenders.

This study provides direct empirical evidence for the theoretical prediction in Göx and Wagenhofer (2009). Prior research shows that real asset liquidity impacts a firm’s capital structure and investment decisions (Campello and Giambona, 2013; Kim and Kung, 2017; Ortiz-Molina and Phillips, 2014; Williamson, 1988). We complement this literature by providing evidence that real asset liquidity also plays a role in financial reporting by reducing accounting conservatism.

Since the beginning of 2020, COVID-19 has dictated to the world what can be done or not. Log downs of countries, cities and businesses dominated the daily life of everybody. Especially the hospitality and tourism industry went through constant changes in rules and regulations. Tourists were not sure if they were allowed to travel or have to cancel their vacations. Hotels needed to be aware of COVID-19 registration and hygiene. In China, the Zero-COVID policies were wicked, strict and specific and should support daily businesses in the country. A specially used instrument was the variety of QR codes in place to prevent virus outbreaks and monitored tourism movements. For example, the city health QR code of each city/region in China, or the travel QR code to ensure safe travel. This chapter firstly looking into the ideas and policies behind the QR code system in China and secondly discovers through examples its efficiency. The final step is to propose a universal strategy on how QR codes and their policies can support safe and healthy hospitality and tourism recovery during the current pandemic crisis and protect tourists and the hospitality and tourism industry in future pandemic situations.

An improved mathematical programming method for numerical simulation of cloth wrinkling is investigated.

Cloth is modeled as the network of bars (called bar network) or membrane elements with a special nonlinear mechanical constitutive law in the finite element analysis.

Compared with conventional numerical methods, the proposed method does not depend on stress iteration, but on the base exchanges in the solution of a standard quadratic programming problem. Thus, the new method presents very good convergence behavior and accurate predictions of wrinkling patterns and stress distributions of cloths. Numerical results demonstrate the validity and the efficiency of the proposed method.

From the engineering point of view, accurate numerical methods are required in wrinkling analysis of cloth deformation. The algorithm developed here also can be applied into fields such as large deformation under wind load and dynamic behaviors of cloths.

Temperature is an important load for a ballastless track. However, little research has been conducted on the dynamic responses when a train travels on a ballastless track under the temperature gradient. The dynamic responses under different temperature gradients of the slab are theoretically investigated in this work.

Considering the moving train, the temperature gradient of the slab, and the gravity of the slab track, a dynamic model for a high-speed train that runs along the CRTS III slab track on subgrade is developed by a nonlinear coupled way in Abaqus.

The results are as follows: (1) The upward transmission of the periodic deformation of the slab causes periodic track irregularity. (2) Because of the geometric constraint of limiting structures, the maximum bending stresses of the slab occur near the end of the slab under positive temperature gradients, but in the middle of the slab under negative temperature gradients. (3) The periodic deformation of the slab can induce periodic changes in the interlayer stiffness and contact status, leading to a large vibration of the slab. Because of the vibration-reduction capacity of the fastener and the larger mass of the concrete base, the accelerations of both the slab and concrete base are far less than the acceleration of the rail.

This study reveals the influence mechanism of temperature gradient-induced periodic deformation in the dynamic responses of the train-track system, and it also provides a guide for the safe service of CRTS III slab track.

The purpose of this paper on the one hand is to reduce the sintering temperature, shorten the sintering time and improve the electrical properties of the sample through the two-step flash sintering method and on the other hand is to study the effect of electric field on the phase structure, microstructure and electrical properties of the flash sintering sample.

In this paper, (Mg_1/3Ta_2/3)_0.01Ti_0.99O₂ giant dielectric ceramics were prepared by conventional sintering and two-step flash sintering, respectively. Further, the effect of electric field (600–750 V/cm) on the electrical properties of (Mg_1/3Ta_2/3)_0.01Ti_0.99O₂ giant dielectric ceramics was studied.

The results show that compared with the conventional sintering, the sintering temperature of the two-step flash sintering can be reduced by 200°C and the sintering time can be shortened by 12 times. All sintered samples were single rutile TiO₂ structure. Compared with conventional sintering, two-step flash sintering samples have finer grain size. The two-step flash sintered sample has similar dielectric properties to the conventional sintered sample. The dielectric constant of flash sintered samples decreases with the increase of electric field. When the electric field is 700 V/cm, the ceramic sample has the optimal dielectric properties, where the dielectric constant is approximately 5.5 × 10³ and the dielectric loss is about 0.18 at 1 kHz. Impedance spectroscopy analysis shows that the excellent dielectric properties are attributed to the internal barrier layer capacitance model.

This paper not only provides a new method for the preparation of co-doped TiO₂ giant dielectric ceramics but also has great potential in greatly improving efficiency and saving energy.

Role-taking, perspective taking, and empathy have developed through parallel literatures in sociology and psychology. All three concepts address the ways that people attune the self to others’ thoughts and feelings. Despite conceptual and operational overlap, researchers have yet to synthesize existing research across the three concepts. We undertake the task of theoretical synthesis, constructing a model in which role-taking emerges as a multidimensional process that includes perspective taking and empathy as component parts.

We review the literatures on role-taking, perspective taking, and empathy across disciplines. Focusing on definitions, measures, and interventions, we discern how the concepts overlap, how they are distinct, and how they work together in theoretically meaningful ways.

The review identifies two key axes on which each concept varies: the relative roles of affect and cognition, and the relative emphasis on self and structure. The review highlights the cognitive nature of perspective taking, the affective nature of empathy, and the structural nature of role-taking. In a move toward theoretical synthesis, we propose a definition that centers role-taking as a sociological construct, with perspective taking and empathy representing cognition and affect, respectively.

Role-taking is an important part of selfhood and community social life. It is a skill that varies in patterned ways, including along lines of status and power. Theoretical synthesis clarifies the process of role-taking and fosters the construction of effective interventions aimed at equalizing role-taking in interpersonal interaction.

This paper aims to propose a solution for dissolving the “privacy paradox” in social networks, and explore the feasibility of adopting a synergistic mechanism of “deep-learning algorithms” and “differential privacy algorithms” to dissolve this issue.

To validate our viewpoint, this study constructs a game model with two algorithms as the core strategies.

The “deep-learning algorithms” offer a “profit guarantee” to both network users and operators. On the other hand, the “differential privacy algorithms” provide a “security guarantee” to both network users and operators. By combining these two approaches, the synergistic mechanism achieves a balance between “privacy security” and “data value”.

The findings of this paper suggest that algorithm practitioners should accelerate the innovation of algorithmic mechanisms, network operators should take responsibility for users’ privacy protection, and users should develop a correct understanding of privacy. This will provide a feasible approach to achieve the balance between “privacy security” and “data value”.

These findings offer some insights into users’ privacy protection and personal data sharing.

The brake pipe system was an essential braking component of the railway freight trains, but the existing E-type sealing rings had problems such as insufficient low-temperature resistance, poor heat stability and short service life. To address these issues, low-phenyl silicone rubber was prepared and tested, and the finite element analysis and experimental studies on the sealing performance of its sealing rings were carried out.

The low-temperature resistance and thermal stability of the prepared low-phenyl silicone rubber were studied using low-temperature tensile testing, differential scanning calorimetry, dynamic thermomechanical analysis and thermogravimetric analysis. The sealing performance of the low-phenyl silicone rubber sealing ring was studied by using finite element analysis software abaqus and experiments.

The prepared low-phenyl silicone rubber sealing ring possessed excellent low-temperature resistance and thermal stability. According to the finite element analysis results, the finish of the flange sealing surface and groove outer edge should be ensured, and extrusion damage should be avoided. The sealing rings were more susceptible to damage in high compression ratio and/or low-temperature environments. When the sealing effect was ensured, a small compression ratio should be selected, and rubbers with hardness and elasticity less affected by temperature should be selected. The prepared low-phenyl silicone rubber sealing ring had zero leakage at both room temperature (RT) and −50 °C.

The innovation of this study is that it provides valuable data and experience for the future development of the sealing rings used in the brake pipe flange joints of the railway freight cars in China.