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This paper aims at the problem of surrounding rock excavation damage zone of tunneling in the rich water region, this paper aims to propose a new seepage-stress-damage coupling model and studied the numerical algorithm. This reflects the characteristics of rock damage evolution, accompanied by plastic flow deformation and multi-field interaction.

First of all, rock elastoplastic damage constitutive model based on the Drucker–Prager criterion is established, the fully implicit return mapping algorithm is adopted to realize the numerical solution. Second, based on the relation between damage variation and permeability coefficient, the rock stress-seepage-damage model and multi-field coupling solving iterative method are presented. Finally, using the C++ language compiled the corresponding programs and simulated tunnel engineering in the rich water region.

Results show that difference evolution-based back analysis inversed damage parameters well, at the same time the established coupling model and calculating program have more advantages than general conventional methods. Multiple field coupling effects should be more considered for the design of tunnel support.

The proposed method provides an effective numerical simulation method for the construction of the tunnel and other geotechnical engineering involved underground water problems.

This study aims to examine how the effect of pop-ups on an omnichannel brand’s subsequent online sales is moderated by the brand’s online price and premium promotions, paid search and popularity signaling.

Using a difference-in-differences approach, this study appraises variations in two similar Chinese apparel brands’ online sales before and after one of the brands’ implementations of its pop-ups and how the brand’s online promotions modify the pop-ups’ effect.

Unique, interactive pop-ups boost brands’ subsequent online sales. Online price promotions negatively moderate the effect; online premium promotions and paid search positively moderate it. Moreover, the product’s popularity diminishes the extent to which a pop-up stimulates online demand. These findings can be partially generalized to other categories, such as utilitarian products.

Only certain online strategies enhance the effect of pop-ups on brands’ online sales, so practitioners should strategically select appropriate promotion combinations when they operate pop-ups and allocate resources across channels. In addition, the moderating influence of online promotions on pop-ups depends on the type of product being promoted.

Pop-ups offer proven abilities to deliver sensory experiences to online shoppers, reinforce brand awareness and loyalty and boost online sales. This study extends prior research by examining how various online promotions moderate pop-ups’ effects.

The Chinese government hopes to achieve the goal of benefiting citizens by building a National Integrated Online Government Service Platform (NIOGSP). However, citizens' low adoption of the platform makes it difficult for the government to achieve its goal. Research on the influencing factors of citizen adoption of NIOGSP can help the government fully understand the concerns and needs of its citizens and take targeted measures to increase citizen adoption.

First, this research builds a model of the citizen adoption process, including attention, retention and motivation, based on an observational learning model. Next, research variables are determined based on social cognitive theory, literature review and real-world needs. Finally, based on the questionnaire survey and structural equation model, the influencing factors of each stage of the citizen adoption process model are studied and the relationship between the three stages of the model is verified.

Results show that perceived usefulness (PU) and self-efficacy (SE) positively affect attention. SE positively affects retention, while perceived privacy (PP) negatively affects retention. PU, social influence, PP and anxiety positively affect motivation.

The conclusion of this study can provide reference for governments in various countries to establish and improve online one-stop government. In addition, this study verifies the citizen adoption process model and finds that there is no obvious causal relationship between attention and retention, but both have positive effects on motivation.

This study aims to investigate whether and how artificial intelligence (AI) awareness affects work withdrawal.

This survey garners participation from a total of 305 hotel employees in China. The proposed hypotheses are examined using Hayes’s PROCESS macro.

The results indicate that AI awareness could positively affect work withdrawal. Negative work-related rumination and emotional exhaustion respectively mediate this relationship. Furthermore, negative work-related rumination and emotional exhaustion act as chain mediators between AI awareness and work withdrawal.

Given the growing adoption of AI technology in the hospitality industry, it is imperative that managers intensify their scrutiny of the psychological changes experienced by frontline service employees and allocate more resources to mitigating the impact of AI on their work withdrawal.

This study contributes to the burgeoning literature on AI by elucidating the chain mediating roles of negative work-related rumination and emotional exhaustion. It also makes a significant forward in examining mediating mechanisms, notably the chain-mediated mechanism, through which AI awareness impacts employee outcomes.

The rapid growth of emerging market firms (EMFs) has been a topic of interest for the past two decades, especially in China. However, few studies have discussed how and why EMFs can impel the upgrading of their capabilities to quickly win competitive advantages in the global market. In this context, the purpose of this paper is to unravel the implausible upgrading phenomenon from the perspective of technological proximity.

This paper adopts a single case study, specifically that of a leading Chinese e-bike firm, with a special focus on the dynamic nature of the capability upgrading process and underlying mechanisms.

The results show that taking advantage of technological proximity is an important way for EMFs to climb the ladder of capability upgrading. The stage-based process reveals how capability upgrading is achieved through elaborate actions related to technological proximity. Furthermore, this study finds three learning mechanisms behind the technological proximity, which enable firms to successfully upgrade to higher levels of capabilities. In particular, the trigger role played by contextual conditions in guiding firms' capability upgrading is highlighted and characterized.

This study enriches traditional capability upgrading literature from a technological proximity perspective, especially the traditional static upgrading research related to EMFs. The authors also contribute to the conceptualization of technological proximity. However, the research setting is China's e-bike industry; therefore, the study's generalizability to other emerging markets and industries may be limited.

The results show that it is important to recognize the value of the transfer and sharing of technology between proximal industries for local governments. Also, appropriate policies should be developed to break down the technology barriers between these industries. Moreover, rather than catching up with the superior technologies of multinational corporations in advanced countries, focusing on products with high technological proximity in local or regional areas may be more helpful for EMFs' upgrading.

This paper investigates the capability upgrading process and mechanisms in EMFs, particularly with respect to the role played by technological proximity.

The purpose of this paper is to develop feasible composite electrodes with a long cycle life and large specific capacitance and to investigate optimal ratio between aniline and activated carbon materials.

PANI/AC composite electrode materials were synthesised by in situ polymerisation of aniline on activated carbon with ammonium persulphate as oxidant. Hybrid supercapacitors are assembled by putting Ni‐MH battery separator between positive and negative electrodes. The electrochemical performances of PANI/AC composite electrode materials and supercapacitors are studied.

The results show that the optimal ratio between aniline and activated carbon is 1:1.08. The specific capacitance of polyaniline electrode materials is 956 F g⁻¹. The specific capacitance of supercapacitors is 159.37 F g⁻¹. This result could be attributed to the pseudocapacitive effect of Ni(OH)₂. What's more, the activated carbon addition reduced the resistance of polymer electrode materials thus improving the cyclic life.

The supercapacitors can be used in the field of automobiles and can solve the problems of energy shortage and environmental pollutions.

A hybrid supercapacitor, which was immersed in alkaline solution, was assembled by putting Ni‐MH battery separator between two electrodes Ni(OH)₂ as positive electrode and polyaniline composites as negative electrode. In the case of alkaline solution, the capacitive performance of hybrid supercapacitor was improved and excellent.

In the face of fierce international competition for those participating in global value chains (GVCs), upgrading has been a central concern of emerging market firms (EMFs) that are trying to occupy higher value-added positions. However, although the innovation capabilities (ICs) have been generally considered critical to upgrading in GVCs, few studies have examined how IC is built up and then applied to the EMF upgrading process over time. To this end, the purpose of this paper is to investigate why and how EMFs can upgrade in GVCs through the development of their IC.

This paper adopts a multiple-case study of three supplier firms in China and their IC development processes, with a special focus on the nature of the firm-level upgrading in GVCs.

The results generate a process model of EMFs upgrading with respect to the development of IC. The model reveals how IC is built up through the firms' underlying systematic innovation activities, which enable firms to successfully upgrade within GVCs. In particular, the role played by contextual vulnerability in guiding firms to develop the appropriate IC, and the corresponding upgrading, is highlighted.

This study contributes to the micro-foundation in GVCs literature, especially the traditional static upgrading research of EMFs. The authors also contribute to existing IC development research. Meanwhile, the study focuses on the upgrading of three Chinese firms in the phone and LED industries. The generalizability to other emerging markets and industries may therefore be limited.

The study results show that EMFs could initially develop endogenous IC that focuses on process innovation as a means to establish a foundation for further upgrading. In addition, firms need to improve their ability to accurately sense contextual changes. As such, it would be valuable to understand their positions and characteristics within GVCs.

This paper investigates a process model of upgrading in GVCs through IC development in EMFs. This study also adds a dynamic micro-foundation to existing, rather macro and static GVCs studies.

Vehicle companion is one of the most common companion patterns in daily life, which has great value to accident investigation, group tracking, carpooling recommendation and road planning. Due to the complexity and large scale of vehicle sensor streaming data, existing work were difficult to ensure the efficiency and effectiveness of real-time vehicle companion discovery (VCD). This paper aims to provide a high-quality and low-cost method to discover vehicle companions in real time.

This paper provides a real-time VCD method based on pro-active data service collaboration. This study makes use of dynamic service collaboration to selectively process data produced by relative sensors, and relax the temporal and spatial constraints of vehicle companion pattern for discovering more potential companion vehicles.

Experiments based on real and simulated data show that the method can discover 67% more companion vehicles, with 62% less response time comparing with centralized method.

To reduce the amount of processing streaming data, this study provides a Service Collaboration-based Vehicle Companion Discovery method based on proactive data service model. And this study provides a new definition of vehicle companion through relaxing the temporal and spatial constraints for discover companion vehicles as many as possible.

The purpose of this paper is to provide a quantitative assessment on the effect of wall roughness on the pressure drop of fluid flow in microchannels.

The wall roughness is generated by the method of random midpoint displacement (RMD) and the lattice Boltzmann BGK model is applied. The influences of Reynolds number, relative roughness and the Hurst exponent of roughness profile on the Poiseuille number are investigated.

Unlike the smooth channel flow, Reynolds number, relative roughness and the Hurst exponent of roughness profiles play critical roles on the Poiseuille number Po in rough microchannels. Modeling results indicate that, in rough microchannels, the rough surface configuration intensifies the flow-surface interactions and the wall conditions turn to dominate the flow characteristics. The perturbance of the local flows near the channel wall and the formation of recirculation regions are two main features of the flow-surface interactions.

The fluid flow in parallel planes with surface roughness is considered in the current study. In other words, only two-dimensional fluid flow is investigated.

The LBM is a very useful tool to investigate the microscale flows.

A new method (RMD) is applied to generate the wall roughness in parallel plane and LBM is conducted to investigate the pressure drop characteristics in rough microchannels.

The purpose of this paper is to enhance the quadrotor’s capability of short-distance delivery to satisfy the large demand for quadrotor, which is used for goods distribution in huge warehouses, under time-varying payload and external wind disturbance.

A trajectory tracking controller design based on the combination of an adaptive sliding mode control (ASMC) method and the active disturbance rejection control (ADRC) technique is proposed. Besides, an inner–outer loop control system structure is adopted.

Simulation results of different trajectory tracking verify the effectiveness and robustness of the proposed tracking control method under various conditions, including parameter uncertainty and external wind disturbance. The proposed control strategy ensures that quadrotor UAV is capable of tracking linear and spiral trajectory well whether it loads or unloads goods in the presence of the external wind disturbance.

The proposed method of designing a trajectory tracking controller is based on an integral ADRC and ASMC scheme so as to deal with the trajectory tracking problem for a quadrotor with payload variation.