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By aiming at defending cascade failures effectively, the purpose of this paper is to present a strategy of inserting modular topologies into urban road network through reducing the burdens of critical components with too much traffic flow.

Each module is considered as a small-world random network, which is inserted into the initial Barabási-Albert scale-free network. Based on the user-equilibrium assignment, the strategy searches for remote nodes with low betweeness and flow in the network, and sets these nodes to be connected with the modular topologies. In this sense, the inserted modules are supposed to attach to the nodes with lower intensity of shorter path, and avoid bringing more impact to the nodes with higher betweeness and traffic flow. By using efficiency as the measurement of cascading failures, the performance of the networks generated through the strategy is tested.

The results show that the performance of the strategy is sensitive to the average degree of the inserted modular, and the modular size with a better effect on reducing the size of cascading failures or delaying the time of breakdown, while the other factors (e.g. the rewired probability) present few differences among various values. Meanwhile, it is found that the importance-based attachment mechanism has a better effect on preventing the cascading failures, especially delaying the step time of the larger reduction.

The strategy aims at alleviating the burdens in critical components to prevent the cascading failures of the network, and provides practical guidance on the decision of the urban road network evolving process.

An effective strategy for cascade defense in urban road network is proposed in this paper.

This study examines how maturity mismatch, a specific type of financial structure of firms, affects corporate outward foreign direct investment (OFDI).

Using the number of newly established foreign subsidiaries in a given year as firm-level OFDI and utilizing data from Chinese listed firms between 2007 and 2022, we employ a negative binomial regression model to examine the impact of corporate maturity mismatch on the OFDI. We also make efforts to ensure the robustness of the result, such as employing an exogenous policy to establish a difference-in-difference model.

The empirical result indicates that maturity mismatch inhibits firms' OFDI. Additional test shows that maturity mismatch increases firms' financing costs and reduces firms' research and development (R&D) investment and that the negative impact of maturity mismatch on OFDI is predominantly observed in firms with high financial constraints and low R&D intensity, indicating that maturity mismatch may affect firms' OFDI through the financing cost channel and the R&D investment channel.

Corporate maturity mismatch is common in China and similar emerging markets. However, research on the economic consequences of maturity mismatch, especially its impact on firms' overseas expansions, is rare. This study establishes the relationship between corporate maturity mismatch and OFDI, contributes to the literature on the relationship between financial factors and OFDI, and provides policy implications for emerging market countries.

This paper aims to propose a method for finding the maximum rotational speed of an inclined turntable at which the stability of the bearing oil film is maintained.

The finite difference method was used to solve the Reynolds equation. Variation of bearing capacity of a tilted hydrostatic turret over time was determined. The combined effect of tilt and rotational speed of the turret on the oil film stability was also analyzed.

When the turntable is operated at low speeds with only small angle of tilt, stability of the oil film is maintained. At lower rotational speeds, a smaller angle of tilt improves the bearing capacity and ensures stability of the oil film. Whereas, higher rotational speeds can have a considerable influence on the bearing capacity.

The results demonstrate that the inclination or tilt of the turntable significantly affects the stability of the oil film.

Scholars have examined the possible relationship between information technology (IT) and organizational agility. Although the general-level effect of IT is undisputed, empirical research on how different types of IT contribute to various aspects of organizational agility remains scarce. Therefore, this study aims to propose an integrated framework of internal capability and external environment to address this research gap.

This study investigates the potential mediating effects of absorptive capacity and the moderating effects of information intensity in the IT‒agility relationship. With a dataset comprising 165 organizations in China, this work provides empirical evidence that the effects of absorptive capacity and information intensity are multifaceted and nuanced, thereby revealing the latent mechanisms of IT competency and organizational agility.

Absorptive capacity partially mediates the effects of IT knowledge and IT operations on market capitalizing agility and fully mediates their effects on operational adjustment agility. However, no direct or indirect effects of IT objects are found on both types of organizational agility. Information intensity also positively moderates the effects of IT operations and IT objects on absorptive capacity. However, no significant moderation is found with regard to IT operations.

This study provides novel insights by demonstrating clearly the different mediating roles of absorptive capacity in the relationship among various types of IT competency and diverse aspects of organizational agility. This work also underscores the moderating role of information intensity in shaping absorptive capacity through IT competency.

Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve.

A shape model for the CA process is established in this study. Specifically, a virtual shapemeter and closed-loop control system based on the advanced parameter acquisition system and information transmission of CA units are developed in C++ programming language. This system realises real-time dynamic shape display, closed-loop control and shape prediction by collecting raw data of steel coils and parameters during CA.

Field test results show that the shape predicted by the virtual shapemeter coincides with the measured shape by over 90 per cent, which fully meets the precision requirement of industrial applications.

Moreover, shape quality is effectively improved without increasing hardware investments.

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.

This paper aims to present the mathematical formulations of a magnetic inverse problem for the electric arc current density reconstruction in a simplified arc chamber of a low-voltage circuit breaker.

Considering that electric arc current density is a zero divergence vector field, the inverse problem can be solved in Whitney space W² in terms of electric current density J with the zero divergence condition as a constraint or can be solved in Whitney space W¹ in terms of electric vector potential T where the zero divergence condition naturally holds. Moreover, the tree gauging condition is applied to ensure a unique solution when solving for the vector potential in space W¹. Tikhonov regularization is used to treat the ill-posedness of the inverse problem complemented with L-curve method for the selection of regularization parameters. A common mode approach is proposed, which solves for the reduced electric vector potential representing the internal current loops instead of solving for the total electric vector potential. The proposed inversion approaches are numerically tested starting from simulated magnetic field values.

With the common mode approach, the reconstruction of current density is significantly improved for both formulations using face elements in space W² and using edge elements in space W¹. When solving the inverse problem in space W¹, the choice of the regularization operator has a key role to obtain a good reconstruction, where the discrete curl operator is a good option. The standard Tikhonov regularization obtains a good reconstruction with J-formulation, but fails in the case of T-formulation. The use of edge elements requires a tree-cotree gauging to ensure the uniqueness of T. Moreover, additional efforts have to be taken to find an optimal regularization operator and an optimal tree when using edge elements. In conclusion, the J-formulation is to be preferred.

The proposed approaches are able to reconstruct the three-dimensional electric arc current density from its magnetic field in a non-intrusive manner. The formulations enable us to incorporate a priori knowledge of the unknown current density into the solution of the inverse problem, including the zero divergence condition and the boundary conditions. A common mode approach is proposed, which can significantly improve the current density reconstruction.

This study aims to improve the maneuverability and stability of four-wheel chassis in a small paddy field; a front axle swing steering four-wheel chassis with optimal steering is designed.

When turning, the front inner wheel stops and the rear inner wheel is in the following state. The hydraulic drive system of the walking wheel adopts a driving mode in which two front-wheel motors are connected in series and two rear wheel motors in parallel. The chassis uses a combination of a gasoline engine with a water cooling system, a CVT continuously variable transmission and a hydraulic drive system to increase the control capability. The front axle rotary chassis adopts a step-less variable speed engine and a hydraulic control system to solve the hydraulic stability of the chassis in uphill and downhill conditions so as to effectively control the over-speed of the wheel-side drive motors. Through the quadratic orthogonal rotation combination design test, the mathematical models of uphill and downhill front-wheel pressures and test factors are established.

The results show that the chassis stability is optimal when the back pressure is 0.5 MPa, and the rotating slope is 4°. The uphill and downhill pressures of the front wheels are 2.38 MPa and 1.5 MPa, respectively.

The influence of external changes on the pressure of hydraulic motors is studied through experiments, which lays the foundation for further research.

Accurate presentation of the rock microstructure is critical to the grain-scale analysis of rock deformation and failure in numerical modelling. 3D granite microstructure modelling has only been used in limited studies with the mineral pattern often remaining poorly constructed. In this study, the authors developed a new approach for generating 2D and 3D granite microstructure models from a 2D image by combining a heterogeneous material reconstruction method (simulated annealing method) with Voronoi tessellation.

More specifically, the stochastic information in the 2D image is first extracted using the two-point correlation function (TPCF). Then an initial 2D or 3D Voronoi diagram with a random distribution of the minerals is generated and optimised using a simulated annealing method until the corresponding TPCF is consistent with that in the 2D image. The generated microstructure model accurately inherits the stochastic information (e.g. volume fraction and mineral pattern) from the 2D image. Lastly, the authors compared the topological characteristics and mechanical properties of the 2D and 3D reconstructed microstructure models with the model obtained by direct mapping from the 2D image of a real rock sample.

The good agreements between the mapped and reconstructed models indicate the accuracy of the reconstructed microstructure models on topological characteristics and mechanical properties.

The newly developed reconstruction method successfully transfers the mineral pattern from a granite sample into the 2D and 3D Voronoi-based microstructure models ready for use in grain-scale modelling.

Although crowdsourcing has gained significant attention and is being used by numerous companies to develop new products and solve practical issues, the performance of crowdsourcing is not optimistic. The purpose of this paper is to develop a validated risk profile of crowdsourcing and investigate the relationships among different types of risks and those between risks and performance in crowdsourcing.

Based on the quantitative data collected from 136 crowdsourcing participants in China, two dimensions (i.e. social system and technical system risks) and five sub-dimensions (i.e. crowdsourcer, relationship, crowdsourcee, complexity, and requirement) of crowdsourcing risks are developed and validated. A theoretical model that integrates crowdsourcing risks and performance is developed. The technique of partial least squares is employed to assess the measurement model and test the hypotheses.

The empirical evidence determines the positive association of social system risks with technical system risks, which in turn negatively affect crowdsourcing performance. Specifically, relationship risk is positively affected by crowdsourcer and crowdsourcee risks, and these risks positively affect requirement and complexity risks. However, requirement and complexity risks negatively affect crowdsourcing performance.

This study explores the interrelationship between various risks and the relationship between risk and performance in the context of crowdsourcing by integrating risk-based view with socio-technical theory. Systematic but different risk mitigation strategies should be designed in crowdsourcing to manage risks and enhance performance.