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This paper quantifies the way in which the Regional Comprehensive Economic Partnership (RCEP) affects the restructuring of global value chains (GVCs). It incorporates an input– output structure into a general equilibrium model, highlighting important differences between intermediates and final goods. Using tariff reduction schedules for the RCEP agreement and Asian Development Bank Multi‐Region Input–Output database, it evaluates the impact of the RCEP's tariff cuts on vertical specialization and the GVC position index of members. It shows that the RCEP significantly increased vertical specialization and the weighted average number of stages for members for primary factors of production and final consumption, which led to more complex and longer production chains. This was mainly due to the trade creation in intermediates imported from member countries and those outside it. This is an important finding, distinct from traditional trade models without an input–output structure. [ABSTRACT FROM AUTHOR]

Reinsurers possess high volumes of policy listings data from insurers, which they use to provide insurers with analytical insights and modeling that guide reinsurance treaties. These insurers often act on the same data for their own internal modeling and analytics needs. The problem is this data is messy and needs significant preparation in order to extract meaningful insights. Traditionally, this has required intensive manual labor from actuaries. However, a host of modern AI techniques and ML system architectures introduced in the past decade can be applied to the problem of insurance data preparation. In this paper, we explore a novel application of AI/ML on policy listings data that poses its own unique challenges, by outlining the holistic AI-based platform we developed, ECLIPSE (Elegant Cleaning and Labeling of Insurance Policies while Standardizing Entities). With ECLIPSE, actuaries not only save time on data preparation but can build more effective loss models and provide crisper insights. [ABSTRACT FROM AUTHOR]

A novel numerical method to optimise the shape of the contact surfaces in complex engineering components is developed herein. The arbitrary Lagrangian–Eulerian method is applied to adjust the node coordinates of the contact surface in the finite element model by the user subroutine UMESHMOTION in ABAQUS®. The adjustment strategy changes the profile of the contact surface gradually according to the local contact pressure and a termination criterion based on the coefficient of variation controls the optimisation process. Thus, a new profile is obtained through continuous modification from the former iteration until the termination condition is satisfied. A performance test case using a 3D drum-brake was used to demonstrate this method, and the new shape of the friction plates was obtained to yield a better contact status. The results demonstrate that this method can improve the contact status and provide a good reference for new designs. [ABSTRACT FROM AUTHOR]

This paper explores the contribution of domestic and foreign demand to China's income growth by business function. To this end, we extend a single country input–output approach to a global multi-country setting, and further redefine the measure via forward linkages. We also propose chaining structural decomposition analysis to identify the role of domestic and foreign demand in functional income changes over 1999–2011. Using the World Input–Output Database combined with Labor Occupations Database, we distinguish functional activities in production, management, marketing and R&D. This enables us to find that domestic and foreign final demands, especially the former, jointly lead to China's income growth by business function. Dynamically, the generally upward trends in China's income hold in the aggregate as well as by industry and business function. We also find that China's income growth is quite heterogeneous across industries and business functions. [ABSTRACT FROM AUTHOR]

Because misalignments derived from the deflections of transmission systems have significant effects on the load capacity of planetary gears, these misalignments should be accurately considered in the analysis of planetary gears. Here, we develop a new approach for misalignment calculations of cylindrical planetary gears. A nonlinear model of a planetary gear transmission system is built based on the finite element method and nonlinear bearing theory for misalignment calculations that can precisely simulate the structural characteristics and mechanical properties of a planetary gear system. The nonlinear static equation of a planetary system is solved efficiently using the Newton–Raphson method. Gear misalignments of all the planet branches are determined by the results of the system static analysis. The reliability and advantages of the proposed method are discussed via case studies. The effects of including the variation of the planet positions and the nonlinearity of the bearing stiffness on the planetary gear misalignments under different load conditions are studied. The misalignments can be reliably determined using the proposed method for calculating the load capacity of planetary gears. [ABSTRACT FROM AUTHOR]

Transmission efficiency is the main concern in the design of lubrication systems for gear transmission systems, such as the vehicle axle. This paper presents an optimization method to reduce the churning loss and improve the transmission efficiency in an axle based on computational fluid dynamics and the response surface method. A simplified model was applied to determine the optimal solutions to reduce the churning loss of the wheel. The response surface models were constructed based on the numerical and orthogonal experiments to approximate the relationship between the related structures and the churning loss. A multi-objective optimization model was developed to reduce the churning loss at speeds of 50 and 90 km/h. The multi-objective optimization method of non-dominated sorting genetic algorithm-II was applied to determine the Pareto front of the optimal solutions for the churning loss. A comparative experiment was conducted to validate the optimal effect. The measurements indicate the churning loss in the optimal axle was 10.4–12.3% lower than that in the original axle, and the oil temperature in the optimal axle was approximately 2.1°C lower than that of the original axle. [ABSTRACT FROM AUTHOR]

Transmission efficiency is the main concern in the design of the lubrication system for a gear transmission system, such as a vehicle axle. This paper presents an optimization method to reduce the churning loss and improve the transmission efficiency in an axle based on the computational fluid dynamics and the response surface method. In this study, the computational fluid dynamics method was applied to simulate the lubrication flow in the axle housing. A numerical model was built for the splash lubrication system that included the entire structure of the hypoid gears, bearings, oil passage, and other parts. The numerical results provided direct visualization of the oil flow inside the axle housing, and the numerical predictions for the oil distribution and churning loss were determined from the numerical result. Furthermore, the influences of the speed, oil level, and oil temperature on the churning loss were investigated. The oil distribution results from the numerical calculations were consistent with the experimental observations, and the error in the predictions for the churning loss was less than 9.3%. The results of this study provide a foundation for subsequent optimization work on the lubrication system of a vehicle axle. [ABSTRACT FROM AUTHOR]

The drive axle is the core of the powertrain in automotive vehicles, and numerical simulation is a common and effective approach for designing and analysing drive axles. This article develops a new numerical simulation method for drive axles considering the nonlinear couplings between gears and bearings. Two types of models are proposed and integrated: a reduced model with nonlinear bearing elements and equivalent gear elements, which is efficient for nonlinear bearing simulation, and a gear contact analysis model with equivalent bearing stiffnesses, which can accurately reflect the gear mesh conditions and system deflection. The equivalent gear mesh parameters used in the reduced model are derived from the contact analysis model, and the linear equivalent bearing stiffness matrices used in the contact analysis model are derived from the reduced model. Therefore, the static equilibrium condition of the entire drive axle system is obtained through an iterative calculation process involving the two models under the same load condition. The good correlation between the numerical and experimental results of the gear-loaded contact pattern indicates that the proposed method is reliable. [ABSTRACT FROM AUTHOR]

This article proposes a method called the cooperative coevolutionary genetic algorithm with independent ground structures (CCGA-IGS) for the simultaneous topology and sizing optimization of discrete structures. An IGS strategy is proposed to enhance the flexibility of the optimization by offering two separate design spaces and to improve the efficiency of the algorithm by reducing the search space. The CCGA is introduced to divide a complex problem into two smaller subspaces: the topological and sizing variables are assigned into two subpopulations which evolve in isolation but collaborate in fitness evaluations. Five different methods were implemented on 2D and 3D numeric examples to test the performance of the algorithms. The results demonstrate that the performance of the algorithms is improved in terms of accuracy and convergence speed with the IGS strategy, and the CCGA converges faster than the traditional GA without loss of accuracy. [ABSTRACT FROM PUBLISHER]