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This study aims to assess the use of variational quantum imaginary time evolution for solving partial differential equations using real-amplitude ansätze with full circular entangling layers. A graphical mapping technique for encoding impulse functions is also proposed.

The Smoluchowski equation, including the Derjaguin–Landau–Verwey–Overbeek potential energy, is solved to simulate colloidal deposition on a planar wall. The performance of different types of entangling layers and over-parameterization is evaluated.

Colloidal transport can be modelled adequately with variational quantum simulations. Full circular entangling layers with real-amplitude ansätze lead to higher-fidelity solutions. In most cases, the proposed graphical mapping technique requires only a single bit-flip with a parametric gate. Over-parameterization is necessary to satisfy certain physical boundary conditions, and higher-order time-stepping reduces norm errors.

Variational quantum simulation can solve partial differential equations using near-term quantum devices. The proposed graphical mapping technique could potentially aid quantum simulations for certain applications.

This study shows a concrete application of variational quantum simulation methods in solving practically relevant partial differential equations. It also provides insight into the performance of different types of entangling layers and over-parameterization. The proposed graphical mapping technique could be valuable for quantum simulation implementations. The findings contribute to the growing body of research on using variational quantum simulations for solving partial differential equations.

The purpose of this study is to investigate the inner flow field characteristics of groove textures in thrust bearings. Cavitation and vortex are studied simultaneously to enrich the theories of surface texture.

Navier–Stokes equations are solved using computational fluid dynamics. The MIXTURE model is adopted to study the gas–liquid mixture flow under the cavitation condition.

Re number, the depth ratio as well as the area ratio of the groove texture and the bottom shape are all influencing factors of the inner flow field characteristics. When cavitation region and vortex region occupy the bottom of the groove texture, these do not overlap because of the pressure gradient. The positive pressure gradient in the non-cavitation region introduces nonlinearity into the velocity profiles, which affects the load-carrying capacity and friction.

Cavitation and vortex are studied simultaneously only in this study. The characteristics of the textured thrust bearing can be analyzed and explained with the combined effect of cavitation and vortex.

The purpose of this study is to investigate wet multi-disc brake temperature field and optimal oil supply under continuous braking condition. The oil supply of wet multi-disc brake has a direct impact on the drivability and fuel economy for tracked vehicles. Too small flow will result in the higher temperature and failure of brake while excessive one will lead to slow engagement increasing disengaged torque and the transmission efficiency could decline notably. The optimal oil supply and brake temperature field were obtained in this research.

This article investigated on the heat dissipation capability and optimal oil supply of the brake by the means of CFX model. The working condition was continuous braking and the lubricating and cooling factors were included in the model.

That the complex trends with increased oil flow is inconsistent with the traditional formula in which the effects of grooves were neglected. The fitting curve of optimal oil supply can predict various needed oil flow in various rotating speed and it provides a theoretical guidance for oil supply design.

Traditional empirical formula of heat transfer coefficient and Reynolds equation solved by different methods could be difficult to deal with the complex boundary conditions of wet multi-disc brake. CFX model can solve the problem of complex boundary condition. The optimal oil supply curve can provide a theoretical guidance for oil supply design.

The purpose of this study is to theoretically discuss and empirically test the mediating effect of emotional exhaustion (EE) and the moderating effects of perceived coworker support (PCS) and positive affectivity (PA) in the relationship between abusive supervision (AS) and knowledge hiding (KH).

The authors adopted a three-wave survey to collect data from eight high-tech companies in north China. The final sample of 209 available responses was analyzed with hierarchical regression analyses and bias-corrected bootstrapping methods.

AS positively affected employees’ KH. EE fully mediated this positive relationship. PCS and PA attenuated the relationship between AS and EE, respectively, and the mediating effects of EE.

First, the study contributes to the knowledge management and leadership literature by examining the relationship between the following two dysfunctional workplace behaviors: AS and KH. Second, the authors explicitly tested the underlying psychological mechanism in the above relationship. Third, this study specified two ways – obtaining support from coworkers and generating positive emotions – to attenuate the toxic effects of AS on victims.

This article aims at investigating the global stiffness optimization of a Tricept manipulator and the multi-objective optimization of global stiffness and well-conditioned workspace for 3SPS-S manipulator. Firstly, the genetic algorithm is used to optimize the sum of mean value and the standard deviation of leading diagonal elements of the compliance matrix of the Tricept manipulator to obtain the maximum global stiffness. Secondly, the sum of mean value and standard deviation of leading diagonal elements of the compliance matrix of the 3SPS-S manipulator was used to evaluate the global stiffness and the global condition index was used to evaluate the workspace. The global stiffness and well-conditioned workspace of the 3SPS-S mechanism were optimized simultaneously based on Pareto front theory, and the results show that the stiffness and workspace have increased after optimization.

This research investigated the mechanism of wet friction plates of engagement and solved the problem that the lock-up friction coefficient of sinter material could not be obtained but from experiments for a long time. The paper aims to discuss these issues.

Including four steps: surface topology sampling and reconstruction, fractal parameters obtaining and fractal surface simulating, micro-contact mechanics model and friction coefficient fractal model, and experimental verification.

After running in stage of the friction plates, the fractal dimension would reach a dynamically stable stage for a long time. The proportional coefficient K expresses the correlation between the base hardness and the asperities shear strength. The model could be property for one or more working condition via adjusting the coefficient K. The experiment data of friction coefficient are increased as the load magnified both in the model prediction and experiment practice. The trend is different from other models.

This research is original and it is supported by national defense project. It would be served for tracked vehicles to solve the defect in transmission system. The friction coefficient is obtained via solving the tangential force in MB model. The surface topography could be reconstructed by laser topography instrument and the parameters could be received by program.

The purpose of this paper is to examine global monetary economic growth with free trade. It develops a multi‐country monetary growth model with capital accumulation to provide some insights into complexity of economic globalization with free trade and financial markets.

The real aspects of the model is based on the neoclassical growth theory and monetary aspects of the model are based on the money‐in‐utility approach. The behavior of households is based on an alternative approach. The paper shows that the dynamics of the J‐country world economy can be described by 2J‐dimensional differential equations.

This paper simulates equilibrium and motion of the global economy with three, developed, newly industrializing, and developing countries and Cobb‐Douglas production functions. As the global monetary economic system is unstable, the perfectly competitive world economy may either experience unlimited growth or economic crisis. Because of the choice of the initial conditions and the parameters, the simulation demonstrates a situation of global economic declination. This paper also demonstrates, for instance, that the global economy worsens off as the developed economy reduces its propensity to save or increases its inflation policy.

This paper also tries to provide some possible implications of our model for the recent economic crisis. A policy implication of the results is that as global economies with free trade and financial markets are possibly structurally unstable and the global economy may suffer from economic declination, government interventions, and co‐operation among countries are necessary for global sustainable development.

The paper offers insights into the linkage between national monetary policies and global economic growth.

This study aims to examine dynamic interactions among economic growth, geography and the housing market with public goods financed by the government. A general dynamic equilibrium model of an isolated economy with economic geography, local public goods and capital accumulation is to be constructed. The economy has three sectors, supplying industrial goods, housing, and local public goods. The model synthesizes the main ideas in neoclassical growth theory, the Alonso urban model, and the Muth housing model in an alternative framework to the traditional growth theory.

The model is based on the neoclassical growth theory with an alternative approach to household behavior. The paper shows how to solve the dynamics of the economic system and simulate the model to demonstrate dynamic interactions among economic growth, housing market, residential distribution and public goods over time and space.

The paper simulates equilibrium and motion of the spatial economy with Cobb‐Douglas production and utility functions. The simulation demonstrates, for example, that, as the tax rate on the land income is increased, the total capital stocks and the stocks employed by the three sectors are increased, the rate of interest falls and the output of the industrial sector and the wage rate are increased, the land devoted to local public goods falls and the land rent and housing rent rise over space, the consumption level of the industrial goods and the total expenditures on the public goods are increased.

The paper provides some possible implications of the model for complicated consequences of government policy over time and space. In particular, the paper shows that a change in government policy not only has a macroeconomic impact over time, but also affects the economic geography of the national economy.

The paper offers insights into the linkage among growth, national public policies and economic geography.

Laser cladding deposition is limited in industrial application by the micro-defects and residual tensile stress for the thermal forming process, leading to lower fatigue strength compared with that of the forging. The purpose of this paper is to develop an approach to reduce stress and defects.

A hybrid process of laser cladding deposition and shot peening is presented to transform surface strengthening technology to the overall strengthening technology through layer-by-layer forming and achieve enhancement.

The results show that the surface stress of the sample formed by the hybrid process changed from tensile stress to compressive stress, and the surface compressive stress introduced could reach more than four times the surface tensile stress of the laser cladding sample. At the same time, internal micro-defects such as pores were reduced. The porosity of the sample formed by the hybrid process was reduced by 90.12% than that of the laser cladding sample, and the surface roughness was reduced by 43.16%.

The authors believe that the hybrid process proposed in this paper can significantly expand the potential application of laser cladding deposition by solving its limitations, promoting its efficiency and applicability in practical cases.