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The purpose of this paper is to study the breather waves, rogue waves and solitary waves of an extended (3 + 1)-dimensional Kadomtsev–Petviashvili (KP) equation, which can be used to depict many nonlinear phenomena in fluid dynamics and plasma physics.

The authors apply the Bell’s polynomial approach, the homoclinic test technique and Hirota’s bilinear method to find the breather waves, rogue waves and solitary waves of the extended (3 + 1)-dimensional KP equation.

The results imply that the extended (3 + 1)-dimensional KP equation has breather wave, rogue wave and solitary wave solutions. Meanwhile, the authors provide the graphical analysis of such solutions to better understand their dynamical behavior.

These results may help us to further study the local structure and the interaction of solutions in KP-type equations. The authors hope that the results provided in this work can help enrich the dynamic behavior of such equations.

The purpose of this study is to examine the lump solutions of the (3 + 1)-dimensional nonlinear evolution equations by considering a (3 + 1)-dimensional generalized Kadomtsev–Petviashvili (gKP) equation and a (3 + 1)-dimensional variable-coefficient generalized B-type Kadomtsev–Petviashvili (vcgBKP) equation as examples.

Based on Hirota’s bilinear theory, a direct method is used to examine the lump solutions of these two equations.

The complete non-elastic interaction solutions between a lump and a stripe are also discussed for the equations, which show that the lump solitons are swallowed by the stripe solitons.

The dynamics of these solutions are analyzed to enrich the diversity of the dynamics of high-dimensional KP-type nonlinear wave equations.

The purpose of this paper is to find homoclinic breather waves, rogue waves and soliton waves for a (3 + 1)-dimensional generalized Kadomtsev–Petviashvili (gKP) equation, which can be used to describe the propagation of weakly nonlinear dispersive long waves on the surface of a fluid.

The authors apply the extended Bell polynomial approach, Hirota’s bilinear method and the homoclinic test technique to find the rogue waves, homoclinic breather waves and soliton waves of the (3 + 1)-dimensional gKP equation.

The results imply that the gKP equation admits rogue waves, homoclinic breather waves and soliton waves. Moreover, the authors also find that rogue waves can come from the extreme behavior of the breather solitary wave. The authors analyze the propagation and interaction properties of these solutions to better understand the dynamic behavior of these solutions.

These results may help us to further study the local structure and the interaction of waves in KP-type equations. It is hoped that the results can help enrich the dynamic behavior of such equations.

The purpose of this study is to produce families of exact soliton solutions (2+1)-dimensional Korteweg-de Vries (KdV) equation, that describes shallow water waves, using an ansätze approach.

This article aims to introduce a recently developed ansätze for creating soliton and travelling wave solutions to nonlinear nonintegrable partial differential equations, especially those with physical significance.

A recently developed ansätze solution was used to successfully construct soliton solutions to the (2 + 1)-dimensional KdV equation. This straightforward method is an alternative to the Painleve test analysis, yielding similar results. The strategy demonstrated the existence of a single soliton solution, also known as a localized wave or bright soliton, as well as singular solutions or kink solitons.

The ansätze solution used to construct soliton solutions to the (2 + 1)-dimensional KdV equation is novel. New soliton solutions were also obtained.

This paper aims to numerically study the compositional flow of two- and three-phase fluids in one-dimensional porous media and to make a comparison between several upwind and central numerical schemes.

Implicit pressure explicit composition (IMPEC) procedure is used for discretization of governing equations. The pressure equation is solved implicitly, whereas the mass conservation equations are solved explicitly using different upwind (UPW) and central (CEN) numerical schemes. These include classical upwind (UPW-CLS), flux-based decomposition upwind (UPW-FLX), variable-based decomposition upwind (UPW-VAR), Roe’s upwind (UPW-ROE), local Lax–Friedrichs (CEN-LLF), dominant wave (CEN-DW), Harten–Lax–van Leer (HLL) and newly proposed modified dominant wave (CEN-MDW) schemes. To achieve higher resolution, high-order data generated by either monotone upstream-centered schemes for conservation laws (MUSCL) or weighted essentially non-oscillatory (WENO) reconstructions are used.

It was found that the new CEN-MDW scheme can accurately solve multiphase compositional flow equations. This scheme uses most of the information in flux function while it has a moderate computational cost as a consequence of using simple algebraic formula for the wave speed approximation. Moreover, numerically calculated wave structure is shown to be used as a tool for a priori estimation of problematic regions, i.e. degenerate, umbilic and elliptic points, which require applying correction procedures to produce physically acceptable (entropy) solutions.

This paper is concerned with one-dimensional study of compositional two- and three-phase flows in porous media. Temperature is assumed constant and the physical model accounts for miscibility and compressibility of fluids, whereas gravity and capillary effects are neglected.

The proposed numerical scheme can be efficiently used for solving two- and three-phase compositional flows in porous media with a low computational cost which is especially useful when the number of chemical species increases.

A new central scheme is proposed that leads to improved accuracy and computational efficiency. Moreover, to the best of authors knowledge, this is the first time that the wave structure of compositional model is investigated numerically to determine the problematic situations during numerical solution and adopt appropriate correction techniques.

Educated elites are making their mark on the stratification structure of the metropolitan US. Educated elites are proportionally greater whenever the economy is service dominated, and furthermore, these elites are the key factor in explaining why disparities resulting from high earners are present in service dominated areas. The resulting inequality in earnings is one of the unanticipated consequences of the growth of an educated elite, at least among males. It remains to be seen whether female elites will resemble males in their influence on inequality if sex differences in earnings disappear. The elite is a professional cadre rather than an aristocracy based solely on inherited wealth, placed just beyond an upper middle class. Given their background, education, affluence and numbers, the choices this elite makes on issues will influence the course of society.

This study aims to explore how team task-related social media usage (TSMU) and social-related social media usage (SSMU) affect employees' perceptions of intra-team cooperation and competition and further individual creativity.

This study conducted a questionnaire survey on enterprises in China that have implemented social media and obtained 348 useable questionnaires from 55 work teams.

The results revealed that employees' perceptions of intra-team cooperation and competition can promote employees' creativity. Employees' cooperation perception can be significantly positively affected by TSMU and SSMU, whereas employees' competition perception can be significantly positively affected by TSMU. Regarding congruence, the results indicated that the more balanced between TSMU and SSMU, the stronger the competition perception.

Managers should pay critical attention to the role of team social media usage (SMU) in shaping employees' perceptions of their team environments. They should realize the different outcomes and the joint effects of the different types of SMU.

This study contributes to the social media literature by explaining the impact of team SMU on employees' perceptions and evaluations of team environments based on the social information processing theory. The study presents the relationships among team SMU, employees' perceptions of cooperation and competition and employee creativity. Moreover, this study expands research on the trade-off of SMU by exploring the impact of balanced and imbalanced SMU in a work team.

The speed of computing and other automated processes plays an important role in how the world functions by causing “time compression”. This paper aims to review reasons to believe computation will continue to become faster in the future, the economic consequences of speedups and how these affect risk, ethics and governance.

A brief review of science and trends followed by an analysis of consequences.

Current computation is far from the physical limits in terms of processing speed. Algorithmic improvements may be equally powerful but cannot easily be predicted or bounded. Communication and sensing is already at the physical speed limits, although improvements in bandwidth will likely be significant. The value in these speedups lies in productivity gains, timeliness, early arrival of results and cybernetic feedback shifts. However, time compression can lead to loss of control owing to inability to track fast change, emergent or systemic risk and asynchrony. Speedups can also exacerbate inequalities between different agents and reduce safety if there are competitive pressures. Fast decisions are potentially not better decisions, as they may be made on little data.

The impact on society and the challenge to governance are likely to be profound, requiring adapting new methods for managing fast-moving and technological risks.

The speed with which events happen is an important aspect of foresight, not just as a subject of prediction or analysis, but also as a driver of the kinds of dynamics that are possible.

Coproduction, as one component of cocreation of value, offers many benefits to customers and management, but also requires customers to invest a considerable amount of effort and time. The purpose of this paper is to investigate the coproduction paradox of benefits and costs.

One experimental study and two cross-sectional field studies across three service industries test the nonlinear relationship between level of coproduction and customer loyalty.

Results show not only the optimum level but also the negative effects of increasing levels of coproduction on customer loyalty and, in turn, monetary expenditures. The negative effect can be partially offset by perceived process enjoyment (PE), such that consumers who enjoy the process exhibit increased loyalty after the optimum coproduction point. Customer self-efficacy (SE), however, further strengthens the inverted u-shaped relationship.

Further research should try to replicate the findings in more complex and less hedonic service settings (e.g. financial investments) because both PE and SE might be even more powerful here.

Service managers need to determine the optimal degree to which customers want to engage in the creation of services and avoid overburdening them. Management should further explore opportunities to elicit feelings of fun and enjoyment through coproduction.

Research usually highlights the potential benefits of coproduction for customers and companies and suggests a positive linear relationship between coproduction and success outcomes. This article instead shows that after an optimum level, the marginal benefits of coproduction for customer loyalty turn negative.

The present contribution is in the field of quantum modelling of macroscopic phenomena. The focus is on one enigmatic aspect of quantum physics, namely, the Einstein–Podolsky–Rosen paradox and entanglement. After a review of the state-of-the-art concerning macroscopic quantum effects and quantum interaction, this paper aims to propose a link between embryology and acupuncture in the framework of macroscopic intricate states induced by quantum mechanics.

The author uses the fractaquantum hypothesis which supposes that the quantum framework is applicable to all insecable elements in nature, whatever their size.

This contribution considers an open question related to a possible link between acupuncture and embryology: can a weak form of intrication be maintained during stem cell division to interpret the acupuncture meridians as an explicit manifestation of a macroscopic intricate system? The macroscopic structure suggested by quantum mechanics could be a beginning of explanation of acupuncture through the embryologic development.

A fundamental hypothesis is the fact that during cell division, cells keep some weak intrication.

This contribution suggests a structure of the acupuncture meridians. The links between the acupuncture points have to be searched in the embryologic development of the individual through a weak remaing intrication of some of his cells and not in present explicit relations.

A new link between occidental and oriental cultures is explored.

This contribution suggests conceptual links between acupuncture, embryology and macroscopic intricate states.