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The purpose of this paper is to find solutions for the (2+1)-dimensional B-type Kadomtsev-Petviashvili equation and to research the quality of B-type Kadomtsev-Petviashvili equation.

The authors apply the extended three-wave approach and the homoclinic test technique to solve the B-type Kadomtsev-Petviashvili equation.

The authors obtain breather type of cross-kink solutions, doubly breather type of kink solitary solutions and the breather type of kink wave solutions for B-type Kadomtsev-Petviashvili equation.

As nonlinear evolution equations are characterized by rich dynamical behaviors, the authors have just found some of them and others are still to be found.

These results may help us to investigate the local structure and the interaction of waves in high-dimensional models.

The purpose of this paper is to reveal dynamical behavior of nonlinear wave by searching for the new breather soliton and cross two-soliton solutions of the fifth-order Caudrey-Dodd-Gibbon (CDG) equation.

The authors apply bilinear form and extended homoclinic test approach to the fifth-order CDG equation.

In this paper, by using bilinear form and extended homoclinic test approach, the authors obtain new breather soliton and cross two-soliton solutions of the fifth-order CDG equation. It is shown that the extended homoclinic test approach, with the help of symbolic computation, provides an effective and powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

The research manifests that the structures of the solution to nonlinear equations are diversified and complicated.

The methods used in this paper can be widely applied to the research of spatial and temporal characteristics of nonlinear equations in physics and engineering technology. These methods are also conducive for people to know objective laws and grasp the essential features of the development of the world.

The purpose of this paper is to reveal the dynamical behavior of higher dimensional nonlinear wave by searching for the multi-wave solutions to the (3+1)-D Jimbo-Miwa equation.

The authors apply bilinear form and extended homoclinic test approach to the (3+1)-D Jimbo-Miwa equation.

In this paper, by using bilinear form and extended homoclinic test approach, the authors obtain new cross-kink multi-soliton solutions of the (3+1)-dimensional Jimbo-Miwa equation, including the periodic breathertype of kink three-soliton solutions, the cross-kink four-soliton solutions, the doubly periodic breather-type of soliton solutions and the doubly periodic breather-type of cross-kink two-soliton solutions. It is shown that the extended homoclinic test approach, with the help of symbolic computation, provides an effective and powerful mathematical tool for solving higher dimensional nonlinear evolution equations in mathematical physics.

The research manifests that the structures of the solution to higher dimensional nonlinear equations are diversified and complicated.

The methods used in this paper can be widely applied to the research of spatial and temporal characteristics of nonlinear equations in physics and engineering technology. These methods are also conducive for people to know objective laws and grasp the essential features of the development of the world.

With continuous concerning on the toxic of element Pb, Pb-free solder was gradually used to replace traditional Sn-Pb solder. However, during the transition period from Sn-Pb to Pb-free solder, mixing of Sn-Pb and Pb-free is inevitable occurred in certain products, and in China where Sn-Pb solder was still used extensively in certain areas especially. Correspondingly, understanding reliability of Sn-Pb solder joints was very important, and further studies were needed.

Thermal shock test between −55°C and 125 °C was conducted on Sn-37Pb solder bumps in the BGA package to investigate the microstructure evolution and the growth mechanism of interfacial intermetallic compound (IMC) layer. The effects of thermal shock on the mechanical property and fracture behavior of Sn-37Pb solder bumps were discussed.

Pb-rich phase was coarsened and voids were increased at first; Pb-rich phase was refined and voids were decreased secondly with the increase of thermal shock cycles; the shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67MPa at 2,000 cycles; interfacial IMCs of solder bumps was from typical scallop-type into smooth, the composition of IMCs was from Cu₆Sn₅ into Cu₆Sn₅ and Cu₃S_n after thermal shock with 1,500 and 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure respectively.

Compared with the board level test method, the impact shear test for the single solder bump is more convenient and economical and is actively pursued by the industries. The shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67 MPa at 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure.

This paper presents the application of grey modeling for thermal spray processing parameter analysis in less data environment.

Based on processing knowledge, key processing parameters of thermal spray process are analyzed and preselected. Then, linear and non-linear grey modeling models are integrated to mine the relationships between different processing parameters.

Model A reveals the linear correlation between the HVOF process parameters and the characterization of particle in-flight with average relative errors of 9.230 percent and 5.483 percent for velocity and temperature.

The prediction accuracies of coatings properties vary, which means that there exists more complex non-linear relationship between the identified input parameters and coating results, or more unexpected factors (e.g. factors from material side) should be further investigated.

According to the modeling case in this paper, method has potential to deal with other diverse modeling problems in different industrial applications where challenge to collecting large quantity of data sets exists.

It is the first time to apply grey modeling for thermal spray processing where complicated relationships among processing parameters exist. The modeling results show reasonable results to experiment and existing processing knowledge.

After some years in which industrial policy was frowned upon, it is now widely considered to be a legitimate arena for policy formulation. The danger is that policymakers will seek to return to previously implemented policies. However many elements of this historic policy agenda are not replicable because of changes in global governance regulations. But changing framing conditions in the global economy also mean that the historic agenda is no longer optimal.

This chapter discusses four disruptive structural changes which affect the industrial policy agenda – the changing manufactures-commodities terms of trade, the centrality of global value chains in world industrial production, the growth of environmental externalities which affect growth and development, and the need to develop more inclusive patterns of growth.

The key findings are that there is scope for industrial policies to successfully confront these challenges, but that this will be contextual and may require a mix of policies designed to meet multiple objectives.

Significantly, industrial policy should be seen as a process aligning the operations of key stakeholders and subject to change as conditions alter, rather than as an industrial policy roadmap of the sort which frequently characterised policy in the past.

The purpose of this study is to address the issue that the traditional V-shaped ball valve profile shape is limiting the flow control characteristics in a series structure and to optimize the design profile by proposing an open-hole profile.

This paper proposes a Gaussian process regression surrogate model based on the genetic algorithm optimization of swarm intelligence, combined with the Expected Improvement point addition criterion, to optimize and correct the design profile. The flow regulation performance of the optimized V-shaped regulating ball valve is verified through a combination of numerical simulation and experiment.

The results demonstrate that the optimized V-shaped regulating ball valve has higher flow regulation accuracy and a more stable flow regulation process. After optimization, the flow characteristic curve of the spool is closer to the ideal equal percentage characteristic. The simulation results of the flow field are consistent with the experimental results.

The proposed method significantly reduces the optimization time, has higher efficiency and solves the problem that traditional optimization methods struggle with, which is ensuring optimal flow regulation performance. Compared to the traditional trial-and-error optimization method, the proposed method is more effective. The feasibility of the method is supported by experimental results.

In the field of global leadership, much of the research has focused on uncovering competencies and methods for assessing competencies. The process of developing global leaders has been researched less frequently; however, it is widely accepted that this process involves learning on the part of the leader. Mezirow’s (1978, 1991) transformative learning is a special type of learning in the domain of adult education and a useful lens to better understand the disorienting triggers that are thought to induce global leadership development (GLD). In simple terms, a disorienting experience occurs when we discover that something we thought was certain is now uncertain. Conducting business in another country or merely navigating to a grocery store or restaurant there can be a disorienting experience. In these situations, people are exposed to new information that does not fit their current meaning structures or thought paradigms, and at this juncture, people have a choice: to transform their perspective or remain unchanged. When individuals transform their perspective, they are experiencing transformative learning. The first section of this chapter reviews the concept of disorienting experiences across disciplines and within the domain of learning and education. The second section explains three GLD process models with a special focus on the role played by disorienting trigger events in each one. The final section explains the Disorientation Index (Ensign, 2019), which articulates dimensions of trigger events. The chapter concludes with future research directions and practical implications.

This study aims to identify and analyse the gains and strains associated with flexible working practices (FWPs) introduced and adopted prior to and during the pandemic and consider how these experiences are likely to shape the future of workplace flexibility post-pandemic.

A case study research strategy was adopted to explore the FWPs implemented by a state-owned organisation in the Chinese publishing industry. A mixed data collection method was used. Quantitative data was collected from 50 valid questionnaires, which was followed by 7 qualitative interviews to gain rich insights into the availability and effectiveness of various FWPs and associated benefits and drawbacks.

While the results confirm positive effects FWPs have on employee engagement and retention and on business continuity and employee well-being during the pandemic, the empirical analysis highlights the performance-driven patterns in use and impacts of some FWPs, which caused concerns and dilemmas. Besides the increasing intense market competition, the changing face of state-owned enterprises and managerial attitudes have been found to have significant effects on the use of FWPs.

This paper has contributed to a better understanding of flexible working in an under-researched setting, reflected in changes before and during the pandemic, offering an insight into the commercialised nature of flexible working in the Chinese context. It has implications for organisations and HR practitioners as they envision future workplace flexibility.

This study explored whether the critical incident management systems (CIMS) model can predict the EMS performance in the COVID-19 context. Past research has established the significance of early detection and response (ER) in the context of Ebola virus disease (EVD), prompting a question of whether the model can also be helpful in the COVID-19 context. Consequently, the authors assessed whether ER influences the impact of communication capacity (CC), reliable information channel (RC) and environment (EN) on COVID-19 EMS performance. Assessing these relationships will advance emerging infectious disease (EID) preparedness.

The authors employed standardized measurement instruments of the CIMS model (CC, ER, RC and EN) to predict the performance of COVID-19 EMS using structural equation modeling (SEM) in a study of 313 participants from frontline responders.

The results show that the relationship of ER and EN with COVID-19 EMS performance is positive, while that of EN on CC is negative. The relationship between EN and COVID-19 EMS performance was insignificant. Contrary to the hypothesis, CC was negatively significant to COVID-19 EMS performance due to poor communication capacities.

The authors acknowledge some limitations due to challenges faced in this study. First, Data collection was a significant limitation as these questionnaires were built and distributed in June 2020, but the response time was prolonged due to the recurring nature of the pandemic. The authors had wanted to implore the inputs of all stakeholders, and efforts were made to reach out to various Ministry of Health, the local CDC and related agencies in the region via repeated emails explaining the purpose of the study to no avail. The study finally used the frontline workers as the respondents. The authors used international students from various countries as the representatives to reach out to their countries' frontline workers. Second, since the study was only partially supported using the CIMS model, future studies may combine the CIMS model with other models or theories. Subsequent research reassesses this outcome in other contexts or regions. Consequently, further research can explore how CC can be improved with COVID-19 and another future EID in the region. This may improve the COVID-19 EMS performance, thereby expanding the lesson learned from the pandemic and sustaining public health EID response. Additionally, other authors may combine the CIMS model with other emergency management models or theories to establish a fully supported theoretical model in the context of COVID-19.

The findings have practical implications for incident managers, local CDCs, governments, international organizations and scholars. The outcome of the study might inform these stakeholders on future direction and contribution to EID preparedness. This study unfolds the impact of lessons learned in the region demonstrated by moderating early detection and responses with other constructs to achieve COVID-19 EMS performance. The findings reveal that countries that experienced the 2013–2016 Ebola outbreak, were not necessarily more prepared for an epidemic or pandemic, judging by the negative moderating impact of early detection and response. However, these experiences provide a foundation for the fight against COVID-19. There is a need for localized plans tailored to each country's situation, resources, culture and lifestyle. The localized plan will be to mitigate and prevent an unsustainable EID management system, post-epidemic fund withdrawals and governance. This plan might be more adaptable and sustainable for the local health system when international interventions are withdrawn after an epidemic. Public health EID plans must be adapted to each country's unique situation to ensure sustainability and constantly improve EID management of epidemics and pandemics in emergency response. The high to moderate importation risk in African countries shows Africa's largest window of vulnerability to be West Africa (Gilbert et al., 2020). Therefore, they should be in the spotlight for heightened assistance towards the preparedness and response for a future pandemic like COVID-19. The West African region has a low capacity to manage the health emergency to match the population capacities. The COVID-19 outbreak in West Africa undoubtedly inflicted many disruptions in most countries' economic, social and environmental circumstances. The region's unique challenges observed in this study with CC and reliable information channels as being negatively significant highlight the poor maintenance culture and weak institutions due to brain drain and inadequate training and monitoring. This outcome practically informs West African stakeholders and governments on aspects to indulge when trying to improve emergency preparedness as the outcomes from other regions might not be applicable.

This study explored the relevance of the CIMS model in the context of the COVID-19 pandemic, revealing different patterns of influence on COVID-19 EMS performance. In contrast to the extant literature on EVD, the authors found the moderating effects of ER in the COVID-19 context. Thus, the authors contribute to the COVID-19 EMS performance domain by developing a context-driven EMS model. The authors discuss the theoretical and practical implications.