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The purpose of this study is to design numerical simulations of bubbly flow around a cylinder to better understand the characteristics of flow around a rigid obstacle.

The bubbly flow around a circular cylinder was numerically simulated using a semi-Lagrangian–Lagrangian method composed of a vortex-in-cell method for the liquid phase and a Lagrangian description of the gas phase. Additionally, a penalization method was applied to account for the cylinder inside the flow. The slip condition of the bubbles on the cylinder’s surface was enforced, and the outflow conditions were applied to the liquid flow at the far field.

The simulation clarified the characteristics of a bubbly flow around a circular cylinder. The bubbles were shown to move around and separate from both sides of the cylinder, because of entrainment by the liquid shear layers. Once the bubbly flow fully developed, the bubbles distributed into groups and were dispersed downstream of the cylinder. A three-dimensional vortex structure of various scales was also shown to form downstream, whereas a quasi-stable two-dimensional vortex structure was observed upstream. Overall, the proposed method captured the characteristics of a bubbly flow around a cylinder well.

A semi-Lagrangian–Lagrangian approach was applied to simulate a bubbly flow around a circular cylinder. The simulations provided the detail features of these flow phenomena.

This paper aims to provide discussions of a numerical method for bubbly flows and the interaction between a vortex ring and a bubble plume.

Small bubbles are released into quiescent water from a cylinder tip. They rise under the buoyant force, forming a plume. A vortex ring is launched vertically upward into the bubble plume. The interactions between the vortex ring and the bubble plume are numerically simulated using a semi-Lagrangian–Lagrangian approach composed of a vortex-in-cell method for the fluid phase and a Lagrangian description of the gas phase.

A vortex ring can transport the bubbles surrounding it over a distance significantly depending on the correlative initial position between the bubbles and the core center. The motion of some bubbles is nearly periodic and gradually extinguishes with time. These bubble trajectories are similar to two-dimensional-helix shapes. The vortex is fragmented into multiple regions with high values of Q, the second invariant of velocity gradient tensor, settling at these regional centers. The entrained bubbles excite a growth rate of the vortex ring's azimuthal instability with a formation of the second- and third-harmonic oscillations of modes of 16 and 24, respectively.

A semi-Lagrangian–Lagrangian approach is applied to simulate the interactions between a vortex ring and a bubble plume. The simulations provide the detail features of the interactions.

This study aims to provide discussions of the numerical method and the bubbly flow characteristics of an annular bubble plume.

The bubbles, released from the annulus located at the bottom of the domain, rise owing to buoyant force. These released bubbles have diameters of 0.15–0.25 mm and satisfy the bubble flow rate of 4.1 mm³/s. The evolution of the three-dimensional annular bubble plume is numerically simulated using the semi-Lagrangian–Lagrangian (semi-L–L) approach. The approach is composed of a vortex-in-cell method for the liquid phase and a Lagrangian description of the gas phase.

First, a new phenomenon of fluid dynamics was discovered. The bubbly flow enters a transition state with the meandering motion of the bubble plume after the early stable stage. A vortex structure in the form of vortex rings is formed because of the inhomogeneous bubble distribution and the fluid-surface effects. The vortex structure of the flow deforms as three-dimensionality appears in the flow before the flow fully develops. Second, the superior abilities of the semi-L–L approach to analyze the vortex structure of the flow and supply physical details of bubble dynamics were demonstrated in this investigation.

The semi-L–L approach is applied to the simulation of the gas–liquid two-phase flows.

One Commune One Product (OCOP) program, a rural economic development program in Vietnam, aims to empower local communities for sustainable social and economic welfare development, protect the environment and preserve tradition. This study aims to employ this program associated with tourism to support small family businesses in rural areas cost-effectively.

This study used the geographic location mapping method to design tourist routes that connect tourism resources with OCOP producers. A stakeholder approach was employed to identify suggested practical works that need to be implemented while developing this tourism initiative.

Four rural districts of Bac Giang Province, a northern province in Vietnam known as the place of various indigenous people live and traditional craft villages. Many cultural and historical tourist sites have been chosen as sample areas for this study. By using Google map, based on the Bac Giang Tourist Map and a list of recognized OCOP products in Bac Giang Province, main tourist sites (16 locations) and small family businesses (known as cooperatives and households) that have OCOP products (17 places) in the four districts have been identified. Four notable tourist routes have been formed to propose four thematic tours (two 1-day tours and two 2 days-1 night homestay tours). Suggestions for related stakeholders to ensure the sustainability of this initiative are provided.

This study is supposed to be a model of promoting small family businesses through OCOP programs and tourism activities in a sustainable way in Vietnam. The outcome of this study is in line with the stakeholder theory emphasizing the systematic connection of various stakeholders such as employees, suppliers, local communities, government agencies and others towards complex business sustainability. The results of the study cannot conclude the small family businesses in Vietnam because it adopts geographic location mapping alone. Moreover, this study focused on OCOP programs only. Future research can use other methods of primary data collection, especially from tourists' perspectives. Data triangulation can be done to explore and verify the tourist routes that have been formed according to the four thematic tours proposed. Future research could also compare hotels managed by family businesses with non-family businesses.

This study is supposed to be a model of promoting small family businesses through OCOP programs and tourism activities in a sustainable way in Vietnam.

The purpose of this study is to review the role of knowledge-sharing and its association with the Theory of Planned Behavior (TPB). TPB is the most used theory in understanding knowledge-sharing behavior in many contexts.

Based on the bibliometric approach, this study extracted and analyzed 229 journal articles on the Web of Science. In addition, two analyses (bibliographic coupling and co-word) were performed to provide science mapping in presenting the knowledge structure on the present and future research direction on knowledge-sharing and TPB.

The findings of this study suggest that two stand-out clusters are determinants and antecedents of knowledge-sharing behavior based on TPB and the role of the virtual platform and social media in facilitating knowledge-sharing among users.

This study will benefit researchers and scholars in studying individual behavioral traits underpinning TPB in achieving organizational excellence.

This study extends the findings of the previous review because of their limitations on methods. This study confirms the determinants of knowledge-sharing intention and behavior. However, this study suggests integrating TPB with other theories to provide more insights into knowledge-sharing behavior and use online and technology-based platforms to facilitate knowledge-sharing behavior.

Coronavirus disease 2019 (COVID-19) has seriously affected the global economy. How agribusinessmen are overcoming this crisis is being noticed in emerging markets. Using social capital to diversify agribusiness for getting more customers is a useful solution for the growth of agribusiness. However, there is a lack of evidence on the aggregate measurement scale of social capital and the influence of behavioral goals on the intention toward agribusiness diversification. Therefore, this study aims to develop an integrated measurement of social capital and investigate its effect on agribusiness diversification intention using the expanded theory of planned behavior (TPB).

A mixed-methods approach is used, including four in-depth interviews, three focus group discussions and two surveys. Structural equation modeling is applied to a sample of 484 respondents to test the proposed hypotheses.

The study shows the role of social capital in influencing the intention to diversify agribusiness under the premises of the resource-based view (RBV). The scale of social capital is also developed, which is the first integrated measurement of this asset. The findings contribute significantly to the existing knowledge of social capital, the TPB and diversifying agribusiness.

This is the first study to explore the comprehensive effect of the facets of social capital on behavioral intention through behavioral goals and determinants of the TPB under the premises of the RBV. The findings will help emerging economies, for example, Vietnam, where most farmers are family business owners or microscaled entrepreneurs in agriculture.

Globalisation is generally defined as the “denationalisation of clusters of political, economic, and social activities” that destabilize the ability of the sovereign State to control activities on its territory, due to the rising need to find solutions for universal problems, like the pollution of the environment, on an international level. Globalisation is a complex, forceful legal and social process that take place within an integrated whole with out regard to geographical boundaries. Globalisation thus differs from international activities, which arise between and among States, and it differs from multinational activities that occur in more than one nation‐State. This does not mean that countries are not involved in the sociolegal dynamics that those transboundary process trigger. In a sense, the movements triggered by global processes promote greater economic interdependence among countries. Globalisation can be traced back to the depression preceding World War II and globalisation at that time included spreading of the capitalist economic system as a means of getting access to extended markets. The first step was to create sufficient export surplus to maintain full employment in the capitalist world and secondly establishing a globalized economy where the planet would be united in peace and wealth. The idea of interdependence among quite separate and distinct countries is a very important part of talks on globalisation and a significant side of today’s global political economy.

The COVID-19 pandemic has badly affected the global economy. The use of social capital as a resource to diversify agribusiness to get more customers and improve the agricultural supply chain is a considerable issue to explore. This study aims to develop a comprehensive measurement of social capital and examine its effect on the intention to diversify agribusiness. From a supply chain perspective, it uses theory of planned behavior (TPB) and resource-based view (RBV).

The study uses a mixed-methods approach. In-depth interviews, focus group discussions and surveys are used. Structural equation modeling on a sample of 465 respondents in Vietnam was employed to examine the hypothesized relationships.

An integrative measurement scale of social capital from an agricultural supply chain perspective is suggested. The study also shows significant causal relationships amongst social capital, motives, TPB's determinants and the intention to diversify agribusinesses in light of supply chain perspectives.

The study offers a significant contribution to the existing body of knowledge in the literature on social capital, motives, TPB, RBV and supply chain perspectives. The study was executed in Vietnam, where most farmers are smallholders, family business owners or micro-scale entrepreneurs in agriculture.

The complexity and uncertainty of healthcare operations increasingly require agility to safeguard a high quality of care. Using a microfoundations of dynamic capabilities perspective, this study investigates the effects of nurses' implicit voice theories (IVTs) on the behaviors that influence their individual agility.

This research uses quantitative survey data collected from 2,552 Canadian nurses during the fourth wave of the Covid-19 pandemic in the fall of 2021. Structural equation modeling is used to test a conceptual model that hypothesizes the effects of three different IVTs on nurses' creativity, spontaneity, agility and the quality of care they deliver to patients.

The results reveal that voice-inhibiting cognitions (like “suggestions are criticisms for higher-ups”, “I first need a solution or solid data”, and “speaking up has negative repercussions”) negatively impact nurses' creativity and spontaneity in crafting solutions to problems they face daily. In turn, this affects nurses' individual agility as they attempt to adapt to changing circumstances and, ultimately, the quality of care they provide to their patients.

Even if organizations have little control over employees' pre-held beliefs regarding voice, they can still reverse them by developing and nurturing a voice-welcoming culture to boost their workers' agility.

This study combines two theoretical frameworks, voice theory and dynamic capabilities theory, to study how individual-level factors (cognitions and behaviors) contribute to nurses' individual agility and the quality of care they provide to their patients. It answers the recent calls of scholars to study the mechanisms through which healthcare operations can develop and sustain dynamic capabilities, such as agility, and better face the “new normal”.