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The purpose of this paper is to demonstrate the uncontrolled vertical takeoff of an insect-mimicking flapping-wing micro air vehicle (FW-MAV) of 12.5 cm wing span with a body weight of 7.36 g after installing batteries and power control.

The forces were measured using a load cell and estimated by the unsteady blade element theory (UBET), which is based on full three-dimensional wing kinematics. In addition, the mean aerodynamic force center (AC) was determined based on the UBET calculations using the measured wing kinematics.

The wing flapping frequency can reach to 43 Hz at the flapping angle of 150°. By flapping wings at a frequency of 34 Hz, the FW-MAV can produce enough thrust to over its own weight. For this condition, the difference between the estimated and average measured vertical forces was about 7.3 percent with respect to the estimated force. All parts for the FW-MAV were integrated such that the distance between the mean AC and the center of gravity is close to zero. In this manner, pitching moment generation was prevented to facilitate stable vertical takeoff. An uncontrolled takeoff test successfully demonstrated that the FW-MAV possesses initial pitching stability for takeoff.

This work has successfully demonstrated an insect-mimicking flapping-wing MAV that can stably takeoff with initial stability.

The aim of this paper is to investigate the effect of wing kinematics change on force generation produced by flapping wings.

Forces produced by flapping wings are measured using a load cell and compared for the investigation. The measured forces are validated by estimation using an unsteady blade element theory.

From the measurement and estimation, the authors found that flapping wings produced positive and negative lifts when the wings are attached with the +30° and −30°, respectively.

The authors quantified the characteristics of change in the force generation by flapping wings for three wing kinematics. The wing kinematics was modified by changing the initial wing attachment angle.

The result may be applicable to design of control mechanism for an insect‐mimicking flapping‐wing micro air vehicle, which has only wings without control surfaces at its tail.

The preliminary work may provide an insight for design strategy of flapping‐wing micro air vehicles with compact and handy configurations, because they may perform controlled flight even without control surfaces at their tails.

The work included here is the first attempt to quantify the force generation characteristics for different wing kinematics. The suggested way of wing kinematics change can provide a concept for control mechanism of a flapping‐wing micro air vehicle.

Worldwide interest in principal instructional leadership has led to global dissemination of related research findings despite their concentration in a limited set of western cultural contexts. An urgent challenge in educational leadership and management lies in expanding the range of national settings for investigations of instructional leadership. The current study addressed this challenge in the context of Vietnam, a nation with a very limited formal knowledge base in school leadership (Hallinger and Bryant, 2013b; Hallinger and Truong, 2014). The purpose of this paper is to describe the perspectives of Vietnamese primary school principals toward their role as instructional leaders, illuminate instructional leadership practices perceived as important by the principals, and develop a preliminary model of instructional leadership within the Vietnamese education context.

This study was a qualitative inquiry that sought to illuminate the perspectives of Vietnamese principals toward their role as instructional leaders. The research employed semi-structured interviews with 27 primary school principals. Data analysis employed grounded theory in order to synthesize results gathered from the principals into a preliminary conceptual model.

The study yielded a preliminary model of principal instructional leadership in Vietnam. The authors’ model evidences similarities to western models of instructional leadership by including dimensions focusing on setting direction, managing curriculum and instruction and developing the school learning climate. Differences also emerged in terms of two additional constructs, building solidarity and managing external relationships. Other distinctive practices of Vietnamese instructional leaders also emerged in the findings which the authors suggest can be linked to the institutional, political and socio-cultural context of education in this society.

Key limitations arise from the focus on primary schools, small size of the sample, absence of data from the Northern region of Vietnam, and lack of verification of principals’ perspectives with data from other stakeholders.

This study is one of the first empirical studies of Vietnamese school leadership submitted for publication in international refereed journals and the first study that has that sought to conceptualize the instructional leadership role of principals in Vietnam. Moreover, the study illustrates how conceptualizations of school leadership are shaped by features of specific societies. This lends credence to scholarly admonitions concerning the lack of universality of leadership theories.

The purpose of this study is to analyze the effects of integration quality, perceived fluency and assurance quality on brand engagement and trust, and their impacts on brand loyalty in the omnichannel banking setting. It further explores the critical role of personal innovativeness and demographic characteristics as moderating variables for the propositions in the research model.

An online survey of 1,547 respondents was carried out with bank customers located in the three largest cities of Vietnam, who have already used at least two various transactional channels in the past. The results were analyzed by the partial least square-structural equation modeling (PLS-SEM) technique.

The findings denote that integration quality, perceived fluency and assurance quality significantly influence brand trust. Whereas, brand engagement is only affected by integration quality and perceived fluency. Further, brand engagement and trust are substantiated as critical drivers of brand loyalty in omnichannel banking. Customers with high personal innovativeness produce fewer effects of omnichannel properties on brand engagement and trust than other ones. The research context is found to be a significant moderator for the effect of perceived fluency on brand engagement.

This study offers several recommendations for bank managers to develop a successful omnichannel strategy that could enhance brand engagement and trust by improving integration quality, maintaining fluency across various channels and assuring security during the transactional process. It suggests various policies to improve the effectiveness of the omnichannel model towards the clients with high innovativeness.

This research extends the social exchange theory (SET) theory by examining the effects of omnichannel properties on brand engagement, trust and loyalty in the banking sector. The moderating role of personal innovativeness and research context is also explored.

Unsustainable logging and illegal logging for domestic and international trade and trafficking continue to lead to deforestation. It is crucial that Sustainable Development Goal 15 ‘Sustainably manage forests, combat desertification, halt and reverse land degradation, halt biodiversity loss’ is achieved to maintain the livelihoods of people and protect the planet. This is the case in Vietnam as well, where many people, including indigenous groups, rely on the forest for their survival. Drawing on semistructured interviews in Vietnam and a literature review, we investigate how the abuse of forest policies leads to human insecurity. From this, we propose solutions to (1) end unsustainable harvesting and illegal logging (SDG 15.7), (2) integrate the value of forests (culturally and economically) into national and local planning, the development process and poverty elimination strategies (SDG 15.9) and (3) improve the use of forest protection funding provided by international donors.

This study aims to integrate the Social Cognitive Career Theory with the Theory of Planned Behavior to unravel the intricate dynamics of how engaging with ChatGPT affects individuals’ digital entrepreneurial intention, underlying the serial mediation mechanism of the cognitive and reasoned career process.

This research use a cross-sectional design, drawing on a sample of 604 higher education students from six universities in Vietnam. Multiple regression analyses were conducted to test the formulated hypotheses after assessing the reliability and validity of scales through Cronbach’s alpha and confirmatory factor analysis.

The results indicate that ChatGPT adoption significantly increases perceived AI competencies, entrepreneurial opportunity recognition and digital entrepreneurial self-efficacy. Digital entrepreneurial self-efficacy was found to have a positive impact on attitudes toward digital entrepreneurship, which, in turn, fosters digital entrepreneurial intention. ChatGPT adoption thus poses serial indirect impacts on digital entrepreneurial intention through the sequential pathways of enhanced digital entrepreneurial self-efficacy and positive attitudes.

This study’s findings provide valuable recommendations for entrepreneurs, higher education institutions and policymakers.

This research contributes to the entrepreneurship literature by integrating two prominent theoretical frameworks to elucidate how ChatGPT adoption impacts digital entrepreneurial intentions. The serial mediation model expands that understanding of the complex cognitive and reasoned processes involved, providing a novel perspective on the role of AI in entrepreneurship.

This paper aims to facilitate the joint assessment of issues related to the agricultural systems, i.e. agriculture, aquaculture and climate change (CC) response strategies, in the coastal districts with a panel of stakeholders; and to evaluate the level of agreement on the topics under consideration and potentially identify the most promising approaches to assessing CC affecting agricultural systems in the area and identify relevant and adequate response strategies.

Stakeholder Delphi technique – its assessment is an interactive method of qualitative research used to facilitate the interactive participation of varied and conceivably hierarchical and antagonistic stakeholder groups.

The most important result for the province is that the impact of climate change on agro-ecological landscapes (poverty and near river areas) is the duration of cold weather, more frequent and extreme. Moreover, Kendall’s W test gave a score of 0.547, which indicates a “strong” stakeholder agreement and the “confidence in ranks” being “high” in Thai Binh (Vietnam).

The scientific results in this study are intended to serve as relevant knowledge-inputs and direct contributions to capacity-building for the local partners (stakeholders and local authorities). These local partners are engaged in policy-making and effective planning and implementation of climate response measures in the districts in the province of Thai Binh.

The purpose of this study is to investigate factors that affect smallholders' adoption of organic rice production in the Hai Lang district of Vietnam.

This study employed a cross-sectional survey research design. A sample size of 215 was drawn from a total of 455 smallholders. Descriptive and inferential statistics, including a binary logistic regression, were used to analyse the data.

The study concludes that younger female smallholders participating in credit/training programs and community-based organisations, who have a high level of education, a large household size and more experience in rice farming, and who grow mixed crops, have a greater tendency to adopt organic rice production.

A combination of demographic, socio-economic and institutional characteristics of rice smallholders should be considered when promoting organic rice farming practices by smallholders and when choosing organic agricultural development strategies for smallholders in developing countries.

This research provides significant understanding of the determinants of organic rice adoption by smallholder farmers and highlights factors that need to be considered when designing policies to enhance the uptake of organic farming in developing countries.