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Unlike conventional aircraft, birds can glide without a vertical tail. The purpose of this paper is to analyse the influence of dihedral angle spanwise distribution on lateral-directional dynamic stability by the simulation, calculation in the development of the bird-inspired aircraft and the flight testing.

The gliding magnificent frigatebird (Fregata magnificens) was selected as the study object. The geometric and mass model of the study object were developed. Stability derivatives and moments of inertia were obtained. The lateral-directional stability was assessed under different spanwise distributions of dihedral angle. A bird-inspired aircraft was developed, and a flight test was carried out to verify the analysed results.

The results show that spanwise distribution changing of dihedral angle has influence on the lateral-directional mode stability. All of the analysed configurations have convergent Dutch roll mode and rolling mode. The key role of dihedral angle changing is to achieve a convergent spiral mode. Flight test results show that the bird-inspired aircraft has a well-convergent Dutch roll mode.

The theory that birds can achieve its lateral-directional stability by changing its dihedral angle spanwise distribution may explain the stability mechanism of gliding birds.

This paper helps to improve the understanding of bird gliding stability mechanism and provides bio-inspired solutions in aircraft designing.

To unlock social media’s value, this study aims to integrate insights from several theoretical perspectives and the relevant literature, developing an extended social media analytics framework. It identifies the stages underlying the social media analytics process and tests the framework in three important and interconnected areas: social media (Twitter), new product adoption (iWatch and Google Glass) and social media analytic techniques (text mining and sentiment analysis).

Based upon a systematic review of different research approaches, theories and media types, this paper presents and tests an extended framework in three important and interconnected areas mentioned above.

This paper offers a theory-driven social media analytics framework. It validates the framework by providing concrete processes, examples, evidence and insights related to three chosen areas mentioned above, thereby helping managers create effective and efficient social media and new product development strategies.

This paper integrates insights from theories of the middle range (Merton, 1949), Campbell’s (1965) model of sociocultural evolution and Fan and Gordon’s (2014) social media analytics framework, developing its own extended social media analytics framework and validating it in three important and interconnected areas mentioned above. This paper demonstrates not only how the proposed framework can be applied to the context of new product development, but also how social media are transforming research approaches (qualitative, quantitative and mixed method) and the very nature of business itself (increased importance of digital business).

This paper aims to examine how a stereotype threat, which entails being aware of a negative stereotype about one’s social group (e.g. gender), affects consumers’ price perceptions.

The authors conducted four studies to examine the effect of a stereotype threat on consumers’ perceptions of a product’s price–quality relationship.

This study found that being aware of a negative stereotype about one’s social group (i.e. gender here) led consumers to use price more as a quality indicator. This study also determined that reappraisal – an alternative way of coping with stereotype threats – reduced the impact of a stereotype threat and, subsequently, decreased reliance on price to infer quality.

This research contributes to the consumer decision-making literature by examining stereotype threat effect in in-store product purchasing contexts; provides theoretical contributions to the processing of price information by exploring the role of a stereotype threat in price perceptions and revealing that impairment of consumers’ working memory resources affects price perceptions; adds to the existing stereotype threat literature by investigating the effect of a stereotype threat on systematic versus heuristic information processing; and advances the stress and coping literature by suggesting that consumers adopting a reappraisal strategy cope better with a stereotype threat than when opting for a suppression strategy.

This research provides important implications for consumers. For example, the findings suggest that consumers who would like to avoid paying more for stereotype-associated products may adopt reappraisal to cope with a stereotype threat. Reappraisal may allow consumers to use fewer cognitive resources when coping with stereotype threats, thus minimizing the possibility that they might overpay for high-priced products.

This research uniquely examines the effect of a stereotype threat on consumers’ price perceptions and the role of reappraisal in this effect.

This study aims to provide a practical strategy for customer service and salesforce from the basis of behavioral economics. When customers thought they missed a discount but eventually could get the deal, they perceived that they had obtained more value. This research defines such a conversion effect between gain and loss accounts, demonstrates its impact in marketing settings and provides the salesforce a tactic to increase sales and quality of customer service to improve the consumer experience in the social customer journey.

Three experiments were conducted in a behavioral lab and online setting. Participants were randomly assigned to 2 (gain vs loss) × 2 (converted vs simple) between-subjects designs in the first two experiments and 2 (gain vs loss) × 2 (converted vs simple) × 2 (high price vs low price) in the third experiment. Analysis of variance was conducted to analyze the data. Mediation and moderation analyses were also conducted to identify the mediator and moderator in the model.

The conversion between gain and loss mental accounts exists, and the converted gains are more likely to lead consumers to make purchases with a once-lost discount than simple gains. This conversion effect is mediated by consumers’ implemental mindset activated by the conversion and moderated by price.

This research shows that mental accounts of gains and losses can be dynamically converted to one another. It provides a managerial tactic for salesforces and customer service to lead consumers to make a purchase decision right away. This is especially important when they aim to enhance the consumer experience in the social customer journey.

The purpose of this paper is to propose an identification method of acquiring aircraft mode characteristics based on fast Fourier transform and half-power bandwidth method, aiming at the common oscillation met in flight test.

The feasibility of this method is demonstrated through derivation; the robustness analysis is conducted through three examples, and finally the method was applied on a set of sideslip angle record from flight test.

The derivation and numerical analysis both show that the presented method can have high accuracy and good robustness under coupled mode and noise condition.

The method proposed is of robustness, and it is concise and easy to apply on flight data record.

This paper demonstrates the feasibility of half power bandwidth to be applied on oscillation mode characteristics identification from flight data record, which is different from other method applied.

The typical approach of modeling the aerodynamics of an aircraft is to develop a complete database through testing or computational fluid dynamics (CFD). The database will be huge if it has a reasonable resolution and requires an unacceptable CFD effort during the conceptional design. Therefore, this paper aims to reduce the computing effort required via establishing a general aerodynamic model that needs minor parameters.

The model structure was a preconfigured polynomial model, and the parameters were estimated with a recursive method to further reduce the calculation effort. To uniformly disperse the sample points through each step, a unique recursive sampling method based on a Voronoi diagram was presented. In addition, a multivariate orthogonal function approach was used.

A case study of a flying wing aircraft demonstrated that generating a model with acceptable precision (0.01 absolute error or 5% relative error) costs only 1/54 of the cost of creating a database. A series of six degrees of freedom flight simulations shows that the model’s prediction was accurate.

This method proposed a new way to simplify the model and recursive sampling. It is a low-cost way of obtaining high-fidelity models during primary design, allowing for more precise flight dynamics analysis.

The purpose of this study was to analyze the interest conflicts and strategy evolution process of various stakeholders in the process of homestead withdrawal, to reveal which key factors can balance the interests of all parties.

The authors developed an evolutionary game theoretical framework for homestead withdrawal in Yujiang District, Jiangxi Province, China. The authors compared the dynamic process of strategy change in different situations based on system dynamics.

Compared with indirect external factors, direct economic factors, such as increasing compensation standards or increasing fines, are more likely to encourage peasants to withdraw from their homesteads. The dynamic subsidy strategy can increase the probability of peasants withdrawing from their homestead. Additionally, awarding officials with promotions can effectively encourage local governments during the process.

Previous studies have conceptualized farmers' willingness to withdraw from their homestead as a static process, ignoring the underlying dynamism. This paper analyzes the game mechanism among the stakeholders of the homestead withdrawal process from a dynamic perspective, to provide efficient suggestions regarding policymaking for homestead withdrawal.

As there is inclusive evidence on relationship between board characteristics and firm performance in the Thai context, and mixed findings of this relationship are usually reported from previous studies, this study tries to clarify a reason for the mixed finding by determining the impact of board structures on different quantile levels of firm performance. Building on extant literature and using a developed econometric technique, the Quantile Analysis, on a sample of 446 listed firms in Thailand for a 15-year period ranging from 2000 to 2014, empirical evidence is provided which is consistent with prior studies that some characteristics of the board as the core mechanisms of corporate governance, i.e., board independence, board size, board meeting frequency, and dual role leadership on board, have significant influence on performance of Thai firms. In particular, when considering different quantile levels of firm performance, board structures are found to have different effects across quantile of performance distribution. Board independence and dual role leadership on board are found to have a significant influence on only moderate-performing firms, while board size and board meeting frequency are revealed as having significant impact on only firms with high-performance which need more effectiveness of the board in overseeing and supervising decision-making of the executives. Thus, these findings indicate that considering different quantile levels of firm performance for the board structures and performance relationship should be a reason of previous mixed findings. Moreover, the findings should be important information in encouraging better understanding an optimal governance system in Thailand for related stakeholders such as policymakers, corporate firms, and investors.

The main purpose of the study is to examine the influence of family directors on the firm performance of public listed companies (PLCs) in Malaysia. This study provides empirical evidence on the agency problems between controlling shareholders and minority interests in the concentrated ownership setting.

Samples of the study are 112 PLCs in year 2006. Two measures of firm performance are used: return on assets (ROA) and Tobin’s Q. Managerial ownership refers to the percentage shareholdings of executive directors with direct and indirect holdings. It was further categorized into family ownership and non-family ownership.

In relation to ROA, managerial ownership is found positively significant. The results also show that the positive relationship between managerial ownership is contributed by the managerial-non-family ownership. In relation to Tobin’s Q, the results show a U-shape with turning point at 31.38% for managerial ownership and 28.29% for the managerial-family ownership. The results found significant and positive relationships between managerial ownership and both measures of firm performance which indicates that managerial ownership and family ownership yield greater efficiency.

The study highlights the effects of corporate governance on ROA and Tobin’s Q are somewhat different. It provides some evidence on the need to use appropriate measure of firm performance. The significant relationship supports the argument of Chami (1999), Fama and Jensen (1983), and DeAngelo and DeAngelo (1985) and empirical evidence of Lee (2004) that family ownership enhances monitoring activities.

Differentiating the types of managerial ownership into family and non-family categories enriches our knowledge about who actually contributes to the improved performance.

With the increase in uncertainty around the globe, an intensifying interest is seen in Economic Policy Uncertainty (EPU) as a topic of research. Researchers worldwide understand the significance of the impact of EPU on the country's development. EPU has a far-reaching impact as uncertainty shocks in one part of the world resonate worldwide due to the level of interconnectivity, globalization and quick communication. In order to facilitate these researchers, this study presents a bibliometric analysis of the existing research in this field using VOS viewer software, by consolidating all the studies from Scopus indexed journal articles, conference proceedings and review papers published in English language from 2006 to 2022. Bibliometric analysis on EPU has rarely been performed. The analysis identifies the publication trends, journal-wise citation, most influential authors, countries, institutions, keyword co-occurrence and authors of different countries who have collaborated for the research in the field. Finally, 1,055 papers were used for bibliometric analysis. The findings depicted that the most cited article on EPU is ‘Measuring economic policy uncertainty’ by Baker et al. (2016) and the most prolific author appears to be Rangan Gupta from University of Pretoria which as an institution also has the maximum publications on this topic. The Journal Finance Research Letters has published the greatest number of researches on EPU. This chapter also summarizes the limitations of the study along with new areas of research.