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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.

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.

This research examines the relationship between market power and liquidity creation in the specific context of bank profitability in the Vietnamese banking sector.

The study applies the methodology proposed by Berger and Bouwman (2009) to demonstrate the creation of bank liquidity through a three-step procedure for investigating the relationship between market power and liquidity creation. The three steps include non-fat liquidity (NFLC), fat liquidity (FLC) and system generalized method of moments estimation for panel data.

This study finds that liquidity creation increases when a bank has high market power. Further, highly profitable banks positively impact the market power of banks with regard to liquidity creation, relative to less profitable banks. Moreover, bank size, capital, economic growth and interest rate negatively influence bank liquidity creation, while credit risk positively relates to bank liquidity creation.

Measurements used in this study are based on the works of Berger and Bouwman (2009). There are specific variations, relative to Basel III. In addition, other variables significantly impact bank liquidity creation that have not been considered in the models, and a quadratic model should have been considered to measure market power and bank liquidity creation.

This study suggests that managers should control the liquidity of their banks by supervising vulnerable characteristics that have been mentioned herein and emphasizing improvements in profitability. Further, the government may consider encouraging banks to generate more liquidity by modifying regulations concerned with market power or reinforcing policies about improving the transparent business environment.

This study characterizes an attempt to examine the influence of market power on the liquidity creation of banks in Vietnam, which represents one of the most dynamic systems in Asia, with several varied participating banks. The current study also examines the same within the specific context of the modifying impact of the profitability of banks.

This study investigates the effects of social media as a social networking tool for donation-based crowdfunding by considering the factors affecting donation intention in the Philippines, such as social influences, motivations, strategic positioning and creative marketing efforts.

A mixed-method approach was used through a survey questionnaire and short focus group discussions (FGD). The researchers used partial least squares structural equation modeling (PLS-SEM) as a statistical tool and qualitative data was analyzed through thematic analysis.

The study found that social experience, perceived donor effectiveness, intrinsic motivation and leveraging creativity positively affected donation intention. In contrast, extrinsic motivation and strategic positioning were found to have no significant effect on donation intention. The qualitative findings support the conclusion by discovering the need to be authentic and transparent to achieve fundraising goals.

Existing research has mainly focused on crowdfunding websites. Also, research regarding the use of social media as a social networking tool for crowdfunding is scarce.

This study provides a deeper understanding of donation crowdfunding and offers insights into developing effective strategies for crowdfunding campaigns through social media.

The findings contribute to the literature on donation crowdfunding by identifying the determinants of a successful campaign through advertised crowdfunding.

Islamic banks have significantly different balance sheets from their conventional counterparts, leading to different implications in relation to liquidity creation compared to conventional banks. This work, first, investigates the liquidity creation of conventional and Islamic banks in Middle Eastern and North African (MENA) countries between 2011 and 2016. It then tests the relationship between liquidity creation and performance of these banks.

It uses the data of 491 commercial banks across 18 MENA countries between 2011 and 2016. The analysis is based on panel data techniques.

The banks created US$18.596 trillion of liquidity, about 28.4% of total assets. Conventional banks created more liquidity compared with Islamic banks. Nevertheless, Islamic banks created more liquidity per asset compared with conventional banks. The regression analysis revealed a significant and negative correlation between liquidity creation and performance of the banks using return on average equity (ROAE) measure. However, no significant relationship is observed between liquidity creation and return on average assets (ROAA) of MENA banks. Moreover, there is no difference between Islamic and conventional banks in the relation between liquidity creation and bank performance.

The data are limited to the period 2011-2016; the period of this study was selected based on yearly data availability from the data source. Accounting measures were used to study the effect of liquidity creation on bank profitability, and the market-based measures were excluded, as there is no uniform sources in these countries that can be used to collect market-based data.

Bank managers must reach a trade-off between the advantages and disadvantages of liquidity creation, as well as consider the negative relationship between liquidity creation and bank performance when making their decisions.

First, to the best of the authors’ knowledge, this work is the first to analyse the relationship between the liquidity creation and performance of conventional and Islamic banks in MENA. Second, this study uses a sample of Islamic and conventional banks in MENA that have detailed information on the Orbis Bank Focus dataset, which is the most comprehensive database of commercial banks in the MENA region.

The study aims to reveal the effects of transformational leadership on nonfamily employee international intrapreneurship with the mediating role of psychological empowerment.

The study sample consists of 379 employees at 132 family export and import firms in Ho Chi Minh City of Vietnam. The data is analyzed by a partial least squares structural equation modeling (PLS-SEM).

The paper reveals that transformational leadership had a positive and significant influence on nonfamily employee international intrapreneurship. The effect of transformational leadership on international intrapreneurship is strongly mediated by psychological empowerment.

Family firms would have to form the architecture and mechanisms for supporting the dedication of nonfamily international intrapreneurship actions with transformational leadership and psychological empowerment.

The paper grants the driving mechanism of the transformational leadership on nonfamily employee international intrapreneurship through the mediating role of employee psychological empowerment in the context of family businesses in an emerging market.

This study aims to analyze the contagious effects of economic policy uncertainties in the USA on the economies of its important trading partners, such as Japan, Canada, Mexico and the Eurozone.

In the study using the uncertainty index created by Baker et al. (2016), the interaction between variables was analyzed with structural VAR (SVAR) models.

According to the results obtained from the analysis, economic policy uncertainties in the USA had significant effects on the economies of its high-volume trading partners. The internal debt crisis experienced in the Eurozone after the 2008 crisis caused the European Central Bank to respond to the economic policy uncertainties in the USA with contractionary monetary policies, unlike other countries. In addition to these results, Mexico, which has a more fragile economic structure than other countries in the analysis, was more impacted by increasing uncertainties, as expected.

The present study aimed to bring a new perspective to the literature by evaluating the contagiousness of local uncertainty in the globalizing world and the monetary policies implemented as a precaution against this situation on an empirical plane.

The current study aims to investigate the impacts of two behavioral biases, namely, loss aversion and overconfidence on the performance of US companies. First, the impact of loss aversion on the economic performance of companies was assessed. Second, the impact of overconfidence on market performance was discussed.

This study used around 6,777 quarterly observations on the population of US-insured industrial and services companies over the 2006-2016 period. Ordinary least squares (OLS) regression in two panel data models were used to test the hypotheses formulated for the study.

It was documented that the loss-aversion bias negatively affects the economic performance of companies and this is achieved for both sectors. In contrast, the findings suggest that overconfidence positively affects market performance of industrial firms but negatively affects market performance in service firms. Further robust evidence was found that overconfidence bias seems to be dominant, and hence, investors may tend to be more overconfident rather than more loss-averse.

This research can be extended by focusing on the following question: What is the impact of the contradictory (positive and negative) effects of an investor's loss aversion and overconfidence on the US company performance in case of realization of a stock market crisis or stock market crash?

Keberkesanan penyampaian sesuatu maklumat memerlukan individu, alat mahupun saluran yang unggul dan bersesuaian. Usaha ini haruslah dirancang dan dipertimbangkan dengan teliti oleh pihak tertentu agar setiap apa yang ingin disampaikan dan dilaksanakan itu dapat diberigakan dengan mudah dan berkesan. Dari itu, penggunaan bahasa retorik dilihat sebagai batu loncatan yang memberikan keyakinan dan tahap keberkesanan yang tinggi bagi sesebuah wacana yang disampaikan tersebut. Kewibawaan retorik sebagai seni yang mempengaruhi bukan sahaja berperanan untuk memperkukuhkan kekuasaan mahupun mempengaruhi fikiran dan emosi orang lain namun sebaliknya mampu menstimulasikan keseimbangan hubungan sosial yang terbentuk melalui sistem pemerintahan sesebuah negara. Melalui penyelidikan ini, setiap ciri khas retorik dapat diketengahkan dengan menghuraikan peranan dan fungsi-fungsi yang dimainkan oleh jenis-jenis retorik dalam penulisan sesebuah wacana. Hal ini khusus bagi mengilustrasikan idea, gagasan mahupun suatu fakta terhadap sesuatu pendekatan dengan cara yang kreatif dan terbaik. Di samping itu, keutamaan bagi penerapan bahasa retorik dalam perutusan kerajaan seharusnya dapat diperkasakan sewajarnya dengan menjadikannya sebagai anjakan paradigma ke arah perpaduan dan nilai kesaksamaan dalam masyarakat. Justeru, kajian ini memanfaatkan Teori Retorik Moden oleh Enos dan Brown (1993) sebagai landasan utama dalam menganalisis sejumlah 20 perutusan rasmi berkaitan jangkitan covid-19 di Negara Brunei Darussalam. Berdasarkan pemerhatian dan penganalisisan yang dijalankan, hanya empat jenis retorik yang diaplikasikan dalam wacana tersebut. Kesimpulan statistik merangkumi 34% teknik pendedahan, 30% teknik penerangan, 33% teknik pemujukan dan hanya 3% bagi teknik penghujahan. Dapatan penyelidikan ini membuktikan bahawa penggunaan bahasa retorik dalam perutusan rasmi kerajaan adalah amat penting dalam memperkukuhkan sistem pemerintahan negara serta mampu melestarikan cara hidup yang relevan dan berkualiti.

The effectiveness of delivering information requiresindividuals, tools or channels that are superior and appropriate. This effort must be planned and considered carefully so that everything that is to be conveyed and implemented can be conveyed easily and effectively. Therefore, the use of rhetorical language is regarded as a stepping stone that provides confidence and a higher level of effectiveness. `Rhetoric as an influential art not only plays a role in strengthening power or influencing the thoughts and emotions of others but also stimulate sthe balance of social relations. Through this research, each rhetorical feature is highlighted to discuss its role and functions in the discourse. Using Enos and Brown’s Modern Rhetorical Theory (1993), a total of 20 official conferences on the latest developments of the spread of covid-19 infection were discussed. Findings have shown that there were four main types of rhetoric, i.e. Statistical conclusions which include 34% of expository techniques, 30% of descriptive, 33% of persuasion and only 3% for argumentation techniques. This also implies that rhetoric language is very important in ensuring the dissemination of knowledge among the institution and people is effective and and transparent.

The purpose of this review is to comprehensively consider the material properties and processing of additive titanium alloy and provide a new perspective for the robotic grinding and polishing of additive titanium alloy blades to ensure the surface integrity and machining accuracy of the blades.

At present, robot grinding and polishing are mainstream processing methods in blade automatic processing. This review systematically summarizes the processing characteristics and processing methods of additive manufacturing (AM) titanium alloy blades. On the one hand, the unique manufacturing process and thermal effect of AM have created the unique processing characteristics of additive titanium alloy blades. On the other hand, the robot grinding and polishing process needs to incorporate the material removal model into the traditional processing flow according to the processing characteristics of the additive titanium alloy.

Robot belt grinding can solve the processing problem of additive titanium alloy blades. The complex surface of the blade generates a robot grinding trajectory through trajectory planning. The trajectory planning of the robot profoundly affects the machining accuracy and surface quality of the blade. Subsequent research is needed to solve the problems of high machining accuracy of blade profiles, complex surface material removal models and uneven distribution of blade machining allowance. In the process parameters of the robot, the grinding parameters, trajectory planning and error compensation affect the surface quality of the blade through the material removal method, grinding force and grinding temperature. The machining accuracy of the blade surface is affected by robot vibration and stiffness.

This review systematically summarizes the processing characteristics and processing methods of aviation titanium alloy blades manufactured by AM. Combined with the material properties of additive titanium alloy, it provides a new idea for robot grinding and polishing of aviation titanium alloy blades manufactured by AM.