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The development of robust control algorithms for the position, velocity and trajectory control of unmanned underwater vehicles (UUVs) depends on the accuracy of their mathematical models. Accuracy of the model is determined by precise estimation of the UUV hydrodynamic parameters. The purpose of this study is to determine the hydrodynamic forces and moments acting on an underwater vehicle with complex body geometry and moving at low speeds and to achieve the accurate coefficients associated with them.

A three-dimensional (3D) computer-aided design (CAD) model of UUV is designed with one-to-one dimensions. 3D fluid flow simulations are conducted using computational fluid dynamics (CFD) software programme in the solution of Navier Stokes equations for laminar and turbulent flow analysis. The coefficients depending on the hydrodynamic forces and moments are determined by the external flow analysis using the CFD programme. The Flow Simulation k-ε turbulence model is used for the transition from laminar flow to turbulent flow. Hydrodynamic properties such as lift and drag coefficients and roll and yaw moment coefficients are calculated. The parameters are compared with the coefficient values found by experimental methods.

Although the modular type UUV has a complex body geometry, the comparative results of the experiments and simulations confirm that the defined model parameters are accurate and close to the actual experimental values. In the proposed k-ε method, the percentage error in the estimation of drag and lifting coefficients is decreased to 4.2% and 8.39%, respectively.

The model coefficients determined in this study can be used in high-level control simulations which leads to the development of robust real-time controllers for complex-shaped modular UUVs.

The Lucky Fin UUV with 4 degrees of freedom is a specific design and its CAD model is first extracted. Verification of simulation results by experiments is generally less referenced in studies. However, it provides more precise parameter identification of the model. Proposed study offers a simple and low-cost experimental measurement method for verification of the hydrodynamic parameters. The extracted model and coefficients are worthwhile references for the analysis of modular type UUVs.

This paper aims to illustrate the scope and challenges of using computer-aided content analysis in international marketing with the aim to capture consumer sentiments about COVID-19 from multi-lingual tweets.

The study is based on some 35 million original COVID-19-related tweets. The study methodology illustrates the use of supervised machine learning and artificial neural network techniques to conduct extensive information extraction.

The authors identified more than two million tweets from six countries and categorized them into PESTEL (i.e. Political, Economic, Social, Technological, Environmental and Legal) dimensions. The extracted consumer sentiments and associated emotions show substantial differences across countries. Our analyses highlight opportunities and challenges inherent in using multi-lingual online sentiment analysis in international marketing. Based on these insights, several future research directions are proposed.

First, the authors contribute to methodology development in international marketing by providing a “use-case” for computer-aided text mining in a multi-lingual context. Second, the authors add to the knowledge on differences in COVID-19-related consumer sentiments in different countries. Third, the authors provide avenues for future research on the analysis of unstructured multi-media posts.

A lot has been discussed about Peter Drucker, and there exists significant written content admiring or criticizing his work as a management writer. This paper aims to offer a holistic analysis of Peter Drucker’s written contributions to better understand his views of society, government and organizations of all kinds.

Many have written about Peter Drucker and his considerable impact on the practical and philosophical foundations of modern management. Yet, there has been no systematic scholarly evaluation of Drucker as a writer, although many have praised and criticized his written work on management. In this study, the authors offer an analysis of Peter Drucker’s written contributions to evaluate his central contributions, as well as how he communicated his ideas on society and management.

A comprehensive analysis of Drucker’s word usage and writing style throughout his writing career forms an evidence-based approach to better understand his viewpoints and objectively evaluate the criticisms surrounding his work.

This research contributes to a better understanding of Peter Drucker’s central contributions, concerns and sentiments, as it relates to not only business management but also to his views of society, government and organizations of all kinds. A reconsideration of Drucker as a writer presents possible implications for the practice of management.

The curve construction on surfaces is becoming more and more important in computer-aided design (CAD), computer graphics (CG) and the other related fields. This problem is often encountered in NC machining, tool path generation, automated fiber placement and so on. However, designing curves on curved surfaces is quite different from constructing a curve in Euclidean space. Therefore, the traditional methods of curve design are not suitable for constructing a continuous curve on surface. The authors need to perform interpolation directly on surface so that the final target curve is embedded into the given surface and also meets the continuous conditions.

Firstly, adopting a series of Hermite blending functions, the authors design a space curve passing the given knots on the point-cloud surface. Then, the authors construct a class of directrixes that are adopted to determine vector fields for projection. Finally, a complete G2 continuous curve embedded in point-cloud surfaces is constructed by solving the first-order ordinary differential equations (ODEs).

The authors’ main contribution is to overcome the problem of constructing G¹ and G² continuous curves on point-cloud surfaces and the authors’ schemes are based on the projection moving least square (MLS) surfaces and traditional differential geometric.

Based on the framework of projection MLS surfaces, a novel method to overcome the problem of constructing G² continuous curves on point-cloud surfaces is proposed.

This study aims to investigate the influence of sociodemographic characteristics, perceived risks, health and nutritional motives and taste preference on at-home fish consumption.

Data were collected from a nationally representative sample of people responsible for food purchasing in households, using the CAWI (computer-aided web interviewing) method. The eligible study sample comprised 977 participants in Croatia and 967 in Italy, who reported fishery products consumption in the previous 12 months. A questionnaire was used to examine sociodemographic characteristics, fish consumption frequency and factors affecting fish consumption. Determinants of white and fatty fish consumption were estimated with ordered probit models, along with marginal effects for each factor in the models.

Common positive determinants of white and fatty fish consumption in Croatia and Italy were health and nutritional motives (p < 0.001, p = 0.001, p < 0.001, p = 0.010), taste preference (p < 0.001, p < 0.001, p = 0.001, p = 0.001) and maritime nature of the living region. The common negative determinant of white and fatty fish consumption in Croatia and Italy was financial risk (p < 0.001, p < 0.001, p < 0.001, p = 0.005). The country-specific positive determinant in Croatia was the number of household members (p < 0.001), while negative determinants for white and fatty fish were functional risk (p = 0.004, p = 0.013), number of children (p = 0.030, p = 0.001) and female gender (for fatty fish) (p = 0.028). In Italy, older age negatively affected (p < 0.001) fish consumption, while number of children (p = 0.009) and household income positively affected white fish consumption.

An adequate probabilistic model of national representative samples ensures credibility of results. Policy and marketing activities are proposed that can encourage higher fish consumption.

The rapid development of three-dimensional (3D) printing makes it familiar in daily life, especially the fused deposition modeling 3D printers. The process planning of traditional flat layer printing includes slicing and path planning to obtain the boundaries and the filling paths for each layer along the vertical direction. There is a clear division line through the whole fabricated part, inherited in the flat-layer-based printed parts. This problem is brought about by the seam of the boundary in each layer. Hence, the purpose of this paper is to propose a novel helical filling path generation with the ideal surface-plane intersection for a rotary 3D printer.

The detailed algorithm and implementation steps are given with several worked examples to enable readers to understand it better. The adjacent points obtained from the planar slicing are combined to generate each layer's helical points. The contours of all layers are traversed to obtain the helical surface layer and helical path. Meanwhile, the novel rotary four-degree of freedom 3D printer is briefly introduced.

As a proof of concept, this paper presents several examples based on the rotary 3D printer designed in the authors’ previous research and the algorithms illustrated in this paper. The preliminary experiments successfully verify the feasibility and versatility of the proposed slicing method based on a rotary 3D printer.

This paper provides a novel and feasible slicing method for multi-axis rotary 3D printers, making manufacturing thin-wall and complex parts possible. To further broaden the proposed slicing method’s application in further research, adaptive tool path generation for flat and curved layer printing could be applied with a combination of flat and curved layers in the same layer, different layers or even different parts of structures.

As a business executive and philanthropist, Mary Kay Ash is legendary as a glass-ceiling breaker. With the belief that Mary Kay Ash is both modern and relevant, while simultaneously legendary, the overall purpose of this paper is to explore the role of Mary Kay Ash as an influential entrepreneur. This research responds to the call by Cogliser and Brigham (2004) for an increased understanding of how entrepreneurial leaders influence, challenge, inspire and develop followers.

Following on research by Hoppe (2013), this objective was accomplished via a pentadic analysis of Mary Kay Ash’s rhetoric aimed to influence the mental mindset of readers (followers) over the course of generations. Burke’s pentad was the sense-making tool used for examining Ash’s rhetoric of influence as an entrepreneurial leader. The data used in the pentadic analysis were also analyzed via Linguistic Inquiry and Word Count (LIWC) and IBM Watson Emotion Analysis to see where analyses might converge or diverge.

Based on the analysis of her written work, Mary Kay Ash resided at the intersection of leadership and entrepreneurship and, in so doing, was an influencer. Her primary rhetorical approach to influencing was idealism. Interwoven in her writings, she also exhibited both pragmatism and realism. She knew that she had to start the business to have the future she desired and that she needed to train her team appropriately for success to be forthcoming. The motivation in Mary Kay Ash’s rhetoric was that of influencing people so they would be the best that they could be.

Qualitative research brings with it an array of inevitable research problems. Pentadic analysis cannot be judged by the basic objective standards of reliability and validity because objective reality does not exist in personal interpretation. That is, one person as a critic cannot be impartial because the interpretation is only one personal way of viewing the data and another critic might view the same pentads and come up with different ratios. With this subjectivity in mind, however, the data used in the pentadic analysis were also analyzed via LIWC and IBM Watson Emotion Analysis to see where analyses might converge or diverge.

The findings from this research denote clearly that Mary Kay Ash was a forerunner of the modern day influencer. As a primogenitor of the influencer marketing phenomenon, Mary Kay Ash’s entrepreneurial legacy is expected to continue through generations of followers. This finding speaks to the importance of today’s entrepreneurs using the spoken and written word to influence others and create a lasting organizational legacy.

Countless scholars have used pentadic analysis, with a variety of artifacts, to examine the motives behind the rhetoric. However, rhetoric as a means of persuasion and influence has received little attention within the context of the written works by management gurus (Jones et al., 2009), and, aside from the exploration by Berglund and Wigren (2012), the narrative of entrepreneurial influence has not benefitted from close examination.

The purpose of this study is to develop and describe a process which can be applied to develop new methods in the context of preliminary aircraft sizing in a successful and efficient way.

The tasks to development new aircraft sizing methods are systematically analyzed. In particular, repeating and nonrepeating tasks and common or unique tasks. Then ordered in a sequence and described generically.

A development process for new aircraft design methods which are necessary for new technologies or configurations is introduced and explained step by step.

Introducing the capability to deal with new technologies or configurations, aircraft design tools or aircraft concepts requires new sizing methods.

The paper presents a systematic approach which can be used to develop a great amount of new sizing methods with a comparable usability and quality standard in an efficient and effective way.

Particles bed binding by selective cement activation (SCA) method is a computer-aided manufacturing (CAM) technique used to produce cementitious elements. A computer-aided design file is sliced to generate G-codes before printing. This paper aims to study the effect of key input parameters for slicer software on the final properties of printed products.

The one factor at a time (OFAT) methodology is used to investigate the impact of selected parameters on the final properties of printed specimens, and the causes for the variations in outcomes of each variable are discussed.

Finer aggregates can generate a more compact layer, resulting in a denser product with higher strength. Fluid pressure is directly determined by voxel rate (r_V); however, high pressures enable better fluid penetration control for fortified products; for extreme r_Vs, residual voids in the interfaces between successive layers and single-line primitives impair mechanical strength. It was understood that printhead movement along the orientation of the parts in the powder bed improved the mechanical properties.

The design of experiment (DOE) method assesses the influence of process parameters on various input printing variables at the same time. As the resources are limited, a fractional factorial plan is carried out on a subset of a full factorial design; hence, providing physical interpretation behind changes in each factor is difficult. OFAT aids in analyzing the effect of a change in one factor on output while all other parameters are kept constant. The results assist engineers in properly considering the influence of variable variations for future DOE designs.

The purpose of this article is to increase the understanding of how improvements can be facilitated in a public service containing multiple actors in terms of identifying, aligning and prerequisites for the improvements.

The research utilizes an interactive research approach where data were gathered though a conference, workshop and a survey. The study alternately combines quality management methods such as affinity and interrelationship diagrams with computer aided text mining and latent semantic analysis.

The research shows that practitioners must consider interconnectedness between improvements and benefits that are crossing organizational levels of the public service system as well as professional borders. In public service systems, the complex reality can be better understood when improvements and benefits are classified into different organizational layers and an interconnectedness and sequence of improvement areas are acknowledged.

The research is set in the Swedish public service of the tax-paid sick leave insurance. Future research would benefit by investigating similar cases in other nations and other services.

The used methodology can be applied by practitioners to enhance a unified understanding of the system required to improve. The study also guides practitioners for how to support, relive hinders and prioritize improvements.

The research fills a gap of understanding of improvements in public services with multiple actors. As this area is difficult to improve, a novel combination of qualitative and quantitative methods paved the way for deeper and more unified understanding of the system.