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The purpose of this paper is to consider divergence of composite plate wings as well as slender wings with thin-walled cross-section of small-size airplanes. The main attention is paid to establishing of closed-form mathematical solutions for models of wings with coupling effects. Simplified solutions for calculating the divergence speed of wings with different geometry are established.

The wings are modeled as anisotropic plate elements and thin-walled beams with closed cross-section. Two-dimensional plate-like models are applied to analysis and design problems for wings of large aspect ratio.

At first, the equations of elastic deformation for anisotropic slender, plate-like wing with the large aspect ratio are studied. The principal consideration is delivered to the coupled torsion-bending effects. The influence of anisotropic tailoring on the critical divergence speed of the wing is examined in closed form. At second, the method is extended to study the behavior of the large aspect ratio, anisotropic wing with box-like wings. The static equations of the wing with box-like profile are derived using the theory of anisotropic thin-walled beams with closed cross-section. The solutions for forward-swept wing with box-like profiles are given in analytical formulas. The formulas for critical divergence speed demonstrate the dependency upon cross-sectional shape characteristics and anisotropic properties of the wing.

The following simplifications are used: the simplified aerodynamic theory for the wings of large aspect ratio was applied; the static aeroelastic instability is considered (divergence); according to standard component methodology, only the component of wing was modeled, but not the whole aircraft; the simplified theories (plate-lime model for flat section or thin-walled beam of closed-section) were applied; and a single parameter that defines the rotation of a stack of single layers over the face of the wing.

The simple, closed-form formulas for an estimation of critical static divergence are derived. The formulas are intended for use in designing of sport aircraft, gliders and small unmanned aircraft (drones). No complex analysis of airflow and advanced structural and aerodynamic models is necessary. The expression for chord length over the span of the wing allows for accounting a board class of wing shapes.

The derived theory facilitates the use of composite materials for popular small-size aircraft, and particularly, for drones and gliders.

The closed-form solutions for thin-walled beams in steady gas flow are delivered in closed form. The explicit formulas for slender wings with variable chord and stiffness along the wing span are derived.

This study examined the relationships of normative and affective facets of organizational commitment with experienced burnout within the framework of the Confucian‐based Chinese culture. Data for this exploratory work were collected through a questionnaire survey of 147 employees of a Chinese‐owned bank in Hong Kong. The questionnaire consisted of scales on experienced burnout, organizational commitment, and work perceptions. Results showed that the mean score for normative commitment was significantly higher than the mean score for affective commitment. Regression analysis indicated that when age, tenure, organizational level, and work perceptions were controlled, normative commitment had a significant positive effect on experienced burnout, whereas affective commitment had no significant impact. Results are interpreted in the context of a Confucian‐based Chinese managerial ideology and implications are drawn for future research.

The riveting process is a metal forming process involving complex elastic-plastic deformation, which will induce a compressive residual stress field and cause local distortions in the connecting areas. Regarding to the aircraft panel assemblies with plenty of rivets, the global deformation is inevitable and undesired, leading difficulties to downstream assembly processes. This paper aims to present a new method for the local distortion calculation and the global deformation prediction of sheet panel assemblies during the automated riveting process.

In this paper, a simplified algebraic study is presented to analyze the local distortion of single countersunk rivet joint with the consideration of the barrel-like shape of the driven head and the through-thickness variations along the rivet shank. Then, an equivalent rivet unit is proposed based on the result of the algebraic study and embedded into the global-level model for the prediction of the overall distortions of riveted panels.

The algebraic study is able to reach a more precise contour of the deformed rivet than the traditional assumption of cylindrical deformations and rapidly determine the equivalent coefficients of the riveting unit. The result also shows an industrial acceptable accuracy of the prediction for the global deformations of the double-layered panel assemblies widely used in the aircraft panel structures.

A new local-global method for predicting the deformations of the riveted panel assembly based on the algebraic study of the local distortions is proposed to help the engineers in the early design stages or in the assembly process planning stage.

Normalement la science a la tâche et le mérite de définir les notions et d'écarter de celles‐ci ce qui demeure incertain. Le tourisme pourrait aussi recourir à son assistance, on sait que la science ne lui est pas restée indifférente; c'est sous cet angle par exemple qu'il est enseigné aux universités de Berne et de St‐Gall. Nous ne voulons pourtant pas ici entrer dans ce domaine. Dans la mesure du possible, nous nous contenterons seulement de faire appel à l'objectivité qui caractérise les méthodes scientifiques et de nous inspirer de leur précision.

The purpose of this paper is achieving a leader–follower formation of unmanned aerial vehicles which is a cooperative scenario inspired by formation flying of living organisms such as geese. Designing a control strategy based on only vision measurement (without radio communication) and keeping connectivity in vision are important challenges in the formation flying problem which is the base of formation flying in living organisms.

To achieve the mentioned purposes, a feedback linearization technique is used. Moreover, a Takagi-Sugeno-based supervisory control strategy for visibility maintenance combined with an acceleration estimator to compensate the leader maneuvers is proposed.

The authors conclude that by using practical seeker sensors, all the mentioned objectives (under the proposed strategy) can be satisfied.

Keeping formation and visibility maintenance in the presence of the leader maneuver are the main contributions of the paper.

Selective laser melting (SLM) enables the fabrication of lightweight and complex metallic structures. Support structures are required in the SLM process to successfully produce parts. Supports are typically lattice structures, which cost much time and material to manufacture. Besides, the manufacturability of these supports is undesirable, which may impact the quality of parts or even fail the process. The purpose of this paper is to investigate the efficiency and mechanical properties of advanced internal branch support structures for SLM.

The theoretic weight of a branch support and a lattice support of the same plane were calculated and compared. A group of standard candidates of branch support structures were manufactured by SLM. The weight and scanning time of specimens with different design parameters were compared. Then, these samples were tested using an MTS Insight 30 compression testing machine to study the influence of different support parameters on mechanical strength of the support structures.

The results show that branch type supports can save material, energy and time used needed for their construction. The yield strength of the branch increases with the branch diameter and inclined branch angle in general. Furthermore, branch supports have a higher strength than traditional lattice supports.

To the best of the authors’ knowledge, this is the first work investigating production efficiency and mechanical properties of branch support structures for SLM. The findings in this work are valuable for development of advanced optimal designs of efficient support structures for SLM process.

Retail marketing is in the midst of an evolution. The paradigm is shifting from a product-centric to a consumer-centric focus, with a particular emphasis on understanding how consumers transition from harboring an interest in a product to actually purchasing that product. In response, shopper marketing, and in-store marketing (ISM) in particular, have emerged as important mechanisms to influence shopper behavior in brick & mortar and online retail environments. The academic literature is replete with work on what factors of ISM influence shopper behavior. In this chapter, we categorize prominent streams of findings on ISM into firm, customer, competitor and product characteristics of ISM and examine how the notion of a “store” is evolving from bricks to clicks – namely from physical formats to online shopping experiences. Insights from this chapter will help retailers and store managers identify what their customers respond to within a physical store, how technology is changing the way they can capture information on customers, and how shopper behavior is evolving in response to brick & mortar and online retail environments.

This paper aims to propose an enhanced static model of commercial braided pneumatic artificial muscles (PAMs), which is fully analytical without the need for experimentally determined parameters.

To address the highly nonlinear issues of PAMs, the enhanced model is derived considering the irregular shapes close to their end-fittings, as well as the elastic energy stored in both their braids and rubber bladders. The hysteresis characteristics of PAMs are also explored by analyzing the friction in the crossovers of the interlacing braided strands, together with that between the strands and their surrounding bladders. The isobaric and isometric experiments of a commercial PAM are conducted to demonstrate the enhancement, and the model accuracy is evaluated and compared with some existing models in terms of root mean square errors (RMSEs). Additionally, the proposed model is simplified to facilitate the applications that entail high computational efficiency.

The proposed model agrees well with the experimental results, which indicates its viability to accurately predict the static behaviors. An overall RMSE of 5.24 N shows that the enhanced model is capable of providing higher accuracy than the existing analytical models, while keeping the modeling cost at a minimum.

The proposed model, taking account of non-cylindrical shapes, elastic energy and friction, succeeds in enhancing the static predictions of commercial PAMs. The fully analytical model may accelerate the development of novel PAM-based robots for high-precision control, while giving a deeper understanding of commercial PAMs.

Multimedia applications such as digital audio and video have stringent quality of service (QoS) requirement in mobile ad hoc network. To support wide range of QoS, complex routing protocols with multiple QoS constraints are necessary. In QoS routing, the basic problem is to find a path that satisfies multiple QoS constraints. Moreover, mobility, congestion and packet loss in dynamic topology of network also leads to QoS performance degradation of protocol.

In this paper, the authors proposed a multi-path selection scheme for QoS aware routing in mobile ad hoc network based on fractional cuckoo search algorithm (FCS-MQARP). Here, multiple QoS constraints energy, link life time, distance and delay are considered for path selection.

The experimentation of proposed FCS-MQARP is performed over existing QoS aware routing protocols AOMDV, MMQARP, CS-MQARP using measures such as normalized delay, energy and throughput. The extensive simulation study of the proposed FCS-based multipath selection shows that the proposed QoS aware routing protocol performs better than the existing routing protocol with maximal energy of 99.1501 and minimal delay of 0.0554.

This paper presents a hybrid optimization algorithm called the FCS algorithm for the multi-path selection. Also, a new fitness function is developed by considering the QoS constraints such as energy, link life time, distance and delay.