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Recently, a new formulation has been introduced for non-local mechanics in terms of fractional calculus. Fractional calculus is a branch of mathematical analysis that studies the differential operators of an arbitrary (real or complex) order and is used successfully in various fields such as mathematics, science and engineering. The purpose of this paper is to introduce a new fractional non-local theory which may be applicable in various simple or complex mechanical problems.

In this paper (by using fractional calculus), a fractional non-local theory based on the conformable fractional derivative (CFD) definition is presented, which is a generalized form of the Eringen non-local theory (ENT). The theory contains two free parameters: the fractional parameter which controls the stress gradient order in the constitutive relation and could be an integer and a non-integer and the non-local parameter to consider the small-scale effect in the micron and the sub-micron scales. The non-linear governing equation is solved by the Galerkin and the parameter expansion methods. The non-linearity of the governing equation is due to the presence of von-Kármán non-linearity and CFD definition.

The theory has been used to study linear and non-linear free vibration of the simply-supported (S-S) and the clamped-free (C-F) nano beams and then the influence of the fractional and the non-local parameters has been shown on the linear and non-linear frequency ratio.

A new parameter of the theory (the fractional parameter) makes the modeling more fixable – this model can conclude all of integer and non-integer operators and is not limited to special operators such as ENT. In other words, it allows us to use more sophisticated mathematics to model physical phenomena. On the other hand, in the comparison of classic fractional non-local theory, the theory applicable in various simple or complex mechanical problems may be used because of simpler forms of the governing equation owing to the use of CFD definition.

Since the 1970s and 1980s, subsequent waves of so-called ‘new immigration’ have arrived in the United States and Europe. In the United States, this immigration started with the arrival of immigrants and asylum-seekers from Mexico, Central America and Asia. In Europe, the trend began with the influx of Turkish and Moroccan immigrants and continues today with the ongoing refugee crisis. Anti-immigrant politicians on both sides of the Atlantic have adopted exclusionary and often xenophobic rhetoric to further their policies, arguing that these new immigrants and their children cannot assimilate into Western society. A literature review reveals why the classical linear theory of second-generation assimilation is no longer relevant and proposes the contemporary segmented assimilation and comparative integration context theories developed by US and European researchers. A presentation of the findings of two state-of-the-art studies – the CILS project for the United States context and the TIES project for the European context – provides empirical evidence that, despite undeniable obstacles, the new second generation can assimilate into Western education systems and labour markets. Nonetheless, gaps in the existing literature also suggest the need for further research to create a more generalisable theory of second-generation assimilation before appropriate policy measures can be implemented.

The stability of linear time‐delay systems with point internal delays is difficult to deal with in practice because of the fact that their characteristic equation is usually of transcendent type rather than of polynomial type. This feature causes usually the system to possess an infinite number of poles. In this paper, stability tests for this class of systems are obtained either based on extensions of classical tests applicable to delay‐free systems or on approaches within the framework of two‐dimensional digital filters. Some of those two‐dimensional stability tests are also proved to be useful for stability testing of a common class of linear hybrid systems which involve coupled continuous and digital substates after a slight “ad‐hoc” adaptation of the tests for that situation.

This paper investigates how macroeconomic policy and planning of large‐scale dynamic systems are approached from the cybernetic principle, as can be viewed in the interplay of information, decision and control. Some speculations about directions in large‐scale policy and planning methods are offered.

Brief introduction on the importance and the need for plastic analysis methods were presented in the beginning section of this review. The plastic method for analysis was considered to be the more advanced method of analysis because of its ability to represent the true behaviour of the steel structures. Then in the following section, a literature analysis has been carried out on the previous investigations done on steel plates, steel beams and steel frames by other authors. The behaviour of them under different types of loading were presented and are under the investigation of innovative new analysis methods.

Structure member connections also have the potential for plastic failure. In this study, the authors have highlighted a few topics to be discussed. The three topics in this study are T-end plate connections to a square hollow section, semi-rigid connections and cold-formed steel storage racks with spine bracings using speed-lock connections. Connection is one of the important parts of a structure that ensures the integrity of the structure. Finally, in this technical paper, the authors introduce some topics related to seismic action. Application of the Theory of Plastic Mechanism Control in seismic design is studied in the beginning. At the end, its in-depth application for moment resisting frames-eccentrically braced frames dual systems is investigated.

When this study involves the design of a plastic structure, the design criteria must involve the ultimate load rather than the yield stress. As the steel behaves in the plastic range, it means the capacity of the steel has reached the ultimate load. Ultimate load design and load factor design are the methods in the range of plastic analysis. After the steel capacity has reached beyond the yield stress, it fulfills the requirement in this method. The plastic analysis method offers a consistent and logical approach to structural analysis. It provides an economical solution in terms of steel weight, as the sections designed using this method are smaller compared with elastic design methods.

The plastic method is the primary approach used in the analysis and design of statically indeterminate frame structures.

The purpose of this paper is to clarify the dynamic principle of internal structure of a complex morphing wing and control the wing to change configurations rapidly and smoothly. It includes modeling the dynamics of the morphing wing and designing a rational morphing control system.

The dynamic model of the morphing wing is developed based on Lagrange method of analytical mechanics. The generalized forces are obtained by virtual work principle. Since the morphing wing is a strongly coupled, over‐actuated and nonlinear system with multi‐input and multi‐output, the control system design includes a control allocator, a dynamic inversion controller and two PID controllers. The control allocator is designed based on pseudo inverse method; the dynamic inversion controller is applied to make the original system decoupled into two independent linear systems by proper nonlinear feedback transformation; two classical PID controllers are adopted for the linearlized systems.

The validity of the dynamic model and the controller is verified according to the simulation results using ADAMS and Matlab. It suggests that integrating Lagrange equation, pseudo inverse allocation, dynamic inversion control and classical PID method, is an effective way to solve problems of dynamic modeling and control for morphing wings.

The flexibility of the structure, the changes of the aerodynamic load, the mass and the dynamic performances of actuators are not taken into account. Therefore, researchers are encouraged to develop a more realistic morphing wing model.

The paper includes implications for the development of a dynamic model of a complex morphing wing and a rational morphing control system.

The paper fulfils a complete process from multi‐rigid‐body dynamic modeling to control system design for an over‐actuated nonlinear complex morphing wing, which could be a foundation of further researches on morphing wing dynamics and control.

An aerothermodynamic design code for axisymmetric projectiles has been developed using a viscous‐inviscid interaction scheme. Separate solution procedures for the inviscid and the viscous (boundary layer) fluid dynamic equations are coupled by an iterative solution procedure. Non‐equilibrium, equilibrium and perfect gas boundary layer equations are included. The non‐equilibrium gas boundary layer equations assume a binary mixture (two species; atoms and molecules) of chemically reacting perfect gases. Conservation equations for each species include finite reaction rates applicable to high temperature air. The equilibrium gas boundary layer equations assume infinite rate reactions, while the perfect gas equations assume no chemical reactions. Projectile near‐wall and surface flow profiles (velocity, pressure, density, temperature and heat transfer) representing converged solutions to both the inviscid and viscous equations can be obtained in less than two minutes on minicomputers. A technique for computing local reverse flow regions is included. Computations for yawed projectiles are accomplished using a coordinate system transformation technique that is valid for small angle‐of‐attack. Computed surface pressure, heat transfer rates and aerodynamic forces and moments for 1.25 &le Mach No. &le 10.5 are compared to wind tunnel and free flight measurements on flat plate, blunt‐cone, and projectile geometries such as a cone‐cylinder‐flare.

This study aims to propose an aerodynamic force decomposition which, for the first time, allows for thrust/drag bookkeeping in two-dimensional viscous and unsteady flows. Lamb vector-based far-field methods are used at the scope, and the paper starts with extending recent steady compressible formulas to the unsteady regime.

Exact vortical force formulas are derived considering inertial or non-inertial frames, viscous or inviscid flows, fixed or moving bodies. Numerical applications to a NACA0012 airfoil oscillating in pure plunging motion are illustrated, considering subsonic and transonic flow regimes. The total force accuracy and sensitivity to the control volume size is first analysed, then the axial force is decomposed and results are compared to the inviscid force (thrust) and to the steady force (drag).

Two total axial force decompositions in thrust and drag contributions are proposed, providing satisfactory results. An additional force decomposition is also formulated, which is independent of the arbitrary pole appearing in vortical formulas. Numerical inaccuracies encountered in inertial reference frames are eliminated, and the extended formulation also allows obtaining an accurate force prediction in presence of shock waves.

No thrust/drag bookkeeping methodology was actually available for oscillating airfoils in viscous and compressible flows.

This paper seeks to increase our understanding on the fluid mechanics and heat transfer in a transitional mixed convection flow between two vertical plates. Direct numerical simulation by the spectral method, with a weak formulation, is used to solve the transient 3–D Navier‐Stokes equations and energy equation. Initial disturbances consist of the finite‐amplitude 2–D Tollmien‐Schlichting wave and two 3–D oblique waves. The transition phenomena in a mixed‐convection flow can be significantly different from the isothermal flow. Disturbance competitions among different modes are also found to be different from those known for an isothermal flow. In a mixed‐convection flow, there exist thresholds for the low‐mode Fourier waves. The intensified vortices are concentrated left of the central surface between the two plates. Hairpin vortices are formed with high Ri. Based on the flow visualization, the λ vortices are found to be staggered on the surfaces parallel to the plates. The Ri number seems to be the main parameter governing the transition mechanism. The Nu number is found to increase during transition.