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Contemporary resurgence of interest in human capital has both analytic and empirical origins. Analysis has increasingly emphasised the need to consider both stocks and flows; in principle, every good is a capital good and labour is no exception. Modern theories of consumer behaviour, with their stress on long‐term planning particularise this viewpoint. These same theories have suggested the relevance of income distribution data for the explanation of consumer behaviour, the data have lent support, and together they have suggested that the process is reciprocal. Consumer behaviour and analysis should help in the spelling out of theories capable of explaining evolving patterns in income distributions.

Those who would become economists today have the choice of two ideologies, the one maintaining that the inner laws of the capitalist system are equilibrating and maximizing; the other, that they doom that system to self‐destruction. In the natural sciences, a theory is ‘a hypothesis that has been confirmed or established by observation or experiment, and is propounded or accepted as accounting for the known facts.’ (Third definition in the Shorter OED.) By contrast, in economics it is used, ‘In loose or general sense: A hypothesis proposed as an explanation; hence, a mere hypothesis, speculation, conjecture; an idea or set of ideas about something …’ (OED fifth definition).

Not everyone will accept the validity of the statement made by G. Routh in the first number of the International Journal of Social Economics that:

In this contribution to the growing discussion of the meaning, method‐dology and rationale of the socio‐economic approach we shall not reiterate the historical development of Social Economics but will concentrate on trying to stimulate discussion of the following questions:

It will be argued here that the need for anti‐discrimination policies in the labour market — while patently obvious to the present audience — can also be reinforced via an analytical approach, which we have elsewhere described as a “socio‐economic systems” approach. Briefly, such an approach leads to the conclusion that in most areas of social economics (including discrimination) we should be concerned with the study of the structure and processes of the dynamic field of societal relations within a complex and interdependent environment of many systems (social, economic, legal, political, historical, psychological, technological and natural). Consequently, we need to study these environmental systems, the elements of the structure, the process of adaptation of these structural elements to their environment, the accommodation and conflict generated by these processes, the societal relations stemming from these reactions and the feedback mechanisms whereby the open and dynamic system constantly adjusts (Figure 1).

The purpose of this paper is to present efficient and stable generalized auxiliary differential equation finite difference time domain (G-ADE-FDTD) implementation of graphene dispersion.

A generalized dispersive model is used for describing the graphene’s intraband and interband conductivities in the terahertz and infrared frequencies. In addition, the von Neumann method combined with the Routh-Hurwitz criterion are used for studying the stability of the given implementation.

The presented G-ADE-FDTD implementation allows modeling graphene’s dispersion using the minimal number of additional auxiliary variables, which will reduce both the CPU time and memory storage requirements. In addition, the stability of the implementation retains the standard non-dispersive Courant–Friedrichs–Lewy (CFL) constraint.

The given implementation is conveniently applicable for most commonly used dispersive models, such as Debye, Lorentz, complex-conjugate pole residue, etc.

The presented G-ADE-FDTD implementation not only unifies the implementation of both graphene’s intraband and interband conductivities, with the minimal computational requirements but also retains the standard non-dispersive CFL time step stability constraint.

In a harmonic drive during assembly of its components like strain wave generating (SWG) cam, flexspline (FS) and circular spline, a gap is formed between the cam’s outer surface and the FS cup inner surface due to mismatching. This gap, which is known as “Coning”, plays a vital role in the flow of lubricant at that interface. This paper aims to analyse the coning phenomenon and the lubrication mechanism.

In the present investigation, the geometry of the coning gap and its variation with the SWG cam rotation are established. Essentially, the deflection of FS cup and deformation of SWG cam (bearing outer race) are derived to find the gap due to coning. Next, the hydrodynamic lubrication equation is solved to get pressure profiles for this gap under suitable boundary conditions assuming non-Newtonian lubrication.

Methods of estimating the coning gap and lubrication pressure profiles are established. Effects of non-Newtonian terms (coupling number and non-dimentionalized characteristic length) and SWG length (finite, long and short) on pressure profiles are also shown. All analyses are done in non-dimensionalized form.

Establishing the geometry of coning and non-Newtonian hydrodynamic lubrication aspects in the coning in the FS cup and SWG cam interface are the originality of the present investigation.

The purpose of this paper is to present a new system frequency response model with participation of wind-hydro-thermal units to overcome frequency deviations.

The extracted minimum frequency equation is considered as a constraint in security-constrained unit commitment calculations. Because of high-order polynomials in the frequency transfer function and high degree of nonlinearity of minimum frequency constraint, Routh stability criterion method and piecewise linearization technique are used to reduce system order and linearize the system frequency response model, respectively.

The results of this paper indicate that by using this model, the hourly minimum frequency is improved and is kept within defined range.

This combined model can be used to evaluate the frequency of the power system following unexpected load increase or generation disturbances. It also can be used to investigate the system frequency performance and ensure power system security which are caused by peak load or loss of generation in presence of renewable energies.

If an algebraic polynomial equation has roots which are negative if real and have negative real parts if complex, the coefficients must satisfy certain fundamental conditions originally formulated by Routh. These conditions are here derived by comparatively simple algebra for the sextic equation by a method which can be generalized; its extension to equations of the eighth and tenth degree is indicated. The case of damped Lagrangian frequency equations is considered as an appropriate epilogue.