Search results

Households suffering from poverty often rely on parental migration and/or paid child labour for survival. The purpose of this paper is to investigate the effects of parental migration on paid child labour and human capital formation in a dynamic context, explicitly taking the effects of parental migration on child’s school and home education into account.

The author utilises a mathematical method. In particular, an overlapping-generations model is built, with agents who have a two-period life. The amount of paid child labour is determined as a solution of the utility maximisation problem.

Contrary to intuition, parental migration possibilities do not necessarily reduce paid child labour. In addition, parental migration possibilities do not necessarily raise human capital. Moreover, a trade-off might exist between alleviating paid child labour and raising human capital under parental migration possibilities.

Migration possibilities are given exogenously evenly among potential migrants by the foreign country. However, in general, they depend on potential migrants’ human capital so that migration possibilities differ across agents.

Migration is usually considered effective in alleviating poverty. However, since it does not necessarily reduce paid child labour and raise human capital, migration should be regulated in some cases as a means to escape from poverty.

This paper deals with parental migration and paid child labour in an identical dynamic model. This paper assumes that human capital is built not only by school education but also home education, the amount of which changes with the duration of parental migration.

THE highest strength wrought aluminium alloys currently available are based on the aluminium‐zinc‐magnesium‐copper system, and such alloys offer considerable potential for weight savings in airframe structures. However, these alloys have presented problems in service, arising from deficiencies in fracture toughness and fatigue crack propagation resistance together with a susceptibility to exfoliation corrosion and stress‐corrosion, which have led to restrictions being placed on their use by individual aircraft companies and by procurement authorities in a number of countries. This situation has led to the wide‐spread use in the UK and continental Europe of lower strength alloys of the aluminium‐copper‐magnesium‐silicon type, even though significant weight penalties are incurred in the process. There has been a more general acceptance of the high strength aluminium‐zinc‐magnesium‐copper alloys in the USA, where problems associated with their use have been partially alleviated by a willingness to replace components at short intervals, but even so during recent years a trend has developed there towards the use of lower strength versions of these alloys in attempts to improve airframe durability and reliability.

I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep current rise when an acceptor density in the i‐layer is high. It is shown that an optimum acceptor density exists to keep a good isolation. Photoconduction transients of GaAs n‐i‐n structures are also simulated, and are shown to be strongly affected by existence of n‐i junctions.

To investigate the potential of raising the retirement age and reforming pension insurance in mitigating intra- and inter-generational income inequality, thereby offering empirical support for governmental policy formulation.

A dynamic general equilibrium model with intertemporal iteration is developed to comprehensively assess the impact of policies raising the retirement age on income inequality, taking into account delayed retirement, survival probability, and pension insurance. The theoretical hypotheses are validated through simulation using MATLAB.

Through theoretical analysis, it is determined that, given certain assumptions are satisfied, raising the retirement age can effectively mitigate intra-generational income inequality, inter-generational income inequality under both the pay-as-you-go and fund accumulation systems. Simulation results indicate that, under current parameter settings, raising the retirement age can reduce the Gini coefficient. Furthermore, this study reveals that regardless of the pay-as-you-go or fund accumulation system, pension insurance serves as a mechanism for income redistribution and alleviating income inequality.

It offers a theoretical foundation for the government's policy on delayed retirement and endowment insurance.

Draws on data from the 1989 Bangladesh Fertility Survey to explore whether or not socio‐demographic factors such as woman’s age, education, occupation, income and residence affect fertility because of different attitudes towards decision making and the use of contraception. Describes the methodology used and forms of data analysis – path modelling via LISREL. Analyses the findings – that as the woman’s age increases so does the number of children ever born, women who have not completed primary education have more children than women who have completed secondary or higher education, urban women have fewer children than rural women, and women with more education and a higher income have more autonomy in decision making, consequently are more likely to use contraception and have fewer children. Reports that when men make the decisions, families are larger and infers that there are policy implications in that finding. Concludes that the determining factors affecting fertility and use of contraception in Bangladesh are the woman’s level of education, residence in urban or rural areas, and the extent of inter‐spouse communication.

This study aims to explore the combined impacts of velocity and thermal slips on hybrid nanomaterial (GO+Ag+kerosene oil) bounded between two parallel infinite walls (plates). Both the walls are separated by a distance. The upper wall is subjected to squeezing with velocity, while the lower wall stretches with velocity. A uniform magnetic field acts normally to the flow. Moreover, heat transmission is analyzed in the presence of Joule heating. Heat transport characteristics are investigated by imposing the Cattaneo–Christov (C–C) heat flux model. The behavior of velocities, skin friction and temperature under sundry variables are examined graphically.

The obtained partial differential equations (PDEs) related to the considered problem are nondimensionalized by choosing appropriated variables. These nondimensional PDEs are then solved by the numerical technique, finite difference method (FDM). For implementation of this method, the obtained nondimensional PDEs are converted into finite difference equations (FDEs) using forward difference (FD) toolkits.

Velocity of the hybrid nanomaterial decreases with higher Hartman number and velocity slip parameter, while it increases with increase in Reynolds and squeezing numbers. Temperature of the hybrid nanomaterial increases for large Hartman number, Eckert number and squeezing parameter, while it is reduced by higher thermal slip parameter, thermal relaxation time parameter and nanoparticle volume fractions for graphene oxide (GO) and silver (Ag). Skin friction is controlled through higher Reynolds number, while it intensifies with nanoparticle volume fractions for GO and Ag.

Here, the authors have investigated 2D flow of hybrid nanomaterial bounded between two parallel walls. The lower and upper walls are subjected to stretching and squeezing, respectively. The authors guarantee that all outcomes and numerical technique (FDM) results are original, neither submitted nor published in any journal before.

ABOUT two years ago—early in 1928—rumours first began to circulate that the Packard Company had built a successful air‐cooled radial Diesel engine which had satisfactorily completed flight tests.

To improve the deficiencies of the existing journal influencing evaluation indexes, which have single influencing factors and are greatly affected by the number of papers published, this paper proposes a new evaluation of the journal influence method based on the RA index.

In the metrics create, the paper introduces the RA index for evaluating the impact of authors and analyzing its feasibility in journal evaluation. Then the RA index is divided by the number of journal's published papers to obtain the RAQ index to evaluate journal impact. In the metrics analysis, the authors analyze the statistical characteristics of the RAQ index using statistical analysis, and t-test, Roc curve and PLS were used to analyze the relationship between the RAQ index and other indicators.

Empirical results show that the RAQ index can effectively identify high-quality journals and reduce the number of published papers on journal evaluation. The empirical results show that the RAQ index has higher stability and discrimination than the h-index and g-index. Compared with other indexes, the RAQ index has better evaluation effects and statistical characteristics.

The current study proposes journals' RAQ index, which integrates the influence of high-, low- and zero-cited papers. It solves the problem of the virtual high of the h-type index. The findings will contribute to the evaluation of journal influence by offering a new research idea that facilitates the fairness and rationality of journal evaluation.

Hybrid nanofluids are more effective in the enhancement of heat transfer than mono nanofluids. The mono nanofluid’s thermophysical properties are limited, so it is not enough to succeed in the required thermal performance. The Darcy–Forchheimer hybrid nanofluid flow based on Ag and TiO2 has been used for the applications of drug delivery. In photoelectrochemical (PEC) biosensing applications, the detection of targets has been greatly enhanced by the use of various TiO2 nanostructures. Biosensors, drug delivery systems and medical devices can benefit greatly from the combination of Ag and TiO2.

The Ag and TiO2 hybrid nanofluid flow in an inclined squeezing channel is considered for the applications of drug delivery. The channel walls are permeable and allow fluid in the form of suction and injection, while the flow medium inside the channel is also nonlinearly porous. A set of nonlinear differential equations is created from the main governing equations. The model problem is solved by using the artificial neural network (ANN), and the results are plotted and discussed. Recent and past results have been observed to have a strong correlation.

It can be concluded that the contracted and expanding parameter nature is the main factor in controlling hybrid nanofluid flow in the inclined squeezing flow. The values of the other parameters vary the profile’s growth. The central zone has the lowest absolute value of normal pressure drop for the pair of cases with positive or negative Reynolds. The lower heated wall becomes more efficient when the increase is used with a 5% volume fraction. The lower wall has an increasing percentage of 6.9% and 9.75% when using nanofluid and hybrid nanofluid, respectively.

The authors believe that no one has ever investigated the Darci–Forchheimer flow in a squeezing inclined channel for medical applications. The physical properties of the Ag and TiO2 hybrid nanofluid make it suitable for use as a medication in the biomedical field. The ANN is also a novel approach to solving the current problem. This research is focused on stabilizing hybrid nanofluid flow in the squeezing and porous channels by optimizing normal pressure under the influence of embedded parameters. This main part of the research is not usually mentioned in the existing literature.

Hybrid nanofluids can effectively utilize the antimicrobial properties of TiO2 and Ag nanomaterials for drug delivery applications due to their unique properties. Ag and TiO2 nanomaterials have the ability to control temperature distribution during the flow in an inclined channel, which is crucial for uniform drug delivery. Controlling the release rate of drugs and maintaining the flow stability is largely dependent upon the increase in temperature. The Ag and TiO2 nanoparticles are effective in localized hyperthermia treatments, and this procedure necessitates a temperature higher than the body’s temperature. Therefore, increasing the temperature profile is essential for drug delivery.

Hybrid nanofluids can effectively utilize the antimicrobial properties of TiO2 and Ag nanomaterials for drug delivery applications due to their unique properties. Ag and TiO2 nanomaterials have the ability to control temperature distribution during the flow in an inclined channel, which is crucial for uniform drug delivery. Controlling the release rate of drugs and maintaining the flow stability is largely dependent upon the increase in temperature. The Ag and TiO2 nanoparticles are effective in localized hyperthermia treatments, and this procedure necessitates a temperature higher than the body’s temperature. Therefore, increasing the temperature profile is essential for drug delivery.

The authors believe that no one has ever investigated the Darci–Forchheimer flow in a squeezing channel for medical applications. Moreover, the walls of the channel and the flow medium are both porous. The physical properties of the Ag and TiO2 hybrid nanofluid make it suitable for use as a medication in the biomedical field. The idea of a hybrid nanofluid flow in a squeeze channel using blood-based Ag and TiO2 is also new and important for drug delivery applications. The ANN is also a novel approach to solving the current problem.

From earliest times the land and all it produced to feed and sustain those who dwelt on it was mankind's greatest asset. From the Biblical “land of milk and honey”, down through history to the “country of farmers” visualised by the American colonists when they severed the links with the mother country, those who had all their needs met by the land were blessed — they still are! The inevitable change brought about by the fast‐growing populations caused them to turn to industry; Britain introduced the “machine age” to the world; the USA the concept of mass production — and the troubles and problems of man increased to the present chaos of to‐day. There remained areas which depended on an agri‐economy — the granary countries, as the vast open spaces of pre‐War Russia; now the great plains of North America, to supply grain for the bread of the peoples of the dense industrial conurbations, which no longer produced anything like enough to feed themselves.