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1 – 10 of over 172000
Article
Publication date: 17 April 2007

Yi Lin

This paper aims to show that systemic methods and thinking can be used to develop useful tools to address problems open in traditional science, such as Newtonian physics…

Abstract

Purpose

This paper aims to show that systemic methods and thinking can be used to develop useful tools to address problems open in traditional science, such as Newtonian physics, universal gravitation, planetary motions, and the three‐body problem.

Design/methodology/approach

Expanded on the yoyo model introduced earlier for general systems, a new figurative analysis method is introduced in this paper.

Findings

After establishing its theoretical and empirical foundations, this method is used to generalize Newton's laws of mechanics by addressing several unsettled problems in the history. Through the concept of equal quantitative effects, it is argued that this new method possesses some strength not found in pure quantitative methods. After studying the characteristics of whole evolutions of converging and diverging fluid motions, the concept of time is revisited using the new model. As further applications of the new method, one covers Kepler's laws of planetary motion, Newton's law of universal gravitation, and explains why planets travel along elliptical orbits, why no external forces are needed for systems to revolve about one another, and why binary star systems, tri‐nary star systems, and even n‐nary star systems can exist, for any natural number n≥2. By checking the study of the three‐body problem, a brand new method is provided to analyze the movement of three stars, visible or invisible. At the end, some open problems are cast for future research.

Originality/value

This paper shows for the first time in history that several well‐established laws in physics can be generalized using systemic thinking. Beyond that, an operative method of analysis is introduced to investigate problems that have been extremely difficult to handle in the scientific history. With adequate quantitative tools developed to accompany this method, it can be reasonably expected that an active systemic scientific era with a slightly different tilt from the contemporary science will follow shortly.

Details

Kybernetes, vol. 36 no. 3/4
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 June 2000

A. Savini

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community…

1131

Abstract

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 19 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 8 November 2022

Qi Yao, Xiaofang Tao and Wenkai Zhou

This study aims to empirically investigate how the interaction effect of occasion-setting cues and consumers’ cognitive styles (e.g. field dependence levels) influences their food…

Abstract

Purpose

This study aims to empirically investigate how the interaction effect of occasion-setting cues and consumers’ cognitive styles (e.g. field dependence levels) influences their food intake intention.

Design/methodology/approach

In this research, several scenario simulation studies were conducted to verify the hypotheses. A total of 646 participants were recruited for the experiments, and samples were obtained through well-established online research platforms.

Findings

In the occasion-setting cue advertisement condition, field-dependent (vs field-independent) consumers displayed increased cravings for food and purchase intention, with mental simulation playing a mediating role and cognitive load playing a moderating role.

Research limitations/implications

The influence of others (e.g. servers and other consumers) was not taken into consideration in this study. Future research can extend this study by conducting field experiments.

Practical implications

The research conclusions can help various organisations reduce consumers’ food overconsumption intention and encourage healthier food choices by adjusting occasion-setting cues in marketing stimuli and identifying the target consumers’ cognitive styles.

Originality/value

Based on embodied cognition theory, this study reveals the influence and internal mechanism of the interaction effect between occasion-setting cues and individual cognitive style on eating desire.

Details

European Journal of Marketing, vol. 56 no. 11
Type: Research Article
ISSN: 0309-0566

Keywords

Article
Publication date: 28 December 2020

Suwimon Saneewong Na Ayuttaya

This study aims to present a numerical analysis of the behavior of the electric field and flow field characteristics under electrohydrodynamics (EHD) force. The influence of the…

Abstract

Purpose

This study aims to present a numerical analysis of the behavior of the electric field and flow field characteristics under electrohydrodynamics (EHD) force. The influence of the jet airflow under the EHD force is investigated when it impacts the inclined flat plate.

Design/methodology/approach

The high electrical voltage and angle of an inclined flat plate are tested in a range of 0–30 kV and 0–90°, respectively. In this condition, the air is set in a porous medium and the inlet jet airflow is varied from 0–2 m/s.

Findings

The results of this study show that the electric field line patterns increase with increasing the electrical voltage and it affects the electric force increasing. The angle of inclined flat plate and the boundary of the computational model are influenced by the electric field line patterns and electrical voltage surface. The electric field pattern is the difference in the fluid flow pattern. The fluid flow is more expanded and more concentrated with increasing the angle of an inclined flat plate, the electrical voltage and the inlet jet airflow. The velocity field ratio is increased with increasing the electrical voltage but it is decreased with increasing the angle of the inclined flat plate and the inlet jet airflow.

Originality/value

The maximum Reynolds number, the maximum velocity field and the maximum cell Reynolds number are increased with increasing the electrical voltage, the inlet jet airflow and the angle of the inclined flat plate. In addition, the cell Reynolds number characteristics are more concentrated and more expanded with increasing the electrical voltage. The pattern of numerical results from the cell Reynolds number characteristics is similar to the pattern of the fluid flow characteristics. Finally, a similar trend of the maximum velocity field has appeared for experimental and numerical results so both techniques are in good agreement.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 12 September 2023

Takia Ahmed J. Al-Griffi and Abdul-Sattar J. Ali Al-Saif

The purpose of this study is to analyze the two-dimensional blood flow in the artery slant from the axis at an angle with mild stenosis under the joint effects of the…

Abstract

Purpose

The purpose of this study is to analyze the two-dimensional blood flow in the artery slant from the axis at an angle with mild stenosis under the joint effects of the electro-osmotic, magnetic field, chemical reaction and porosity using a new analytical method. In addition, the mathematical model presented by the researchers Tripathi and Sharma (2018c) was successfully developed by adding the effect of electro-osmosis and studying the impact of the new addition in the developed model on blood flow.

Design/methodology/approach

A new analytical method was used to find the analytical approximate solutions of two-dimensional blood flow in artery slant from the axis at an angle with mild stenosis. This technique is based on integrating the Akbari-Ganji and the homotopy perturbation methods.

Findings

The results of axial velocity, concentration, temperature and the wall shear stress for blood flow were analyzed in the cases of the absence and presence of electro-osmosis. Furthermore, in these two states of electro-osmosis, a contour plot was created to show the difference in the profile of velocity to the flow of blood when the magnetic field was increased and the altitude of stenosis was increased. The results showed that the new technique is effective and has high accuracy to determine the analytical approximate solutions of two-dimensional blood flow in artery slant from the axis at an angle with mild stenosis. The validity, utility and necessity of the new method were illustrated from the graphs of the new solutions; in addition, there is an excellent agreement with the results of previous studies.

Originality/value

This paper focuses on developing the mathematical model which was presented by the researchers Tripathi and Sharma (2018c), by adding the effect of the electro-osmosis to it, which has been successfully developed. According to the authors’ modest information, the new system has not been studied before. This current problem is solved by using an innovative approach known as the Akbari-Ganji homotopy perturbation method (AGHPM) which has not been used before in two cases: the presence and absence of the effect of electro-osmosis. This new technique afford new with effective and has high accuracy results. Furthermore, the new study (i.e. adding effect of electro-osmosis) with the applications of (variable viscosity, magnetic field, chemical reaction and porosity) illustrated the importance of applying electro-osmosis and how doctors can benefit from it during surgeries through proper use.

Article
Publication date: 1 November 1998

Stéphane Perrin and Philippe Boisse

An extension of the concept of error on constitutive relation is proposed to the case of Mindlin plate finite element computations. The error of the performed analysis is…

Abstract

An extension of the concept of error on constitutive relation is proposed to the case of Mindlin plate finite element computations. The error of the performed analysis is estimated from the incompatibility in relation with the constitutive equation of admissible fields calculated from the finite element results. In a first stage, loads and moments densities leading to the equilibrium of each element are computed on the element edges as the sums of densities derived from the finite element solution and of densities with a resultant equal to zero on each element edge. Then strictly statically admissible stress resultants are calculated within each element. Both of the two stages allow an optimization for the statically admissible field in order to get a more accurate error. The calculations are local which is very interesting especially in case of complex structure analyses with a large number of degrees of freedom for which adaptivity is an important feature. A set of examples shows the efficiency of the proposed estimator and the good adaptation of the error on constitutive law method to Mindlin plate analysis.

Details

Engineering Computations, vol. 15 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 8 January 2024

Anup Kumar, Bhupendra Kumar Sharma, Bandar Bin-Mohsen and Unai Fernandez-Gamiz

A parabolic trough solar collector is an advanced concentrated solar power technology that significantly captures radiant energy. Solar power will help different sectors reach…

Abstract

Purpose

A parabolic trough solar collector is an advanced concentrated solar power technology that significantly captures radiant energy. Solar power will help different sectors reach their energy needs in areas where traditional fuels are in use. This study aims to examine the sensitivity analysis for optimizing the heat transfer and entropy generation in the Jeffrey magnetohydrodynamic hybrid nanofluid flow under the influence of motile gyrotactic microorganisms with solar radiation in the parabolic trough solar collectors. The influences of viscous dissipation and Ohmic heating are also considered in this investigation.

Design/methodology/approach

Governing partial differential equations are derived via boundary layer assumptions and nondimensionalized with the help of suitable similarity transformations. The resulting higher-order coupled ordinary differential equations are numerically investigated using the Runga-Kutta fourth-order numerical approach with the shooting technique in the computational MATLAB tool.

Findings

The numerical outcomes of influential parameters are presented graphically for velocity, temperature, entropy generation, Bejan number, drag coefficient and Nusselt number. It is observed that escalating the values of melting heat parameter and the Prandl number enhances the Nusselt number, while reverse effect is observed with an enhancement in the magnetic field parameter and bioconvection Lewis number. Increasing the magnetic field and bioconvection diffusion parameter improves the entropy and Bejan number.

Originality/value

Nanotechnology has captured the interest of researchers due to its engrossing performance and wide range of applications in heat transfer and solar energy storage. There are numerous advantages of hybrid nanofluids over traditional heat transfer fluids. In addition, the upswing suspension of the motile gyrotactic microorganisms improves the hybrid nanofluid stability, enhancing the performance of the solar collector. The use of solar energy reduces the industry’s dependency on fossil fuels.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 23 October 2023

Gorakh Nath and Abhay Maurya

The purpose of the present article is to obtain the similarity solution for the shock wave generated by a piston propagating in a self-gravitating nonideal gas under the impact of…

Abstract

Purpose

The purpose of the present article is to obtain the similarity solution for the shock wave generated by a piston propagating in a self-gravitating nonideal gas under the impact of azimuthal magnetic field for adiabatic and isothermal flows.

Design/methodology/approach

The Lie group theoretic method given by Sophus Lie is used to obtain the similarity solution in the present article.

Findings

Similarity solution with exponential law shock path is obtained for both ideal and nonideal gas cases. The effects on the flow variables, density ratio at the shock front and shock strength by the variation of the shock Cowling number, adiabatic index of the gas, gravitational parameter and nonidealness parameter are investigated. The shock strength decreases with an increase in the shock Cowling number, nonidealness parameter and adiabatic index, whereas the strength of the shock wave increases with an increase in gravitational parameter.

Originality/value

Propagation of shock wave with spherical geometry in a self-gravitating nonideal gas under the impact of azimuthal magnetic field for adiabatic and isothermal flows has not been studied by any author using the Lie group theoretic method.

Details

Engineering Computations, vol. 40 no. 9/10
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 7 June 2021

Pascalin Tiam Kapen, Cédric Gervais Njingang Ketchate, Didier Fokwa and Ghislain Tchuen

For this purpose, a linear stability analysis based on the Navier–Stokes and Maxwell equations is made leading to an eigenvalue differential equation of the modified…

Abstract

Purpose

For this purpose, a linear stability analysis based on the Navier–Stokes and Maxwell equations is made leading to an eigenvalue differential equation of the modified Orr–Sommerfeld type which is solved numerically by the spectral collocation method based on Chebyshev polynomials. Unlike previous studies, blood is considered as a non-Newtonian fluid. The effects of various parameters such as volume fraction of nanoparticles, Casson parameter, Darcy number, Hartmann number on flow stability were examined and presented. This paper aims to investigate a linear stability analysis of non-Newtonian blood flow with magnetic nanoparticles with an application to controlled drug delivery.

Design/methodology/approach

Targeted delivery of therapeutic agents such as stem cells and drugs using magnetic nanoparticles with the help of external magnetic fields is an emerging treatment modality for many diseases. To this end, controlling the movement of nanoparticles in the human body is of great importance. This study investigates controlled drug delivery by using magnetic nanoparticles in a porous artery under the influence of a magnetic field.

Findings

It was found the following: the Casson parameter affects the stability of the flow by amplifying the amplitude of the disturbance which reflects its destabilizing effect. It emerges from this study that the taking into account of the non-Newtonian character is essential in the modeling of such a system, and that the results can be very different from those obtained by supposing that the blood is a Newtonian fluid. The presence of iron oxide nanoparticles in the blood increases the inertia of the fluid, which dampens the disturbances. The Strouhal number has a stabilizing effect on the flow which makes it possible to say that the oscillating circulation mechanisms dampen the disturbances. The Darcy number affects the stability of the flow and has a stabilizing effect, which makes it possible to increase the contact surface between the nanoparticles and the fluid allowing very high heat transfer rates to be obtained. It also emerges from this study that the presence of the porosity prevents the sedimentation of the nanoparticles. By studying the effect of the magnetic field on the stability of the flow, it is observed that the Hartmann number keeps the flow completely stable. This allows saying that the magnetic field makes the dissipations very important because the kinetic energy of the electrically conductive ferrofluid is absorbed by the Lorentz force.

Originality/value

The originality of this paper resides on the application of the linear stability analysis for controlled drug delivery.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 10 April 2018

G.P. Ashwinkumar, C. Sulochana and S.P. Samrat

The purpose of this paper is to investigate the momentum, heat and mass transfer characteristics of magnetic-nanofluid flow past a vertical plate embedded in a porous medium…

Abstract

Purpose

The purpose of this paper is to investigate the momentum, heat and mass transfer characteristics of magnetic-nanofluid flow past a vertical plate embedded in a porous medium filled with ferrous nanoparticles. The analysis is carried out in the presence of pertinent physical parameters such as aligned magnetic field, thermal radiation, chemical reaction, radiation absorption, heat source/sink.

Design/methodology/approach

The flow governing PDEs are transformed into ODEs using appropriate conversions. Further, the set of ODEs is solved analytically using the perturbation technique. The flow quantities such as velocity, thermal and concentration fields are discussed under the influence of above-mentioned pertinent physical parameters with the assistance of graphical depictions. Moreover, the friction factor, local Nusselt and Sherwood number are discussed in tabular form.

Findings

The results indicate that flow and thermal transport phenomenon is more effective in the case of the aligned magnetic field as compared with the transverse magnetic field. Also, the nanoparticle volume fraction plays a vital role in controlling the wall friction and heat transfer performance. The validation of the obtained results is done by comparing them with the results of various numerical techniques, and hence found them in excellent agreement.

Originality/value

In present days, the external magnetic fields are very effective to set the thermal and physical properties of magnetic-nanofluids and regulate the flow and heat transfer characteristics. The strength of the applied magnetic field affects the thermal conductivity of magnetic-nanofluids and makes it aeolotropic. With this incentive, the authors investigated the flow and heat transfer characteristics of electrically conducting magnetic-nanofluids over a vertical surface embedded in a porous medium. The authors discussed the dual nature of ferrous-water nanofluid in the presence of aligned magnetic field and transverse magnetic field cases. The influence of several physical parameters on velocity, thermal and concentration field converses with the succour of graphs.

Details

Multidiscipline Modeling in Materials and Structures, vol. 14 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

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