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Article
Publication date: 23 September 2021

Najiyah Safwa Khashi'ie, Iskandar Waini, Syazwani Mohd Zokri, Abdul Rahman Mohd Kasim, Norihan Md Arifin and Ioan Pop

This paper aims to accentuate the behavior of second-grade hybrid Al2O3–Cu nanofluid flow and its thermal characteristics driven by a stretching/shrinking Riga plate.

Abstract

Purpose

This paper aims to accentuate the behavior of second-grade hybrid Al2O3–Cu nanofluid flow and its thermal characteristics driven by a stretching/shrinking Riga plate.

Design/methodology/approach

The second-grade fluid is considered with the combination of Cu and Al2O3 nanoparticles. Three base fluids namely water, ethylene glycol (EG) and methanol with different Prandtl number are also examined. The formulation of the mathematical model of second-grade hybrid nanofluid complies with the boundary layer approximations. The complexity of the governing model is reduced into a simpler differential equations using the similarity transformation. The bvp4c solver is fully used to solve the reduced equations. The observation of multiple solutions is conducted for the assisting (stretching) and opposing (shrinking) cases.

Findings

The impact of suction parameter, second-grade parameter, electromagnetohydrodynamics (EMHD) parameter, velocity ratio parameter and the volumetric concentration of the alumina and copper nanoparticles are numerically analyzed on the velocity and temperature profiles, skin friction coefficient and local Nusselt number (thermal rate) of the second-grade Al2O3–Cu/water. The solution is unique when (static and stretching cases) while dual for a specific range of negative in the presence of suction effect. Based on the appearance of the first solution in all cases of, it is physically showed that the first solution is stable. Further examination reveals that the EMHD and suction parameters are the contributing factors for the thermal enhancement of this non-Newtonian working fluid. Meanwhile, the viscosity of the non-Newtonian fluid also plays a significant role in the fluid motion and heat transfer rate based on the finding that the EG base fluid produces the maximum heat transfer rate but the lowest critical value and skin friction coefficient.

Originality/value

The results are novel and contribute to the discovery of the hybrid nanoparticles’ performance in the non-Newtonian second-grade fluid. Besides, this study is beneficial to the researchers in this field and general audience from industries regarding the factors, which contributing to the thermal enhancement of the working fluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 4 December 2023

Chandan Kumawat, Bhupendra Kumar Sharma, Taseer Muhammad and Liaqat Ali

The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past…

Abstract

Purpose

The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past couple of decades, the percentage of deaths associated with blood vessel diseases has risen sharply to nearly one third of all fatalities. For vascular disease to be stopped in its tracks, it is essential to understand the vascular geometry and blood flow within the artery. In recent scenarios, because of higher thermal properties and the ability to move across stenosis and tumor cells, nanoparticles are becoming a more common and effective approach in treating cardiovascular diseases and cancer cells.

Design/methodology/approach

The present mathematical study investigates the blood flow behavior in the overlapped stenosed curved artery with cylinder shape catheter. The induced magnetic field and entropy generation for blood flow in the presence of a heat source, magnetic field and nanoparticle (Fe3O4) have been analyzed numerically. Blood is considered in artery as two-phases: core and plasma region. Power-law fluid has been considered for core region fluid, whereas Newtonian fluid is considered in the plasma region. Strongly implicit Stone’s method has been considered to solve the system of nonlinear partial differential equations (PDE’s) with 10–6 tolerance error.

Findings

The influence of various parameters has been discussed graphically. This study concludes that arterial curvature increases the probability of atherosclerosis deposition, while using an external heating source flow temperature and entropy production. In addition, if the thermal treatment procedure is carried out inside a magnetic field, it will aid in controlling blood flow velocity.

Originality/value

The findings of this computational analysis hold great significance for clinical researchers and biologists, as they offer the ability to anticipate the occurrence of endothelial cell injury and plaque accumulation in curved arteries with specific wall shear stress patterns. Consequently, these insights may contribute to the potential alleviation of the severity of these illnesses. Furthermore, the application of nanoparticles and external heat sources in the discipline of blood circulation has potential in the medically healing of illness conditions such as stenosis, cancer cells and muscular discomfort through the usage of beneficial effects.

Details

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

Keywords

Article
Publication date: 13 March 2017

Mark Taylor and Denis Reilly

This paper aims to present the application of situation calculus for knowledge representation in missing persons investigations.

Abstract

Purpose

This paper aims to present the application of situation calculus for knowledge representation in missing persons investigations.

Design/methodology/approach

The development of a knowledge representation model for the missing persons investigation process based upon situation calculus, with a demonstration of the use of the model for a missing persons example case.

Findings

Situation calculus is valuable for knowledge representation for missing persons investigations, as such investigations have state changes over time, and due to the complexity of the differing investigation activities applicable to different situations, can be difficult to represent using simpler approaches such as tables or flowcharts.

Research limitations/implications

Situation calculus modelling for missing persons investigations adds formalism to the process beyond that which can be afforded by the current use of text, tables or flowcharts. The additional formalism is useful in dealing with the uncertainty present in such investigations.

Practical implications

The implications are a simplification of the application of the current police guidelines, and thoroughness in the application of such guidelines for missing persons investigations via situation calculus modelling.

Social implications

This paper supports the management of missing person investigations, by using the most critical variables in a missing persons investigation to determine relevant investigation and search activities applicable to the circumstances of a given case.

Originality/value

The novelty of the knowledge representation approach is the application of situation calculus via state and action vectors and a matrix of fluents to the process of missing persons investigations.

Details

Journal of Systems and Information Technology, vol. 19 no. 1/2
Type: Research Article
ISSN: 1328-7265

Keywords

Article
Publication date: 1 December 2006

Xuemou Wu

The purpose of this paper is to present an academic programme of pansystems research with a lot of new concepts, principles, methods. Universal consideration of…

1233

Abstract

Purpose

The purpose of this paper is to present an academic programme of pansystems research with a lot of new concepts, principles, methods. Universal consideration of philosophy‐mathematics‐technology is set forth with mega‐combination. The emphasis on the transfield internet‐like investigations is developed. Many theory‐methods of pansystems get further concise optimization.

Design/methodology/approach

The concrete contents of the paper include: historical megawave, philosophical stratagems, meta‐mathematics, meta‐methodology, technological realistic principles, unification and differentiation of encyclopedic branches, systems science, information theory, cybernetics, biosystems, generalized vitality, computer and IT, thinking science, logic, OR, AI, PR, DM, modernization of yinyang analysis combining dialectics, sociology, economics, meta‐relativity, generalized quantification and scale theory, general process of birth‐growth‐ageing‐disease‐death, the inheritance and development of 300 scholars' researches, etc.

Findings

All of the topics concerned with are reduced to the actualizations of PVOR – pansystems variational OR: Vd(xy)=*0*/PRR′P′/0**, which is an integrated synthesis of 20‐PanStemCells of PanConcepts and PanMethod, and embodies a specific pansystems summarization for the core of the true and the good. Furthermore, the formula “Pansystems Researches=*(PVOR/0**/Pan54787721/Everything)+*0*=*Pan–netlike connections of thoughts and methods” is expanded with concrete applications.

Originality/value

Provides information on pansystems research.

Details

Kybernetes, vol. 35 no. 10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 21 August 2007

Mohamed Saad Saleh, Abdullah Alrabiah and Saad Haj Bakry

With the widespread of e‐services, provided by different organizations at the internal intranet level, the business extranet level, and the public internet level, compliance with…

1013

Abstract

Purpose

With the widespread of e‐services, provided by different organizations at the internal intranet level, the business extranet level, and the public internet level, compliance with international information security management standards is becoming of increasing importance for establishing a common and safe environment for such services. The purpose of this paper is to examine the development of a mathematical model that enables the investigation of compliance of organizations with the widely acknowledged international information security management standard ISO 17799‐2005.

Design/methodology/approach

The model is based on the strategy, technology, organization, people and environment – STOPE – framework that provides an integrated well‐structured view of the various factors involved. The paper addresses the use of the model for practical investigations; it describes a practical example illustrating possible practical results.

Findings

The results show the strengths and the weaknesses of compliance, with the standard, at different levels: from the level of the measures associated with each of the “131” standard protection controls, up to the level of the STOPE domains.

Originality/value

The paper addresses the use of a mathematical model for practical investigations of compliance with the international information security management standard.

Details

Information Management & Computer Security, vol. 15 no. 4
Type: Research Article
ISSN: 0968-5227

Keywords

Article
Publication date: 1 July 2003

Xiaolong Wu, Dinghe Guo, Jinghong Pan and Xuemou Wu

In this paper, we will introduce charm pansystems and provide mathematical models for panweighted field‐network. Various mathematical models of pansystems will be discussed. Some…

Abstract

In this paper, we will introduce charm pansystems and provide mathematical models for panweighted field‐network. Various mathematical models of pansystems will be discussed. Some traditional mathematical concepts such as topology space and rough sets theory will be analyzed within this framework.

Details

Kybernetes, vol. 32 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 25 July 2019

Mehdi Bidabadi, Sadegh Sadeghi, Pedram Panahifar, Davood Toghraie and Alireza Rahbari

This study aims to present a basic mathematical model for investigating the structure of counter-flow non-premixed laminar flames propagating through uniformly-distributed organic…

Abstract

Purpose

This study aims to present a basic mathematical model for investigating the structure of counter-flow non-premixed laminar flames propagating through uniformly-distributed organic fuel particles considering preheat, drying, vaporization, reaction and oxidizer zones.

Design/methodology/approach

Lycopodium particles and air are taken as biofuel and oxidizer, respectively. Dimensionalized and non-dimensionalized forms of mass and energy conservation equations are derived for each zone taking into account proper boundary and jump conditions. Subsequently, to solve the governing equations, an asymptotic method is used. For validation purpose, results achieved from the present analysis are compared with reliable data reported in the literature under certain conditions.

Findings

With regard to the comparisons, although different complex non-homogeneous differential equations are solved in this paper, acceptable agreements are observed. Finally, the impacts of significant parameters including fuel and oxidizer Lewis numbers, equivalence ratio, mass particle concentration, fuel and oxidizer mass fractions and lycopodium initial temperature on the flame temperature, flame front position and flow strain rate are elaborately explained.

Originality/value

An asymptotic method for mathematical modeling of counter-flow non-premixed multi-zone laminar flames propagating through lycopodium particles.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 14 November 2008

George K. Stylios

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…

1250

Abstract

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 20 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 3 April 2023

Hongqiang Ma, Yue Xie, Xingpeng Song, Yu Liu, Xinmei Luo and Shengxun Wang

The purpose of this paper is to recover the waste heat of flue gas heat exchanger (FGHE) as efficiently as possible and avoid the acid dew corrosion of that.

Abstract

Purpose

The purpose of this paper is to recover the waste heat of flue gas heat exchanger (FGHE) as efficiently as possible and avoid the acid dew corrosion of that.

Design/methodology/approach

A novel flue gas waste heat recovery system was proposed in the paper. The dynamic mathematical models of key equipment in that were established based on theory and experiment method. The proportion integration differentiation-differentiation (PID-P) cascade control method based on particle swarm optimization algorithm was used to control the outlet temperature of FGHE. The dynamic characteristics of the flue gas heat exchange system were simulated by the particle swarm optimization algorithm with different fitness functions.

Findings

The PID-P temperature controller parameters can be quickly and effectively obtained by the particle swarm optimization algorithm based on the fitness function of integral time absolute error (ITAE). The overshoot, rise time and adjusting time of the novel system are 2, 83 and 105s, respectively. Compared with the traditional two-step tuning (T-ST) method, the novel system is better in dynamic and steady-state performance. The overshoot and the adjustment time of the system are reduced by 44% and 328s, respectively. ITAE is a performance evaluation index for control system with good engineering practicability and selectivity.

Originality/value

The dynamic mathematical model of key equipment in the new flue gas waste heat recovery system is established and the system's control strategies and methods are explored.

Details

Engineering Computations, vol. 40 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 13 November 2009

George K. Stylios

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…

1103

Abstract

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 21 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

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