Mohammadhossein Hajiyan, Shohel Mahmud, Mohammad Biglarbegian, Hussein A. Abdullah and A. Chamkha
The purpose of this paper is to investigate the convective heat transfer of magnetic nanofluid (MNF) inside a square enclosure under uniform magnetic fields considering…
Abstract
Purpose
The purpose of this paper is to investigate the convective heat transfer of magnetic nanofluid (MNF) inside a square enclosure under uniform magnetic fields considering nonlinearity of magnetic field-dependent thermal conductivity.
Design/methodology/approach
The properties of the MNF (Fe3O4+kerosene) were described by polynomial functions of magnetic field-dependent thermal conductivity. The effect of the transverse magnetic field (0 < H < 105), Hartmann Number (0 < Ha < 60), Rayleigh number (10 <Ra <105) and the solid volume fraction (0 < φ < 4.7%) on the heat transfer performance inside the enclosed space was examined. Continuity, momentum and energy equations were solved using the finite element method.
Findings
The results show that the Nusselt number increases when the Rayleigh number increases. In contrast, the convective heat transfer rate decreases when the Hartmann number increases due to the strong magnetic field which suppresses the buoyancy force. Also, a significant improvement in the heat transfer rate is observed when the magnetic field is applied and φ = 4.7% (I = 11.90%, I = 16.73%, I = 10.07% and I = 12.70%).
Research limitations/implications
The present numerical study was carried out for a steady, laminar and two-dimensional flow inside the square enclosure. Also, properties of the MNF are assumed to be constant (except thermal conductivity) under magnetic field.
Practical implications
The results can be used in thermal storage and cooling of electronic devices such as lithium-ion batteries during charging and discharging processes.
Originality/value
The accuracy of results and heat transfer enhancement having magnetic field-field-dependent thermal conductivity are noticeable. The results can be used for different applications to improve the heat transfer rate and enhance the efficiency of a system.
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Hussein A. Abdullah and Chris R. Chatwin
The adoption of integrated computer‐based manufacturing and managementtechniques by small, traditional engineering companies often representsan unaffordable and high risk…
Abstract
The adoption of integrated computer‐based manufacturing and management techniques by small, traditional engineering companies often represents an unaffordable and high risk investment strategy in technology that is often not well understood by its recipients. Paradoxically, the opportunity for complete success in a small to medium‐sized enterprise (SME) is greater than in a large company which very often is incapable of full integration due to the divisions and inertia implicit in a large hierarchical organization. To derive full benefits from such an investment the company must possess a meticulous understanding of its market, fiscal environment, operations management, engineering and technological skills, manufacturing facilities and product range. It must adopt an appropriate implementation of CIM that does not debase previous ad hoc investments in what are often termed islands‐of‐automation or information technology. For success a well‐planned stepwise approach is vital. Reports on the approach adopted by a small to medium‐sized Scottish engineering company specializing in the production of mechanical actuation systems. Over a three‐year period the company embarked on a low‐cost, phased implementation of software and hardware systems that exploit a database to integrate its design, manufacturing the business operations. A major element in these systems is the distributed Command, Communication and Control (C3) environment which has transformed the effectiveness of operations. The company′s investments were based on a prudent assessment of its current and planned product range, existing and planned manufacturing facilities, the scale of its operations and business objectives.
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XinYing Chew, Raed Alharbi, Khai Wah Khaw and Alhamzah Alnoor
The study is interested in knowing “the role of the organizational structure as a mediating variable of the relationship between the information technology and organizational…
Abstract
Purpose
The study is interested in knowing “the role of the organizational structure as a mediating variable of the relationship between the information technology and organizational communication”.
Design/methodology/approach
The study was conducted in several service companies, and the study adopted the questionnaire as a basic tool for the data collection on the practical side, as 267 opinions were surveyed, in addition to conducting personal interviews, and the normal distribution of data was tested, analyzing, describing and diagnosing study variables, testing correlations and determining direct effects.
Findings
Findings show that there is no direct and significant statistical impact of information technology on organizational communications. Whereas there was a positive, direct and statistically significant impact of information technology on the organizational structure. There was also a positive, direct and statistically significant effect of the organizational structure on organizational communication.
Research limitations/implications
This paper is restricted to the role of the organizational structure as a mediating variable of the relationship between the influence of information technology on organizational communication.
Practical implications
As part of the practical implication, the paper suggests the need to increase support and attention to the importance of information technology in service organizations in order to increase coordination and organizational communication and achieve a high ability to explore and exploit ideas.
Originality/value
Apart from the fact that several companies were engaged, the organizational structures of these companies were engaged too to examine the impacts of Information technology (ICT) on organizational communication.
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Tian Zhang, Wendong Zhang, XingLing Shao and Yang Wu
Because of the small size and high integration of capacitive micromachined ultrasonic transducer (CMUT) component, it can be made into large-scale array, but this lead to high…
Abstract
Purpose
Because of the small size and high integration of capacitive micromachined ultrasonic transducer (CMUT) component, it can be made into large-scale array, but this lead to high hardware complexity, so the purpose of this paper is to use less elements to achieve better imaging results. In this research, an optimized sparse array is studied, which can suppress the side lobe and reduce the imaging artifacts compared with the equispaced sparse array with the same number of elements.
Design/methodology/approach
Genetic algorithm is used to sparse the CMUT linear array, and Kaiser window apodization is added to reduce imaging artifacts, the beam pattern and peak-to-side lobe ratio are calculated, point targets imaging comparisons are performed. Furthermore, a 256-elements CMUT linear array is used to carry out the imaging experiment of embedded mass and forearm blood vessel, and the imaging results are compared quantitatively.
Findings
Through the imaging comparison of embedded mass and forearm blood vessel, the feasibility of optimized sparse array of CMUT is verified, and the purpose of reducing the hardware complexity is achieved.
Originality/value
This research provides a basis for the large-scale CMUT array to reduce the hardware complexity and the amount of calculation. At present, the CMUT array has been used in medical ultrasound imaging and has huge market potential.
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Muhammad Faisal, Iftikhar Ahmad and Abdur Rashid
The present study aims to encompass the bidirectional magnetized flowing of a hybrid-nanofluid over an unsteady stretching device with the inclusion of thermal radiation and…
Abstract
Purpose
The present study aims to encompass the bidirectional magnetized flowing of a hybrid-nanofluid over an unsteady stretching device with the inclusion of thermal radiation and entropy generation. Brick-shaped nanoparticles (zinc-oxide and ceria) are suspended in water, serving as the base-fluid to observe the performance of the hybrid mixture. The Maxwell thermal conductivity relation is employed to link the thermophysical attributes of the hybrid mixture with the host liquid. Additionally, a heat source/sink term is incorporated in the energy balance to enhance the impact of the investigation. Both prescribed-surface-temperature (PST) and prescribed-heat-flux (PHF) conditions are applied to inspect the thermal performance of the hybrid nanofluid.
Design/methodology/approach
The transport equations in Cartesian configuration are transformed into ordinary differential equations (ODEs), and an efficient method, namely the Keller-Box method (KBM), is utilized to solve the transformed system. Postprocessing is conducted to visually represent the velocity profile, thermal distribution, skin-friction coefficients, Bejan number, Nusselt number and entropy generation function against the variations of the involved parameters.
Findings
It is observed that more entropy is generated due to the increases in temperature difference and radiation parameters. The Bejan number initially declines but then improves with higher estimations of unsteadiness and Hartmann number. Overall, the thermal performance of the system is developed for the PST scenario than the PHF scenario for different estimations of the involved constraints.
Originality/value
To the best of the authors' knowledge, no investigation has been reported yet that explains the bidirectional flow of a CeO2-ZnO/water hybrid nanofluid with the combined effects of prescribed thermal aspects (PST and PHF) and entropy generation.
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Mohammed T. Bani Salameh and Emad Shdouh
This study aims to identify the features and characteristics of feminist elites as well as their circulation rate in official political positions. The study questions include the…
Abstract
This study aims to identify the features and characteristics of feminist elites as well as their circulation rate in official political positions. The study questions include the role of a profession, educational level, and class of origin in the recruitment of feminist elites. It stems from the hypothesis that a direct correlation exists between the mechanism of recruiting feminist elites and their characteristics, according to the criterion of class differentiation based on social status and financial wealth. The study used a complex combination of scientific methodologies, including the elite approach, which is especially important as a result of its ability to convert arguments into measurable variables, and a comparative approach was used to compare the features and characteristics of feminist elites in two reigns. From the study, it was observed that feminist elites are characterized by caste and wealth, higher educational degree, and in addition obtaining degrees from Western universities, prevailed. This result demonstrates the higher value of Western universities. The study also found that the circulation rate of political feminist elites dramatically increased in the reign of King Abdullah compared with the appointed feminist elites in the reign of King Hussein.
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Isam Tareq Abdullah, Sabah Khammass Hussein and Abbas Khammas Hussein
The purpose of this paper is to join sheets of an aluminium alloy together with pre-holed carbon steel via friction spot technique.
Abstract
Purpose
The purpose of this paper is to join sheets of an aluminium alloy together with pre-holed carbon steel via friction spot technique.
Design/methodology/approach
An AISI 1006 steel sheet was a pre-holed with a 4.8 mm diameter and put under AA5052 sheet with a lap joint configuration. The joining process was carried out by extruding the aluminium through the steel hole using a rotating tool of 10 mm diameter. Furthermore, three process parameters (pre-heating time, rotating speed and plunging depth of the tool) with three values for each parameter were used to study their effects on the joints quality. In order to join samples, nine experiments were designed according to a Taguchi method. Shear strength, microstructure and X-ray diffraction tests of the joint were carried out.
Findings
The joining mechanism occurred by a mechanical interlock of the extruded aluminium with the inner surface of the steel hole. The tool plunging depth had a significant effect on the shear strength of the joint. The shear strength of two joints exceeded the shear strength of the wrought material (AA5052). All samples failed with two modes: pull-out and shearing of the extruded aluminium.
Originality/value
For the first time, the extrusion technique was used to join AA5052 sheet together with pre-holed carbon steel, with a perfect joint efficiency.
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Isam Tareq Abdullah, Sabah Khammass Hussein and Abbas Khammas Hussein
The purpose of this paper is to join aluminium alloy AA6061 with polyvinyl chloride (PVC) sheets using the friction spot technique.
Abstract
Purpose
The purpose of this paper is to join aluminium alloy AA6061 with polyvinyl chloride (PVC) sheets using the friction spot technique.
Design/methodology/approach
The AA6061 specimen was drilled with a semi-conical hole and put over the PVC specimen with a lap configuration. A friction spot technique was used to generate the required heat to melt and extrude the PVC through the aluminium hole. In this study, three process parameters were used: time, plunging depth and rotating speed of the tool. Thermal finite element model was built to analyse the process temperature. Effect of the process parameters on the joint shear strength and temperature was analysed using the design of experiments method. The microstructure investigation of the joint cross section was examined.
Findings
The input heat melted and extruded the polymer into the aluminium hole with the aid of tool pressure. A mechanical interlock was observed at the interface line between the polymer and aluminium. The scattered aluminium fragments into the molten polymer increased the shear strength of the joint. The hole diameter exhibited the highest effect on the joint strength compared with the other parameters. Specimen of minimum hole diameter recorded the maximum shear strength of 224 MPa. The proposed model gave a good agreement with the experimental data.
Originality/value
For the first time, the PVC was joined with AA6061 by the hot extrusion using the friction spot technique. The shear strength of joint reached 7.5 times of the base material (PVC).
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Asem Abdalrahim, Abdullah Alkhawaldeh, Mohammed ALBashtawy, Khitam Mohammad, Rasmieh Al-Amer, Omar Al Omari, Ahmad Ayed, Tariq Al-Dwaikat, Islam Oweidat, Haitham Khatatbeh, Mahmoud Alsaraireh, Sa'ad ALbashtawy and Khloud Al Dameery
This paper aims to explore the lived experience of people with a chronic non-healing wound and to explore what it means to live with a chronic wound.
Abstract
Purpose
This paper aims to explore the lived experience of people with a chronic non-healing wound and to explore what it means to live with a chronic wound.
Design/methodology/approach
A descriptive phenomenological study design was adopted to explore the living experience of person with chronic wound. A sample of 15 individuals of both genders was selected using a purposive sampling technique. To collect data, in-depth interviews were conducted, and all the interviews were audio-taped and transcribed verbatim. Data were analysed using the seven-step process described by Colaizzi (1978).
Findings
The findings were organized into 6 themes clusters and 12 themes. The six themes clusters were limiting mobility; receiving care; explaining causes of wounds; contending with chronic illnesses; adapting and mal-adapting; and economic burden of the wound.
Research limitations/implications
Chronic wound had a profound impact on participants’ lives by affecting their activities of daily living, their mobility, their income and their personal relationships.
Originality/value
Understanding the lived experiences of people with chronic wounds is crucial for health-care providers, including nurses. Investigating the chronic wound experience has become even more pressing given the projected increase in the number of elderly individuals and those with chronic illnesses such as diabetes mellitus. In Jordan, for example, the prevalence of diabetes mellitus is 17.1%, and it is projected to increase by 2050.
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Bee Choo Yee, Abdullah Mohd Nawi and Tina Abdullah
The sudden pandemic of COVID-19 has caused disruptive innovation in all areas of business including education. Despite the educators’ and students’ acceptance and readiness in the…
Abstract
Purpose
The sudden pandemic of COVID-19 has caused disruptive innovation in all areas of business including education. Despite the educators’ and students’ acceptance and readiness in the new normal, the traditional face-to-face (FTF) public speaking has been shifted to online courses to suit the current needs. This study aims to examine whether there were differences between online and FTF pubic speaking in the students’ anxiety level, speech performance, as well as their perceptions of the challenges in the implementation of online public speaking courses as a potential to disruptive innovation.
Design/methodology/approach
This pilot study was a mixed method research that involved a purposive sampling of two groups of 39 students in higher education. The instruments used were questionnaires of self-report anxiety, speech performance test and observation.
Findings
The findings show that the students preferred the traditional FTF rather than the online mode for public speaking courses. The challenges of internet connection and the lack of a live audience were their main concerns in online public speaking. It also provides a potential for disruptive innovation that could take into consideration of a live audience in university online courses.
Originality/value
This study provides the potential of public speaking course as a disruptive innovation. This brings implications for the innovators, marketers and educators to think of the online courses/programmes that can be best implemented while embracing the changes and the new normal of COVID-19 brings for student learning.