Mauricio E. Pilleux, Ahmad Safari, Mehdi Allahverdi, Youren Chen, Yicheng Lu and Mohsen A. Jafari
Three‐dimensional photonic bandgap (PBG) structures using alumina (Al2O3) as the high permittivity material were modeled and then the structures were fabricated by Fused…
Abstract
Three‐dimensional photonic bandgap (PBG) structures using alumina (Al2O3) as the high permittivity material were modeled and then the structures were fabricated by Fused Deposition of Multi‐materials (FDMM) technology. A finite element method and a real‐time electromagnetic wave propagation software were used to simulate and design the layered PBG structures for applications in the microwave frequency range. The modeling predicted a 3‐D photonic bandgap in the 16.5–23.5 GHz range. FDMM provides a computer‐controlled process to generate 3‐D structures, allowing high fabrication flexibility and efficiency. Electromagnetic measurements displayed the presence of a bandgap between 17.1–23.3 GHz, showing a good agreement with the predicted values. These PBG structures are potential candidates for applications in advanced communication systems.
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Wenbiao Han, Mohsen A. Jafari and Kian Seyed
Compared to conventional manufacturing processes, fused deposition (FD)‐based layered manufacturing processes have dramatically reduced the part design and manufacturing time…
Abstract
Compared to conventional manufacturing processes, fused deposition (FD)‐based layered manufacturing processes have dramatically reduced the part design and manufacturing time. However, it is necessary to further enhance their process productivity. To this end, improvement of FD process efficiency is studied in this paper. A build time analysis is conducted and the deposition parameters that can be used to speed up fabrication processes are identified. The tool path‐based deposition planning approach is extended for ensuring layer quality when the build process is expedited under adjusted deposition parameters. A test part was built to demonstrate the proposed approach.
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Dan Qiu, Noshir A. Langrana, Stephen C. Danforth, Ahmad Safari and Mohsen Jafari
To fabricate high quality parts, and to make the development generic yet compatible with the in‐house hardware, a virtual simulation system has been developed, and an in‐house…
Abstract
To fabricate high quality parts, and to make the development generic yet compatible with the in‐house hardware, a virtual simulation system has been developed, and an in‐house intelligent multi‐material toolpath generation system has been under development. This new development includes the issues such as multiple fill‐toolpaths for the same material, interface mismatch between adjacent materials and the intelligent toolpath features for machine control. After the multi‐material toolpath file generated by the in‐house software, the existing virtual graphical simulation as well as well selected part fabrication experiments were used to validate it. Based on the authors’ ongoing research about multi‐material layered manufacturing, it was determined that the build characteristic was heavily dependent on the material being used. Therefore, it was important to develop the hardware/software that will accommodate this requirement.
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Mohsen Sadeghi-Dastaki and Abbas Afrazeh
Human resources are one of the most important and effective elements for companies. In other words, employees are a competitive advantage. This issue is more vital in the supply…
Abstract
Purpose
Human resources are one of the most important and effective elements for companies. In other words, employees are a competitive advantage. This issue is more vital in the supply chains and production systems, because of high need for manpower in the different specification. Therefore, manpower planning is an important, essential and complex task. The purpose of this paper is to present a manpower planning model for production departments. The authors consider workforce with individual and hierarchical skills with skill substitution in the planning. Assuming workforce demand as a factor of uncertainty, a two-stage stochastic model is proposed.
Design/methodology/approach
To solve the proposed mixed-integer model in the real-world cases and large-scale problems, a Benders’ decomposition algorithm is introduced. Some test instances are solved, with scenarios generated by Monte Carlo method. For some test instances, to find the number of suitable scenarios, the authors use the sample average approximation method and to generate scenarios, the authors use Latin hypercube sampling method.
Findings
The results show a reasonable performance in terms of both quality and solution time. Finally, the paper concludes with some analysis of the results and suggestions for further research.
Originality/value
Researchers have attracted to other uncertainty factors such as costs and products demand in the literature, and have little attention to workforce demand as an uncertainty factor. Furthermore, most of the time, researchers assume that there is no difference between the education level and skill, while they are not necessarily equivalent. Hence, this paper enters these elements into decision making.
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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.
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Mohsen Babaei, Afshin Shariat-Mohaymany, Nariman Nikoo and Ahmad-Reza Ghaffari
One of the problems in post-earthquake disaster management in developing countries, such as Iran, is the prediction of the residual network available for disaster relief…
Abstract
Purpose
One of the problems in post-earthquake disaster management in developing countries, such as Iran, is the prediction of the residual network available for disaster relief operations. Therefore, it is important to use methods that are executable in such countries given the limited amount of accurate data. The purpose of this paper is to present a multi-objective model that seeks to determine the set of roads of a transportation network that should preserve its role in carrying out disaster relief operations (i.e. known as “emergency road network” (ERN)) in the aftermath of earthquakes.
Design/methodology/approach
In this paper, the total travel time of emergency trips, the total length of network and the provision of coverage to the emergency demand/supply points have been incorporated as three important metrics of ERN into a multi-objective mixed integer linear programming model. The proposed model has been solved by adopting the e-constraint method.
Findings
The results of applying the model to Tehran’s highway network indicated that the least possible length for the emergency transportation network is about half the total length of its major roads (freeways and major arterials).
Practical implications
Gathering detailed data about origin-destination pair of emergency trips and network characteristics have a direct effect on designing a suitable emergency network in pre-disaster phase.
Originality/value
To become solvable in a reasonable time, especially in large-scale cases, the problem has been modeled based on a decomposing technique. The model has been solved successfully for the emergency roads of Tehran within about 10 min of CPU time.
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Abdoulaye Kaba and Chennupati K. Ramaiah
The purpose of this research paper is to report about an investigation on the relationship between knowledge acquisition and knowledge creation to find out whether knowledge…
Abstract
Purpose
The purpose of this research paper is to report about an investigation on the relationship between knowledge acquisition and knowledge creation to find out whether knowledge acquisition can predict knowledge creation. The study measures the concept of knowledge acquisition through the faculty use of knowledge acquisition tools and reading knowledge sources while measuring the concept of knowledge creation through the faculty use of knowledge creation tools and publishing knowledge sources.
Design/methodology/approach
The population of the study is faculty members in the United Arab Emirates (UAE). The sample of the population consisted of 300 faculty members affiliated with 26 universities and colleges. Data was collected from the sample through questionnaire instrument. Stated hypotheses and Mathew’s theory of knowledge consumption–production correlation are tested and verified through correlation matrix and regression analysis.
Findings
Findings of the study revealed that the use of knowledge acquisition tools by faculty members has a positive effect on the use of knowledge creation tools and on publishing knowledge sources. Likewise, reading knowledge sources appeared to have a positive impact on the use of knowledge creation tools and publishing knowledge sources. Accordingly, the study confirmed the stated four hypotheses. Moreover, the results of the study supported the theory of knowledge consumption–production correlation and strongly confirmed the prediction of knowledge creation through the use of information and communication technology (ICT) tools for knowledge acquisition and reading knowledge sources.
Practical implications
Findings of the study appeal to the decision-makers and stakeholders of academic institutions to make effective investment in ICT facilities and knowledge sources to improve knowledge creation among faculty members.
Originality/value
Not many studies have investigated how knowledge acquisition can predict knowledge creation in the academic environment. This paper contributes to the understanding of the relationship between knowledge acquisition and knowledge creation in academic settings. Findings of the study can be an important reference for providing and improving knowledge sources, knowledge acquisition tools and knowledge creation tools in the academic environment.
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Zaid Jaradat, Ahmad Mtair AL-Hawamleh and Marwan Altarawneh
The aim of this study is to investigate technological and innovation orientation contribution to the development and sustainability of the industrial sector.
Abstract
Purpose
The aim of this study is to investigate technological and innovation orientation contribution to the development and sustainability of the industrial sector.
Design/methodology/approach
The authors gathered the perspectives of many experts who were aware enough of their company’s technical and innovation orientations to participate in this study to understand how technology and innovation orientations may affect sustainability and development. These people included the company managers, accounting department heads, IT department workers and employees in the innovation department. This was accomplished by distributing a thorough questionnaire intended to gather their perspectives.
Findings
The study’s results highlight the significant positive relationship between technological and innovation orientation. Moreover, the study demonstrates that both technological and innovation orientation were found to positively impact the sustainability and development of the industrial sector.
Practical implications
This study provides practical insights for policymakers, industrial managers and innovation supporters in Jordan. Managers can use these insights to reassess technology adoption and innovation strategies. Additionally, investing in staff skills and technology readiness can boost efficiency, competitiveness and long-term growth.
Originality/value
To the best of the authors’ knowledge, this study is pioneering research to shed light on the connection between technological orientation, innovation orientation and sustainability and development in the industrial sector, providing valuable insights for policymakers and practitioners alike.
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Zahy Ramadan and Nour Zakaria Nsouli
With US$ 320 bn spent on luxury fashion in the Middle East and a growing digital consumer presence, local start-ups must form an integrated online relationship with millennials in…
Abstract
Purpose
With US$ 320 bn spent on luxury fashion in the Middle East and a growing digital consumer presence, local start-ups must form an integrated online relationship with millennials in order to recruit and retain a viable customer base. Nonetheless, these elements are yet to be extensively and properly researched as the literature is still scarce vis-à-vis this area.
Design/methodology/approach
A mixed qualitative approach was adopted using both in-depth interviews and focus groups. Two qualitative studies were conducted, with a total of 13 elite respondents and 28 consumer respondents from Saudi Arabia and the United Arab Emirates (UAE) using semi-structured interviews. Four focus groups were also conducted in both countries with six participants each group for triangulation of the findings.
Findings
The findings enhance current understanding pertaining to Gen Ys' motivations when selecting and engaging online with a luxury fashion start-up brand. The study suggests a detailed strategic framework that can be used in an integrated omni-channel approach. It also discusses the different touchpoints that play a role in influencing luxury consumption across different motivation stages.
Originality/value
The literature relating to digital strategies for luxury fashion start-up brands in the Middle East is still nascent. This study fills a considerable gap in the literature related to such brands that are aiming to stay relevant amidst the growing impact of the digital landscape on luxury fashion brand shoppers in the Middle East.