Ebrahim Yousefi, Morteza Adineh and Mohammad Bagher Askari
The purpose of this paper is to fabricate zirconia-nano alumina porous nanocomposites with different amount of alumina (0-30 Wt.%). Specimens were prepared by solid state…
Abstract
Purpose
The purpose of this paper is to fabricate zirconia-nano alumina porous nanocomposites with different amount of alumina (0-30 Wt.%). Specimens were prepared by solid state sintering method at different temperature (1,400-1,700°C).
Design/methodology/approach
Effects of processing temperature and amount of alumina on microstructure, distribution of nanoparticles, flexural and compressive strengths, micro-hardness and densification were investigated.
Findings
Results indicated that interpenetration of particles and their contacts increased by increasing sintering temperature. As a consequence of better particles contacts and microstructure coarsening, the porosity decreased. As alumina nanoparticles content increased, the amount of porosity decreased conversely and distribution of pores become more uniform. Simultaneous enhancement of temperature and alumina nanoparticles content caused an improvement of flexural and compressive strengths because of an improvement of sintering process resulted from porosity reduction. Increase in hardness and density were observed as porosity values diminished and alumina nanoparticles were distributed well at micro zirconia grain boundaries as a result of increasing the process temperature.
Originality/value
This article contains original research.
Details
Keywords
Leila Hashemi, Armin Mahmoodi, Milad Jasemi, Richard C. Millar and Jeremy Laliberté
This study aims to investigate a locating-routing-allocating problems and the supply chain, including factories distributor candidate locations and retailers. The purpose of this…
Abstract
Purpose
This study aims to investigate a locating-routing-allocating problems and the supply chain, including factories distributor candidate locations and retailers. The purpose of this paper is to minimize system costs and delivery time to retailers so that routing is done and the location of the distributors is located.
Design/methodology/approach
The problem gets closer to reality by adding some special conditions and constraints. Retail service start times have hard and soft time windows, and each customer has a demand for simultaneous delivery and pickups. System costs include the cost of transportation, non-compliance with the soft time window, construction of a distributor, purchase or rental of a vehicle and production costs. The conceptual model of the problem is first defined and modeled and then solved in small dimensions by general algebraic modeling system (GAMS) software and non-dominated sorting genetic algorithm II (NSGAII) and multiple objective particle swarm optimization (MOPSO) algorithms.
Findings
According to the solution of the mathematical model, the average error of the two proposed algorithms in comparison with the exact solution is less than 0.7%. Also, the algorithms’ performance in terms of deviation from the GAMS exact solution, is quite acceptable and for the largest problem (N = 100) is 0.4%. Accordingly, it is concluded that NSGAII is superior to MOSPSO.
Research limitations/implications
In this study, since the model is bi-objective, the priorities of decision makers in choosing the optimal solution have not been considered and each of the objective functions has been given equal importance according to the weighting methods. Also, the model has not been compared and analyzed in deterministic and robust modes. This is because all variables, except the one that represents the uncertainty of traffic modes, are deterministic and the random nature of the demand in each graph is not considered.
Practical implications
The results of the proposed model are valuable for any group of decision makers who care optimizing the production pattern at any level. The use of a heterogeneous fleet of delivery vehicles and application of stochastic optimization methods in defining the time windows, show how effective the distribution networks are in reducing operating costs.
Originality/value
This study fills the gaps in the relationship between location and routing decisions in a practical way, considering the real constraints of a distribution network, based on a multi-objective model in a three-echelon supply chain. The model is able to optimize the uncertainty in the performance of vehicles to select the refueling strategy or different traffic situations and bring it closer to the state of certainty. Moreover, two modified algorithms of NSGA-II and multiple objective particle swarm optimization (MOPSO) are provided to solve the model while the results are compared with the exact general algebraic modeling system (GAMS) method for the small- and medium-sized problems.
Details
Keywords
Bianca Arcifa de Resende, Franco Giuseppe Dedini, Jony Javorsky Eckert, Tiago F.A.C. Sigahi, Jefferson de Souza Pinto and Rosley Anholon
This study aims to propose a facilitating methodology for the application of Fuzzy FMEA (Failure Mode and Effect Analysis), comparing the traditional approach with fuzzy…
Abstract
Purpose
This study aims to propose a facilitating methodology for the application of Fuzzy FMEA (Failure Mode and Effect Analysis), comparing the traditional approach with fuzzy variations, supported by a case application in the aeronautical sector.
Design/methodology/approach
Based on experts' opinions in risk analysis within the aeronautical sector, rules governing the relationship between severity, occurrence, detection and risk factor were defined. This served as input for developing a fuzzyfied FMEA tool using the Matlab Fuzzy Logic Toolbox. The tool was applied to the sealing process in a company within the aeronautical sector, using triangular and trapezoidal membership functions, and the results were compared with the traditional FMEA approach.
Findings
The results of the comparative application of traditional FMEA and fuzzyfied FMEA using triangular and trapezoidal functions have yielded valuable insights into risk analysis. The findings indicated that fuzzyfied FMEA maintained coherence with the traditional analysis in identifying higher-risk effects, aligning with the prioritization of critical failure modes. Additionally, fuzzyfied FMEA allowed for a more refined prioritization by accounting for variations in each variable through fuzzy rules, thereby improving the accuracy of risk analysis and providing a more realistic representation of potential hazards. The application of the developed fuzzyfied FMEA approach showed promise in enhancing risk assessment in the aeronautical sector by considering uncertainties and offering a more detailed and context-specific analysis compared to conventional FMEA.
Practical implications
This study emphasizes the potential of fuzzyfied FMEA in enhancing risk assessment by accurately identifying critical failure modes and providing a more realistic representation of potential hazards. The application case reveals that the proposed tool can be integrated with expert knowledge to improve decision-making processes and risk mitigation strategies within the aeronautical industry. Due to its straightforward approach, this facilitating methodology could also prove beneficial in other industrial sectors.
Originality/value
This paper presents the development and application of a facilitating methodology for implementing Fuzzy FMEA, comparing it with the traditional approach and incorporating variations using triangular and trapezoidal functions. This proposed methodology uses the Toolbox Fuzzy Logic of Matlab to create a fuzzyfied FMEA tool, enabling a more nuanced and context-specific risk analysis by considering uncertainties.
Details
Keywords
Nur Syazwani Ahmad, Shamshul Bahri and Ali Fauzi
This study aims to explore how the use of mobile instant messaging (MIM) in an organization has led to the decentralization of authority.
Abstract
Purpose
This study aims to explore how the use of mobile instant messaging (MIM) in an organization has led to the decentralization of authority.
Design/methodology/approach
To achieve this aim, a study was conducted on a case site that had used MIM extensively to manage an event.
Findings
This study found that communication technology such as MIM can shift more authority to the lower-level committees through the processes of formation, delegation, control and dissolution.
Originality/value
The role of information systems and technology in affecting a decentralization process has been largely understudied. Additionally, the effect of communication technologies such as MIM on a decentralization process has been largely ignored. Therefore, this study theorizes the role of MIM in managing an event and how the technology has decentralized more authority from the top management to the lower-level committees.
Details
Keywords
Due to environmental and health awareness, there are a number of green startups increasing day by day and consumers want to use organic products over conventional products. The…
Abstract
Purpose
Due to environmental and health awareness, there are a number of green startups increasing day by day and consumers want to use organic products over conventional products. The green enterprise faces unique challenges and opportunities in attracting the right investors, organization growth and their performance. The purpose of this study is to better understand the relationship between green entrepreneurship (GE) and different leadership styles (LS) and their association with organizational growth (OG).
Design/methodology/approach
This paper proposes a methodology based on multiple independent variables and one dependent variable i.e. multiple regression analysis. A numerical analysis of the Indian organization is presented to demonstrate the use of the proposed method.
Findings
The findings indicate that different LSs (charismatic, transformational, visionary and servant leadership) feature an influence on entrepreneurial activity. The result of the study also found that GE and LS have a positive effect on OG.
Research limitations/implications
This research will help the industry reflect on the style of leadership and attempt to introduce a new style of leadership that supports and is suitable for the green organization’s growth.
Originality/value
The study identified diverse LSs that specifically plays an important role in green entrepreneurship organizations. Additionally, investigate the relationship between OG and GE.
Details
Keywords
Khaled Elmawazini, Khiyar Abdullah Khiyar and Asiye Aydilek
This paper aims to compare the effects of Islamic and commercial banks on economic growth among the Gulf Cooperation Council (GCC) countries during 2001–2009 (before and during…
Abstract
Purpose
This paper aims to compare the effects of Islamic and commercial banks on economic growth among the Gulf Cooperation Council (GCC) countries during 2001–2009 (before and during the financial crisis) and 2010–2017 (after the financial crisis).
Design/methodology/approach
The authors use a cross-sectionally correlated and timewise autoregressive (CCTA) model. The authors also extend the theoretical endogenous growth model developed by Pagano (1993) by introducing the developments in Islamic and commercial financial markets.
Findings
The authors find that Islamic banks fueled economic growth more than conventional banks before and after the financial crisis. The authors conclude that finance is a major determinant of economic growth, but finance does not follow economic growth. The results show that the ethical principles of Islamic finance can positively affect economic growth.
Originality/value
The authors contribute to the empirical literature first by examining feedback causality and cointegration between the banking sector and economic growth by examining the impact of the interaction between the banking sector and rule of law on economic growth in the GCC countries instead of a single country, second by providing both of the theoretical and empirical analysis and third by distinguishing between Islamic and conventional banks.