Lotfi Hidri

Dr. Lotfi Hidri


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2020 in Advances in Materials Science and Engineering
Verified
Journal Article
Open access
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AGAtef Ghaleb
Atef Ghaleb
Husam KaidHusam Kaid
Husam Kaid
AAAli Alsamhan
Ali Alsamhan
SMSyed Hammad Mian
Syed Hammad Mian
LHLotfi Hidri
Lotfi Hidri
The selection of manufacturing processes for a given application is a complex problem of multicriteria decision‐making although there have been several different approaches that can be utilized to select a suitable alternative. However, identifying appropriate multicriteria decision‐making approach from the list of available methods for a given application is a difficult task. This work suggests a methodology to assess different selection approaches, which are the technique for order of preference by similarity to ideal solution (TOPSIS), analytic hierarchy process (AHP), and VIKOR: stepwise procedure. This valuation was done depending on the following factors: number of alternative processes and criteria, agility through the process of decision‐making, computational complexity, adequacy in supporting a group decision, and addition or removal of a criterion. A case study in this study was presented to analyse the evaluation methodology. The criteria used to evaluate and identify the best manufacturing process were categorized into productivity, accuracy, complexity, flexibility, material utilization, quality, and operation cost. Five manufacturing processes were considered, including gravity die casting, investment casting, pressure die casting, sand casting, and additive manufacturing. The results showed that each approach was suitable for the problems of manufacturing process selection, in particular toward the support of group decision‐making and uncertainty modelling. Manufacturing processes were ranked based on their respective weights for AHP, TOPSIS, and VIKOR, and sand casting is the best. In terms of computational complexity, the VIKOR method performed better than TOPSIS and AHP. Moreover, the VIKOR and TOPSIS methods were better convenient to the selection of manufacturing processes for agility during the process of decision‐making, the number of alternative processes and criteria, adequacy in supporting a group decision, and addition or removal of a criterion.

21 August 2019 in Advances in Materials Science and Engineering
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Journal Article
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Mohammed M. MabkhotMohammed M. Mabkhot
Mohammed M. Mabkhot
AAAli M Alsamhan
Ali M Alsamhan
LHLotfi Hidri
Lotfi Hidri
In nowadays industry 4.0 and changeable manufacturing context, designers and manufacturing engineers struggle to determine appropriate quick, accurate (with flawless quality), and cost-effective processes to design highly customized products to meet customer requirements. To determine manufacturing processes, the matching between product features, material characteristics, and process capabilities needs to be optimized. Finding such an optimized matching is usually referred to as manufacturing process selection (MPS), which is not an easy task because of the infinite combinations of product features, numerous material characteristics, and various manufacturing processes. Although problems associated with MPS have received considerable attention, semantic web technologies are still underexplored and their potential is still uncovered. Almost no previous study has considered combining case-based reasoning (CBR) with ontologies, a famous and powerful semantic web enabler, to achieve MPS. In this study, we developed a decision support system (DSS) for MPS based on ontology-enabled CBR. By applying automatic reasoning and similarity retrieving on an industrial case study, we show that ontologies enable process selection by determining competitive matching between product features, material characteristics, and process capabilities and by endorsing effective case retrieval.

12 April 2018 in IEEE Access
Verified
Journal Article
Open access
LHLotfi Hidri
Lotfi Hidri
SESabeur Elkosantini
Sabeur Elkosantini
Mohammed M. MabkhotMohammed M. Mabkhot
Mohammed M. Mabkhot
This paper addresses the two centers hybrid flow shop scheduling problem with transportation times. This problem is faced in several real-world applications. The considered objective function to be minimized in this problem is the maximum completion time. This scheduling problem is NP-hard, and most presented research in this scheduling area ignore the transportation times. In order to solve the considered scheduling problem, several lower bounds are developed. In addition, a two phase's heuristic is presented. This heuristic is based on the optimal solution of the parallel machine scheduling problem with release date and delivery time. Furthermore, a branch and bound exact procedure is developed. Finally, extensive numerical experiments are presented in order to asses the performance and the effectiveness of the proposed procedures. Computational results provide evidence that the proposed procedures are very effective in term of producing optimal solutions in a short computational time for large size problems.

28 February 2020 in IEEE Access
Verified
Journal Article
Open access
AQAmmar Qamhan
Ammar Qamhan
AAAref Ahmed
Aref Ahmed
IAIbarhim Alharkan
Ibarhim Alharkan
Ahmed BadwelanAhmed Badwelan
Ahmed Badwelan
AAAli M Alsamhan
Ali M Alsamhan
LHLotfi Hidri
Lotfi Hidri
This paper considers a time window periodic maintenance strategy with different duration windows and job scheduling activities in a single machine environment. The aim is to minimize the number of tardy jobs through the integration of production scheduling and periodic maintenance intervals. A mixed-integer linear programming model (MILP) is proposed to optimize small-sized test instances. Furthermore, an ant colony optimization (ACO) algorithm is developed to solve larger sized test instances. Subsequently, to measure the efficiency of the solutions obtained by ACO, Moore’s algorithm is also developed to benchmark with ACO. To test the efficiency and the effectiveness of the ACO algorithm, a set of data for small and large sized problems was generated in which several parameters were adopted and then ten replicates were solved for each combination. The small sized instances were solved by the MILP. Then, the results obtained showed that the proposed ACO was able to obtain the exact solutions within reasonable CPU times, thus, it outperformed the CPLEX solver with respect to CPU. The large sized instances were solved by the Moore’s algorithm and compared to ACO. Then, the results obtained showed that the ACO outperforms Moore’s algorithm for all the instances tested. It can be concluded that the developed ACO is very efficient and effective in solving the problem considered in this paper.

2 March 2020 in RAIRO - Operations Research
Verified
Journal Article
Closed access
LHLotfi Hidri
Lotfi Hidri
MJMahdi Jemmali
Mahdi Jemmali
In this paper, the parallel machines scheduling problem with Dejong’s learning effect is addressed. The considered problem has a practical interest since it models real-world situations. In addition, this problem is a challenging one because of its NP-Hardness. In this work, a set of heuristics are proposed. The developed heuristics are categorized into two types. The first category is based on the dispatching methods, with new enhancement variants. The second type is more sophisticated and requires solving NP-Hard problems. Furthermore, several lower bounds are developed in order to assess the performance of the proposed heuristics. These lower bounds are based on solving the problem of the determination of the minimum average load under taking into account some observations. Among these observations, the existence of a limit position that the jobs are not allowed to exceed in any optimal schedule. Finally, an extensive experimental study is conducted over benchmark test problems, with up to 1500 jobs and 5280 instances. The obtained results are outperforming those proposed in the literature.

18 August 2021 in Sustainability
Verified
Journal Article
Open access
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LHLotfi Hidri
Lotfi Hidri
AAAli Alqahtani
Ali Alqahtani
AGAchraf Gazdar
Achraf Gazdar
BYBelgacem Ben Youssef
Belgacem Ben Youssef
Global warming and climate change are threatening life on earth. These changes are due to human activities resulting in the emission of greenhouse gases. This is caused by intensive industrial activities and excessive fuel energy consumption. Recently, the scheduling of production systems has been judged to be an effective way to reduce energy consumption. This is the field of green scheduling, which aims to allocate jobs to machines in order to minimize total costs, with a focus on the sustainable use of energy. Several studies have investigated parallel-machine shops, with a special focus on reducing and minimizing the total consumed energy. Few studies explicitly include the idle energy of parallel machines, which is the energy consumed when the machines are idle. In addition, very few studies have considered the elimination of idle machine times as an efficient way to reduce the total consumed energy. This is the no-idle machine constraint, which is the green aspect of the research. In this context, this paper addresses the green parallel-machine scheduling problem, including release dates, delivery times, and no-idle machines, with the objective of minimizing the maximum completion time. This problem is of practical interest since it is encountered in several industry processes, such as the steel and automobile industries. A mixed-integer linear programming (MILP) model is proposed for use in obtaining exact solutions for small-sized instances. Due to the NP-hardness of the studied problem, and encouraged by the successful adaptation of metaheuristics for green scheduling problems, three genetic algorithms (GAs) using three different crossover operators and a simulated annealing algorithm (SA) were developed for large-sized problems. A new family of lower bounds is proposed. This was intended for the evaluation of the performance of the proposed algorithms over the average percent of relative deviation (ARPD). In addition, the green aspect was evaluated over the percentage of saved energy, while eliminating the idle-machine times. An extensive experimental study was carried out on a benchmark of test problems with up to 200 jobs and eight machines. This experimental study showed that one GA variant dominated the other proposed procedures. Furthermore, the obtained numerical results provide strong evidence that the proposed GA variant outperformed the existing procedures from the literature. The experimental study also showed that the adoption of the no-idle machine time constraints made it possible to reduce the total consumed energy by 29.57%, while the makespan (cost) increased by only 0.12%.