Publications

2022
Moumen L, Rebiai S-E. Exponential stability of the transmission wave equation with a distributed delay term in the boundary damping. Rendiconti del circolo matematico di palermo series 2 [Internet]. 2022;72 :3459–3486. Publisher's VersionAbstract

We consider a system of transmission of the wave equation with Neumann feedback control that contains a distributed delay term and that acts on the exterior boundary. We prove under some assumptions that the solutions decay exponentially in an appropriate energy space. To establish this result, we introduce a suitable energy function and use multipliers technique method and compactness-uniqueness argument.

Bensalem I, Benhizia A. Novel design of irregular closed-cell foams structures based on spherical particle inflation and evaluation of its compressive performance. Thin-Walled Structures [Internet]. 2022;181. Publisher's VersionAbstract

Due to the high degree of randomness in the microstructure of real closed-cell foams, many reported numerical models in the literature are not able to capture precisely the local morphological features found in solid foams geometry. This is still the main impediment that restricts the investigation of this novel material and motivates the development of a sophisticated 3D solid model, which describes properly the complex geometry of real closed-cell foams. In this regard, this paper presents an original approach to generate a realistic and accurate 3D computational model of irregular closed-cell foams with relative density control and detailed finite element analysis of their mechanical performance under quasi-static loading up to densification. The solid model is constructed based on spherical particles inflation simulation. It resembles the real foams in terms of local features such as cell walls irregularities and thickness variation. The modeling approach was successfully verified by comparing cell-morphological details of the generated models with those produced experimentally available in the literature and by the high-quality of obtained 3D printed models containing complex shapes and irregular cell wall thickness distribution. The evolution of spherical particles during the inflation process is analyzed based on finite element (FE) simulations. It was found that it can produce varying relative densities of foam due to the gradual decrease in the gap between the inflated particles, this makes the geometrical model of the foam suitable for studying the effect of local morphological characteristics on the mechanical performance of closed-cell foam material. To demonstrate that the compressive performance of the proposed closed-cell foam models can be controlled by relative density, 3D foam models were extracted from different inflation times and then subjected to quasi-static compression tests up to densification using the Abaqus software. The results confirm that the plateau stress can be expressed as a function of foam relative density, its accuracy is validated by comparing it to the closed-cell aluminum foam power law equation existing in the literature. The new design method offers suitable numerical models for AM technology, plenty of experimental works on closed-cell foam can be reduced for engineering applications.

Bensalem I, Benhizia A. Novel design of irregular closed-cell foams structures based on spherical particle inflation and evaluation of its compressive performance. Thin-Walled Structures [Internet]. 2022;181. Publisher's VersionAbstract

Due to the high degree of randomness in the microstructure of real closed-cell foams, many reported numerical models in the literature are not able to capture precisely the local morphological features found in solid foams geometry. This is still the main impediment that restricts the investigation of this novel material and motivates the development of a sophisticated 3D solid model, which describes properly the complex geometry of real closed-cell foams. In this regard, this paper presents an original approach to generate a realistic and accurate 3D computational model of irregular closed-cell foams with relative density control and detailed finite element analysis of their mechanical performance under quasi-static loading up to densification. The solid model is constructed based on spherical particles inflation simulation. It resembles the real foams in terms of local features such as cell walls irregularities and thickness variation. The modeling approach was successfully verified by comparing cell-morphological details of the generated models with those produced experimentally available in the literature and by the high-quality of obtained 3D printed models containing complex shapes and irregular cell wall thickness distribution. The evolution of spherical particles during the inflation process is analyzed based on finite element (FE) simulations. It was found that it can produce varying relative densities of foam due to the gradual decrease in the gap between the inflated particles, this makes the geometrical model of the foam suitable for studying the effect of local morphological characteristics on the mechanical performance of closed-cell foam material. To demonstrate that the compressive performance of the proposed closed-cell foam models can be controlled by relative density, 3D foam models were extracted from different inflation times and then subjected to quasi-static compression tests up to densification using the Abaqus software. The results confirm that the plateau stress can be expressed as a function of foam relative density, its accuracy is validated by comparing it to the closed-cell aluminum foam power law equation existing in the literature. The new design method offers suitable numerical models for AM technology, plenty of experimental works on closed-cell foam can be reduced for engineering applications.

YOUSFI H, Brioua M, Benbouta R. STUDY AND PREDICTION OF THE FATIGUE LIFE OF AISI 1045 STEEL STRUCTURES UNDER ROTATIONAL BENDING STRESSES. UPB scientific bulletin series d mechanical engineering [Internet]. 2022;84 (2). Publisher's VersionAbstract

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

YOUSFI H, Brioua M, Benbouta R. STUDY AND PREDICTION OF THE FATIGUE LIFE OF AISI 1045 STEEL STRUCTURES UNDER ROTATIONAL BENDING STRESSES. UPB scientific bulletin series d mechanical engineering [Internet]. 2022;84 (2). Publisher's VersionAbstract

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

YOUSFI H, Brioua M, Benbouta R. STUDY AND PREDICTION OF THE FATIGUE LIFE OF AISI 1045 STEEL STRUCTURES UNDER ROTATIONAL BENDING STRESSES. UPB scientific bulletin series d mechanical engineering [Internet]. 2022;84 (2). Publisher's VersionAbstract

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

YAHIA-CHERIF SALAH, BENOUDJIT D, NAIT-SAID MS, NAIT-SAID N. INCIPIENT SHORTCIRCUIT FAULT IMPACT ON SERVICE CONTINUITY OF AN ELECTRIC VEHICLE PROPELLED BY DUAL INDUCTION MOTORS STRUCTURE. Revue Roumaine des Sciences Techniques, Série Électrotechnique et Énergétique [Internet]. 2022;67 (3) :265–270. Publisher's VersionAbstract
The short circuit is among one of the most dangerous electrical faults in induction motors, which leads to serious implications on the motor operation and its performance. The present paper deals with the influence of the stator short circuit fault in its early stage in terms of performanceand service continuity of an electric vehicle (EV) using a dual induction motor’s structure piloted by Backstepping control. An equivalent induction motor model with turn-to-turn fault on one stator phase, without already assuming the temperature effect through an intrinsic model, is investigated. Afterward,its impacts on electric vehicle performance using simulation tests are presented anddiscussed.
YAHIA-CHERIF SALAH, BENOUDJIT D, NAIT-SAID MS, NAIT-SAID N. INCIPIENT SHORTCIRCUIT FAULT IMPACT ON SERVICE CONTINUITY OF AN ELECTRIC VEHICLE PROPELLED BY DUAL INDUCTION MOTORS STRUCTURE. Revue Roumaine des Sciences Techniques, Série Électrotechnique et Énergétique [Internet]. 2022;67 (3) :265–270. Publisher's VersionAbstract
The short circuit is among one of the most dangerous electrical faults in induction motors, which leads to serious implications on the motor operation and its performance. The present paper deals with the influence of the stator short circuit fault in its early stage in terms of performanceand service continuity of an electric vehicle (EV) using a dual induction motor’s structure piloted by Backstepping control. An equivalent induction motor model with turn-to-turn fault on one stator phase, without already assuming the temperature effect through an intrinsic model, is investigated. Afterward,its impacts on electric vehicle performance using simulation tests are presented anddiscussed.
YAHIA-CHERIF SALAH, BENOUDJIT D, NAIT-SAID MS, NAIT-SAID N. INCIPIENT SHORTCIRCUIT FAULT IMPACT ON SERVICE CONTINUITY OF AN ELECTRIC VEHICLE PROPELLED BY DUAL INDUCTION MOTORS STRUCTURE. Revue Roumaine des Sciences Techniques, Série Électrotechnique et Énergétique [Internet]. 2022;67 (3) :265–270. Publisher's VersionAbstract
The short circuit is among one of the most dangerous electrical faults in induction motors, which leads to serious implications on the motor operation and its performance. The present paper deals with the influence of the stator short circuit fault in its early stage in terms of performanceand service continuity of an electric vehicle (EV) using a dual induction motor’s structure piloted by Backstepping control. An equivalent induction motor model with turn-to-turn fault on one stator phase, without already assuming the temperature effect through an intrinsic model, is investigated. Afterward,its impacts on electric vehicle performance using simulation tests are presented anddiscussed.
YAHIA-CHERIF SALAH, BENOUDJIT D, NAIT-SAID MS, NAIT-SAID N. INCIPIENT SHORTCIRCUIT FAULT IMPACT ON SERVICE CONTINUITY OF AN ELECTRIC VEHICLE PROPELLED BY DUAL INDUCTION MOTORS STRUCTURE. Revue Roumaine des Sciences Techniques, Série Électrotechnique et Énergétique [Internet]. 2022;67 (3) :265–270. Publisher's VersionAbstract
The short circuit is among one of the most dangerous electrical faults in induction motors, which leads to serious implications on the motor operation and its performance. The present paper deals with the influence of the stator short circuit fault in its early stage in terms of performanceand service continuity of an electric vehicle (EV) using a dual induction motor’s structure piloted by Backstepping control. An equivalent induction motor model with turn-to-turn fault on one stator phase, without already assuming the temperature effect through an intrinsic model, is investigated. Afterward,its impacts on electric vehicle performance using simulation tests are presented anddiscussed.
Merdj F, Drid S. Electromagnetic Forces Effects of MHD Micropump on the Blood Movement. Electromagnetic Forces Effects of MHD Micropump on the Blood Movement [Internet]. 2022. Publisher's VersionAbstract

The magnetohydrodynamic pump is an attractive solution, in particular for biomedical applications. In an MHD pump, an electromagnetic force is created by the applied magnetic field, which causes the fluid movement. The main advantage of the MHD pump is there are no mobile (mechanical) parts and it can place directly on veins. The present paper deals with the blood behaviour in the MHD micropump. A neodymium permanent magnet is used for applying a magnetic field to the channel in the MHD micropump. The numerical study examines the influence of the channel dimensions, the flux magnetic density and the electrode potentials on the blood velocity. This micropump can be easily controlled by a low voltage source. The numerical simulation analysis for the adopted model was implemented in order to verify the micropump operation. The magnetic and electrical fields have a strong influence on blood velocity in the MHD micropump. Finite element modelling software was used for this process. The second objective of this work is the possibility to exploit the properties of this pump in hemodialysis to pump blood and cleaning fluid.

Merdj F, Drid S. Electromagnetic Forces Effects of MHD Micropump on the Blood Movement. Electromagnetic Forces Effects of MHD Micropump on the Blood Movement [Internet]. 2022. Publisher's VersionAbstract

The magnetohydrodynamic pump is an attractive solution, in particular for biomedical applications. In an MHD pump, an electromagnetic force is created by the applied magnetic field, which causes the fluid movement. The main advantage of the MHD pump is there are no mobile (mechanical) parts and it can place directly on veins. The present paper deals with the blood behaviour in the MHD micropump. A neodymium permanent magnet is used for applying a magnetic field to the channel in the MHD micropump. The numerical study examines the influence of the channel dimensions, the flux magnetic density and the electrode potentials on the blood velocity. This micropump can be easily controlled by a low voltage source. The numerical simulation analysis for the adopted model was implemented in order to verify the micropump operation. The magnetic and electrical fields have a strong influence on blood velocity in the MHD micropump. Finite element modelling software was used for this process. The second objective of this work is the possibility to exploit the properties of this pump in hemodialysis to pump blood and cleaning fluid.

Boulagouas W, Djebabra M, Chaib R. Contribution to risk assessment: a dynamic approach using Bayesian theory. 1st International Symposium on Industrial Engineering, Maintenance and Safety, March 05-06th. 2022.
Boulagouas W, Djebabra M, Chaib R. Contribution to risk assessment: a dynamic approach using Bayesian theory. 1st International Symposium on Industrial Engineering, Maintenance and Safety, March 05-06th. 2022.
Boulagouas W, Djebabra M, Chaib R. Contribution to risk assessment: a dynamic approach using Bayesian theory. 1st International Symposium on Industrial Engineering, Maintenance and Safety, March 05-06th. 2022.
Fourar Y-O, Benhassine W, Boughaba A, Djebabra M. Contribution to the assessment of patient safety culture in Algerian healthcare settings: The ASCO project. International Journal of Healthcare Management [Internet]. 2022;15 (1) :52-61. Publisher's VersionAbstract
Background A positive Patient Safety Culture (PSC) is considered as the main barrier to adverse events (AEs) that affect healthcare quality and safety. Thus, the assessment of PSC became a priority for healthcare providers in order to identify problematic areas that need improvement actions. Method A cross sectional multi-center study was conducted to evaluate quantitatively PSC in 10 Algerian healthcare establishments (HEs) within the framework of the Algerian Observatory of Safety Culture (ASCO Project). The French version of the HSOPSC was used as a measurement tool where it was administered to participants (N = 1370) using convenience sampling. Results A total of 1118 respondents, all professional categories included, participated in this study. The response rate was estimated at 69% of the sample size (N = 1370). After statistical processing, 950 questionnaires were retained. Internal consistency was above 0.7 for all dimensions. Problematic PSC dimensions were identified, mainly ‘Non-punitive response to error’, ‘Staffing’ and ‘Communication openness’. Conclusions This article sheds light on the critical situation of PSC in the Algerian national health system. Quantitative findings were introduced in the framework of the Algerian Safety Culture Observatory project that will serve as a baseline for different stakeholders to guide long-term promotion actions.
Fourar Y-O, Benhassine W, Boughaba A, Djebabra M. Contribution to the assessment of patient safety culture in Algerian healthcare settings: The ASCO project. International Journal of Healthcare Management [Internet]. 2022;15 (1) :52-61. Publisher's VersionAbstract
Background A positive Patient Safety Culture (PSC) is considered as the main barrier to adverse events (AEs) that affect healthcare quality and safety. Thus, the assessment of PSC became a priority for healthcare providers in order to identify problematic areas that need improvement actions. Method A cross sectional multi-center study was conducted to evaluate quantitatively PSC in 10 Algerian healthcare establishments (HEs) within the framework of the Algerian Observatory of Safety Culture (ASCO Project). The French version of the HSOPSC was used as a measurement tool where it was administered to participants (N = 1370) using convenience sampling. Results A total of 1118 respondents, all professional categories included, participated in this study. The response rate was estimated at 69% of the sample size (N = 1370). After statistical processing, 950 questionnaires were retained. Internal consistency was above 0.7 for all dimensions. Problematic PSC dimensions were identified, mainly ‘Non-punitive response to error’, ‘Staffing’ and ‘Communication openness’. Conclusions This article sheds light on the critical situation of PSC in the Algerian national health system. Quantitative findings were introduced in the framework of the Algerian Safety Culture Observatory project that will serve as a baseline for different stakeholders to guide long-term promotion actions.
Fourar Y-O, Benhassine W, Boughaba A, Djebabra M. Contribution to the assessment of patient safety culture in Algerian healthcare settings: The ASCO project. International Journal of Healthcare Management [Internet]. 2022;15 (1) :52-61. Publisher's VersionAbstract
Background A positive Patient Safety Culture (PSC) is considered as the main barrier to adverse events (AEs) that affect healthcare quality and safety. Thus, the assessment of PSC became a priority for healthcare providers in order to identify problematic areas that need improvement actions. Method A cross sectional multi-center study was conducted to evaluate quantitatively PSC in 10 Algerian healthcare establishments (HEs) within the framework of the Algerian Observatory of Safety Culture (ASCO Project). The French version of the HSOPSC was used as a measurement tool where it was administered to participants (N = 1370) using convenience sampling. Results A total of 1118 respondents, all professional categories included, participated in this study. The response rate was estimated at 69% of the sample size (N = 1370). After statistical processing, 950 questionnaires were retained. Internal consistency was above 0.7 for all dimensions. Problematic PSC dimensions were identified, mainly ‘Non-punitive response to error’, ‘Staffing’ and ‘Communication openness’. Conclusions This article sheds light on the critical situation of PSC in the Algerian national health system. Quantitative findings were introduced in the framework of the Algerian Safety Culture Observatory project that will serve as a baseline for different stakeholders to guide long-term promotion actions.
Fourar Y-O, Benhassine W, Boughaba A, Djebabra M. Contribution to the assessment of patient safety culture in Algerian healthcare settings: The ASCO project. International Journal of Healthcare Management [Internet]. 2022;15 (1) :52-61. Publisher's VersionAbstract
Background A positive Patient Safety Culture (PSC) is considered as the main barrier to adverse events (AEs) that affect healthcare quality and safety. Thus, the assessment of PSC became a priority for healthcare providers in order to identify problematic areas that need improvement actions. Method A cross sectional multi-center study was conducted to evaluate quantitatively PSC in 10 Algerian healthcare establishments (HEs) within the framework of the Algerian Observatory of Safety Culture (ASCO Project). The French version of the HSOPSC was used as a measurement tool where it was administered to participants (N = 1370) using convenience sampling. Results A total of 1118 respondents, all professional categories included, participated in this study. The response rate was estimated at 69% of the sample size (N = 1370). After statistical processing, 950 questionnaires were retained. Internal consistency was above 0.7 for all dimensions. Problematic PSC dimensions were identified, mainly ‘Non-punitive response to error’, ‘Staffing’ and ‘Communication openness’. Conclusions This article sheds light on the critical situation of PSC in the Algerian national health system. Quantitative findings were introduced in the framework of the Algerian Safety Culture Observatory project that will serve as a baseline for different stakeholders to guide long-term promotion actions.
Hadef H, Djebabra M, Boufades D, Belmazouzi Y. Domino effect analysis at a gas facility: Application at a storage facility. Materials today proceedings [Internet]. 2022;49 (4) :925-931. Publisher's VersionAbstract
In the context of the industrial process safety, the domino effect has become a topical issue for scientists and managers of companies given the diversity of factors that contributed to the aggravation of this phenomenon such as; proximity to industrial facilities, transport networks, development of industrial complexes, storage of hazardous substances and population growth. The purpose of this article is the MICDE method (Method of Identification and Characterization of Domino Effects) application on industrial zone of LPG storage in SONATRACH-Algeria Group for analyzes the domino effects caused by a major industrial accident. Our study is adopted on the MICDE method which constitutes an aid in the integration of the domino effects problem in hazard studies and safety studies. In our application, it aims to formalize the points relating to the domino effects due to the BLEVE (Boiling Liquid Expanding Vapor Explosion) phenomenon of an LPG storage sphere. The results obtained show that the hazardous equipment in the vicinity is seriously affected by the thermal and overpressure effect of the main accident, and may be seats in a new accident. The MICDE method is a promising method can be applied in several fields since it studies the phenomenon. This method facilitates decision-making in the prevention of domino effects for the sustainability facilities

Pages