Empathic Modelling for Product Design Engineering Students

( Ibrahim,N. I. ) 한국감성과학회 2014 춘계학술대회 Vol.2014 No.-

This paper explains the use of empathic modelling as a pedagogical tool for Product Design Engineering students. The objective is to expose students to the challenges of being physically impaired when using products. The method that had been used include using low technology props and focusing on simulating people with multiple disabilities. Based on students` responses, it can be concluded that empathic modelling has helped students to gain better understanding the difficulties that older and disabled people usually encounter when carrying out daily tasks. Finally, several issues and challenges related to the use of empathic modelling method are discussed. It is hope that this paper will be valuable for those interested in using empathic modelling in teaching Product Design Engineering.

Valley splitting and enhanced anomalous Hall effect in Mn impurity doped WS₂/CrGeSe₃ heterostructure

Brahim Marfoua,Jisang Hong 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.1

Valleytronics (valley-dependent electronics) is attracting extensive research effort for next generation potential device applications [1-3]. Mostly, the lifting of valley degeneracy was achieved by the incorporation of the magnetic layer induced the proximity effect or the magnetic impurity doping effect. However, it is rare to find reports regarding the valley splitting induced by impurity doping combined with the proximity effect. Thus, we investigated the possibility of enhancing the valley splitting and anomalous Hall conductivity by the combination of two methods in WS2/CrGeSe₃ heterostructure. In the pure WS2/CrGeSe₃ heterostructure, we obtained a small valley splitting of 1 meV at K<SUP>+</SUP> and K<SUP>-</SUP> valleys due to the weak hybridization between the WS2 and CrGeSe₃ layers. However, we obtained a large valley splitting of 68 meV in the Mn impurity doped WS2/CrGeSe₃ heterostructure owing to the Mn doping effect and also the K valley dependent proximity effect. Consequently, this led to a sizable difference in the out-of-plan Berry curvature. We obtained anomalous Hall conductivity (AHC) of 110 S/cm in the Mn doped WS2/CrGeSe₃ system, and this is 20 times larger than that found in the pristine WS2/CrGeSe₃ heterostructure. Our results may provide a new platform through the combination of the two approaches for potential valleytronics applications.

Financial Openness and Growth in Developing Countries: Why Does the Type of External Financing Matter?

Brahim Gaies,Mahmoud-Sami Nabi 세종대학교 경제통합연구소 2019 Journal of Economic Integration Vol.34 No.3

This study examines how external financing (EF) affects growth in developing countries by distinguishing between two forms of external financing: debt and foreign direct investment (FDI). We show that both types favor growth by boosting investment through the credit channel. However, excessive external debt increases vulnerability to financial crises. Contrariwise, FDI plays an amortizing role by reducing a crisis’ effects. The empirical evidence confirms these results and demonstrates that, despite the more secure nature of FDI, mixed financing (debt and FDI) remains more profitable for developing countries because of the inverted U-shaped growth effect of the FDI-to-debt ratio. Moreover, exchange rate stability decreases vulnerability to financial crises, whereas higher stability turns into exchange rate rigidity and thus increases crisis occurrence.

Lithological and Structural Lineament Mapping from Landsat 8 OLI Images in Ras Kammouna Arid Area (Eastern Anti-Atlas, Morocco)

Brahim Es-Sabbar,Mourad Essalhi,Abdelhafid Essalhi,Hicham Si Mhamdi 대한자원환경지질학회 2020 자원환경지질 Vol.53 No.4

The study area is located in the southern part of the M’aider Paleozoic basin in the Moroccan Eastern Anti-Atlas. It is an arid region, characterized by minimal vegetation cover, which can provide an ideal environment to apply remote sensing. In this study, remote sensing and field investigations were integrated for lithological and structural lineaments mapping. The Landsat 8 OLI data were processed in order to understand the role of lithology and geological structures in the distribution of mineral deposits in the study area. To achieve this purpose, the Color Composite (CC), the Principal Component Analysis (PCA) and Band Rationing transformation (BR) tests were performed. The results of remote sensing techniques coupled with field investigations have shown that the zones of high lineaments densities are highly correlated with the occurrences of barite mineralization. These findings depict a spatial relationship between structural lineaments and the mineralization distribution zones. Therefore, the barite and Iron oxides mineralization veins, which occur mainly in the Ras Kammouna district, seem to have a structural control. The methodological approach used in this study examining lithological mapping and lineament extractions can be used to explore mineral deposits in arid regions to a high degree of efficiency.

Electric field dependent valley polarization in 2D ferromagnetic WSe₂/CrSnSe₃ heterostructure

Brahim Marfoua,Jisang Hong 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.1

Along with the traditional charge and spin degree of freedom physical quantities, another physical quantity namely valley state has been introduced as a new degree of freedom that can be utilized for future quantum information storage devices [1]. The valleytronics (valley-dependent electronics) in van der Waals two-dimensional (2D) heterostructures is receiving extensive research efforts. Thus, we investigated the electric field-induced valley polarization in the WSe₂/CrSnSe₃ heterostructures by varying the stacking order. The heterostructure shows indirect band gaps of 270 and 330 meV in the two most stable structures. The WSe₂/CrSnSe₃ heterostructure displays a ferromagnetic ground state with out-of-plane anisotropy (0.02 meV) in one stable stacking (S-1) while a small in-plane anisotropy (-0.01 meV) is found in other stacking (S-2). The Curie temperature is slightly enhanced to 73 K compared to the monolayer CrSnSe₃. We have found the valley splitting of 4 meV in S-1whereas it became 9 meV in the S-2 system. The valley splitting is further enhanced if an electric field is applied from CrSnSe₃ to the WSe₂ layer whereas it is suppressed in the reversed electric field. Particularly, the S-2 structure shows a giant valley splitting of 67 meV at an electric field of 0.6 V/Å. We attribute this electric field-dependency to the dipolar effect. Overall, our findings may imply that the WSe₂/CrSnSe₃ heterostructure can be a potential structure for obtaining a giant valley splitting.

Analysis of edge defects in an elastic plate using SH-waves

Brahim Mohammedi,Nahil A Sobh,Diab Abueidda,Belgacem-Bouzida Aissa 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.1

The interaction of guided SH-waves with the beveled free end of a semi-infinite plate is analytically and numerically investigated. The material of the plate is assumed to be elastic, homogenous, and isotropic. The plate is modeled as a combination of a semi-infinite region and bounded wedged region separated by a common boundary. The analytical solution of the vertical free end case for the two regions is derived and used in verifying the numerical implementation. In this study, the SH 0 and the SH 1 first two incident modes are individually applied to analyze the corresponding reflected modes from the free end. Specifically, the elastic energy carried by the reflected modes is reported for a wide range of beveled angles and incident frequencies.

Exponential growth for a fractional differential equation

BRAHIM TELLAB,KAMEL HAOUAM 장전수학회 2017 Advanced Studies in Contemporary Mathematics Vol.27 No.3

This paper concerns the exponential growth of solutions for a fractional differential equation with a fractional damping of order between 0 and 1 in the presence of a source of polynomial type.

Magnetic Anisotropy of Pd/Co/Pd Ultrathin Film: Interface Vacancy Defect and O Diffusion Effect

Brahim Marfoua,Jisang Hong 한국자기학회 2021 Journal of Magnetics Vol.26 No.3

Using first principles calculation, we investigated the magnetic anisotropy of Pd/Co/Pd ultrathin film. Here, we explored the magnetic anisotropy of pristine Pd/Co/Pd ultrathin film and also interface vacancy defect (Pd or Co) and the oxygen diffusion as well. No substantial change in the magnetic moment is found in the vacancy defect and also in the O diffusion structure relative to the pristine system. We found that the pristine Pd/Co/Pd system has a perpendicular magnetic anisotropy of 1.37 meV/cell. This perpendicular magnetic anisotropy decreased to 0.46 meV/cell in Pd vacancy defect and it became 0.56 meV/cell in Co vacancy defect. We also obtained similar magnetic anisotropy energy of 0.52 meV/cell in the O impurity system. Although the vacancy defect and O impurity system exhibited a similar magnetic anisotropy, we found that this feature originated from different spin-orbit coupling effect which is sensitive to the sample preparation condition.

Optical Properties of a Two-Dimensional GeTe Layer

Brahim Marfoua,홍지상 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.76 No.3

Using the first principles calculations, we explored the optical properties of the two-dimensional -GeTe structure. The 2D monolayer -GeTe had an indirect band gap of 1.79 eV, and that indirect band gap was still observed in the bilayer although the band gap had decreased to 0.61 eV. We found that the optical band gap was much larger than the electrical band gap, which was due to the indirect band gap feature of the 2D -GeTe system. In both systems, we found a very large refractive index in the visible range. Particularly, the bilayer system had a refractive index larger than 2.5 for blue light. Furthermore, the bilayer structure was found to have a larger reflectivity at ultraviolet frequencies. Consequently, we propose that the bilayer -GeTe film can be utilized for potential optical device applications.

Electric filed dependent valley polarization in 2D WSe₂/CrGeTe₃ heterostructure

Brahim Marfoua,Jisang Hong 한국자기학회 2020 한국자기학회 학술연구발표회 논문개요집 Vol.30 No.2