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Turbulent Double-Diffusive Natural Convection and Entropy Generation within an Inclined Square Cavity

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Fluid Dynamics & Materials Processing 2022年第6期18卷 1619-1629页

作者： Khaled said Ahmed Ouadha Amina Sabeur Laboratoire des Sciences et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie Mohamed BOUDIAF d’OranOran El-MnouarAlgérie

The present study deals with double-diffusive convection within a two-dimensional inclined cavity filled with an air-CO_(2) binary gas *** left and the right vertical walls are differentially heated and subjected to different locations of(CO_(2))contaminants to allow for the variation of the buoyancy strength(N).However,the horizontal walls are assumed *** simulations are conducted using the finite volume method to solve the conservation equations of continuity,momentum,energy,and species *** agreement with other numerical results in the literature is *** effect of multiple parameters,namely,buoyancy ratio(N),thermal Rayleigh number(Ra),and inclination angle(α)on entropy generation rate is analyzed and discussed in the postprocessing stage,while considering both laminar and turbulent flow *** computations reveal that these parameters considerably affect both the heat and mass transfer performances of the system.

关键词： CFD entropy generation double diffusive convection inclination angle CO_(2) turbulent regime

Merging control strategies of connected and autonomous vehicles at freeway on-ramps:a comprehensive review

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Journal of Intelligent and Connected Vehicles 2022年第2期5卷 99-111页

作者： Jie Zhu said Easa Kun Gao Department of Architecture and Civil Engineering Chalmers University of TechnologyGothenburgSweden Department of Civil Engineering Ryerson UniversityTorontoCanada

Purpose–On-ramp merging areas are typical bottlenecks in the freeway network since merging on-ramp vehicles may cause intensive disturbances on the mainline traffic flow and lead to various negative impacts on traffic efficiency and *** connected and autonomous vehicles(CAVs),with their capabilities of real-time communication and precise motion control,hold a great potential to facilitate ramp merging operation through enhanced coordination *** paper aims to present a comprehensive review of the existing ramp merging strategies leveraging CAVs,focusing on the latest trends and developments in the research ***/methodology/approach–The review comprehensively covers 44 papers recently published in leading transportation *** on the application context,control strategies are categorized into three categories:merging into sing-lane freeways with total CAVs,merging into singlane freeways with mixed traffic flows and merging into multilane ***–Relevant literature is reviewed regarding the required technologies,control decision level,applied methods and impacts on traffic *** importantly,the authors identify the existing research gaps and provide insightful discussions on the potential and promising directions for future research based on the review,which facilitates further advancement in this research ***/value–Many strategies based on the communication and automation capabilities of CAVs have been developed over the past decades,devoted to facilitating the merging/lane-changing maneuvers at freeway *** the significant progress made,an up-to-date review covering these latest developments is missing to the authors’best *** paper conducts a thorough review of the cooperation/coordination strategies that facilitate freeway on-ramp merging using CAVs,focusing on the latest developments in this *** on the review,the authors identify the existing research gaps in CAV r

关键词： Ramp merging Connected and autonomous vehicles Vehicle coordination Mixed traffic Multilane freeway

Hydrogen FBG Sensor Using Pd/Ag Film With Application in Propulsion System Fuel Tank Model of Aerospace Vehicle

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Photonic Sensors 2014年第3期4卷 254-264页

作者： said SAAD Lotfi HASSINE Vassim ELFAHEM Group of Electronics and Quantum Physics Laboratory of Advanced Materials and Quantum Phenomena Faculty ofSciences of Tunis 2092 Tunisia National Institute of Applied Sciences and Technology University of Carthage North Urban Center of Tunis-B.P. 676Cedex Tunis 1080 Tunisia Regio iT Gesellschaft mit beschrankter Hafiung Aachen Germany

The high efficiency hydrogen fiber Bragg grating （FBG） sensor is presented. The sensitive film was a new alliance of palladium-silver （Pd-Ag）. In addition, the titanium （Ti） layer was used as the adhesive layer. The presented sensor showed the resolution of more than 60pm/1%H2, and a fast response time of4s - 5s was guaranteed in the 0.1%H2 - 4%H2 range. Moreover, the life time of the sensor was investigated. The obtained results showed that the sensor had an enhanced life time. Furthermore, the sensor was applied in the propulsion system fuel tank model of the aerospace vehicle. The obtained results indicated that it is a prevention system against the disaster aerospace due to hydrogen leakage.

关键词： Hydrogen fiber Bragg grating palladium-silver faster response time propulsion system fuel tank prevention system hydrogen leakage

Distribution and Influence of Iron Phases on the Physico-Chemical Properties of Phyllosilicates

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Chinese Journal Of Geochemistry 2001年第2期20卷 120-129页

作者： MERVAT said HASSAN SAYED MAHMOUD SALEM Central Metallurgical Rand DInstitute CairoEgyptPhysics DepartmentFaculty of ScienceAlAzhar UniversityNaserCityCairoEgypt

Clay minerals from different Cretaceous stratigraphic successions of Egypt were investigated using XRD, DTA, dissolution analysis (DCB), IR, Mssbauer and X\|ray Electron Spin Resonance (ESR) spectroscopes. The purity of the samples and the degree of their structural order were determined by XRD. The location of Fe in the octahedral sheet is characterized by absorption bands at ～875cm\+\{-1\} assigned as Al\|OH\|Fe which persist after chemical dissolution of free iron. The Mssbauer spectra of these clays show two doublets with isomer shift and quadrupole splitting typical of octahedrally coordinated Fe\+\{3+\}, in addition to third doublet with hyperfine parameter typical of Fe\+\{2+\} in the spectra of Abu\|Had kaolinite (H) sample. Six\|lines magnetic hyperfine components which are consistent with those of hematite are confirmed in the spectra of both Isel and Rish kaolinite samples. Goethite was confirmed by both IR and DTA. Multiple nature of ESR of these clays suggested structural Fe in distorted octahedral symmetry as well as non\|structural Fe.\; Little dispersion and low swelling indices as well as incomplete activation of the investigated montmorillonite samples by NaCO\-3 appear to be due to incomplete disaggregation of montmorillonite particles. This can be explained by the ability of Fe\|gel to aggregate the montmorillonite into pseudo\|particles and retard the rigid\|gel structure. However, extraction of this ferric amorphous compound by dithonite treatment recovers the surface properties of the montmorillonite samples.\; On the other hand, the amount and site occupation of Fe associated with kaolinite samples show an inverse correlation with the parameters used to describe the degree of crystallinity perfection, color, brightness and vitrification range of these kaolinite samples.

关键词：白垩纪粘土铁相矿物学物理化学特征光谱学

The calculation of band gap energy in zinc oxide films

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Journal of Semiconductors 2015年第1期36卷 17-22页

作者： Ali Arif Okba Belahssen Salim Gareh said Benramache Electrical Engineering Department Faculty of Technology University of Biskra Algeria Laboratoire de Physique des Couches Minces et Applications (LPCMA) Université de Biskra Algeria Mechanical Engineering Department Faculty of Technology University of Biskra Algeria

We investigated the optical properties of undoped zinc oxide thin films as the n-type semiconductor;the thin films were deposited at different precursor molarities by ultrasonic spray and spray pyrolysis *** thin films were deposited at different substrate temperatures ranging between 200 and 500℃. In this paper, we present a new approach to control the optical gap energy of ZnO thin films by concentration of the ZnO solution and substrate temperatures from experimental data, which were published in international journals. The model proposed to calculate the band gap energy with the Urbach energy was investigated. The relation between the experimental data and theoretical calculation suggests that the band gap energies are predominantly estimated by the Urbach energies, film transparency, and concentration of the ZnO solution and substrate temperatures. The measurements by these proposal models are in qualitative agreements with the experimental data; the correlation coefficient values were varied in the range 0.96–0.99999, indicating high quality representation of data based on Equation（2）, so that the relative errors of all calculation are smaller than 4%. Thus, one can suppose that the undoped ZnO thin films are chemically purer and have many fewer defects and less disorder owing to an almost complete chemical decomposition and contained higher optical band gap energy.

关键词： ZnO thin films semiconductor band gap energy correlation

Desertification Detection in Makkah Region based on Aerial Images Classification

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Computer Systems Science & Engineering 2022年第2期40卷 607-618页

作者： Yahia said Mohammad Barr Taoufik saidani Mohamed Atri Electrical Engineering Department College of EngineeringNorthern Border UniversityArarSaudi Arabia Laboratory of Electronics and Microelectronics(LR99ES30) Faculty of Sciences of MonastirUniversity of MonastirTunisia Department of Computer Sciences Faculty of Computing&Information TechnologyNorthern Border UniversityRafhaSaudi Arabia College of Computer Sciences King Khalid UniversityAbhaSaudi Arabia

Desertification has become a global threat and caused a crisis,especially in Middle Eastern countries,such as Saudi *** is one of the most important cities in Saudi Arabia that needs to be protected from *** vegetation area in Makkah has been damaged because of desertification through wind,floods,overgrazing,and global climate *** damage caused by desertification can be recovered provided urgent action is taken to prevent further degradation of the vegetation *** this paper,we propose an automatic desertification detection system based on Deep Learning *** images are classified using Convolutional Neural Networks(CNN)to detect land state variation in *** have been widely used for computer vision applications,such as image classification,image segmentation,and quality *** proposed CNN model was trained and evaluated on the Arial Image Dataset(AID).Compared to state-of-the-art methods,the proposed model has better performance while being suitable for embedded *** has achieved high efficiency with 96.47% *** light of the current research,we assert the appropriateness of the proposed CNN model in detecting desertification from aerial images.

关键词： Desertification detection deep learning convolutional neural networks(CNN) aerial images classification Makkah region

Patterns of genetic and morphometric diversity in the marbled crab(Pachygrapsus marmoratus, Brachyura, Grapsidae)populations across the Tunisian coast

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Acta Oceanologica Sinica 2015年第6期34卷 49-58页

作者： Temim Deli Hiba Bahles Khaled said Noureddine Chatti Laboratory of Genetics Biodiversity and Enhancement of Bioresources (LR11ES41) University of Monastir Higher Institute of Biotechnology of Monastir

The present study reports on population structure analysis of the marbled crab Pachygrapsus marmoratus （Fabricius, 1787） from the Tunisian coast, an appropriate location to study biogeographical processes because of the presence of a well-known discontinuous biogeographic area （the Siculo-Tunisian Strait）. Patterns of morphological and genetic variation of this highly dispersive and continuously distributed decapod species were assessed among its geographically close populations which cover almost the entire Tunisian coastline. A total of 386 specimens from nine sites were collected and examined for morphometric variability at 14 morphometric traits. The results of multivariate analyses of linear morphometric traits showed the existence of sexual dimorphism in this species by PERMANOVA （Permutational multivariate analysis of variance）. In addition, both CDA （Canonical discriminant analysis） and NPMANOVA （Non parametric MANOVA test） analyses revealed statistically significant differences among the studied locations for both sexes. Overall, the outcome of CDA analysis showed that over 87% of individuals could be assigned correctly to three regional groups in both sexes （North, Center and South）. Specifically, SIMPER （Similarity Percentages） analysis showed that carapace length, carapace width and merus length were major contributors to the morphometric separation between populations. The pattern of phenotypic variation suggested by morphometric analyses was found to be highly discordant with that suggested by the analysis of a mitochondrial marker （cytochrome oxidase I, COI）. Indeed, the results inferred from restriction fragment analysis of the COI in 180 crabs, suggested high genetic homogeneity. Very low levels of haplotype diversity （h） were found in almost all the studied populations, associated with non significant genetic distances for nearly all population comparisons. Explanations to these morphometric and mtDNA patterns as well as the discrepancy between the

关键词： Pachygrapsus marmoratus Tunisian coast multivariate analysis morphological differentiation COI genetic homogeneity

Using Sieve of Eratosthenes for the Factor Analysis of Neutrosophic Form of the Five Facet Mindfulness Questionnaire as an Alternative Confirmatory Factor Analysis

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 953-971页

作者： Volkan Duran Selcuk Topal Florentin Smarandache said Broumi Igdır University CampusIgdır76000Turkey Department of Mathematics Arts and Sciences FacultyBitlis Eren UniversityBitlisTurkey Department of Mathematics University of New MexicoGallup87301NMUSA Laboratory of Information Processing Faculty of Science Ben M’SikUniversity Hassan IICasablancaMorocco

In this study,the Five Facet Mindfulness Questionnaire which was adapted from the short form of the Five Facet Mindfulness Questionnaire was evaluated and this scale into neutrosophic form was converted and the results of the scale were compared for proposing new type confirmatory analysis procedure as well as developing neutrosophic *** exploratory factor analysis was used in the analysis of the ***,test results were analyzed for Kaiser–Meyer–Olkin and Bartlett values,common factor variance values,scree plot graphs,and the principal component analysis *** sample of the study consists of 194 students in mathematics departments at Bitlis Eren University and Igdır University in Turkey by convenience sampling method.A convenience sampling is a kind˘of non-probability sampling procedure in which the sample is obtained from a group of individuals easily accessible or *** convenience sampling method was chosen in this study because the study aims to examine the structure of the measurement tool rather than the psychological characteristics of a particular *** of all,it is observed that if any classical scale can be converted into a neutrosophic *** is observed that the sub-dimensions of a neutrosophic scale as agree,disagree,and undecided might not have a similar factor structure to the classical ***,in the factor analysis of the neutrosophic scale,both classical and the agreement part of the neutrosophic scales have the same factors,implying that the one-dimensional classical scale measures the agreement degree of the *** the factor analysis was conducted to disagreement and vagueness dimensions,it seemed that some factors were eliminated and even some new factors emerged,indicating that in human cognition those three dimensions can be taken as independent of each other,just as assumed by neutrosophic *** another important implication of the factor analysis is that the neutrosophic forms

关键词： Neutrosophic scales factor analysis scale development explanatory analysis reliability analysis

Effect of band gap energy on the electrical conductivity in doped ZnO thin film

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Journal of Semiconductors 2014年第7期35卷 19-22页

作者： said Benramache Okba Belahssen Hachemi Ben Temam Physic Laboratory of Thin Films and Applications LPCMA University of BiskraBiskra 07000Algeria

The transparent conductive pure and doped zinc oxide thin films with aluminum, cobalt and indium were deposited by ultrasonic spray technique on glass substrate at 350 ℃. This paper is to present a new approach to the description of correlation between electrical conductivity and optical gap energy with dopants＇ concentration of A1, Co and In. The correlation between the electrical and optical properties with doping level suggests that the electrical conductivity of the films is predominantly estimated by the band gap energy and the concentrations of A1, Co and In. The measurement in the electrical conductivity of doped films with correlation is equal to the experimental value, the error of this correlation is smaller than 13%. The minimum error value was estimated in the cobalt-doped ZnO thin films. This result indicates that such Co-doped ZnO thin films are chemically purer and have far fewer defects and less disorder owing to an almost complete chemical decomposition.

关键词： ZnO thin films semiconductor doping electrical conductivity optical gap energy correlation