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ON THE FINITE MelLIN TRANSFORM IN QUANTUM CALCULUS AND APPLICATION

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Acta Mathematica Scientia 2018年第4期38卷 1393-1410页

作者： Bochra NEFZI Kamel BRAHIM Ahmed FITOUHI Faculty of Sciences of Tunis University of Tunis El Manar

The aim of the present paper is to introduce and study a new type of q-Mellin transform [11], that will be called q-finite Mellin transform. In particular, we prove for this new transform an inversion formula and q-convolution product. The application of this transform is also earlier proposed in solving procedure for a new equation with a new fractional differential operator of a variational type.

关键词： q-Mellin transform finite Mellin transform fractional q-integral fractionalq-differential equation

Energetic Analysis and Working Fluids Selection for a New Power and Refrigeration Combined Ecological System

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Journal of Thermal Science 2022年第6期31卷 2032-2050页

作者： Noureddine TOUJANI Nahla BOUAZIZ Lakder KAIROUANI Tunis El Manar University Energy and Environment Research UnitNational School of Engineers of Tunis1002Tunisia

The main purpose of this study is to analyze the performance of a new system that combines organic Rankine Cycle(ORC) and vapor compression refrigeration cycle(VCRC) for refrigeration and cogeneration. This system uses low-temperature heat sources such as solar energy, geothermal, industrial waste heat and biomass. The novelty of the proposed system manifests itself essentially in: the development of new ORC-VCRC combination architecture, lowering the ORC condensing temperature, the possibility of refrigeration production by the ORC upstream of the pumping phase, preheating of ORC using VCRC fluid and new configurations based on the integration of heat recovery systems to improve the overall system performance. The first part of this study presents the energetic analysis for the basic system using different working fluids and investigation of the operating parameters effect on the system performance(The system performance is described by the ORC thermal efficiency, the VCRC coefficient of performance and the system overall efficiency). Ten working fluids have been selected in order to provide the most adequate candidates for the proposed system. The results showed that the heating temperature and the cooling temperature have a significant effect on the system performance. The choice of fluid was also mentioned;the obtained results confirmed that the best combination for the basic system is R236fa-acetone. Four system configurations are developed and analyzed in the second part of the study. Also in the same part of the study, we will compare these configurations in terms of the performance rate retained. In the last part, we will make a comparison of this new system with another system.

关键词： combined cycle working fluids organic Rankine cycle vapor compression cycle

A BIFURCATION PROBLEM ASSOCIATED TO AN ASYMPTOTICALLY LINEAR FUNCTION

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Acta Mathematica Scientia 2016年第6期36卷 1731-1746页

作者： Soumaya SAANOUNI Nihed TRABelSI Department of Mathematics Faculty of Sciences of TunisUniversity of Tunis El Manar Higher Institut of Medicals Technologies of Tunis University of Tunis El Manar

We study the existence of positive solutions to a two-order semilineav elliptic problem with Dirichlet boundary condition（Pλ）{-div（c（x）△u=λf（u）inΩ,u=0 on ЭΩ where ΩCR n 〉 2 is a smooth bounded domain; f is a positive, increasing and convex source term and c（x） is a smooth bounded positive function on Ω, We also prove the existence of critical value and claim the uniqueness of extremal solutions.

关键词： extremal solution regularity bifurcation stability

Does the Internal Audit Function Play a Role in Mitigating Earnings Management?

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Journal of Modern Accounting and Auditing 2024年第1期20卷 20-38页

作者： Hella Dellai Tunis El Manar University TunisTunisia

This paper aims to investigate the effect of the characteristics of the internal audit function(IAF)on earnings management(EM)for a sample of 27 Tunisian listed companies.The authors employed the Correlated Panels Corrected Standard Errors model to estimate the regression equation.The results showed that EM is negatively associated with internal audit effectiveness,frequency of audit committee meetings with Chief Audit Executives(CAEs),the partial outsourcing of internal audit,and the firm’s size.Moreover,the authors found a positive relationship between EM and the use of IAF as a training ground for management and the private sector.This study is important to academics,regulators,and policymakers in introducing new governance reforms to strengthen the IAF as an important internal governance mechanism to reduce earnings management practices in emerging countries.The results also provide useful information for investors to examine the effect of internal audit characteristics on earnings management.

关键词： earnings management internal audit emerging economies

TWO DIMENSIONAL MelLIN TRANSFORM IN QUANTUM CALCULUS

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Acta Mathematica Scientia 2018年第2期38卷 546-560页

作者： Kamel BRAHIM Latifa RIAHI Faculty of Sciences of Tunis. university of Tunis el manar Tunisia

In this article, we introduce the two dimensional Mellin transform M4（f）（s,t）, give some properties, establish the Paley-Wiener theorem and Plancherel formula, present the Hausdorff-Young inequality, and find seve... 详细信息

关键词： Quantum calculus Two dimensional Mellin transform q-Double integral

SINGULAR LIMIT SOLUTIONS FOR 2-DIMENSIONAL elLIPTIC SYSTEM WITH SUB-QUADRTATIC CONVECTION TERM

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Acta Mathematica Scientia 2018年第4期38卷 1174-1194页

作者： Nihed TRABelSI Higher Institute of Medicals Technologies of Tunis University of Tunis El Manar

The existence of singular limit solutions are investigated by establishing a new Liouville type theorem for nonlinear elliptic system with sub-quadratic convection term and by using the nonlinear domain decomposition ... 详细信息

关键词： Liouville type system singular limit solution nonlinear domain decompositionmethod

Comparison of Essential Oil Composition,Phenolic Compound and Biological Activities of Salvia microphylla and Teucrium polium(Lamiaceae)

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Journal of Renewable Materials 2022年第6期10卷 1607-1621页

作者： Ayda Khadhri Chedia Aouadhi Eric Masson Antonio Pizzi Plant Soil and Environment Interactions LaboratoryFaculty of SciencesUniversity of El-Manar IITunisTunisia Bacteriology and Biotechnology Development Groups Epidemiology Laboratory and Veterinary MicrobiologyPasteur Institute of TunisUniversity of El-Manar IITunisTunisia CRITTBois EpinalFrance LERMAB University of LorraineEpinalFrance Department of Physics King Abdulaziz UniversityJeddahSaudi Arabia

Salvia microphylla and Teucrium polium are medicinal and aromatic plants with ethnobotanical uses.The present study was conducted to investigate the chemical composition of Salvia microphylla and Teucrium polium essential oils,the secondary metabolites,and the biological activities of their infusion and methanolic(MeOH)extracts.Essential oils were extracted by hydrodistillation from shoots Salvia microphylla and Teucrium polium.Phenolic content,antioxidant and antimicrobial activities were determined.Gas chromatography-mass spectrometry(GCMS)results showed the presence of significant qualitative and quantitative variations for the composition of the both essential oils(EO).Salvia microphylla EO were most complex and present 70 compounds with the major components wereβ-caryophyllene(13.32%),1,8 cineole(11.25%),Cis p-Menthane-3-one(10.74%),andβ-Selinenol(9.71%).Where in the Teucrium polium EO,45 compounds were identified with the important components areβ-cadinene(10%),β-citronellol(8.5%),Carvacrol(7.63%),and Eugenol(7.15%).Obtained results showed that both plant are very rich in secondary metabolites.Extracts isolated from Salvia microphylla presented the highest contents in the phenolic compound than extracted from Teucrium polium.The antioxidant activity data demonstrated that all extracts showed strong antioxidant and radical scavenging activities.Essential oil and methanol extracts presented a potential for antimicrobial activities against all tested microorganisms.The obtained results highlight the potential use of Salvia microphylla and Teucrium polium as possible natural antioxidant substances and sources of bioactive molecules.

关键词： Salvia microphylla Teucrium polium phenolic compounds antioxidant antimicrobial activity essential oil

Hourly and monthly variations in the surface activity patterns of Hemilepistus reaumurii in arid environments of Tunisia

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Journal of Arid Land 2018年第3期10卷 470-481页

作者： Anas AYARI Moez TOUIHRI Chedlia GHEMARI Karima NASRI-AMMAR Research Unit of Bio-Ecology and Evolutive Systematics Faculty of Sciences of Tunis University of Tunis El Manar

Life in desert ecosystems drives animals to adapt their surface locomotor activity according to environmental conditions. In this study, the hourly and monthly variations in the surface activity patterns of the terrestrial crustacean Hemilepistus reaumurii were investigated. The surface activity of H. reaumurii at the population scale was observed by collecting the hourly active individuals from the sunrise to the sunset of the studied day in each month of 2013 in the Bchachma locality, Tunisia. The collected active individuals were put in perspex boxes（on which we labeled the hourly time interval in which the individuals were collected） in the field and then transported to the laboratory for analysis. Individuals were counted, sexed, and measured in the laboratory. Despite desert conditions in the studied site, H. reaumurii was characterized by a diurnal surface activity, showing a bimodal pattern during the warm months（i.e., May to October）. However, it exhibited a unimodal surface activity pattern in the cold months（i.e., February, March, and November）. The surface activity was significantly correlated with sunrise and sunset. Moreover, a significant quadratic effect of temperature on the surface activity of H. reaumurii was observed. Furthermore, the study showed that the most important surface activity was recorded in March. The daily exploitation of the temporal niches was significantly different as a function of months. The body size of males was larger than that of females, and the body size of active individuals changed with months. All these behavioural changes in the surface activity represent an adaptive strategy of life in the arid environment.

关键词： diurnal activity variation pattern aboveground activity desert isopod temporal niche Hemilepistus reaumurii Tunisia

The Study of the Behaviors of Zinc and Strontium in Caries-Affected Teeth by Laser-Induced Breakdown Spectroscopy(LIBS) Technique

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光谱学与光谱分析 2020年第3期40卷 980-984页

作者： R.Nouir S.Hamzaoui H.Ghalila N.Ja dane Faculty of Sciences of Tunis University of TunisEl ManarTunisTunisia Institute of Medical Technologies of Tunis University of Tunis El ManarTunisTunisia

We report on the application of Laser Induced Breakdown Spectroscopy(LIBS)technique to the study of Ca,P,Zn and Sr evolutions for adult caries-affected teeth using nanosecond laser pulses.The aim of this work is to better understand the behaviors of Zn and Sr as trace-elements in the caries eruption with respect to the behaviors of one of the main compounds of the hydroxyapatite crystal which is the calcium.The study was focused on the investigation of these elements’evolutions from three parts of the enamel surfaces of twenty two adult caries-affected teeth;the healthy part,the dental plaque part and the caries-affected part.The decrease rates of Zn,Sr and P was,also,compared to the Ca one.Comparison concerned normalized emission line intensities.For every species,normalization was done relatively to the emission line intensities of the healthy part.Results showed that abundances of these elements decrease similarly from the healthy parts to the affected-caries parts.The higher decrease rate was noticed for the calcium.The evolutions of Zn and Sr for the three parts of the teeth surfaces cannot inform about the substitution of the calcium by these trace-elements,however the comparison of their decrease rates to the calcium one can be considered as a valuable index of this substitution.

关键词： Teeth Caries Trace-elements Substitution LIBS