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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

Quantitative Uncertainty Principles for the Canonical Fourier-Bessel Transform

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Acta Mathematica Sinica,English Series 2022年第2期38卷 331-346页

作者： Jihed SAHBANI Faculty of Sciences of tunis University of Tunis El Manar2092 TunisTunisia

The aim of this paper is to establish an extension of quantitative uncertainty principles and an algorithm for signal recovery about the essential supports related to a Bessel type of(LCT)so called canonical Fourier-B... 详细信息

关键词： Fourier-Bessel transform linear canonical transform quantitative uncertainty principles Donoho-Stark theorem algorithm for signal recovery

Assessment of self- and cross-absorbed SAF values for HDRK-man using GEANT4 code: internal photon and electron emitters

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Nuclear Science and Techniques 2019年第10期30卷 40-47页

作者： Maroua Bhar Omrane Kadri Kais Manai Higher Institute of Medical Technologies of tunis Tunis El Manar UniversityTunisTunisia Nuclear Physics and High Energy Unit Faculty of Sciences of TunisTunis El Manar UniversityTunisTunisia

The ultimate need to account for the partial amount of energy deposited in target tissue/organ resulting from internal inhalation,ingestion,and injection intakes of radionuclides,defined by the Medical Internal Radiation Dosimetry committee as the specific absorbed fraction(SAF),has become *** this study,we assessed the SAF values for self-and cross-absorption,which were calculated for a uniform distribution of monoenergetic photon and electron emitters with energies ranging from 15 keV to 3 *** voxelized human phantom‘‘High-Definition Reference Korean-man’’(HDRK-man),which was implemented using the Monte Carlo simulation code GEANT4(version 10.1),was used for several combinations of target–source *** results were compared to those of the International Commission on Radiological Protection Reference(ICRP133)and Zubal *** was found that the SAF values of the three models have a similar ***,the SAF values for the HDRK-man phantom were higher than those of the other two models,with a relatively good agreement with those for the ICRP133 phantom(differences of 13.9±2.8 and 12.1±3.2 for photon and electron emitters,respectively).To analyze the differences in SAF values,we calculated the chord length distributions(CLDs)for selected target–source *** parameters of organ mass(or volume)and CLDs,in addition to the adopted computational procedures,mainly cause such *** realistic radionuclide emission spectra,an overall overestimation was observed when computing the S values for three radiopharmaceuticals studied(I-131,In-111,and Lu-177)and for liver–spleen intra-and inter-organ absorption when compared with published *** new arrangement of S and SAF values is expected to add value for multidisciplinary research and clinical communities.

关键词： GEANT4 Monte Carlo simulation Internal dosimetry HDRK-man S and SAF values

Sea-level rise impact on the evolution of a microtidal Mediterranean coastline without human-made structures——a case of the Port aux Princes-Sidi Daoued coastline,Gulf of tunis,NE-tunisia

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Acta Oceanologica Sinica 2019年第3期38卷 72-77页

作者： Hanen Saidi Fouad Zargouni Geology Department Faculty of Sciences of TunisUniversity Tunis El Manar

The evolution of the natural and pristine Mediterranean coastline Port aux Princes-Sidi Daoued(Gulf of tunis,NE-tunisia) is studied during the period of 1887–2010 on the basis of an ancient minute of bathymetry(1887) and aerial photographs treated by numerical photogrammetric methods. Morphological changes of the coastline shows a general retreat despite the absence of the various anthropogenic actions. Adding to the drift currents and the currents of high energy that are generated by the N-W dominant waves along steeply sub-marine funds, the erosion is mainly due to the sea level rise which increased since the beginning of the 2000 s. The Port aux PrincesSidi Daoued coastline works as a single littoral cell limited by Jbel Korbous to the SW and the fishing harbor of Sidi Daoued to the N-E.

关键词： Mediterranean coastline erosion sea level rise littoral cell Gulf of tunis tunisia

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

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

Event-Based Semantics of UML 2.X Concurrent Sequence Diagrams for Formal Verification

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Journal of Computer Science & Technology 2022年第1期37卷 4-28页

作者： Inès Mouakher Fatma Dhaou J.Christian Attiogbé Faculty of Sciences of tunis University of Tunis El Manar1068TunisTunisia Institute of Technology University of Nantes44322NantesFrance

UML 2.X sequence diagrams(SD)are among privileged scenarios-based approaches dealing with the complexity of modeling the behaviors of some current ***,there are several issues related to the standard semantics of UML 2.X SD proposed by the Object Management Group(OMG).They mainly concern ambiguities of the interpretation of SDs,and the computation of causal relations between events which is not specifically laid ***,SD is a semi-formal language,and it does not support the verification of the modeled *** justifies the considerable number of research studies intending to define formal semantics of UML *** proposed in our previous work semantics covering the most popular combined fragments(CF)of control-flow ALT,OPT,LOOP and SEQ,allowing to model alternative,optional,iterative and sequential behaviors *** proposed semantics is based on partial order theory relations that permit the computation of the precedence relations between the events of an SD with nested *** also addressed the issue of the evaluation of the interaction constraint(guard)for guarded CFs,and the related synchronization *** this paper,we first extend our semantics,proposed in our previous work;indeed,we propose new rules for the computation of causal relations for SD with PAR and STRICT CFs(dedicated to modeling concurrent and strict behaviors respectively)as well as their ***,we propose a transformational semantics in *** modeling approach emphasizes computation of causal relations,guard handling and transformational semantics into *** transformation of UML 2.X SD into the formal method Event-B allows us to perform several kinds of verification including simulation,trace acceptance,verification of properties,and verification of refinement relation between SDs.

关键词： UML 2.X sequence diagram formal semantics nested combined fragment partial order theory Event-B

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

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