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Nuclear Science and Techniques 2017年第9期28卷 119-128页

作者： Leila Ounalli Maroua Bhar arbi mejri Kais Manai Ammar Bouabidi Shayma Mohamed Abdallah Nafaa Reguigui Tunisian Center for Nuclear Sciences and Technology Technopark Sidi Thabet 2020 Ariana Tunisia Laboratory on Energy and Matter for Nuclear SciencesDevelopment Technopark Sidi Thabet 2020 Ariana Tunisia Tunisian Higher Institute of Medical Technologies 9 RueZouhair Essafi 1006 TUNIS 1006 Tunis Tunisia Faculty of Sciences of Tunis Technopark Sidi Thabet2020 Ariana Tunisia College of Science and Arts University of Bisha BishaKingdom of Saudi Arabia

To check the dose uniformity and to determine the efficiency of medical devices sterilization by gamma irradiation after three half lives of the source, calculations of the absorbed dose were carried out. Monte Carlo simulations and dosimetry measurements, were established to study the radiation processing quality control. An isodose chart was created by GEANT4 Monte Carlo code to evaluate the absorbed dose rate uniformity inside the irradiation room from the year of the installation until the year of the source reload. The dose uniformity ratio(DUR) is deduced from maximum and minimum experimental doses in medical devices after three half lives of the source.

关键词：剂量测量蒙特卡洛半衰期过程控制辐照模拟钴-60 突尼斯 Geant4

An Approach for Using of Poly Glycolic Acid (PGA) in Reference Standard Dosimetry: PGA/ESR Dosimetry System Response Curve and Post Irradiation Stability

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World Journal of Nuclear Science and Technology 2012年第3期2卷 73-79页

作者： arbi mejri Haikel Jelassi Khaled Farah Ahmad Hichem Hamzaoui Hichem Eleuch Departments of Physics and Astronomy Institute for Quantum Science and Engineering Texas A & M University College Station Texas USA Ionizing Radiation Dosimetry Laboratory National Center for Nuclear Sciences and TechnologiesTunis Tunisia National Institute of Scientific and Technical Research Tunisia Research Unit: Control and Development of Nuclear Technology for Peaceful Uses National Center for Nuclear Sciences and Technologies Tunis Tunisia

Reference Standard Dosimeters are used to calibrate radiation environments and routine dosimeters. It can also be used in routine dosimetry applications for radiation processing where higher quality dosimetry measurements are required. Electron Spin Resonance (ESR) is a well-established Reference Standard Dosimetry system in industrial applications of ionising radiation, and its use is also proposed in radiation therapy and accident dosimetry. In the present experimental work, PGA solid state dosimeter (SSD) has been investigated using ESR spectroscopy to study the gamma radiation response of this material and to evaluate its dosimetric characteristics: dose response, room temperature fading, heat treatment effect during post-irradiation storage. Results obtained up to now confirm that PGA seems to be suitable material for ESR dosimetry applications.

关键词： Dosimetry Solid State Dosimeter (SSD) Poly Glycolic Acid (PGA) Electron Spin Resonance (ESR) Reference Standard Dosimetery Post-Irradiation Thermal Treatments Fading Behaviour

Study of Agar Proportions Effect on a Gamma Ray Synthesized Hydrogel

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材料科学与工程（中英文A版） 2016年第2期6卷 88-100页

作者： Nour Elhouda Ben Ammar Taib Saied arbi mejri Faouzi Hosni Adel Mnif Ahmed HichemHamzaoui Laboratory of Useful Materials Valuation National Center for Research in Materials Sciences Borj Cedria Technopark BP 738027 Soliman Tunisia Laboratory of Analytical Chemistry and Electrochemistry University of Tunis el Manar Science Campus 2092 Tunis Tunisia Treatment Unit by lonizing Radiation National Center of Sciences and Nuclear Technology Sidi Thabet Technopark BP 72 2020Sidi Thabet Tunisia

Aggressive primary hepatic epithelioid hemangioendothelioma:a case report and literature review

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Cancer Biology & Medicine 2017年第2期14卷 187-190页

作者： Mehdi Afrit Meher Nasri Soumaya Labidi Nesrine mejri Houda El Benna Hamouda Boussen Medical Oncology Department Abderahman Mami Hospital

A new case of epithelioid hemangioendothelioma is reported to have occurred to a 67-year-old patient who consulted for rightsided chest pain. The work-up showed multiple right pulmonary lesions associated with bilateral moderate pleural effusion and left-sided pleural thickening and three hypodense nodules in the right lobe of the liver, peritoneal thickening, ascites, and multiple vertebral lytic lesions. The diagnosis of an epithelioid hemangioendothelioma was concluded through a histological examination of a computed tomography scan guided biopsy of the liver. The patient received a primary mono-chemotherapy with Adriamycin(75 mg/m^2 every three weeks) and intravenous bisphosphonates without response and general status impairment. The patient died after 16 months of follow-up.

关键词： Hemangioendothelioma epithelioid metastatic liver treatment

Implantable port thrombosis in cancer patients: a monocentric experience

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Cancer Biology & Medicine 2016年第3期13卷 384-388页

作者： Manel Dridi Nesrine mejri Soumaya Labidi Mehdi Afrit Houda El Benna Khaoula Ben Miled Hamouda Boussen Medical Oncology Department Abderrahmen Mami Hospital Radiology Department Abderrahmen Mami Hospital

Objective: Implantable port thrombosis(IPT) in cancer patients is a relatively rare but severe complication. Several factors are reportedly associated with the occurrence of thrombosis. We aimed to describe the prevalence and the anatomoclinical features of IPT observed in cancer patients who were treated in a medical oncology department in ***: A total of 600 cancer patients who had port implantation from January 2013 to December 2015 were retrospectively identified. Cases with symptomatic/incidental IPT(radiologically confirmed) were further identified. Epidemiological and anatomoclinical features were collected from patient records and the department ***: We observed that 33 of the 600 patients had IPT; thus, the prevalence was 5.5%. The median age was 57 years, and the gender ratio was 0.43. Overweight or obesity was observed in 73% of the patients. IPT occurred mainly in patients with breast(36.4%) and colorectal(33.3%) cancers, which were mostly nonmetastatic(79%). At least one identified classical thromboembolic risk factor was found in 13 patients(smoking in 9, tamoxifen in 2). IPT was symptomatic in 93% of the cases, occurring within an average time of 56 days. Implantable ports were removed because of infection in 2 cases and nonfunctionality in 3 cases. IPT treatment was based on low-molecular-weight heparins(94%) and antivitamin K(6%) for an average of 130 days. Four patients had post-therapy complications: one thrombosis recurrence and three ***: IPT cases in the 600 patients were observed to occur in obese nonmetastatic cancer patients within the first 3 months after IP implantation.

关键词： Implantable port cancer patients thrombosis

Rigorous Electromagnetic Modeling of a Micro Strip Line Incorporating a Flat and Thick Metallic Conductor Based on the Skin Effect Phenomenon

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Open Journal of Metal 2022年第1期12卷 1-9页

作者： Rafika mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

In most studies of microstrip circuits, the majority of researchers assume that the microstrip structures studied have flat metallic conductors of finite widths but without thickness. But in reality these types of structures integrate metallic copper conductors of different thicknesses. If we neglect this thickness we introduce error in the electrical parameters of the microstrip structure, which affects the effective permittivity, the characteristic impedance, the adaptation of the circuit, the resonance frequency, etc. Given the importance of this parameter (thickness of the metal of micro rubon structures), rigorous electromagnetic modeling of the thick micro rubon line based on the skin effect phenomenon (In fact at high frequency the skin effect phenomenon occurs and the current only flows on the periphery of the conductor) has been proposed to improve the studied electric model and ensure the increase in the precision of the analysis method used: Wave concept iterative process. The good agreement between the simulated and published data justifies the improvement of the model.

关键词： Micro Strip Line Thick Conductor WCIP Skin Effect Phenomenon

Modeling of Radiating Aperture Using the Iterative Method

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Detection 2022年第3期9卷 29-36页

作者： Rafika mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

We are interested in this work to electromagnetic leakage, for example the door of the microwave oven (or shielding of electronic functions working in the microwave band containing holes for ventilation circuit) which must be transparent (chain link) but the level of electromagnetic leakage issued by this device must not exceed certain standards. This work started with this article in which we are interested in a simple structure consisting of a multilayer structure incorporating a radiating aperture. We show in this paper mainly the interests of this study and the limitations of using these structures. Modeling of this device is provided by the wave concept iterative procedure (WCIP) which is simple to implement and is characterized by the fast execution method. The validation of our work is carried out by comparing our results with those calculated by the Ansoft HFSS software which shows a good agreement.

关键词： Electromagnetic Leakage Radiating Aperture Microwave Iterative Method Planar Structure Multilayer Electromagnetic Shielding

Incident Detection Based on Differential Analysis

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Journal of Information Security 2024年第3期15卷 378-409页

作者： Mohammed Ali Elseddig Mohamed mejri Computer Science and Information Technology Sudan University of Science and Technology Khartoum Sudan Computer Science Department Laval University Quebec Canada

Internet services and web-based applications play pivotal roles in various sensitive domains, encompassing e-commerce, e-learning, e-healthcare, and e-payment. However, safeguarding these services poses a significant challenge, as the need for robust security measures becomes increasingly imperative. This paper presented an innovative method based on differential analyses to detect abrupt changes in network traffic characteristics. The core concept revolves around identifying abrupt alterations in certain characteristics such as input/output volume, the number of TCP connections, or DNS queries—within the analyzed traffic. Initially, the traffic is segmented into distinct sequences of slices, followed by quantifying specific characteristics for each slice. Subsequently, the distance between successive values of these measured characteristics is computed and clustered to detect sudden changes. To accomplish its objectives, the approach combined several techniques, including propositional logic, distance metrics (e.g., Kullback-Leibler Divergence), and clustering algorithms (e.g., K-means). When applied to two distinct datasets, the proposed approach demonstrates exceptional performance, achieving detection rates of up to 100%.

关键词： IDS SOC SIEM KL-Divergence K-Mean Clustering Algorithms Elbow Method

New Formulation of the Mulilayer Iterative Method: Application to Coplanar Lines with Thick Conductor

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Journal of Electromagnetic Analysis and Applications 2016年第9期8卷 197-218页

作者： Rafika mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University of Tunis El Manar Tunis Tunisia

The skin effect is an electromagnetic phenomenon that makes the current flows only on the surface of the conductors at high frequency. This article is based on the phenomenon to model a structure made in coplanar technology. In reality, these types of structures integrated metal layers of different thickness of copper (9 μm, 18 μm, 35 μm, 70 μm). The neglect of this parameter introduces errors, sometimes significant, in the numerical calculations. This is why an iterative method (FWCIP) based on the wave concept was restated. Validation of results was carried out by comparison with those calculated by Ansoft HFSS software and Agilent ADS Technology. They show a good matching.

关键词： Skin Effect Electromagnetic Phenomenon Iterative Method Coplanar Structure Microwave

A New Approach Based on Iterative Method for the Characterization of a Micro-Strip Line with Thick Copper Conductor

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Journal of Electromagnetic Analysis and Applications 2016年第5期8卷 95-108页

作者： Rafika mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

In this work, we applied two electromagnetic models for the characterization of a planar structure including a flat, thick copper conductor. Indeed the first model is consisted by modeling two metal ribbons without bulkiness, placed one above the other at a distance of h2 equal to the thickness of the thick conductor. This approach has been implemented and tested by the iterative method. The results of simulations have been compared with those calculated by the Ansoft HFSS software, and they are in good concordance, validating the method of analysis used. The second model is based on the calculation of the effective permittivity of the medium containing the thick conductor. This medium consists of a metallic region of complex relative permittivity , the rest of this medium is filled with air er2 = 1. The effective permittivity eeff calculated from these two relative permittivity er2 and . Comparing the simulation results of this new formulation of the iterative method with those calculated by the software Ansoft HFSS shows that they are in good matching which validates the second model.

关键词： Thick Conductor Iterative Method Micro-Strip Line Microwaves Skin Effect Phenomenon Effective Permittivity