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High density thermite mixture for shaped charge ordnance disposal

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Defence Technology（防务技术） 2017年第5期13卷 376-379页

作者： Tamer elshenawy salah Soliman Ahmed Hawass Technical Research Center Cairo Egypt

The effect of thermite mixture based on aluminum and ferric oxides for ammunition neutralization has been studied and tested. Thermochemical calculations have been carried out for different percentage of Al using Chemical Equilibrium Code to expect the highest performance thermite mixture used for shaped charge ordnance disposal. Densities and enthalpy of different formulations have been calculated and demonstrated. The optimized thermite formulation has been prepared experimentally using cold isostatic pressing technique, which exhibited relatively high density and high burning rate thermite mixture. The produced green product compacted powder mixture was tested against small caliber shaped charge bomblet for neutralization. Theoretical and experimental results showed that the prepared thermite mixture containing 33% of aluminum as a fuel with ferric oxide can be successfully used for shaped charge ordnance disposal.

关键词： Chemical Equilibrium Code which exhibited relatively high density

The Effect of Atrial Septal Defect Closure on Cardiac Volumetric Changes in Adults, Transcatheter Versus Surgical Closure, a Pilot Cardiac Magnetic Resonance Study

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Congenital Heart Disease 2023年第6期18卷 679-691页

作者： Amr Mansour Noha M.Gamal Alaa M.Nady Amr Ibraheem Dalia M.salah Khaled M.el-Maghraby Cardiology Department Congenital and Structural Heart Disease UnitAin Shams University HospitalsFaculty of MedicineAin Shams UniversityCairoEgypt Cardiology Department Faculty of MedicineAssuit UniversityAssuitEgypt Cardiothoracic Surgery Department Faculty of MedicineAssuit UniversityAssuitEgypt Anesthesia Department Faculty of MedicineAssuit UniversityAssuitEgypt

Background:Closure of an atrial septal defect(ASD)reduces right-side heart volumes by abolishing shunting with simultaneous improvement of the left ventricle(LV)ﬁlling and functions due to ventricular interdependence,thereby improving ***,studies conducted on atrial volume changes after ASD closure are *** magnetic resonance(CMR)is considered as the gold standard method for measuring cardiac volume and ***:We aimed to study the effect of transcatheter and surgical closure of secundum ASD on cardiac volumes and systolic functions as well as the fate of tricuspid regurgitation(TR),using CMR ***:We prospectively enrolled 30 adult patients with isolated secundum ASD who were referred to ASD *** evaluation of cardiac chambers indexed volumes,systolic function,myocardial mass index,and tricuspid regurgitant fraction were done at before and 6 months after ***:RV volumes decreased in both groups when compared to baseline(p-value 0.001),the device group had more reduction in volumes and more improvement in RV function after closure(p-value 0.001)when compared to the surgical *** changes in the RV mass index were insigniﬁcant between both groups(p-value 0.31).Functional TR improved to the same extent in both *** ventricular end diastolic volume index(LVEDVI)and LV mass index increased sig-niﬁcantly in both groups when compared to baseline in both groups but with no difference between groups p-value 0.01),left ventricular end systolic volume index(LVESVI)changes were insigniﬁ*** systolic function improved in patients who underwent device closure only(63.53±3.85 vs.67.13±4.34,p-value 0.01).There was a signiﬁcant reduction in right atrial(RA)volumes and an insigniﬁcant decrease in left atrial(LA)volumes,with no difference between ***:Transcatheter and surgical secundum ASD closure resulted in volumetric changes in some cardiac chambers with better improvement in bi-ventricular

关键词： Atrial septal defect closure cardiac volumetric changes functional tricuspid regurgitation cardiac CMR

Multi-sensor Data Fusion for Wheelchair Position Estimation with Unscented Kalman Filter

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International Journal of Automation and computing 2018年第2期15卷 207-217页

作者： Derradji Nada Mounir Bousbia-salah Maamar Bettayeb LASA laboratory Department of Electronics Faculty of Engineering Badji Mokhtar Annaba University Department of electrical and Computer Engineering College of Engineering University of Sharjah

This paper investigates the problem of estimation of the wheelchair position in indoor environments with noisy mea- surements. The measuring system is based on two odometers placed on the axis of the wheels combined with a magnetic compass to determine the position and orientation. Determination of displacements is implemented by an accelerometer. Data coming from sensors are combined and used as inputs to unscented Kalman filter （UKF）. Two data fusion architectures： measurement fusion （MF） and state vector fusion （SVF） are proposed to merge the available measurements. Comparative studies of these two architectures show that the MF architecture provides states estimation with relatively less uncertainty compared to SVF. However, odometers measurements determine the position with relatively high uncertainty followed by the accelerometer measurements. Therefore, fusion in the navigation system is needed. The obtained simulation results show the effectiveness of proposed architectures.

关键词： Data fusion unscented Kalman filter (UKF) measurement fusion (MF) navigation state vector fusion (SVF) wheelchair.

Paving the Way for Economically Accepted and Technically Pronounced Smart Radio Environment

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China Communications 2022年第8期19卷 247-266页

作者： Mostafa salah Andreas Pitsillides Ahmed S.Mubarak Department of electrical Engineering Sohag UniversitySohagEgypt Department of Computer Science University of CyprusNicosiaCyprus Visiting Professor University of JohannesburgDepartment of Electrical and Electronic Engineering ScienceJohannesburgSouth Africa Department of electrical Engineering Aswan UniversityAswanEgypt

Recently,Reconfigurable Intelligent Surfaces(RISs)have been introduced to provide the necessary flexibility for the design of the Smart Radio Environment(SRE),which can be optimally shaped to facilitate efficient signal *** line with the concept of smart cities,SRE needs to be carefully designed with respect to the city infrastructure and utilization of *** this paper,we provide our vision on RIS integration into future Smart Cities by highlighting the potential technical,environmental,and economic motivations of RIS deployment in harmony with various ecosystems at a city level such as buildings *** this end,we are pointing out some scenarios for mitigating the conflict between RIS realization and the existing building facade’s ecosystems such as advertising display and solar cells on building ***,in this fashion,the proposed vision supports a win-win relationship between all stakeholders of different *** study presents guidelines for not only enabling seamless economically accepted RIS widespread utilization but,also more technically sounding SRE by supporting enhanced RIS features and more advanced applications that cannot be attained by traditional passive ***,based on the current research directions,we offer promising insights for cost-effective mass pro-duction through motivating two scenarios of“all on silicon”and“all as metasurface”fabrication *** this study,we aim to encourage the metasurface researchers,that for a broad deployment of the technical solution,economic,environmental,and other commercial requirements should be planned together,early on in the design phase.

关键词： smart radio environment(SRE) reconfigurable intelligent surface(RIS) 6G passive/active metasurface

A New Non-centrosymmetric Microporous Fluorinated Iron Phosphate： Structural elucidation, Spectroscopic Study and Hirshfeld Surface Analysis

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Chemical Research in Chinese Universities 2016年第4期32卷 519-526页

作者： Nabaa BOUZIDIA Besma HAMDI Abdelhamid BEN salah Laboratory of Materials Science and Environment Faculty of Sciences of Sfax University of Sfax PB 1171 3000 SFAX Tunisia

The crystal structure of a new non-centrosymmetric microporous fluorinated iron phosphate, （H30）2[Fe4（H2O）2F4（PO4）2（HPO4）2]（H2O）, was determined by single crystal X-ray diffraction analysis and the result reveals that it belongs to the orthorhombic system with four molecules in the unit cell（space group P212121）. Thus, the complex was characterized by powder X-ray diffraction, spectroscopic techniques（Fourier transform infrared and Fourier transform Raman） and 19F MAS NMR. The elemental analysis of the sample was also carried out. The chiral inorganic sheets, which stacked along [100] showed the presence of FeF2O4 as well as FeF2O3H2O octahedra, PO4 besides HPO4 tetrahedra, hydronium ions（H3O＋） and isolated water molecules. Hirshfeld surface analysis, especially dnom surface and fingerprint plots, were used for decoding the intermolecular interactions in the crystal network and the contribution of component units for the construction of the 3D architecture. From the Hirshfeld surfaces and 2D fingerprint analysis, it was found that the subtle interactions, such as H...H associating the third intense interaction of all intercontacts, provide extra stabilization in addition to the presence of the strong hydrogen bonds mentioned above.

关键词： Non-centrosymmetric structure Iron fluorinated phosphate Hirshfeld surface analysis

Influence of electric current intensity on the performance of electroformed copper liner for shaped charge application

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Defence Technology（防务技术） 2017年第6期13卷 439-442页

作者： Tamer elshenawy salah Soliman Ahmed Hawwas Technical Research Center CairoEgypt

electrolytic Copper used in the shaped charge liner manufacturing can be produced from acid solution using electro-deposition technique. The intensity of the applied electric current controls the quality of the produced copper grade. The electric current intensity within the electrolytic acidic solution cell with the minimum oxygen and sulfur elements in the produced copper was optimized and found to be 30-40 A/Ft^2. The elemental composition of the obtained electrolytic copper was determined using highend stationary vacuum spectrometer, while the oxygen was determined precisely using elTRA ONH-2000 apparatus. Besides, SEM was used to investigate the shape of the copper texture inside the deposited layers and to determine the average grain size. New relations have been obtained between the applied current intensity and both the oxygen and sulfur contents and the average grain size of the produced copper. Experimental result showed that when the applied current density increases to a certain limit, the oxygen and sulfur content in the electrolytic copper decreases. Performance of the produced copper liner was investigated by the static firing of a small caliber shaped charge containing an electro-formed copper liners, where the penetration depth of the optimized electrolytic liner was enhanced by 22.7% compared to that of baseline non-optimized liner.

关键词： electrolytic Copper SEM was used to investigate the shape of the copper texture

Testing the validity of the Ehrenfest theorem beyond simple static systems: Caldirola–Kanai oscillator driven by a time-dependent force

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Chinese Physics B 2016年第8期25卷 15-20页

作者： Salim Medjber Hacene Bekkar salah Menouar Jeong Ryeol Choi Department of Material Science Faculty of Science University of M’sila Faculty of Technology University of Ferhat Abbas Setif 1 Laboratory of Optoelectronics and Compounds (LOC) Department of Physics Faculty of Science University of Ferhat Abbas Setif 1 Department of Radiologic Technology Daegu Health College

The relationship between quantum mechanics and classical mechanics is investigated by taking a Gaussian-type wave packet as a solution of the Schr o¨dinger equation for the Caldirola–Kanai oscillator driven by a sinusoidal force. For this time-dependent system, quantum properties are studied by using the invariant theory of Lewis and Riesenfeld. In particular,we analyze time behaviors of quantum expectation values of position and momentum variables and compare them to those of the counterpart classical ones. Based on this, we check whether the Ehrenfest theorem which was originally developed in static quantum systems can be extended to such time-varying systems without problems.

关键词： Ehrenfest theorem time-dependent Hamiltonian system invariant theory

μPMU-based smart adaptive protection scheme for microgrids

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 887-898页

作者： Mohamed salah elBANA Nabil ABBASY Ashraf MEGHED Nahil SHAKER electrical Engineering Department Faculty of EngineeringAlexandria UniversityLotfy El-Sied St.P.O.ElhadaraAlexandria 21544Egypt

The concepts of microgrids(MGs)and smart grid represent the recent targeted revolution towards fully smart electrical network integrated with high penetration of renewable energy sources(RESs).The protection system of MGs becomes a challenge due to variable characteristics of its currents,bidirectional power flow and output power fluctuations of RES,causing selectivity and sensitivity issues for conventional protective devices(PDs)with fixed *** this paper,a smart protection scheme(SPS)is proposed using micro-phasor measurement units(μPMUs)to obtain the continuous rapid synchronized phasor measurement *** it is communicated with a microgrid central controller(MGCC)through highly reliable communication architecture to carry out online smart adaptive protection *** index coefficients and abnormality coefficients are calculated for each feeder to detect the fault location and the abnormality *** modeling of an MG including 10-bus connected distribution system with integrated distributed generation(DG)is simulated using ETAP *** proposed protection algorithm is modeled and evaluated using MATLAB *** proposed fault detector and abnormality detector can enable quick and accurate fault identification and isolation.

关键词： Fault index coefficients Microgrid(MG) Micro-phasor measurement unit(μPMU) Renewable energy source(RES) Smart protection scheme(SPS)

Analysis and Characterization of Pore System and Grain Sizes of Carbonate Rocks from Southern Lebanon

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Journal of Earth Science 2023年第1期34卷 101-121页

作者： Mohamed K.salah Hammad Tariq Janjuhah Josep Sanjuan Department of Geology American University of BeirutRiad El SolhBeirut11072020Lebanon Department of Geology Shaheed Benazir Bhutto UniversitySheringal KP10850Pakistan Department of Earth and Ocean Dynamics Faculty of Earth SciencesUniversity of BarcelonaBarcelona08028Spain

Carbonate rocks are common in many parts of the world, including the Eastern Mediterranean, where they host significant groundwater supplies and are widely used as building and ornamental stones. The porosity of carbonate rocks plays a critical role in fluid storage and retrieval. The pore structure connectivity, in particular, controls many properties of geological formations, as well as the relationships between the properties of individual minerals and the bulk properties of the rock. To study the relationships between porosity, rock properties, pore structure, pore size, and their impact on reservoir characteristics, 46 carbonate rock samples were collected from four stratigraphic sections exposed near Sidon, South Lebanon. The studied carbonate rocks are related to marine deposits of different ages(e.g., Upper Cretaceous, Eocene, and Upper Miocene). In order to understand the pore connectivity, the MICP(mercury injection capillary pressure) technique was conducted on ten representative samples. Results from the SEM analysis indicate the dominance of very fine and fine pore sizes, with various categories ranging in diameter from 0.1 to10 μm. The MICP data revealed that the pore throat radii vary widely from 0.001 to 1.4 μm, and that all samples are dominated by micropore throats. The grain size analysis indicated that the studied rocks have significant amounts of silt-and clay-size grains with respect to the coarser ‘sand-size’ particles, suggesting a high proportion of microporosity. Obtained results, such as the poorly-sorted nature of grains, high microporosity, and the high percentage of micropore throats, justify the observed low mean hydraulic radius, the high entry pressure, and the very low permeability of the studied samples. These results suggest that the carbonate rocks near Sidon(south of Lebanon) are possibly classified as non-reservoir facies.

关键词： petrophysics mercury injection capillary pressure(MICP) micrite microtexture microporosity platform carbonates southern Lebanon