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Inertial sensors technologies for navigation applications:state of the art and future trends

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Satellite Navigation 2020年第1期1卷 9-29页

作者： Naser El-Sheimy ahmed youssef Mobile Multi-sensor Systems Research Team Department of Geomatics EngineeringUniversity of Calgary2500 University Drive N.WCalgaryAB T2N 1N4Canada

Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of *** opposed to other position fixing navigation techniques,inertial navigation performs the navigation in a relative sense with respect to the initial navigation state of the moving ***,inertial navigation systems are not prone to jamming,or *** navigation systems have developed vastly,from their occurrence in the 1940s up to *** accuracy of the inertial sensors has improved over time,making inertial sensors sufficient in terms of size,weight,cost,and accuracy for navigation and guidance *** the past few years,inertial sensors have developed from being purely mechanical into incorporating various technologies and taking advantage of numerous physical phenomena,from which the dynamic forces exerted on a moving body could be computed ***,the evolution of inertial navigation scheme involved the evolution from stable-platform inertial navigation system,which were mechanically complicated,to computationally demanding strap-down inertial navigation *** sensory technologies have provided highly accurate inertial sensors,at smaller ***,the vibratory inertial navigation technologies enabled the production of Micro-electro-machined inertial sensors that are extremely low-cost,and offer extremely low size,weight and power consumption,making them suitable for a wide range of day-to-day navigation ***,advanced inertial sensor technologies have been introduced to the industry such as nuclear magnetic resonance technology,coldatom technology,and the reintroduction of fluid-based inertial *** another note,inertial sensor errors constitute a huge research aspect in which it is intended for inertial sensors to reach level in which they could operate for substantially long operation times in the absence of updates from aiding sensors,which would be a hug

关键词： Gyroscopes Accelerometers Optical inertial sensors Micro-electro-machined Fluid-based inertial sensors Stochastic modeling

Landslide susceptibility mapping using machine learning algorithms and comparison of their performance at Abha Basin,Asir Region,Saudi Arabia

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Geoscience Frontiers 2021年第2期12卷 639-655页

作者： ahmed Mohamed youssef Hamid Reza Pourghasemi Geology Department Faculty of ScienceSohag UniversityEgypt Geological Hazards Department Applied Geology SectorSaudi Geological SurveyP.O.Box 54141Jeddah21514Saudi Arabia Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran

The current study aimed at evaluating the capabilities of seven advanced machine learning techniques(MLTs),including,Support Vector Machine(SVM),Random Forest(RF),Multivariate Adaptive Regression Spline(MARS),Artificial Neural Network(ANN),Quadratic Discriminant Analysis(QDA),Linear Discriminant Analysis(LDA),and Naive Bayes(NB),for landslide susceptibility modeling and comparison of their *** machine learning algorithms with spatial data types for landslide susceptibility mapping is a vitally important *** study was carried out using GIS and R open source software at Abha Basin,Asir Region,Saudi ***,a total of 243 landslide locations were identified at Abha Basin to prepare the landslide inventory map using different data *** the landslide areas were randomly separated into two groups with a ratio of 70%for training and 30%for validating *** landslide-variables were generated for landslide susceptibility modeling,which include altitude,lithology,distance to faults,normalized difference vegetation index(NDVI),landuse/landcover(LULC),distance to roads,slope angle,distance to streams,profile curvature,plan curvature,slope length(LS),and *** area under curve(AUC-ROC)approach has been applied to evaluate,validate,and compare the MLTs *** results indicated that AUC values for seven MLTs range from 89.0%for QDA to 95.1%for *** findings showed that the RF(AUC=95.1%)and LDA(AUC=941.7%)have produced the best performances in comparison to other *** outcome of this study and the landslide susceptibility maps would be useful for environmental protection.

关键词： Landslide susceptibility Machine learning algorithms Variables importance Saudi Arabia

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

Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using MAX phase Cr2TiAlC2 saturable absorber

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Optoelectronics Letters 2025年第1期21卷 7-12页

作者： ahmed Shakir AL-HITI Hiba HASSAN Department of Electrical Engineering Faculty of Engineering University of Anbar Department of Laser and Optoelectronics Engineering University of Technology-Iraq

We demonstrated a new type of MAX phase material, chromium titanium aluminum carbide（Cr2TiAlC2） polymer film, to generate a passively Q-switched erbium-doped fiber laser（EDFL）. The film thickness was measured to be around 45 μm, which was fabricated using the embedding method with polyvinyl alcohol（PVA） polymer as hoster. The saturable absorber（SA） film demonstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm and 1 560.19 nm, respectively. The Q-switching pulse duration could be varied from 2.46 μs to 770 ns, while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 mW. The maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW, respectively.

关键词： Saturable absorbers

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

Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions

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Neural Regeneration Research 2025年第1期20卷 191-192页

作者： Narek Manukjan Daniel Fulton Zubair ahmed WMatthijs Blankesteijn Sébastien Foulquier Department of Pharmacology and Toxicology Maastricht UniversityMaastrichtThe Netherlands CARIM-School for Cardiovascular Diseases Maastricht UniversityMaastrichtThe Netherlands Neuroscience and Ophthalmology Institute of Inflammation and AgeingUniversity of BirminghamEdgbastonBirminghamUK Centre for Trauma Sciences Research University of BirminghamEdgbastonBirminghamUK MHeNs-School for Mental Health and Neuroscience Maastricht UniversityMaastrichtThe Netherlands Department of Neurology Maastricht University Medical CenterMaastrichtThe Netherlands

As the population ages,the burden of age-related diseases becomes ***,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common ***,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(cSVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of *** term cSVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CSVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018).

关键词： pathology becoming white

RESPONSE OF MICROPOLAR THERMOELASTIC SOLID WITH VOIDS DUE TO VARIOUS SOURCES UNDER GREEN NAGHDI THEORY

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Acta Mechanica Solida Sinica 2012年第2期25卷 197-209页

作者： Mohamed Ibrahim ahmed Othman Sarhan youssef Atwa Department of Mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt Higher Institute of Engineer Dept.of Eng.Math.and PhysicsShorouk AcademyEgypt Faculty of Science Department of mathematicsShaqra UniversityAL-QuwaiyahSaudi Arabia

Green-Naghdi （G-N） theory of thermoelasticity is employed to study the deformation of micropolar thermoelastic solid with voids considering the influence of various sources acting on the plane surface. The normal mode analysis is used to obtain the analytical expressions of the displacement components, force stress, coupled stress, variation of volume fraction field and temperature distribution. The computed results are presented graphically when the volume source is applied. Comparisons of type II and type III with and without micropolarity effect are made with the results predicted in the context of （G-N） theory.

关键词： micropolar thermoelastic solid volume fraction coupled stress energy dissipation,voids

Effect of Aging on the Toughness of Austenitic and Duplex Stainless Steel Weldments

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Journal of Materials Science & Technology 2010年第9期26卷 810-816页

作者： Omyma Hassan Ibrahim Ibrahim soliman Ibrahim Tarek ahmed Fouad Khalifa Metallurgy Dept. Nuclear Research CentreAtomic Energy Authority(Egypt) Nuclear Safety Centre Atomic Energy Authority(Egypt) Shoubra Faculty of Engineering Benha University

In the present study,the effect of aging heat treatment at 650,750,and 850？C on the impact toughness of 316L austenitic stainless steel,2205 duplex stainless steel and their weldments has been *** process was conducted using the TIG（tungsten inert gas） welding *** impact testing,at room temperature,was employed to determine the effect of aging treatment on the impact properties of investigated *** treatment resulted in degradation in the impact toughness as demonstrated by the reduction in the impact fracture energy and deformation parameters（strain hardening capacity,fracture deffection,and crack initiation and propagation energy）.The degree of embrittlement was more noticeable in duplex stainless steel parent and weld-metal than in 316L stainless steel and became greater with the increase of aging *** degradation in impact toughness was discussed in relation to the observed precipitation of the intermetallic sigma phase in the microstructure of the stainless steel weldments and the corresponding fracture surface morphology.

关键词： Austenitic and duplex stainless steels Aging Instrumented impact Toughness

Modelling and control of a grid-connected AC microgrid with the integration of an electric vehicle

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Clean Energy 2023年第4期7卷 707-720页

作者： youssef Akarne ahmed Essadki Tamou Nasser Hammadi Laghridat Higher National School of Arts and Crafts(ENSAM) Mohammed V UniversityRabatMorocco National High School for Computer Science and Systems Analysis(ENSIAS) Mohammed V UniversityRabatMorocco

The purpose of this paper is to propose an efficient model and a robust control that ensures good power quality for the AC microgrid(MG)connected to the utility grid with the integration of an electric vehicle(EV).The MG consists of two renewable energy sources:a photovoltaic system(PVS)and a wind turbine system(WTS)based on a permanent magnet synchronous generator(PMSG),with the integration of an *** sources are used to supply active and reactive power to the AC bus and the utility *** power point tracking(MPPT)based on the perturb-and-observe(PO)method is used to increase the efficiency of the photovoltaic modules and improve overall *** MG system includes a 2-MW WTS,a 100-kW PVS and 12 kW provided by the *** validate the performance of the proposed system,a series of simulations were conducted using the MATLAB/Simulink?*** results demonstrate that the proposed system ensures high performance in terms of power quality,system stability,power tracking and safe integration of the EV.

关键词： microgrid wind turbine system photovoltaic system electric vehicle grid-to-vehicle vehicle-to-grid control systems