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A new Approach to Estimate True Position of Unmanned Aerial Vehicles in an InS/GPS Integration System in GPS Spoofing Attack Conditions

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International Journal of Automation and computing 2018年第6期15卷 747-760页

作者： Mohammad Majidi Alireza Erfanian hamid Khaloozadeh Department of Electrical Engineering Malek-Ashtar University of Technology Tehran 15875-1774 Iran Faculty of Electrical Engineering Malek-Ashtar University of Technology Tehran 15875-1774 Iran Faculty of Electrical Engineering K.N.Toosi University of Technology Tehran 16315-1355 Iran

This paper presents a new approach to estimate the true position of an unmanned aerial vehicle （UAV） in the conditions of spoofing attacks on global positioning system （GPS） receivers. This approach consists of two phases, the spoofing detection phase which is accomplished by hypothesis test and the trajectory estimation phase which is carried out by applying the adapted particle filters to the integrated inertial navigation system （InS） and GPS. Due to nonlinearity and unfavorable impacts of spoofing signals on GPS receivers, deviation in position calculation is modeled as a cumulative uniform error. This paper also presents a procedure of applying adapted particle swarm optimization filter （PSOF） to the InS/GPS integration system as an estimator to compensate spoofing attacks. Due to memory based nature of PSOF and benefits of each particle＇s experiences, application of PSOF algorithm in the InS/GPS integ- ration system leads to more precise positioning compared with general particle filter （PF） and adaptive unscented particle filer （AUPF） in the GPS spoofing attack scenarios. Simulation results show that the adapted PSOF algorithm is more reliable and accurate in estim- ating the true position of UAV in the condition of spoofing attacks. The validation of the proposed method is done by root mean square error （RMSE） test.

关键词： Inertial navigation system (InS)/global positioning system (GPS) integration unmanned aerial vehicles (UAVs) position estimation spoofing particle based filters

Prevalence and risk factors of asymptomatic hepatitis C virus infection in Egyptian children

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World Journal of Gastroenterology 2007年第12期13卷 1828-1832页

作者： MS El-Raziky M El-Hawary G Esmat AM Abouzied n El-Koofy n Mohsen S Mansour A Shaheen M abdel hamid H El-Karaksy Departments of Pediatrics Cairo University Cairo Egypt Departments of Tropical Medicine Cairo University Cairo Egypt Tropical Medicine Research Institute Cairo Egypt

AIM: To identify the prevalence, risk factors and manifestations of asymptomatic hepatitis C virus (HCV) infection in Egyptian children. METHODS: Children at the age of 1-9 years were screened for HCV antibodies and alanine aminotransferase (ALT) levels. Every child with elevated ALT and/or detectable HCV antibodies was tested for HCV RnA by RT-PCR and compared with two negative controls for risk factors and signs and symptoms of liver ***: We screened 1042 children, six of them had elevated ALT, negative HCV antibody and positive RnA, likely representing acute hepatitis C cases. Fifteen children were HCV seropositive, 5 of them were HCV RnA positive. Asymptomatic HCV infection was present in 2.02% (positive results for either HCV antibodies or HCV-RnA or both). Symptoms such as diarrhea, abdominal pain, history of fatigue and school absence because of illness and risk factors such as dental care were significantly more common among HCV positive cases than among controls. none of the HCV positive children was diagnosed as having signs of advanced liver disease upon clinical or ultrasonographic examination. COnCLUSIOn: Asymptomatic HCV infection is detectable in 2.02% Egyptian children.

关键词： Hepatitis C virus Child Egypt Prevalence Transfusion Risk factor

Thermal Analysis of a Phase Change Material Based Heat Sink for Cooling Protruding Electronic Chips

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Journal of Thermal Science 2009年第3期18卷 268-275页

作者： Mustapha FARAJI hamid EL QARnIA EI Khadir LAKHAL Fluids Mechanic and Energetic Laboratory Automatic Environment and Transfer Process Laboratory Cadi Ayyad University Faculty of Sciences Semlalia Department of Physics

This work aims to numerically study the melting natural convection in a rectangular enclosure heated by three discreet protruding electronic chips. The beat sources generate heat at a constant and uniform volumetric rate. A part of the power generated in the heat sources is dissipated to a phase change material （PCM, n-eicosane with melting temperature, Tm = 36℃）. numerical investigations were carded out in order to examine the effects of the plate thickness on the maximum temperature of electronic components, the percentage contribution of plate heat conduction on the total removed heat and temperature profiles in the plate. Con＇elations for the dimensionless secured working time （time to reach the threshold temperature, Tcr = 75℃） and the corresponding liquid fraction were derived.

关键词： Phase change material protruding electronic component natural convection

Ecological distribution of harmful epiphytic Oscillatoriales in Alexandria coast,Egypt,with special reference to DnA identification

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Journal of Coastal Life Medicine 2014年第4期 274-280页

作者： Amany abdel hamid Ismael Eman.abdel Razak Mohamed Mostafa Mohamed El-Sheikh Wafaa Hassan Hegazy Oceanography Department Faculty of ScienceAlexandria UniversityAlexandria 21511Egypt Botany Department Faculty of ScienceDamanhuor UniversityEgypt Botany Department Faculty of ScienceTanta UniversityTantaEgypt

Objective:To identify the potentially harmful epiphytic Oscillatoriales species and follow up their distribution along Alexandria ***:Samples were collected bimonthly from April 2009 to February 2010 at three sites along Alexandria *** morphological and molecular analyses were used for identifying the dominant ***:Five species belonging to two families were identified;Oscillatoria acutissima,Oscillatoria nigroviridis,Oscillatoria sp.,Lyngbya majuscule and Phormidium *** cell density ranged from 10^(3)to 126×10^(3)filament g^(-1)fresh weight *** morphological study of the dominant species,Oscillatoria sp.(Oscillatoria sp.W1)showed much similarity with Planktothrix agardhii with no heterocysts and akinetes,while molecular ananlysis(16S rDnA)clustered the species in the same group with Anabaena ***:The 16S rDnA genes are not suitable for identifying Oscillatoriales during the present study and another molecular method should be used instead.

关键词： Harmful algae DnA analysis epiphytes Oscillatoriales Alexandria Egypt

Synthesis and Mollucicidal Activity of Some new Bicyclic and Polycyclic Pyrimidine Derivatives

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Journal of Chemistry and Chemical Engineering 2010年第5期4卷 41-53页

作者： Mohamed abdel-Megid Mohamed abdel-hamid Awas Magdy Seada Kamelia Mohamed Elmhdy Mortta Mohamed Elsayed Chemistry Department Faculty of Education Ain Shams University Roxy Cairo I1711 Egypt Environmental Research Laboratory Theodor Bilharzias Research Institute Giza 10115 Egypt

Hydrazinolysis ofethylthiopyrimidine derivative 2 gave 2-hydrazinopyrimidine 3 which used as a convenient precursor for the synthesis of pyrazolylpyrimidines, hydrazones and pyrimidotriazines. Also, treatment of 2 with ethyl chloroacetate yielded n^-carbethoxymethyl-2-ethylthio-pyrimidine 15, which on reaction with ethyl carbazate and hydrazine hydrate afforded pyrimidotriazine and imidazopyrimidine, respectively. Chlorination of 2 using phosphorous oxycbloride yielded 4-chloropyrimidine 18, which reacted with some heterocyclic compounds having vicinal amino cyano groups to give some new polynuclear heterocyclic system. Also, the effect of some active methylene compounds on 18 was also studied. Some of the newly synthesized compounds were tested as mollucicidal agents against Biomphlaria alexandrina snails that caused intestinal bilharzias, the national problem in Egypt.

关键词： Pyrazolylpyrimidines pyrimidotriazines imidazopyrimidines pyrimidopyrimidines mollucicidal activity.

Energy level engineering of charge selective contact and halide perovskite by modulating band offset:Mechanistic insights

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Journal of Energy Chemistry 2021年第3期30卷 822-829页

作者： Yassine Raoui hamid Ez-Zahraouy Samrana Kazim Shahzada Ahmad BCMaterials Basque Center for MaterialsApplications and NanostructuresBld.Martina CasianoUPV/EHU Science ParkBarrio Sarriena s/n48940 LeioaSpain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain Laboratory of Condensed Matter and Interdisciplinary Sciences Faculty of SciencesMohammed V UniversityRabatMorocco

Mixed cation and anion based perovskites solar cells exhibited enhanced stability under outdoor conditions,however,it yielded limited power conversion efficiency when TiO_(2) and Spiro-OMeTAD were employed as electron and hole transport layer(ETL/HTL)*** inevitable interfacial recombination of charge carriers at ETL/perovskite and perovskite/HTL interface diminished the efficiency in planar(n-i-p)perovskite solar *** employing computational approach for uni-dimensional device simulator,the effect of band offset on charge recombination at both interfaces was *** noted that it acquired cliff structure when the conduction band minimum of the ETL was lower than that of the perovskite,and thus maximized interfacial ***,if the conduction band minimum of ETL is higher than perovskite,a spike structure is formed,which improve the performance of solar *** optimum value of conduction band offset allows to reach performance of 25.21%,with an open circuit voltage(VOC)of 1231 mV,a current density JSC of 24.57 mA/cm^(2) and a fill factor of 83.28%.Additionally,we found that beyond the optimum offset value,large spike structure could decrease the *** an optimized energy level of Spiro-OMeTAD and the thickness of mixed-perovskite layer performance of 26.56% can be *** results demonstrate a detailed understanding about the energy level tuning between the charge selective layers and perovskite and how the improvement in PV performance can be achieved by adjusting the energy level offset.

关键词： Device modelling Electron affinity Conduction band offset Valence band offset Charge recombination Perovskite solar cell

The Effect of Surface Pit Treatment on Fretting Fatigue Crack Initiation

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Computers, Materials & Continua 2021年第1期66卷 659-673页

作者： Qingming Deng Xiaochun Yin Magd abdel Wahab Department of Mechanics and Engineering Science Nanjing University of Science and TechnologyNanjing210094China Soete Laboratory Department of Electrical EnergyMetalsMechanical Constructions and SystemsFaculty of Engineering and ArchitectureGhent UniversityZwijnaarde9052Belgium Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam

This paper analyses the effect of surface treatment on fretting fatigue specimen by numerical simulations using Finite Element *** processed specimen refers to artificially adding a cylindrical pit to its contact ***,the contact radius between the pad and the specimen is controlled by adjusting the radius of the *** stress distribution and slip amplitude of the contact surface under different contact geometries are *** critical plane approach is used to predict the crack initiation life and to evaluate the effect of processed specimen on its fretting fatigue *** crack initiation life and angle can be predicted by the critical plane *** parameter is used to consider the effect of contact *** is shown that the crack initial position is dependent on the tensile *** same type of model,three kinds of critical plane parameters and Ruiz method provide very similar position of crack ***,the improved sample is much safer than the flat-specimen.

关键词： Finite element analysis surface pit stress distribution fretting fatigue critical plane approach

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华盛顿免疫学和过敏反应性疾病咨询手册

Effects of wollastonite nanofibers on fluid flow in medium-density fiberboard

丛书名：华盛顿医学咨询系列丛书

2005年

作者： Barbars Capes Jost Khaled M.abdel-hamid

本书介绍了过敏病人的诊疗方法、过敏性鼻炎和鼻窦炎、哮喘、过敏性眼病、昆虫过敏症、肥大细胞增多症、原发性免疫缺陷病等。

ISBN: (纸本)7543318350

本书介绍了过敏病人的诊疗方法、过敏性鼻炎和鼻窦炎、哮喘、过敏性眼病、昆虫过敏症、肥大细胞增多症、原发性免疫缺陷病等。

关键词：免疫性疾病变态反应病

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Journal of Forestry Research 2016年第1期27卷 209-217页

作者： hamid R.Taghiyari Younes Sarvari Samadi Wood Science and Technology Department Faculty of Civil Engineering Shahid Rajaee Teacher Training University Faculty of Wood Technology and Construction Rosenheim University of Applied Sciences

We studied the effect of wollastonite nanofibers on fluid flow in medium-density fiberboard （MDF）. nanowollastonite （nW） was applied in MDF at 10 %, based on the dry weight of wood fibers. We also tested chicken feathers as an additive to the matrix at 5 and 10 % by weight. The weight of feathers was reduced from the wood fibers to keep the density of the panels constant （0.66 g cm-3）. Wollastonite nanofibers acted as filler in the matrix and significantly decreased gas and liquid perme- ability. Higher thermal conductivity of the n-W-treated MDF-mats resulted in a better cure of resin, and conse- quently more integrity in the composite-matrix and lower permeability. The water-repellant property of wollastonite also contributed to the decrease in liquid permeability. Feathers reduced gas and liquid permeability due to the hydrophobic nature of keratin, as well as its formation as a physical barrier towards passing of fluids. Ten percent feather content proved too high and some checks and cracks occurred in the core of the panels after hot-pressing. Panels with 5 %-feather content resulted in both lower fluid flow and adequate physical integrity in the core sec- tion of the MDF-matrix.

关键词： Chicken feather Composite board Mineralmaterials Thermal conductivity coefficient Wollastonitenanofibers Wood fiber