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Novel aspects for thermal stability studies and shelf life assessment of modified double-base propellants

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Defence Technology（防务技术） 2019年第3期15卷 300-305页

作者： Sherif Elbasuney Ashraf.M. A. Elghafour Mostafa radwan Ahmed Fahd Hosam Mostafa Ramy Sadek amr Motaz School of Chemical Engineering Military Technical College Kobry El-Kobba Cairo Egypt British University in Egypt Elshrouk city Cairo Egypt

Modified DB propellants, based on energetic nitramine(RDX) were manufactured by solventless extrusion process. Thermal stability and shelf life assessment of modified DB propellant were investigated. Shelf life assessment was evaluated using Van’t Hoff’s formula and artificial aging at 70℃ up to120 days. Quantification of total heat released and heat flow with aging time was conducted using differential scanning calorimetry(DSC) and thermal activity monitoring(TAMIII) respectively. Modified DB formulation based on 20 wt % RDX demonstrated enhanced thermal stability in terms of controlled heat flow, and slow decomposition reactions at elevated temperature. This formulation demonstrated extended service life up to 56 years compared with reference formulation. These novel finding was ascribed to the high thermal stability of RDX and its compatibility with DB constituents. This manuscript shaded the light on novel and effective approach for thermal stability via monitoring thermal activity with aging.

关键词： Double-base propellant Thermal stability Artificial aging Shelf-life assessment

Machine learning and data-driven prediction of pore pressure from geophysical logs:A case study for the Mangahewa gas field,New Zealand

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1799-1809页

作者： Ahmed E.radwan David A.Wood Ahmed A.radwan Faculty of Geography and Geology Institute of Geological SciencesJagiellonian UniversityKraków30-387Poland Exploration Department Gulf of Suez Petroleum CompanyCairoEgypt DWA Energy Limited LincolnUK Department of Geology Faculty of ScienceAl-Azhar UniversityAssiut BranchAssiut71524Egypt

Pore pressure is an essential parameter for establishing reservoir conditions,geological interpretation and drilling *** pressure prediction depends on information from various geophysical logs,seismic,and direct down-hole pressure ***,a level of uncertainty accompanies the prediction of pore pressure because insufficient information is usually recorded in many *** machine learning(ML)algorithms can decrease the level of uncertainty of pore pressure prediction uncertainty in cases where available information is *** this research,several ML techniques are applied to predict pore pressure through the over-pressured Eocene reservoir section penetrated by four wells in the Mangahewa gas field,New *** predictions substantially outperform,in terms of prediction performance,those generated using a multiple linear regression(MLR)*** geophysical logs used as input variables are sonic,temperature and density logs,and some direct pore pressure measurements were available at the reservoir level to calibrate the predictions.A total of 25,935 data records involving six well-log input variables were evaluated across the four *** ML methods achieved credible levels of pore pressure prediction *** most accurate models for predicting pore pressure in individual wells on a supervised basis are decision tree(DT),adaboost(ADA),random forest(RF)and transparent open box(TOB).The DT achieved root mean square error(RMSE)ranging from 0.25 psi to 14.71 psi for the four *** trained models were less accurate when deployed on a semi-supervised basis to predict pore pressure in the other *** two wells(Mangahewa-03 and Mangahewa-06),semi-supervised prediction achieved acceptable prediction performance of RMSE of 130—140 psi;while for the other wells,semi-supervised prediction performance was reduced to RMSE>300 *** results suggest that these models can be used to predict pore pressure in nearby locat

关键词： Machine learning(ML) Pore pressure Overburden Well-log derived predictions Overpressure

Reconstruction of earthquake hazard in regions of sparse seismic monitoring

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Earthquake Engineering and Engineering Vibration 2007年第2期6卷 99-109页

作者： amr S. Elnashai Mid-America Earthquake Center Department of Civil and Environmental Engineering University of Illinois Champaign at Urbana-Urbana IL USA

Studying strong motion records and the spatial distribution of ground shaking is of great importance in understanding the underlying causes of damage in earthquakes. Many regions in the world are either not instrumented or are sparsely instrumented. As such, significant opportunities for motion-damage correlations are lost. Two recent and damaging earthquakes belong to the class of lost opportunities, namely the Kashmir （Pakistan） earthquake of October 2005 and the Yogyakarta （Indonesia） earthquake of May 2006. In this paper, an overview of the importance of supply and demand studies in earthquake-stricken regions is given, followed by two examples of investigative engineering seismology aimed at reconstructing the hazard from sparse data. The paper closes with a plea for responsible authorities to invest in seismic monitoring networks in the very near future.

关键词： Kashmir earthquake Yogyakarta (Indonesia) earthquake field investigation hazard reconstruction sparse seismic monitoring back-analysis attenuation relationships

Herbal extracts counteract cisplatin-mediated cell death in rat testis

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Asian Journal of Andrology 2008年第2期10卷 291-297页

作者： amr Amin Alaaeldin A. Hamza amr Kambal Sayel Daoud Biology Department United Arab Emirates University AI-Ain 17551 United Arab Emirates Hematology Laboratory Twain Hospital At-Ain 15258 United Arab Emirates Histopathology Laboratory Twain Hospital At-Ain 15258 United Arab Emirates

Aim： To evaluate the protective effects of ginger （Gin） and roselle （Ros） against testicular damage and oxidative stress in a cisplatin （CIS）-induced rodent model. Their protective effects against CIS-induced apoptosis in testicular and epididymal sperms is also investigated. Methods： Ethanol extracts of Gin or Ros （1 g/***） were given orally to male albino rats for 26 days. This period began 21 days before a single CIS intraperitoneal injection （10 mg/kg body weight）. Results： Gin or Ros given orally significantly restored reproductive function. Both tested extracts notably reduced the CIS-induced reproductive toxicity, as evidenced by restoring the testis normal morphology. In Gin and Ros, the attenuation of CIS-induced damage was associated with less apoptotic cell death both in the testicular tissue and in the sperms. CIS-induced alterations of testicular lipid peroxidation were markedly improved by these plant extracts. Conclusion： The present results provide further insights into the mechanisms of protection against CIS-induced reproductive toxicity and confirm the essential anti-oxidant potential of both examined extracts. （Asian J Androl 2008 Mar; 10： 291-297）

关键词： cisplatin cell death toxicity flow cytometry ginger roselle

A Reliable and Scalable Internet of Military Things Architecture

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Computers, Materials & Continua 2021年第6期67卷 3887-3906页

作者： Omar Said amr Tolba Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Computer Science Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Department of Mathematics and Computer Science Faculty of ScienceMenoufia UniversityShebin Elkoum32511Egypt

Recently,Internet of Things(IoT)technology has provided logistics services to many disciplines such as agriculture,industry,and ***,it has become one of the most important scientific research *** IoT to military domain has many challenges such as fault tolerance and *** this paper,IoT technology is applied on the military field to create an Internet of Military Things(IoMT)***,the architecture of the aforementioned IoMT system is *** architecture consists of four main layers:Communication,information,application,and decision *** layers provided a fault tolerant coverage communication system for IoMT ***,it implemented data reduction methods such as filtering,compression,abstraction,and data prioritization queuing system to guarantee QoS for the transmitted ***,it used decision support technology and IoMT application unification ***,to evaluate the IoMT system,an intensive simulation environment is constructed using the network simulation package,*** simulation results proved that the proposed IoMT system outperformed the traditional military system with regard to the performance metrics,packet loss,end-to-end delay,throughput,energy consumption ratio,and data reduction rate.

关键词： Internet of things internet of military things simulation military battlefield

A peer-to-peer logic environment to validate flashing yellow arrow decision support system

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第5期8卷 735-750页

作者： Hatem Abou-Senna Essam radwan Hesham Eldeeb Center for Advanced Transportation Systems Simulations(CATSS) Department of CivilEnvironmental and Construction Engineering(CECE)University of Central FloridaOrlandoFL 32816USA Deep Numerics LLC.OrlandoFL 32820USA

The flashing yellow arrow(FYA)signal display creates an opportunity to enhance the leftturn phase with a variable mode that can be changed on *** research develops an integrated general purpose data collection module that time stamps detector and phase state changes within a National Electrical Manufacturers Association(NEMA)actuated traffic signal controller to provide recommendations for the flashing yellow arrow left-turn mode on a cycle-by-cycle basis.115 left-turn approaches at 38 intersections with locations across the State of Florida were analyzed totaling 1370 h of video data processed including off-peak and peak *** data extraction was an essential step in developing thegap thresholds for the permissive *** intersection field data were obtained through loop detector mapping to the controller in the lab in real-time mode using a peerto-peer logic environment.A custom communications software was developed to retrieve instantaneous channel input data,synchronize opposing through green phase,analyze traffic information,provide the algorithm decision,and generate a real-time log recording the events to determine whether it would be optimal to switch the red arrow to a flashing yellow *** algorithm determines the time interval between the successive arrivals of vehicles and computes the corresponding headway for each lane by cycle on a secondby-second ***-to-peer logic is a necessary step to verify and validate new traffic concepts prior to field-testing and offers the advantage of acquiring and analyzing realtime traffic data coupled with video feed with the benefit of a safe environment.

关键词： Traffic engineering Peer-to-peer logic Flashing yellow arrow Decision support system Permissive left-turn Four section head

State of the Art in Alcohol Sensing with 2D Materials

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Nano-Micro Letters 2020年第3期12卷 22-54页

作者： Ramin Boroujerdi amr Abdelkader Richard Paul Faculty of Science and Technology Bournemouth UniversityTalbot CampusFern BarrowPoole BH125BBUK Department of Engineering University of CambridgeCambridge CB30FSUK

Since the discovery of graphene,the star among new materials,there has been a surge of attention focused on the monatomic and monomolecular sheets which can be obtained by exfoliation of layered *** materials are known as two-dimensional(2D)materials and offer enormous versatility and *** ultimate single atom,or molecule,thickness of the 2D materials sheets provides the highest surface to weight ratio of all the nanomaterials,which opens the door to the design of more sensitive and reliable chemical *** variety of properties and the possibility of tuning the chemical and surface properties of the 2D materials increase their potential as selective sensors,targeting chemical species that were previously difficult to *** planar structure and the mechanical flexibility of the sheets allow new sensor designs and put 2D materials at the forefront of all the candidates for wearable *** developing sensors for alcohol,the response time is an essential factor for many industrial and forensic applications,particularly when it comes to hand-held ***,we review recent developments in the applications of 2D materials in sensing alcohols along with a study on parameters that affect the sensing *** review also discusses the strategies used to develop the sensor along with their mechanisms of sensing and provides a critique of the current limitations of 2D materials-based alcohol sensors and an outlook for the future research required to overcome the challenges.

关键词： Sensors and biosensors Alcohol probes Electrochemical detectors Ethanol metabolites 2D materials

SmartSurf^(ACE)transepithelial photorefractive keratectomy with mitomycin C enhancement after small incision lenticule extraction

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Eye and Vision 2021年第1期8卷 276-285页

作者： amr A.Gab‑Alla Faculty of Medicine Ophthalmology DepartmentSuez Canal UniversityRing RoadIsmailiaEgypt

Background:To evaluate predictability,stability,efficacy,and safety of transepithelial photorefractive keratectomy(TPRK)using smart pulse technology(SPT)(SmartSurface procedure)of Schwind Amaris with mitomycin C for correction of post small incision lenticule extraction(SMILE)myopic residual refractive ***:This study is a prospective,non-comparative case series conducted at a private eye centre in Ismailia,Egypt,on eyes with post-SMILE myopic residual refractive errors because of undercorrection or suction loss(suction loss occurred after the posterior lenticular cut and the creation of side-cuts;redocking was attempted,and the treatment was completed in the same session with the same parameters)with myopia or myopic *** patients were followed up post-SMILE for six months before the SmartSurface procedure,and then they were followed up for one year after *** were performed using Amaris excimer laser at 500 *** main outcomes included refractive predictability,stability,efficacy,safety and any reported ***:This study included 68 eyes of 40 patients out of 1920 total eyes(3.5%)with post-SMILE technique myopic residual refractive *** average duration between the SMILE surgery and TPRK was 6.7±0.4 months(range 6 to 8 months).The mean refractive spherical equivalent(SE)was within±0.50 D of plano correction in 100%of the eyes at 12 months *** of<0.50 D was achieved in 100%of the *** mean of the residual SE error showed statistically significant improvement from preoperative−1.42±0.52 D to 0.23±0.10 D(P<0.0001).Uncorrected distance visual acuity(UDVA)(measured by Snellen’s chart and averaged in logMAR units)was improved significantly to 0.1±0.07(P<0.0001).UDVA was 0.2 logMAR or better in 100%of the eyes,0.1 logMAR or better in 91.2%of the eyes,and 0.0 logMAR in 20.6%of the *** distance visual acuity(CDVA)remained unchanged in 79.4%of eyes.14.7%of eyes gained one line of CDVA(Snellen).

关键词： Transepithelial PRK Mitomycin C Refractive enhancement Small incision lenticule extraction Smart pulse technology SmartSurface procedure

A numerical investigation into the effect of altering compression ratio, injection timing, and injection duration on the performance of a diesel engine fuelled with diesel-biodiesel-butanol blend

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Clean Energy 2024年第5期8卷 73-96页

作者： Abdulkarim Youssef amr Ibrahim Mechanical Engineering Department Beirut Arab University115020 BeirutLebanon Mechanical Engineering Department Alexandria UniversityAlex 21544Egypt

Using renewable fuels for diesel engines can reduce both air pollution and dependence on fossil fuels.A computer simulation was constructed to predict the performance,combustion characteristics,and NOx emissions of a diesel engine fuelled with diesel-biodiesel-butanol *** simulation was validated by comparing the modelling results against experimental data and a good agreement between the results was *** fuels used for the validation were diesel(B0),biodiesel(B100),diesel-biodiesel blend(B50),and two diesel-biodiesel-butanol blends with 45%diesel-45%biodiesel-10%butanol(Bu10)and 40%diesel-40%biodiesel-20%butanol(Bu20)by *** results showed that the addition of butanol reduced NOx emissions but deteriorated the engine *** aim of the current work was the numerical optimization of the different parameters to enhance the engine performance while using butanol to decrease NOx *** engine compression ratio(CR)varied from 14 to 24,in increments of *** injection timing(IT)was reduced from 30°before top dead centre(bTDC)to 5°bTDC in increments of 5°.Also,the fuel injection duration(IDur)was extended from 20°to 50°in increments of 10°.Results showed that the increase in the CR improved engine performance for the two investigated fuels,Bu10 and *** maximum engine brake power(BP),thermal efficiency(BTE),and minimum brake-specific fuel consumption(BSFC)of 1.46 kW,32.3%,and 0.273 kg/kWh respectively,were obtained when the Bu10 fuel was injected under the optimum conditions of 24 CR,15°bTDC IT,and 40°*** these optimum conditions,the BP,BTE,and BSFC improved by 3%-3.5%for Bu10 and Bu20 fuel blends compared with the base engine conditions of a CR of 22,30°IDur,and 10°bTDC *** heat release rate during the premixed phase increased when the IT was advanced,while the mixing-controlled combustion phase was enhanced when the IT was *** emissions increased with increasing CR,while both an increase in IDur at con

关键词： compression ratio injection timing injection duration butanol biodiesel diesel