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Roll-pitch-yaw autopilot design for nonlinear time-varying missile using partial state observer based global fast terminal sliding mode control

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Chinese Journal of Aeronautics 2016年第5期29卷 1302-1312页

作者： ahmed awad Wang Haoping Sino-French International Joint Laboratory of Automatic Control and Signal Processing (LaFCAS) School of AutomationNanjing University of Science & Technology

The acceleration autopilot design for skid-to-turn （STT） missile faces a great challenge owing to coupling effect among planes, variation of missile velocity and its parameters, inexistence of a complete state vector, and nonlinear aerodynamics. Moreover, the autopilot should be designed for the entire flight envelope where fast variations exist. In this paper, a design of integrated roll-pitch-yaw autopilot based on global fast terminal sliding mode control （GFTSMC） with a partial state nonlinear observer （PSNLO） for STT nonlinear time-varying missile model, is employed to address these issues. GFTSMC with a novel sliding surface is proposed to nullify the integral error and the singularity problem without application of the sign function. The proposed autopilot consisting of two-loop structure, controls STT maneuver and stabilizes the rolling with a PSNLO in order to estimate the immeasurable states as an output while its inputs are missile measurable states and control signals. The missile model considers the velocity variation, gravity effect and parameters＇ variation. Furthermore, the environmental conditions＇ dynamics are mod- eled. PSNLO stability and the closed loop system stability are studied. Finally, numerical simulation is established to evaluate the proposed autopilot performance and to compare it with existing approaches in the literature.

关键词： Flight control system Global fast terminal slidingmode control Integrated autopilot Nonlinear state observer Skid-to-turn missile

Sequence architecture of a Jurassic ramp succession from Gebel Maghara(North Sinai,Egypt):Implications for eustasy

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Journal of Palaeogeography 2015年第3期4卷 305-330页

作者： ahmed awad Abdelhady Franz Theodor Fürsich Geology Department Faculty of ScienceMinia University FG Pal?oumwelt Geozentrum Nordbayern der Universit?t Erlangen

The Jurassic succession at Gebet Maghara, North Sinai, Egypt, represents a mixed carbonate-siticictastic sequence. Combining information from both fossits and rocks attowed a ptausibte reconstruction of the depositionat environments and of the basin evotution. The Ju- rassic succession of Gebel Maghara was deposited on a ramp, and the architecture of the ramp facies was strongty controtted not onty by sea-revel changes but atso by extensionat tectonics in connection with rifting of the Tethys, North Gondwana. Seven tectonicalty modified thirdorder sequences （DS 1-DS 7） have been recognized. The first three sequences （DS 1-DS 3）, ranging from the Toarcian to the Bajocian, record sea invasion （intertidat to shattow subtida[lconditions） across an intracratonic area as a resutt of eustatic sea-fever changes during a quiescent rift stage. The remaining sequences （DS 4-DS 7） reflect open marine mid to outer ramp settings. Non-marine conditions around the Bajocian-Bathonian boundary, documented by catiche, represent the maximum regression of the sea. During an active extensionat stage, horsts, which formerty acted as barriers separating the Maghara sub-basin from the main ocean, subsided. Subsequent rejuvenation and reactivation of fautts shifted the homoctinat physiography of the ramp to a distatty steepened ramp during the earty Bathonian, creating a 200-m-thick dettaic wedge. SimiLar processes during the earty Kimmeridgian created a catcirudite-catcarenite succession of stope origin. The diversity and the epifaunat/infaunat percentage of the macrofauna disptay a cyctic pattern which coincides more or tess with the sequence stratigraphic architecture.

关键词： facies sequence stratigraphy ramp extensional basin Jurassic Gebel Maghara Egypt

Expression levels ofβcatenin and galectin-3 in meningioma and their effect on brain invasion and recurrence:a tissue microarray study

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Cancer Biology & Medicine 2017年第3期14卷 319-326页

作者： Rehab allah ahmed Abdelhadi M Shebl Hany Onsy Habashy Department of Pathology Mansoura UniversityFaculty of MedicineMansoura DK 35516Egypt

Objective:Meningiomas are neoplasms that arise from the meninges of the central nervous system(CNS).They constitute about25.6%of CNS tumors diagnosed in *** morphological variants of meningiomas display aggressive behavior,leading to brain-invasive growth *** meningiomas are usually treated by complete surgical excision,the risk of postoperative recurrence ***,additional biomarkers for predicting aggressive behavior must be *** study aims to explore the clinical and biological relevance of the protein expression levels ofβ-catenin and galectine-3 in meningioma and to understand the pathobiology of this ***:This retrospective study was carried out on 153 cases of meningioma by using tissue microarrays and immunohistochemistry forβ-catenin and ***:Highβ-catenin expression was significantly associated with transitional and meningiotheliomatous meningiomas,low tumor grade,low recurrence rate,and low incidence of brain ***,high galectin-3 expression was associated with brain invasion,recurrence,high tumor grade,and tumor *** regression analysis indicated that among all variables included in the model,β-catenin and galactin-3 expression levels were significant predictors of tumor recurrence(P<0.001).Conclusions:Galectin-3 andβ-catenin are involved in meningioma recurrence but not in brain *** molecules could be important potential therapeutic targets and predictors for meningiomas.

关键词： Immunohistochemistry meningioma recurrence brain invasion galectin-3 and β-catenin

Impact Assessment and Mitigation Techniques for High Penetration Levels of Renewable Energy Sources in Distribution Networks:Voltage-control Perspective

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 450-458页

作者： ahmed S.A.awad Dave Turcotte Tarek H.M.El-Fouly Natural Resources Canada Can-metENERGYVarennesCanadaon leave from the Electrical Power and Machines DepartmentFaculty of EngineeringAin Shams UniversityCairo 11566Egyp Natural Resources Canada CanmetENERGYVarennesCanada Advanced Power and Energy Center Khalifa UniversityAbu DhabiUnited Arab Emirates

The integration of renewable distributed generation(RDG)into distribution networks is promising and increasing ***,high penetration levels of distributed generation(DG)are often limited as they may have an adverse effect on the operation of distribution *** of the operation challenges is the interaction between DG and voltage-control equipment,e.g.,an under-load tap changer(ULTC),which is basically designed to compensate for voltage changes caused by slow load *** integration of variable DGs leads to rapid voltage fluctuations,which can negatively affect the tap operation of *** paper investigates the impact of high penetration levels of RDG on the tap operation of ULTC in distribution networks through *** mitigation techniques that can alleviate this impact are also *** these techniques,constant power-factor mode is regarded as the best trade-off between the simplicity and effectiveness of minimizing the number of tap *** are performed on a Canadian benchmark rural distribution feeder using OpenDSS software.

关键词： Renewable energy distributed generation(DG) voltage regulator load tap changer distribution network.

Data Reliability and Sensors Lifetime in Bridge Health Monitoring using LoRaWAN-Zigbee

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Computers, Materials & Continua 2022年第11期73卷 2663-2678页

作者： awad Ali Reyazur Rashid Irshad ahmed Abdu Alattaab Aamir Fatahayab Department of Computer Science College of Science and Arts-SharourahNajran UniversityNajranKingdom of Saudi Arabia Department of Computer Science JJTUJhunjhunuRajasthanIndia

The Wireless Sensor Network(WSN)is regarded as the fastest expanding technological trend in recent years due its application in a variety of *** the monitoring region,several sensor nodes with various sensing capabilities are installed to gather appropriate data and communicate it to the *** proposed system of the heterogeneous WSN employing LoRaWAN-Zigbee based hybrid communication is explored in this research *** communicate in a network,two Long–Range Wide Area Network(LoRaWAN)sensor clusters and two Zigbee sensor clusters are employed,together with two Zigbee and LoRaWAN *** suggested Golden eagle shepherd optimization(GESO)method then forms Zigbee as well as LoRaWAN networking ***,depending on energy usage and data packet size,the fitness of each sensor node is assessed using the Dynamic Intelligent Reasoning Based Neural(DIRN)*** software is used to implement and execute this *** the Zigbee network’s transmission distance is 650 m and the LoRaWAN network’s transmission range is 3.5 km,the system can function with a packet loss rate of less than 0.04 *** study shows significant gains in the performance of the system when compared to traditional approaches based on digital findings obtained on software solutions.

关键词： Zigbee LoRaWAN wireless sensor network health monitoring routing protocol

Joint Optimal Power Source Sizing and Data Collection Trip Planning for Advanced Metering Infrastructure Enabled by Unmanned Aerial Vehicles

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1337-1348页

作者： Haiam Shahin Mostafa F.Shaaban Mahmoud H.Ismail Hebat-allah M.Mourad ahmed Khattab Department of Electronics and Communications Engineering Facultyof EngineeringCairo UniversityGiza 12613Egypt IEEE Department of Electrical Engineering American University of SharjahPOBox 26666SharjahThe United Arab Emirates

The use of unmanned aerial vehicles(UAVs) in the collection of data from wireless devices, sensor nodes, and the Internet of Things(IoT) devices has recently received significant attention. In this paper, we investigate the data collection process from a set of smart meters in advanced metering infrastructure(AMI) enabled by UAVs. The objective is to minimize the total annual cost of the electric utility by jointly optimizing the number of UAVs, their power source sizing, the charging locations as well as the data collection trip planning. This is achieved while considering the energy budgets of batteries of UAVs and the required amount of collected data. The problem is formulated as a mixed-integer nonlinear programming(MINLP), which is decoupled into two sub-problems where a candidate UAV and a number of buildings are first grouped into trips via genetic algorithms(GAs), and then the optimum trip path is found using a traveling salesman problem(TSP) branch and bound algorithm. Simulation results show that the battery capacity or the number of UAVs increases as the coverage area or the density increases.

关键词： Advanced metering infrastructure unmanned aerial vehicle power source sizing trip planning genetic algorithm

The Research And Development of Sunlite Yarn Fabric Used as Thermal Underwear And The Study of Its Wear Performance

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The Research And Development of Sunlite Yarn Fabric Used as ...

作者： ahmed awad ABDELMALIK ABDELTAM 东华大学

学位级别：硕士

There is an amount of fibers used for thermal fabrics in textile market nowadays, such as wool, kapok and some types of synthetic fibers. A polydihydricals alcohol terephthalate, its trademark is Sunlite, was introduced into the market. It has a hollow space in the center of the fiber. In this paper, it was studied to see if its properties meet the criteria of warm underwear. Two types of yarn number SunLite yarn are used to produce plain stitch fabric with single jersey-knitting machine. Then the fabrics are treated with scoring, dyeing and softening. The fabrics are undergone with an optimal softening plan according to orthogonal design. HDP softener with concentration of 3% shows the best result. After that the properties of the produced fabrics are tested of all the performance required for thermal underwear, including pilling, Thermal resistance, Humidity resistance, Appearance and appearance retention, vertical wicking, Wash and color Fastness, Abrasion Fastness, fiber surface morphology by SEM and Permeability. Then the relevant wear performance of Sunlite fabrics is compared with kapok/cotton blended yarn fabrics. The results showed that. Sunlite fabrics have superior properties of anti-pilling, dimensional stability, wash and abrasion fastness than that of Kapok-cotton blended yarn fabric. While on thermal resistance and humidity resistance, vertical wicking, Sunlite fabrics showed inferior performance than that of kapok/cotton blended yarn fabric.

关键词： SunLite fiber knitted fabric orthogonal design wear performance warm underwear

Salinity Stress Alleviation by Foliar Bio-Stimulant, Proline and Potassium Nutrition Promotes Growth and Yield Quality of Garlic Plant

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Open Journal of Soil Science 2020年第9期10卷 443-458页

作者： Eman F. A. awad-allah Mona G. Attia ahmed M. Mahdy Soil and Water Sciences Department Faculty of Agriculture Alexandria University Alexandria Egypt Ministry of Agriculture Salinity and Alkalinity Soil Research Laboratory Cairo Egypt

Soil salinity is one of the major yield-limiting factors for crop production in many agricultural regions all over the world. Besides following efficient management practices at the field scale to reduce accumulation of salts in the effective root-zone, the effective use of treatments to alleviate the effects of salinity stress and improve crop salt tolerance is a promising solution to ensure crop production in such adverse conditions. A field experiment was carried out to investigate the effect of foliar spray with plant-based biostimulant (i.e. with and/or without 3% yeast extract), three levels of proline (0, 25, and 50 mM), and combined with potassium fertilizers, as potassium sulfate, 48% K2O (0, 50, and 100 kg/fed.) on growth promotion, chemical composition of garlic leaves, bulb quality parameters as well as yield and its components of garlic plant grown under moderate saline soil. Results revealed that the interaction between foliar spray with yeast extract at 3% and proline at 50 mM combined with proper K level at 100 kg/fed., was the best interaction treatment for increasing vegetative growth parameters, i.e. plant height, number of leaves per plant, and mineral contents (N, P, K, S, Ca and Mg in leaves), and proline content of garlic leaves after 135 days from planting time, total yield/fed., and garlic yield quality parameters at harvesting time. In conclusion, the detrimental effects of salinity stress can be alleviated by stress tolerance-inducing compounds, such as yeast extract and proline with proper application rate of K fertilization during the growing season of garlic crop.

关键词： Proline Potassium Yeast Extract Garlic Plant Salinity Stress Soil Reclamation

A Comprehensive Review on Charging Topologies and Power Electronic Converter Solutions for Electric Vehicles

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 675-694页

作者： Abdelfatah Ali Hossam H.H.Mousa Mostafa F.Shaaban Maher A.Azzouz ahmed S.A.awad the Department of Electrical Engineering American University of Sharjah26666 SharjahUnited Arab Emirates the Department of Electrical Engineering South Valley University83523 QenaEgypt the Department of Electrical and Computer Engineering University of WindsorWindsorON N9B 3P4 Canada Electrical Engineering Department Qatar UniversityDoha 2713Qatar Department of Electrical and Computer Engineering Sultan Qaboos UniversityMuscat123Oman

Electric vehicles(EVs)are becoming more popular worldwide due to environmental concerns,fuel security,and price *** performance of EVs relies on the energy stored in their batteries,which can be charged using either AC(slow)or DC(fast)***,EVs can also be used as mobile power storage devices using vehicle-to-grid(V2G)*** electronic converters(PECs)have a constructive role in EV applications,both in charging EVs and in ***,this paper comprehensively investigates the state of the art of EV charging topologies and PEC solutions for EV *** examines PECs from the point of view of their classifications,configurations,control approaches,and future research prospects and their impacts on power *** can be classified into various topologies:DC-DC converters,AC-DC converters,DC-AC converters,and AC-AC *** address the limitations of traditional DC-DC converters such as switching losses,size,and high-electromagnetic interference(EMI),resonant converters and multiport converters are being used in high-voltage EV ***,power-train converters have been modified for high-efficiency and reliability in EV *** paper offers an overview of charging topologies,PECs,challenges with solutions,and future trends in the field of the EV charging station applications.

关键词： Charging station charging topology electric vehicle power electronic converter vehicle-to-grid