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Hydrogen Detection With FBG Sensor Technology for Disaster Prevention

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Photonic Sensors 2013年第3期3卷 214-223页

作者： Said saad Lotfi HASSINE Group of Electronics and Quantum Physics Laboratory of Advanced Materials and Quantum Phenomena Faculty of Sciences of Tunis 2092 Tunisia National Institute of Applied Sciences and Technology University of Carthage North Urban Center of Tunis-B.P.676 Cedex Tunis-1080 Tunisia

Three fiber Bragg grating （FBG） sensors systems for hydrogen detection are presented using the classic Pd （palladium） coating technique （500nm） as the hydrogen sensitive film and titanium （Ti） as the adhesive layer with the etched cladding. These systems are compared and used for disaster environment prevention in hydrogen leakage environment where higher values than the normal are presented which increase the risk of explosion. With these systems, 0. 1% - 4% of the hydrogen volume concentration range in the volume ratio was detected and monitored experimentally in the test room with the very sensitive and stable value which reached 60pm/1% HE. In addition, a fast response time, about 6 s, was obtained with an advanced sensor.

关键词： Fiber Bragg gratin (FBG) hydrogen detection sensor disaster environment prevention Pd coating technique

Classified VPN Network Traffic Flow Using Time Related to Artificial Neural Network

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Computers, Materials & Continua 2024年第7期80卷 819-841页

作者： saad Abdalla Agaili Mohamed Sefer Kurnaz Department of Electrical and Computer Engineering Altinbas UniversityIstanbul34000Turkey

VPNs are vital for safeguarding communication routes in the continually changing cybersecurity ***,increasing network attack complexity and variety require increasingly advanced algorithms to recognize and categorizeVPNnetwork *** present a novelVPNnetwork traffic flowclassificationmethod utilizing Artificial Neural Networks(ANN).This paper aims to provide a reliable system that can identify a virtual private network(VPN)traffic fromintrusion attempts,data exfiltration,and denial-of-service *** compile a broad dataset of labeled VPN traffic flows from various apps and usage ***,we create an ANN architecture that can handle encrypted communication and distinguish benign from dangerous *** effectively process and categorize encrypted packets,the neural network model has input,hidden,and output *** use advanced feature extraction approaches to improve the ANN’s classification accuracy by leveraging network traffic’s statistical and behavioral *** also use cutting-edge optimizationmethods to optimize network characteristics and *** suggested ANN-based categorization method is extensively tested and *** show the model effectively classifies VPN traffic *** also show that our ANN-based technique outperforms other approaches in precision,recall,and F1-score with 98.79%*** study improves VPN security and protects against new *** VPNtraffic flows effectively helps enterprises protect sensitive data,maintain network integrity,and respond quickly to security *** study advances network security and lays the groundwork for ANN-based cybersecurity solutions.

关键词： VPN network traffic flow ANN classification intrusion detection data exfiltration encrypted traffic feature extraction network security

Oilfield produced water treatment in internal-loop airlift reactor using electrocoagulation/flotation technique

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Chinese Journal of Chemical Engineering 2018年第4期26卷 879-885页

作者： saad H.Ammar Ahmed S.Akbar Department of Chemical engineering AL-Nahrain University

Oilfield produced water is large quantities of salty water trapped in underground formations and subsisted under high temperatures and pressures that are brought to the surface along with oil during production. Produced water(PW) contains a lot of pollutants such as hydrocarbons and metals, this water must be treated before disposal. Therefore, different techniques are being used to treat produced water. Electrocoagulation is an efficient treatment technique involving the dissolution of anodes and formation of electro-coagulants, while the simultaneous generation of H_2 bubbles at the cathode leads to the pollutant removal by flotation. Electrocoagulation(EC)method is one of the most promising and widely used processes to treat oilfield produced water. In the present work, a conventional internal-loop(draught tube) airlift reactor was utilized as electrocoagulation/flotation cell for PW treatment by inserting two aluminum electrodes in the riser section of the airlift reactor. The EC airlift reactor was operated in a batch mode for the liquid phase. Different experimental parameters were studied on the oil and turbidity removal efficiencies such as current density, initial pH, electrocoagulation time, and air *** experimental results showed that mixing of the oil droplets in the PW was accomplished using only the liquid recirculation resulted by H_2 microbubbles generated by EC process which enhanced the oil removal. The experimental results further showed that the EC time required achieving ≥ 90% oil removal efficiency decreases from 46 to 15 min when operating current density increases from 6.8 to 45.5 mA·cm^(-2). This reactor type was found to be highly efficient and less energy consuming compared to conventional existing electrochemical cells which used mechanical agitation.

关键词： Produced water Wastewater treatment Electrocoagulation/flotation Internal loop Airlift reactor

Geotectonic significance of the Neoproterozoic ophiolitic metagabbros of Muiswirab area,South Eastern Desert,Egypt:constraints from their mineralogical and geochemical characteristics

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Acta Geochimica 2020年第6期39卷 887-910页

作者： Moustafa M.Mogahed Wlaa Mahmoud saad Geology Department Faculty of ScienceBenha University-EgyptP.O.Box 13518BenhaEgypt

Petrological and geochemical studies of Neo-proterozoic metagabbros were carried out in the Muiswirab area,South Eastern Desert of *** Muiswirab area comprises of ophiolitic metagabbroic rocks(MOM),which are tectonically thrusted over a thick pile of metavolcanic rocks and intruded by syn-and post-tectonic granitoid *** whole-rock geochemical variations coupled with chemical compositions of mineral constituents are used to attain the genesis and tectonic evolution of the studied *** geothermobarometric investiga-tion of the analyzed amphiboles from(MOM)revealed that these metagabbros underwent regional metamorphism under lower to upper greenschist facies(biotite zone)conditions(at a temperature of 450 to 500℃and pressure of 1-3 kbar).Geochemically,the metagabbros(MOM)show tholeiitic affinity and cxhibiting both arc-and MORB-like characters as evidenced by their clinopyrox-ene compositions and the Ti/V ratios(11.84-31.65),which considered as prominent features of forearc tectonic *** geochemical features suggest a probable fractionation of olivine±clinopyroxene±plagioclase as well as insignificant crustal *** parental magma of the investigated MOM rocks seems to be developed in a sub-arc mantle wedge setting due to the enrichments of LILE(e.g..Rb,Ba,Sr,Pb)over HFSE(e.g,Ti,Nb,Y,Zr,Hf,Ta).The studied MOM rocks have lower values of Nb/U relative to MORB and OIB indicating that their geochemical variation produced due to the enrichment of a lithosphere mantle by OIB like *** ratios of Zn/Fet,La/Sm,Sm/Yb,Th/Yb and Nb/Yb indicate that the MOM rocks represent a fragment of oceanic crust originated at a supra-subduction zone environment and their parental magma developed by 5-30%partial melting of a spinel lherzolite mantle rather than pyroxenite in an island arc setting and conformable with most of the Egyptian ophiolitic metagabbros.

关键词： Egypt Eastern Desert Muiswirab area Ophiolitic metagabbros N-MORB Arc tholeiites Foreare tectonic regime Volcanic-arc setting

An Adaptive Full Order Sliding Mode Controller for Mismatched Uncertain Systems

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International Journal of Automation and computing 2017年第2期14卷 191-201页

作者： Sanjoy Mondal Jawhar Ghommam Maarouf saad Department of Electrical Engineering Ecole de technologie superieure Montreal Canada-H3C1K3 Canada

In this paper, an adaptive full order sliding mode （FOSM） controller is proposed for strict feedback nonlinear systems with mismatched uncertainties. The design objective of the controller is to track a specified trajectory in presence of significant mismatched uncertainties. In the first step the dynamic model for the first state is considered by the desired tracking signal. After the first step the desired dynamic model for each state is defined by the previous one. An adaptive tuning law is developed for the FOSM controller to deal with the bounded system uncertainty. The major advantages offered by this adaptive FOSM controller are that advanced knowledge about the upper bound of the system uncertainties is not a necessary requirement and the proposed method is an effective solution for the chattering elimination from the control signal. The controller is designed considering the full-order sliding surface. System robustness and the stability of the controller are proved by using the Lyapunov technique. A systematic adaptive step by step design method using the full order sliding surface for mismatched nonlinear systems is presented, Simulation results validate the effectiveness of the proposed control law.

关键词： Full order sliding mode adaptive sliding mode finite time convergence reference tracking mismatched uncertainty.

Nanoarchitectured LiMn_2O_4/Graphene/ZnO Composites as Electrodes for Lithium Ion Batteries

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Journal of Materials Science & Technology 2014年第5期30卷 427-433页

作者： saad Aziz Jianqing Zhao Carrington Cain Ying Wang Department of Mechanical & Industrial Engineering Louisiana State University

LiMn2O4 nanoparticles are facilely synthesized using a sol-gel processing method. Graphene is added to LiMn2O4 electrode aiming at increasing specific capacity and improving rate capability. In order to further improve cycling stability of LiMn2O4/graphene electrode, atomic layer deposition （ALD） is used to deposit ultrathin ZnO coating composed of six ZnO ALD layers and modify the surface of either LiMn2O4/graphene electrode or individual LiMn2O4 particles to form nanoarchitectured LiMn2O4/graphene/ZnO electrodes. Both ZnO-ALD-modified LiMn2O4/graphene electrodes demonstrate enhanced cycling performance at 1C, retaining the final discharge capacity above 122 mA h g 1 after 100 electrochemical cycles, which is higher than 115 mA h g-1 of pristine LiMn2O4/graphene electrode and 109 mA h g-1 of bare LiMn2O4 electrode. The improved electrochemical performance of nanoarchitectured LiMn2O4/graphene/ZnO electrodes can be attributed to the cooperative effects from high electronic conductivity of graphene sheets to facilitate electron transportation and effective protection of ZnO ALD coating to restrict Mn dissolution and electrolyte decomposition.

关键词： LiMn2O4/graphene nanocomposite Atomic layer deposition Cathode material Lithium ion battery

An Enhanced Lung Cancer Detection Approach Using Dual-Model Deep Learning Technique

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 835-867页

作者： Sumaia Mohamed Elhassan saad Mohamed Darwish Saleh Mesbah Elkaffas Department of Information Technology Institute of Graduate Studies and ResearchAlexandria UniversityAlexandria21526Egypt College of Computing and Information Technology Arab Academy for ScienceTechnology and Maritime TransportAlexandriaP.O.Box 1029Egypt

Lung cancer continues to be a leading cause of cancer-related deaths worldwide,emphasizing the critical need for improved diagnostic *** detection of lung tumors significantly increases the chances of successful treatment and ***,current diagnostic methods often fail to detect tumors at an early stage or to accurately pinpoint their location within the lung ***-model deep learning technologies for lung cancer detection,while beneficial,cannot capture the full range of features present in medical imaging data,leading to incomplete or inaccurate ***,it may not be robust enough to handle the wide variability in medical images due to different imaging conditions,patient anatomy,and tumor *** overcome these disadvantages,dual-model or multi-model approaches can be *** research focuses on enhancing the detection of lung cancer by utilizing a combination of two learning models:a Convolutional Neural Network(CNN)for categorization and the You Only Look Once(YOLOv8)architecture for real-time identification and pinpointing of *** automatically learn to extract hierarchical features from raw image data,capturing patterns such as edges,textures,and complex structures that are crucial for identifying lung ***8 incorporates multiscale feature extraction,enabling the detection of tumors of varying sizes and scales within a single *** is particularly beneficial for identifying small or irregularly shaped tumors that may be challenging to ***,through the utilization of cutting-edge data augmentation methods,such as Deep Convolutional Generative Adversarial Networks(DCGAN),the suggested approach can handle the issue of limited data and boost the models’ability to learn from diverse and comprehensive *** combined method not only improved accuracy and localization but also ensured efficient real-time processing,which is crucial for practical clinical applicati

关键词： Lung cancer detection dual-model deep learning technique data augmentation CNN YOLOv8

A Methodology to Reduce Thermal Gradients Due to the Exothermic Reactions in Resin Transfer Molding Applications

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Fluid Dynamics & Materials Processing 2023年第1期19卷 95-103页

作者： Aouatif saad Mohammed EL Ganaoui Advanced Systems Engineering Laboratory National School of Applied SciencesIbn Tofail UniversityKenitra242Morocco LERMAB/IUT Longwy Institut CarnotNancy186France

Resin transfer molding(RTM)is among the most used manufacturing processes for composite ***,the resin cure is initiated by heat supply to the *** supplementary heat generated during the reaction can cause thermal gradients in the composite,potentially leading to undesired residual stresses which can cause shrinkage and *** the present numerical study of these processes,a one-dimensional finite difference method is used to predict the temperature evolution and the degree of cure in the course of the resin polymerization;the effect of some parameters on the thermal gradient is then analyzed,namely:the fiber nature,the use of multiple layers of reinforcement with different thermal properties and also the temperature cycle *** validity of this numerical model is tested by comparison with experimental and numerical results in the existing literature.

关键词： Cure RTM finite difference method thermal gradients residual stresses

GOAL: ZERO ENERGY BUILDING Exemplary Experience Based on the Solar Estate Solarsiedlung Freiburg am Schlierberg, Germany

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Journal of Green Building 2009年第4期4卷 93-100页

作者： mira Heinze Karsten Voss University of Wuppertal Department D ArchitectureBuilding Physics and Technical Services

Zero energy *** goal sounds simple and is presented excessively in variations all over the *** and environmental politics demand zero consumption as a long-term goal,marketing has discovered the concept and fi rst buildings and settlements aiming at balanced energy or emission budgets have been *** an example,the German Federal Government specifi es in its fi fth energy research programme(2005):For new buildings,the goal is to reduce the primary energy demand,*** energy demand for heating,domestic hot water,ventilation,air-conditioning,lighting and auxiliary energy,again by half compared to the current state of the *** long-term goal is zero-emission *** and the USA aim for zero carbon developments and net-zero energy buildings(DOE,2009)in political *** Vatican accepted the offer of climatic“indulgence”—and thus became the fi rst country in the world to completely compensate its carbon emission(Spiegel online,2007).Megaprojects in the growth regions of the Arabian Gulf and China advertise with a CO2-neutral balance.A Zero Carbon Community is to be created in Masdar,Abu Dhabi(Foster,2007),and the fi rst Chinese carbon-neutral ecocity was planned for Dongtan,Shanghai(Pearce,2009).Not only to aid international communication,but also to further the processes required to solve energy-related problems,it is essential that key words,central concepts,their usage and their relationships be clarifi *** article intends to contribute to this clarifi cation based on the monitored example of a solar *** zero energy building,equilibrium building,carbon neutral city—the accounting method varies,depending on motivation and point of *** the focus is on fi nite and scarce resources,energy is the currency;CO2-equivalent emissions are considered if global warming and public health is the issue;the cost of energy is what concerns a tenant paying for heating and electricity.A balance in one set of units can be

关键词： net zero energy zero emission solar estate solarsiedlung freiburg am schlierberg monitoring