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Non-integer Order Control Scheme for Pressurized Water Reactor Core Power

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Computers, Materials & Continua 2022年第7期72卷 651-662页

作者： ibrahim M.Mehedi Maher h.AL-Sereihy Asmaa Ubaid Al-Saggaf Ubaid M.Al-Saggaf Department of Electrical and Computer Engineering(ECE) King Abdulaziz UniversityJeddah21589Saudi Arabia Center of Excellence in Intelligent Engineering Systems(CEIES) King Abdulaziz UniversityJeddah21589Saudi Arabia

Tracking load changes in a pressurized water reactor(PWR)with the help of an efficient core power control scheme in a nuclear power station is very *** reason is that it is challenging to maintain a stable core power according to the reference value within an acceptable tolerance for the safety of *** overcome the uncertainties,a non-integer-based fractional order control method is demonstrated to control the core power of *** available dynamic model of the reactor core is used in this *** power is controlled using a modified state feedback approach with a non-integer integral scheme through two different approximations,CRONE(Commande Robuste d’Ordre Non Entier,meaning Non-integer orderRobust Control)and FOMCON(non-integer order modeling and control).Simulation results are produced using MATLAB■*** non-integer results are compared with an integer order PI(Proportional Integral)algorithm to justify the effectiveness of the proposed ***-spacemodel Core power control Non-integer control Pressurized water reactor PI controller CRONE FOMCON.

关键词： Sate-space model core power control non-integer control pressurized water reactor PI controller CRONE FOMCON

Effects of Eu3＋ and Dy3＋ doping or co-doping on optical and structural properties of BaB2Si2O8 phosphor for white LED applications

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Journal of Rare Earths 2016年第1期34卷 21-29页

作者：廖侹乔刘宏 R. hUSSIN Z. ibrahim K. DERAMAN h.O. LINTANG W.N.W ShAMSURI Phosphor Research Group Department of Physics Faculty of Seience Universiti Teknologi Malaysia Skudai 81310 Johor Malaysia State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China Catalytic Science and Technology Research Group Ibnu Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Skudai 81310 Johor Malaysia

A series of Eu3＋ and Dy3＋ doped/co-doped as well as un-doped BaB2Si2Os phosphors were synthesized via solid state reaction method. The PL result showed typical blue and green emission from Dy3＋ and red emission from Eu3＋. The f-f transitions in- volving the lanthanide ions along with dopant site occupancy were discussed thoroughly. Phonon assisted energy transfer process was observed from Eu3＋ to Dy3＋, which enhanced the emissions of Dy3＋. Combinations of the emissions from Eu3＋ and Dy3＋ showed a possible white to red tuneable emission on the CIE diagram. The white warmth emissions of the phosphor were revealed to be ad- justable through designing the dopant concentration and excitation wavelengths. An unusual energy transfer that originated from Eu3＋ to Dy3＋ was also discovered and the energy transfer mechanism was discussed. Proposed energy transfer mechanism was investigated using luminescence decay lifetime. All the phosphor exhibited efficient excitation in the UV range which matched well with the emissions from GaN-based LED chips. This presented the BaB2Si208 phosphor as a promising candidate for white LED applications. The effects of doping on the structural properties and the optical band gap of BaB2Si208 phosphor were also discussed in this study.

关键词： BaB2Si2O8:Eu3+/Dy3+ phosphor energy transfer rare earths

Stability evaluation of the Gümüshane-Akcakale cave by numerical analysis method

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Journal of Mountain Science 2019年第9期16卷 2150-2158页

作者： ALEMDAG Selcuk ZEYBEK halil ibrahim KULEKCI Gokhan Department of Geological Engineering Gumushane UniversityGumushane 29100Turkey Department of Geography Ondokuz Mayis UniversitySamsun 55105Turkey Department of Mining Engineering Gumushane UniversityGumushane 29100Turkey

The Ak?akale Cave is located in the vicinity of the Arsa neighborhood within the boundaries of the Ak?akale village, Gümü?hane, Turkey. The cave is rich in cave formations(stalactite, stalagmite, cave pearl, cave flower, wall travertines). Thus, the appropriateness of opening the cave to visitors to boost tourism is of importance for the local and national economy. This study analyzes the stability of the Ak?akale Cave using a numerical analysis method. According to the results of the total displacement analysis, there are displacements in the entrance, ceiling, and sidewalls of the cave ranging from 1 mm to 48 mm. It seems that the entrance, ceiling, and sidewalls of the cave face a high risk of local or sudden collapse. According to the deformation analysis of the length section of the cave examined, local collapses may occur especially in the first 75 m from the entrance of the cave. We believe that this situation would not carry a risk for the Arsa neighborhood for now. In conclusion, the results of the stability analysis and in-situ observations showed clear evidence of former and ongoing cave-ins(collapses) and the Ak?akale Cave faces a high risk of local or sudden collapse. Thus, although the Ak?akale Cave is one of the most prominent karst caves in Turkey, it seems to be not appropriate to open the cave to tourist visits.

关键词： Akcakale Cave Dripstone Finite element method Karst caves Numerical analysis

Optimal performance of water-oil axial jet pump in an egyptian offshore oil field

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Petroleum Research 2023年第4期8卷 561-571页

作者： A.A.A.Sheha K.A.ibrahim h.A.Abdalla I.M.Sakr Samy M.El-Behery Offshore Operations Department Section head PetroGulf Misr Petroleum Company10St.250 Sarayat El-MaadiCairoEgypt Mechanical Power Engineering Department Faculty of EngineeringMenoufia UniversityShebin El-KomEgypt

The jet pump is an artificial lift employed when the reservoir pressure declines and the well deviation *** use of computer well models for optimizing the oil well output has proven to be a suc-cessful strategy,and has helped increasing the efficiency and production of numerous *** objective of this study was to use a production optimization technique that achieves some improve-ments,and recommend approaches toward increasing the oil well *** effects of the motive fluid flow rate and pressure on the oil production rate were investigated to determine the optimal in-jection rate and pressure on the performance of the deep well water-oil axial ***,the effects of the well-head pressure,water cut,and roughness of tubing on oil production of this jet pump type were *** results revealed that the impact on the oil lift performance is *** oil production increased by 19.43%,and the optimal economic value for the injection rate and pressure for the GA-1A well are 744.44 BFPD and 2722.22 psig,*** summary,increasing the tubing roughness decreased the well's total liquid ***,maintaining the well integrity is a very important factor because not doing so can lower the productivity by up to 20%-25%.

关键词： Water-oil jet pump PROSPER Performance Roughness Oil production

Controlled growth and composition of multivariate metal-organic frameworks-199 via a reaction-diffusion process

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Nano Research 2021年第2期14卷 423-431页

作者： Razan lssa Fayrouz Abou ibrahim Mazen Al-Ghoul Mohamad hmadeh Department of Chemistry American University of BeirutP.O.Box 11-0236RiadEl-Solh 11072020BeirutLebanon Department of Chemistry McGill University801 Sherbrooke Street WestMontreal H2A 0B8Canada

In this paper,we exploit our prior successful synthesis of MOF-199 single crystals using the reaction-diffusion framework(RDF),to synthesize multivariate metal-organic frameworks(MTV-MOFs)version with enhanced *** MTV-MOFs are synthesized by creating defects within the MOF-199 crystal structure by integrating organic linkers entailing different functional ***,5-aminoisophthalic acid(Nh_(2)-BDC)and 5-hydroxyisophthalic acid(Oh-BDC)are separately mixed with 1,3,5-benzenetricarboxylic acid(BTC)in three different starting ratios of X-BDC:BTC(1:3,1:1)and(3:1).The effects of this linker on the morphology of the synthesized MTV-MOFs,their thermal stability,and their surface area are *** extent of the incorporation of the linkers in the framework is elucidated via^(1)h-NMR spectroscopy and it is shown that the incorporation varies as a function of the location along the tubular reactor,a characteristic of *** enhanced properties of the synthesized MTV-MOFs are further demonstrated by measuring its adsorptive capability for methylene blue(MB)and rhodamine B(Rh B)in aqueous solution,and compared with that of the as-synthesized *** kinetic and thermodynamic studies reveal that MTV-MOFs with the ratio of X-BDC:BTC(1:1)exhibit the best uptakes of MB(263 mg/g)for X=Oh and Rh B(156 mg/g)for X=Nh_(2).The adsorbents are also easily regenerated for three consecutive cycles without losing their *** finally demonstrate that MTV-MOFs can be designed to tune the dye removal selectivity and enhance the removal capacity of both MB and RhB in a binary aqueous solution of these dyes.

关键词： reaction-diffusion framework(RDF) multivariate metal-organic frameworks(MTV-MOFs) adsorption methylene blue(MB) rhodamine B(Rh B)

(Sm/Eu/Tm)^(3+) doped tantalum semiconductor system for photovoltaic and electrochemical functionality amplification

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Journal of Rare Earths 2024年第8期42卷 1586-1594,I0007页

作者： Shaan Bibi Jaffri Khuram Shahzad Ahmad Isaac Abrahams ibrahim A.A Materials and Environmental Chemistry Lab Lab-E21Department of Environmental SciencesFatima Jinnah Women UniversityRawalpindiPakistan School of Physical and Chemical Sciences Queen Mary University of LondonLondonUnited Kingdom Department of Botany and Microbiology College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

This work reports the synthesis,characterization,and energy focused applications of the novel lanthanides co-doped tantalum pentoxide hetero-system(Sm^(3+)-Eu^(3+)-Tm^(3+):Ta_(2)O_(5)).Ln^(3+)-doped Ta_(2)O_(5) express excellent opto-electronic features reflected by the narrow band gap energy of 3.87 *** vibrations confirm the presence of Ta-O-Ta and Ta-O *** synthesized system possesses orthorhombic geometry with 59.46 nm particle *** the smoother and compact morphology,the synthesized material succeeds in augmenting the performance of different systems aimed at energy *** ambient perovskite solar cell device fabricated with the Ln^(3+)-doped Ta_(2)O_(5) as an electron transport layer excels in achieving an efficiency and fill factor of 14.17% and 76% under artificial *** device was marked by the negligible hysteresis behavior showing profound photovoltaic *** electrochemical activity of the Ln^(3+)-doped Ta_(2)O_(5) decorated electrode was evaluated for electrical charge storage potential with pseudocapacitive behavior,With the highest specific capacitance of 355.39 F/g and quicker ionic diffusion rate,the designed electrode excels conventionally used ***-catalysis of water with Ln^(3+)-doped Ta_(2)O_(5) material indicates its capacity for h_(2) production with the lowest overpotential and Tafel slope values of 148 and 121.2 mV/dec,while the O_(2) generation is comparatively *** the stable electrochemical output,this rare earth modified material has the potential to replace conventionally used environmentally perilous and costly materials.

关键词： Lanthanide doping Rare earth materials Perovskite solar cells Supercapacitors Water splitting

Synchronization Phenomena Investigation of a New Nonlinear Dynamical System 4D by Gardano’s and Lyapunov’s Methods

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Computers, Materials & Continua 2021年第3期66卷 3311-3327页

作者： Abdulsattar Abdullah hamad Ahmed S.Al-Obeidi Enas h.Al-Taiy Osamah ibrahim Khalaf Dac-Nhuong Le School of Mathematics Madurai Kamaraj UniversityMadurai625021India Specialty of Mathematics Gifted School of NinevehMosulIraq Al-Nahrain University Baghdad70030Iraq Institute of Research and Development Duy Tan UniversityDanang550000Vietnam Faculty of Information Technology Duy Tan UniversityDanang550000Vietnam

Synchronization is one of the most important characteristics of dynamic *** this paper,the authors obtained results for the nonlinear systems controller for the custom Synchronization of two 4D *** findings have allowed authors to develop two analytical approaches using the second Lyapunov(Lyp)method and the *** the Gardano method does not involve the development of special positive Lyp functions,it is very efficient and convenient to achieve excessive systemSYCR *** is overcome by using Gardano and overcoming some problems in *** we get a great investigation into the convergence of error dynamics,the authors in this paper are interested in giving numerical simulations of the proposed model to clarify the results and check them,an important aspect that will be studied is Synchronization Complete hybrid SYCR and anti-Synchronization,by making use of the Lyapunov expansion analysis,a proposed control method is developed to determine the *** basic idea in the proposed way is to receive the evolution of between two ***,the present model has been applied and showing in a new attractor,and the obtained results are compared with other approximate results,and the nearly good coincidence was obtained.

关键词： Chaos Lu model anti-synchronization hybrid synchronization Gardano’s method nonlinear dynamical system

Identification of Stochastic Nature of Yarn hairiness

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Journal of Donghua University(English Edition) 2006年第5期23卷 154-160页

作者： MILITK■ Ji■ ibrahim Sayed KRUPINCOVA Gabriela Department of Textile Materials Textile Faculty Technical University of Liberec 46117 Liberec Czech Republic Department of Textile Technologies Textile Faculty Technical University of Liberec 46117 Liberec Czech Republic

Yam hairiness is a complex concept, which generally cannot be completely defined by a single figure. hairiness can be considered as the fiber ends and loops standing out from the main compact yarn body. Uster hairiness system characterizes the hairiness by h value, i.e. the mean value of the total length of all hairs within one centimeter of yarn. The raw data hI are in fact realization of spatial process （hairiness spatial process -- hSP） and can be used for more complex evaluation of hairiness characteristics in the space and frequency domain. The main aim of this contribution is description of some tools for spatial characterization of yarn hairiness. The simple methods for complex characterization of lISP statistical behavior （stationarity, independence, linearity etc. ） are presented. The techniques based on the embedding dimension and correlation integral or long-range dependences evaluation are discussed. The selected methods are core of hYARN program in MATLAB. Application of this program for deeper characterization of artificial data and cotton type yam are shown.

关键词： yarn hairiness hairiness spatial process long and short range dependencies hurst exponent.

The optimum conditions for methanol conversion to dimethyl ether over modified sulfated zirconia catalysts prepared by different methods

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燃料化学学报 2021年第1期49卷 63-71页

作者： Doaa S.EL-DESOUKI Amina h.ibrahim Samira M.ABDELAZIM Noha A.K.ABOUL-GhEIT Dalia R.ABDEL-hAFIZAR Processes Development Department EPRICairo 11727Egypt Refining Department EPRICairo 11727Egypt

Sulfated zirconia(SZ)and two promoted 1% Mn/SZ catalysts which have been prepared via sol gel(Mn/SZ-S)and impregnation(Mn/SZ-I)methods were *** morphology of the catalysts was characterized by XRD,BET,Nh3-TPD,ICP,SEM and FT-IR *** conversion of methanol to dimethyl ether and hydrocarbons was carried out in the temperature range of 120−300℃.The Mn/SZ-S showed the highest activity due to the high surface area with suitable *** optimum condition of Mn/SZ-S catalyst was investigated at 200℃ and LhSV of 0.02 h^−1 in a time range from 30 to 210 *** was found that the total conversion decreased from 80.18% to 53.26% at 210 *** reusability of this catalyst was studied at the optimum condition up till four cycles for 1 *** characterization of the reused catalyst showed a significant change in the structure and surface acidity due to the blockage of the surface acid sited by carbonaceous materials.

关键词： catalysts dehydration DME sulfate content sulfated zirconia