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An adaptive neuro-fuzzy sliding mode controller for MiMO systems with disturbance

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Chinese Journal of Chemical Engineering 2017年第4期25卷 463-476页

作者： Mahmoud M.Saafan mohamed M.Abdelsalam mohamed S.Elksas Sabry f.Saraya fayez f.G.Areed Computers and Control Systems Engineering Department Faculty of EngineeringMansoura UniversityEgypt

This paper introduces the mathematical model of ammonia and urea reactors and suggested three methods for designing a special purpose controller. The first proposed method is Adaptive model predictive controller, the second is Adaptive Neural Network Model Predictive Control, and the third is Adaptive neuro-fuzzy sliding mode controller. These methods are applied to a multivariable nonlinear system as an ammonia–urea reactor system. The main target of these controllers is to achieve stabilization of the outlet concentration of ammonia and urea, a stable reaction rate, an increase in the conversion of carbon monoxide(CO) into carbon dioxide(CO_2) to reduce the pollution effect, and an increase in the ammonia and urea productions, keeping the NH_3/CO_2 ratio equal to 3 to reduce the unreacted CO_2 and NH_3, and the two reactors' temperature in the suitable operating ranges due to the change in reactor parameters or external disturbance. Simulation results of the three controllers are compared. Comparative analysis proves the effectiveness of the suggested Adaptive neurofuzzy sliding mode controller than the two other controllers according to external disturbance and the change of parameters. Moreover, the suggested methods when compared with other controllers in the literature show great success in overcoming the external disturbance and the change of parameters.

关键词： disturbance sliding ammonia stabilization outlet predictive monoxide dioxide overcome steam

Vertical load capacities of roof truss cross members

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international Journal of Mining Science and Technology 2016年第3期26卷 517-520页

作者： Gearhart David f. mohamed Khaled Morsy Office of Mine Safety & Health Research National Institute for Occupational Safety & Health

Trusses used for roof support in coal mines are constructed of two grouted bolts installed at opposing forty-five degree angles into the roof and a cross member that ties the angled bolts together. The load on the cross member is vertical, which is transverse to the longitudinal axis, and therefore the cross member is loaded in the weakest direction. Laboratory tests were conducted to determine the vertical load capacity and deflection of three different types of cross members. Single-point load tests, with the load applied in the center of the specimen and double-point load tests, with a span of 2.4 m, were conducted. for the single-point load configuration, the yield of the 25 mm solid bar cross member was nominally 98 kN of vertical load, achieved at 42 cm of deflection. for cable cross members, yield was not achieved even after 45 cm of deflection. Peak vertical loads were about 89 kN for 17 mm cables and67 kN for the 15 mm cables. for the double-point load configurations, the 25 mm solid bar cross members yielded at 150 kN of vertical load and 25 cm of deflection. At 25 cm of deflection individual cable strands started breaking at 133 and 111 kN of vertical load for the 17 and 15 mm cable cross members respectively.

关键词： Roof truss Coal mining Ground control Load capacity Roof support

Power swing and voltage collapse identification schemes for correct distance relay operation in power system

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Journal of Central South University 2013年第4期20卷 988-1000页

作者： Ahmad f. Abidin Azah mohamed Hussain Shareef Department of Electrical Electronic and Systems Engineering Universiti Kebangsaan Malaysia

The new techniques were presented for preventing undesirable distance relay maloperation during voltage collapse and power swings in transmission grids. initially, the work focused on the development of a fast detection of voltage collapse and a three-phase fault at transmission lines by using under impedance fault detector (UifD) and support vector machine (SVM). Likewise, an intelligent approach was developed to discriminate a fault, stable swing and unstable swing, for correct distance relay operation by using the S-transform and the probabilistic neural network (PNN). To illustrate the effectiveness of the proposed techniques, simulations were carried out on the iEEE 39-bus test system using the PSS/E and MATLAB software.

关键词： under impedance fault detector distance relay fault voltage collapse

Molecular analysis and anticancer properties of two identified isolates,fusarium solani and Emericella nidulans isolated from Wady El-Natron soil in Egypt against Caco-2(ATCC) cell line

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Asian Pacific Journal of Tropical Biomedicine 2012年第11期2卷 863-869页

作者： Hala f mohamed University of Al-Azhar Faculty of Science(Girls Branch)Department of Botany and MicrobiologyYoussef Abbas Street

Objective:To characterize,identify and investigate the anticancer properties of two new soil fungal isolates,Emericella nidulansand fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2(ATCCj cell ***:Soil sample was cultured and two strains were chosen for morphological and phenotypical *** sequences of the 18s rRNA gene and the internal transcribed spacer region iTS of the two isolates were amplified by *** tree construction and analysis of the resulted multiple sequences from the two fugal isolates were also carried *** vitro anticancer activity of the two strains was done against colon Caco-2 cancer cell *** transcription — PCR was carried out to detect level of expression of p53 in Caco-2 cell ***:Hf.i displayed morphological and genotypic characteristics most similar to that of fusarium solani while Hf.2 was most similar to Emericella nidulans with high similarity of 99%and 97%*** multiple sequence alignment of the two fungal isolates showed that,the maximum identical conserved domains in the 18s rRNA genes were identified with the nucleotide regions of Slst to 399th base pairs,88th to 525th base pairs *** those in the iTS genes were identified with the nucleotide regions of 88th to 463rd and Slst to *** two isolates showed iCsub>50 value with（6.24±5.21） and（9.84±0.36） μ g/mL) concentrations respectively at *** transcription- PCR indicated that these cells showed high level of expression for p53 ***:The morphology and molecular analysis identified Hf.1 and Hf.2 to be fusarium solani and Emericella nidulans;new isolates of anticancer producing fungi from Wady El-Natroon city in *** with the two isolates caused P53 expression in Caco-2 cell *** two isolates can be used as an anticancer agents.

关键词： fungi Colon cancer Caco-2 Phylogenetic tree Anticancer property Multiple sequence analysis Anticancer agent Cell line

Low Temperature Growth of Vertically Aligned Carbon Nanotubes via floating Catalyst Chemical Vapor Deposition Method

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Journal of Materials Science & Technology 2011年第4期27卷 296-300页

作者： M.R.Atiyah D.R.Awang Biak f.Ahmadun i.S.Ahamad f.Mohd Yasin H.mohamed Yusoff Department of Chemical and Environmental Engineering Universiti Putra Malaysia

Synthesis of carbon nanotubes （CNTs） below 600℃ using supporting catalyst chemical vapor deposition method was reported by many research groups. However, the floating catalyst chemical vapor deposition received less attention due to imperfect nanotubes produced. in this work, the effects of varying the preheating temperature on the synthesis of CNT were investigated. The reaction temperature was set at 570℃. The preheating set temperature was varied from 150 to 400℃ at 50℃ interval. Three O-ring shape heating mantels were used as heating source for the preheater. in situ monitoring device was used to observe the temperature profile in the reactor. Benzene and ferrocene were used as the carbon source and catalyst precursor, respectively. Vertically aligned CNTs were synthesized when the preheating temperature was set at 400℃. When the preheating temperature was increased up to 400℃, both the length and the alignment of CNTs produced were improved.

关键词： Vertically aligned carbon nanotubes (CNTs) floating catalyst Low synthesistemperature Preheating set temperature

Morphological and physiological responses to drought stress of carob trees in Mediterranean ecosystems

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Journal of Arid Land 2023年第5期15卷 562-577页

作者： Khouloud ZAGOUB Khouloud KRiCHEN mohamed CHAiEB Lobna f MNif Laboratory of Ecosystems and Biodiversity in Arid Land of Tunisia Faculty of SciencesUniversity of SfaxSfax 3000Tunisia

The greatest failure rate of reforestation programs is basically related to water deficit,especially at the seedling ***,the main objective of this work is to investigate the responses of three accessions of carob trees(Ceratonia siliqua L.)with 2-year-old from different climate regions to drought generated by four water treatments:Tc(250 mm),T1(180 mm),T2(100 mm),and T3(50 mm).The first accession(A1)comes from the protected national park of ichkeul in northern *** zone belongs to the bioclimatic sub-humid *** second accession(A2)comes from Melloulech,located in the center-east of Tunisia,belonging to the bioclimatic semi-arid *** third accession(A3)comes from the mountain of Matmata,located in the south of Tunisia,belonging to the bioclimatic hyper-arid *** experiment was undertaken in a *** exchange indices(net photosynthesis(A),stomatal conductance(gs),transpiration rate(E),and internal CO_(2) concentration(Ci))were ***(Ψpd)and midday(Ψmd)leaf water potentials,relative soil water content(SWC),and morphological parameters(plant height(H),number of leaves(NL),number of leaflets(Nl),and number of branches(NB))were *** results showed that significant differences(Pfound between physiological and morphological parameters of each *** highest growth potential was recorded for Tc treatment in both accessions A1 and *** decreases in gs,E,Ci,and SWC were recorded with the increases in water stress applied from treatment T1 to *** and significant correlations were found between SWC andΨpd for all studied accessions.Ψpd andΨmd decreased as water stress increased,ranging from–0.96 to–1.50 MPa at sunrise and from–1.94 to–2.83 MPa at midday,respectively,under control and T3 *** accessions responded to drought through exhibiting significant changes in their physiological and morphological *** accessions A1 and A2 showed greater drought tol

关键词： Ceratonia siliqua L. water stress soil moisture stomatal conductance predawn leaf water potential minimum water potential

On-line CO,CO_2 emissions evaluation and(benzene, toluene, xylene) determination from experimental burn of tropical biomass

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Journal of Environmental Sciences 2015年第7期27卷 239-244页

作者： Mohammed f.Tawfiq mohamed Kheireddine Aroua Nik Meriam Nik Sulaiman Chemical Engineering Department Faculty of Engineering University of Malaya

Atmospheric pollution and global warming issues are increasingly becoming major environmental concerns. fire is one of the significant sources of pollutant gases released into the atmosphere; and tropical biomass fires, which are of particular interest in this study,contribute greatly to the global budget of CO and CO2. This pioneer research simulates the natural biomass burning strategy in Malaysia using an experimental burning facility. The investigation was conducted on the emissions（CO2, CO, and Benzene, Toluene, Ethylbenzene,Xylenes（BTEX）） from ten tropical biomass species. The selected species represent the major tropical forests that are frequently subjected to dry forest fire incidents. An experimental burning facility equipped with an on-line gas analyzer was employed to determine the burning emissions. The major emission factors were found to vary among the species, and the specific results were as follows. The moisture content of a particular biomass greatly influenced its emission pattern. The smoke analysis results revealed the existence of BTEX,which were sampled from a combustion chamber by enrichment traps aided with a universal gas sampler. The BTEX were determined by organic solvent extraction followed by GC/MS quantification, the results of which suggested that the biomass burning emission factor contributed significant amounts of benzene, toluene, and m,p-xylene. The modified combustion efficiency（MCE） changed in response to changes in the sample moisture ***, this study concluded that the emission of some pollutants mainly depends on the burning phase and sample moisture content of the biomass.

关键词： Emission Biomass Experimental BTEX CO CO2 GG/MS

Modeling and Optimization of Surface Roughness of Epoxy/Nanoparticles Composite Coating

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Computers, Materials & Continua 2022年第4期71卷 71-83页

作者： A.f.mohamed J.Abu Alsoud Mujahed Al-Dhaifallah Hegazy Rezk mohamed K.Hassan Department of Mechanical Engineering College of Engineering&Islamic Arch.Umm Alqura UniversityMakkahSaudi Arabia Department of Mechanical Engineering Faculty of EngineeringSohag UniversitySohagEgypt Department of Systems Engineering King Fahd University of Petroleum&MineralsDhahran31261KSA College of Engineering at Wadi Addawaser Prince Sattam Bin Abdulaziz UniversityAl-Kharj11911Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMinia UniversityMinia61517Egypt Department of Production Engineering and Design Faculty of EngineeringMinia UniversityMinia61517Egypt

in power plants,flue gases can cause severe corrosion damage in metallic parts such as flue ducts,heat exchangers,and *** is an effective technique to prevent this damage.A robust fuzzy model of the surface roughness(Ra and Rz)of flue gas ducts coated by protective composite coating from epoxy and nanoparticles was constructed based on the experimental *** proposed model consists of four nanoparticles(ZnO,ZrO2,SiO2,and NiO)with 2%,4%,6%,and 8%,*** surface methodology(RSM)was used to optimize the process parameters and identify the optimal conditions for minimum surface roughness of this coated *** prove the superiority of the proposed fuzzy model,the model results were compared with those obtained by ANOVA,with the coefficient of determination and the root-mean-square error(RMSE)used as *** Ra,for the first output response,using ANOVA,the coefficient-of-determination values were 0.9137 and 0.4037,respectively,for training and ***,for Rz,the second output response,the coefficient-of-determination results were 0.9695 and 0.4037,respectively,for training and *** the fuzzy modeling of Ra,for the first output response,the RMSE values were 0.0 and 0.1455,respectively,for training and *** values for the coefficient of determination were 1.00 and 0.9807,respectively,for training and *** results prove the superiority of fuzzy *** modeling the second output response Rz,the RMSE values were 0.0 and 0.0421,respectively,for training and testing,and the coefficient-of-determination values were 1.00 and 0.9959,respectively,for training and testing.

关键词： Materials coating nanoparticles modeling and optimization

Entropy and Entanglement in Master Equation of Effective Hamiltonian for Jaynes-Cummings Model

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Communications in Theoretical Physics 2009年第4期51卷 723-728页

作者： H.A.Hessian f.A.Mohammed A.-B.A.mohamed faculty of Science Assiut University

in this paper, we analytically solve the master equation for Jaynes-Cummings model in the dispersive regime including phase damping and the field is assumed to be initially in a superposition of coherent states. Using an established entanglement measure based on the negativity of the eigenvalues of the partially transposed density matrix we find a very strong sensitivity of the maximally generated entanglement to the amount of phase damping. Qualitatively this behavior is also reflected in alternative entanglement measures, but the quantitative agreement between different measures depends on the chosen noise model The phase decoherence for this model results in monotonic increase in the total entropy while the atomic sub-entropy keeps its periodic behaviour without any effect.

关键词： entanglement phase damping master equation superposition state