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湿地科学 2006年第4期4卷 247-252页

作者： Chee Kong Yap Ahmad ismail Abdul Rahim ismail Soon Guan Tan Department of Biology Faculty of Science University Putra Malaysia UPM 43400 Serdang Selangor Malaysia

The distribution and concentrations of Cd, Cu, Pb and Zn were determined in the gills and remaining soft tissues of Perna viridis collected from 12 geographical sites (10 from the west and 2 from the east coastal waters) of Peninsular Malaysia. All samples showed that the levels of Cd, Pb and Zn were generally higher in the gill than those in the remaining soft tissues. These results could be due to the fact that gills are the first organ of metal accumulation and larger surface area with mucus sheets in the organ. Since the mussel gill is a better accumulator of Cd, Pb and Zn of ambient seawater than remaining soft tissue, it is a potential indicator of ambient levels of dissolved metals in the ambient seawater. However, further validations based on laboratory conditions are needed.

关键词： gill heavy metals Perna viridis

Prediction of Compressive Strength of Biodegradable Mg–Zn/HA Composite via Response Surface Methodology and Its Biodegradation

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Acta Metallurgica Sinica(English Letters) 2016年第5期29卷 464-474页

作者： Loy Liang Soon Hussain Zuhailawati ismail Suhaina Brij Kumar Dhindaw Structural Materials Niche Area Group School of Materialsand Mineral Resources EngineeringEngineering CampusUniversiti Sains Malaysia14300 Nibong TebalPenangMalaysia School of Minerals Metallurgical and Materials EngineeringIndian Institute of Technology Bhubaneswar Bhubaneswar751007India

This work aimed to fabricate magnesium zinc/hydroxyapatite （Mg-Zn/HA） composite via powder metallurgy method and to develop a mathematical model to predict the compressive strength of the composite using response surface methodology method. The effect of various mechanical milling parameters, milling speed （200-300 r/rain）, ball-to-powder weight ratio （5-12.5） and HA content （2.6-10 wt%） on the compressive strength of Mg-Zn/HA composite was investigated. The model shows that high compressive strength of Mg-Zn/HA composite was achieved when the powders were prepared with high milling speed and ball-to- powder weight ratio and low HA content. The mathematical model was adequate with error percentage lower than 3.4%. The microstructure of Mg-Zn/HA composite with different process parameters revealed that fine microstructure was observed at high milling speed and ball-to-powder weight ratio while agglomeration of HA was found in composite with 10 wt% HA. The agglomeration of HA led to degradation of interfacial bonding strength between matrix and reinforcement phases and hence decreased the overall compressive strength of Mg-Zn/HA composite. Biodegradation test revealed that sample with higher HA content had more weight gain and there was more formation of hydroxyapatite. Mg-Zn/HA composite with 8 wt% HA was found to be the best candidate for implant application because it had considerable compressive strength and good biodegradation properties.

关键词： Powder metallurgy Magnesium-zinc alloy Hydroxyapatite Response surface methodology Biodegradation

Fractional Analysis of Thin Film Flow of Non-Newtonian Fluid

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 825-845页

作者： Farnaz ismail Mubashir Qayyum Syed Inayat Ali Shah Department of Mathematics Islamia College UniversityPeshawarPakistan Department of Sciences and Humanities National University of Computer&Emerging Sciences FASTLahorePakistan

Modeling and analysis of thin film flow with respect to magneto hydro dynamical effect has been an important theme in the field of fluid dynamics,due to its vast industrial *** analysis involves studying the behavior and response of governing equations on the basis of various parameters such as thickness of the film,film surface profile,shear stress,liquid velocity,volumetric flux,vorticity,gravity,viscosity among others,along with different boundary *** this article,we extend this analysis in fractional space using a homotopy based scheme,considering the case of a Non-Newtonian Pseudo-Plastic fluid for lifting and drainage on a vertical *** applying similarity transformations,the given problems are reduced to highly non-linear and inhomogeneous ordinary differential ***,fractional differential equations are obtained using basic definitions of fractional *** Homotopy Perturbation Method(HPM),along with fractional calculus is used for obtaining approximate *** quantities such as the velocity profile,volume flux and average velocity respectively for lift and drainage cases have been *** the best of our knowledge,the given problems have not been attempted before in fractional *** and convergence of the obtained solutions are confirmed by finding residual *** a physical perspective,a comprehensive study of the effects of various parameters on the velocity profile is also *** reveals that Stokes number St,non-Newtonian parameterand magnetic parameter M have inverse relationship with fluid velocity in lifting *** the drainage case,Stokes number St and non-Newtonian parameterhave direct relationship with fluid velocity,but magnetic parameter M shows inverse relationship with *** investigation also shows that the fractional parameterhas direct relationship with the fluid velocity in lifting case,while it has inverse relationship with velocity in the

关键词： Pseudo-plastic fluid magneto hydro dynamic fractional differential equation homotopy perturbation method

Cue hierarchy in the foraging behaviour of the brackish cladoceran Daphniopsis australis

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Journal of Oceanology and Limnology 2018年第6期36卷 2050-2060页

作者： MCCLOUD Clayton Leigh ismail Hasnun Nita SEURONT Laurent Australian Fisheries Management Authority CanberraAustralia School of Biology Universiti Teknologi MARASelangorMalaysia CNRS Univ.LilleUniv.Littoral Coe d'OpaleUMR 8187LOGLaboratoire d'Océnologie et de GésciencesF 62930 WimereuxFrance

Zooplankton communities are an essential component of marine and freshwater food webs. However, there is still a relative lack of information on how these organisms behaviourally respond to a range of abiotic and biotic stressors. Specifically, the behaviour of the cladoceran D aphniopsis australis, a species endemic to South-eastern Australian saline lakes and ponds, is still unknown despite its potential role in the structure and function of inland water ecosystems. The swimming behaviour of males, parthenogenetic females and epiphial females was investigated under various conditions and combinations of food and conspecific cues. In the absence of cues, males displayed the most extensive swimming behaviour, exploring all areas of the container, and swimming in a series of relatively straight trajectories. In contrast, females typically exhibited a hop-and-sink motion characterised by the alternation between short bursts of swimming and sinking phases. Both females spent long periods near the bottom of the container, but epiphial females appeared to be more active than parthenogenetic ones that rarely made an excursion in the water column. In the presence of cues, males and females showed abilities to detect infochemicals from food and conspecifics, but exhibited specific behavioural strategies. Males essentially increased their swimming speed in the presence of food and/or conspecific infochemicals, and this increase was independent on the source of the cues, i.e. food, conspecific or a mixture of food and conspecifics. In contrast, females exhibited cue hierarchies that were related to their sexual status. Parthenogenetic females swam faster in the presence of food and a mixture of food and conspecific infochemicals than in the presence of cue from the opposite sex, which did not significantly differ from control observations conducted in the absence of cues. Epiphial females decreased their swimming speed in the presence of cues, with the most significant behavi

关键词： zooplankton chemical cues sex-specific behaviour

Blast-induced ground vibration prediction in granite quarries:An application of gene expression programming,ANFIS,and sine cosine algorithm optimized ANN

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International Journal of Mining Science and Technology 2021年第2期31卷 265-277页

作者： Abiodun ismail Lawal Sangki Kwon Olaide Sakiru Hammed Musa Adebayo Idris Department of Energy Resources Engineering Inha UniversityIncheon 22212Republic of Korea Department of Mining Engineering Federal University of TechnologyAkureNigeria Department of Physics Federal UniversityOye-EkitiNigeria Division of Mining and Geotechnical Engineering Department of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of Technology97187 LuleåSweden

Blasting of rocks has intrinsic environmental impacts such as ground vibration,which can interfere with the safety of lives and ***,accurate prediction of the environmental impacts of blasting is imperative as the empirical models are not accurate as evident in the ***,there is need to consider some robust predictive models for accurate prediction *** expression programming(GEP),adaptive neuro-fuzzy inference system(ANFIS),and sine cosine algorithm optimized artificial neural network(SCA-ANN)models are proposed for predicting the blast-initiated ground vibration in five granite *** input parameters into the models are the distance from the point of blasting to the point of measurement(D),the weight of charge per delay(W),rock density(q),and the Schmidt rebound hardness(SRH)value while peak particle velocity(PPV)is the targeted output.100 datasets were used in developing the proposed *** performance of the proposed models was examined using the coefficient of determination(R2)and error *** R2 values obtained for the GEP,ANFIS,and SCA-ANN models are 0.989,0.997,and 0.999,respectively,while their errors are close to *** proposed models are compared with an empirical model and are found to outperform the empirical model.

关键词： Artificial intelligence Blasting Rock density Comminution Environmental impacts Sensitivity analysis

Effect of Synthesis Technique and Carbonate Content on the Crystallinity and Morphology of Carbonated Hydroxyapatite

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Journal of Materials Science & Technology 2013年第8期29卷 761-764页

作者： Chia Ching Kee Hanafi ismail Ahmad Fauzi Mohd Noor School of Materials and Mineral Resources Engineering Engineering CampusUniversiti Sains Malaysia14300 Nibong TebalPenangMalaysia

The syntheses of nanosized carbonated hydroxyapatite （CHA） were performed by comparing dropwise and direct pouring of acetone solution of Ca（NO3）2·4H2O into mixture of （NH4）2HPO4 and NH4HCO3 at room temperature controlled at pH 11. Direct pouring method was later applied to study the increment of carbonate content in syntheses. The as-synthesized powders were characterized by various characterization techniques. The crystallographic results of the produced powders were obtained from X-ray diffraction analysis, whilst the carbonate content in the produced powders was determined by the CHNS/O elemental analyzer. Fourier transform infrared analysis confirmed that the CHA powders formed were B-type. Field emission scanning electron microscopy revealed that the powders were highly agglomerated in nanosized range and hence energy filtered transmission electron microscopy was employed to show elongated particles which decreased with increasing carbonate content.

关键词： Bioceramic Carbonated hydroxyapatite Dropwise Direct pouring

Diffusion Monte Carlo calculations on LaB molecule

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Chinese Physics B 2018年第9期27卷 241-246页

作者： Nagat Elkahwagy Atif ismail S M A Maizet K R Mahmoud Department of Physics Faculty of Science Kafrelsheikh University Kafr El-Sheikh Egypt Department of Physics Faculty of Applied Sciences Umm AI Qura University Makkah Saudi Arabia Department of Physics Faculty of Science Menoufia University Shebin EI-Kom Egypt

Potential energy curves for the lowest electronic states of LaB and LaB- have been calculated by ab initio *** diffusion Monte Carlo method has been employed in combination with three different trial functions. Spectroscopic constants have also been numerically derived for the neutral molecule and compared with the only available theoretical work;^（[19]） however, predictions are provided for the corresponding constants for the anionic species which have not been reported yet. Our calculations suggest the high spin quintet state of LaB as the ground state with the triplet state higher in energy irrespective of the type of the functional used. This suggestion is in good accordance with the previous theoretical results calculated at B3LYP/LANL2DZ level of theory, whereas it contradicts with the prediction based upon B3LYP/SDD calculations in the same study. Moreover, variations of the permanent dipole moments as a function of the internuclear separations for the two electronic states of the neutral molecule have been studied and analyzed.

关键词： potential energy curve lanthanum boride diffusion Monte Carlo dipole moment

Neural network control for earthquake structural vibration reduction using MRD

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1171-1182页

作者： Khaled ZIZOUNI Ley la FALI Younes SADEK ismail Khalil BOUSSERHANE ArcihPEL Laboratory University TAHRI MohammedBecharPB 417Algeria FIMAS Laboratory University TAHRJ MohammedBecharPB 417Algeria Laboratory of Smart-Grid and Renewable Energies University TAHRI MohammedBecharPB 417Algeria

Structural safety of building particularly that are intended for exposure to strong earthquake loads are designed and equipped with high technologies of control to ensure as possible as its protection against this brutal load. One of these technologies used in the protection of structures is the semi-active control using a Magneto Rheological Damper device. But this device need an adequate controller with a robust algorithm of current or tension adjustment to operate which is further discussed in the following of this paper. In this study, a neural network controller is proposed to control the MR damper to eliminate vibrations of 3-story scaled structure exposed to Tohoku 2011 and Boumerdes 2003 earthquakes. The proposed controller is derived from a linear quadratic controller designed to control an MR damper installed in the first floor of the structure. Equipped with a feedback law the proposed control is coupled to a clipped optimal algorithm to adapt the current tension required to the MR damper adjustment. To evaluate the performance control of the proposed design controller, two numerical simulations of the controlled structure and uncontrolled structure are illustrated and compared.

关键词： MR damper semi-active control earthquake vibration neural network linear quadratic control

Strain effect on graphene nanoribbon carrier statistic in the presence of non-parabolic band structure

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Chinese Physics B 2016年第9期25卷 480-483页

作者： N A Izuani Che Rosid M T Ahmadi Razali ismail Department of Electronics and Computer Engineering Faculty of Electrical EngineeringUniversiti Teknologi Malaysia Nanoelectronic Group Physics DepartmentFaculty of ScienceUrmia University

The effect of tensile uniaxial strain on the non-parabolic electronic band structure of armchair graphene nanoribbon（AGNR） is *** addition,the density of states and the carrier statistic based on the tight-binding Hamiltonian are modeled *** is found that the property of AGNR in the non-parabolic band region is varied by the *** tunable energy band gap in AGNR upon strain at the minimum energy is described for each of n-AGNR families in the non-parabolic *** behavior of AGNR in the presence of strain is attributed to the breakable AGNR electronic band structure,which varies the physical properties from its *** linear relation between the energy gap and the electrical properties is featured to further explain the characteristic of the deformed AGNR upon strain.

关键词： strain graphene nanoribbon uniaxial strain current–voltage characteristic

Classical state feedback controller for nonlinear systems using mean value theorem： closed Ioop-FOC of PMSM motor application

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Frontiers in Energy 2015年第4期9卷 413-425页

作者： Abrar ALLAG Abdelhamid BENAKCHA Meriem ALLAG ismail ZEIN Mohamed Yacine AYAD LGEB Laboratory Department of Electrical Engineering University of Biskra Biskra BP 145 Algeria R&D Industrial Hybrid Vehicle Applications Belfort 90010 France

The problem of state feedback controllers for a class of Takagi-Sugeno （T-S） Lipschitz nonlinear systems is investigated. A simple systematic and useful synthesis method is proposed based on the use of the differential mean value theorem （DMVT） and convex theory. The proposed design approach is based on the mean value theorem （MVT） to express the nonlinear error dynamics as a convex combination of known matrices with time varying coefficients as linear parameter varying （LPV） systems. Using the Lyapunov theory, stability conditions are obtained and expressed in terms of linear matrix inequalities （LMIs）. The controller gains are then obtained by solving linear matrix inequalities. The effectiveness of the proposed approach for closed loop-field oriented control （CL-FOC） of permanent magnet synchronous machine （PMSM） drives is demonstrated through an illustrative simulation for the proof of these approaches. Furthermore, an extension for controller design with parameter uncertainties and perturbation performance is discussed.

关键词： Takagi-Sugeno (T-S) fuzzy systems sectornonlinearity nonlinear controller linear matrix inequality(LMI) approach differential mean value theorem (DMVT),field oriented control (FOC) linear parameter varying(LPV)