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multiscale edge detection of noisy images using wavelets

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Journal of Harbin Institute of Technology(New Series) 2007年第5期14卷 737-740页

作者： farooq m College of Automation Engineering Nanjing University of Aeronautics & Astronautics

The classical edge detectors work fine with the high quality pictures, but often are not good enough for noisy images because they cannot distinguish edges of different significance. The paper presented a novel approach to multiscale edge detection for noisy images using wavelet transforms based on Lipschitz regularity coefficients and a cascade algorithm. The relationship between wavelet transform and Lipschitz regularity was established. The proposed wavelet based edge detection algorithm combined the coefficients of wavelet transforms along with a cascade algorithm which significantly improves the result. The comparison between the proposed method and the classical edge detectors was carried out. The algorithm was applied to various images and its performance was discussed. The results of edge detection of contaminated images using the proposed algorithm show that it works better than the classical edge detectors.

关键词： edge detection wavelet lipschitz regularity cascade algorithm

Improved hybrid position/force controller design of a flexible robot manipulator using a sliding observer

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Journal of Systems Engineering and Electronics 2009年第1期20卷 146-158页

作者： farooq m Wang Daobo Dar N. U Coll. of Automation Engineering Nanjing Univ. of Aeronautics & Astronautics Nanjing 210016 P. R. China Coll. of mechanical Engineering Univ. of Engineering and Technology Taxila Pakistan

An improved hybrid position/force controller design of a flexible robot manipulator is presented using a sliding observer. The friction between the end effector and the environment is considered and compensated. For systematic reasons the controller is designed taking into consideration the rigid link subsystems and the flexible joints. The proposed control system satisfies the stability of the two subsystems and copes with the uncertainty of robot dynamics. A sliding observer is designed to estimate the time derivative of the torque applied as input to the rigid part of the robot. For the stability of the observer, it is assumed that the uncertainty of the observed system is bounded. A mRAC algorithm is used for the estimation of the friction forces at the contact point between the end effector and the environment. Finally simulation and experimental results are given, to demonstrate the effectiveness of the proposed controller.

关键词： force control sliding control Lyapunov stability robot end effector friction force.

Note on characteristics of homogeneous-heterogeneous reaction in flow of Jeffrey fluid

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Applied mathematics and mechanics(English Edition) 2015年第10期36卷 1319-1328页

作者： m.farooq A.ALSAEDI T.HAYAT Department of mathematics Quaid-i-Azam University Nonlinear Analysis and Applied mathematics (NAAm) Research Group Faculty of Science King Abdulaziz University

This letter describes the characteristics of homogeneous-heterogeneous re- action in the boundary layer flow of a Jeffrey fluid due to an impermeable horizontal stretching sheet. An analysis is carried out through the similar values of reactant and auto catalyst diffusion coefficients. Heat released by the reaction is not accounted. The exact solution for the flow of the Jeffrey fluid is constructed. The series solution for the concentration equation is derived. The velocity and concentration fields reflecting the impact of interesting parameters are plotted and examined.

关键词： Jeffrey fluid stretching sheet homogeneous-heterogeneous reaction

mixed Convective Viscoelastic Nanofluid Flow Past a Porous media with Soret–Dufour Effects

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Communications in Theoretical Physics 2016年第7期65卷 133-142页

作者： m.Ramzan Farhan Yousaf m.farooq Jae Dong Chung Department of Computer Science Bahria University Department of mathematics Faculty of Computing Capital University of Science and Technology Department of mathematics Riphah International University Department of mechanical Engineering Sejong University

The present study is carried out to see the thermal-diffusion(Dufour) and diffusion-thermo(Soret) effects on the mixed convection boundary layer flow of viscoelastic nanofluid flow over a vertical stretching surface in a porous medium. Optimal homotopy analysis method(OHAm) is best candidate to handle highly nonlinear system of differential equations obtained from boundary layer partial differential equations via appropriate transformations. Graphical illustrations depicting different physical arising parameters against velocity, temperature and concentration distributions with required discussion have also been added. Numerically calculated values of skin friction coefficient, local Nusselt and Sherwood numbers are given in the form of table and well argued. It is found that nanofluid velocity increases with increase in mixed convective and viscoelastic parameters but it decreases with the increasing values of porosity parameter. Also, it is observed that Dufour number has opposite behavior on temperature and concentration profiles.

关键词： mixed convection porous media nanofluid flow soret-dufour effects

mHD stagnation point flow by a permeable stretching cylinder with Soret-Dufour effects

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Journal of Central South University 2015年第2期22卷 707-716页

作者： m.Ramzan m.farooq T.Hayat A.Alsaedi J.Cao Department of mathematics Faculty of Computing Mohammad Ali Jinnah UniversityIslamabad Campus 44000 Pakistan Department of mathematics Quaid-I-Azam University 45320 Islamabad 44000 Pakistan Nonlinear Analysis and Applied mathematics (NAAm) Research Group Faculty of ScienceKing Abdulaziz University P.O.Box 80203 Jeddah 21589 Saudi Arabia Department of mathematics and Research Center for Complex Systems and Network Sciences Southeast University

Combined effects of Soret(thermal-diffusion) and Dufour(diffusion-thermo) in mHD stagnation point flow by a permeable stretching cylinder were studied. Analysis was examined in the presence of heat generation/absorption and chemical reaction. The laws of conservation of mass, momentum, energy and concentration are found to lead to the mathematical development of the problem. Suitable transformations were used to convert the nonlinear partial differential equations into the ordinary differential equations. The series solutions of boundary layer equations through momentum, energy and concentration equations were *** of the developed series solutions was discussed via plots and numerical values. The behaviors of different physical parameters on the velocity components, temperature and concentration were obtained. Numerical values of Nusselt number, skin friction and Sherwood number with different parameters were computed and analyzed. It is found that Dufour and Soret numbers result in the enhancement of temperature and concentration distributions, respectively.

关键词： stagnation point flow Soret-Dufour effects stretching cylinder suction/injection chemical reaction

Surface-type humidity sensor based on cellulose-PEPC for telemetry systems

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Journal of Semiconductors 2011年第1期32卷 103-107页

作者： Kh.S.Karimov m.Saleem T.A.Qasuria m.farooq GIK Institute of Engineering Sciences and Technology physical Technical Institute Aini St.299/1Dushanbe734063Tajikistan

Au/cellulose-PEPC/Au surface-type humidity sensors were fabricated by drop-casting cellulose and poly-N-epoxypropylcarbazole （PEPC） blend thin films. A blend of 2wt% of each cellulose and PEPC in benzol was used for the deposition of humidity sensing films. Blend films were deposited on glass substrates with preliminary deposited surface-type gold electrodes. Films of different thicknesses of cellulose and PEPC composite were deposited by drop-casting technique. A change in electrical resistance and capacitance of the fabricated devices was observed by increasing the relative humidity in the range of 0-95% RH. It was observed that the capacitances of the sensors increase, while their resistances decrease with increasing the relative humidity. The sensors were connected to op-amp square wave oscillators. It was observed that with increasing the relative humidity, the oscillator＇s frequencies were also increased in the range of 4.2-12.0 kHz for 65μm thick film sample, 4.1-9.0 kHz for 88μm thick film sample, and 4.2-9.0 kHz for 210μm sample. Effects of film thickness on the oscillator＇s frequency with respect to humidity were also investigated. This polymer humidity sensor controlled oscillator can be used for short-range and long-range remote systems at environmental monitoring and assessment of the humidity level.

关键词： surface-type sensor: cellulose poly-N-epoxvoropylcarbazole humidity sensor controlled oscillator

Investigations of Viscous Dissipation in Stagnation Point Flow Past a Stretchable Riga Wall: modern Analysis of Heat Transport

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Communications in Theoretical Physics 2019年第4期71卷 377-383页

作者： Aisha Anjum N.A.mir m.farooq m.Javed S.Ahmad Department of mathematics Riphah International University

This article scrutinizes the features of viscous dissipation in the stagnation point ?ow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat ?ux model. Viscous dissipation is carried out in Cattaneo-Christov diffusion analysis for the ?rst time in this letter. As a result of Cattaneo-Christov model, some extra terms of viscous dissipation are appeared in the energy equation. These extra terms of viscous dissipation are missing in the literature. On the utilization of suitable transformations, the equations governing the problem are reduced under the boundary layer approximation into the non-linear and dimensionless ordinary differential equations. Convergent approach is utilized to solve the dimensionless governing equations. The solution thus acquired is used to highlight the effects of emerging parameters on velocity distribution and ?uid's temperature through the graphs. Features of the drag force(or skin friction co-e?cient) are graphically interpreted. It is noticed that the presence of modi?ed Hartman number helps to reduce the ?uid's temperature but enhances the velocity pro?le. Further an enlargement in the value of thermal time relaxation parameter helps to decrease the temperature distribution.

关键词： stagnation point Cattaneo-Christov theory Riga plate linear stretching viscous dissipation

mass spectrometry detection of basic drugs in fast chiral analyses with vancomycin stationary phases

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Journal of Pharmaceutical Analysis 2018年第5期8卷 324-332页

作者： Hongyue Guo m.farooq Wahab Alain Berthod Daniel W.Armstrong Department of Chemistry and Biochemistry University of Texas at Arlington Institut des Sciences Analytiques CNRS Université de Lyon 1

Current trends in chiral analysis of pharmaceutical drugs are focused on faster separations and higher separation efficiencies, Core-shell or superficially porous particles （SPP） based chiral stationary phases （CSPs） provide reduced analysis times while maintaining high column efficiencies and sensitivity. In this study, mobile phase conditions suitable for chiral analyses with electrospray ionization LC-mS were systematically investigated using vancomycin as a representative CSP. The performance of a 2.7 μm SPP based vancomycin CSP （SPP-V） 10 cm ×0.21 cm column was compared to that of a corresponding 5 μm fully porous particles based analogue column. The results demonstrated that the SPP-V column provides higher efficiencies, 2-5 time greater sensitivity and shorter analysis time for a set of 22 basic pharma- ceutical drugs. The SPP-V was successfully applied for the analysis of the degradation products of racemic citalopram whose enantiomers could be selectively identified by mS.

关键词： mass spectrometry detection Chiral separation Basic drugs Beta-blockers Superficially porous particle Fully porous particle Fast separation Vancomycin

Ag/PEPC/NiPc/ZnO/Ag thin film capacitive and resistive humidity sensors

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Journal of Semiconductors 2010年第5期31卷 45-50页

作者： Kh.S.Karimov Kuan Yew Cheong m.Saleem Imran murtaza m.farooq Ahmad Fauzi mohd Noor GIK Institute of Engineering Sciences and Technology TopiDistrict SwabiNWFP 23640Pakistan Physical Technical Institute of Academy of Sciences Rudaki Ave 33Dushanbe734025Tajikistan School of materials & mineral Resources Engineering Engineering CampusUniversiti Sains Malaysia14300 Nibong TebalPenangMalaysia

A thin film of blended poly-N-epoxypropylcarbazole（PEPC）（25 wt.%）,nickel phthalocyanine（NiPc）（50 wt.%） and ZnO nano-powder（25 wt.%） in benzene（5 wt.%） was spin-coated on a glass substrate with silver electrodes to produce a surface-type Ag/PEPC/NiPc/ZnO/Ag capacitive and resistive *** with two different PEPC/NiPc/ZnO film thicknesses（330 and 400 nm） were fabricated and *** effects of humidity on capacitance and resistance of the Ag/PEPC/NiPc/ZnO/Ag sensors were investigated at two frequencies of the applied voltage：120 Hz and 1 *** was observed that at 120 Hz under humidity of up to 95%RH the capacitance of the sensors increased by 540 times and resistance decreased by 450 times with respect to humidity conditions of 50%RH. It was found that the sensor with a thinner semiconducting film（330 nm） was more sensitive than the sensor with a thicker film（400 nm）.The sensitivity was improved when the sensor was used at a lower frequency as compared with a high *** is assumed that the humidity response of the sensors is associated with absorption of water vapors and doping of water molecules in the semiconductor blend *** had been proven by simulation of the capacitance-humidity relationship.

关键词： organic semiconductor poly-N-epoxypropylcarbazole nickel phthalocyanine nano-powder ZnO sensor