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Four-dimensional parameter estimation of plane waves using swarming intelligence

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Chinese Physics B 2014年第7期23卷 754-761页

作者： Fawad Zaman Ijaz mansoor qureshi fahad munir Zafar Ullah Khan Department of Electronic Engineering Faculty of Engineering and Technology International Islamic University Sector H-10 Department of Electrical Engineering Air University

This paper proposes an efficient approach for four-dimensional （4D） parameter estimation of plane waves impinging on a 2-L shape array. The 4D parameters include amplitude, frequency and the two-dimensional （2D） direction of arrival, namely, azimuth and elevation angles. The proposed approach is based on memetic computation, in which the global optimizer, particle swarm optimization is hybridized with a rapid local search technique, pattern search. For this purpose, a new multi-objective fitness function is used. This fitness function is the combination of mean square error and the correlation between the normalized desired and estimated vectors. The proposed hybrid scheme is not only compared with individual performances of particle swarm optimization and pattern search, but also with the performance of the hybrid genetic algorithm and that of the traditional approach. A large number of monte-Carlo simulations are carried out to validate the performance of the proposed scheme. It gives promising results in terms of estimation accuracy, convergence rate, proximity effect and robustness against noise.

关键词： amplitude estimation direction of arrival estimation frequency estimation genetic algorithm

On ev and ve-Degree Based Topological Indices of Silicon Carbides

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Computer modeling in Engineering & Sciences 2022年第2期130卷 871-885页

作者： Jung Rye Lee Aftab Hussain Asfand fahad Ali Raza muhammad Imran qureshi Abid mahboob Choonkil Park Department of Data Science Daejin UniversityKyunggi11159Korea Department of mathematics King Abdulaziz UniversityJeddah21589Saudi Arabia Department of mathematics COMSATS University IslamabadVehari61110Pakistan Department of mathematics Division of Science&TechnologyUniversity of EducationLahorePakistan Research Institute for Natural Sciences Hanyang UniversitySeoul04763Korea

In quantitative structure-property relationship(QSPR)and quantitative structure-activity relationship(QSAR)studies,computation of topological indices is a vital tool to predict biochemical and physio-chemical properties of chemical *** topological indices have been inaugurated to describe different topological *** ev and ve-degree are recently introduced novelties,having stronger prediction *** this article,we derive formulae of the ev-degree and ve-degree based topological indices for chemical structure of Si_(2)C_(3)−I[a,b].

关键词： Topological indices silicon carbide ev-degree ve-degree

Interplay of parallel electric field and trapped electrons in kappa-maxwellian auroral plasma for EmEC instability

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Communications in Theoretical Physics 2021年第1期73卷 78-86页

作者： m Nazeer m N S qureshi C Shen Department of Physics GC UniversityLahore(54000)Pakistan Shenzhen Graduate School HIT CampusUniversity Town of ShenzhenShenzhen 518055China

In this paper,propagation characteristics of electromagnetic electron cyclotron(EmEC)waves based on kappa-maxwellian distribution have been investigated to invoke the interplay of the electric field parallel to the Earth’s magnetic field and auroral trapped *** dispersion relation for EmEC waves in kappa-maxwellian distributed plasma has been derived using the contribution of the parallel electric field and trapped electron *** results show that the presence of the electric field has a stimulating effect on growth rate,which is more pronounced at low values of wave *** is also observed that as the threshold value of trapped electron speed is surpassed,it dominates the effect of the parallel electric field and EmEC instability is enhanced *** electric field acts as another source of free energy,and growth can be obtained even in the absence of trapped electron drift speed and for very small values of temperature *** the present study reveals the interplay of the parallel electric field and trapped electron speed on the excitation of EmEC waves in the auroral region.

关键词： EmEC waves kappa-maxwellian distribution trapped electrons parallel electric field in aurora

Triangular code:Near-optimal linear time fountain code

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Digital Communications and Networks 2023年第4期9卷 869-878页

作者： Jalaluddin qureshi Chuan Heng Foh Openbet North America MontrealCanada GIC&6GIC Institute for Communication Systems(ICS)University of SurreyGuildfordUnited Kingdom

In this paper,we propose Triangular Code(TC),a new class of fountain code with near-zero redundancy and linear encoding and decoding computational complexities of OeLklog kT,where k is the packet batch size and L is the packet data *** from previous works where the optimal performance of codes has been shown under asymptotic assumption,TC enjoys near-zero redundancy even under non-asymptotic settings for smallmoderate number of *** features make TC suitable for practical implementation in batteryconstrained devices in IoT,D2D and m2m network paradigms to achieve scalable reliability,and minimize latency due to its low decoding *** is a non-linear code,which is encoded using the simple shift and XOR addition operations,and decoded using the simple back-substitution *** it is nonlinear code at the packet level,it remains linear code when atomized at the bit *** use this property to show that the backsubstitution decoder of TC is equivalent to the Belief Propagation(BP)decoder of LT ***,TC can benefit from rich prolific literature published on LT code,to design efficient code for various *** the equivalency between the decoders of TC and LT code,we show that compared to state-of-the-art optimized LT code,TC reduces the redundancy of LT code by 68%-99% for k reaching 1024.

关键词： LT code Decoder Computational complexity Green computing Network coding

Resolution of an esophageal leak and posterior gastric wall necrosis with esophageal self-expandable metal stents

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World Journal of Gastroenterology 2013年第40期19卷 6931-6933页

作者： majid A Almadi Abdulrahman m Aljebreen fahad Bamihriz Division of Gastroenterology King Khalid University Hospital King Saud University Riyadh 11461Saudi Arabia Division of Gastroenterology The McGill University Health Center montreal General Hospital McGill UniversityMontrealH3G 1A4Canada Division of Surgery King Khalid University HospitalKing Saud UniversityRiyadh 11461Saudi Arabia

The use of weight reduction surgeries has increased over the years with a higher proportion of these surgeries being sleeve gastrectomies,this has been associated with some complications including staple line *** report a 32-year-old male who had undergone a laparoscopic gastric band surgery and subsequently a laparoscopic sleeve gastrectomy,this was complicated by both an staple line leak at the gastroesophageal junction as well as a large(> 4 cm) posterior gastric wall defect due to gastric wall necrosis. We used two co-axially inserted self-expandable stents(SEmS) in the management of this patient,5 stents were used over repeated endoscopy sessions and 20 wk. Both defects had resolved without the need for surgical *** is the first reported case were SEmS are used for both a staple line leak as well as a gastric wall *** also review the literature on the use of SEmS in the management of leaks post weight reduction surgeries.

关键词： Stents Self-expandable metal stents Laparoscopic sleeve gastrectomy Staple line leak Esophageal leak Gastric necrosis

Temporal Correlation-Based Spatial Filtering of Rician Noise for Functional mRIs

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Chinese Physics Letters 2012年第1期29卷 287-290页

作者： Amir.A.Khaliq I.m.qureshi Jawad.A.Shah Department of Electronic Engineering International Islamic UniversityIslamabadPakistan Air University ISSSIslamabadPakistan

A novel correlation-based filter is presented for de-noising functional magnetic resonance imaging (fmRI) *** correlation-based exponential weights are defined for spatial smoothing of the data,with bias reduction using estimated noise *** proposed scheme is tested on simulated and real fmRI ***,the results are compared with conventional *** method is found to be effectively suppressing the Rician noise in fmRI data,while improving the SNR.

关键词： weights smoothing Spatial

Hydromagnetic peristaltic transport of copper-water nanofluid with temperature-dependent effective viscosity

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Particuology 2016年第4期14卷 133-140页

作者： fahad m. Abbasi Tasawar Hayat Sabir A. Shehzad Fuad Alsaadi Naif Altoaibi Department of mathematics COMSATS Institute of lnformation Technology Islamabad 44000 Pakistan Department of mathematics Quaid-l-Azam University 45320 Islamabad 44000 Pakistan Department of Electrical and Computer Engineering Faculty of Engineering King Abdulaziz University Jeddah Saudi Arabia Department of mathematics COMSATS Institute of Information Technology Sahiwal Pakistan

The unique chemical mechanical, and thermodynamic properties of nanofluids make them a subject of great interest for scientists from all domains. Such fluids are of particular significance in biomedical engineering owing to their vast and novel applications in modern drug delivery systems; for example, mixed convective peristaltic flow of water-based nanofluids under the influence of an externally applied magnetic field is of particular significance. Hence, a lot of research has focused on peristalsis in the presence of velocity and thermal slip effects. An empirical relation for the effective viscosity of the nanofluid is proposed here for the first time. The viscosity of the nanofluid varies with temperature and nanoparticle volume fraction. Numerical simulation of the resulting nonlinear system of equations is presented for different quantities of interest. The results indicate that the maximum velocity and temperature of the copper-water nanofluid increase for larger variable viscosity parameter. The pressure gradient in the wider part of the channel is also found to increase as a function of the variable viscosity parameter. The variable viscosity parameter also influences the size of the trapped bolus. An increase in the nanoparticle volume fraction reduces the reflux phenomenon in a peristaltic flow.

关键词： Temperature dependent effective viscosity Copper-water nanofluid Peristalsis Slip effect magnetohydrodynamics

Dust-Lower-Hybrid Surface Waves in Classical and Degenerate Plasmas

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Communications in Theoretical Physics 2013年第11期60卷 623-629页

作者： m.Ayub H.A.Shah m.N.S.qureshi m.Salimullah Department of Physics G. C. University Department of Physics Mirpur University of Science and Technology (MUST) Department of Physics Jahangirnagar University

The dispersion relation for general dust low frequency electrostatic surface waves propagating on an interface between a magnetized dusty plasma region and a vacuum is derived by using specular reflection boundary conditions both in classical and quantum regimes. The frequency limit ω ≤ωei ≤ ωce is considered and the dispersion relation for the Dust-Lower-Hybrid Surface Waves （DLHSW＇s） is derived for both classical and quantum plasma half-space and analyzed numerically. It is shown that the wave behavior changes as the quantum nature of the problem is considered.

关键词： dusty plasma lower hybird surface wave degenerate plasma

Zonal distribution and population biology of Ilyoplax frater (Brachyura:Ocypodoidea:Dotillidae) in a coastal mudflat of Pakistan

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Current Zoology 2010年第2期56卷 244-251页

作者： Noor Us SAHER Naureen Aziz qureshi Centre of Excellence in marine Biology University of Karachi Department of Fisheries and Aquaculture University of Veterinary and Animal Sciences

Zonal distribution and population biology of llyoplaxfrater were studied in a mangrove mudflat area of Pakistan. The crabs were collected from Korangi creek through transect and quadrat method from low tide level to high tide level. Two transects were delimited in a mangrove area of Korangi creek （24°79′N/67°20′E）. On each transect, three 0.25 m quadrats were sampled at three tidal levels on a monthly basis during low tide periods from march 2001 to February 2002. A total of 1124 crabs were obtained, of which 482 were males and 642 were females. Density of crabs varied between 0 and 90/m^2. The density and size distribution varied and showed significant differences from low to high tide level, and were positively correlated with the percent moisture, percent organic matter and sediment grain size. The carapace width （CW） ranged from 2.5 to 11.5 mm for male and 2.5 to 11.0 mm for female and was not significantly different. The overall sex ratio did not differ significantly from the expected 1：1 throughout the year in small crabs but was significantly different in adult crabs （Z2 = 49.73） with more male crabs, Size frequency distribution showed recruitment of juvenile crabs （〈 4 mm） nearly throughout the year except during June and July. Presence of ovigerous females in all months with seasonal peaks in September, October, December and may indicates seasonal continuous breeding. Weight of egg mass increases with weight of ovigerous females and show positive linear relationship. The estimated mean diameter of egg was 2.83±0.25μm, and the average number of eggs was 3065±902.

关键词： Ilyoplaxfrater Population biology Zonal distribution Sex ratio Fecundity Korangi creek Pakistan