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Digital Communications and Networks 2017年第3期3卷 150-163页

作者： syed rehan afzal Sander Stuijk Majid Nabi Twan Basten Eindhoven University of Technology Den Dolech 2 5612AZ Eindhoven The Netherlands TNO-ESI Embedded Systems Innovation De Rondom 1 5612AP Eindhoven The Netherlands

Accurate link quality estimation is a fundamental building block in quality aware multi hop routing. In an inherently lossy, unreliable and dynamic medium such as wireless, the task of accurate estimation becomes very challenging. Over the years ETX has been widely used as a reliable link quality estimation metric. However, more recently it has been established that under heavy traffic loads ETX performance gets significantly worse. We examine the ETX metric＇s behavior in detail with respect to the MAC layer and UDP data; and identify the causes of its unreliability. Motivated by the observations made in our analysis, we present the design and implementation of our link quality measurement metric xDDR - a variation of ETX. This article extends xDDR to support network mobility. Our experiments show that xDDR substantially outperforms minimum hop count, ETX and HETX in terms of end-to-end packet delivery ratio in static as well as mobile scenarios.

关键词： Asymmetric link quality Link-quality measurement Wireless ad hoe networks

A Scalable Key Management Scheme for Secure Multicasting over Bluetooth Scatternets

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China Communications 2008年第2期5卷 25-33页

作者： Subir Biswas syed rehan afzal Jong-bin Koh Mustafa Hasan Gunhee Lee Dong-kyoo Kim Graduate School of Information and Communication Ajou University

Secure multicasting is one of the major requirementsfor today’s communication *** for any kindof secure communication,a key-distribution schemeis the most sensible *** a highly promising,low-cost,and emerging wireless technology,Bluetooth has key distribution supports for securemulticasting over its unit one-hop network,*** core specification[1]defines basic securityprotocols for key generation,encryption,andauthentication for intra-piconet ***,not much attention has been paid so far on securingmulticasting over the Bluetooth Scatternet;nevertheless,multicasting is quite a sensible aspectof modern communication *** in this paper,we extend the piconets key distribution scheme topresent a new key management scheme for securemulticasting over Bluetooth *** keymanagement scheme is compatible to the currentBluetooth architecture design as we rely onBluetooth’s existing security algorithms to proposeour resolution.

关键词： Bluetooth Piconet Scattemet Master node Master key

Tween 80 containing lipid nanoemulsions for delivery of indinavir to brain

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Acta Pharmaceutica Sinica B 2013年第5期3卷 345-353页

作者： Kandadi Prabhakar syed Muzammil afzal Goparaboina Surender Veerabrahma Kishan Nanotechnology Laboratory Department of PharmaceuticsUniversity College of Pharmaceutical SciencesKakatiya UniversityWarangal 506009India

Indinavir is a protease inhibitor used in the treatment of HIV ***,it has limited efficacy in eradicating the virus in the brain due to efflux by P-glycoprotein(P-gp)expressed at the blood–brain barrier(BBB).The objective of this work was to develop an o/w lipid nanoemulsion(LNE)of indinavir using Tween 80 as co-emulsifier to improve its brain specific *** were prepared with different compositions and were characterized for globule size,polydispersity index,zeta potential and in vitro drug *** formulations were then evaluated for drug content,entrapment efficiency and stability after which brain uptake studies were carried out using fluorescent labeled LNEs and pharmacokinetic(PK)and tissue distribution studies were conducted after intravenous administration in *** uptake of indinavir was shown to be improved for a 1%Tween 80 containing formulation(F5)compared to a formulation containing 0.3%cholesterol(F2).In PK studies,the brain level of indinavir subsequent to administration of F5 was significantly(Po0.05)higher than produced by administration of a drug solution(2.44-fold)or a control nanoemulsion(F1)(1.48-fold)or formulation F2(1.6-fold).The increased brain specific accumulation of indinavir from F5 is probably due to enhanced low density lipoprotein-mediated endocytosis and P-gp inhibition by Tween 80 at the *** results suggest Tween 80 containing LNEs could provide a simple but effective means of delivering indinavir to brain.

关键词： Tween 80 Indinavir Lipid nanoemulsions Brain delivery Therapeutic availability Fluorescent DiD oil

Human Behavior Classification Using Geometrical Features of Skeleton and Support Vector Machines

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Computers, Materials & Continua 2019年第8期61卷 535-553页

作者： syed Muhammad Saqlain Shah Tahir afzal Malik Robina khatoon syedSaqlain Hassan Faiz Ali Shah Department of CS&SE International Islamic UniversityH-10 SectorIslamabad44000Pakistan Department of Management Information Systems Ibn Rushd College of Management SciencesAbhaSaudi Arabia Department of Computer Science Bahria UniversityIslamabad44000Pakistan Institute of Computer Science University of TartuTartuEstonia

Classification of human actions under video surveillance is gaining a lot of attention from computer vision *** this paper,we have presented methodology to recognize human behavior in thin crowd which may be very helpful in *** have mostly focused the problem of human detection in thin crowd,overall behavior of the crowd and actions of individuals in video *** based Human behavior modeling is a complex task as it involves human detection,tracking,classifying normal and abnormal *** proposed methodology takes input video and applies Gaussian based segmentation technique followed by post processing through presenting hole filling algorithm i.e.,fill hole inside objects *** detection is performed by presenting human detection algorithm and then geometrical features from human skeleton are extracted using feature extraction *** classification task is achieved using binary and multi class support vector *** proposed technique is validated through accuracy,precision,recall and F-measure metrics.

关键词： Human behavior classification segmentation human detection support vector machine

Suitability of marble powders in production of high strength concrete

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Low-carbon Materials and Green Construction 2023年第1期1卷 365-380页

作者： syed afzal Basha Faiz Uddin Ahmed Shaikh G Pullaiah College of Engineering and Technology KurnoolAndhra PradeshIndia School of Civil and Mechanical Engineering Curtin UniversityPerthAustralia

A tremendous amount of non-biodegradable waste is created during mining and processing tasks of layered stones like *** time,this has become a global problem because it harms the environment in multiple ***,it is necessary to find an alternate way to securely dispose and reuse marble *** construction sector is one of the significant consumers of natural resources for the production of material binders and *** a result,in recent years,number of researchers have carried out studies in which various kinds of marble waste have been incorporated into concrete with the intention of substituting either cement or aggregates or *** paper presents the effect of two locally sourced waste marble powders Kadapa marble powder(KMP)and Bethamcherla marble powder(BMP)as partial replacement of cement on mechanical and durability properties of high strength concrete(HSC).Their effect at different replacement levels in HSC is evaluated in compressive,indirect tensile and flexural strengths,elastic modulus,chloride penetration resistance and freeze-thaw durability ***-structural investigation is also conducted to evaluate their impact on the matrix of HSC containing waste marble powders as additional cementitious *** show that the HSC consisting of KMP and BMP content of 10%and 15%,respectively exhibited higher mechanical and durability properties than the control ***-structural investigation also supports this *** can be concluded that the use of marble powders as partial replacement of cement does not have any adverse impact on the properties of *** use of KMP and BMP reduces the vast amount of energy required to produce cement,cost and time with reduction in environmental hazards.

关键词： Bethamcherla marble powder High strength concrete Kadapa marble powder Manufactured sand

Application of Electrodynamic Theory on Quantum Hall Effect

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World Journal of Condensed Matter Physics 2016年第2期6卷 87-94页

作者： Saleem Iqbal Muhammad Zafar Farhana Sarwar syed Mohsin Raza Muhammad afzal Rana Department of Mathematics University of Balochistan Quetta Pakistan Department of Basic Sciences Riphah International University Islamabad Pakistan Department of Mathematics F. G. Girls Degree College Quetta Pakistan Department of Physics University of Balochistan Quetta Pakistan

The quantum electrodynamic (QED) behaviour is studied for quantum Hall effect (QHE). Quantum theory with conjecture of fractional charge quantization (quantum dipole moment), eigenfunctions for fractional charge quantization at the surface of a twisted and twigged electron quanta and above its surface, fractional Fourier transform and Hermite function for fractional charge quantization is developed. With energy eigen value equation for QHE and with energy operator on an eigenfunction of a twisted and twigged electron quanta, the corresponding eigenfunctions are normalized with Schrodinger’s quantum wave mechanical equation for electric scalar and magnetic potentials, respectively (QED behavior). The fractional electric and magnetic fields with their corresponding potentials for the quantized fractional states in semiconducting hereto structures are theoretically calculated. Such mathematical expressions are in good agreement with experimental results of Nobel Prize winning scientists Klitzing, Haroche, Peter and Gruebber. Our results can also explain the hybridized states of orbits with emphasis on sigma and pi bonding and their corresponding antibonding orbitals as a manifestation of electrophilic and nucleophilic chemical reactions.

关键词： Fractional Charge Quantization Fractional Fourier Transform Quantum Hall Effect Quantum Electrodynamics Electron Quanta String Twisted and Twigged Electron Quanta

Prevalence and gene frequency of color vision impairments among children of six populations from North Indian region

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Genes & Diseases 2015年第2期2卷 211-218页

作者： Mohd Fareed Malik Azeem Anwar Mohammad afzal Human Genetics and Toxicology Laboratory Section of GeneticsDepartment of ZoologyFaculty of Life SciencesAligarh Muslim UniversityAligarh202002Uttar PradeshIndia Department of Molecular Genetics The Ohio State UniversityColumbusOHUSA

X-linked redegreen color blindness is the most widespread form of vision *** study aimed to determine the prevalence and gene frequencies of redegreen color vision impairments among children of six different human populations of Jammu province.A total of 1028 healthy subjects(6e15 years of age)were selected from five Muslim populations and the color vision impairments were determined using the Ishihara’s test of color *** gene frequency was calculated using HardyeWeinberg equilibrium *** prevalence of color vision deficiency(CVD)ranged from 5.26%to 11.36%among males and 0.00%e3.03%among females of six different *** gender based differences in the frequency of CVD was found to be statistically significant(psyed population while the frequencies of protanomaly(1.94%),protanopia(1.28%)and achromacy(2.27%)were the highest among male subjects of Khan,Malik and syed populations,*** allele and genotype frequencies showed cogent differences among six *** population based assessment of CVDs help patients to follow adaptive strategies that could minimize the risks of the disease.

关键词： Allele frequency Color blindness Color vision deficiency Gene frequency Genotypes Human populations Public health Vision science