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Exact solution to peristaltic transport of power-law fluid in asymmetric channel with compliant walls

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Applied Mathematics and Mechanics(English Edition) 2010年第10期31卷 1231-1240页

作者： T.HAYAT M.javed Department of Mathematics Quaid-i-Azam University Department of Mathematics College of SciencesKing Saud University

Effects of compliant wall properties on the peristaltic flow of a non-Newtonian fluid in an asymmetric channel are *** rheological characteristics are characterized by the constitutive equations of a power-law *** wavelength and low Reynolds number approximations are adopted in the presentation of mathematical *** solutions are established for the stream function and *** streamlines pattern and trapping are given due *** features of the key parameters entering into the present flow are displayed and important conclusions are pointed out.

关键词： peristaltic flow power-law fluid compliant walls

Landslide susceptibility analysis of Karakoram highway using analytical hierarchy process and scoops 3D

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Journal of Mountain Science 2020年第7期17卷 1596-1612页

作者： Barira RASHID javed IQBAL SU Li-jun Institute of Geographical Information Systems School of Civil&Environmental EngineeringNational University of Sciences and Technology(NUST)Islamabad44000Pakistan Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu610041China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing100101China University of Chinese Academy of Sciences Beijing100049China

Landslides are prevalent,regular,and expensive hazards in the Karakoram Highway(KKH)*** KKH connects Pakistan with China in the present China-Pakistan Economic Corridor(CPEC)*** region has not only immense economic importance but also ecological *** purpose of the study was to map the landslide-prone areas along KKH using two different techniquesAnalytical Hierarchy Process(AHP)and Scoops 3 D *** causative parameters for running AHP include the lithology,presence of thrust,land use land cover,precipitation,and Digital Elevation Model(DEM)derived variables(slope,curvature,aspect,and elevation).The AHP derived final landslide susceptibility map was classified into four zones,i.e.,low,moderate,high,and extremely *** 80%of the study area falls under the moderate(43%)and high(40%)landslide susceptible *** assess the slope stability of the study area,the Scoops 3 D model was used by integrating with the earthquake loading *** results of the limit equilibrium analysis categorized the area into four groups(low,moderate,high,and extremely high mass)of slope *** areas around Main Mantle Thrust(MMT)including Dubair,Jijal,and Kohistan regions,had high volumes of potential slope *** results from AHP and Scoops 3 D techniques were validated with the landslides inventory record of the Geological Survey of Pakistan and Google *** results from both the techniques showed similar output that coincides with the known landslides ***,Scoops 3 D provides not only susceptible zones but also the range of volume of the potential slope ***,these techniques could be used in other mountainous areas,which could help in the landslide mitigation measures.

关键词： Landslide mapping Landslide hazard zonation Analytical Hierarchy Process(AHP) Scoops 3D China Pakistan Economic Corridor(CPEC) Karakoram Highway

Friction assisted solid state lap seam welding and additive manufacturing method

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Defence Technology（防务技术） 2016年第1期12卷 16-24页

作者： Prasad Rao KALVALA javed AKRAM Mano MISRA Dept. of Metallurgical Engineering University of Utah

This paper describes results of seam welding of relatively high temperature melting materials, AISI 304, C-Mn steels, Ni-based alloys, CP Cu, CP Ni, Ti6Al4V and relatively low temperature melting material, AA6061. It describes the seam welding of multi-layered similar and dissimilar metallic sheets. The method described and involved advancing a rotating non-consumable rod(CP Mo or AISI 304) toward the upper sheet of a metallic stack clamped under pressure. As soon as the distal end of the rod touched the top portion of the upper metallic sheet, an axial force was applied. After an initial dwell time, the metallic stack moved horizontally relative to the stationery non-consumable rod by a desired length, thereby forming a metallurgical bond between the metallic sheets. Multi-track and multi-metal seam welds of high temperature metallic sheets, AISI 304, C-Mn steel,Nickel-based alloys, Cp Cu, Ti6Al4V and low temperature metallic sheets, AA6061 were obtained. Optical and scanning electron microscopy examination and 180 degree U-bend test indicated that defect free seam welds could be obtained with this method. Tensile- shear testing showed that the seam welds of AISI 304, C-Mn steel, Nickel-based alloy were stronger than the starting base metal counterparts while AA6061 was weaker due to softening. The metallurgical bonding at the interface between the metallic sheets was attributed to localized stick and slip at the interface, dynamic recrystallization and diffusion. The method developed can be used as a means of welding, cladding and additive manufacturing.

关键词： Lap seam welding Friction assisted welding Solid-state welding Cladding Additive manufacturing

Frequency hopping in IEEE 802.15.4 to mitigate IEEE 802.11 interference and fading

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Journal of Systems Engineering and Electronics 2018年第3期29卷 445-455页

作者： javed Umer HE Di LIU Peilin YANG Yueming Shanghai Key Laboratory of Navigation and Location-based Services Shanghai Jiao Tong University Shanghai Panchip Microelectronics Co. Ltd

In this paper, we investigate the issues of initialization and deployment of wireless sensor networks（WSNs） under IEEE 802.11 b/g interference and fading channels using frequency hopping（FH）. We propose an FH algorithm for WSNs, which is implemented and tested with a pair of nodes employing IPv6 over low power wireless personal area networks（6 LoWPAN） *** merits and demerits of the proposed FH scheme in WSNs are studied under strong IEEE 802.11 b/g interference and frequency selective fading channels. We compare the performance results of the proposed FH scheme with those obtained by single-channel radio in WSNs, and show that FH maintains very reliable data rates in the presence of adverse conditions where the single-channel radio fails. We determine a minimum center frequency offset of channels between IEEE 802.15.4 and IEEE 802.11 b/g-based networks, which guarantees the error free network operation of IEEE802.15.4 using a single channel. We design a second FH procedure comprising only four free channels（15, 20, 25, and 26） of IEEE 802.15.4 standard, and show that in the presence of nearby IEEE 802.11 b/g interference, the IEEE 802.15.4 data rate using this method is always 98% and more.

关键词： IEEE 802.15.4 wireless sensor networks(WSNs) frequency hopping(FH) interference avoidance coexistence

Helicobacter pylori infection and micronutrient deficiencies

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World Journal of Gastroenterology 2003年第10期9卷 2137-2139页

作者： javed Yakoob Wasim Jafri Shahab Abid Section of Gastroenterology Department of MedicineAga Khan University HospitalStadium RoadKarachiPakistan

It is known that deficiencies of micronutrients due to infections increase morbidity and *** phenomenon depicts itself conspicuously in developing countries. Deficiencies of iron,vitamins A,E,C,B12,etc are widely prevalent among populations living in the third world *** pylori(H pylori)infection has a high prevalence throughout the *** of several micronutrients due to H pylori infection may be concomitantly present and vary from subtle sub-clinical states to severe clinical *** essential trace elements/ micronutrients are involved in host defense mechanisms, maintaining epithelial cell integrity,glycoprotein synthesis, transport mechanisms,myocardial contractility,brain development,cholesterol and glucose *** this paper H pylori infection in associaed with various micronutrients deficiencies is briefly reviewed.

关键词： Helicobacter pylori Avitaminosis Helicobacter Infections Humans Micronutrients

Some Homological Characterizations of Semigroups and Semirings

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Acta Mathematica Sinica,English Series 2011年第10期27卷 2065-2072页

作者： javed AHSAN Zhong Kui LIU Muhammad SHABIR Department of Mathematics International Islamic University H-10 CampusIslamabad 44000 Pakistan Department of Mathematics Northwest Normal University Lanzhou 730070 P. R. China Department of Mathematics Quaid-i-Azam University Islamabad 44000 Pakistan

In this paper we characterize semirings all of whose p-injective semimodules are injective. We also classify monoids all of whose p-injective acts are injective.

关键词： P-injective semimodule injective semimodule p-injective act injective act

Biosorption characteristics of unicellular green alga Chlorella sorokiniana immobilized in loofa sponge for removal of Cr(Ⅲ)

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Journal of Environmental Sciences 2008年第2期20卷 231-239页

作者： AKHTAR Nasreen IQBAL Muhammad ZAFAR Saeed Iqbal IQBAL javed Department of Biology Government lslamia College for WomenCooper RoadLahore-54550Pakistan. Environment Biotechnology Group Biotechnology and Food Research CentrePCSIR Laboratories ComplexLahore-54600Pakistan. School of Biological Sciences University of PunjabLahore-54570Pakistan.

Loofa sponge （LS） immobilized biomass of Chlorella sorokiniana （LSIBCS）, isolated from industrial wastewater, was investigated as a new biosorbent for the removal of Cr（Ⅲ） from aqueous solution. A comparison of the biosorption of Cr（Ⅲ） by LSIBCS and free biomass of C. sorokiniana （FBCS） from 10-300 mg Cr（Ⅲ）/L aqueous solutions showed an increase in uptake of 17.79% when the microalgal biomass was immobilized onto loofa sponge. Maximum biosorption capacity for LSIBCS and FBCS was found to be 69.26 and 58.80 mg Cr（Ⅲ）/g biosorbent, respectively, whereas the amount of Cr（Ⅲ） ions adsorbed onto naked LS was 4.97 mg/g. The kinetics of Cr（Ⅲ） biosorption was extremely rapid and equilibrium was established in about 15 and 20 min by LSIBCS and FBCS, respectively. The biosorption equilibrium was well defined by Langmuir adsorption isotherm model. The biosorption kinetics followed the pseudo-second order kinetic model. The biosorption was found to be pH dependent and the maximum sorption occurred at the solution pH 4.0. Desorption studies showed that 98% of the adsorbed Cr（Ⅲ） could be desorbed with 0.1 mol/L HNO3, while other desorbing agents were less effective in the order： EDTA 〉 H2SO4 〉 CH3COOH 〉 HCl. The regenerated LSIBCS retained 92.68% of the initial Cr（Ⅲ） binding capacity up to five cycles of reuse in continuous flow-fixed bed columns. The study revealed that LSIBCS could be used as an effective biosorbent for the removal of Cr（Ⅲ） from wastewater.

关键词： biosorption immobilization loofa sponge Chlorella sorokiniana Cr(Ⅲ) desorption fixed bed column reactor

Control Algorithm Based on Limit Cycle Oscillator-FLL for UPQC-S with Optimized PI Gains

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 649-661页

作者： Sabha Raj Arya Sayed javed Alam Papia Ray Department of Electrical Engineering Sardar Vallabhai National Institute of TechnologySuart-395007(Gujarat)gIndia Department of Electrical Engineering Veer Surendra Sai University of Technology(Government University)BurlaSambalpurIndia

This paper involves a limit cycle oscillator-frequency lock loop(LCO-FLL)based control algorithm for unified power quality controllers-S type(UPQC-S)for compensation of reactive power,to maintain a unity power factor,regulate constant voltage at the PCC,mitigate sag,swell and to eliminate *** this approach,an extraction of fundamental in-phase and quadrature components for the estimation of reference signals are taken from the LCO-FLL *** control LCO-FLL provides a high grade of protection against sag-swell voltages,unbalance loading and harmonics present in the utility *** addition to that,it has advantageous characteristics of synchronization with the grid frequency at any previously mentioned conditions without use of phase locked loops or trigonometric *** advantages of the LCO-FLL are to give useful information to estimate fundamental components from a highly polluted grid *** values obtained from the JAYA optimization algorithm are used to fine-tune the proportional integral(PI)controller gains,so that it maintains DC link voltage to the desired *** mean square error(MSE)is employed as an objective function for optimizing the error between actual and reference *** control algorithm based on LCO-FLL is developed in MATLAB/Simulink software and it is tested for power conditioning features.

关键词： JAYA MSE LCO-FLL PI Tuning Sag unbalanced VSC

Evaluating location specific strain rates, temperatures,and accumulated strains in friction welds through microstructure modeling

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Defence Technology（防务技术） 2018年第2期14卷 83-92页

作者： javed Akram Prasad Rao Kalvala Vikas Jindal Mano Misra Dept. of Metallurgical Engineering University of Utah Dept. of Metallurgical Engineering Indian Institute of Technology(BHU)

A microstructural simulation method is adopted to predict the location specific strain rates, temperatures, grain evolution, and accumulated strains in the Inconel 718 friction welds. Cellular automata based 2D microstructure model was developed for Inconel 718 alloy using theoretical aspects of dynamic recrystallization. Flow curves were simulated and compared with experimental results using hot deformation parameter obtained from literature work. Using validated model, simulations were performed for friction welds of Inconel 718 alloy generated at three rotational speed i.e., 1200, 1500, and1500 RPM. Results showed the increase in strain rates with increasing rotational speed. These simulated strain rates were found to match with the analytical results. Temperature difference of 150 K was noticed from center to edge of the weld. At all the rotational speeds, the temperature was identical implying steady state temperature(0.89 T_m) attainment.

关键词： Microstructure modeling Dynamic recrystallization Friction welding Inconel 718 EBSD Hot deformation Strain map