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Exogenously applied glycinebetaine induced alteration in some key physio-biochemical attributes and plant anatomical features in water stressed oat(Avena sativa L.) plants

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Journal of Arid Land 2019年第2期11卷 292-305页

作者： Anum SHEHZADI Nudrat A AKRAM Ayaz ALI Muhammad ashraf Department of Botany Government College University Pakistan Science Foundation Department of Botany King Saud University

Although exogenous application of glycinebetaine(GB) is widely reported to regulate a myriad of physio-biochemical attributes in plants under stressful environments including drought stress, there is little information available in the literature on how and up to what extent GB can induce changes in anatomical features in water starved plants. Thus, the present research work was conducted to assess the GB-induced changes in growth, physio-biochemical, and anatomical characteristics in two cultivars(CK-1 and F-411) of oat(Avena sativa L.) under limited water supply. After exposure to water stress, a considerable reduction was observed in plant growth in terms of lengths and weights of shoot and roots,leaf mesophyll thickness, leaf midrib thickness, root cortex thickness, root diameter, stem diameter, stem phloem area, and stem vascular bundle area in both oat cultivars. However, water stress resulted in a significant increase in leaf total phenolics, hydrogen peroxide(H_2 O_2), ascorbic acid(AsA), GB contents,activities of enzymes(CAT, SOD and POD), total soluble proteins, leaf epidermis(abaxial and adaxial)thickness, bulliform cell area, sclerenchyma thickness, root endodermis and epidermis thickness, root metaxylem area, stem metaxylem area and stem sclerenchyma thickness in both oat ***-applied 100 mM GB suppressed H_2 O_2 contents, while improved growth attributes, free proline and GB contents, activity of SOD enzyme, leaf abaxial epidermis thickness, leaf bulliform cell area, leaf midrib thickness, leaf sclerenchyma thickness, root cortex thickness, root endodermis, epidermis thickness,root stele diameter, stem diameter, stem epidermis thickness, stem metaxylem area, and stem phloem and vascular bundle area in both oat cultivars. For both oat cultivars, CK-1 was superior to F-411 in leaf abaxial epidermis thickness, leaf mesophyll, leaf sclerenchyma, root metaxylem area, stem diameter, stem epidermis, sclerenchyma thickness, stem metaxylem area, and

关键词： drought tolerance anatomical features oat glycinebetaine antioxidants

Modular Multilevel Converter with Wireless Magnetic Power Decoupling for Three-phase MV Adjustable-speed Drives

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CSEE Journal of Power and Energy Systems 2022年第5期8卷 1497-1507页

作者： Mohamed Atef Tawfik Mohammad Sameer Irfan ashraf Ahmed Joung-Hu Park Department of Electrical Engineering Soongsil UniversitySeoul 156-743South Korea

In this paper,we propose a modular multilevel converter(MMC)with a wireless magnetic power decoupling approach suitable for medium-voltage high-power variable-speed machine *** proposed power decoupling approach is independent of the operating frequency,which solves the issue of wide fluctuations of low-frequency voltage ripple components in submodule(SM)capacitors,especially at low-speed operations without using any ripple power *** wireless magnetic elements reduces the amount of high-voltage insulation between the transformer windings,resulting in a significant reduction in the overall size of the *** basic idea of our proposed approach is to magnetically couple the instantaneous three-phase ripple power of each of the three adjacent-arm *** proposed MMC is free from low-frequency capacitors,resulting in enhanced system reliability,volume,and *** operation principles of the proposed MMC are explained,and a control design is *** performance of the proposed scheme was verified via simulation and experimental tests.

关键词： Modular multilevel converter power decoupling submodule capacitor voltage ripple variable-speed drives wireless high-frequency transformer

Wi-Fi Positioning Dataset with Multiusers and Multidevices Considering Spatio-Temporal Variations

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Computers, Materials & Continua 2022年第3期70卷 5213-5232页

作者： Imran ashraf Sadia Din Soojung Hur Yongwan Park Department of Information and Communication Engineering Yeungnam UniversityGyeongsan-si38541Korea

Precise information on indoor positioning provides a foundation for position-related customer *** the emergence of several indoor positioning technologies such as ultrawideband,infrared,radio frequency identification,Bluetooth beacons,pedestrian dead reckoning,and magnetic field,Wi-Fi is one of the most widely used ***,Wi-Fi fingerprinting is the most popular method and has been researched over the past two ***-Fi positioning faces three core problems:device heterogeneity,robustness to signal changes caused by human mobility,and device attitude,i.e.,varying *** existing methods do not cover these aspects owing to the unavailability of publicly available *** study introduces a dataset that includes the Wi-Fi received signal strength(RSS)gathered using four different devices,namely Samsung Galaxy S8,S9,A8,LG G6,and LG G7,operated by three surveyors,including a female and two *** addition,three orientations of the smartphones are used for the data collection and include multiple buildings with a multifloor *** levels of human mobility have been considered in dynamic *** analyze the time-related impact on Wi-Fi RSS,data over 3 years have been considered.

关键词： Wi-fi positioning dataset smartphone sensors benchmark analysis indoor positioning and localization spatio-temporal data

Synergy of remotely sensed data in spatiotemporal dynamic modeling of the crop and cover management factor

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Pedosphere 2022年第3期32卷 381-392页

作者： Pooja P.PREETHA ashraf Z.AL-HAMDAN Department of Civil Engineering Alabama A&M University4900 Meridian Street NHuntsvilleAL 35811-7500(USA) Department of Civil and Environmental Engineering University of Alabama in Huntsville301 Sparkman DriveHuntsvilleAL 35899-7500(USA)

Soil erosion is a threat to the water quality constituents of sediments and nutrients and can cause long-term environmental *** important parameter to quantify the risk of soil loss from erosion is the crop and cover management factor(C-factor),which represents how cropping and management practices affect the rates and potential risk of soil *** developed remotely sensed data-driven models for dynamic predictions of C-factor by implementing dynamic land cover modeling using the SWAT(Soil and Water Assessment Tool)model on a watershed *** remotely sensed processed variables included the enhanced vegetation index(EVI),the fraction of photosynthetically active radiation absorbed by green vegetation(FPAR),leaf area index(LAI),soil available water content(AWC),slope gradient(SG),and ratio of area(AR)of every hydrologic response unit(HRU)to that of the total watershed,comprising unique land cover,soil type,and slope gradient characteristics within the Fish River catchment in Alabama,USA between 2001 and *** regressions,spatial trend analysis,correlation matrices,forward stepwise multivariable regression(FSMR),and 2-fold cross-validation were conducted to evaluate whether there were possible associations between the C-factor and EVI with the successive addition of remotely sensed environmental *** on the data analysis and modeling,we found a significant association between the C-factor and EVI with the synergy of the environmental factors FPAR,LAI,AWC,AR,and SG(predicted R^(2)(R^(2)_(pred))=0.51;R^(2)=0.68,n=3220,P<0.15).The results showed that the developed FSMR model constituting the non-conventional factors AWC(R^(2)_(pred)=0.32;R^(2)=0.48,n=3220,P<0.05)and FPAR(R^(2)_(pred)=0.13;R^(2)=0.28,n=3220,P=0.31)was an improved fit for the watershed *** conclusion,the union of dynamic variables related to vegetation(EVI,FPAR,and LAI),soil(AWC),and topography(AR and SG)can be utilized for spatiotemporal C-factor estimation and to mo

关键词： C-factor enhanced vegetation index land cover modeling remote sensing soil erosion soil moisture solar radiation

Fuzzy Transitive Relations

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模糊系统与数学 2010年第4期24卷 162-169页

作者： Ismat Beg Samina ashraf Centre for Advanced Studies in Mathematics Lahore University of Management Sciences 54792-LahorePAKISTAN

A modified definition of fuzzy transitivity is *** properties of this new definition are *** of these new properties of transitivity on equivalence relations is also studied.

关键词： Fuzzy Relations Transitivity Order Equivalence Approximate Indistinguishability

Hyperspectral imaging and remote trace detection of cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHMX)compared with traditional explosives using laser induced fluorescence

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Defence Technology（防务技术） 2021年第5期17卷 1609-1616页

作者： Hany S.Ayoub ashraf F.El-Sherif Ahmed Elbeih Department of Physics Faculty of ScienceCairo UniversityEgypt Laser Photonics Research Center Engineering Physics DepartmentMilitary Technical CollegeCairoEgypt Explosives Department Military Technical CollegeKobry ElkobbahCairoEgypt

cis-1,3,4,6-Tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHMX)is an advanced energetic compound that expected to spread worldwide in the near ***,no approved remote detection methods were reported in current literature for this material,we performed hyper-spectral imaging and laser induced fluorescence(LIF)to a BCHMX sample under low laser fluence for determining the optimum laser wavelength used in any future BCHMX-LIF based remote detection *** this purpose,an experimental setup consisted of a sun spectrum lamp and hyper-spectral camera was built to illuminate and image white powder samples of BCHMX in comparison with the traditional explosives,HMX(1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane),RDX(1,3,5-trinitro-1,3,5-triazacyclohexane),PETN(2,2-Bis[(nitroxy)methyl]propane-1,3-diyldinitrate).The imaging reveals strong BCHMX sample absorption contrast among other samples at wavelength ranging from 400 to 410 *** light source was replaced by a 405 nm laser diode illuminator,a strong BCHMX sample LIF at the spectral range from 425 to 700 nm was observed under low laser fluence condition of 0.1 mJ/cm^(2).Finally,we demonstrated successfully the ability of the 405 nm LIF and the hyperspectral imaging technique to detect finger print traces of BCHMX on white cellulose fabric from a distance of 15 m and a detection limit of 1 mg/cm^(2).

关键词： Hyperspectral imaging Remote trace detection BCHMX Laser induced fluorescence

Numerical investigations of asymmetric flow of a micropolar fluid between two porous disks

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Acta Mechanica Sinica 2009年第6期25卷 787-794页

作者： Muhammad ashraf M.Anwar Kamal K.S.Syed Centre for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya University Multan Pakistan Department of Mathematics King Saud University RiyadhSaudi Arabia

Numerical solution is presented for the two- dimensional flow of a micropolar fluid between two porous coaxial disks of different permeability for a range of Reynolds number Re （-300≤ Re 〈 0） and permeability parameter A （1.0≤A ≤2.0）. The main flow is superimposed by the injection at the surfaces of the two disks. Von Karman＇s similarity transformations are used to reduce the governing equations of motion to a set of non-linear coupled ordinary differential equations （ODEs） in dimensionless form. An algorithm based on the finite difference method is employed to solve these ODEs and Richardson＇s extrapolation is used to obtain higher order accuracy. The results indicate that the parameters Re and A have a strong influence on the velocity and microrotation profiles, shear stresses at the disks and the position of the viscous/shear layer. The micropolar material constants cl, c2, c3 have profound effect on microrotation as compared to their effect on streamwise and axial velocity profiles. The results of micropolar fluids are compared with the results for Newtonian fluids.

关键词： Porous disks . Asymmetric flow .Micropolar fluid . Finite differences.Viscous layer

Robotic exoskeletons: The current pros and cons

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World Journal of Orthopedics 2018年第9期9卷 112-119页

作者： ashraf S Gorgey Spinal Cord Injury and Disorders Center Hunter Holmes McGuire VAMC Department of Physical Medicine and Rehabilitation Virginia Commonwealth University

Robotic exoskeletons have emerged as rehabilitation tool that may ameliorate several of the existing healthrelated consequences after spinal cord injury(SCI).However,evidence to support its clinical application is still lacking considering their prohibitive *** current mini-review is written to highlight the main limitations and potential benefits of using exoskeletons in the rehabilitation of persons with *** have recognized two main areas relevant to the design of exoskeletons and to their applications on major health consequences after *** design prospective refers to safety concerns,fitting time and speed of *** health prospective refers to factors similar to body weight,physical activity,pressure injuries and bone *** trials are currently underway to address some of these limitations and to maximize the benefits in rehabilitation *** directions highlight the need to use exoskeletons in conjunction with other existing and emerging technologies similar to functional electrical stimulation and brain-computer interface to address major *** have the potential to revolutionize rehabilitation following SCI;however,it is still premature to make solid recommendations about their clinical use after SCI.

关键词： Spinal cord injury Exoskeleton Robotics Rehabilitation Locomotion

Effect of chromium on growth attributes in sunflower(Helianthus annuus L.)

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Journal of Environmental Sciences 2008年第12期20卷 1475-1480页

作者： FOZIA Andaleeb MUHAMMAD Anjum Zia MUHAMMAD ashraf ZAFAR Mahmood Khalid National Institute for Biotechnology and Genetic Engineering Department of Chemistry and Biochemistry University of Agriculture Department of Botany University of Agriculture

Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the *** the present study,a pot experiment was conducted to evaluate the effect of chromium-contaminated soil in sunflower(Helianthus annuus L.)growth *** different levels of chromium(Cr)i.e.,20, 40,and 60 mg/kg were applied to three varieties of sunflower(G-3,G-9,and G-59).The results of morphological,chemical,and yield p...

关键词： Helianthus annuus L. soil chromium growth attributes