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An Improved Hybrid Indoor Positioning Algorithm via QPSO and MLP Signal Weighting

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Computers, Materials & Continua 2023年第1期74卷 379-397页

作者： Edgar Scavino Mohd Amiruddin abd Rahman Zahid Farid Department of Physics Faculty of ScienceUniversiti Putra MalaysiaUPM Serdang43400Malaysia Department of Electrical Engineering Abasyn UniversityKhyber-PakhtunkhwaPakistan

Accurate location or positioning of people and self-driven devices in large indoor environments has become an important necessity The application of increasingly automated self-operating moving transportation units,in large indoor spaces demands a precise knowledge of their *** like WiFi and Bluetooth,despite their low-cost and availability,are sensitive to signal noise and fading *** these reasons,a hybrid approach,which uses two different signal sources,has proven to be more resilient and accurate for the positioning determination in indoor ***,this paper proposes an improved hybrid technique to implement a fingerprinting based indoor positioning,using Received Signal Strength information from available Wireless Local Area Network access points,together with the Wireless Sensor Networks *** signals were recorded on a regular grid of anchor points,covering the research *** optimization was performed by relative signal weighting,to minimize the average positioning error over the research *** optimization process was conducted using a standard Quantum Particle Swarm Optimization,while the position error estimate for all given sets of weighted signals was performed using aMultilayer Perceptron(MLP)neural *** to our previous research works,the MLP architecture was improved to three hidden layers and its learning parameters were finely *** experimental results led to the 20%reduction of the positioning error when a suitable set of signal weights was calculated in the optimization *** final achieved value of 0.725 m of the location incertitude shows a sensible improvement compared to our previous results.

关键词： QPSO indoor localization fingerprinting neural networks WiFi WSN

Roles of fermented plant-,dairy-and meat-based foods in the modulation of allergic responses

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Food Science and Human Wellness 2023年第3期12卷 691-701页

作者： Muhamad Hafi z abd Rahim Nur Hazlin Hazrin-Chong Hanis Hazeera Harith Wan abd Al Qadr Imad Wan-Mohtar Rashidah Sukor Faculty of Food Science and Technology Universiti Putra Malaysia43400 SerdangSelangorMalaysia Department of Biological Sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia Faculty of Medicine and Health Sciences Universiti Putra Malaysia43400 SerdangSelangorMalaysia Functional Omics and Bioprocess Development Laboratory Institute of Biological SciencesFaculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Laboratory of Food Safety and Food Integrity Institute of Tropical Agriculture and Food SecurityUniversiti Putra Malaysia43400 SerdangSelangorMalaysia

This review attempts to delineate the effects and roles of fermented foods on allergic responses(AR),specifically from milk,plant,and meat *** for AR alleviation and aggravation were noted for many different fermented food *** outcomes on AR through fermented foods could be linked to microbial hydrolysis of food allergens,improvement in gut microbiota robustness,and modulation of the immune system that promotes a balance between T helper 1(Th1)and Th2 *** on plant-based,non-protein rich fermented foods tend to show more favourable results compared to those on meat-based or protein-rich *** usage of specific and known starter cultures are helpful in alleviating AR,as in the case for many yogurt,Kefir or Dahi *** fermentation time was also deemed important,exemplified in studies that showed inefficient AR reduction through consumption of fresh ***,formation of new allergens through fermentation of certain meat-based foods,or by using specific fermenting microbes(*** sp.),is ***,combination of starter cultures and food substrates must be considered in preventing or eliminating AR from intake of these *** review may aid consumers to make informed decision during the consumption of fermented food.

关键词： Allergy Fermented food Milk-based allergens Plant-based allergens Animal-based allergens

A Grid-tied PV Inverter with Sag-severity-independent Low-voltage Ride Through, Reactive Power Support, and Islanding Protection

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1300-1311页

作者： Muhammad Talha Siti Rohani S.Raihan Nasrudin abd.Rahim UM Power Energy Dedicated Advanced Center(UMPEDAC) University of Malaya IEEE

This paper proposes a grid-tied photovoltaic(PV)inverter capable of low-voltage ride through(LVRT), reactive power support, and islanding protection. Unlike other LVRT inverters, the proposed inverter is independent of sag severity while maintaining the maximum power-point tracking(MPPT)under normal and faulty conditions. The addition of an energy storage buffer stage mitigates the DC-link voltage surge during sags. At the same time, the inverter injects the reactive power during back-to-back sags of variable depths. The control system of the inverter generates the appropriate reference signals for normal, LVRT, and anti-islanding modes while the MPPT continues running. The salient features of the proposed inverter are:(1) active power injection under normal grid conditions;(2)sag-depth independent LVRT with reactive power support;(3)no DC-link fluctuations;(4) continuous MPPT mode;and(5) simultaneous LVRT and anti-islanding support during a grid outage. The inverter demonstrates an uninterrupted operation and seamless transition between various operating modes. Simulations and the experimental prototype have been implemented to validate the efficacy of the proposed PV inverter.

关键词： Low-voltage ride through(LVRT) Sag maximum power point tracking(MPPT) single-phase photovoltaic(PV)inverter PV-battery system

Depositional Environment,Petrophysical Evaluation and Electrical Properties of Zeit Formation,Northwestern Shore of Gulf of Suez,Egypt

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Journal of Earth Science 2024年第5期35卷 1720-1737页

作者： Mohamed M.Gomaa Emad A.abd El Aziz Geophysical Sciences Department National Research CentreEl-Behoos St.DokkiCairo 12622Egypt

The Zeit sand reservoir is one of the most prolific formations at Northwestern side of the Gulf of *** this research we will try to coordinate between electrical,petrophysical properties,depositional environment and facies discrimination in order to evaluate the hydrocarbon potentiality of studied Zeit *** statistical parameters for potassium(K),thorium(Th)and Th/U ratio contents have a general increase towards northwestern parts,whereas uranium(U)content has a general increase towards southeastern *** sandstone facies is distinguished from the other facies by its thorium content>4 ppm.U has high carbonate content(U≥1 ppm).Rocks'electrical properties vary greatly depending on a number of *** measurements were taken at frequencies range of(5×10^(-4)Hz-100 kHz)for fully saturated samples(clayey sandstone)with NaCl(20 gm/L).As salinity,clay content,and frequency increase,consequently does the electrical *** continental condition are present in northwestern part(back-sea)which is distinguished by high K percent,high Th,high Th/U ratio,and low U *** K,Th,and Th/U ratio contents,with high U contents,characterize the marine depositional environment that existed around the east and southeastern parts(foresea coincide with the dipping of strata).Furthermore,the studied Zeit Formation has good petrophysical properties that coincide with marine *** middle and eastern parts(around ISS-94 and CSS-288)is a good reservoir(porosity 36%-39%,shale content<15%,hydrocarbon saturation 71%-92%,and net pay thickness 17-63 feet).

关键词： Zeit Formation petrophysical evaluation depositional environment Spectral Gamma Ray electrical properties gulf of Suez sedimentology

Refractive errors and biometry of primary angle-closure disease in a mixed Malaysian population

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International Journal of Ophthalmology(English edition) 2017年第8期10卷 1246-1250页

作者： Jelinar Mohamed-Noor Dhaniah abd-Salam Department of Ophthalmology Hospital Kuala Lumpur JalanPahang Kuala Lumpur 50586 Malaysia

AIM： To assess the refractive status, anterior chamber depth （ACD） and axial length （AL） of patients with primary angle-closure disease （PACD）. METHODS： Retrospective cohort. Data was collected from charts of all PACD patients treated from April 2013 to December 2015. Analysis was done on 137 patient charts with complete biometric data. Patient demographics, PACD type, refractive status （spherical equivalent）, ACD and AL were studied. RESULTS： The median age of 137 subjects [53 with primary angle-closure suspects （PACS）, 27 with primary angle- closure （PAC） and 57 with primary angle-closure glaucoma （PACG）] was 68y （range 21-88y）. The majority was Chinese （n=68; 49.6%） and most of them were women （n=75; 54.7%）. The distribution of myopia （n=51; 37.2%） and hyperopia （n=49; 35.8%） was similar. The ACD was shallower in myopes compared to hyperopes （P=-0.02） and emmetropia （P=-0.049） but the AL was not significantly different between groups. There were no patients blind from PACG. CONCLUSION： Both myopia and hyperopia can occur in PACD. Despite a shallower ACD in angle closure myopes, the AL was not different between groups.

关键词： primary angle-closure suspect primary angle- closure primary angle-closure glaucoma anterior chamber depth axial length

Radionuclides measurements and mineralogical studies on beach sands, East Rosetta Estuary, Egypt

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Chinese Journal Of Geochemistry 2013年第2期32卷 146-156页

作者： abd El Wahab M. El Nahas H.A. Physics Department Faculty of Women for Arts Science and Education Ain Shams University Cairo P.O 11757 Egypt Nuclear Materials Authority Cairo P.O. Box 530 Egypt

Radiometric measurements were carried out for the beach sands from East Rosetta estuary to determine the activity concentrations of 238 U, 226 Ra, 232 Th, and 40 K, using a Hyper Pure Germanium spectrometer, to estimate the dose rates and radiation hazard indices. The average specific activities are 778.20 Bq/kg for 238 U; 646.89 Bq/kg for 226 Ra; 621.92 and 627.85 Bq/kg for the 222 Rn daughters 214 Pb and 214 Bi respectively. The average specific activity of 232 Th is 1510.25 Bq/kg, while the calculated specific activity for 40 K has an average of 8.41 Bq/kg. The average specific activity of 235 U is 38.61 Bq/kg. The average absorbed dose rate is 1211.36 nGy/h, 20 times higher than the estimated average global primordial radiation of 60 nGy/h and 6 times higher than that of the world range (10-200 nGy/h). The radium equivalent (Ra eq ) values are from 6 to 9 times the recommended value. The internal and external hazard indices (H int , H ex ) indicate that their values are from 6 to 11 times the permissible values of these indices. These higher values may be due to the presence of economic heavy minerals containing radionuclides as zircon and monazite as well as some trace minerals, thorite and uranothorite. The mineralogical study indicates the beach sands contain heavy minerals, zircon, monazite, rutile, ilmenite, leucoxene, magnetite and garnet. The average abundance of zircon is 0.175 wt% ranging from 0.125 wt% to 0.239 wt%, while it is 0.004wt% ranging from 0.001 wt% to 0.007 wt% for monazite. The average abundance is 0.087 wt% for rutile; 2.029 wt% for ilmenite; 1.084 wt% for magnetite; 0.384 wt% for leucoxene and 0.295 wt% for garnet.

关键词：放射性核素海滩砂矿物学核素测量河口平均丰度埃及辐射测量

Spectral Solutions of Linear and Nonlinear BVPs Using Certain Jacobi Polynomials Generalizing Third- and Fourth-Kinds of Chebyshev Polynomials

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Computer Modeling in Engineering & Sciences 2021年第3期126卷 955-989页

作者： W.M.abd-Elhameed Asmaa M.Alkenedri Department of Mathematics Faculty of ScienceCairo UniversityGizaEgypt Department of Mathematics College of ScienceUniversity of JeddahJeddahSaudi Arabia

This paper is dedicated to implementing and presenting numerical algorithms for solving some linear and nonlinear even-order two-point boundary value *** this purpose,we establish new explicit formulas for the high-order derivatives of certain two classes of Jacobi polynomials in terms of their corresponding Jacobi *** two classes generalize the two celebrated non-symmetric classes of polynomials,namely,Chebyshev polynomials of third-and *** idea of the derivation of such formulas is essentially based on making use of the power series representations and inversion formulas of these classes of *** derived formulas serve in converting the even-order linear differential equations with their boundary conditions into linear systems that can be efficiently ***,and based on the first-order derivatives formula of certain Jacobi polynomials,the operational matrix of derivatives is extracted and employed to present another algorithm to treat both linear and nonlinear two-point boundary value problems based on the application of the collocation *** analysis of the proposed expansions is *** numerical examples are included to demonstrate the validity and applicability of the proposed algorithms.

关键词： Jacobi polynomials high-order boundary value problems Galerkin method collocation method connection problem convergence analysis

Effect of rotation on the surface wave propagation in magneto-thermoelastic materials with voids

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Journal of Ocean Engineering and Science 2018年第4期3卷 334-342页

作者： A.M.Farhan A.M.abd-Alla Physics Department Faculty of ScienceJazan UniversitySaudi Arabia Physics Department Faculty of ScienceZagzig UniversityEgypt Mathematics Department Faculty of ScienceSohag UniversityEgypt

The present investigation is focused on studying the surface wave propagation in a generalized magneto-thermoelastic materials taking(Green Lindsay)model with *** general surface wave speed is derived to study the effects of magnetic field and rotation on surface wave in the presence of *** addition the present study can be comprehensively applied to the magneto-thermoelastic medium with *** possible non-dimensional frequency of surface wave propagation has been obtained as the solution of an algebraic equation involving a determinant whose elements contain the material parameters,the direction of applied magnetic field and rotation of surface wave *** comparisons for the physical quantities are established numerically and represented graphically in different cases with respect to the used effects.

关键词： Green Lindsay theory Thermoelasticity Surface waves.

Fungal inoculation induces agarwood in young Aquilaria malaccensis trees in the nursery

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Journal of Forestry Research 2014年第1期25卷 201-204页

作者： Rozi MOHAMED Phai Lee JONG abd Kudus KAMZIAH Forest Biotechnology Laboratory Department of Forest ManagementFaculty of ForestryUniversiti Putra Malaysia Department of Forest Management Faculty of ForestryUniversiti Putra Malaysia

Fungi are often used to induce agarwood inAquilariatrees. This study was conducted to evaluate the effect of several fungi on agarwood formation over time in youngAquilaria malaccensis （Lam.） trees. Typical changes in the length and light intensity of the resulting discoloration were observed after three and six month periods following inoculation. Wood samples were observed microscopically and classified into several light intensity groups. The discoloration length was meas-ured longitudinally. The duration after inoculation affected the mean of discoloration length： the 6-month old sample （1.70 cm） had a wider discoloration zone when compared to the 3-month old sample （1.17 cm）. When measuring the discoloration intensity, a positive relationship with time was perceived. Digital images, captured using a camera-equipped microscope, revealed that wood samples collected after six months appeared to be 1.8-times darker than after three months. We concluded that time, not the species of any of the tested fungi, had significant effect on discoloration length and intensity. Gas chromatography/mass spec-trometry （GCMS） analysis of the 6-month old sample yielded some important agarwood compounds such as benzylacetone, anisylacetone, guaiene and palustrol. This demonstrates that the tested fungi have the ability to induce agarwood formation in nurseryA. malaccensis trees.

关键词： Artificial inoculation discoloration zone fungi guaiene palustrol