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Intelligent Automation & Soft Computing 2023年第3期35卷 2589-2601页

作者： Tariq T.Alshammari Mohd Tahir Ismail Nawaf N.hamadneh S.Al Wadi Jamil J.Jaber Nawa Alshammari Mohammad h.saleh School of Mathematical Science Universiti Sains MalaysiaPenangMalaysia Department of Risk Management and Insurance Faculty of BusinessThe University of JordanJordan Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadhSaudi Arabia

In this study,we proposed a new model to improve the accuracy of fore-casting the stock market volatility *** hypothesized model was validated empirically using a data set collected from the Saudi Arabia stock Exchange(Tada-wul).The data is the daily closed price index data from August 2011 to December 2019 with 2027 *** proposed forecasting model combines the best maximum overlapping discrete wavelet transform(MODWT)function(Bl14)and exponential generalized autoregressive conditional heteroscedasticity(EGARCh)*** results show the model's ability to analyze stock market data,highlight important events that contain the most volatile data,and improve forecast *** results were compared from a number of mathematical mod-els,which are the non-linear spectral model,autoregressive integrated moving aver-age(ARIMA)model and EGARCh *** performance of the forecasting model will be evaluated based on some of error functions such as Mean absolute percentage error(MAPE),Mean absolute scaled error(MASE)and Root means squared error(RMSE).

关键词： Predictive analytics mathematical models volatility index EGARCh model

Unveiling the Optimal Interfacial Synergy of Plasma-Modulated Trimetallic Mn-Ni-Co Phosphides:Tailoring Deposition Ratio for Complementary Water Splitting

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Energy & Environmental Materials 2023年第2期6卷 129-141页

作者： Kholoud E.Salem Amina A.saleh Ghada E.Khedr Basamat S.Shaheen Nageh K.Allam Energy Materials Laboratory(EML) School of Sciences and EngineeringThe American University in CairoNew Cairo 11835Egypt

Designing highly active,durable,and nonprecious metal-based bifunctional electrocatalysts for overall water electrolysis is of urgent scientific importance to realize the sustainable hydrogen production,which remains a grand ***,an innovative approach is demonstrated to synthesize flower-like 3D homogenous trimetallic Mn,Ni,Co phosphide catalysts directly on nickel foam via electrodeposition followed by plasma *** electrochemical activity of the catalysts with varying Mn:Ni:Co ratios is assessed to identify the optimal composition,demonstrating that the equimolar trimetallic phosphide yields an outstanding hER catalytic performance with a current density of 10 mA cm^(-2) at an ultra-low overpotential of~14 mV,outperforming the best reported *** is asserted by the DFT calculations,revealing strong interaction of the metals and the P atom,resulting in enhanced water activation and optimized G_(h)^(*)values for the hER ***,this optimal composition appreciably catalyzes the OER by exposing more intrinsic active species in-situ formed on the catalyst surface during the ***,the Mn_(1)-Ni_(1)-Co_(1)-P-(O)/NF catalyst exhibits a decreased overpotential of~289 mV at 10 mA cm^(-2).More importantly,the electrocatalyst sustains perfect durability up to 48 h at a current density of 10 mA cm^(-2) and continued 5000 cycling stability for both hER and ***,the assembled MNC-P/NF||MNC-P/NF full water electrolyzer system attains an extremely low cell voltage of 1.48 V at 10 mA cm^(-2).Significantly,the robust stability of the overall system results in a remarkable current retention of~96%after a continuous 50-h ***,this study provides a facile design and a scalable construction of superb bifunctional ternary MNC-phosphide electrocatalysts for efficient electrochemical energy production systems.

关键词： DFT overall water splitting oxygen evolution reaction(OER)/hydrogen evolution reaction(hER) plasma ternary metallic phosphides(MnNiCo)

Bimetallic zeolitic imidazolate framework-derived substrate-free anode with superior cyclability for high-capacity lithium-ion batteries

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Journal of Materials Science & Technology 2021年第8期67卷 116-126页

作者： Bhavana Joshi Edmund samuel Yong-il Kim Govindasami Periyasami Mostafizur Rahaman sam S.Yoon School of Mechanical Engineering Korea UniversitySeoul136-713Republic of Korea Department of Physics NES Science CollegeSwami Ramanand Teerth Marathwada UniversityLatur RoadNandedMaharashtra431606India Department of Chemistry College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

Freestanding carbon nanofibers loaded with bimetallic hollow nanocage structures were *** nanocages inherited the rhombic dodecahedral morphology of the zeolitic imidazolate framework(ZIF)precursors,ZIF-8 and *** anode materials for lithium-ion batteries(LIBs),the bimetallic nanocage-loaded freestanding carbon nanofibers effectively buffered volume expansions and alleviated pulverization through their different reduction and oxidation *** higher capacities of the composite anodes arose via the formation of the Li_(x)Zn alloy and Li_(2)O by Zn and Co ions,respectively,and the enhanced conductivity conferred by the carbon nanofibers.A synergistic effect of the composite components toward the strong electrochemical performance(688 m A h·g^(-1)at 1200 m A·g^(-1))of the bimetallic nanocage-loaded fibers was demonstrated through the superior long-term stability of the anode(1048 m A h·g^(-1)after 300 cycles at 100 m A·g^(-1)),suggesting that the fabricated anode can be a promising material for use in portable LIBs.

关键词： Carbon nanofiber Nanostructure Composite anode Zeolitic imidazolate framework

Autopilot Control Synthesis for Path Tracking Maneuvers of Underwater Vehicles

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China Ocean Engineering 2011年第2期25卷 237-249页

作者： sam-Sang YOU hyeung-Sik ChOI hwan-Seong KIM han-Il PARK School of Mechanical and Energy Systems Engineering Korea Maritime University Department of Logistics System Engineering Korea Maritime University Department of Ocean Engineering Korea Maritime University

This paper is concerned with the robust control synthesis of autonomous underwater vehicle （AUV） for general path following maneuvers. First, we present maneuvering kinematics and vehicle dynamics in a unified framework. Based on h∞ loop-shaping procedure, the 2-DOF autopilot controller has been presented to enhance stability and path tracking. By use of model reduction, the high-order control system is reduced to one with reasonable order, and further the scaled low-order controller has been analyzed in both the frequency and the time domains. Finally, it is shown that the autopilot control system provides robust performance and stability against prescribed levels of uncertainty.

关键词： underwater vehicle path following 2-DOF control synthesis h∞ loop-shaping plant uncertainty model reduction

Cancer Risk of Inhalation Exposure to Cd, Cr, As, Be and Ni in Ambient Air

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Journal of Environmental Protection 2017年第3期8卷 290-300页

作者： heba M. Adly saleh A. K. saleh Abdullah A. Saati sameer h. Fatani Biochemistry Department Faculty of Medicine Umm Al-Qura University Makkah KSA Oncology Diagnostic Unit Faculty of Medicine Ain Shams University Cairo Egypt Community Medicine Department Faculty of Medicine Umm Al-Qura University Makkah KSA

Particulate matter may comprise toxic trace elements with carcinogenic effects. Of these trace elements, Cadmium (Cd), Chromium (Cr), Arsenic (As), Beryllium (Be) and Nickel (Ni) are classified as probable human carcinogens. During the annual hajj pilgrimage, 2.3 million pilgrims stay in Makkah, Saudi Arabia;the increased vehicle traffic contributes to elevated concentrations of particulate matter. We aimed to determine the excess cancer risk (ECR) associated with inhalation exposure in the Makkah population. This study was conducted in the Arafat area, which is a highly-crowded area during hajj. Inductively coupled plasma-mass spectrometry (ICP-MS) was used for trace element analysis. ECR resulting from inhalation exposure to each metal was calculated in accordance with the unit risk suggested by the Integrated Risk Information System. In summer, including hajj, mean Cd, Cr, As, Be, and Ni atmospheric concentrations were 0.098, 0.008, 0.26, 0.03, and 0.012 μg/m3, respectively;in autumn, values were 0.06, 0.006, 0.16, 0.002, and 0.01 μg/m3, respectively. ECRs were 1.08 × 10𕒸, 7.21 × 10𕒸, 4.0 × 10𕒺, 4.6 × 10𕒺, and 2.4 × 10𕒺, respectively, exceeding the acceptable inhalation risk level (1.0 × 10𕒺) set by the US Environmental Protection Agency for each element. higher atmospheric trace element concentrations in summer were due to high temperatures that increased atmospheric turbulence, leading to a greater amount of re-suspended dust from roads and blowing sand particles. These findings can be used by relevant authorities while developing regulations and strategies for developing air quality management to improve the health of pilgrims;however, larger prospective studies are required to estimate ECR in different seasons.

关键词： Carcinogens Trace Elements Particulate Matter PM10

Synergetic NO reduction by biomass pyrolysis products simulating their reburning in circulating fluidized bed decoupling combustion

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1680-1689页

作者： hai-sam Do Tuyet-Suong Tran Zhennan han Xi Zeng Shiqiu Gao Guangwen Xu State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Institute of Industrial Chemistry and Energy Technology Shenyang University of Chemical TechnologyShenyang 110142China

The present work investigated the synergetic effect of pyrolysis-derived char,tar and gas(py-gas)on NO reduction,which may occur in circulating fluidized-bed decoupling combustion(CFBDC)system treating N-rich *** were carried out in a lab-scale drop-tube reactor for NO reduction by some binary mixtures of reagents including char/py-gas,tar/py-gas and tar/*** a specified total mass rate of0.15 g·min^-1 for NO-reduction reagent,the char/py-gas(binary reagent)enabled the best synergetic NO reduction in comparison with the *** existed effective interactions between char and some species in py-gas(i.e.,h2,Cxhy)during NO reduction by pyrolysis products,meanwhile the tar/py-gas or tar/char mixture only caused a positive effect when tar proportion was necessarily lowered to about 26%.On the other hand,the synergetic effects were not improved for all tested binary reagents by increasing the reaction temperature and residence time.

关键词： Biomass Pyrolysis Circulating fluidized bed NO reduction Synergetic effect Decoupling combustion

Electrical Transport Properties of La-BaTiO<sub>3</sub>

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Materials Sciences and Applications 2011年第7期2卷 716-720页

作者： A. I. Ali saleh h. Kaytbay 不详

The Electrical properties as a function of temperature were investigated at elevated temperatures (300 K - 800 K) on quenched samples of donor doped La-BaTiO3 system. The resistivity and carrier concentration increased with increasing temperature. The mobility of the sample shows exponential temperature dependence and the value of mobility is in well agreement with the theoretical values. From the conductivity data the activation energy was calculated (0.036 eV) and revealed that the conduction mechanism in this system is thermally activated.

关键词： hall Mobility Electrical Resistivity Microstructure and Donor Doped-BaTiO3

Evaluating Economic and Environmental Benefits of Integrating Solar Photovoltaics within Future Residential Buildings in Saudi Arabia

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Journal of Energy and Power Engineering 2010年第1期4卷 18-25页

作者： h.M. Taleb Y.M. Al-saleh School of Architecture University of Sheffield Sheffield S102TN UK Manchester Institute of Innovation Research University of Manchester Manchester M13 9PL UK

Renewable energy options, including solar power, are becoming increasingly viable alternatives to conventional sources of energy, such as oil, coal and natural gas. Solar Photovoltaic （PV） technology is one type of solar energy technologies that has recently received substantial attention because it offers the possibility of providing clean power sources for buildings. The aim of this paper is to examine the economic viability of using solar PV within future residential buildings in the oil-rich Saudi Arabia. Strictly speaking, the prospects of using the PV in order to provide 10% of the electricity to be consumed in the houses, which are going to be built in Sandi Arabia over the period 2010-2025, are examined. The study reveals that significant economic and environmental benefits could be realized as a result of such an endeavor.

关键词： Renewable energy solar photovoltaics Sandi Arabia residential buildings feasibility study.

The possible source of uranium mineralization in felsic volcanic rocks,Eastern Desert,Egypt of the Arabian-Nubian Shield:Constraints from whole-rock geochemistry and spectrometric prospection

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Acta Geochimica 2021年第5期40卷 819-845页

作者： Gehad.M.saleh Bahaa.M.Emad Ibrahim.B.Abdel Kader Rania.M.Sakr Nuclear Materials Authority El MaadiP.O.Box 530CairoEgypt

The present work deals with the detailed geology,mineralogy,geochemistry,and spectrometric prospection of the felsic volcanic rocks at the Eastern Desert,Egypt of the Arabian-Nubian *** volcanic rocks are an essential source for rare earth elements(REEs)and uranium occurrences in this *** are compositionally uniform with tholeiitic to calc-alkaline affinities,peraluminous and belong to the series of rhyolite with high-K *** exhibit more enrichment in high field strength elements(hFSE,***,Ta,Nd,Th,and U)and large-ion lithophile elements(LILE,*** and Rb)compared to the country rocks of the studied area,with REE ranging from 188.20 to 442.70 ppm and strong depletion in Ti,Sr,P with deep negative Eu *** felsic volcanic rocks were mostly generated from the partial melting of quartz-amphibolite facies accreted during the *** oddities of Zr-U-Th for the felsic volcanic rocks determine the involvement of crustal *** volcanic rocks are found in A-type suites of magma and represent highly fractionated rocks derived from rhyolitic magma,with insignificant interaction with continental crust in the low-pressure environment and during fractional *** volcanic rocks have higher values of radioactivity in which eU range from 0.5 to 121 ppm and eTh from 1.0 to 415.10 *** high values of eU and eTh can be ascribed to the mineralization of uranium and the presence of accessory minerals of radiogenic nature such as uranophane,uranothorite,zircon,and *** is considered as the mineral with most enriched uranium contents in the studied felsic volcanic rocks in which(UO2=87.30 wt%).Also,they are enriched with REE-bearing accessory minerals comprising allanite,titanite,and *** geological investigations of the felsic volcanic rocks in the studied areas are inappropriate to clear the feasible economic potentialities of rare earth elements and U occurrences;itemized and invaluable

关键词： Felsic volcanic rocks Geochemistry REE Uranium mineralization Egypt Arabian-Nubian Shield

The Radon Indoor Concentration Measurement in AI-Sader City, Baghdad

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Journal of Physical Science and Application 2016年第1期6卷 137-143页

作者： Asia h. A1-Mashhadani Adel Mehdi saleh

This paper presents the results of indoor radon concentrations measurements in homes in A1-Sader city/Baghdad, Iraq. Radon cup technique was used, which is a cylindrical chamber 5 cm in diameter and height of 7 cm, contains solid state nuclear track detector CR-39, were distributed in 30 houses for thirty days. Results of radon concentrations show that the radon concentration is below the limit recommended by ICRP. The annual effective dose is ranged from 1.1600 to 2.1632 mSv y-1 and it＇s within the limits permitted by the ICRP. Equilibrium Equivalent Concentration （EEC） values were calculated and ranged from 14.72960 Bq/m3 to 27.45344 Bq/m3. however, the results show that indoor 222Rn exposure for samples were ranged from 0.003978 to 0.007413 work level （WL）, then the values of working level month （WLM） were calculated, the minimum value was 0.004978WLM and the maximum value was 0.009277 WLM. The radon induced lung cancer risk and the percentage of induced lung cancer risk were ranged from 13.53723 to 25.23106 per million persons, with an average of about 18.58738 per million persons.

关键词： Radon concentration CR-39 track detector annual effective dose A1-Sadar city.