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Earth and Planetary Physics 2025年第02期9卷 375-386页

作者： Anwar Santoso Sismanto Sismanto Rhorom Priyatikanto Eddy Hartantyo Dyah R.Martiningrum research Center for Space National Research and Innovation Agency Physics Department Faculty of Mathematics and Natural Sciences Gadjah Mada University Geophysics Laboratory Physics Department Faculty of Mathematics and Natural Sciences Gadjah Mada University research Center for Climate and Atmosphere National Research and Innovation Agency School of graduate studies Faculty of Science Universiti Teknologi Malaysia

Proper knowledge of the nature of geomagnetic storms and their relationships with the conditions of the space environment at the outer part of the Earth's magnetosphere（bow shock nose） is essential to increase our resilience to space weather disturbances. In this article, we present an analysis of the interplanetary magnetic field（IMF） and solar wind parameters relevant to 100 geomagnetic storms in Solar Cycle 24. We revisit the relationship between the minimum disturbance storm time index(Dstmin), the minimum southward IMF(BS, min), the maximum solar wind density(NSW, max) and speed(Vmax), and the lag time between the extrema(dT（Bz, N）,dT（Bz, V）). We end with a regression formula that fits the data, with a coefficient of determination of 0.58, a root mean square error of 21.30 nT, and a mean absolute error of 15.87 nT. Even though more complex machine learning models can outperform this model, it serves as a theoretically sensible alternative for understanding and forecasting geomagnetic storms.

关键词： geomagnetic storm interplanetary magnetic field(IMF) solar wind space weather

Variational Bayesian Tensor Quantile Regression

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Acta Mathematica Sinica,English Series 2025年第2期41卷 733-756页

作者： Yunzhi Jin Yanqing Zhang Yunnan Key Laboratory of statistical Modeling and Data Analysis Yunnan UniversityKunming 650091P.R.China Yunnan Key Laboratory of statistical Modeling and Data Analysis Southwest United Graduate SchoolYunnan UniversityKunming 650091P.R.China

Quantile regression is widely used in variable relationship research for statistical *** quantile regression model is based on vector-valued covariates and can be efficiently estimated via traditional estimation ***,many modern applications involve tensor data with the intrinsic tensor *** quantile regression can not deal with tensor regression issues *** this end,we consider a tensor quantile regression with tensor-valued covariates and develop a novel variational Bayesian estimation approach to make estimation and prediction based on the asymmetric Laplace model and the CANDECOMP/PARAFAC decomposition of tensor *** incorporate the sparsity of tensor coefficients,we consider the multiway shrinkage priors for marginal factor vectors of tensor *** key idea of the proposed method is to efficiently combine the prior structural information of tensor and utilize the matricization of tensor decomposition to simplify the complexity of tensor coefficient *** coordinate ascent algorithm is employed to optimize variational lower *** studies and a real example show the numerical performances of the proposed method.

关键词： Asymmetric Laplace model CANDECOMP PARAFAC decomposition matricization tensor quantile regression variational Bayesian

Combined Effect of Honey from Central West Brazil on Bacterial Membrane Permeability

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Journal of Biosciences and Medicines 2025年第1期13卷 316-337页

作者： Mariana Lenina Menezes Aleixo Joziane da Cruz Mendonça Rafael Bruno Rocha Benevides Larissa Maria Scalon Lemos Carla Galbiati graduate Program in Environmental Sciences (PPGCA) Office of Research and Graduate Studies State University of Mato Grosso (UNEMAT) Cceres Mato Grosso Brazil faculty of Agrarian Sciences State University of Mato Grosso (UNEMAT) Cceres Mato Grosso Brazil Departament of Nursing Faculty of Health Sciences State University of Mato Grosso (UNEMAT) Cceres Mato Grosso Brazil

Honey, an apicultural product with a complex chemical composition, contains numerous bioactive compounds with potential antimicrobial effects. This study investigated the effect of Apis mellifera honey from Brazil’s Central-West Region, combined with antibiotics, on bacterial membrane permeability, exploring the contributions of bioactive compounds and the botanical origin of honey. Six fresh Apis mellifera honey samples and their fractions (hexane and ethyl acetate) were analyzed, for a total of 18 samples. The bacteria Staphylococcus epidermidis, Helicobacter pylori and Enterococcus faecalis were used for antibacterial activity tests, which included minimum inhibitory concentration (MIC) determination and synergistic effect (checkerboard) assays. The total polyphenol and flavonoid contents were quantified, and the botanical origin was determined based on pollen analysis. The tested honey samples significantly affected bacterial membrane permeability when combined with rifampicin and clarithromycin. Although many honey-derived bioactive compounds, when isolated, did not exhibit significant activity against these bacteria, the additive or synergistic effect of multiple compounds acting on different targets appears to potentiate the antibacterial action. Descriptive statistical analysis, including means and 95% confidence intervals, confirmed the relevance of the findings. This study has provided an important discovery: Honey has an effect on bacterial membrane permeability, although the specific mechanisms involved in this process require further investigation.

关键词： Honey Mechanism of Action Antibacterial Bacterial Membrane Permeability Bioactive Compounds

Enhanced humidity-sensing performance of(Zr4+/Sb5+)-codoped TiO2 ceramics with giant dielectric properties

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Journal of Advanced Ceramics 2025年第1期14卷 71-80页

作者： Noppakorn Thanamoon Nateeporn Thongyong Kaniknun Sreejivungsa Narong Chanlek Prasit Thongbai Giant Dielectric and Computational Design research Group(GD-CDR) Department of PhysicsFaculty of ScienceKhon Kaen UniversityKhon Kaen 40002Thailand Institute of Nanomaterials research and Innovation for Energy(IN-RIE) Faculty of ScienceKhon Kaen UniversityKhon Kaen 40002Thailand Synchrotron Light research Institute(Public Organization) Nakhon Ratchasima 30000Thailand Department of Fundamental Science Faculty of Science and TechnologySurindra Rajabhat UniversitySurin 32000Thailand

In this study,(Zr0.5/Sb0.5)xTi1−xO2 ceramics with x=0.01,0.025,and 0.05 were prepared via the solid-state reaction(SSR)method.A pure phase of rutile TiO2 with a highly dense microstructure and relative density(ρr)higher than 96%was detected in all the sintered *** mean grain size was reduced,but the dielectric permittivity(ε′)*** giant dielectric properties were tested to investigate their possible use in capacitors and capacitive humidity sensors under various relative humidity(RH)levels ranging from 30%to 95%RH.(Zr0.5/Sb0.5)xTi1−xO2 ceramics present a giantε′of~(4.82‒7.39)×104 and a low loss tangent(tanδ≈0.031‒0.106 at 1 kHz),indicating attractive giant dielectric *** observation was attributed to both intrinsic and extrinsic *** the humidity sensing properties,the best humidity sensing properties were observed in the ceramics with x=0.05,with a sensitivity of~237%pF/%RH,a low hysteresis error(~1.6%),and fast response/recovery time of~12 s/16 s at 1 *** point defects of Sb⋅Ti and V⋅⋅O were claimed to be active centers for water ***,impedance spectroscopy(IS)analysis revealed that changes in the dielectric properties with varying RH levels were also influenced by interfacial polarization at the surface layer and grain boundaries.

关键词： humidityysensor humidity-sensing properties giant/colossal dielectric permittivity X-ray photoelectron spectroscopy(XPS) pointdefect TiO2

Walking for Mental Health:Effects of Mobile-Based Walking on Stress and Affectivity in College Students

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International Journal of Mental Health Promotion 2025年第2期27卷 179-191页

作者： Ye Hoon Lee Juhee Hwang Division of Global Sport Industry Hankuk University of Foreign StudiesGyeonggi-do17035Republic of Korea graduate School of Global Sports Hankuk University of Foreign StudiesSeoul02450Republic of Korea

Objectives:Recent research has shown that college students experience high levels of stress from various sources,which contribute to heightened rates of psychological distress and make them particularly vulnerable to mental health ***,we conducted a study,aimed to analyze the influence of a mobile-based walking routine on mental health outcomes,such as perceived stress and positive and negative ***:The participants were divided into two groups:the walking group(N=23)and the control group(N=24).The walking group engaged in an approximately 25-min walking session for at least 3 days per week,which was carefully monitored and facilitated with the help of the Nike Run Club *** statistical analysis of the quantitative data was carried out with the help of SPSS *** addition to calculating descriptive statistics,we conducted an independent samples t-test,a repeated-measures ANOVA,and a paired sample t-test to analyze the effectiveness of the ***:A repeated-measures ANOVA revealed that the walking group exhibited significant reductions in perceived stress(t=2.03,p=0.049,Cohen’s D=0.60)and negative affect(t=2.19,p=0.033,Cohen’s D=0.65)after the intervention,whereas the control group showed no significant changes across time in any of the proposed ***:The results of the study continue to be indicative of the positive effects of regular walking on perceived stress and negative affect,preserving its role as a straightforward and accessible tool for reducing stress and negative affect.

关键词： Mental health low-intensity exercise mental health outcomes mobile intervention positive and negative affect

Morphologically controlled synthesis of MgFe-LDH using MgO and succinic acid for enhanced arsenic adsorption:Kinetics,equilibrium,and mechanism studies

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Journal of Environmental Sciences 2025年第2期148卷 637-649页

作者： Yusuf Olalekan Zubair Shigeshi Fuchida Keishi Oyama Chiharu Tokoro graduate school of Creative Science and Engineering Waseda UniversityOkubo 3-4-1ShinjukuTokyo169-8555Japan Department of Marine Resources and Energy Tokyo University of Marine Science and Technology4-5-7 KonanMinato-KuTokyo 108-8477Japan faculty of Science and Engineering Waseda University3-4-1 OkuboShinjuku-kuTokyo 169-8555Japan faculty of Engineering The University of Tokyo7-3-1 HongoBunkyo-KuTokyo 113-8656Japan

In this study,we investigated improving the performance of a layered double hydroxide(LDH)for the adsorption of As(III)and As(V)by controlling the morphology of LDH *** LDH was synthesized via a simple coprecipitation method using barely soluble MgO as a precursor and succinic acid(SA)as a morphological control *** the LDH crystals with carboxylate ions(RCOO−)derived from SA caused the crystals to develop in a radial *** changed the pore characteristics and increased the density of active surface ***,SA/MgFe-LDH showed excellent affinity for As(III)and As(V)with maximum sorption densities of 2.42 and 1.60 mmol/g,*** comparison,the pristine MgFe-LDH had sorption capacities of 1.56 and 1.31 mmol/g for As(III)and As(V),*** LDH was effective over a wide pH range for As(III)adsorption(pH 3-8.5)and As(V)adsorption(pH 3-6.5).Using a combination of spectroscopy and sorption modeling calculations,the main sorption mechanism of As(III)and As(V)on SA/MgFe-LDH was identified as inner-sphere complexation via ligand exchangewith hydroxyl group(-OH)and RCOO−.Specifically,bidentate As-Fe complexeswere proposed for both As(III)and As(V)uptake,with the magnitude of formation varying with the initial As ***,the As-laden adsorbent had satisfactory stability in simulated real landfill *** findings demonstrate that SA/MgFe-LDH exhibits considerable potential for remediation of As-contaminated water.

关键词： Arsenic Heavy magnesium oxide Succinic acid Layered double hydroxide Adsorption Bidentate complex Stabilization

Estimation of the Stress-Strength Reliability for Exponentiated Pareto Distribution Using Median and Ranked Set Sampling Methods

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Computers, Materials & Continua 2020年第8期64卷 835-857页

作者： Amer Ibrahim Al-Omari Ibrahim M.Almanjahie Amal S.Hassan Heba F.Nagy Department of Mathematics Faculty of ScienceAl al-Bayt UniversityMafraq25113Jordan Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia statistical research and studies Support Unit King Khalid UniversityAbha62529Saudi Arabia faculty of graduate studies for statistical research Cairo UniversityGiza12613Egypt

In reliability analysis,the stress-strength model is often used to describe the life of a component which has a random strength(X)and is subjected to a random stress(Y).In this paper,we considered the problem of estim... 详细信息

关键词： Stress-Strength model ranked set sampling median ranked set sampling maximum likelihood estimation mean square error

Kumaraswamy Inverted Topp–Leone Distribution with Applications to COVID-19 Data

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Computers, Materials & Continua 2021年第7期68卷 337-358页

作者： Amal S.Hassan Ehab M.Almetwally Gamal M.Ibrahim faculty of graduate studies for statistical research Cairo UniversityGiza12613Egypt faculty of Business Administration Delta University of Science and TechnologyMansoura35511Egypt High Institute for Management Sciences Belqas35511Egypt

In this paper, an attempt is made to discover the distributionof COVID-19 spread in different countries such as;Saudi Arabia, Italy,Argentina and Angola by specifying an optimal statistical distribution for analyzing the mortality rate of COVID-19. A new generalization of the recentlyinverted Topp Leone distribution, called Kumaraswamy inverted Topp–Leonedistribution, is proposed by combining the Kumaraswamy-G family and theinverted Topp–Leone distribution. We initially provide a linear representationof its density function. We give some of its structure properties, such as quantile function, median, moments, incomplete moments, Lorenz and Bonferronicurves, entropies measures and stress-strength reliability. Then, Bayesian andmaximum likelihood estimators for parameters of the Kumaraswamy invertedTopp–Leone distribution under Type-II censored sample are *** estimator is regarded using symmetric and asymmetric loss functions. As analytical solution is too hard, behaviours of estimates have beendone viz Monte Carlo simulation study and some reasonable comparisonshave been presented. The outcomes of the simulation study confirmed theefficiencies of obtained estimates as well as yielded the superiority of Bayesianestimate under adequate priors compared to the maximum likelihood *** to COVID-19 in some countries showed that the new distributionis more appropriate than some other competitive models.

关键词： Kumaraswamy-G family maximum likelihood Bayesian method COVID-19 moments quantile function stress-strength reliability

Magnetic Field Effect and Heat Transfer of Nanofluids within Waveform Microchannel

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1957-1973页

作者： Mehdi Moslemi Motahare Mahmoodnezhad S.A.Edalatpanah Sulima Ahmed Mohammed Zubair Hamiden Abd El-Wahed Khalifa Ayandegan Institute of Higher Education TonekabonIran Department of Mathematics College of Science and ArtsQassim UniversityAr RassSaudi Arabia Operations research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGizaEgypt

In this research,a numerical study of mixed convection of non-Newtonian fluid and magnetic field effect along a vertical wavy surface was investigated.A simple coordinate transformation to transform wavy surface to a flat surface is employed.A cubic spline collocation numerical method is employed to analyze transformed *** effect of various parameters such as Reynolds number,volume fraction 0-,Hartmann number,and amplitude of wave length was evaluated in improving the performance of a wavy *** to the presented results,the sinusoidal shape of the microchannel has a direct impact on heat *** increasing the microchannel wave amplitude,the Nusselt number has *** the other hand,increasing the heat transfer in the higher wavelength ratio corrugated channel is seen as an effective method of increasing the heat transfer,especially at higher Reynolds *** results showed that with increasing Hartmann numbers,the flow line near thewall becomesmore regular and,according to the temperature gradient created,theNusselt number growth.

关键词： Heat transfer magnetic field nano fluid vorticity wavy micro channel

Entropy Bayesian Analysis for the Generalized Inverse Exponential Distribution Based on URRSS

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Computers, Materials & Continua 2021年第12期69卷 3795-3811页

作者： Amer I.Al-Omari Amal S.Hassan Heba F.Nagy Ayed R.A.Al-Anzi Loai Alzoubi faculty of Science Department of MathematicsAl al-Bayt UniversityMafraq25113Jordan faculty of graduate studies for statistical research Cairo UniversityGiza12613Egypt Department of Mathematics College of Science and Human Studies at Hotat SudairMajmaah UniversityMajmaah11952Saudia Arabia

This paper deals with the Bayesian estimation of Shannon entropy for the generalized inverse exponential *** that the observed samples are taken from the upper record ranked set sampling(URRSS)and upper record values(URV)*** of Bayesian estimators are derived depending on a gamma prior distribution considering the squared error,linear exponential and precautionary loss functions,in addition,we obtain Bayesian credible *** random-walk Metropolis-Hastings algorithm is handled to generate Markov chain Monte Carlo samples from the posterior ***,the behavior of the estimates is examined at various record *** output of the study shows that the entropy Bayesian estimates under URRSS are more convenient than the other estimates under URV in the majority of the ***,the entropy Bayesian estimates perform well as the number of records *** obtained results validate the usefulness and efficiency of the URV *** data is analyzed for more clarifying purposes which validate the theoretical results.

关键词： Shannon entropy generalized inverse exponential distribution Bayesian estimators loss function ranked set sampling markov chain