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An Adaptive Data-driven Method Based on Fuzzy Logic for Determining Power System Voltage Status

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 707-718页

作者： Sirwan Shazdeh Hêmin Golpîra Hassan Bevrani the SMGRC University of KurdistanSanandajIran Power Systems Modeling&Simulation lab Department of Electrical EngineeringUniversity of KurdistanKurdistanSanandaj 66177-15175Iran

This paper proposes an adaptive method based on fuzzy logic that utilizes data from phasor measurement units(PMUs) to assess and classify generating-side voltage trajectories. The voltage variable and its associated derivatives are used as the input variables of a fuzzy-logic block. in addition, the voltage trajectory is compared with the pre-selected pilot-bus voltage to make a reliable decision about the voltage operational state. Different types of short-term voltage dynamics are considered in the proposed method. The fuzzy membership functions are determined using a systematic method that considers the current situation of the voltage trajectory. Finally, the voltage status is categorized into four classes to determine appropriate remedial actions. The proposed method is validated on a iEEE 73-bus power system in a MATlaB environment.

关键词： Fuzzy logic fault-induced delayed voltage recovery phasor measurement unit(PMU) short-term voltage stability situational awareness voltage classification

Stellar structure model in hydrostatic equilibrium in the context of f(R)-gravity

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Research in Astronomy and Astrophysics 2017年第12期17卷 31-40页

作者： raíla Andr Gilberto M.Kremer Departamento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil Manipal Centre for Natural Sciences Manipal UniversityManipal 576104India

in this work we present a stellar structure model from the f（R）-gravity point of view capable of describing some classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This model is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium equation and a polytropic equation of state. We compare the results obtained with those found by Newtonian theory. it has been observed that in these systems, where high curvature regimes emerge,stellar structure equations undergo modifications. Despite the simplicity of this model, the results are satisfactory. The estimated values of pressure, density and temperature of the stars are within those determined by observations. This f（R）-gravity model has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosmology:theory stars:general massive brown dwarfs white dwarfs neutron

Prevalence of visual impairment and estimation of refractive errors among school children in Kakamega,Kenya

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international Journal of Ophthalmology(English edition) 2024年第5期17卷 932-939页

作者： isabel Signes-Soler Alfred ragot Sheilah Nangena Andrew Wekesa raúl Montalbán Llamusí Department of Optics and Optometry and Vision Sciences Universidat de ValènciaBurjassotValencia 46010Spain NGO Vision Without Borders(Visio Sense Fronteres VSF)Calpe 03710AlicanteSpain Masinde Muliro University of Science and Technology P.O Box 190-50100KakamegaKenya Clinica Baviera Alicante C/Ausóy Monzó 16Alicante 03006Spain

AiM:To investigate the prevalence of visual impairment(Vi)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community ***:The study was *** 3343 participants were included in the *** initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D *** inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVAimal(0.20 logMAR)and/or a VA with+2.00 D≥0.8 decimal(0.96 logMAR).RESULTS:The sample had a mean age of 10.92±2.13y(range 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to *** the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye *** estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total *** around 0.18%of the total sample had hyperopia value exceeding+1.75 *** astigmatism(cilin 0.21%(7/3343)of the *** Vi prevalence was 1.26%of the total *** our cases of Vi,76.2%could be attributed to uncorrected refractive *** was detected in 0.66%(22/3343)of the screened *** was no statistically significant correlation observed between age or gender and refractive ***:The primary cause of Vi is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error *** findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of Vi.

关键词： visual impairment refractive errors myopia amblyopia sustainable development goals

Four buildings and a flush:Lessons from degraded water quality and recommendations on building water management

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Environmental Science and Ecotechnology 2024年第2期18卷 104-113页

作者： Kyungyeon ra Caitlin Proctor Christian Ley Danielle Angert Yoorae Noh Tolulope Odimayomi Andrew J.Whelton Lyles School of Civil Engineering Purdue University550 Stadium Mall DriveWest LafayetteIN47907USA Agricultural and Biological Engineering Division of Environmental and Ecological EngineeringPurdue UniversityWest LafayetteIN47907USA Division of Environmental and Ecological Engineering Purdue UniversityWest LafayetteIN47907USA Civil and Environmental Engineering University of Colorado1111 Engineering DriveBoulderCO80309USA Civil Architectural and Environmental EngineeringUniversity of Texas301E E Dean Keeton StreetAustinTX78712USA Civil and Environmental Engineering Virginia Tech750 Drillfield DriveBlacksburgVA24061USA Lyles School of Civil Engineering Division of Environmental and Ecological EngineeringPurdue University550 Stadium Mall DriveWest LafayetteIN47907USA

A reduction in building occupancy can lead to stagnant water in plumbing,and the potential consequences for water quality have gained increasing *** investigate this,a study was conducted during the COViD-19 pandemic,focusing on water quality in four institutional *** of these buildings were old(>58 years)and large(>19,000 m2),while the other two were new(>13 years)and small(ignificant decreases in water usage in the small buildings,whereas usage remained unchanged in the large *** analysis found that residual chlorine was rarely detectable in cold/drinking water ***,the pH,dissolved oxygen,total organic carbon,and total cell count levels in the first draw of cold water samples were similar across all ***,the ranges of heavy metal concentrations in large buildings were greater than observed in small ***(Cu),lead(Pb),and manganese(Mn)sporadically exceeded drinking water limits at cold water fixtures,with maximum concentrations of 2.7 mg Cu L^(-1),45.4 mg Pb L^(-1),1.9 mg Mn L^(-1).Flushing the plumbing for 5 min resulted in detectable residual at fixtures in three buildings,but even after 125 min of flushing in largest and oldest building,no residual chlorine was detected at the fixture closest to the building's point of *** the pandemic,the building owner conducted fixture flushing,where one to a few fixtures were operated per visit in buildings with hundreds of fixtures and multiple ***,further research is needed to understand the fundamental processes that control faucet water quality from the service line to the *** the absence of this knowledge,building owners should create and use as-built drawings to develop flushing plans and conduct periodic water testing.

关键词： COViD-19 pandemic Stagnation Drinking water quality Flushing

Chi-square automatic interaction detection(CHAiD)analysis of the use of safety goggles and face masks as personal protective equipment(PPE)to protect against occupational biohazards

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Journal of Biosafety and Biosecurity

Journal of Biosafety and Biosecurity 2024年第2期6卷 125-133页

作者： raúl Aguilar-elena Juán JoséAgún-González Universidad internacional de Valencia ValenciaSpain

Background:This study represents the first Spanish investigation to rigorously evaluate compliance with the use of safety goggles and face masks as essential personal protective equipment(PPE)in companies with workplaces involving exposure to biological ***:This study aimed to examine the degree of use of face masks and safety goggles as personal protective equipment(PPE),the factors that influence their use,and the profile of workers exposed to occupational biological agents in Spanish companies in the health sector,farming sector,meat industry,waste treatment plants,food industry,and veterinary ***:We conducted a cross-sectional descriptive study involving 590 Spanish workers from 51 *** developed a 34-item questionnaire to assess workers’perception of risk related to exposure to biological agents in their *** the questions,three were designed to measure the degree of use of key protective equipment in sectors with biological agent exposure:protective gloves,safety goggles or face *** only analyzed safety goggles and face *** performed various statistical analyses,including Cronbach’s alpha,frequency of endorsement,content validity ratio using lawshe’s method,varimax rotation,the Kaiser-Meyer-Olkin test,and Bartlett’s sphericity test,to assess the internal consistency and reliability of the ***,we employed a chi-square automatic interaction detection(CHAiD)segmentation analysis,using workers’responses regarding their attitudes toward safety goggles and face mask usage as PPE for protection against biological risks,with demographic variables as independent ***:in the current study,CHAiD analysis revealed that workers exposed to group 2 biological agents used more safety goggles and face shields compared with workers exposed to other groups of biological ***,workers in laboratories and the food industry used face masks more than workers of other ***

关键词： PPE Safety googles and breath mask CHAiD Biological Agents Occupational Biosafety

Natural Convection of a Power-law Nanofluid in a Square Cavity with a Vertical Fin

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2091-2108页

作者： Amira M’hadbi Mohammed el Ganaoui Haïkel Ben Hamed Amenallah Guizani Khalid Chtaibi LERMAB Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTi Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law nanofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of nanofluids,composed of water and Al_(2)O_(3),TiO_(2),and Cu nanoparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the rayleigh number(ra=10^(4)-10^(6)),nanoparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).Streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing rayleigh number,regardless of the nanoparticle type or nanofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu nanoparticle volume fractions compared to Al₂O₃and TiO₂.Moreover,the average Nusselt numbers for power-law nanofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of rayleigh number ra owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning nanofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%nanoparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer nanofluid non-Newtonian fluid natural convection

Within-host models unravelling the dynamics of dengue reinfections

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infectious Disease Modelling 2024年第2期9卷 458-473页

作者： Vizda Anam Bruno V.Guerrero Akhil Kumar Srivastav Nico Stollenwerk Maíra Aguiar Basque Center for Applied Mathematics Basque CountrySpain Department of Mathematics and Statistics University of Basque CountryBasque CountrySpain ikerbasque Basque Foundation for ScienceBasque CountrySpain

Caused by four serotypes,dengue fever is a major public health concern *** modeling efforts have mostly focused on primary and heterologous secondary infections,assuming that lifelong immunity prevents reinfections by the same ***,recent findings challenge this assumption,prompting a reevaluation of dengue immunity *** this study,we develop a within-host modeling framework to explore different scenarios of dengue *** previous studies,we go beyond a deterministic framework,considering individual immunological *** deterministic and stochastic models are calibrated using empirical data on viral load and antibody(igM and igG)concentrations for all dengue serotypes,incorporating confidence intervals derived from stochastic *** good agreement between the mean of the stochastic realizations and the mean field solution for each model,our approach not only successfully captures primary and heterologous secondary infection dynamics facilitated by antibody-dependent enhancement(ADE)but also provides,for the first time,insights into homotypic reinfection *** study discusses the relevance of homotypic reinfections in dengue transmission at the population level,highlighting potential implications for disease prevention and control strategies.

关键词： infections immunity prevention

Prenatal Diagnosis of an Apically Located Congenital Left Ventricular Aneurysm: A rare Case

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Congenital Heart Disease 2024年第1期19卷 123-129页

作者： Yücel Kaya And Yavuz Hasan Berkan Sayal Büşra Tsakir Gökalp Kabacaoğlu Kadriye NilayÖzcan Department of Perinatology Antalya Education and Research HospitalUniversity of Health SciencesAntalyaTurkey Department of Perinatology Faculty of MedicineSüleyman Demirel UniversityIspartaTurkey

Congenital ventricular aneurysm is a very rare cardiac anomaly.A diagnosis can be made during the prenatal period using fetal *** study presents a very rare apically located left ventricular aneurysm case,and the relevant literature was reviewed and *** this case,a 35-year-old,gravida 2,parity 1 preg-nant woman at 24 weeks of gestation,displayed a wide aneurysmal image in the left ventricular apical wall on fetal *** was a 1.79 mm muscular ventricular septal defect at the apical region of the interven-tricular *** the course of the color Doppler ultrasonography examination,an aberrantﬁbrous band within the left ventricle and consequent turbulentﬂow during systole were *** baby,born via cesarean section at 37 weeks of gestation,is now in its postnatal seventh ***,during echocardiographic follow-ups,changes have been observed,including mild to moderate mitral insufﬁciency and a decrease in systolic *** theseﬁndings,the clinical condition remains *** is of great importance to use a multidis-ciplinary approach in managing these rare cases that could lead to potential adverse outcomes during the antena-tal or postnatal periods.

关键词： Heart aneurysm prenatal diagnosis echocardiography congenital heart defects left ventricle

Effectiveness of sensory integration therapy in children,focusing on Korean children:A systematic review and meta-analysis

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World Journal of Clinical Cases 2024年第7期12卷 1260-1271页

作者： Seri Oh Jong-Sik Jang A-ra Jeon Geonwoo Kim Mihwa Kwon Bahoe Cho Narae Lee Department of Occupational Therapy Kangwon National University Graduate SchoolSamcheok 25949South Korea Department of Occupational Therapy Kangwon National UniversitySamcheok 25949South Korea Department of Occupational Therapy Ju-Ju Children Development CenterNonsansi 32985Chungcheongnam-doSouth Korea Department of Occupation Therapy Suwon Women’s UniversityGyeonggi-do 16632South Korea Hijam Center for Development of Children Ochang 28117South Korea Department of Occupational Therapy U1 UniversityChung-cheong bukdo 25949South Korea

BACKGROUND Sensory integration intervention is highly related to the child's effective interaction with the environment and the child's ***,various sensory integration interventions are being applied,but research methodological problems are arising due to unsystematic *** study aims to present the optimal intervention protocol by presenting scientific standards for sensory integration intervention through *** To prove the effectiveness of sensory integration therapy,examine the latest trend of sensory integration studies in Korea,and provide clinical evidence for sensory integration *** The database of Korean search engines,including RiSS,KiSS,and DBpia,was used to search for related literature published from 2001 to October *** keywords,“Children”,“Sensory integration”,“integrated sensory”,“Sensorymotor”,and“Sensory stimulation”were used in this ***,a meta-analysis was conducted on 24 selected studiesRiSS,KiSS,and DBpia,was used to search for related literature published from 2001 to October *** keywords,“Children”,“Sensory integration”,“integrated sensory”,“Sensorymotor”,and“Sensory stimulation”were used in this ***,a meta-analysis was conducted on 24 selected *** Sensory integration intervention has been proven effective in children with cerebral palsy,autism spectrum disorder,attention deficit/hyperactivity disorder,developmental disorder,and intellectual disability in relation to the diagnosis of *** sensory integration therapies,1:1 individual treatment with a therapist or a therapy session lasting for 40 min was most *** terms of dependent variables,sensory integration therapy effectively promoted social skills,adaptive behavior,sensory processing,and gross motor and fine motor *** The results of this study may be used as therapeutic evidence for sensory integration intervention in the clinical field of occupational therapy for

关键词： Children Meta-analysis Occupational therapy Sensory integration Sensory processing Social skills