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A robust model-free controller for a three-phase grid-connected photovoltaic system based on ultra-local model
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作者 Ahsene Boubakir Sid-Ahmed Touil +1 位作者 Salim Labiod Nasserdine Boudjerda 《Protection and Control of Modern Power Systems》 2021年第1期538-550,共13页
In this paper, a robust model-free controller for a grid-connected photovoltaic (PV) system is designed. The system consists of a PV generator connected to a three-phase grid by a DC/AC converter. The control objectiv... In this paper, a robust model-free controller for a grid-connected photovoltaic (PV) system is designed. The system consists of a PV generator connected to a three-phase grid by a DC/AC converter. The control objectives of the overall system are to extract maximum power from the PV source, to control reactive power exchange and to improve the quality of the current injected into the grid. The model-free control technique is based on the use of an ultra-local model instead of the dynamic model of the overall system. The local model is continuously updated based on a numerical differentiator using only the input–output behavior of the controlled system. The model-free controller consists of a classical feedback controller and a compensator for the effects of internal parameter changes and external disturbances. Simulation results illustrate the efficiency of the controller for grid-connected PV systems. 展开更多
关键词 Photovoltaic system Maximum power point Model-free control Ultra-local model Numerical differentiator
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粉煤灰与水泥浆体间界面的形貌特征 被引量:47
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作者 王培铭 陈志源 ScholzH 《硅酸盐学报》 EI CAS CSCD 北大核心 1997年第4期474-479,共6页
用SEM和EDS研究了粉煤灰掺入水泥后与水泥浆体间所形成界面的形貌特征。结果表明,在水泥水化初期,粉煤灰表面呈三种状态:(1)被CSH单层膜包裹;(2)被CHCSH双层膜包裹;(3)嵌入块状CH晶体内。在水泥水化后期... 用SEM和EDS研究了粉煤灰掺入水泥后与水泥浆体间所形成界面的形貌特征。结果表明,在水泥水化初期,粉煤灰表面呈三种状态:(1)被CSH单层膜包裹;(2)被CHCSH双层膜包裹;(3)嵌入块状CH晶体内。在水泥水化后期,粉煤灰颗粒表面层已完全与水泥水化产物发生反应,且形成若干层反应物,呈致密的粒状或环状凝胶体。 展开更多
关键词 粉煤灰 水泥 浆体 界面 形貌
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Modeling habitat suitability and utilization of the last surviving populations of fallow deer(Dama dama Linnaeus,1758)
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作者 YasinÜnal ÖzdemirŞentürk +3 位作者 Ali Kavgaci Halil Süel Serkan Gülsoy Idris Oğurlu 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第2期721-730,共10页
DüzlerçamıWildlife Reserve Area(WRA)is the last natural habitat of fallow deer(Dama dama)in the world.Fallow deer is native to Turkey,however,its geographical range is currently confined to Düzlerç... DüzlerçamıWildlife Reserve Area(WRA)is the last natural habitat of fallow deer(Dama dama)in the world.Fallow deer is native to Turkey,however,its geographical range is currently confined to DüzlerçamıWRA,Antalya.To date,a detailed habitat investigation of fallow deer dis-tribution has not been conducted.This study is vital for the last surviving populations of fallow deer in Turkey.There-fore,we studied the habitat suitability and utilization of fal-low deer in the DüzlerçamıWRA.Vegetation and wildlife inventory was surveyed across a total of 304 sample areas between 2015 and 2017.Plant species were recorded accord-ing to the Braun-Blanquet method and wildlife surveys were based on footprints,feces,and other signs of fallow deer.Classification and regression tree techniques,as well as MAXENT,were used to model vegetation and fallow deer habitat.Topographic position index,terrain ruggedness index,roughness index,elevation,and bedrock formation were also calculated and included in the models.Based on our results,we drafted a habitat protection map for fallow deer.To ensure sustainability of habitats where populations of fallow deer are found in Turkey,we developed recommen-dations such as closuring human access of the 1st-degree Protection Area and reintroduction of the species to other potential habitats. 展开更多
关键词 UNGULATES Fallow deer MAXENT Wildlife reserve area Düzlerçamı Antalya TURKEY
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Do Relationships Matter in Export Performance Enhancement? Evidences From Moroccan SMEs
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作者 SaifAllah Allouani Houcine Berbou 《Chinese Business Review》 2012年第4期383-393,共11页
关键词 出口企业 摩洛哥 中小企业 增强物 证据 利巴韦林 市场因素 中小型企业
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The Rheological and Extrusion Behaviour of Blends Based on Phenolphthalein Poly(ether-ether-sulfone)and Thermotropic Liquid Crystalline Polymer
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作者 DI Ying-wei D'AMORE Alberto +3 位作者 NICOLAIS Luigi ACIERNO Domenico NOBILE Rossella LI Bin-yao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第3期93-101,共9页
IntroductionInthelasttwodecades,particularatentionhasbeendevotedtousingthethermotropicliquidcrystalinepolyme... IntroductionInthelasttwodecades,particularatentionhasbeendevotedtousingthethermotropicliquidcrystalinepolymers(TLCP)asareinfo... 展开更多
关键词 Phenolphthalein poly(ether ether sulfone) Thermotropic liquid crystalline polymer BLEND Rheology
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疑似阿尔茨海默病患者不自觉认知功能缺陷(认知功能病感失认)的对照研究
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作者 Barrett A.M. Eslinger P.J. +2 位作者 Ballentine N.H. Heilman K.M. 邓剑平 《世界核心医学期刊文摘(神经病学分册)》 2005年第7期50-50,共1页
Objective: To develop a quantitative method of assessing cognitive anosognosia in six cognitive and two noncognitive domains.Methods: Control (n =32) and prob able Alzheimer disease(pAD) (n = 14) subjects self-estimat... Objective: To develop a quantitative method of assessing cognitive anosognosia in six cognitive and two noncognitive domains.Methods: Control (n =32) and prob able Alzheimer disease(pAD) (n = 14) subjects self-estimated memory, attention, generative behavior, naming, visuospatial skill, limb praxis, mood,and uncorrec ted vision, both before and after these abilities were assessed. Based on this e stimate and their performance the authors calculated an anosognosia ratio (AR) b y dividing the difference between estimated and actual performance by an estimat ed and actual performance sum. With perfect awareness,AR = 0. Overestimating abi lities would yield a positive AR (≤1); underestimation would yield a negative A R (≥-1). Results: Relative to controls, pAD subjects demonstrated anosognosia. Pre-testing (off-line), pAD subjects overestimated their visuospatial skill; p ost-testing (on-line), pAD subjects overestimated their memory. Control subjec ts also made selfrating errors, underestimating their attention pre-testing and overestimating limb praxis and vision post-testing. Conclusions:This anosognos ia assessment method may allow more detailed examination of distorted self-awar eness. These results suggest that screening for anosognosia in probable Alzheime r disease (pAD) should include self-estimates of visuospatial function, and tha t, in pAD, it may be useful to assess anosognosia for amnesia both before and af ter memory testing. 展开更多
关键词 认知功能 阿尔茨海默病 失认 病感 记忆测试 视觉空间 过高估计 矫正视力 不自觉 自我评价
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侵入性曲菌病与慢性阻塞性肺疾病
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作者 Alejandro Rodriguez +1 位作者 胡志明 《世界医学杂志》 2002年第1期33-37,共5页
近些年,由于免疫抑制患者人数的不断增加,侵入性肺曲菌病(invasive pulmonary aspergillosis,IPA)的发病率也在上升,关于慢性阻塞性肺疾病(COPD)并伴有IPA的患者的病例报告也越来越多,在免疫抑制人群中,临床上的高度怀疑可提高... 近些年,由于免疫抑制患者人数的不断增加,侵入性肺曲菌病(invasive pulmonary aspergillosis,IPA)的发病率也在上升,关于慢性阻塞性肺疾病(COPD)并伴有IPA的患者的病例报告也越来越多,在免疫抑制人群中,临床上的高度怀疑可提高早期诊断水平,成功率为30%-50%,然而,COPD患者的死亡率几近100%,治疗上的延迟与临床上怀疑程度不够有关,是导致死亡的主要因素。而且,在呼吸系统的标本中发现其他的病原性微生物可能是另外一个导致延迟治疗的因素,要牢记的重要点是,COPD患者具有发生IPA的高危险性,持续的肺部炎性浸润或临床恶警示医生:患者可能为IPA,总之,我们同其他作者一样,同样疾病控制中心提出的指导原则,即应将COPD患者列为高危患者。 展开更多
关键词 侵入性肺曲菌病 慢性阻塞性肺疾病 类固醇 诊断 IPA COPD
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EIS Studies of Anionic Surfactants Inhibiting Effect of AI-2017 Corrosion in HCI Aqueous Solutions
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作者 R. Mehdaoui A. Khadraoui +2 位作者 A. Khelifa K. Chouchane A. Zerrouk 《材料科学与工程(中英文A版)》 2017年第5期258-270,共13页
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Evaluation and comparison of CMIP6 models and MERRA-2 reanalysis AOD against Satellite observations from 2000 to 2014 over China
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作者 Md.Arfan Ali Muhammad Bilal +9 位作者 Yu Wang Zhongfeng Qiu Janet E.Nichol Gerrit de Leeuw Song Ke Alaa M.hawish Mansour Almazroui Usman Mazhar Birhanu Asmerom Habtemicheal M.Nazrul Islam 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第2期165-185,共21页
Rapid industrialization and urbanization along with a growing population are contributing significantly to air pollution in China.Evaluation of long-term aerosol optical depth(AOD)data from models and reanalysis,can g... Rapid industrialization and urbanization along with a growing population are contributing significantly to air pollution in China.Evaluation of long-term aerosol optical depth(AOD)data from models and reanalysis,can greatly promote understanding of spatiotemporal variations in air pollution in China.To do this,AOD(550 nm)values from 2000 to 2014 were obtained from the Coupled Model Intercomparison Project(CIMP6),the second version of Modern-Era Retrospective analysis for Research,and Applications(MERRA-2),and the Moderate Resolution Imaging Spectroradiometer(MODIS;flying on the Terra satellite)combined Dark Target and Deep Blue(DTB)aerosol product.We used the TerraMODIS DTB AOD(hereafter MODIS DTB AOD)as a standard to evaluate CMIP6 Ensemble AOD(hereafter CMIP6 AOD)and MERRA-2 reanalysis AOD(hereafter MERRA-2 AOD).Results show better correlations and smaller errors between MERRA-2 and MODIS DTB AOD,than between CMIP6 and MODIS DTB AOD,in most regions of China,at both annual and seasonal scales.However,significant under-and over-estimations in the MERRA-2 and CMIP6 AOD were also observed relative to MODIS DTB AOD.The long-term(2000-2014)MODIS DTB AOD distributions show the highest AOD over the North China Plain(0.71)followed by Central China(0.69),Yangtse River Delta(0.67),Sichuan Basin(0.64),and Pearl River Delta(0.54)regions.The lowest AOD values were recorded over the Tibetan Plateau(0.13±0.01)followed by Qinghai(0.19±0.03)and the Gobi Desert(0.21±0.03).Large amounts of sand and dust particles emitted from natural sources(the Taklamakan and Gobi Deserts)may result in higher AOD in spring compared to summer,autumn,and winter.Trends were also calculated for 2000-2005,for2006-2010(when China introduced strict air pollution control policies during the 11 th Five Year Plan or FYP),and for 2011-2014(during the 12 th FYP).An increasing trend in MODIS DTB AOD was observed throughout the country during 2000-2014.The uncontrolled industrialization,urbanization,and rapid economic development that mostly occurred from 2000 to 2005 probably contributed to the overall increase in AOD.Finally,China’s air pollution control policies helped to reduce AOD in most regions of the country;this was more evident during the 12 th FYP period(2011-2014)than during the 11 th FYP period(2006-2010).Therefore this study strongly advises the authority to retain or extend these policies in the future for improving air quality. 展开更多
关键词 Aerosol Optical Depth Air pollution MERRA-2 MODIS Air quality
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Metagenomic analysis to determine the characteristics of antibiotic resistance genes in typical antibiotic-contaminated sediments 被引量:1
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作者 Han Yang Mu Xu +3 位作者 Liqing Wang Xianyun Wang Erik Jeppesen Wei Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第6期12-25,共14页
Comprehensive studies of the effects of various physical and chemical variables(including heavymetals),antibiotics,and microorganisms in the environment on antibiotic resistance genes are rare.We collected sediment sa... Comprehensive studies of the effects of various physical and chemical variables(including heavymetals),antibiotics,and microorganisms in the environment on antibiotic resistance genes are rare.We collected sediment samples from the Shatian Lake aquaculture area and surrounding lakes and rivers located in Shanghai,China.The spatial distribution of sediment ARGs was assessed by metagenomic analysis that revealed 26 ARG types(510 subtypes),dominated by Multidrug,β-lactam,Aminoglycoside,Glycopeptides,Fluoroquinolone,and Tetracyline.Redundancy discriminant analysis indicated that antibiotics(SAs and MLs)in the aqueous environment and sediment along with water TN and TP were the key variables affecting the abundance distribution of total ARGs.However,the main environmental drivers and key influences differed among the different ARGs.For total ARGs,the environmental subtypes affecting their structural composition and distribution characteristics were mainly antibiotic residues.Procrustes analysis showed a significant correlation between ARGs and microbial communities in the sediment in the survey area.Network analysis revealed that most of the target ARGs were significantly and positively correlated with microorganisms,and a small number of ARGs(e.g.,rpoB,mdtC,and efpA)were highly significantly and positively correlated with microorganisms(e.g.,Knoellia,Tetrasphaera,and Gem-matirosa).Potential hosts for the major ARGs included Actinobacteria,Proteobacteria,and Gemmatimonadetes.Our study provides new insight and a comprehensive assessment of the distribution and abundance of ARGs and the drivers of ARG occurrence and transmission. 展开更多
关键词 Metagenomic analysis Antibiotic resistance genes Environmental drivers SEDIMENTS Shatian Lake
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ChemFET gas nanosensor arrays with alignment windows for assembly of single nanowires
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作者 Ondřej Chmela Imrich Gablech +2 位作者 Jakub Sadílek Jan Brodský Stella Vallejos 《Nano Research》 SCIE EI CSCD 2023年第7期10234-10244,共11页
This work focuses on the fabrication and characterization of Chemical Field-Effect Transistor(ChemFET)gas nanosensor arrays based on single nanowire(SNW).The fabrication processes include micro and nanofabrication tec... This work focuses on the fabrication and characterization of Chemical Field-Effect Transistor(ChemFET)gas nanosensor arrays based on single nanowire(SNW).The fabrication processes include micro and nanofabrication techniques enabled by a combination of ultraviolet(UV)and e-beam lithography to build the ChemFET structure.Results show the integration and connection of SNWs across the multiple pairs of nanoelectrodes in the ChemFET by dielectrophoresis process(DEP)thanks to the incorporation of alignment windows(200-300 nm)adapted to the diameter of the NWs.Measurements of the SNW ChemFET array's output and transfer characteristics prove the influence of gate bias on the drain current regulation.Tests upon hydrogen(H_(2))and nitrogen dioxide(NO_(2))as analyte models of reducing and oxidizing gases show the ChemFET sensing functionality.Moreover,results demonstrate better response characteristics to H_(2)when the ChemFET operates in the subthreshold regime.The design concepts and methods proposed for fabricating the SNW-based ChemFET arrays are versatile,reproducible,and most likely adaptable to other systems where SNW arrays are required. 展开更多
关键词 Chemical Field-Effect Transistor(ChemFET)nanosensors NANOWIRES NANOELECTRODES gas sensors
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Exploring the potential impact of nutritionally actionable genetic polymorphisms on idiopathic male infertility:a review of current evidence 被引量:3
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作者 Sinda Mahbouli Charlotte Dupont +2 位作者 Yaelle Elfassy Eric Lameignere Rachel Levy 《Asian Journal of Andrology》 SCIE CAS CSCD 2021年第5期441-449,共9页
Infertility affects about 15%of the world's population.In 40%-50%of infertile couples,a male factor underlies the problem,but in about 50%of these cases,the etiology of male infertility remains unexplained.Some cl... Infertility affects about 15%of the world's population.In 40%-50%of infertile couples,a male factor underlies the problem,but in about 50%of these cases,the etiology of male infertility remains unexplained.Some clinical data show that lifestyle interventions may contribute to male reproductive health.Cessation of unhealthy habits is suggested for preserving male fertility;there is growing evidence that most preexisting comorbidities,such as obesity and metabolic syndrome,are highly likely to have an impact on male fertility.The analysis of genetic polymorphisms implicated in metabolic activity represents one of the most exciting areas in the study of genetic causes of male infertility.Although these polymorphisms are not directly connected with male infertility,they may have a role in specific conditions associated with it,that is,metabolic disorders and oxidative stress pathway genes that are potentially associated with an increased risk of male infertility due to DNA and cell membrane damage.Some studies have examined the impact of individual genetic differences and gene-diet interactions on male infertility,but their results have not been synthesized.We review the current research to identify genetic variants that could be tested to improve the chances of conceiving spontaneously through personalized diet and/or oral vitamin and mineral supplementation,by examining the science of genetic modifiers of dietary factors that affect nutritional status and male fertility. 展开更多
关键词 energy metabolism genetic polymorphisms idiopathic male infertility lifestyle factors NUTRITION oxidative stress semen quality
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Self-powered smart patch for sweatconductivity monitoring 被引量:4
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作者 Laura Ortega Anna Llorella +1 位作者 Juan Pablo Esquivel Neus Sabate 《Microsystems & Nanoengineering》 EI CSCD 2019年第1期672-681,共10页
A self-powered skin patch for the measurement of sweat conductivity is presented.The key component of the patch consists of a paper battery that is activated upon absorption of sweat.This body fluid acts as the batter... A self-powered skin patch for the measurement of sweat conductivity is presented.The key component of the patch consists of a paper battery that is activated upon absorption of sweat.This body fluid acts as the battery electrolyte,the conductivity of which has a direct impact on the battery-generated output power and voltage.This particular behaviour enables the operation of a very simple and robust conductivity sensor in direct current mode without needing an external power source.The device presented in this paper takes advantage of this new measurement method to develop a sweat patch for screening cystic fibrosis that operates with an extremely simple electronic circuit that minimizes its cost and environmental impact.The patch provides an unambiguous digital result that can be read in an electrochromic display and yields 95%sensitivity and 100%specificity when tested with artificial eccrine perspiration samples. 展开更多
关键词 BATTERY CONDUCTIVITY PATCH
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Optimization Studies of Porous Carbon Preparation from Oil Shale Using Response Surface Methodology and Its Application for Phenol Adsorption
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作者 MANSOURI Said MAJDOUBI Hicham +6 位作者 HADDAJI Younesse TAMRAOUI Youssef ELACHABY Mounir MANOUN Bouchaib ABOURRICHE Abdelkrim HANNACHE Hassan OUMAM Mina 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2020年第6期1339-1347,共9页
This paper discusses the elaboration of adsorbents from oil shale.The experimental designs a response surface methodology(RSM),which has been applied to optimize the significant preparation factors,such as tempera-tur... This paper discusses the elaboration of adsorbents from oil shale.The experimental designs a response surface methodology(RSM),which has been applied to optimize the significant preparation factors,such as tempera-ture,time,and the activating agent percentage.The results obtained from central composite design(CCD)revealed that the interaction between the factors was significant for the maximum quantity of adsorption(response).Planned results have shown that a maximum quantity of adsorption for methylene blue is 65 mg/g,which could be achieved with a temperature of 275℃over 2 h and a percentage of the activating agent of 45%.The predicted values agreed with the experimental finding,with a determination coefficient(R2)of 0.96.The model has been validated by experi-ments after conditions optimization.The new material(RHO)was characterized by cation exchange capacity,zero charge pH,surface functions,X-ray fluorescence,specific surface area,and electron microscopy analysis.Phenol adsorption was determined using Langmuir,Freundlich and Temkin,which were used to describe the adsorption iso-therms.The adsorption capacity of the material was about 263 mg/g,and the kinetic studies showed rapid adsorption. 展开更多
关键词 Oil shale Activated carbon ADSORPTION Activation process Response surface methodology
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