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Increasing power plant efficiency with clustering methods and Variable Importance Index assessment

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Energy and AI 2021年第3期5卷 82-90页

作者： j.ssica Duarte lara Werncke Vieira Augusto Delavald Marques Paulo Smith Schneider guilherme Pumi Taiane Schaedler Prass Department of Mechanical Engineering Federal University of Rio Grande do SulPorto AlegreBrazil graduate Program in Statistics Federal University of Rio Grande do SulPorto AlegreBrazil

Power plant performance can decrease along with its life span,and move away from the design and commissioning *** issues,operational practices,market restrictions,and financial objectives may lead to that behavior,and the knowledge of appropriate actions could support the system to retake its original operational *** paper applies unsupervised machine learning techniques to identify operating patterns based on the power plant’s historical data which leads to the identification of appropriate steam generator efficiency *** selected operational variables are evaluated in respect to their impact on the system performance,quantified by the Variable Importance *** metric is proposed to identify the variables among a much wide set of monitored data whose variation impacts the overall power plant operation,and should be controlled with more *** Component Analysis(PCA)and k-means++clustering techniques are used to identify suitable operational conditions from a one-year-long data set with 27 recorded variables from a steam generator of a 360MW thermal power *** adequate number of clusters is identified by the average Silhouette coefficient and the Variable Importance Index sorts nine variables as the most relevant ones,to finally group recommended settings to achieve the target *** show performance gains in respect to the average historical values of 73.5%and the lowest efficiency condition records of 68%,to the target steam generator efficiency of 76%.

关键词： Thermal power plant performance enhancement Operating patterns identification K-means clustering Principal component analysis Unsupervised machine learning

Synthesis and characterization of carbon-TiO2-CeO2 composites and their applications in phenol degradation

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journal of Rare Earths 2017年第6期35卷 551-558页

作者： Y.lara-López g.garcía-Rosales j.jiménez-Becerril Technological Institute of Toluca Posgrade and Research Division Ex-Rancho La Virgen S/N C.P. 50120 Metepec Mexico National Institute for NuclearResearch Chemistry Department. Carretera Mexico-Toluca S/N la Marquesa Ocoyoacac C.P. 52750 Mexico

The objective of this work was to synthesize particles of titanium oxide and cerium oxide supported on carbon, which was obtained through the pyrolysis of orange peel. The materials were characterized using scanning electron microscopy, X-ray diffraction, infrared spectroscopy, and the specific surface area from Brunauer-Emmett-Teller method. The photocatalytic properties of the synthesized materials were determined by the degradation of phenol in 30 mg/L aqueous solutions. TiO2-CeO2 particles were obtained with an average spherical size of 57 nm and were supported on the carbon surface; this material presented a specific surface area of 296 m2/g and degrades -40% of phenol after 240 min of UV irradiation.

关键词： phenol photocatalytic spherical pyrolysis irradiation Teller Brunauer ceria orange cerium

Type 1 diabetes and associated autoimmune diseases

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World journal of Diabetes 2020年第11期11卷 527-539页

作者： lara Frommer george j Kahaly Department of Medicine I Johannes Gutenberg Medical CenterMainz 55131Germany

BACKgROUND Common autoimmune diseases(AID)tend to occur together in the same individual and *** 1 diabetes(T1D)is caused by an autoimmuneinduced inflammatory destruction of the pancreatic tissue and clusters with several other *** To compare the demographic,clinical,and serological features of patients with single T1D vs those with T1D and associated *** From October 1999 to February 2020,a total of 665 patients with T1D and their first-degree relatives were *** Compared to patients with isolated T1D,those with T1D+AID were older and had a higher female:male *** patient age and age at disease onset were higher in T1D+AID vs T1D *** average time interval between T1D onset and the onset of a second glandular AID was markedly shorter than the time interval between T1D and the occurrence of a non-endocrine AID.T1Dspecific autoantibodies were more frequent in patients with T1D+AID and relatives vs those with T1D ***,the prevalence of AID and autoantibodies against various tissues were found to be higher in relatives of patients with T1D only compared to relatives of patients with T1D+*** Annual serological and subsequent functional screening for AID in patients with T1D and their first-degree relatives is recommended.

关键词： Type 1 diabetes Autoimmunity Serology Antibodies Autoimmune endocrine diseases Autoimmune non-endocrine disorders

Immunoglobulin Transport during gestation in Domestic Animals and Humans—A Review

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Open journal of Animal Sciences 2014年第5期4卷 323-336页

作者： j.ssica Borghesi lara Carolina Mario Marcio Nogueira Rodrigues Phelipe Oliveira Favaron Maria Angelica Miglino Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo S&#227o Paulo Brasil

Maternal immunity is the main early defense against infectious agents in newborns. Immunoglobulin g (Igg) is indispensable for immune defense against infectious agents. Igg is transported through either the colostrum or the placenta. Immunoglobulins are antibodies, and the five different classes of these antibodies are Igg, IgA, IgM, IgD and IgE. Through their biological function of binding antigens, antibodies facilitate the removal of antigens from the body. The placenta is a temporary maternal-fetal organ, whose principal function is to allow the controlled exchange of metabolites between mother and embryo/fetus during gestation. The placenta types in different species are classified by the number of membranes separating the maternal and fetal blood circulation. Humans, lagomorphs and rodents have hemochorial placentas, which require a receptor for Igg transfer. In other animals, such as horse and pig (epitheliochorial placenta), ruminants (synepitheliochorial placenta) and carnivores (endotheliochorial placenta), antibodies are transferred via the colostrum and absorbed by passive diffusion. This review covers immunoglobulin transport in several types of placentas.

关键词： Colostrum Immunoglobulin Mammalian Fetal Membranes Placenta

Rotational stability of plate haptic toric intraocular lenses after combined 25-gauge vitrectomy and cataract surgery

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International journal of Ophthalmology(English edition) 2023年第8期16卷 1231-1236页

作者： lara Buhl julian Langer Stefan Kassumeh Thomas C.Kreutzer Wolfgang j.Mayer Siegfried g.Priglinger Department of Ophthalmology University HospitalLMU MunichMunich 80336Germany

AIM:To evaluate the postoperative intraocular lens(IOL)rotational stability and residual refractive astigmatism following combined 25-gauge vitrectomy and cataract surgery with implantation of a plate haptic toric ***:In this retrospective case series,32 eyes of 32 patients underwent a combined 25-gauge vitrectomy and phacoemulsification for vitreoretinal diseases and cataract with regular corneal astigmatism of at least 1 diopter(D).A plate haptic toric IOL(AT Torbi 709M,Carl Zeiss Meditec Ag)was implanted in all *** outcome measures were rotational stability and refractive astigmatism up to 6mo postoperatively as well as the best corrected visual acuity(BCVA).RESULTS:Preoperative refractive astigmatism was 2.14±1.17 D,which was significantly reduced to 0.77±0.37 D six to eight weeks postoperatively and remained stable throughout the observation period(0.67±0.44 D at three months and 0.75±0.25 D at six months;for all groups:Pgnificantly from 0.36±0.33 logMAR preoperatively to 0.10±0.15 logMAR following surgery(P=0.02).Mean IOL axis deviation from the target axis was 3.4°±2.9°after six to eight weeks and significantly decreased over time(2.4°±2.6°six months after surgery;P=0.04).In one patient IOL,re-alignment was ***:Corneal astigmatism is significantly reduced following combined 25-gauge vitrectomy and cataract *** plate haptic toric IOL position and axis remain stable during the observation period of six months.

关键词： combined phaco-vitrectomy toric intraocular lens rotational stability corneal astigmatism cataract vitreoretinal disease

Differential effects of two dominant plant species on community structure and invasibility in an old-field ecosystem

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journal of Plant Ecology 2011年第3期4卷 123-131页

作者： lara Souza jake F.Weltzin Nathan j.Sanders Department of Ecology and Evolutionary Biology University of Tennessee1416 Circle DriveKnoxvilleTN 37996USA USA National Phenology Network National Coordinating Office1955 East 6th StreetTucsonAZ 85719USA

Aims In this study,we examined the effects of Solidago altissima(hereafter Solidago)and two species in the genus Verbesina,Verbesina virginica and Verbesina occidentalis(hereafter Verbesina),on the structure of an old-field plant community and establishment by an invasive plant species,Lespedeza cuneata(hereafter Lespedeza).Methods We removed Solidago,Verbesina and both Solidago and Verbesina from 4m^(-2)plots in an intact old-field community during two growing *** then quantified the effects of these removals on richness,evenness,diversity and composition of the subdominant plant *** also measured the total aboveground biomass and the aboveground biomass of the subdominant *** assess how these removals affected establishment by Lespedeza,we planted 20 seeds in each plot and tracked seedling emergence and survival for one growing *** Findings Subdominant community evenness and Shannon diversity were higher in plots from which Solidago and Verbesina were removed relative to control ***,there were no effects of dominant species removal on species richness or composition of the subdominant *** aboveground biomass was not affected by dominant species removal,suggesting that the community of subdominant species exhibited *** fact,subdominant community biomass was greater when Solidago,but not Verbesina,was *** availability was also greater in plots where Solidago was removed relative to control plots throughout the growing *** addition,removal of dominant species,in particular Solidago,indirectly reduced the emergence,but not survival,of Lespedeza seedlings by directly promoting subdominant community *** together,our results suggest that dominant old-field plant species affect subdominant community structure and indirectly promote establishment by Lespedeza.

关键词： compensation establishment invasive Lespedeza cuneata Solidago Verbesina

The “PAWPER-on-a-page”: Increasing global access to a low-cost weight estimation system

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World journal of Emergency Medicine 2019年第2期10卷 101-108页

作者： Mike Wells lara Nicole goldstein Division of Emergency Medicine Faculty of Health Sciences University of the Witwatersrand

BACKgROUND: The PAWPER tape is one of the most accurate weight estimation systems available today, but international access to the tape is limited because it has no commercial distribution. For this reason, the "PAWPER-on-a-page" concept was devised: downloadable image fi les that allow users to print and assemble their own tapes. However, the feasibility of this method is dependent on users being able to produce accurate tapes. This study was devised to determine whether untrained participants could print and assemble the "PAWPER-on-a-page" easily and ***: Doctor and nurse volunteers downloaded the "PAWPER-on-a-page" and "PAWPER XL-on-a-page" image files and printed copies on a home-printer and also at a commercial printer. One copy of each tape was then assembled according to instructions from an online video. The accuracy of printing and assembly, the time taken for assembly and the cost were then ***: There were 32 participants. The median time for assembly was 8 minutes 19 seconds and 7 minutes 31 seconds for the "PAWPER-on-a-page" and "PAWPER XL-on-a-page" respectively, with a median cost of USD 0.09 and USD 1.00 respectively. For the assembled tapes, 71.9% of the "PAWPER-on-a-page" tapes and 65.6% of the "PAWPER XL-on-a-page" achieved the required accuracy of 0.2%. Printing errors, related to scaling, were common, but easily ***: The "PAWPER-on-a-page" system can be easily, quickly, affordably and accurately printed and assembled by end users. Stringent double checking of the printed and fully assembled tapes is essential to ensure accuracy.

关键词： PAWPER tape Weight estimation Paediatric emergency care

Use of improved cold-finger technique to assess effects of basicity on heat transfer through solidified mold flux

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journal of Iron and Steel Research International 2019年第4期26卷 393-402页

作者： Karina lara Santos Assis Petrus Christiaan Pistorius Department of Materials Science and Engineering Center for Iron and Steelmaking ResearchCarnegie Mellon UniversityPittsburgh 15213PAUSA

Cold-finger measurements were used to estimate the contact resistance and average thermal conductivity of mold flux films solidified on a water-cooled copper *** industrial mold fluxes,with basicities from low to high,were *** steady-state rate of convective heat transfer between the solid film and liquid flux was compared with calculations based on natural convection correlations;the comparison indicates that the surface of the solid film(in contact with molten flux)is approximately at its solidus *** roughness of the mold flux film in contact with copper was larger for films grown from higher-temperature mold flux and for higher-basicity mold *** glassy(low-basicity)film had an estimated thermal conductivity of 1.1 W/(m K).The crystalline or partially crystalline films had higher estimated thermal conductivities of 2.2-3.2 W/(m K).The measured values of thermal resistance were extrapolated to typical mold flux film thicknesses for industrial conditions;the extrapolations confirmed that the high contact resistance of higher-basicity mold fluxes can yield higher thermal resistances than the low-basicity *** morphology of the rough interface of higherbasicity mold flux films that gives the higher contact resistance is consistent with that observed in previous work and appears not to be directly related to crystallization.

关键词： Mold flux Heat transfer Conduction Contact resistance-Cold-finger technique

An experimental study on the conversion between IFPUg and UCP functional size measurement units

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journal of Zhejiang University-Science C(Computers and Electronics) 2014年第3期15卷 161-173页

作者： juan j.CUADRADO-gALLEgO Alain ABRAN Pablo RODRígUEZ-SORIA Miguel A.lara Ecole de Technologie Supérieure-ETS 1100 Notre-Dame Ouest Computer Science Department University of Alcala

The use of functional size measurement(FSM) methods in software development organizations is growing during the years. Also, object oriented(OO) techniques have become quite a standard to design the software and, in particular, Use Cases is one of the most used techniques to specify functional requirements. Main FSM methods do not include specific rules to measure the software functionality from its Use Cases analysis. To deal with this issue some other methods like Kramer's functional measurement method have been developed. Therefore, one of the main issues for those organizations willing to use OO functional measurement method in order to facilitate the use cases count procedure is how to convert their portfolio functional size from the previously adopted FSM method towards the new method. The objective of this research is to find a statistical relationship for converting the software functional size units measured by the International Function Point Users group(IFPUg) function point analysis(FPA) method into Kramer-Smith's use cases points(UCP) method and vice versa. Methodologies for a correct data gathering are proposed and results obtained are analyzed to draw the linear and non-linear equations for this correlation. Finally, a conversion factor and corresponding conversion intervals are given to establish the statistical relationship.

关键词： Software engineering Requirements analysis Functional size measurement Use cases analysis Object oriented Function point analysis Use cases points