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Petroleum Science 2018年第2期15卷 421-431页

作者： Claudio Benevenuto de Campos Lima Pedro Esteves Aranha jose francisco tebaldi de castro Gilson Brito Alves Lima Augusto Borella Hougaz Felipe de Souza Terra Petrobras department of Production Engineering Federal Fluminense University

In order to avoid mistakes and to save a great deal of time in analysis, an innovative methodology was developed that can analyze the well operations and rig characteristics involved to define the best emergency disconnect sequence （EDS） available. A solution was developed based on the characteristics of the rigs and blowout preventers （BOPs）, and six variables were considered that directly affect the choice of EDS. All possible combinations of 64 scenarios were analyzed, and the priority of choice of the EDS was defined empirically. This paper presents an approach to EDS risk management and examples of exposure time （time without riser safety margin and shear capability） for the same well, which can be lowered from 13% to 0.1%. The impact of this reduction is related to the ability of the BOP to cut some of the heavy casings, in addition to improved availability of EDS modes. This implementation opened up many possibilities for the performance of risk exposure analysis, enabling comparison of several BOP configurations of contracted rigs and selection of the best options. This innovative approach allowed a better management of the rig schedules, prioritizing safety aspects and making it possible to allocate the fleet in a systematic way.

关键词： Well safety Safety barriers Emergency disconnect sequence (EDS) Well control Kick Well design

An overview on nucleation theories and models

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Journal of Rare Earths 2019年第10期37卷 1015-1022页

作者： Marcos Flavio de Campos jose Adilson de castro department of Mechanical Engineering Federal Fluminense University

Several different models for coercivity are discussed. There are two main situations: i) nanocrystalline magnets, with grain size bellow the single domain particle size, and ii) magnets with grain size above single domain particle size. The described theories and models are general, and can be applied in either NdFeB magnets, SmFeCoCuZr or strontium ferrite magnets. The spring effect observed in isotropic nanocrystalline magnets can be explained with the Stoner-Wohlfarth model. Modifications of the StonerWohlfarth model are necessary to take into account the effect of interaction between grains. When the grain size is above the single domain size, energy considerations show that nucleation should occur at the surface of grains. Nucleation is interpreted as a two-step process, where domain wall displacement occurs for grain size above single domain size, after a nucleus is first formed. The effect of grain size on the coercive field is discussed.

关键词： Coercivity Nucleation Grain size Spring effect Nd-Fe-B Permanent magnet

COMBINING SINGULAR SPECTRUM ANALYSIS AND PAR(p) STRUCTURES TO MOdeL WIND SPEED TIME SERIES

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Journal of Systems Science & Complexity 2014年第1期27卷 29-46页

作者： MENEZES Moises Lima de SOUZA Reinaldo castro PESSANHA Jos francisco Moreira department of Statistics Fluminense Federal University ( UFI~ Brazil. Email: moisesAima@msn.com.SOUZA Reinaldo Castro Electrical Engineering department: Pontifical Catholic University of Rio de Janeiro (PUC-Rio) Brazil. Institute of Mathematics and Statistics State University of Rio de Janeiro (UERJ) Brazil.

Singular spectrum analysis （SSA） is a technique that decomposes a time series into a set of components, such as, trend, harmonics, and residuals. Leaving out the residual components and adding up the others, the time series can be smoothed. This procedure has been used to model Brazilian electricity consumption and flow series. The PAR（p）, periodic autoregressive models, has been broadly used in modelling energy series in Brazil. This paper presents an approach of this decomposition method, by fitting the PAR（p）, considering its multivariate version known as multivariate SSA （MSSA）. The method was applied to a vector of two wind speed series recorded at two locations in the Brazilian Northeast region. The obtained results, when compared to the univariate decomposition of each series, were far superior, showing that the spatial correlation between the two series were considered by MSSA decomposition stage.

关键词： MSSA periodic autoregressive model SSA wind speed series.

Challenges and improvement strategies in the hospitalization of chronic multimorbid patients

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World Journal of Clinical Cases 2025年第3期13卷 35-41页

作者： Andres Fontalba-Navas francisco Pozo Muñoz Rogelio Garcia Cisneros Maria jose Garcia Larrosa Maria del Mar Callejon Gil Ignacio Garcia delgado Maria Belen Jimenez Martinez Antequera Hospital Northern Málaga Integrated Healthcare AreaAntequera 29200AndalusiaSpain department of Public Health and Psychiatry University of MálagaMálaga 29010Spain Antequera Hospital Northern Málaga Antequera Integrated Healthcare AreaAntequera 29200MálagaSpain

BACKGROUND Addressing the growing challenge of hospitalizing chronic multimorbid patients,this study examines the strain these conditions impose on healthcare systems at a local level,focusing on a pilot *** diseases and complex patients require comprehensive management strategies to reduce healthcare burdens and improve patient *** proven effective,this pilot model has the potential to be replicated in other healthcare settings to enhance the management of chronic multimorbid *** To evaluate the effectiveness of the high complexity unit(HCU)in managing chronic multimorbid patients through a multidisciplinary care model and to compare it with standard hospital *** The study employed a descriptive longitudinal approach,analyzing data from the Basic Minimum Data Set(BMDS)to compare hospitalization variables among the HCU,the Internal Medicine Service,and other services at Antequera Hospital throughout *** HCU,designed for patients with complex chronic conditions,integrates a patient-centered model emphasizing multidisciplinary care and continuity *** The study employed a descriptive longitudinal approach,analyzing data from the BMDS to compare hospitalization variables among the HCU,the Internal Medicine Service,and other services at Antequera Hospital throughout *** HCU,designed for patients with complex chronic conditions,integrates a patient-centered model emphasizing multidisciplinary care and continuity *** This study demonstrates the effectiveness of the HCU in managing patients with complex chronic diseases through a multidisciplinary *** coordinated care provided by the HCU results in improved patient outcomes,reduced unnecessary hospitalizations,and better management of patient *** superiority of the HCU compared to standard care is evident in key outcomes such as fewer readmissions and higher patient satisfaction,reinforcing its value as a model of ca

关键词： High complexity unit Chronic multimorbidity Patient-centered care Integrated care Healthcare management

Acromyrmex ameliae sp. n. （Hymenoptera： Formicidae）： A new social parasite of leaf-cutting ants in Brazil

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Insect Science 2007年第3期14卷 251-257页

作者： DANIVAL jose de SOUZA ILKA MARIA FERNANdeS SOARES TEREZINHA MARIA castro deLLA LUCIA Institut de Recherche sur la Biologie de 1'Insecte Université Francois Rabelais Tours France departamento de Biologia Animal Laboratório de Ecologia de Comunidades Departamento de Biologia Geral Universidade Federal de Vicosa MG 36570-000 Brazil

The fungus-growing ants （Tribe Attini） are a New World group of〉 200 species, all obligate symbionts with a fungus they use for food. Four attine taxa are known to be social parasites of other attines. Acromyrmex （ Pseudoatta） argentina argentina and Acromyrmex （Pseudoatta） argentina platensis （parasites of Acromyrmex lundi）, and Acromyrmex sp. （a parasite of Acromyrmex rugosus） produce no worker caste. In contrast, the recently discovered Acromyrmex insinuator （a parasite of Acromyrmex echinatior） does produce workers. Here, we describe a new species, Acromyrmex ameliae, a social parasite of Acromyrmex subterraneus subterraneus and Acromyrmex subterraneus brunneus in Minas Gerais, Brasil. Like A. insinuator, it produces workers and appears to be closely related to its hosts. Similar social parasites may be fairly common in the fungus-growing ants, but overlooked due to the close resemblance between parasite and host workers.

关键词： Acromyrmex leaf-cutting ants social evolution social parasitism

Analysing vaccine efficacy evaluated in phase 3 clinical trials carried out during outbreaks

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Infectious Disease Modelling 2024年第4期9卷 1027-1044页

作者： francisco Antonio Bezerra Coutinho Marcos Amaku Fernanda castro Boulos jose Alfredo de Sousa Moreira Joao Italo DiasFranca Julio Antonio do Amaral Eliana Nogueira castro de Barros Claudio jose Struchiner Esper Jorge Kallas Eduardo Massad School of Medicine University of Sao PauloBrazil Instituto Butantan Sao PauloBrazil School of Applied Mathematics Fundacao Getulio VargasRio de JaneiroBrazil

In this paper we examine several definitions of vaccine efficacy(VE)that we found in the literature,for diseases that express themselves in outbreaks,that is,when the force of infection grows in time,reaches a maximum and then *** fact that the disease occurs in outbreaks results in several problems that we *** propose a mathematical model that allows the calculation of VE for several *** trials usually needs a large number of volunteers that must be ***,all volunteers should be enrolled in approximately the same time,but this is generally impossible for logistic reasons and they are enrolled in a fashion that can be replaced by a continuous density function(for example,a Gaussian function).The outbreak can also be replaced by a continuous density function,and the use of these density functions simplifies the ***,for example Gaussian functions,one of the problems one can immediately notice is that the peak of the two curves do not occur at the same *** model allows us to conclude:First,the calculated vaccine efficacy decreases when the force of infection increases;Second,the calculated vaccine efficacy decreases when the gap between the peak in the force of infection and the peak in the enrollment rate increases;Third,different trial protocols can be simulated with this model;different vaccine efficacy definitions can be calculated and in our simulations,all result are approximately the *** final,and perhaps most important conclusion of our model,is that vaccine efficacy calculated during outbreaks must be carefully examined and the best way we can suggest to overcome this problem is to stratify the enrolled volunteer's in a cohort-by-cohort basis and do the survival analysis for each cohort,or apply the Cox proportional hazards model for each cohort.

关键词： Vaccine efficacy Clinical trials Mathematical models Simulations Covid-19

Investigation of Galactic open cluster remnants： the case of NGC 7193

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Research in Astronomy and Astrophysics 2017年第1期17卷 31-54页

作者： Mateus de Souza Angelo Joao francisco Coelho dos Santos Jr Wagner jose Barbosa Corradi francisco Ferreira de Souza Maia Andres Eduardo Piatti departamento de Fisica ICEx Universidade Federal de Minas Gerais Av. Antonio Carlos 6627 31270-901 Belo Horizonte MG Brazil Observatorio Astronomico Universidad Nacional de Cordoba Laprida 854 5000 Cordoba Argentina Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. Rivadavia 1917 C1033AAJ Buenos AiresArgentina

Galactic open clusters （OCs） that survive the early gas-expulsion phase are gradually de- stroyed over time by the action of disruptive dynamical processes. Their final evolutionary stages are characterized by a poorly populated concentration of stars called an open cluster remnant （OCR）. This study is devoted to assessing the real physical nature of the OCR candidate NGC 7193. GMOS/Gemini spectroscopy of 53 stars in the inner target region were obtained to derive radial velocities and at- mospheric parameters. We also employed photometric and proper motion data. The analysis method consists of the following steps：（i） analysis of the statistical resemblance between the cluster and a set of field samples with respect to the sequences defined in color-magnitude diagrams （CMDs）; （ii） a 5-dimensional iterative exclusion routine was employed to identify outliers from kinematical and posi- tional data; （iii） isochrone fitting to thes× （J - Ks） CMD of the remaining stars and the dispersion of spectral types along empirical sequences in the （J - H） × （H - Ks） diagram were checked. A group of stars was identified for which the mean heliocentric distance is compatible with that obtained via isochrone fitting and whose metallicities are compatible with each other. Fifteen of the member stars observed spectroscopically were identified together with another 19 probable members. Our results indi- cate that NGC 7193 is a genuine OCR, of a once very populous OC, for which the following parameters were derived： d = 501±46 pc, t = 2.5±1.2 Gyr, （[Fe/H]） = -0.17±0.23 and E（B-V） = 0.05±0.05. Its luminosity and mass functions show depletion of low mass stars, confirming the OCR is in a dynam- ically evolved state.

关键词： open cluster remnants - Galactic open clusters

Different culture conditions applied to in vitro shoot multiplication of two Eucalyptus benthamii explant sources

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Journal of Forestry Research 2020年第3期31卷 857-869页

作者： Natalia Pimentel Esposito-Polesi Leandro Silva de Oliveira francisco jose Benedini Baccarin Cristina Vieira de Almeida Marcilio de Almeida Biological Science department "Luiz de Queiroz"Superior College of AgricultureUniversity of Sao Paulo(ESALQ/USP)Padua Dias Avenue11P.O.Box 9PiracicabaSP 13418-900Brazil Institute of Agriculture Sciences Federal University of Minas Gerais(UFMG)Universitaria Avenue1000Montes ClarosMG 39404-547Brazil State University of Goias(UEG) Rua S7Qd.1S SulPalmeiras de GoiasGO 76190-000Brazil In vitro Palm Consultoria Estudo e Desenvolvimento Biologico LtdaRua Itajobi421PiracicabaSP 13432-000Brazil

Eucalyptus adult material requires more successive subcultures in the in vitro multiplication phase for increased vigor and cellular activity. This study evaluated the endophytic manifestation and shoot multiplication of one 13-year-old Eucalyptus benthamii clone under different culture conditions and used canopy branches(CB) and trunk base material as explant sources. The culture media were wood plant medium(WPM), Murashige and Skoog medium(MS) and JADS(Correia and co-authors medium).Based on the results of the initial multiplication experiment, further tests examined sucrose concentrations and p H. Morphophysiology, dry mass production, endophyticmanifestation and histochemical were determined. Explant sources responded differently to MS and JADS media, but the WPM medium promoted homogeneous *** responses were similar for both explant sources when sucrose concentrations varied. Shoots died in the absence of sucrose, showed high oxidation at 60 g L-1 and optimal development at 30 g L-1. Endophytes were more evident for shoots from the CB origin. Explant sources responded distinctively to treatment due to physiological and intrinsic genetic factors. Therefore, explant sources, different culture media, sucrose concentration and p H may determine micropropagation success and influence the presence and/or intensity of endophytic manifestation.

关键词： Plant tissue culture Explant sources Culture media Sucrose pH

Bioleaching of zinc from gold ores using Acidithiobacillus ferrooxidans

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 368-374页

作者： Pakawadee Kaewkannetra francisco jose Garcia-Garcia Tze Yen Chiu department of Biotechnology Faculty of TechnologyKhon Kaen University Corrosion and Protection Centre School of MaterialsThe University of Manchester Centre of Water Science Cranfield University

The present work investigated microbial leaching of zinc from ore using Acidithiobacillus ferrooxidans （ATCC 14859）. The ore samples, consisted of 13wt% zinc, were obtained from a gold mine in north-eastern Thailand. A shake flask study was performed on the ore samples using a rotary shaker under the following fixed conditions （250 r·min^-1, 30℃ for 16 d）. The influence of various conditions, namely medium type （with and without iron）, particle ore size （〈20, 20-40, 40-60, 60-100, and 〉100 mesh）, ore density （20 kg·m^-3, 50 kg·m^-3, and 100 kg·m^-3）, and pH of the medium （2, 2.5, 2.8, and 3）, were investigated. The microbial leaching was assessed by determining the concentration of zinc in the medium and compared with the initial sample concentration. The results show that Acidithiobacillus ferrooxidans can successfully leach zinc by as much as 6 times compared with the control experiment （without Acidithiobacillus ferrooxidans ferrooxidans）. The maximum efficiency （92.3%） for microbial leaching is obtained in iron-containing medium, 20-40 mesh ore sizes, 20 kg·m^-3 ore density at pH 2.8, and the zinc content is found in the medium at about 120 mg·m^-1.

关键词： bioleaching Acidithiobacillusferrooxidans gold ores gold mine

determining indoor air quality and identifying the origin of odour episodes in indoor environments

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Journal of Environmental Sciences 2009年第3期21卷 333-339页

作者： Eva Gallego Xavier Roca jose francisco Perales Xavier Guardino Environmental Centre Laboratory Polytechnic University of Catalonia (LCMA-UPC) Avda Diagonal 647 E 08028 Barcelona Spain National Centre of Work Conditions (INSHT) Dulcet 2-10 E 08034 Barcelona Spain

A methodology for identifying volatile organic compounds （VOCs） and determining air quality of indoor air has been developed. The air samples are collected using pump samplers by the inhabitants when they perceive odorous and/or discomfort episodes. Glass multi-sorbent tubes are connected to the pump samplers for the retention of VOC. The analysis is performed by automatic thermal desorption （ATD） coupled with gas chromatography-mass spectrometry （GC/MS）. This methodology can be applied in cases of sick building syndrome （SBS） evaluation, in which building occupants experience a series of varied symptoms that appear to be linked to time spent in the building. Chemical pollutants concentrations （e.g., VOC） have been described to contribute to SBS. To exemplify the methodology, a qualitative determination and an evaluation of existing VOC were performed in a dwelling where the occupants experienced the SBS symptoms. Higher total VOC （TVOC） levels were detected during episodes in indoor air （1.33 ±1.53 mg/m^3） compared to outdoor air （0.71± 0.46 mg/m^3）. The concentrations of individual VOCs, such as ethanol, acetone, isopropanol, 1-butanol, acetic acid, acetonitrile and 1-methoxy-2-propanol, were also higher than the expected for a standard dwelling. The external source of VOC was found to be an undeclared activity of storage and manipulation of solvents located at the bottom of a contiguous building.

关键词： indoor air thermal desorption TVOC VOC sick building syndrome