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Data–driven decision–making for lost circulation treatments: A machine learning approach

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能源与人工智能(英文) 2020年第2期2卷 125-135页

作者： Husam H.Alkinani Abo Taleb T.Al-Hameedi shari dunn-norman Missouri University of Science and Technology 1201 N State StRollaMO 65409USA

Lost circulation is an expensive and critical problem in the drilling *** of dollars are spent every year to mitigate or stop this *** this work,data from over 3000 wells were collected from multiple *** data went through a processing step where all outliers were removed and decision rules were set *** machine learning methods(support vector machine,decision trees,logistic regression,artificial neural networks,and ensemble trees)were used to create a model that can predict the best lost circulation treatment based on the type of loss and the reason of loss.5-fold cross-validation was conducted to ensure no overfitting in the created *** using all the aforementioned machine learning methods to train models to choose the best lost circulation treatment,overall,the results showed that support vector machine had the highest accuracy among the other ***,it was selected to train the *** created model went through quality control/quality assurance(QC/QA)to limit the results of incorrect *** treatments were suggested to treat partial loss,four to treat severe loss,and seven for complete loss,based on the reason of *** addition,a formalized methodology to respond to lost circulation was provided to help the drilling personnel handling lost circulation in the field.

关键词： Machine learning Lost circulation Data-driven Classification

肠上皮细胞Axin1缺失可调节肠道微生态预防结肠炎

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Engineering 2024年第4期35卷 241-256页

作者： shari Garrett Yongguo Zhang Yinglin Xia Jun Sun Division of Gastroenterology and Hepatology Department of MedicineUniversity of Illinois ChicagoChicagoIL 60612USA Department of Microbiology and Immunology College of MedicineUniversity of Illinois ChicagoChicagoIL 60612USA Cancer Center University of Illinois ChicagoChicagoIL 60612USA Jesse Brown VA Medical Center ChicagoIL 60612USA

Intestinal homeostasis is maintained by specialized host cells and the gut ***/β-catenin signaling is essential for gastrointestinal development and homeostasis,and its dysregulation has been implicated in inflammation and colorectal ***1 negatively regulates activated Wnt/β-catenin signaling,but little is known regarding its role in regulating host–microbial interactions in health and ***,we aim to demonstrate that intestinal Axin1 determines gut homeostasis and host response to ***1 expression was analyzed in human inflammatory bowel disease *** explore the effects and mechanism of intestinal Axin1 in regulating intestinal homeostasis and colitis,we generated new mouse models with Axin1 conditional knockout in intestinal epithelial cell(IEC;Axin1^(ΔIEC))and Paneth cell(PC;Axin1^(ΔPC))to compare with control(Axin1^(LoxP);LoxP:locus of X-over,P1)*** found increased Axin1 expression in the colonic epithelium of human inflammatory bowel disease(IBD).Axin1^(ΔIEC) mice exhibited altered goblet cell spatial distribution,PC morphology,reduced lysozyme expression,and enriched Akkermansia muciniphila(***).The absence of intestinal epithelial and PC Axin1 decreased susceptibility to dextran sulfate sodium(DSS)-induced colitis in ***1^(ΔIEC) and Axin1^(ΔPC)mice became more susceptible to DSS-colitis after cohousing with control *** with *** reduced DSS-colitis *** treatment did not change the IEC proliferation in the Axin1Loxp ***,the intestinal proliferative cells in Axin1^(ΔIEC)mice with antibiotic treatment were reduced compared with those in Axin1^(ΔIEC) mice without *** data suggest non-colitogenic effects driven by the gut *** conclusion,we found that the loss of intestinal Axin1 protects against colitis,likely driven by epithelial Axin1 and Axin1-associated *** study demonstrates a novel role of Axin1 in mediating intes

关键词： Axin1 Bacteria Microbiome inflammation Inflammatory bowel disease Immunity Microbiome Paneth cells Akkermansia muciniphila Wnt

Transforming nanoscale VO_(2)(B) into a scalable sodium-ion electrode

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Nano Research 2024年第10期17卷 8809-8818页

作者： Yunkai Luo Swetha Chandrasekaran Bintao Hu Randy Chen Marcus Worsley Bruce dunn Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 90095USA Lawrence Livermore National Laboratory CA 94550USA

The intermittent nature of renewable energies requires highly reliable grid-level energy storage approaches.A critical consideration in developing this technology is the areal capacity which determines battery performance and influences the cost of battery *** related importance is finding new ways of developing scalable *** recent years,threedimensional(3D)printing of conductive scaffolds has emerged as an alternative to overcome the scalability limitations of commercial tape cast *** research carried out in the current study demonstrates a successful scalability pathway for nanoscale VO_(2)(B),a desirable cathode for sodium-ion batteries which has a nano-flower morphology with a crystallite size<20 *** electrodepositing VO_(2)(B)onto a graphene aerogel scaffold,we were able to achieve mass loading of over 100 mg·cm^(-2) and still possess an areal capacity of 10 mAh·cm^(-2) at a current density of 5 mA·cm^(-2).Moreover,after 1000 cycles,these electrodes retained 75% to 80% of their initial *** at high loading levels,the electrodeposited VO_(2)(B)exhibits pseudocapacitive material signatures such as a box-like voltammetry response,linear galvanostatic response,and no phase change upon *** scalability of the VO_(2)(B)electrode is demonstrated in a series of experiments which show the areal capacity to scale upon increase in both mass loading and electrode thickness,with only small changes in specific *** study establishes that nanoscale materials can be scaled up to achieve thick electrodes without compromising their electrochemical properties.

关键词： nano VO_(2)(B) sodium-ion battery scalable electrodes three-dimensional(3D)printed scaffold additive manufacturing

VR-based digital twin for remote monitoring of mining equipment:Architecture and a case study

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 100-112页

作者： Jovana PLAVŠIĆ Ilija MIŠKOVIĆnorman BKeevil norman B.Keevil Institute of Mining Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada

Background Traditional methods for monitoring mining equipment rely primarily on visual inspections,which are time-consuming,inefficient,and *** article introduces a novel approach to monitoring mission-critical systems and services in the mining industry by integrating virtual reality(VR)and digital twin(DT)***-based DTs enable remote equipment monitoring,advanced analysis of machine health,enhanced visualization,and improved decision *** This article presents an architecture for VR-based DT development,including the developmental stages,activities,and stakeholders involved.A case study on the condition monitoring of a conveyor belt using real-time synthetic vibration sensor data was conducted using the proposed *** study demonstrated the application of the methodology in remote monitoring and identified the need for further development for implementation in active mining *** article also discusses interdisciplinarity,choice of tools,computational resources,time and cost,human involvement,user acceptance,frequency of inspection,multiuser environment,potential risks,and applications beyond the mining *** The findings of this study provide a foundation for future research in the domain of VR-based DTs for remote equipment monitoring and a novel application area for VR in mining.

关键词： Virtual reality Digital twin Condition monitoring Mining equipment

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

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Railway Engineering Science 2024年第3期32卷 361-383页

作者： Olga Nabochenko Mykola Sysyn norman Krumnow Szabolcs Fischer Institute of Railway Systems and Public Transport Technical University of DresdenDresdenGermany Rhomberg Sersa Deutschland GmbH BerlinGermany Central Campus Győr Széchenyi István UniversityGyorHungary

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance ***,the mechanism of the irregularities initiation and development is *** motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted *** long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional ***,wide sleepers had higher twist and cross-section level *** present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper *** DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional ***,the cross-level differential settlements are almost the same for both *** particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper *** flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level *** mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper *** further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the *** DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

关键词： Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation

Recent advances in the magnetic reconnection, dipolarization, and auroral processes at giant planets from the perspective of comparative planetology

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Earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao RuiLong Guo Yong Wei Bertrand Bonfond Denis Grodent BinZheng Zhang William R.dunn ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde Liège Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University Department of Earth Sciences the University of Hong Kong Department of Physics and Astronomy University College London School of Earth and Space Sciences Peking University

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics, including particle energization, mass circulation, and auroral processes, among others. Recent studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at Earth. The reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially Jupiter. Dayside magnetodisc reconnection was directly identified by using Cassini measurements(Guo RL et al., 2018b) and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al., 2015b; Yao ZH et al., 2017a; Guo RL et al., 2019). Moreover, magnetic dipolarization could also exist at Saturn's dayside(Yao ZH et al., 2018), which is fundamentally different from the terrestrial situation. These new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary aurorae. Here, we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.D.Küntz D.Koutroumpa W.R.dunn A.Foster F.S.Porter D.G.Sibeck B.Walsh The Henry A.Rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Diet variability of snappers(Teleostei:Lutjanidae)in a bay-to-reef ecosystem of the Mexican Caribbean

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Water Biology and Security 2024年第1期3卷 53-59页

作者： Leon Felipe Martínez-Juarez Juan J.Schmitter-Soto Nancy Cabanillas-Teran norman Mercado-Silva El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Centro de Investigacion en Biodiversidad y Conservacion Universidad Autonoma del Estado de Morelos62209CuernavacaMorelosMexico

Fishes use environmental resources *** ontogenic movements among coastal habitats lead to diverse *** investigated the diets of seven snapper species(Lutjanus apodus,***,***,***,***,***,and Ocyurus chrysurus)in three interconnected coastal environments in the western Caribbean:Río Huach channel,Chetumal/Corozal bay,and the adjacent Xcalak reef *** three encompass all habitats used by the seven species in the study *** diets were mostly composed of fish and crustaceans,but dominance of either group varied among the studied habitats;for example,fish were the main prey for *** from the reef lagoon zone,but second in the *** are piscivorous-invertivorous mesopredators;the species that relied the most on fishes were *** and ***,whereas *** preferred *** content results revealed a high degree of dietary overlap among *** findings suggested a tradeoff in relative weight between fish and crustaceans as the main food source of snappers at these connected areas,supporting the hypothesis of niche *** results can be used as a baseline to further our understanding of the ecology and differences in resource use by snapper species in an area undergoing important anthropogenic changes.

关键词： Resource partitioning Chetumal/Corozal bay Quintana Roo Trophic ecology

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互惠合作系统的非对称性和不确定性

Journal of Plant Ecology 2024年第1期17卷 172-186页

作者： Rui-Wu Wang An-Na Shi Xiao-Wei Zhang Min Liu K.Charlotte Jandér Derek W.dunn School of Ecology and Environment Northwestern Polytechnical UniversityXi’an 710072China Faculty of Education University of MalayaKuala Lumpur 50400Malaysia College of Life Sciences Shaanxi Normal UniversityXi’an 710119China Department of Organismic and Evolutionary Biology Harvard UniversityMA 02138USA College of Life Sciences Northwest UniversityXi’an 710069China

过去的几十年里,尽管对互惠合作系统稳定性的理解取得了较大的进展,但在解释互惠关系如何保持稳定方面仍然存在两个基本问题。(i)如何解决互惠合作双方之间的资源冲突?(ii)当存在不怎么合作和/或完全不合作的共生体时,为什么合作的共生... 详细信息

过去的几十年里,尽管对互惠合作系统稳定性的理解取得了较大的进展,但在解释互惠关系如何保持稳定方面仍然存在两个基本问题。(i)如何解决互惠合作双方之间的资源冲突?(ii)当存在不怎么合作和/或完全不合作的共生体时,为什么合作的共生体没有被不合作的个体竞争排斥掉?过去许多关于互惠稳定性的解释都假设互惠合作双方的相互作用是对称的。然而,在大多数共生关系中,宿主和共生体之间的相互作用在不同水平上表现出不同程度的非对称性。本文我们回顾了互惠合作系统中的三种主要的非对称相互作用:(i)收益非对称,也就是合作双方的实力非对称性;(ii)潜在进化速率非对称性;(iii)宿主和共生体之间的信息非对称性。我们认为,互惠合作系统非对称性有助于解释合作和冲突行为的不确定性(合作与竞争的内生不确定性),以及为什么宿主和共生体都呈现出多样化的表型特征,而合作仍可占主导地位。

关键词：互利共生不对称相互作用宿主惩罚进化速率欺骗