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Study on brittleness templates for shale gas reservoirs——A case study of Longmaxi shale in Sichuan Basin,southern China

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Petroleum Science 2021年第5期18卷 1370-1389页

作者： Qamar Yasin Ghulam Mohyuddin Sohail Ke-Yu Liu Qi-Zhen Du cyril dboateng The Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China Qingdao National Laboratory for Marine Science and Technology Laboratory for Marine Mineral ResourcesQingdao266237China Department of Civil Geological and Environmental EngineeringUniversity of SaskatchewanSaskatoonS7N 5C5Canada Department of Geological Engineering University of Engineering and TechnologyLahorePakistan

Differentiating brittle zones from ductile zones in low permeability shale formations is imperative for efficient hydraulic fracturing *** brittleness index(BI) is used to describe the rock resistance to hydraulic fracture initiation and propagation and measures the ease at which complex fracture networks can be *** this study,we constructed brittleness templates through the correlation of fundamental rock properties and geomechanical *** then employed the templates to distinguish the brittle,ductile,and brittle-ductile transition zones in the Longmaxi shale gas reservoir,Sichuan Basin of southern *** approach works in two ***,we suggest a new expression for the mineralogical BI by their respective weights based on the analysis of correlation coefficients between mechanical testing and XRD ***,we correlate TOC,porosity,pore fluid,natural fractures,and improved BI model with multiple elastic properties to define the brittle,ductile,and transitional zones in the Longmaxi shale gas reservoir of *** with the traditional mineralogy-based BI definition,the improved BI model differentiates the brittle and ductile zones and provides a better sense of the most suitable fracturing *** results show that the brittleness templates,which combine fundamental rock properties,improved BI model,and geomechanical characterization led to identifying favorable zones for hydraulic fracturing and enhanced shale *** proposed brittleness templates’ effectiveness was verified using data from horizontal wells,offset wells,shale gas wells from different origins,laboratory core testing,and seismic inversion of BI across the studied wells.

关键词： Brittleness index Geomechanical properties Petrophysical parameters Longmaxi shale

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Stable diffusion gradients in microfluidic conduits bounded by fluid walls

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Microsystems & Nanoengineering 2024年第3期10卷 357-367页

作者： Federico Nebuloni cyril Deroy Peter R.Cook Edmond J.Walsh Department of Engineering Science Osney Thermo-Fluids InstituteUniversity of OxfordOxford OX20ESUK Sir William Dunn School of Pathology University of OxfordOxford OX13REUK

Assays mimicking in vitro the concentration gradients triggering biological responses like those involved in fighting infections and blood clotting are essential for biomedical *** assays prove especially attractive as they allow precise control of gradient shape allied to a reduction in *** microfluidic devices are fabricated using solid plastics that prevent direct access to responding ***-walled microfluidics allows the manufacture of circuits on standard Petri dishes in seconds,coupled to simple operating methods;cell-culture medium sitting in a standard dish is confined to circuits by fluid walls made of an immiscible *** develop and experimentally validate an analytical model of diffusion between two or more aqueous streams flowing at different rates into a fluid-walled conduit with the cross-section of a circular *** solid walls,fluid walls morph during flows as pressures fall,with wall shape changing down the *** model is validated experimentally for Fourier numbers<0.1 using fluorescein diffusing between laminar *** enables a priori prediction of concentration gradients throughout a conduit,so allowing rapid circuit design as well as providing bioscientists with an accurate way of predicting local concentrations of bioactive molecules around responsive and nonresponsive cells.

关键词： walls diffusion attractive

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Bulk geochemistry,Rb-Sr,Sm-Nd,and stable O-H isotope systematics of the Metzimevin high-grade iron ore deposit,Mbalam iron ore district,southern Cameroon

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Acta Geochimica 2024年第4期43卷 677-706页

作者： Samndong cyril Tufoin Cheo Emmanuel Suh Tabod Charles Tabod George Lemewihbwen Ngiamte Department of Geology Mining and Environmental ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Economic Geology Unit Department of GeologyUniversity of BueaP.O.63BueaSouth West RegionCameroon Department of Physics Faculty of ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Department of Geology Pan-African University Life and Earth Sciences Institute(PAULESI)University of IbadanIbadanNigeria

Bulk geochemistry,Sr,Nd,and O-H isotope systematics are reported for the first time on banded iron formation(BIF)-hosted high-grade iron ore at the northwestern segment of Congo Craton(CC).Located in Mbalam iron ore district,Southern Cameroon,Metzimevin iron ore deposit is a hematite-magnetite BIF system,dominated by SiO_(2)+Fe_(2)O_(3)(97.1 to 99.84 wt%),with low concentrations of clastic elements e.g.,Al_(2)O_(3),TiO_(2),and HFSE,depicting a nearly pure chemical *** REE+Y signature of the iron deposit displays strong positive Eu anomaly,strong negative Ce anomaly,and chondritic to superchondritic Y/Ho ratios,suggestive of formation by mixed seawater-high temperature hydrothermal fluids in oxidising ***^(87)Sr/^(86)Sr ratios of the BIF are higher than the maximum^(87)Sr/^(86)Sr evolution curves for all Archean reservoirs(bulk silicate earth,Archean crust and Archean seawater),indicating involvement of continentally-derived components during BIF formation and ***Ɛ_(Nd)(t)(+2.26 to+3.77)and Nd model age indicate that chemical constituents for the BIF were derived from undifferentiated crustal source,between 3.002 and 2.88 *** variable and diverse O and H isotope data(−1.9‰to 17.3‰and−57‰to 136‰respectively)indicate that the Metzimevin iron ore formed initially from magmatic plumes and later enriched by magmatic-metamorphic-modified meteoric *** balance calculations indicate mineralisation by combined leaching and precipitation,with an average iron enrichment factor of>2.67 and SiO_(2)depletion factor of>*** is associated with an overall volume reduction of 28.27%,reflecting net leaching and volume collapse of the BIF protholith.

关键词： Bulk geochemistry Rb-Sr Sm-Nd Mitzimevin High-grade iron ore

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A survey on automatic dashboard recommendation systems

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Visual Informatics 2024年第1期8卷 67-79页

作者： Praveen Soni cyril de Runz Fatma Bouali Gilles Venturini LIFAT University of Tours64 avenue Jean PortalisTours37200France IUT C University of Lille53 Rue de l’AlmaRoubaix59100France

This paper presents a survey on automatic or semi-automatic recommendation systems that help users create *** starts by showing the important role that dashboards play in data science,and gives an informal definition of dashboards,i.e.,a set of visualizations possibly with linkage,a screen layout and user *** are mainly interested in systems that use a fully or partially automatic mechanism to recommend dashboards to *** automation includes the suggestion of data and visualizations,the optimization of the layout and the use of user *** position our work with respect to existing *** from a set of over 1000 papers,we have selected and analyzed 19 papers/systems along several *** main dimensions were the set of considered visualizations,the suggestion method,the utility/objective functions,the layout,and the user *** conclude by highlighting the main achievements in this domain and by proposing perspectives.

关键词： Automatic visualization Dashboard recommendation Multiple view interfaces

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Structural effects of reedbed grazing and its cessation on reed-nesting songbird densities

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Avian Research 2024年第2期15卷 238-248页

作者： Thomas Pagnon Clemence Pechinot Lea Sgro Jeremie Demay Remi Jullian Regis Gallais Brigitte Poulin cyril Marmoex Theria Ecologie 6 avenue des martyrs05400VeynesFrance UMR 6249 Chrono-Environnement CNRSUniversite de Franche-Comte16 route de Gray25000BesanconFrance Conservatoire d’Espaces Naturels d’Occitanie 26 alle de Mycenes34000MontpellierFrance Office Français de la Biodiversite 12 cours Lumiere94300VincennesFrance Tour du Valat Research Institute for the Conservation of Mediterranean Wetlands Le Sambuc13200ArlesFrance

Reedbeds are crucial breeding habitats for vulnerable songbird *** of their protection status,these habitats may be threatened by organic matter accumulation,progressively leading to structural homoge-nization and habitat succession towards *** prevent excessive litter build-up with various in-terventions opening-up the reedbeds,such as grazing,which may be detrimental or suitable for some reed bird *** assessed the effects of extensive grazing by horses and its cessation in the medium and long terms on reedbed structure,and the consequences on reed-nesting songbird densities in Estagnol Nature Reserve,a pro-tected wetland near the French Mediterranean *** compared reedbed structural features between grazed,newly ungrazed and old-ungrazed *** nine years,we censused four songbird species in spring and collected water level data in the same survey *** reduced reedbed extent,rejuvenated the vegetation with more short green stems on a thinner litter,and produced higher structural heterogeneity and discontinuity compared to long-lasting non *** ungrazed plot showed intermediate *** surveyed songbird total densities were similar among plots while species numbers and densities *** reedbed was more attractive to Moustached Warblers(Acrocephalus melanopogon)and Great Reed Warblers(Acrocephalus arundi-naceus),likely due to the large edges and the high vegetation structural ***,Moustached Warblers were more negatively affected by higher water level in grazed reedbed,presumably because flooding prevents litter *** newly ungrazed reedbed was not preferred by any *** warbler species were found under low density in the old-ungrazed reedbed,where Reed Buntings(Emberiza schoeniclus)were exclu-sively *** availability related to thick litter layer may explain this *** Reed Warblers(Acrocephalus scirpaceus)were found everywhere in similar

关键词： Bird conservation Edge complexity Fragmentation Habitat management Horse grazing Phragmites australis Reed passerine

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Analysis of the Digital Skill Gap of Agricultural Extension Personnel in South-East, Nigeria

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Agricultural Sciences 2024年第9期15卷 1057-1070页

作者： Ogbonnaya Okoro Aja Chigozie cyril Asiabaka Anthony Okorie Ani Edna Chioma Matthews-Njoku Department of Agricultural Extension Federal University of Technology Owerri Nigeria

The study analysed the digital skill gap of agricultural extension personnel on the use of digital technologies for extension services delivery in South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in South-East Nigeria and identify the digital skill gaps among agricultural extension personnel in the area of study. Purposive sampling technique was used to select 364 Agricultural Extension personnel for the study. Data were collected through the use of structured questionnaire and were analysed using simple descriptive statistical tools such as percentages, mean score, and standard deviation. Findings indicated that most of the personnel were male (57.8%), within the age bracket of 38 - 47 years (62.9%), had ***./HND as their highest educational qualification (74.7%), married (86.3%), and had a household size of 6 - 10 Persons (57.7%). It was further revealed that the majority (70.1%) were members of professional organization, earned a monthly income of N50,001.00 - N100,000.00 (65.7%), had a work experience of 11 - 15 years (51.1%), and owned a smartphone/ iPad/laptop (91.5%). Findings further indicated that they had moderate skill gap in Basic Computer skills (Mean = 4.32), and digital communication and collaboration skills (Mean = 4.26). Findings also showed that they had a high skill gap in digital technical skills (Mean = 2.46), digital data analysis skills (Mean = 2.09), digital content creation skills (Mean = 2.43), digital ethical skills (Mean = 2.79), multimedia production skills (Mean = 2.81), and video library management skills (Mean = 2.39). The study concluded that though there exists a high digital skill gap among agricultural extension personnel in South-East, Nigeria, their socioeconomic characteristics are capable of supporting the implementation of digital extension services in the area. The study recommended that the management of Agricultural Development Programs in

关键词： Agricultural Extension Personnel Socioeconomic Characteristics Digital Skill Gap South-East Nigeria

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Comparative Study of the Socioeconomic Characteristics and Digital Literacy Level of Agricultural Extension Personnel in Imo and Ebonyi States, South-East, Nigeria

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Agricultural Sciences 2024年第2期15卷 230-245页

作者： Ogbonnaya Okoro Aja cyril Chigozie Asiabaka Anthony Okorie Ani Edna Chioma Matthews-Njoku Department of Agricultural Extension Federal University of Technology Owerri Nigeria

The study comparatively analysed the socioeconomic characteristics and digital literacy level of Agricultural Extension personnel (AEP) in Ebonyi and Imo States, South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in Ebonyi and Imo States, and to ascertain the digital literacy level of AEP in the studied states. Purposive sampling technique was used to select 312 Agricultural Extension personnel (132 from Ebonyi State Agricultural Development Program and 180 from Imo State Agricultural Development Program) for the study. Data were collected through the use of validated and structured questionnaire, and administered through the help of well-trained enumerators. Data were analysed using simple descriptive statistical tools such as percentages mean score, standard deviation and weighted mean. Findings indicated that they were more male in the both States (55.3% and 57.8%) for Ebonyi and Imo State respectively and that the average age of AEP in Ebonyi and Imo States were 44.7 years and 49.2 years respectively. It was further revealed that the majority (77.3% and 82.8%) had ***./HND as their highest academic qualifications, belonged to professional organisations (62.1% and 75%), and were earning an average monthly income of N58,798 and N62,648 for Ebonyi and Imo State respectively. Also, it was revealed that their mean years of service were 12.4 years and 13.4 years for Ebonyi and Imo State respectively. Almost all of them (87.9% and 95.0%) own a smartphone, had access to the internet (80.3% and 90.0%), but do not own a laptop/ipad (82.6% and 72.8%) for Ebon-yi and Imo State respectively. Results further revealed that Agricultural extension personnel in both Ebonyi and Imo State respectively had low digital literacy level ( = 2.41 and 2.32). The study concluded that AEP in Ebonyi and Imo State respectively had similar socioeconomic characteristics and low level of digital literacy. The study

关键词： Agricultural Extension Personnel Digital Literacy Ebonyi State Imo State Socioeconomic Characteristics

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Consistency features and fuzzy-based segmentation for shadow and reflection detection in digital image forgery

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Science China(Information Sciences) 2017年第8期60卷 83-100页

作者： Rajan CRISTIN Velankanni cyril RAJ St.Peter’s Institute of Higher Education and Research Dr.M.G.R Educational and Research Institute University

Advances in photo editing software have made it possible to generate visually convincing photographic forgeries which have been increased tremendously in recent years. In order to alleviate the problem of image forgery, a handful of techniques have been presented in the literature to detect forgery either in shadow or reflection. This paper aims to develop a technique to detect the image forgery either in shadow or reflection using features enabled neural network. The proposed technique of image forgery detection contains three important steps, like segmentation, feature extraction and detection. In segmentation, shadow points and reflection points are identified using map-based segmentation and FCM clustering. Then, feature points from the shadow points and reflective parts are extracted by considering texture consistency and strength consistency using LVP operator. The final step of forgery detection is performed using the feed forward neural network, where a new algorithm called ABCLM is developed for training of neural network weights. The performance is analyzed with four existing algorithms using measures such as accuracy and MSE. From the analysis, we understand that the proposed technique obtained the maximum accuracy of 80.49%.

关键词： image forensics forgery detection shadow reflection texture neural network

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Restricted Boltzmann machine: Recent advances and mean-field theory

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Chinese Physics B 2021年第4期30卷 1-24页

作者： Aurélien Decelle cyril Furtlehner Departamento de Fìsica Téorica I Universidad Complutense28040 MadridSpain TAU team INRIA Saclay&LISN UniversitéParis Saclay Orsay 91405France

This review deals with restricted Boltzmann machine(RBM) under the light of statistical *** RBM is a classical family of machine learning(ML) models which played a central role in the development of deep *** it as a spin glass model and exhibiting various links with other models of statistical physics,we gather recent results dealing with mean-field theory in this *** the functioning of the RBM can be analyzed via the phase diagrams obtained for various statistical ensembles of RBM,leading in particular to identify a compositional phase where a small number of features or modes are combined to form complex *** we discuss recent works either able to devise mean-field based learning algorithms;either able to reproduce generic aspects of the learning process from some ensemble dynamics equations or/and from linear stability arguments.

关键词： restricted Boltzmann machine(RBM) machine learning statistical physics

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Sensing of physiological regulators by innate lymphoid cells

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Cellular & Molecular Immunology 2019年第5期16卷 442-451页

作者： cyril Seillet Nicolas Jacquelot Molecular Immunology Division Walter and Eliza Hall Institute of Medical ResearchMelbourneVIC 3052Australia Department of Medical Biology University of MelbourneMelbourneVIC 3010Australia

Maintenance of homeostasis and immune protection rely on the coordinated action of different physiological *** communication between the immune system and physiological systems is required to sense and restore any disruption of *** transcriptomic analyses of innate lymphoid cells(ILCs)from different tissues have revealed that ILCs express a large array of receptors involved in the recognition of neuropeptides,hormones and metabolic *** rapidly secrete effector cytokines that are central in the development and activation of early immune responses,but they also constitutively secrete mediators that are important for tissue *** achieve these functions effectively,ILCs integrate intrinsic and extrinsic signals that modulate their constitutive and induced *** of the regulation of ILCs by physiological regulators leads to altered immune responses with harmful consequences for the *** understanding of these complex interactions between the immune system and physiological mediators is crucial to decipher the events leading to the protective versus pathological effects of these cells.

关键词： innate lymphoid cells immunity immune protection homeostasis

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