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The benefits and dangers of using artificial intelligence in petrophysics

Artificial Intelligence in Geosciences 2021年第1期2卷 1-10页

作者： steve Cuddy Petrophysicist Petro-InnovationsAberdeenScotlandUnited Kingdom

Artificial Intelligence,or AI,is a method of data analysis that learns from data,identify patterns and makes predictions with the minimal human *** is bringing many benefits to petrophysical *** case studies,this paper describes several successful *** future of AI has even more ***,if used carelessly there are potentially grave consequences.A complex Middle East Carbonate field needed a bespoke shaly water saturation *** was used to‘evolve’an ideal equation,together with field specific saturation and cementation *** UKCS gas field had an‘oil problem’.Here,AI was used to unlock the hidden fluid information in the NMR T1 and T2 spectra and successfully differentiate oil and gas zones in real time.A North Sea field with 30 wells had shear velocity data(Vs)in only 4 *** was required for reservoir modelling and well bore stability *** was used to predict Vs in all 30 *** high vertical resolution data,the Vs predictions were even better than the recorded *** it is not economic to take core data on every well,AI is used to discover the relationships between logs,core,litho-facies and permeability in multi-dimensional data *** a consequence,all wells in a field were populated with these data to build a robust reservoir *** addition,the AI predicted data upscaled correctly unlike many conventional *** gives impressive results when automatically log quality controlling(LQC)and repairing electrical logs for bad hole and sections of missing *** doesn’t require prior knowledge of the petrophysical response equations and is *** are no parameters to pick or cross-plots to *** is very little user intervention and AI avoids the problem of‘garbage in,garbage out’(GIGO),by ignoring noise and *** programs work with an unlimited number of electrical logs,core and gas chromatography data;and don’t‘fall-over’if some of those inp

关键词： Artificial intelligence Fuzzy logic Petrophysics

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Introduction to Visual Surveillance of Dynamic Scenes

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自动化学报 2003年第3期29卷 319-320页

作者： steve Maybank DepartmentofComputerScience

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The Commutator of the Kato Square Root for Second Order Elliptic Operators on R^n

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Acta Mathematica Sinica,English Series 2016年第10期32卷 1121-1144页

作者： Yan Ping CHEN Yong DING steve HOFMANN Department of Applied Mathematics School of Mathematics and PhysicsUniversity of Science and Technology Beijing School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex Systems(BNU)Ministry of Education Department of Mathematics University of Missouri

Let L = -div（AV） be a second order divergence form elliptic operator, and A be an accretive, n × n matrix with bounded measurable complex coefficients in R^n. We obtain the Lp bounds for the commutator generated by the Kato square root v/L and a Lipschitz function, which recovers a previous result of Calderon, by a different method. In this work, we develop a new theory for the commutators associated to elliptic operators with Lipschitz function. The theory of the commutator with Lipschitz function is distinguished from the analogous elliptic operator theory.

关键词： Commutator Kato square root Lipschitz function elliptic operators

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Compacted graphite iron-A material solution for modern diesel engine cylinder blocks and heads

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China Foundry 2009年第3期6卷 241-246页

作者： steve Dawson SinterCast Sweden

The demands for improved fuel economy,performance and emissions continue to pose challenges for engine designers and the materials they choose. This is particularly true for modern diesel engines,where the primary path to achieving improved engine performance and emissions is to increase the Peak Firing Pressure in the combustion chamber. The resulting increase in thermal and mechanical loading has required a change from conventional grey cast iron to Compacted Graphite Iron (CGI) in order to satisfy durability requirements without increasing the size or the weight of the engines. With at least 75% higher tensile strength,45% higher stiffness and approximately double the fatigue strength of conventional grey cast iron,CGI satisfies durability requirements and also provides the dimensional stability required to meet emissions legislation throughout the life of the engine. Currently,there are no CGI diesel engines running on the roads in North America. This is set to change considerably as new commercial vehicle and pick-up SUV diesel engines are launched with CGI cylinder blocks in 2008 and 2009. These initial programs will provide over 2 million CGI diesel engines when ramped to mature volume,potentially accounting for 10%-15% of the North American passenger vehicle fleet within the next four years.

关键词： compacted graphite iron modern diesel engine performance emission cylinder blocks and heads

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Projecting the global impact of fossil fuel production from the Former Soviet Union

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International Journal of Coal Science & Technology 2021年第6期8卷 1208-1226页

作者： steve Mohr Jianliang Wang James Ward Damien Giurco The University of Newcastle University DriveCallaghanNSW 2308Australia School of Business Administration China University of PetroleumBeijingChina Engineering and the Environment University of South AustraliaMawson Lakes CampusMawson Lakes BoulevardMawson LakesSA 5095Australia Institute for Sustainable Futures University of Technology SydneyUTS Building 10235 Jones St.UltimoNSW 2007Australia

Detailed projections of the Former Soviet Union(FSU)fossil fuel production has been *** production has been modelled at the region(oblast)level where *** projections were made using the Geologic Resource Supply-Demand Model(GeRS-DeMo).Low,Best Guess and High scenarios were *** fossil fuels are projected to peak between 2027 and 2087 with the range due to spread of Ultimately Recoverable Resources(URR)values *** Best Guess(BG)scenario anticipates FSU will peak in 2087 with production over 170 EJ per *** FSU projections were combined with rest of the world projections(Mohr et al.2015b),the emissions from the High scenario for the world are similar to the IPCC A1 AIM scenario.

关键词： Former Soviet Union Fossil Fuel Production Fossil Fuel Projection

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Thermal-responsive genetic and epigenetic regulation of DAM cluster controlling dormancy and chilling requirement in peach floral buds

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Horticulture Research 2020年第1期7卷 1276-1289页

作者： Hong Zhu Pao-Yang Chen Silin Zhong Chris Dardick Ann Callahan Yong-Qiang An steve van Knocker Yingzhen Yang Gan-Yuan Zhong Albert Abbott Zongrang Liu USDA-ARS Appalachian Fruit Research StationKearneysvilleWV 25430USA Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China Institute of Plant and Microbial Biology Academia SinicaTaipei 11529Taiwan The State Key Laboratory of Agrobiotechnology School of Life ScienceThe Chinese University of Hong KongHong KongHong Kong USDA-ARS Plant Genetics Research UnitDonald Danforth Plant Science CenterSt LouisMO 63132USA Department of Horticulture Michigan State UniversityEast LansingMI 48834USA USDAARS Grape Genetic Research UnitGenevaNY 14456USA Forest Health Research and Education Center University of KentuckyLexingtonKY 40546USA

The Dormancy-associated MADS-box(DAM)gene cluster in peach serves as a key regulatory hub on which the seasonal temperatures act and orchestrate dormancy onset and exit,chilling response and floral bud developmental ***,how different temperature regimes interact with and regulate the six linked DAM genes remains ***,we demonstrate that chilling downregulates DAM1 and DAM3–6 in dormant floral buds with distinct patterns and identify DAM4 as the most abundantly expressed *** reveal multiple epigenetic events,with tri-methyl histone H3 lysine 27(H3K27me3)induced by chilling specifically in DAM1 and DAM5,a 21-nt sRNA in DAM3 and a ncRNA induced in *** induction is inversely correlated with downregulation of their cognate *** also show that the six DAMs were hypermethylated,associating with the production of 24-nt ***,the chilling-responsive dynamic of the different epigenetic elements and their interactions likely define distinct expression abundance and downregulation pattern of each *** further show that the expression of the five DAMs remains steadily unchanged or continuously downregulated at the ensuing warm temperature after chilling,and this state of regulation correlates with robust increase of sRNA expression,H3K27me3 and CHH methylation,which is particularly pronounced in *** robust increase of repressive epigenetic marks may irreversibly reinforce the chillingimposed repression of DAMs to ensure flower-developmental programming free from any residual DAM *** together,we reveal novel information about genetic and epigenetic regulation of the DAM cluster in peach,which will be of fundamental significance in understanding of the regulatory mechanisms underlying chilling requirement and dormancy release,and of practical application for improvement of plasticity of flower time and bud break in fruit trees to adapt changing climates.

关键词： epigenetic cluster chilling

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PTOX Mediates Novel Pathways of Electron rransport in Etioplasts of Arabidopsis

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Molecular Plant 2016年第9期9卷 1240-1259页

作者： Sekhar Kambakam Ujjal Bhattacharjee Jacob Petrich steve Rodermel Department of Genetics Development and Cell Biology iowa State University 445 Bessey Hall Ames IA 50011 USA Department of Chemistry Iowa State University Ames IA 50011 USA

The immutans （im） variegation mutant of Arabidopsis defines the gene for PTOX （plastid terminal oxidase）, a versatile plastoquinol oxidase in chloroplast membranes. In this report we used im to gain insight into the function of PTOX in etioplasts of dark-grown seedlings. We discovered that PTOX helps control the redox state of the plastoquinone （PQ） pool in these organelles, and that it plays an essential role in etioplast metabolism by participating in the desaturation reactions of carotenogenesis and in one or more redox pathways mediated by PGR5 （PROTON GRADIENT REGULATION 5） and NDH （NAD（P）H dehydrogenase）, both of which are central players in cyclic electron transport. We propose that these elements couple PTOX with electron flow from NAD（P）H to oxygen, and by analogy to chlororespiration （in chloroplasts） and chromorespiration （in chromoplasts）, we suggest that they define a respiratory process in etioplasts that we have termed ＂etiorespiration＂. We further show that the redox state of the PQ pool in etioplasts might control chlorophyll biosynthesis, perhaps by participating in mechanisms of retrograde （plastid- to-nucleus） signaling that coordinate biosynthetic and photoprotective activities required to poise the etioplast for light development. We conclude that PTOX is an important component of metabolism and redox sensing in etioplasts.

关键词： immutans PTOX etiorespiration phytoene prochlorophyllide retrograde singnaling

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Fourier coefficients of restrictions of eigenfunctions

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Science China Mathematics 2023年第8期66卷 1849-1878页

作者： Emmett L.Wyman Yakun Xi steve Zelditch Department of Mathematics University of RochesterRochesterNY 14627USA School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics Northwestern UniversityEvanstonIL 60208USA

Let{e_(j)}be an orthonormal basis of Laplace eigenfunctions of a compact Riemannian manifold(M,g).Let H■M be a submanifold and{ψ_(k)}be an orthonormal basis of Laplace eigenfunctions of H with the induced *** obtain joint asymptotics for the Fourier coefficientsL^(2)(H)=∫He_(j),ψ_(k)dV_(H)of restrictionsγHe_(j)of e_(j)to *** particular,we obtain asymptotics for the sums of the norm-squares of the Fourier coefficients over the joint spectrum{(μ_(k),λ_(j))}^(∞)_(j,k-0)of the(square roots of the)Laplacian△_(M)on M and the Laplacian△_(H)on H in a family of suitably‘thick'regions in R^(2).Thick regions include(1)the truncated coneμ_(k)/λ_(j)∈[a,b]■(0,1)andλ_(j)≤λ,and(2)the slowly thickening strip|μ_(k)-cλ_(j)|≤w(λ)andλ_(j)≤λ,where w(λ)is monotonic and 1■w(λ)≤λ^(1/2).Key tools for obtaining the asymptotics include the composition calculus of Fourier integral operators and a new multidimensional Tauberian theorem.

关键词： eigenfunctions period integrals Kuznecov formula

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A Variable Stiffness Soft Gripper Using Granular Jamming and Biologically Inspired Pneumatic Muscles

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Journal of Bionic Engineering 2018年第2期15卷 236-246页

作者： Loai AI Abeach Samia Nefti-Meziani Theo Theodoridis steve Davis Autonomous Systems and Robotics Research Centre University of Salford Salford M5 4WT UK Computer Engineering Department College of Engineering Basra University Basra 61004 Iraq

As the domains, in which robots operate change the objects a robot may be required to grasp and manipulate, are likely to vary sig- nificantly and often. Furthermore there is increasing likelihood that in the future robots will work collaboratively alongside people. There has therefore been interest in the development of biologically inspired robot designs which take inspiration from nature. This paper pre- sents the design and testing of a variable stiffness, three fingered soft gripper, which uses pneumatic muscles to actuate the fingers and granular jamming to vary their stiffness. This gripper is able to adjust its stiffness depending upon how fragile/deformable the object being grasped is. It is also lightweight and low inertia, making it better suited to operation near people. Each finger is formed from a cylindrical rubber bladder filled with a granular material. It is shown how decreasing the pressure inside the finger increases the jamming effect and raises finger stiffness. The paper shows experimentally how the finger stiffness can be increased from 21 N·m^-1 to 71 N·m^-1. The paper also describes the kinematics of the fingers and demonstrates how they can be position-controlled at a range of different stiffness values.

关键词： biologically inspired robots variable stiffness actuation soft robotics soft grippers pneumatic muscles

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A review of the formulation and application of the spatial equilibrium models to analyze policy

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Journal of Forestry Research 2011年第4期22卷 671-679页

作者： Phan Sy Hieu steve Harrison The Centre for Informatics and Statistics Ministry of Agriculture and Rural Development in Vietnam No. 2 Ngoc Ha Street Ba Dinh district Hanoi Vietnam Associate Professor the School of Economics the University of Queensland Australia.

This paper reviews alternative market equilibrium models for policy analysis. The origin of spatial equilibrium models and their application to wood and wood-processing industries are described. Three mathematical programming models commonly applied to solve spatial problems - namely linear programming, non-linear programming and mixed complementary programming - are reviewed in terms of forms of objective functions and constraint equalities and inequalities. These programming are illustrated with numerical examples. Linear programming is only applied in transportation problems to solve quantities trans, ported between regions when quantities supplied and demanded in each region are already known. It is argued that linear programming can be applied in broader context to transportation problems where supply and demand quantities are unknown and are linear. In this context, linear programming is seen as a more convenient method for modelers because it has a simpler objective function and does not require as strict conditions, for instance the equal numbers of variables and equations required in mixed complementary programming. Finally, some critical insights are provided on the interpretation of optimal solutions generated by solving spatial equilibrium models.

关键词： simplex method reduced-gradient linear programming non-linear programming mixed complementary programming

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