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Optimal Feedback Control of Oil Reservoir Waterflooding Processes

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International Journal of Automation and computing 2016年第1期13卷 73-80页

作者： A.s.Grema Yi Cao school of Energy Environment & Agrifood Cranfield University

Waterfiooding is a process where water is injected into an oil reservoir to supplement its natural pressure for increment in productivity. The reservoir properties are highly heterogeneous, its states change as production progresses which require varying injection and production settings for economic recovery. As water is injected into the reservoir, more oil is expected to be produced. There is also likelihood that water is produced in association with the oil. The worst case is when the injected water meanders through the reservoir, it bypasses pools of oil and gets produced, Therefore, any effort geared toward finding the optimal settings to maximize the value of this venture can never be over emphasized. Waterflooding can be formulated as an optimal control problem. However, traditional optimal control is an open-loop solution, hence cannot cope with various uncertainties inevitably existing in any practical systems. Reservoir models are highly uncertain. Its properties are known with some degrees of certainty near the well-bore region only. In this work, a novel data-driven approach for control variable （CV） selection was proposed and applied to reservoir waterflooding process for a feedback strategy resulting in optimal or near optimal operation. The results indicated that the feedback control method was close to optimal in the absence of uncertainty. The loss recorded in the value of performance index, net present value （NPV） was only 0.26%. Furthermore, the new strategy performs better than the open-loop optimal control solution when system/model mismatch was considered. The performance depends on the scale of the uncertainty introduced. A gain in NPV as high as 30.04% was obtained.

关键词： Oil reservoir management intelligent wells optimal control theory feedback control geological uncertainty.

sIMULATION OF THE TWIN ROLL sTAINLEss sTRIP CAsTING PROCEss

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Acta Metallurgica sinica(English Letters) 2001年第3期14卷 199-204页

作者： Y.C. Miao, X.M. Zhang, G.d. Wang, H.s. di and X.H. Liu (state Key Laboratory of Rolling and Automation, Northeastern University, shenyang 110004, China) state Key Laboratory of Rolling and Automation Northeastern University

The position of the solidification completed temperature of twin roll stainless strip casting process is very important to the quality of the casting strip. In order to control this position, the solidification completed temperature should be known at first. The present paper first simulated dendritic microsegregation under conditions of twin roll stainless strip casting, and got the relationship between the temperature and the solid fraction of the mush zone. The temperatures such as ZdT (equal to the solidification completed temperature) and LIT (liquid impenetrable temperature), et al., also can be found from this relationship. Then by using the turbulent model, the flow and thermal fields of the pool of the twin roll stainless strip casting and the speed and temperature fields of different casting speeds were given and also explained. The simulation results are coincident with the experimental results. Combined with the results of these simulations, the appropriated casting speed was found.

关键词： Computer simulation Continuous casting segregation (metallography) stainless steel Turbulence

Human endogenous retroviruses and cancer:Causality and therapeutic possibilities

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World Journal of Gastroenterology 2012年第42期18卷 6027-6035页

作者： Christina s Mullins Michael Linnebacher department of General ThoracicVascular and Transplantation SurgerySection Molecular Oncology and ImmunotherapyUniversity of RostockSchillingallee 3518057 RostockGermany

A substantial part of the human genome is derived from transposable elements;remnants of ancient retroviral *** estimates set the percentage of human endogenous retroviruses(HERVs) in the genome at 8%.For the most part,the interplay between mutations,epigenetic mechanisms and posttranscriptional regulations silence HERVs in somatic *** first highlight mechanisms by which activation of members of several HERV families may be associated with tumor development before discussing the arising chances for both diagnosis and *** has been shown that at least in some cases,tumor cells expressing HERV open reading frames(ORFs) thus gain tumor-promoting ***,since these proteins are not expressed in healthy tissues,they become prime target *** potential pharmacological interest are the prevention of HERV transposition,the inhibition of HERV-encoded protein expression and the interference with these proteins' *** from recent studies unequivocally proves that HERV ORFs represent a very interesting source of novel tumor-specific antigens with even the potential to surpass entity *** development of new tumor(immune-) therapies is a very active field and true tumor-specific targets are of outstanding interest since they minimize the risk of autoimmunity and could reduce side ***,we postulate on main future research streams in order to stimulate discussion on this hot topic.

关键词： Human endogenous retroviruses Gastro-intestinal cancer Therapeutic targets Tumor-specificantigens Tumorigenesis

sTUdY OF THE EFFECT OF BORON CONTENT ON THE ORdEREd EXTENT OF THE Ni_3Al INTERMETALLICs COMPOUNd BY AP-FIM

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Acta Metallurgica sinica(English Letters) 2000年第4期13卷 1001-1011页

作者： d.G. Ren Z.Q. Li X.s. Fan and J. T. Guo Laboratory of Atomic Imaging of solids, Institute of Metal Research, The Chinese Academy of sciences, shenyang 110015, China Inst of Metal Research Chinese Acad of Sciences Shenyang China

By using AP-FIM the varity of the ordered degree of Ni_3Al with L1_2 structure with B content was studied. The possibility of boron improving ductility was also discussed from bonding between Ni and Al atoms, and antisite defects in Ni_3Al. The extent of ordering is reduced with an increase in boron content and the autisite defects are most obvious for 0.52at.K B-doped sample that has the best ductility. some results were verified by X-ray diffraction non. The addition of boron not only influences electron environment at grain boundary but also in the interior of Ni_3Al gm ins, the latter is favorable to improve the ductility of Ni_3Al grains.

关键词： intermetallic compound AP-FIM effect of boron

MHd flow of a viscous fluid on a nonlinear porous shrinking sheet with homotopy analysis method

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Applied Mathematics and Mechanics(English Edition) 2009年第12期30卷 1569-1578页

作者： s. Nadeem Anwar Hussain department of Mathematics Quaid-i-Azam University

The present paper investigates the magnetohydrodynamic（MHd） flow of a viscous fluid towards a nonlinear porous shrinking *** governing equations are simplified by similarity *** reduced problem is then solved by the homotopy analysis *** pertinent parameters appearing in the problem are discussed graphically and presented in *** is found that the shrinking solutions exist in the presence of *** is also observed from the tables that the solutions for f（0） with different values of parameters are convergent.

关键词： MHd flow stagnation flow shrinking sheet homotopy analysis method

NEW HYBRId CONJUGATE GRAdIENT METHOd As A CONVEX COMBINATION OF Ls ANd FR METHOds

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Acta Mathematica scientia 2019年第1期39卷 214-228页

作者： sne?ana s.dJORdJEVI? Faculty of Technology University of Nis

In this paper, we present a new hybrid conjugate gradient algorithm for unconstrained optimization. This method is a convex combination of Liu-storey conjugate gradient method and Fletcher-Reeves conjugate gradient method. We also prove that the search direction of any hybrid conjugate gradient method, which is a convex combination of two conjugate gradient methods, satisfies the famous d-L conjugacy condition and in the same time accords with the Newton direction with the suitable condition. Furthermore, this property doesn't depend on any line search. Next, we also prove that, moduling the value of the parameter t,the Newton direction condition is equivalent to dai-Liao conjugacy *** strong Wolfe line search conditions are *** global convergence of this new method is *** comparisons show that the present hybrid conjugate gradient algorithm is the efficient one.

关键词： hybrid conjugate gradient method convex combination dai-Liao conjugacy condition Newton direction

spaces of vector-valued dirichlet series in a half plane

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Frontiers of Mathematics in China 2014年第6期9卷 1239-1252页

作者： Akanksha G.s. sRIVAsTAVA department of Mathematics Jaypee Institute of Information TecnologyNOIDA-201307 Uttar Pradesh India

dirichlet series with real frequencies which represent entire functions on the complex plane C have been investigated by many authors. several properties such as topological structures, linear continuous functionals, and bases have been considered. Le Hai Khoi derived some results with dirichlet series having negative real frequencies which represent holomorphic functions in a half plane. In the present paper, we have obtained some properties of holomorphic dirichlet series having positive exponents, whose coefficients belong to a Banach algebra.

关键词： Vector-valued dirichlet series abscissa of convergence norm,topology

Male infertility microsurgical training

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Asian Journal of Andrology 2013年第1期15卷 61-66页

作者： Akanksha Mehta Philip s Li Center for Male Reproductive Medicine and Microsurgery Cornell Institute for Reproductive Medicine Department of Urology Weill Cornell Medical College New York NY10065 USA

Microsurgical training is imperative for urologists and clinical andrologists specializing in male infertility. success in male infertility microsurgery is heavily dependent on the surgeon＇s microsurgical skills. Laboratory-based practice to enhance microsurgical skills improves the surgeon＇s confidence, and reduces stress and operating time, benefiting both the patient and the surgeon. This review provides guidelines for setting up a microsurgical laboratory to develop and enhance microsurgical skills using synthetic and animal models. The role of emerginE techniaues, such as robotic-assisted microsureerv, is also discussed.

关键词： laboratory male infertility microsurgery training vasoepididymostomy vasovasostomy

dirac Equation and some Quasi-Exact solvable Potentials in the Turbiner's Classification

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Communications in Theoretical Physics 2013年第9期60卷 296-302页

作者： s.Aghaei A.Chenaghlou department of Physics Faculty of SciencesSahand University of Technology

In this paper quasi-exact solvability （QEs） of dirac equation with some scalar potentials based on s/（2） Lie algebra is studied. According to the quasi-exact solvability theory, we construct the configuration of the classes II, IV, V, and X potentials in the Turbiner＇s classification such that solved and the Bethe ansatz equations are derived in order to the dirac equation with scalar potential is quasi-exactly obtain the energy eigenvalues and eigenfunctions.

关键词： dirac equation quasi-exact solvability supersymmetric quantum mechanics