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World Journal of Gastroenterology 2021年第17期27卷 1936-1942页

作者： Maxim s petrov school of Medicine The University of AucklandAuckland 1142New Zealand

progress in the fight against pancreatic cancer has been hampered by many *** of them is the inability to detect the disease early in overwhelming majority of *** present paper outlines a novel way in which progress could be *** includes a focus on two harbingers—post-pancreatitis diabetes mellitus and excess intra-pancreatic fat deposition—that converge at affecting the tumor macroenvironment and microenvironment specifically in the pancreas,not other *** two entities have the potential to be incorporated into future screening strategies with a view to early detecting of pancreatic cancer.

关键词： pancreatic cancer post-pancreatitis diabetes mellitus Intra-pancreatic fat pancreatitis Early detection screening

Central Asia—A Global Model for the Formation of Epigenetic Deposits in a platform sedimentary Cover

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Journal of Earth science 2022年第2期33卷 278-288页

作者： Igor pechenkin Vladislav petrov FsBI All-Russian scientific-Research Institute of Mineral Resources MoscowRussia Institute of Geology of Ore Deposits petrography Mineralogy and Geochemistry RAs MoscowRussia

Metallogenic specialization of sedimentary cover in Central Asia is determined by its tectonic setting that governs the hydrodynamic regime(exfiltrational or infiltrational)and as a consequence,the hydrogeochemical zonality(type of water and its gaseous and microcomponent composition).Hydrodynamic conditions(distribution of recharge and discharge areas)determine the direction of stratal water flow and location of mineralization resulted from the change in geochemical,thermodynamic,lithological,structural and other *** exfiltrational regime suggests a dependence of the epigenetic mineralization upon the distribution and degree of preservation of hydrocarbon ***,hydrocarbon matter serves as a reducing barrier and ore-concentrating factor during the formation of polymineral concentrations related to stratal oxidation *** supergene epigenetic ore-forming processes are induced by the interaction between the Earth’s sedimentary cover and *** rocks themselves commonly serve as a source of ore *** ore deposition zones on geochemical barriers and ore material source are often located significantly apart from each *** trend of these processes is determined by the position of ore-bearing depressions in large tectonic blocks.

关键词： Central Asia Kyzyl Kum Bukantau ore-forming systems epigenetic ore deposit geology

Optimal control of natural resources in mining industry

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International Journal of Mining science and Technology 2015年第2期25卷 193-198页

作者： petrov Nikolay Tanev Angel Electrical Engineering Electronics and AutomationTechnical University-Sofia Faculty of Mathematics and Informatics Sofia University

The paper focuses on the optimal control of natural resources in mining industry. The purpose is to pro- pose an optimal extraction series of these resources during the lifetime of the Mine＇s maintenance. Fol- lowing the proposed optimal control model, a sensitivity analysis has been performed that includes the interest rate impact on the optimal solution. This study shows that the increasing of the interest rate sti- mulates faster extraction of the resources. The discounting factor induces that the resource has to be extracted faster hut this effect is counterbalanced by the diminishing returns of the annual cash flow. At higher parameters of ＂alpha＂ close to one of the power function about 80% from the whole resource will be extracted during the first 4 years of object/mine maintenance. An existence of unique positive root with respect to return of investment has been proposed and proved by two ways： by the ＂method of chords＂ and by using specialized software.

关键词： Optimal control Natural resources Interest rate sensitivity analysis Method of chords

Diversity considerations in wideband radar detection of migrating targets in clutter

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science China(Information sciences) 2019年第4期62卷 31-40页

作者： Franois LE CHEVALIER Nikita petrov Department Microwave sensing Signals and Systems (MS3) Delft University of Technology

Wideband radars have been proposed for detection of moving targets, with unique capability of non-ambiguous detection due to range migration. Moreover, frequency diversity has long been used for mitigating the fading effects caused by target and clutter fluctuations. The real benefits of wideband radars are difficult to analyze, since they derive from the combined effects of target resolution in range, migration over successive cells of clutter, Doppler resolution and instantaneous bandwidth, and residual ambiguities in Doppler. In order to contribute to a better understanding of the benefits of agile transmissions for detection of moving targets, clutter cancelling performances of wideband radars are examined, demonstrating clear benefits from diversity on clutter and target, primarily – but not only – obtained through target migration effects. special attention is given to long-range surveillance and tracking, and new results on detection of moving targets in clutter will be provided to demonstrate the effectiveness of these new architectures for small targets detection at long range, in difficult environments. Finally, recommendations for system designs that improve the discrimination of moving targets against fixed and diffuse clutter are presented.

关键词： radar extended target frequency diversity wideband detection target migration clutter cancelling

sol-gel synthesis, surface and magnetic properties of nanocrystalline smAlO_3

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Journal of Rare Earths 2010年第4期28卷 602-605页

作者： Dimitar petrov Bogdan Angelov Vasil Lovchinov Department of Inorganic and physical Chemistry University of Food Technologies 26 Maritsa Blvd. 4002 Plovdiv Bulgaria Institute of solid state physics Bul garian Academy of Sciences 72Tzarigradsko Chaussee Blvd. 1784 Sofia Bulgaria

Nanocrystals of single-phase samarium monoaluminate (smAlO3) were synthesized and studied for the first time. Malic acid was employed as a new complexing agent in the sol-gel process. The material was characterized by X-ray diffraction (XRD), scanning electron microscopy (sEM), energy-dispersive X-ray analysis (EDs), specific surface area and density. The lowest size of the nanoparticles was about 50–60 nm and some of them formed agglomerates. The binding energies of core-level electrons of sm (3d, 4d, 4f, ...

关键词： smAlO3 nanocrystals surface properties magnetic susceptibility rare earths

Extension of Near-Wall Domain Decomposition to Modeling Flows with Laminar-Turbulent Transition

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Communications in Computational physics 2022年第2期31卷 645-668页

作者： M.petrov s.Utyuzhnikov A.Chikitkin N.smirnova Moscow Institute of physics&Technology Dolgoprudny 141700Russia Department of Mechanical Aerospace&Civil EngineeringThe University of ManchesterManchesterM139PLUK

The near-wall domain decomposition method(NDD)has proved to be very efficient for modeling near-wall fully turbulent *** this paper the NDD is extended to non-equilibrium regimeswith laminar-turbulent transition(LTT)for the first *** LTT is identified with the use of the e^(N)-method which is applied to both incompressible and compressible *** ismodified to take into account LTT in an *** addition,implementation of the intermittency expands the capabilities of NDD to model non-equilibrium turbulent flows with *** of the modified NDD approach is demonstrated on various test problems of subsonic and supersonic flows past a flat plate,a supersonic flow over a compression corner and a planar shock wave impinging on a turbulent boundary *** results of modeling with and without decomposition are compared in terms of wall friction and show good agreement with each other while NDD significantly reducing computational resources *** turns out that the NDD can reduce the computational time as much as three times while retaining practically the same accuracy of prediction.

关键词： Domain decomposition laminar-turbulent transition interface boundary condition near-wall flow low-Reynolds-number model

Evaluation of Energy saving Operational Modes for Industrial Fracture Connected processes on the Basis of Incubation Time Fracture Criterion

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Transactions of Tianjin University 2008年第B10期14卷 476-482页

作者： Bratov Vladimir petrov Yuri InstituteofproblemsofMechanicalEngineering 199178St.-PetersburgRussia st.-petersburgstateUniversity 198504St.-PetersburgRussia

A problem for a central crack in a plate subjected to plane strain conditions is investigated. Mode I crack loading is created by a dynamic pressure pulse applied at a large distance from the crack. It was found that for a certain combination of amplitude and duration of the pulse applied, the energy transmitted to the sample has a strongly marked minimum, meaning that with the pulse amplitude or duration moving away from the optimal values, minimum energy required for initiation of crack growth increases rapidly. The results obtained indicate a possibility to optimise energy consumption of different industrial processes connected with fracture. Much could be gained in, for example, drilling or rock pounding where energy input accounts for the largest part of the process cost. presumably further investigation of the effect observed can make it possible to predict optimal energy saving parameters, i.e. frequency and amplitude of impacts, for industrial devices, e.g. bores, grinding machines, and hence significantly reduce the process cost. The pre- diction can be given based on the parameters of the media fractured （material parameters, prevalent crack length and orientation, etc.）.

关键词： fracture energy saving incubation time fracture criterion

Development of Zeff diagnostic system on the Globus-M（M2） tokamak and the first experimental results

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plasma science and Technology 2019年第10期21卷 33-39页

作者： E A TUKHMENEVA s Yu TOLsTYAKOV G s KURsKIEV V K GUsEV V B MINAEV Yu V petrov N V sAKHAROV A Yu TELNOVA N N BAKHAREV p B sHEGOLEV E O KIsELEV Ioffe Institute

studying the behavior of effective ion charge Zeff, which indicates the degree of pollution of plasma and can provide valuable information about many processes taking place in plasma, mechanisms of the releasing impurities, transport, etc is of great interest. This paper describes the development of the Zeff diagnostic system for the Globus-M2 tokamak. The effective ion charge is determined on the basis of measurements of the bremsstrahlung intensity and Thomson scattering data-Te and ne profiles. The results of the first Zeff measurements obtained for several discharges on the Globus-M tokamak are presented in this paper. The results have been validated by simulation using the AsTRA transport code for the same discharges, and it has demonstrated a good agreement with the experimental results.

关键词： tokamak effective ion charge magnetic confinement

plasmon-assisted optical trapping and anti-trapping

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Light(science & Applications) 2016年第1期5卷 52-57页

作者： Aliaksandra Ivinskaya Mihail I petrov Andrey A Bogdanov Ivan shishkin pavel Ginzburg Alexander s shalin Department of Nanophotonics and Metamaterials ITMO UniversityBirzhevaja Line14199034 St PetersburgRussia school of Electrical Engineering Tel Aviv UniversityRamat AvivTel Aviv 69978Israel Kotel’nikov Institute of Radio Engineering and Electronics of Russian Academy of sciences(Ulyanovsk branch) Goncharova Street 48/2432071 UlyanovskRussia Ulyanovsk state University Lev Tolstoy Street 42432017 UlyanovskRussia

The ability to manipulate small objects with focused laser beams has opened a venue for investigating dynamical phenomena relevant to both fundamental and applied *** and plasmonic structures enable superior performance in optical trapping via highly confined *** this case,the interplay between the excitation field,re-scattered fields and the eigenmodes of a structure can lead to remarkable effects;one such effect,as reported here,is particle trapping by laser light in a vicinity of metal *** plasmon excitation at the metal substrate plays a key role in tailoring the optical forces acting on a nearby *** on whether the illuminating Gaussian beam is focused above or below the metal-dielectric interface,an order-of-magnitude enhancement or reduction of the trap stiffness is achieved compared with that of standard glass ***,a novel plasmon-assisted anti-trapping effect(particle repulsion from the beam axis)is predicted and studied.A highly accurate particle sorting scheme based on the new anti-trapping effect is *** ability to distinguish and configure various electromagnetic channels through the developed analytical theory provides guidelines for designing auxiliary nanostructures and achieving ultimate control over mechanical motion at the microand nano-scales.

关键词： Gaussian beam Green’s function optical forces optical tweezers surface plasmon