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Ecological Processes 2015年第1期4卷 180-189页

作者： igor Povar Oxana Spinu Institute of Chemistry of Academy of Sciences of Moldova 3 Academiei str.ChişinăuMD 2028Republic of Moldova

The main focus in this review is showing how to use the developed buffer theory for assessing and predicting the long-term phenomena of attenuation and natural remediation of ionic pollutants in contaminated aquatic ecosystems,as well as for analyzing the way by which metals move and transform within the environment,the distribution of metals in ecosystems,their deposition and cycling in the terrestrial *** buffer theory is based on the rigorous thermodynamic analysis of complex chemical equilibria under environmental conditions in aquatic ecosystems,as natural waters and *** has been established that both homogeneous and heterogeneous systems manifest a buffer action towards all their *** buffer properties in relation to the solid phase components are amplified with an increase of solubility due to protolytic or complex formation equilibria in saturated *** has been established that the buffer capacities of components are mutually proportional,whereas for heterogeneous systems these relationships depend on the stoichiometric composition of solid *** use of the developed buffer approach may yield extended knowledge and a deeper understanding of the processes that control the concentrations of components.A number of the important conclusions concerning the investigated buffer systems have been *** obtained results are indented to provide researchers with a tool needed to help them to set reliable limits of ion(metal)levels in the environment.

关键词： Buffer capacity Ecosystem Heterogeneous multicomponent system Proportionality relation between buffer capacities

Chaotic Simulator for Bilevel Optimization of Virtual Machine Placements in Cloud Computing

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Journal of the Operations Research Society of China 2022年第4期10卷 703-723页

作者： Timothy Ganesan Pandian Vasant igor Litvinchev Member of American Mathematical Society AlbertaT2P 0X2Canada Universiti Teknologi Petronas Seri Iskandar32610Malaysia Nuevo Leon State University San Nicolás de los GarzaNuevo LeónCP66450Mexico

The drastic increase in engineering system complexity has spurred the development of highly efficient optimization *** real-world optimization problems have been identified as bilevel/multilevel as well as *** primary aim of this work is to present a framework to tackle the bilevel virtual machine(VM)placement problem in cloud *** is done using the coupled map lattice(CML)approach in conjunction with the Stackelberg game theory and weighted-sum *** VM placement problem was modified from the original multiobjective(MO)problem to an MO bilevel formulation to make it more realistic albeit more *** comparative analysis on the performance of the CML approach was carried out against the particle swarm optimization method.A new bilevel metric called the cascaded hypervolume indicator is introduced and applied to measure the dominance of the solutions produced by both *** analysis on the computational results is presented.

关键词： Bilevel multiobjective Coupled map lattices(CML) Stackelberg game theory Particle swarm optimization(PSO) Cascaded hypervolume indicator(cHVI) Virtual machine(VM)placement

A New Convergent Explicit Tree-Grid Method for HJB Equations in One Space Dimension

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Numerical Mathematics(Theory,Methods and Applications) 2018年第1期11卷 1-29页

作者： igor Kossaczky Matthias Ehrhardt Michael Gunther Lehrstuhl fur Angewandte Mathematik und Numerische Analysis Fakultat fur Mathematik und NaturwissenschaftenBergische Universitat WuppertalGaußstrasse 2042119 WuppertalGermany

In this work we introduce a new unconditionally convergent explicit Tree-Grid Method for solving stochastic control problems with one space and one time dimension or equivalently,the corresponding Hamilton-Jacobi-Bellman *** prove the convergence of the method and outline the relationships to other numerical *** case of vanishing diffusion is treated by introducing an artificial diffusion *** illustrate the superiority of our method to the standardly used implicit finite difference method on two numerical examples from finance.

关键词： Tree-Grid Method Hamilton-Jacobi-Bellman equation Stochastic control problem

Mud volcano origin of the Mottled Zone,South Levant

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Geoscience Frontiers 2013年第5期4卷 597-619页

作者： igor Novikov Yevgeny Vapnik Inna Safonova Institute of Geology and Mineralogy SB RAS Koptuyga Ave.3Novosibirsk 630090Russia Department of Geological and Environmental Sciences Ben-Gurion University of the NegevP.O.B.653Beer-Sheva 84105Israel

The Mottled Zone（MZ） or Hatrurim Formation,which occurs near the Levantine Transform in the South Levant,has been studied during the last 150 years but its origin remains *** Zone Complex/Complexes（MZC/MZCs） consist of brecciated carbonate and low-temperature calcium-hydro-silicate rocks,which include unusual high- and ultra-high-temperature low-pressure（HT-LP） meta-morphic mineral *** MZ has been regarded as a product of combustion of bituminous chalks of the Ghareb *** Cretaceous（Maastrichtian） *** this paper we present detailed geographic, geomorphologic,structural and geological data from the MZCs of the South Levant,which show that the MZCs cannot be stratigraphically correlated with the Ghareb Fm.,because MZC late Oligocene-late Pleistocene deposits occur within or unconformable i.e.,with stratigraphic hiatus,overlap both the late Cretaceous and,in places,Neogene stratigraphic *** propose an alternative model for the formation of MZCs by tectonically induced mud volcanism during late Oligocene-late Pleistocene time. This model explains（i） the presence of dikes and tube-like bodies,which consist of brecciated exotic clastic material derived from stratigraphically and hypsometrically lower horizons;（ii） mineral assemblages of sanidinite facies metamorphism;（iii） multi-stage character of HT-LP pyrometamorphism;and （iv） multi-stage low-temperature hydrothermal *** temperatures（up to 1500℃） mineral assemblages resulted from combustion of hydrocarbon gases of mud *** volcanism was spatially and structurally related to neotectonic folds and deformation zones formed in response to opening of the Red Sea rift and propagation of the Levantine Transform *** model may significantly change the prospects for oil-and-gas deposits in the region.

关键词： HT-LP sanidinite facies metamorphism Geomorphology Dead Sea Levantine Transform Neotectonics Hydrocarbon traps

Domino Tiling:A New Method of Real-Time Conforming Mesh Construction for Rendering Changeable Height Fields

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Journal of Computer Science & Technology 2011年第6期26卷 971-987页

作者： Dorde M. Durdevi igor I. Tartalja School of Electrical Engineering University of Belgrade

In this paper we present a novel GPU-oriented method of creating an inherently continuous triangular mesh for tile-based rendering of regular height fields. The method is based on tiling data-independent semi-regular meshes of non-uniform structure, a technique that is quite different from other mesh tiling approaches. A complete, memory efficient set of mesh patterns is created by an off-line procedure and stored into the graphics adapter＇s memory at runtime. At rendering time, for each tile, one of the precomputed mesh patterns is selected for rendering. The selected mesh pattern fits the required level of details of the tile and ensures seamless connection with other adjacent mesh patterns, like in a game of dominoes. The scalability potential of the proposed method is demonstrated through quadtree hierarchical grouping of tiles. The efficiency is verified by experimental results on height fields for terrain representation, where the method achieves high frame rates and sustained triangle throughput on high resolution viewports with sub-pixel error tolerance. Frame rate sensitivity to real-time modifications of the height field is measured, and it is shown that the method is very tolerant and consequently well tailored for applications dealing with rapidly changeable phenomena represented by height fields.

关键词： graphics data structures and data types height field surface representation level of details real-time heightfield manipulation view-dependent rendering

Comparative geochemical study of the cherty rocks of the Taukha terrane(Sikhote-Alin)and its paleogeodynamic significance

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Acta Geochimica 2020年第4期39卷 539-560页

作者： igor V.Kemkin Raisa A.Kemkina Far East Geological Institute Far Eastern Branch of Russian Academy of SciencesProspect 100-Letiya Vladivostoka159VladivostokRussia 690022 Far Eastern Federal University Soukhanova Street8VladivostokRussia 690950

The article presents the results of a comparative geochemical study of cherts and siliceous-clayey rocks composing the tectono-sedimentary complexes of various structural levels of the Taukha terrain of the Sikhote-Alin Late Jurassic-Early Cretaceous accretionary *** data obtained show that the same-aged parts of the crosssections of the cherty-terrigenous sequences of the terrane lower and middle structural levels are characterized by significantly different contents and distribution patterns of major petrogenic oxides,trace,and rare-earth elements due to their accumulation in various facies of oceanic *** set of geochemical data indicates that the formation of both tectono-sedimentary complexes was carried out differently,gradually replacing each others’facies oceanic zones,and started in the near-spreading ridge area,then in the pelagial,and completed in the continental-margin deposition *** on the time interval of the facies conditions changing for each complex(i.e.,time of transition from one facies zone to another),the speeds of a paleo-oceanic plate motion(and,correspondingly,the speeds of spreading)for individual intervals of the Jurassic were *** in the spreading speeds at various sites of a paleorift zone caused the turning of a paleocontinent margin contour and spreading ridge axis at the perpendicular position,which in turn caused change of the geodynamic mode on the eastern margin of the PaleoAsian continent at the Jurassic-Cretaceous transition.

关键词： Geochemistry Radiolarian cherts Deposition environment Paleo-Pacific plate Sikhote-Alin

Role of quantum dots nanoparticles in the chemical treatment of colored wastewater: Catalysts or additional pollutants

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Journal of Environmental Sciences 2011年第9期23卷 1479-1485页

作者： Hrvoje Kusic Danuta Leszczynska Natalija Koprivanac igor Peterne Civil and Environmental Engineering Department Jackson State University Faculty of Chemical Engineering and Technology University of Zagreb

The objective of the study was to investigate the presence and the activity of quantum dots nanoparticles in colored *** special interest is devoted to the investigation of their role in the typical treatment of water or wastewater,studying their influence on the effectiveness of applied treatments *** standard chemical processes for water treatment and disinfection （direct UV photolysis and direct ozonation） were applied for the degradation of colored organic pollutant,reactive azo dye,in the presence/absence of CdSe/ZnS core-shells quantum *** obtained results indicated that investigated nanoparticles inhibit the overall efficiency of applied processes,especially in the case of direct UV photolysis,although catalytic effect might be expected in part due to the semiconductor nature of quantum *** results lead to a conclusion that CdSe/ZnS nanoparticles behave as additional pollutants in the *** should be removed from the system prior the treatment,because their presence could decrease the efficiency,i.e.,prolong the time of treatment and correspondingly increase the costs of the treatment process.

关键词： wastewater treatment CdSe/ZnS core-shells reactive azo dye UV irradiation ozone

Optimized Filling of a Given Cuboid with Spherical Powders for Additive Manufacturing

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Journal of the Operations Research Society of China 2021年第4期9卷 853-868页

作者： Zoya Duriagina igor Lemishka igor Litvinchev Jose Antonio Marmolejo Alexander Pankratov Tatiana Romanova Georgy Yaskov Lviv Polytechnic National University Lviv 79013Ukraine Katolicki Uniwersytet Lubelski Jana Pawła II Al.Racławickie 1420950 LublinPoland Graduate Program in Systems Engineering Nuevo Leon State University(UANL)MonterreyCP 66455 San Nicolas de los GarzaNuevo LeonMexico Engineering Department Panamerican UniversityCP 03920 Mexico CityMexico Department of Mathematical Modeling and Optimal Design Institute for Mechanical Engineering Problemsthe National Academy of Sciences of UkraineKharkiv 61046Ukraine Department of Systems Engineering of Kharkiv National University of Radio Electronics Kharkiv 61166Ukraine

In additive manufacturing(also known as 3D printing),a layer-by-layer buildup process is used for manufacturing *** laser 3D printers can work with various materials including metal *** particular,mixing various-sized spherical powders of titanium alloys is considered most promising for the aerospace *** achieve desired mechanical properties of the final product,it is necessary to maintain a certain proportional ratio between different powder *** this paper,a modeling approach for filling up a rectangular 3D volume by unequal spheres in a layer-by-layer manner is proposed.A relative number of spheres of a given radius(relative frequency)are known and have to be fulfilled in the final packing.A fast heuristic has been developed to solve this special packing *** results are compared with experimental findings for titanium alloy spherical *** relative frequencies obtained by using the imposed algorithm are very close to those obtained by the *** provides an opportunity for using a cheap numerical modeling instead of expensive experimental study.

关键词： Sphere packing Heuristic algorithm Titanium alloy spherical powders 3D printing

Recording Spatially Resolved Plasma Parameters in Microwave-Driven Plasmas

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Plasma Science and Technology 2013年第1期15卷 43-51页

作者： Gerhard FRANZ Florian SCHAMBERGER igor KRSTEV Stefan UMRATH Munich University of Applied Sciences Munich D-80335

In an almost cubical reactor 90 1 in volume which is intended to deposit organic polymers by plasma-enhanced chemical vapor deposition （PECVD）, microwave power is coupled into the volume via a quartz window which extends to approximately 1/10 of the sidewall area. Since the plasma is excited locally, plasma parameters like electron temperature and plasma density are expected to exhibit a spatial variation. The compilation of these plasma quantities has been accomplished with a bendable single Langmuir probe. To isolate the tungsten wire against its grounded housing tube, it was coated with polyparylene. After having compared this construction with our Langmuir probe, which has been now in use for more than a decade, we have taken data of more than half the volume of the reactor with argon and have found a definitive radial inhomogenity for all plasma parameters. To investigate whether this conduct can be determined applying optical emission spectroscopy, we improved our spectrometer which had been used for endpoint detection purposes and plasma diagnostics in chlorine-containing ambients where we could detect also a spatial dependence. This behavior is discussed in terms of Lieberman＇s global model.

关键词： high frequency and RF discharges optical measurements electric and mag-netic measurements

A novel method for investigation of acoustic and elastic wave phenomena using numerical experiments

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Theoretical & Applied Mechanics Letters 2020年第5期10卷 307-314页

作者： Alena Favorskaya igor Petrov Moscow Institute of Physics and Technology DolgoprudnyMoscow regionRussian Federation Scientific Research Institute for System Analysis of the Russian Academy of Sciences MoscowRussian Federation Xi'an Jiaotong University Xi'an 710049China

The emergence of new types of composite materials,the depletion of existing hydrocarbon deposits,and the increase in the speed of trains require the development of new research methods based on wave ***,it is necessary to determine the laws of wave scattering in inhomogeneous *** propose a method that combines the advantages of a numerical simulation with an analytical study of the boundary value problem of elastic and acoustic wave *** this letter we present the results of the study using the proposed method:the formation of a response from a shear wave in an acoustic medium and the formation of shear waves when a vertically incident longitudinal wave is scattered by a vertical gas-filled *** have obtained a number of analytical expressions characterising the scattering of these wave types.

关键词： Elastic waves Acoustic waves Waves scattering Fractures Seismic prospecting