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A new class of generalized quasi-variational inequalities with applications to Oseen problems under nonsmooth boundary conditions

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Science China mathematics 2024年第2期67卷 315-338页

作者： Shengda Zeng Akhtar A.Khan stanislaw migórski Guangxi Colleges and Universities Key Laboratory of Complex System Optimization and Big Data Processing Yulin Normal UniversityYulin 537000China Faculty of mathematics and Computer Science Jagiellonian University in Krak´owKrak´ow 30348Poland Center for Applied and Computational mathematics School of Mathematical SciencesRochester Institute of TechnologyRochesterNY 14623USA College of Sciences Beibu Gulf UniversityQinzhou 535000China

In this paper, we study a generalized quasi-variational inequality (GQVI for short) with twomultivalued operators and two bifunctions in a Banach space setting. A coupling of the Tychonov fixedpoint principle and the Katutani-Ky Fan theorem for multivalued maps is employed to prove a new existencetheorem for the GQVI. We also study a nonlinear optimal control problem driven by the GQVI and givesufficient conditions ensuring the existence of an optimal control. Finally, we illustrate the applicability of thetheoretical results in the study of a complicated Oseen problem for non-Newtonian fluids with a nonmonotone andmultivalued slip boundary condition (i.e., a generalized friction constitutive law), a generalized leak boundarycondition, a unilateral contact condition of Signorini’s type and an implicit obstacle effect, in which themultivalued slip boundary condition is described by the generalized Clarke subgradient, and the leak boundarycondition is formulated by the convex subdifferential operator for a convex superpotential.

关键词： generalized quasi-variational inequality existence theorem optimal control Kakutani-Ky Fan theorem Oseen problem non-Newtonian fluid nonmonotone slip boundary condition

Gas-dynamic phenomena caused by rock mass tremors and rock bursts

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International Journal of mining Science and Technology 2020年第3期30卷 413-420页

作者： stanislaw Wasilewski The Strata mechanics Research Institute of the Polish Academy of Science ul.Reymonta 2730-059 KrakowPoland

Similar to coal, rock and gas ejections, rock mass tremors and rock bursts are among the most serious natural hazards accompanying the underground extraction of coal. Gas-dynamic phenomena caused by rock mass tremors and rock bursts observed as transient states of air parameters in mining headings,are usually generated as a result of a change in the geometry of headings and the release of considerable amounts of gases. Particular significance is attributed to transient states caused by disasters, which are often accompanied by rapid incidents, presenting threats to the life and health of the underground *** Polish mining there are known examples of transient states of air parameters recorded during gasdynamic phenomena, e.g. tremors and rock bursts. The paper presents the case studies of rapid seismic incidents to show how records in mine monitoring systems broaden the knowledge about the transient states of air parameters in mining headings generated because of them.

关键词： Rock mass tremors Rock bursts Gas-dynamic phenomena Transient states of air parameters mine monitoring systems

Heparin improves organ microcirculatory disturbances in caerulein-induced acute pancreatitis in rats

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World Journal of Gastroenterology 2004年第17期10卷 2553-2556页

作者： marek dobosz Lucjanna mionskowska stanislaw Ha■ Sebastian Dobrowolski Dariusz Dymecki Zdzislaw Wajda Department of General and Gastroenterological Surgery St.Vincent a'Paulo HospitalGdyniaPoland Department of General Transplant and Endocrine SurgeryMedical University of Gda■skPoland

AIm:microcirculatory disturbances are important early pathophysiological events in various organs during acute *** aim of the study was to evaluate changes in microperfusion of the pancreas,liver,kidney,stomach, colon,skeletal muscle,and to investigate the influence of heparin on the organ microcirculation in caerulein-induced experimental acute pancreatitis. mETHODS:Acute pancreatitis was induced by 4 intraperitoneal injections of caerulein(Cn)(15 μg/kg).The organ microcirculation was measured by laser Doppler *** interleukin 6 and hematocrit levels were analysed. RESULTS:Acute pancreatitis resulted in a significant drop of microperfusion in all examined *** administration(2×2.5 mg/kg)improved the microcirculation in pancreas(36.9±4% vs 75.9±10%),liver(56.6±6% vs 75.2±16%),kidney (45.1±6% vs 79.3±5%),stomach (65.2±8% vs 78.1±19%),colon(69.8±6% vs 102.5±19%), and skeletal muscle (59.2±6% vs 77.9±13%).Heparin treatment lowered IL-6(359.0±66 U/mL vs 288.5±58 U/mL) and hematocrit level(53±4% vs 46±3%). CONCLUSION:Heparin administration has a positive influence on organ microcirculatory disturbances accompanying experimental Cn-induced acute pancreatitis.

关键词： Acute Disease Animals Anticoagulants Caerulein Hematocrit Heparin male microcirculation Pancreas Pancreatitis Rats Rats, Wistar Research Support, Non-U.S. Gov't Splanchnic Circulation

Uncertainty in public health models treated by differential inclusions

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International Journal of modeling, Simulation, and Scientific Computing 2020年第4期11卷 224-236页

作者： stanislaw Raczynski Faculty of Engineering Universidad Panamericana Augusto Rodin No.49803920 Mexico CityD.F.Mexico

An application of differential inclusions in the epidemic spread models is *** mostly used epidemic models are discussed here,and a brief survey of epidemic modeling is *** of the models are some modifications of the Susceptible–Infected–Recovered *** simulations are carried ***,we consider the influence of some uncertain *** is pointed out that the presence of some fluctuating model parameters can be treated by differential *** solution to such differential inclusion is given in the form of reachable sets for model ***,we focus on the differential inclusion application rather than the model construction.

关键词： modeling simulation epidemics public health sensitivity differential inclusions.

Designing coal panels in the conditions of associated methane and spontaneous fire hazards

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International Journal of mining Science and Technology 2020年第4期30卷 525-531页

作者： stanislaw Prusek Eugeniusz Krause Jacek Skiba Central mining Institute Katowice 40-166Poland

An increase in methane,spontaneous fire and bumping hazards in Polish hard coal mines,observed in the last two decades,led to the need to elaborate the tools allowing proper selection of a range of preventive measures to fight them at the stage of designing coal *** the production of a coal seams in the conditions of associated methane and spontaneous fires hazards in Polish hard coal mines requires elaboration of the design standards for coal panels in gassy coal *** paper presents the guidelines on how to design production in the conditions of associated methane and spontaneous fire *** tools and methodology since the very first research were many times verified by daily mining operations in the conditions of associated methane and spontaneous fire hazards,which confirms their significant contribution to the development of safe and economical mining operations.

关键词： Coal exploitation methane Spontaneous fires Associated hazards Designing coal panels Ventilation

Simultaneous events, singularity in the space of models and chicken game

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International Journal of modeling, Simulation, and Scientific Computing 2021年第4期12卷 1-11页

作者： stanislaw Raczynski Facultad de Ingenier´ıa Universidad Panamericana Augusto Rodin 498Ciudad de M´exico 03920M´exico

The discrete event simulation with simultaneous events is *** models are treated as some points in the general space of *** main topic of this paper is the convergence of sequences of continuous models to the corresponding discrete event *** is pointed out that the discrete event models may represent some singularities in the space of *** fact is related to the problem of validity of discrete event *** models presented here are not the topic of the *** are known models,used as *** model of the“chicken game”and multiple elastic collisions are *** is shown that if a discrete event model is some special limit case of a sequence of continuous models with finite event duration,then that limit model is a *** may provide results very different from the expected limit value of the results from the converging sequence of models.

关键词： Simulation discrete events modeling

mIXED VARIATIONAL INEQUALITIES DRIVEN BY FRACTIONAL EVOLUTIONARY EQUATIONS

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Acta mathematica Scientia 2019年第2期39卷 461-468页

作者： stanislaw mIGóRSKI Shengda ZENG College of Sciences Beibu Gulf University Jagiellonian University in Krakow Faculty of mathematics and Computer Science Jagiellonian University in Krakow

The goal of the present paper is to investigate an abstract system, called fractional differential variational inequality, which consists of a mixed variational inequality combined with a fractional evolution equation in the framework of Banach spaces. Using discrete approximation approach, an existence theorem of solutions for the inequality is established under some suitable assumptions.

关键词： fractional differential variational inequality C_0-semigroup minty mixed variational inequality existence mild solutions

Chlorophyll extraction from leaves,needles and microalgae:A kinetic approach

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International Journal of Agricultural and Biological Engineering 2013年第2期6卷 107-115页

作者： Krystian miazek stanislaw Ledakowicz Department of Bioprocess Engineering Technical University of Lodz90-924LodzPoland

Currently,there is a strong focus on industrial production of chlorophyll as a natural *** factors are required in the economically feasible process to make chlorophyll production:material with high pigment content and efficient extraction *** this work,extraction of chlorophyll from harvested black locust(Robinia pseudoacacia)leaves,Scots pine(Pinus sylvestris)needles,field sow thistle(Sonchus arvensis)leaves,and green microalga(Chlorella sp.)was *** highest pigment content was detected in Chlorella cells(4.46%)followed by black locust leaves(1.63%),sow thistle leaves(1.48%)and pine needles(0.38%).The chlorophyll extraction rate was the highest for black locust leaves(k=3.59 h^(-1)),sow thistle leaves(k=2.90 h^(-1))and Chlorella cells(k=2.80 h^(-1))with the use of methanol as a *** investigated materials,needles showed higher resistance for chlorophyll extraction(k=0.93 h^(-1))when compared to leaves and *** of extraction kinetic constant were much lower for all materials(0.22-1.12 h^(-1))in the case of using ethanol as a *** locust leaves and Chlorella cells were proved to be the most attractive materials for chlorophyll production.

关键词： chlorophyll extraction leaves needles microalgae kinetic approach

Characterization of multiphase gas–solid flow and accuracy of turbulence models for lower stage cyclones used in suspension preheaters

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1618-1629页

作者： marek Wasilewski stanislaw Anweiler maciej masiukiewicz Faculty of Production Engineering and Logistics Opole University of Technology76 Proszkowska St.45-758 OpolePoland Faculty of mechanical Engineering Opole University of Technology76 Proszkowska St.45-758 OpolePoland

This study involved the analysis and characterization of the multiphase flow phenomenon inside the lower stage cyclone separator used in the clinker burning *** analysis was performed using both CFD and experimental research *** few studies are devoted to such types of cyclone separators,which in addition to their basic functions are also responsible for the technological *** to the atypical working conditions of these cyclone separators,they are characterized with a complex geometry,which significantly differs from that of the traditional ***,the evaluation of the accuracy and level of reliability of the two models of turbulence closure—k-e RNG and RSm(RANS),and the *** results obtained led to the conclusion that for the lower stage cyclone separators,the LES model proved to be the most accurate(both in the case of forecasting the separation efficiency and pressure drop).The performance parameter(in particular the separation efficiency)values obtained for the RSm model were also characterized by high *** k-e RNG model was characterized by significantly larger deviations.

关键词： Cyclone separators Separation multiphase flow CFD Pressure drop Clinker burning