Pump-probe differential reflection and transmission spectroscopy is a very effective tool to study the nonequilibrium carrier dynamics of graphene. The reported sign of differential reflection from graphene is not exp...Pump-probe differential reflection and transmission spectroscopy is a very effective tool to study the nonequilibrium carrier dynamics of graphene. The reported sign of differential reflection from graphene is not explicitly explained and not consistent. Here, we study the differential reflection and transmission signals of graphene on a dielectric substrate. The results reveal the sign of differential reflection changes with the incident direction of the probe beam with respect to the substrate. The obtained theory can be applied to predict the differential signals of other two-dimensional materials placed on various dielectric substrates.展开更多
We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed proces...We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed process,are considered.Under certain conditions,we prove the strong consistency and the asymptotic normality of the two estimators.Our method is also suitable for one-sided reflected stochastic differential equations.Simulation results demonstrate that the performance of our estimator is superior to that of the estimator proposed by Cholaquidis et al.(Stat Sin,2021,31:29-51).Several real data sets of the currency exchange rate are used to illustrate our proposed methodology.展开更多
Differential reflectance spectroscopy(DRS)is a powerful tool to study processes during thin-film growth,especially that of transition metal dichalcogenides and organic thin films.To satisfy the requirements for in sit...Differential reflectance spectroscopy(DRS)is a powerful tool to study processes during thin-film growth,especially that of transition metal dichalcogenides and organic thin films.To satisfy the requirements for in situ and real-time monitoring of film growth,including spectral resolution and sensitivity at the level of monolayers and even sub-monolayers,the most challenging technical task in DRS is to reduce noise to an extremely low level so that the best possible signal-to-noise ratio can be achieved.In this paper,we present a simplified and cost-effective DRS apparatus,with which we show that the measurement noise is mainly composed of thermal drift noise and explore the temperature-dependence of the DRS signal.Based on the results obtained,we propose an easily realized and effective scheme aiming to reduce the noise.Experimental results demonstrate that this scheme is effective in stabilizing reliable signals for a long period of several hours.Significant noise reduction is achieved,with the typical average noise of the DRS system being decreased to 0.05%over several hours.The improved DRS system is applied to study the growth of an organic semiconductor layer for an organic field-effect transistor device.The results indicate that the apparatus proposed in this paper has potential applications in fabrication of devices on the nanoscale and even the sub-nanoscale.展开更多
In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations (RBSDEs). We will establish the d...In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations (RBSDEs). We will establish the dynamic programming principle for the upper and the lower value functions of this kind of stochastic differential games with reflection in a straightforward way. Then the upper and the lower value functions are proved to be the unique viscosity solutions to the associated upper and the lower Hamilton-Jacobi-Bettman-Isaacs equations with obstacles, respectively. The method differs significantly from those used for control problems with reflection, with new techniques developed of interest on its own. Further, we also prove a new estimate for RBSDEs being sharper than that in the paper of E1 Karoui, Kapoudjian, Pardoux, Peng and Quenez (1997), which turns out to be very useful because it allows us to estimate the LP-distance of the solutions of two different RBSDEs by the p-th power of the distance of the initial values of the driving forward equations. We also show that the unique viscosity solution to the approximating Isaacs equation constructed by the penalization method converges to the viscosity solution of the Isaacs equation with obstacle.展开更多
To characterize the Neumann problem for nonlinear Fokker-Planck equations,we investigate distribution dependent reflecting stochastic differential equations(DDRSDEs)in a domain.We first prove the well-posedness and es...To characterize the Neumann problem for nonlinear Fokker-Planck equations,we investigate distribution dependent reflecting stochastic differential equations(DDRSDEs)in a domain.We first prove the well-posedness and establish functional inequalities for reflecting stochastic differential equations with singular drifts,and then extend these results to DDRSDEs with singular or monotone coefficients,for which a general criterion deducing the well-posedness of DDRSDEs from that of reflecting stochastic differential equations is established.展开更多
Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D material...Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle solids.This remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon strain.However,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification troubles.In this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D materials.This approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation strategy.Our results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.展开更多
In this paper, we study the reflected solutions of one-dimensional backward stochastic differential equations driven by G-Brownian motion. The reflection keeps the solution above a given stochastic process. In order t...In this paper, we study the reflected solutions of one-dimensional backward stochastic differential equations driven by G-Brownian motion. The reflection keeps the solution above a given stochastic process. In order to derive the uniqueness of reflected G-BSDEs, we apply a "martingale condition" instead of the Skorohod condition. Similar to the classical case, we prove the existence by approximation via penalization. We then give some applications including a generalized Feynman-Kac formula of an obstacle problem for fully nonlinear partial differential equation and option pricing of American types under volatility uncertainty.展开更多
In this paper, we study one-dimensional reflected backward doubly stochastic differential equations (RBDSDEs) with one continuous barrier and discontinuous (left or right continuous) genera- tor. We obtain an exis...In this paper, we study one-dimensional reflected backward doubly stochastic differential equations (RBDSDEs) with one continuous barrier and discontinuous (left or right continuous) genera- tor. We obtain an existence theorem and a comparison theorem for solutions of the class of RBDSDEs.展开更多
In this paper,it is shown that the differential reflectivity Z_(DR) is related to drop size distribution(DSD)and the spectral shape variation of different truncated diameters.Z_(DR) is a sensitive function to variatio...In this paper,it is shown that the differential reflectivity Z_(DR) is related to drop size distribution(DSD)and the spectral shape variation of different truncated diameters.Z_(DR) is a sensitive function to variation of DSD of the spectra.The effects of shape variation of DSD on rainfall can be deduced with a(Z_H,Z_(DR))dual-parameter technique,which is effective to improve the accuracy of rainfall measurement and is of the priority of identifying large particles of hydrometeors(especially hailstone)from the rain region.展开更多
In this paper, we derive the continuous dependence on the terminal condition of solutions to nonlinear reflected backward stochastic differential equations involving the subdifferential operator convex function under ...In this paper, we derive the continuous dependence on the terminal condition of solutions to nonlinear reflected backward stochastic differential equations involving the subdifferential operator convex function under non-Lipschitz of a lower semi-continuous, proper and condition by means of the corollary of Bihari inequality.展开更多
Single-layer MoS_(2)produced by mechanical exfoliation is usually connected to thicker and multilayer regions.We show a facile laser trimming method to insulate single-layer MoS_(2)regions from thicker ones.We demonst...Single-layer MoS_(2)produced by mechanical exfoliation is usually connected to thicker and multilayer regions.We show a facile laser trimming method to insulate single-layer MoS_(2)regions from thicker ones.We demonstrate,through electrical characterization,that the laser trimming method can be used to pattern single-layer MoS_(2)channels with regular geometry and electrically disconnected from the thicker areas.Scanning photocurrent microscope further confirms that in the as-deposited flake(connected to a multilayer area)most of the photocurrent is being generated in the thicker flake region.After laser trimming,scanning photocurrent microscopy shows how only the single-layer MoS_(2)region contributes to the photocurrent generation.The presented method is a direct-write and lithography-free(no need of resist or wet chemicals)alternative to reactive ion etching process to pattern the flakes that can be easily adopted by many research groups fabricating devices with MoS_(2) and similar twodimensional materials.展开更多
Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS_(2),MoSe_(2),WS_(2) and WSe_(2).In this work we provide a thorough description of the technical de...Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS_(2),MoSe_(2),WS_(2) and WSe_(2).In this work we provide a thorough description of the technical details to perform uniaxial strain measurements on these two-dimensional semiconductors and we provide a straightforward calibration method to determine the amount of applied strain with high accuracy.We then employ reflectance spectroscopy to analyze the strain tunability of the electronic properties of single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2) and WSe_(2).Finally,we quantify the flake-to-flake variability by analyzing 15 different single-layer MoS_(2) flakes.展开更多
As a study on exploiting and popularizing the advanced dual-polarization weather radar technique in China,the physical mechanism for the propagation effect of the radar wave is discussed by using the widely adapted ex...As a study on exploiting and popularizing the advanced dual-polarization weather radar technique in China,the physical mechanism for the propagation effect of the radar wave is discussed by using the widely adapted extended boundary condition method,and some theoretic results are provided for improving rain measurement accuracy.Furthermore,phase information, another important characteristic quantity of microwave,is considered for tapping the potentialities of the new meteorological radar system.展开更多
In this short note we consider reflected backward stochastic differential equations(RBSDEs)with a Lipschitz driver and barrier processes that are optional and right lower semicontinuous.In this case,the barrier is rep...In this short note we consider reflected backward stochastic differential equations(RBSDEs)with a Lipschitz driver and barrier processes that are optional and right lower semicontinuous.In this case,the barrier is represented as a nondecreasing limit of right continuous with left limit(RCLL)barriers.We combine some well-known existence results for RCLL barriers with comparison arguments for the control process to construct solutions.Finally,we highlight the connection of these RBSDEs with standard RCLL BSDEs.展开更多
We prove several existence and uniqueness results for Lp (p 〉 1) solutions of reflected BSDEs with continuous barriers and generators satisfying a one-sided Osgood condition together with a general growth condition...We prove several existence and uniqueness results for Lp (p 〉 1) solutions of reflected BSDEs with continuous barriers and generators satisfying a one-sided Osgood condition together with a general growth condition in y and a uniform continuity condition or a linear growth condition in z. A necessary and sufficient condition with respect to the growth of barrier is also explored to ensure the existence of a solution. And, we show that the solutions may be approximated by the penalization method and by some sequences of solutions of reflected BSDEs. These results are obtained due to the development of those existing ideas and methods together with the application of new ideas and techniques, and they unify and improve some known works.展开更多
We consider in this paper random batch interacting particle methods forsolving the Poisson-Nernst-Planck (PNP) equations, and thus the Poisson-Boltzmann(PB) equation as the equilibrium, in the external unbounded domai...We consider in this paper random batch interacting particle methods forsolving the Poisson-Nernst-Planck (PNP) equations, and thus the Poisson-Boltzmann(PB) equation as the equilibrium, in the external unbounded domain. To justify thesimulation in a truncated domain, an error estimate of the truncation is proved inthe symmetric cases for the PB equation. Then, the random batch interacting particle methods are introduced which are O(N) per time step. The particle methods cannot only be considered as a numerical method for solving the PNP and PB equations,but also can be used as a direct simulation approach for the dynamics of the chargedparticles in solution. The particle methods are preferable due to their simplicity andadaptivity to complicated geometry, and may be interesting in describing the dynamics of the physical process. Moreover, it is feasible to incorporate more physical effectsand interactions in the particle methods and to describe phenomena beyond the scopeof the mean-field equations.展开更多
基金supported by the Chinese National Key Basic Research Special Fund (2011CB922003)International Science and Technology Cooperation Program of China (2013DFA51430)+1 种基金NSFC—National Natural Science Foundation of China (11174159, 11374164, 11304166)the Fundamental Research Funds for the Central Universities (65145005)
文摘Pump-probe differential reflection and transmission spectroscopy is a very effective tool to study the nonequilibrium carrier dynamics of graphene. The reported sign of differential reflection from graphene is not explicitly explained and not consistent. Here, we study the differential reflection and transmission signals of graphene on a dielectric substrate. The results reveal the sign of differential reflection changes with the incident direction of the probe beam with respect to the substrate. The obtained theory can be applied to predict the differential signals of other two-dimensional materials placed on various dielectric substrates.
基金partially supported by the National Natural Science Foundation of China(11871244)the Fundamental Research Funds for the Central Universities,JLU。
文摘We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed process,are considered.Under certain conditions,we prove the strong consistency and the asymptotic normality of the two estimators.Our method is also suitable for one-sided reflected stochastic differential equations.Simulation results demonstrate that the performance of our estimator is superior to that of the estimator proposed by Cholaquidis et al.(Stat Sin,2021,31:29-51).Several real data sets of the currency exchange rate are used to illustrate our proposed methodology.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2017YFF0107003).
文摘Differential reflectance spectroscopy(DRS)is a powerful tool to study processes during thin-film growth,especially that of transition metal dichalcogenides and organic thin films.To satisfy the requirements for in situ and real-time monitoring of film growth,including spectral resolution and sensitivity at the level of monolayers and even sub-monolayers,the most challenging technical task in DRS is to reduce noise to an extremely low level so that the best possible signal-to-noise ratio can be achieved.In this paper,we present a simplified and cost-effective DRS apparatus,with which we show that the measurement noise is mainly composed of thermal drift noise and explore the temperature-dependence of the DRS signal.Based on the results obtained,we propose an easily realized and effective scheme aiming to reduce the noise.Experimental results demonstrate that this scheme is effective in stabilizing reliable signals for a long period of several hours.Significant noise reduction is achieved,with the typical average noise of the DRS system being decreased to 0.05%over several hours.The improved DRS system is applied to study the growth of an organic semiconductor layer for an organic field-effect transistor device.The results indicate that the apparatus proposed in this paper has potential applications in fabrication of devices on the nanoscale and even the sub-nanoscale.
基金supported by the Agence Nationale de la Recherche (France), reference ANR-10-BLAN 0112the Marie Curie ITN "Controlled Systems", call: FP7-PEOPLE-2007-1-1-ITN, no. 213841-2+3 种基金supported by the National Natural Science Foundation of China (No. 10701050, 11071144)National Basic Research Program of China (973 Program) (No. 2007CB814904)Shandong Province (No. Q2007A04),Independent Innovation Foundation of Shandong Universitythe Project-sponsored by SRF for ROCS, SEM
文摘In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations (RBSDEs). We will establish the dynamic programming principle for the upper and the lower value functions of this kind of stochastic differential games with reflection in a straightforward way. Then the upper and the lower value functions are proved to be the unique viscosity solutions to the associated upper and the lower Hamilton-Jacobi-Bettman-Isaacs equations with obstacles, respectively. The method differs significantly from those used for control problems with reflection, with new techniques developed of interest on its own. Further, we also prove a new estimate for RBSDEs being sharper than that in the paper of E1 Karoui, Kapoudjian, Pardoux, Peng and Quenez (1997), which turns out to be very useful because it allows us to estimate the LP-distance of the solutions of two different RBSDEs by the p-th power of the distance of the initial values of the driving forward equations. We also show that the unique viscosity solution to the approximating Isaacs equation constructed by the penalization method converges to the viscosity solution of the Isaacs equation with obstacle.
基金supported by the National Key R&D Program of China(Grant No.2020YFA0712900)National Natural Science Foundation of China(Grant Nos.11831014 and 11921001)。
文摘To characterize the Neumann problem for nonlinear Fokker-Planck equations,we investigate distribution dependent reflecting stochastic differential equations(DDRSDEs)in a domain.We first prove the well-posedness and establish functional inequalities for reflecting stochastic differential equations with singular drifts,and then extend these results to DDRSDEs with singular or monotone coefficients,for which a general criterion deducing the well-posedness of DDRSDEs from that of reflecting stochastic differential equations is established.
基金the European Research Council(ERC)under the European Union's Horizon 2020 research and innovation program(Nos.755655,ERC-StG 2017 project 2DTOPSENSE)the Ministry of Science and Innovation(Spain)through the project PID2020-115566RB-I00+5 种基金the EU FLAG-ERA project To2Dox under the program PCI2019-111893-2H.L.acknowledges the grant from China Scholarship Council(CSC)under No.201907040070Ana B.thanks the ERC Union's Horizon 2020 program(No.851929 StG 2019 project 3DScavengers)the Spanish Ministry of Science and Innovation AEI/10.13039/501100011033(No.PID2019-110430GB-C21)the EU ERDF(FEDER Operational Program(2014-2020)A way of making Europe)and the Consejería de Economía,Conocimiento,Empresas y Universidad de la Junta de Andalucía(Nos.P18-RT-3480,EMERGIA and US-1381057).
文摘Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle solids.This remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon strain.However,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification troubles.In this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D materials.This approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation strategy.Our results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.
基金supported by the Tian Yuan Projection of the National Natural Science Foundation of China(Grant Nos.11526205 and 11626247)the German Research Foundation(DFG)via CRC1283the Lebesgue Center of Mathematics(“Investissements d’aveni”Program)(Grant No.ANR-11-LABX-0020-01)
文摘In this paper, we study the reflected solutions of one-dimensional backward stochastic differential equations driven by G-Brownian motion. The reflection keeps the solution above a given stochastic process. In order to derive the uniqueness of reflected G-BSDEs, we apply a "martingale condition" instead of the Skorohod condition. Similar to the classical case, we prove the existence by approximation via penalization. We then give some applications including a generalized Feynman-Kac formula of an obstacle problem for fully nonlinear partial differential equation and option pricing of American types under volatility uncertainty.
基金Supported by Chinese Natural Science Foundation(Grant No.11271093)the Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20090002110047)
文摘In this paper, we study one-dimensional reflected backward doubly stochastic differential equations (RBDSDEs) with one continuous barrier and discontinuous (left or right continuous) genera- tor. We obtain an existence theorem and a comparison theorem for solutions of the class of RBDSDEs.
基金National Disaster Reduction Foundation(96-020-01-07)of China,KZ 951-B1-405 Western Brilliance of the Chinese Academy of Sciences.
文摘In this paper,it is shown that the differential reflectivity Z_(DR) is related to drop size distribution(DSD)and the spectral shape variation of different truncated diameters.Z_(DR) is a sensitive function to variation of DSD of the spectra.The effects of shape variation of DSD on rainfall can be deduced with a(Z_H,Z_(DR))dual-parameter technique,which is effective to improve the accuracy of rainfall measurement and is of the priority of identifying large particles of hydrometeors(especially hailstone)from the rain region.
基金the Key Science and Technology Project of Ministry of Education (207047)The Research Project for Younger Teacher of Anhui Normal University (no.2006xqn49)+2 种基金The Special Project Grants of Anhui Normal University (2006xzx08)The Project Grants for Ph.D of Anhui Normal UniversityThe Teaching Research Project of Anhui Normal University
文摘In this paper, we derive the continuous dependence on the terminal condition of solutions to nonlinear reflected backward stochastic differential equations involving the subdifferential operator convex function under non-Lipschitz of a lower semi-continuous, proper and condition by means of the corollary of Bihari inequality.
基金Financial supports from the National Natural Science Foundation of China(NSFC)(Nos.62011530438 and 61704129)supported by the Key Research and Development Program of Shaanxi(No.2021KW-02),the fundamental Research Funds for the Central Universities(No.JB211409 and 20109215605)+6 种基金the fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University(No.SKLSP201612)funding by European Research Council(ERC)through the project 2D-TOPSENSE(GA 755655)European Union's Horizon 2020 research and innovation program(Graphene Core2-Graphene-based disruptive technologies(No.881603)Graphene Core3-Graphene-based disruptive technologies(No.956813))EU FLAG-ERA through the project To2Dox(No.JTC-2019-009)the Comunidad de Madrid through the project CAIRO-CM project(No.Y2020/NMT-6661)the Spanish Ministry of Science and Innovation through the project(No.PID2020-118078RB-I00).O.Ç.acknowledges the European Union's Horizon 2020 research and innovation program under the grant agreement 956813(2Exciting).S.P.acknowledges the fellowship PRE2018-084818.
文摘Single-layer MoS_(2)produced by mechanical exfoliation is usually connected to thicker and multilayer regions.We show a facile laser trimming method to insulate single-layer MoS_(2)regions from thicker ones.We demonstrate,through electrical characterization,that the laser trimming method can be used to pattern single-layer MoS_(2)channels with regular geometry and electrically disconnected from the thicker areas.Scanning photocurrent microscope further confirms that in the as-deposited flake(connected to a multilayer area)most of the photocurrent is being generated in the thicker flake region.After laser trimming,scanning photocurrent microscopy shows how only the single-layer MoS_(2)region contributes to the photocurrent generation.The presented method is a direct-write and lithography-free(no need of resist or wet chemicals)alternative to reactive ion etching process to pattern the flakes that can be easily adopted by many research groups fabricating devices with MoS_(2) and similar twodimensional materials.
基金This project has received funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(grant agreement no 755655,ERC-StG 2017 project 2D-TOPSENSE)R.F.acknowledges the support from the Spanish Ministry of Economy,Industry and Competitiveness through a Juan de la Cierva-formación fellowship 2017 FJCI-2017-32919.H.L.acknowledges the grant from China Scholarship Council(CSC)under No.201907040070.
文摘Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS_(2),MoSe_(2),WS_(2) and WSe_(2).In this work we provide a thorough description of the technical details to perform uniaxial strain measurements on these two-dimensional semiconductors and we provide a straightforward calibration method to determine the amount of applied strain with high accuracy.We then employ reflectance spectroscopy to analyze the strain tunability of the electronic properties of single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2) and WSe_(2).Finally,we quantify the flake-to-flake variability by analyzing 15 different single-layer MoS_(2) flakes.
文摘As a study on exploiting and popularizing the advanced dual-polarization weather radar technique in China,the physical mechanism for the propagation effect of the radar wave is discussed by using the widely adapted extended boundary condition method,and some theoretic results are provided for improving rain measurement accuracy.Furthermore,phase information, another important characteristic quantity of microwave,is considered for tapping the potentialities of the new meteorological radar system.
文摘In this short note we consider reflected backward stochastic differential equations(RBSDEs)with a Lipschitz driver and barrier processes that are optional and right lower semicontinuous.In this case,the barrier is represented as a nondecreasing limit of right continuous with left limit(RCLL)barriers.We combine some well-known existence results for RCLL barriers with comparison arguments for the control process to construct solutions.Finally,we highlight the connection of these RBSDEs with standard RCLL BSDEs.
基金Supported by National Natural Science Foundation of China(Grant No.11371362)the Fundamental Research Funds for the Central Universities(Grant No.2012QNA36)
文摘We prove several existence and uniqueness results for Lp (p 〉 1) solutions of reflected BSDEs with continuous barriers and generators satisfying a one-sided Osgood condition together with a general growth condition in y and a uniform continuity condition or a linear growth condition in z. A necessary and sufficient condition with respect to the growth of barrier is also explored to ensure the existence of a solution. And, we show that the solutions may be approximated by the penalization method and by some sequences of solutions of reflected BSDEs. These results are obtained due to the development of those existing ideas and methods together with the application of new ideas and techniques, and they unify and improve some known works.
基金This work is partially supported by the National Key R&D Program of China,Project Number 2021YFA1002800The work of L.Li was partially sponsored by the Strategic Priority Research Program of Chinese Academy of Sciences,Grant No.XDA25010403,and NSFC 11901389,12031013The work of J.-G.Liu was supported by NSF DMS-2106988.
文摘We consider in this paper random batch interacting particle methods forsolving the Poisson-Nernst-Planck (PNP) equations, and thus the Poisson-Boltzmann(PB) equation as the equilibrium, in the external unbounded domain. To justify thesimulation in a truncated domain, an error estimate of the truncation is proved inthe symmetric cases for the PB equation. Then, the random batch interacting particle methods are introduced which are O(N) per time step. The particle methods cannot only be considered as a numerical method for solving the PNP and PB equations,but also can be used as a direct simulation approach for the dynamics of the chargedparticles in solution. The particle methods are preferable due to their simplicity andadaptivity to complicated geometry, and may be interesting in describing the dynamics of the physical process. Moreover, it is feasible to incorporate more physical effectsand interactions in the particle methods and to describe phenomena beyond the scopeof the mean-field equations.