The following topics are dealt with: data mining; knowledge discovery; intelligent control; fuzzy... more The following topics are dealt with: data mining; knowledge discovery; intelligent control; fuzzy control; hybrid system; adaptive system; neural networks; statistical learning methods; reasoning; learning; agents; distributed artificial intelligence; machine learning; fuzzy information processing; image processing; vision processing; and pattern recognition.
Evolution of a self-consistent joint system (JS), i.e., a quantum system (QS) + thermal bath (TB)... more Evolution of a self-consistent joint system (JS), i.e., a quantum system (QS) + thermal bath (TB), is considered within the framework of the Langevin–Schrödinger (L-Sch) type equation. As a tested QS, we considered two linearly coupled quantum oscillators that interact with TB. The influence of TB on QS is described by the white noise type autocorrelation function. Using the reference differential equation, the original L-Sch equation is reduced to an autonomous form on a random space–time continuum, which reflects the fact of the existence of a hidden symmetry of JS. It is proven that, as a result of JS relaxation, a two-dimensional quantized small environment is formed, which is an integral part of QS. The possibility of constructing quantum thermodynamics from the first principles of non-Hermitian quantum mechanics without using any additional axioms has been proven. A numerical algorithm has been developed for modeling various properties and parameters of the QS and its environm...
Институт космических исследований Российской академии наук (ИКИ РАН), 2015
THREE-DIMENSIONAL TENSOR MATHEMATICS OF COMPUTATIONAL EXPERIMENT IN FLUIDMECHANICS.
A. Bogdano... more THREE-DIMENSIONAL TENSOR MATHEMATICS OF COMPUTATIONAL EXPERIMENT IN FLUIDMECHANICS.
A. Bogdanov, A. Degtyarev, V. Khramushin
Department of Computer Modelling and Multiprocessor Systems,
Faculty of Applied Mathematics and Control Processes of Saint-Petersburg State University
Architecture of a digital computing system determines the technical foundation of a unified mathematical language for exact arithmetic–logical description of phenomena and laws of continuum mechanics for applications in fluid mechanics and physical field theory. Enhancement of modern computers involvs computing operations in optimally formalized set of locally connected digital geometric objects, existing and transforming independently, and being surrounded by similar virtual entities. Deep parallelization of computing processes serves to the revival of application of functional programming at a new technological level, providing traceability of computing processes with automatic application of multiscale hybrid circuits and adaptive mathematical models for the true reproduction of the fundamental laws of physics and continuum mechanics. Tensor formalization of numerical objects and computing operations serves to spatial interpolation of rheological state parameters and laws of the fluid mechanics as mathematical models in the local coordinates of the elementary numeric cells – large liquid particles.
Санкт-Петербургский государственный университет (СПбГУ) факультет Прикладной математики-процессов управления кафедра компьютерного моделирования и многопроцессорных систем
Архитектура цифрового вычислительного комплекса определяет техническую основу унифицированного математического языка для строгого арифметико-логического описания явлений и законов механики сплошных сред для прикладных задач гидромеханики и физической теории поля. Совершенствование современных компьютеров стоит на пути вовлечения
вычислительных операций в весьма вольные формализации множества локально-связных цифровых геометрических объектов, независимо существующих и трансформирующихся в окружении аналогичных виртуальных сущностей, и по совокупности моделирующих реальные взаимодействия смежных частиц сплошной среды. Глубокое распараллеливание вычислительных процессов служит возрождению на новом техническом уровне прикладного функционального программирования, обеспечивающего сквозной контроль вычислительных процессов с автоматическим применением разномасштабных гибридных схем и адаптивных математических моделей для достоверного воспроизведения фундаментальных законов физики и механики сплошных сред. Тензорная формализация числовых объектов и вычисли-
тельных операций служит пространственной интерполяции параметров реологического состояния и законов гидромеханики в качестве математических моделей в локальных координатах элементарных числовых ячеек – крупных частиц жидкости.
The paper deals with the computer implementation of direct computational experiments in fluid mec... more The paper deals with the computer implementation of direct computational experiments in fluid mechanics, constructed on the basis of the approach developed by the authors. The proposed approach allows the use of explicit numerical scheme, which is an important condition for increasing the efficiency of the algorithms developed by numerical procedures with natural parallelism. The paper examines the main objects and operations that let you manage computational experiments and monitor the status of the computation process. Special attention is given to a) realization of tensor representations of numerical schemes for direct simulation; b) realization of representation of large particles of a continuous medium motion in two coordinate systems (global and mobile); c) computing operations in the projections of coordinate systems, direct and inverse transformation in these systems. Particular attention is paid to the use of hardware and software of modern computer systems.
9th International Conference "Distributed Computing and Grid Technologies in Science and Education", 2021
Simulation of the beam dynamics is an important stage in the design and launch of a charged parti... more Simulation of the beam dynamics is an important stage in the design and launch of a charged particle accelerator. To solve this problem, many methods and software packages have been developed.Standard approaches to modeling accelerators require the use of not only ready-made libraries but exact theory and clearly formalized mathematical models. However, now such accelerator systems are emerging, where they plan to study phenomena, the physics of which is not completely clear.Therefore, a new type of accelerator requires a different approach to beam modeling. This article describes an approach to creating a virtual accelerator that will allow simulating particle physics,taking into account the peculiarities of the latest accelerators and the problem of the lack of an accurate theory for various phenomena planned to be detected at the accelerator.
Computational Science and Its Applications – ICCSA 2018, 2018
Modern heterogeneous computer systems offer an exceptional computational potential, but require s... more Modern heterogeneous computer systems offer an exceptional computational potential, but require specific knowledge and experience on the part of the programmer to fully realize it. In this paper we explore different approaches to the task of adapting an application to the heterogeneous computer system. We provide performance evaluation of the test application ported using those approaches. We also evaluate the difficulty and time investment required to implement those approaches in relation to performance improvements they offer.
Modern scientific and business applications often require fast provisioning of an infrastructure ... more Modern scientific and business applications often require fast provisioning of an infrastructure tailored to particular application needs. In turn, actual physical infrastructure contains resources that might be underutilized by applications if allocated in dedicated mode (e.g., a process does not utilize provided CPU or network connection fully). Traditional virtualization technologies can solve the problem partially, however, overheads on bootstrapping a virtual infrastructure for each application and sharing physical resources might be significant. In this paper we propose and evaluate an approach to create and configure dedicated computing environment tailored to the needs of particular applications, which is based on light-weight virtualization also known as containers. We investigate available capabilities to model and create dynamic container-based virtual infrastructures sharing a common set of physical resources, and evaluate their performance on a set of test applications with different requirements.
Stages of direct computational experiments in hydromechanics based on tensor mathematics tools ar... more Stages of direct computational experiments in hydromechanics based on tensor mathematics tools are represented by conditionally independent mathematical models for calculations separation in accordance with physical processes. Continual stage of numerical modeling is constructed on a small time interval in a stationary grid space. Here coordination of continuity conditions and energy conservation is carried out. Then, at the subsequent corpuscular stage of the computational experiment, kinematic parameters of mass centers and surface stresses at the boundaries of the grid cells are used in modeling of free unsteady motions of volume cells that are considered as independent particles. These particles can be subject to vortex and discontinuous interactions, when restructuring of free boundaries and internal rheological states has place. Transition from one stage to another is provided by interpolation operations of tensor mathematics. Such interpolation environment formalizes the use ...
In particle accelerator physics the problem is that we can not see what is going on inside the wo... more In particle accelerator physics the problem is that we can not see what is going on inside the working machine. There are a lot of packages for modelling the behaviour of the particles in numerical or analytical way. But for most physicists it is better to see the picture in motion to say exactly what is happening and how to influence on this. The goal of this work is to provide scientists with such a problem-solving environment, which can not only do some numerical calculations, but show the dynamics of changes as a motion 3D picture. To do this we use the power of graphical processors from both sides: for general purpose calculations and for there direct appointment – drawing 3D motion. Besides, this environment should analyse the behaviour of the system to provide the user with all necessary information about the problem and how to deal with it.
To represent the space charge forces of beam a software based on analytical models for space char... more To represent the space charge forces of beam a software based on analytical models for space charge distributions was developed. Special algorithm for predictor-corrector method for beam map evaluation scheme including the space charge forces were used. This method allows us to evaluate the map along the reference trajectory and to analyze beam envelope dynamics. In three dimensional models the number of computing resources we use is significant. For this purpose graphical processors are used. This software is a part of Virtual Accelerator concept which is considered as a set of services and tools of modeling beam dynamics in accelerators on distributed computing resources.
Analytical and numerical peculiarities of solving nonlinear problems are considered on examples o... more Analytical and numerical peculiarities of solving nonlinear problems are considered on examples of wave equations like KdVB and Kadomtsev-Petviashvili-I equation (KPI). KPI is represented in integro-differential form. Main attention is paid to the problem of asymptotical behavior of solution and appearance of nonphysical artefacts. The numerical solution is carried out by the finite difference method. For a correct representation of the boundary condition along the y axis in numerical simulation a method is proposed for introducing small artificial convection into the original equation in the indicated direction. Along with the introduction of artificial convection, the procedure of trimming of the integral on the bands adjacent to the upper and lower boundaries of the calculated region is used. The results obtained by numerical testing, showed sufficient accuracy and validity of this procedure.
The following topics are dealt with: data mining; knowledge discovery; intelligent control; fuzzy... more The following topics are dealt with: data mining; knowledge discovery; intelligent control; fuzzy control; hybrid system; adaptive system; neural networks; statistical learning methods; reasoning; learning; agents; distributed artificial intelligence; machine learning; fuzzy information processing; image processing; vision processing; and pattern recognition.
Evolution of a self-consistent joint system (JS), i.e., a quantum system (QS) + thermal bath (TB)... more Evolution of a self-consistent joint system (JS), i.e., a quantum system (QS) + thermal bath (TB), is considered within the framework of the Langevin–Schrödinger (L-Sch) type equation. As a tested QS, we considered two linearly coupled quantum oscillators that interact with TB. The influence of TB on QS is described by the white noise type autocorrelation function. Using the reference differential equation, the original L-Sch equation is reduced to an autonomous form on a random space–time continuum, which reflects the fact of the existence of a hidden symmetry of JS. It is proven that, as a result of JS relaxation, a two-dimensional quantized small environment is formed, which is an integral part of QS. The possibility of constructing quantum thermodynamics from the first principles of non-Hermitian quantum mechanics without using any additional axioms has been proven. A numerical algorithm has been developed for modeling various properties and parameters of the QS and its environm...
Институт космических исследований Российской академии наук (ИКИ РАН), 2015
THREE-DIMENSIONAL TENSOR MATHEMATICS OF COMPUTATIONAL EXPERIMENT IN FLUIDMECHANICS.
A. Bogdano... more THREE-DIMENSIONAL TENSOR MATHEMATICS OF COMPUTATIONAL EXPERIMENT IN FLUIDMECHANICS.
A. Bogdanov, A. Degtyarev, V. Khramushin
Department of Computer Modelling and Multiprocessor Systems,
Faculty of Applied Mathematics and Control Processes of Saint-Petersburg State University
Architecture of a digital computing system determines the technical foundation of a unified mathematical language for exact arithmetic–logical description of phenomena and laws of continuum mechanics for applications in fluid mechanics and physical field theory. Enhancement of modern computers involvs computing operations in optimally formalized set of locally connected digital geometric objects, existing and transforming independently, and being surrounded by similar virtual entities. Deep parallelization of computing processes serves to the revival of application of functional programming at a new technological level, providing traceability of computing processes with automatic application of multiscale hybrid circuits and adaptive mathematical models for the true reproduction of the fundamental laws of physics and continuum mechanics. Tensor formalization of numerical objects and computing operations serves to spatial interpolation of rheological state parameters and laws of the fluid mechanics as mathematical models in the local coordinates of the elementary numeric cells – large liquid particles.
Санкт-Петербургский государственный университет (СПбГУ) факультет Прикладной математики-процессов управления кафедра компьютерного моделирования и многопроцессорных систем
Архитектура цифрового вычислительного комплекса определяет техническую основу унифицированного математического языка для строгого арифметико-логического описания явлений и законов механики сплошных сред для прикладных задач гидромеханики и физической теории поля. Совершенствование современных компьютеров стоит на пути вовлечения
вычислительных операций в весьма вольные формализации множества локально-связных цифровых геометрических объектов, независимо существующих и трансформирующихся в окружении аналогичных виртуальных сущностей, и по совокупности моделирующих реальные взаимодействия смежных частиц сплошной среды. Глубокое распараллеливание вычислительных процессов служит возрождению на новом техническом уровне прикладного функционального программирования, обеспечивающего сквозной контроль вычислительных процессов с автоматическим применением разномасштабных гибридных схем и адаптивных математических моделей для достоверного воспроизведения фундаментальных законов физики и механики сплошных сред. Тензорная формализация числовых объектов и вычисли-
тельных операций служит пространственной интерполяции параметров реологического состояния и законов гидромеханики в качестве математических моделей в локальных координатах элементарных числовых ячеек – крупных частиц жидкости.
The paper deals with the computer implementation of direct computational experiments in fluid mec... more The paper deals with the computer implementation of direct computational experiments in fluid mechanics, constructed on the basis of the approach developed by the authors. The proposed approach allows the use of explicit numerical scheme, which is an important condition for increasing the efficiency of the algorithms developed by numerical procedures with natural parallelism. The paper examines the main objects and operations that let you manage computational experiments and monitor the status of the computation process. Special attention is given to a) realization of tensor representations of numerical schemes for direct simulation; b) realization of representation of large particles of a continuous medium motion in two coordinate systems (global and mobile); c) computing operations in the projections of coordinate systems, direct and inverse transformation in these systems. Particular attention is paid to the use of hardware and software of modern computer systems.
9th International Conference "Distributed Computing and Grid Technologies in Science and Education", 2021
Simulation of the beam dynamics is an important stage in the design and launch of a charged parti... more Simulation of the beam dynamics is an important stage in the design and launch of a charged particle accelerator. To solve this problem, many methods and software packages have been developed.Standard approaches to modeling accelerators require the use of not only ready-made libraries but exact theory and clearly formalized mathematical models. However, now such accelerator systems are emerging, where they plan to study phenomena, the physics of which is not completely clear.Therefore, a new type of accelerator requires a different approach to beam modeling. This article describes an approach to creating a virtual accelerator that will allow simulating particle physics,taking into account the peculiarities of the latest accelerators and the problem of the lack of an accurate theory for various phenomena planned to be detected at the accelerator.
Computational Science and Its Applications – ICCSA 2018, 2018
Modern heterogeneous computer systems offer an exceptional computational potential, but require s... more Modern heterogeneous computer systems offer an exceptional computational potential, but require specific knowledge and experience on the part of the programmer to fully realize it. In this paper we explore different approaches to the task of adapting an application to the heterogeneous computer system. We provide performance evaluation of the test application ported using those approaches. We also evaluate the difficulty and time investment required to implement those approaches in relation to performance improvements they offer.
Modern scientific and business applications often require fast provisioning of an infrastructure ... more Modern scientific and business applications often require fast provisioning of an infrastructure tailored to particular application needs. In turn, actual physical infrastructure contains resources that might be underutilized by applications if allocated in dedicated mode (e.g., a process does not utilize provided CPU or network connection fully). Traditional virtualization technologies can solve the problem partially, however, overheads on bootstrapping a virtual infrastructure for each application and sharing physical resources might be significant. In this paper we propose and evaluate an approach to create and configure dedicated computing environment tailored to the needs of particular applications, which is based on light-weight virtualization also known as containers. We investigate available capabilities to model and create dynamic container-based virtual infrastructures sharing a common set of physical resources, and evaluate their performance on a set of test applications with different requirements.
Stages of direct computational experiments in hydromechanics based on tensor mathematics tools ar... more Stages of direct computational experiments in hydromechanics based on tensor mathematics tools are represented by conditionally independent mathematical models for calculations separation in accordance with physical processes. Continual stage of numerical modeling is constructed on a small time interval in a stationary grid space. Here coordination of continuity conditions and energy conservation is carried out. Then, at the subsequent corpuscular stage of the computational experiment, kinematic parameters of mass centers and surface stresses at the boundaries of the grid cells are used in modeling of free unsteady motions of volume cells that are considered as independent particles. These particles can be subject to vortex and discontinuous interactions, when restructuring of free boundaries and internal rheological states has place. Transition from one stage to another is provided by interpolation operations of tensor mathematics. Such interpolation environment formalizes the use ...
In particle accelerator physics the problem is that we can not see what is going on inside the wo... more In particle accelerator physics the problem is that we can not see what is going on inside the working machine. There are a lot of packages for modelling the behaviour of the particles in numerical or analytical way. But for most physicists it is better to see the picture in motion to say exactly what is happening and how to influence on this. The goal of this work is to provide scientists with such a problem-solving environment, which can not only do some numerical calculations, but show the dynamics of changes as a motion 3D picture. To do this we use the power of graphical processors from both sides: for general purpose calculations and for there direct appointment – drawing 3D motion. Besides, this environment should analyse the behaviour of the system to provide the user with all necessary information about the problem and how to deal with it.
To represent the space charge forces of beam a software based on analytical models for space char... more To represent the space charge forces of beam a software based on analytical models for space charge distributions was developed. Special algorithm for predictor-corrector method for beam map evaluation scheme including the space charge forces were used. This method allows us to evaluate the map along the reference trajectory and to analyze beam envelope dynamics. In three dimensional models the number of computing resources we use is significant. For this purpose graphical processors are used. This software is a part of Virtual Accelerator concept which is considered as a set of services and tools of modeling beam dynamics in accelerators on distributed computing resources.
Analytical and numerical peculiarities of solving nonlinear problems are considered on examples o... more Analytical and numerical peculiarities of solving nonlinear problems are considered on examples of wave equations like KdVB and Kadomtsev-Petviashvili-I equation (KPI). KPI is represented in integro-differential form. Main attention is paid to the problem of asymptotical behavior of solution and appearance of nonphysical artefacts. The numerical solution is carried out by the finite difference method. For a correct representation of the boundary condition along the y axis in numerical simulation a method is proposed for introducing small artificial convection into the original equation in the indicated direction. Along with the introduction of artificial convection, the procedure of trimming of the integral on the bands adjacent to the upper and lower boundaries of the calculated region is used. The results obtained by numerical testing, showed sufficient accuracy and validity of this procedure.
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A. Bogdanov, A. Degtyarev, V. Khramushin
Department of Computer Modelling and Multiprocessor Systems,
Faculty of Applied Mathematics and Control Processes of Saint-Petersburg State University
Architecture of a digital computing system determines the technical foundation of a unified mathematical language for exact arithmetic–logical description of phenomena and laws of continuum mechanics for applications in fluid mechanics and physical field theory. Enhancement of modern computers involvs computing operations in optimally formalized set of locally connected digital geometric objects, existing and transforming independently, and being surrounded by similar virtual entities. Deep parallelization of computing processes serves to the revival of application of functional programming at a new technological level, providing traceability of computing processes with automatic application of multiscale hybrid circuits and adaptive mathematical models for the true reproduction of the fundamental laws of physics and continuum mechanics. Tensor formalization of numerical objects and computing operations serves to spatial interpolation of rheological state parameters and laws of the fluid mechanics as mathematical models in the local coordinates of the elementary numeric cells – large liquid particles.
Keywords: computational experiment, tensor mathematics, fluid mec
Санкт-Петербургский государственный университет (СПбГУ) факультет Прикладной математики-процессов управления кафедра компьютерного моделирования и многопроцессорных систем
Архитектура цифрового вычислительного комплекса определяет техническую основу унифицированного математического языка для строгого арифметико-логического описания явлений и законов механики сплошных сред для прикладных задач гидромеханики и физической теории поля. Совершенствование современных компьютеров стоит на пути вовлечения
вычислительных операций в весьма вольные формализации множества локально-связных цифровых геометрических объектов, независимо существующих и трансформирующихся в окружении аналогичных виртуальных сущностей, и по совокупности моделирующих реальные взаимодействия смежных частиц сплошной среды. Глубокое распараллеливание вычислительных процессов служит возрождению на новом техническом уровне прикладного функционального программирования, обеспечивающего сквозной контроль вычислительных процессов с автоматическим применением разномасштабных гибридных схем и адаптивных математических моделей для достоверного воспроизведения фундаментальных законов физики и механики сплошных сред. Тензорная формализация числовых объектов и вычисли-
тельных операций служит пространственной интерполяции параметров реологического состояния и законов гидромеханики в качестве математических моделей в локальных координатах элементарных числовых ячеек – крупных частиц жидкости.
A. Bogdanov, A. Degtyarev, V. Khramushin
Department of Computer Modelling and Multiprocessor Systems,
Faculty of Applied Mathematics and Control Processes of Saint-Petersburg State University
Architecture of a digital computing system determines the technical foundation of a unified mathematical language for exact arithmetic–logical description of phenomena and laws of continuum mechanics for applications in fluid mechanics and physical field theory. Enhancement of modern computers involvs computing operations in optimally formalized set of locally connected digital geometric objects, existing and transforming independently, and being surrounded by similar virtual entities. Deep parallelization of computing processes serves to the revival of application of functional programming at a new technological level, providing traceability of computing processes with automatic application of multiscale hybrid circuits and adaptive mathematical models for the true reproduction of the fundamental laws of physics and continuum mechanics. Tensor formalization of numerical objects and computing operations serves to spatial interpolation of rheological state parameters and laws of the fluid mechanics as mathematical models in the local coordinates of the elementary numeric cells – large liquid particles.
Keywords: computational experiment, tensor mathematics, fluid mec
Санкт-Петербургский государственный университет (СПбГУ) факультет Прикладной математики-процессов управления кафедра компьютерного моделирования и многопроцессорных систем
Архитектура цифрового вычислительного комплекса определяет техническую основу унифицированного математического языка для строгого арифметико-логического описания явлений и законов механики сплошных сред для прикладных задач гидромеханики и физической теории поля. Совершенствование современных компьютеров стоит на пути вовлечения
вычислительных операций в весьма вольные формализации множества локально-связных цифровых геометрических объектов, независимо существующих и трансформирующихся в окружении аналогичных виртуальных сущностей, и по совокупности моделирующих реальные взаимодействия смежных частиц сплошной среды. Глубокое распараллеливание вычислительных процессов служит возрождению на новом техническом уровне прикладного функционального программирования, обеспечивающего сквозной контроль вычислительных процессов с автоматическим применением разномасштабных гибридных схем и адаптивных математических моделей для достоверного воспроизведения фундаментальных законов физики и механики сплошных сред. Тензорная формализация числовых объектов и вычисли-
тельных операций служит пространственной интерполяции параметров реологического состояния и законов гидромеханики в качестве математических моделей в локальных координатах элементарных числовых ячеек – крупных частиц жидкости.