# Dynamic physical systems

Xem 1-0 trên 0 kết quả Dynamic physical systems
• ### Global existence and long-time behavior of solutions to a class of degenerate parabolic equations

The understanding of the asymptotic behavior of dynamical systems is one of the most important problems of modern mathematical physics. One way to attack the problem for a dissipative dynamical system is to consider its global attractor. This is an invariant set that attracts all the trajectories of the system. In the paper "Global existence and long-time behavior of solutions to a class of degenerate parabolic equations" we study the following semilinear degenerate parabolic equation with variable.

• ### Lecture Operating systems: Lesson 30 - Dr. Syed Mansoor Sarwar

Lecture Operating systems: Lesson 30 - Dr. Syed Mansoor Sarwar. The main topics covered in this lesson include: what is memory management, source code to execution, address binding, logical and physical address spaces, dynamic loading, dynamic linking, and overlays,...

• ### Lecture Windows programming - Lesson 24: Memory management basics

Lecture Windows programming - Lesson 24: Memory management basics. The main topics covered in this chapter include: separate address space for a process, physical and virtual memory, page table, address space: linear and physical address, committed and reserved pages, same address in different processes may map to different things or nothing,...

• ### Lecture Power system stability - Lesson 10: Exciters

Lecture Power system stability - Lesson 10: Exciters provide students with knowledge about dynamic models in the physical structure: exciters; larger scale stability study; functional block diagram; potential types of exciters; block diagram basics; integrator block; first order lag block;...

• ### Lecture Power system stability - Lesson 24: Power System Stabilizers (PSSs)

Lecture Power system stability - Lesson 24: Power System Stabilizers (PSSs) provide students with knowledge about interconnected grids around the world; dynamic models in the physical structure; 2000 bus system results with stabilizers; washout filters and lead-lag compensators; washout parameter variation;...

• ### A simulation study of the amorphous germania structure up to 70 GPa

This work presents the effect of pressure on the local microstructure of amorphous Germania (GeO2). The Molecular Dynamics simulation was performed on systems at 900 K and high pressure up to 70 GPa. The structural properties have been analyzed through the pair correlation function, coordination number distribution, and structure factors.

• ### The effects of physical movement on language learners’ self-confidence and willingness to communicate

In the light of Dynamic Systems Theory, which defines language development as an interaction of various factors in a system, a quantitative research was executed to examine the effects of physical movement in classrooms on students’ self-confidence (SC) and willingness to communicate (WTC) in English.

• ### Mathematical modeling and simulation of a 3 DOFS lower limb rehabilitation robot for post-stroke patient

This paper presents the process of modeling the mathematical model of a 3 degree of freedom (DOF) lower limb rehabilitation, including: kinematic and dynamic model, friction model and motor model. The simulation in MATLAB/Simulink is also carried out to show accuracy and suitability with the physical characteristics of the system model. This result is used to propose control strategies for robot in next studies.

• ### Computational fluid dynamic analysis of physical forces playing a role in brain organoid cultures in two different multiplex platforms

Organoid cultivation in suspension culture requires agitation at low shear stress to allow for nutrient diffusion, which preserves tissue structure. Multiplex systems for organoid cultivation have been proposed, but whether they meet similar shear stress parameters as the regularly used spinner flask and its correlation with the successful generation of brain organoids has not been determined.

• ### Modeling the dynamic mechanisms of HIV infection and the effectiveness of drug treatment

In this work we created a simple dynamic model for HIV infection with three parameters: The concentration of HIV virus, the concentration of health and the infected T-cells. Using a ‘therapy starting moment’ and this dynamic model, we investigated the effectiveness of HIV drug treatment.

• ### Investigation of thermodynamic and mechanical properties of AlyGa1-yAs/GaAs systems by statistical moment method

In this paper, the moment method in statistical dynamics (SMM) is used to study the thermodynamic quantities of AlyGa1-yAs/GaAs systems taking into account the anharmonicity effects of lattice vibrations. The nearest neighbor distance, lattice parameter, isothermal bulk modulus, specific heats at the constant volume and pressure of AlyGa1-yAs/GaAs systems are calculated as functions of the temperature and concentration of Al by using the many-body potential.

• ### A new method against attacks on networked industrial control systems

In this paper, by incorporating knowledge of the physical system under control, we proposed the new method to detect computer attacks that change the behavior of the targeted industrial control system. By using knowledge of the physical system we are able to focus on the final objective of the attack, and not on the particular mechanisms of how vulnerabilities are exploited, and how the attack is hidden. We also analyze the safety of our solution by exploring the effects of stealthy attacks, and by hopping that automatic attack-response mechanisms will not drive the system to an unsafe state.

• ### Investigation of pressure effect on the structure of 3Al2O3.2SiO2 system

This paper studies the structure of the Mullite system (3Al2O3.2SiO2) by Molecular Dynamics simulation (MDs) using the Born–Mayer–Huggins pair interaction and periodic boundary conditions. The simulation was performed with model of 5250 atoms at different pressure and at 3500 K temperature.

• ### Numerical simulation of free and forced oscillations for pendulum type child travel seat

This paper presents a dynamic model of a tilting child travel seat. The child seat is presented as a physical pendulum. Thereby the seat in concert with the child can rotate around a cylindrical joint located above its mass center.

• ### Effect of tillage on nutrient dynamics and physical condition of soil under rainfed rice chick pea based cropping system of bastar, Chhattisgarh

The present study evaluated the effects of long-term tillage operation on soil physical properties and nutrient dynamics on surface soil. The soil samples were collected at 0 to 15cm soil depth profiles in the year of 2016 and 2017 from following treatment (T1) Conventional tillage, (T2) Conventional tillage with seeding by bullock drawn, (T3) Zero till seeding with bullock drawn, (T4) Conservation tillage seeding with country plough and (T5) Utera cropping (T5).

• ### Complex dynamics and control of a novel physical model using nonlocal fractional differential operator with singular kernel

Fractional calculus (FC) is widely used in many interdisciplinary branches of science due to its effectiveness in describing and investigating complicated phenomena. In this work, nonlinear dynamics for a new physical model using nonlocal fractional differential operator with singular kernel is introduced. New Routh-Hurwitz stability conditions are derived for the fractional case as the order lies in [0,2). The new and basic Routh-Hurwitz conditions are applied to the commensurate case. The local stability of the incommensurate orders is also discussed.

• ### Different-lags synchronization in time-delay and circuit simulation of fractional-order chaotic system based on parameter identification

This study constructs a novel four-dimensional fractional-order chaotic system. It verifies chaotic nonlinear dynamic behaviors and physical reliability by numerical simulation and hardware circuit design.

• ### Experimental results of gaslift process

In the paper, the investigation results of periodical gas-lift flows in vertical pipes using experiment method are presented. The experiment facilities consist of flow measurement equipment, gas and fluid supplier facilities, tubing system. To study the influence of medium physical and dynamical characteristics on the process efficiency, two liquid-gas systems are used, namely, water-air and spindle oil-air.

• ### Motion of mechanical systems with non-ideal constraints

In the paper a new method for mechanical systems with non-ideal constraints is presented. It is proved that a mechanical system subjected to physical non-ideal constraints cannot be determined purely by theoretical analysis because the reaction forces depend on the physical parameters of interactive environment, which are identified only by measurement. The principle of compatibility is shown to be an effective tool in combination with experience to investigate such a problem. For illustration the dynamics of a digging machine is investigated.

• ### Constructing electronic phase diagram for the half-filled hubbard model with disorder

The electronic phase diagram of strongly correlated systems with disorder is constructed using the typical-medium theory. For half-filled system, the combination of the linearized dynamical mean field theory and equation of motion approach allows to derive the explicit equations determining the boundary between the correlated metal, Mott insulator, and Anderson insulator phases. Our phase diagram is consistent with those obtained by the more sophisticated methods.