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Cavitation nozzle is the core component of cavitation generator. It promotes cavitation by its internal special structure, producing bubble and improving the impact force of jet. The structural characteristics directly affect the quality of the cavitation jet. Therefore, the study of internal structure of nozzle is helpful to improve the performance of nozzle. Based on CFD software, taking the Helmholtz...
To develop maritime simulator, mathematical model for ship heave and pitch motions has been established based on conformal mapping method. To verify the validity of the mathematical model, the numerical simulation research is carried out with Wigley model M in regular waves with diiferent Froude number. Comparisons between the simulation results and the experimental data manifest that the proposed...
Atomic Force microscopy (AFM) is a powerful technology for observing and developing the micro/nano world, which has been bringing tremendous revolution opportunities to various fields. An AFM's maneuverability can be enhanced via modification into a nanorobotic system with its scanning probe working as the end-effector. The probe's spatial precision can easily reach to nanometer level, which is commonly...
In 2008, Lotfi Zadeh concluded that to make significant progress toward achievement of human level machine intelligence a paradigm shift is needed. In previous papers we introduced the computational information conservation theory (CICT) approach to get more effective and reliable cognitive, biophysical, and biomedical engineering simulation solutions. CICT new computational information conservation...
Model-based simulation is a sufficient and cost-effective approach for studying and analyzing the maneuverability of ships involving the maneuvers prediction. One important foundation for ensuring its implementation is the determination of the ship dynamic model with relatively low complexity and high accuracy. This study aims at contributing to this research point from two aspects: one is the simplification...
Hyperspectral sensors provides informative data in many fields related to Earth observation. On the coastal zone, the inversion of radiative transfer models of the light has shown the ability to estimate parameters characterizing the water column. Particularly the water column depth, its concentration in non-algal particles, in phytoplankton, the bottom reflectance can be retrieved. Nevertheless the...
The study of high accuracy numerical schemes is a hot topic for decades in the field of compressible turbulence simulations. Linear compact schemes, high-order shock-capturing schemes and the hybrid schemes are three types of schemes used in today's turbulent flow simulations. The fifth-order compact scheme, WENO scheme and hybrid compact-WENO scheme are introduced as the representatives of these...
Turbulence and shock waves interactions occur in a wide range of applications, such as mixing, flow separation and combustion. However, it is still a challenge to accurately simulate these problems. The two demands seem contradictory: the simulation of small turbulence scales requires non-dissipative scheme while the capture of shock requires dissipative scheme. We evaluate the performance of several...
The slip velocity associates the mixture velocity with the phase velocity, establishing vital relationship between the phase and mixture. There are many slip velocity models exist, but the limitation among them is the complexity for real time simulation. A simplified slip velocity model is proposed in this article. Validation of our slip velocity model coupled in the mixture model is conducted with...
In this paper, the dynamics of a flapping wing vehicle are studied. A quasi-steady model is developed to analyze its aerodynamic forces and moments. The unsteady effects are considered both in hovering state and forward flight state. Different from existing flapping wing vehicle dynamics model, the rudder's dynamics are concurrently considered in the proposed one. Numerical simulation is conducted...
This work presents a review of the progress in the development of the numerical methods for sample paths simulation of stochastic differential equations. The error of approximation, the order of the convergence, the stability improvement for Euler methods (explicit, implicit and composite schemes) are studied theoretically as well as numerically. MathLab programs support all the illustrations.
Time-varying problems are widely encountered in various engineering fields, such as signal processing, construction monitoring, and automation. However, traditional arithmetics intrinsically aim at time-invariant problems solving. When running on relatively low-speed processing units, traditional arithmetics may generate quite large and unacceptable lagging errors. In this paper, the problems of discrete...
Recently, based on different error functions, a series of continuous-time Zhang dynamics (CTZD) models have been developed by Zhang et al to solve for time-varying square root. For completeness and also for potential digital hardware implementation, this paper further investigates the discrete-time forms of these CTZD models, which are termed as the discrete-time ZD (DTZD) algorithms. Specifically,...
The paper presents the results of numerical modeling of concrete rheological manifestations under compression, the properties of which are described by a linear model of a viscoelastic material. The computer model of concrete with viscoelastic properties selected for studies identified by experimental research results of concrete samples. Computer simulation was carried out in a software environment...
In current interval-valued linear regression models, meaningless predictions may be generated because the lower bounds of the predicted intervals may be greater than their upper bounds. To avoid this problem, we propose a constrained interval-valued linear regression model based on random set theory. However, due to the introduction of constraints in this model, the expectation of the errors is no...
In an SDN/NFV-enabled network, the behavior of virtual switches is a major concern in determining the overall network performance. The prominent open-source solution for virtual switching is Open vSwitch while the DPDK library has been developed to accelerate the packet processing. In this paper, we develop a general framework for the modeling and the analysis of DPDK-based virtual switches, taking...
We are developing a model of negotiation in a natural language where the communicative goal of the initiator is to achieve the decision of the communication partner about doing a certain action. In order to make a decision, the partner starts a reasoning process, checking the existence of the needed resources as well as the positive and negative aspects of doing the proposed action. If the partner...
We discuss a comprehensive modeling approach for the simulation of quantum dot devices based on the coupling of the van Roosbroeck system with a Markovian quantum master equation. The model equations describe the flow of electrons and holes in semiconductor devices along with a quantum kinetic many-body approach for the quantum dot physics. The consistency of the model equations with respect to non-equilibrium...
Phased-mission system (PMS) can have a number of mission phases with different system configurations of components. In engineering practice, there exist PMSs that have phases with time redundancy, meaning that the system is required to work in operational state for only a given duration of time within such phase, instead of all the phase duration like traditional PMS. For such complex PMS, it is not...
A novel compound image inpainting approach is proposed in this paper. We consider a variational interpolation model based on nonlinear second-order and fourth-order diffusions. A well-posed nonlinear PDE-based model is then derived from the variational scheme. It is then discretized by using an iterative finite-difference based numerical approximation scheme. The proposed reconstruction technique...
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