An efficient simulation algorithm for computing failure probability of a consecutive-k-out-of-r-from-n:F system (linear or circular) with any component reliability, is presented. The algorithm estimates both the failu...
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An efficient simulation algorithm for computing failure probability of a consecutive-k-out-of-r-from-n:F system (linear or circular) with any component reliability, is presented. The algorithm estimates both the failure probability of the system and the associated uncertainty (error). A complete interpretation of the algorithm results is given through a detailed error analysis.
We have developed a simulation algorithm of carrier transport subject to Lorentz force in semiconductor films. The Lorentz current is discretized with the drift and diffusion currents, and the simulation algorithm is ...
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We have developed a simulation algorithm of carrier transport subject to Lorentz force in semiconductor films. The Lorentz current is discretized with the drift and diffusion currents, and the simulation algorithm is implemented in finite difference methods. Hall effect around a grain boundary in a polycrystalline semiconductor film is evaluated as a simulation example, and it is found that a high Hall voltage is generated at the grain boundary. (C) 2011 Elsevier Ltd. All rights reserved.
Piston ring dynamics play important roles on the lubricant characteristic of reciprocating engines which lead to the consequences of engine wear and vast amount of lubricating oil consumption. Due to the complexity of...
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Piston ring dynamics play important roles on the lubricant characteristic of reciprocating engines which lead to the consequences of engine wear and vast amount of lubricating oil consumption. Due to the complexity of motion, a study of motions and effects of the piston ring is mostly conducted in a simulation program. This paper shows a theoretical work and a new simulation algorithm of the 3D piston ring motions. The simulation concept is to determine the positions of the piston ring, which are the solutions of the Newton and Euler equations. Well known models like mixed lubrication model, asperity contact model, and blow-by/blow-back flow model were used in this study. The new simulation algorithm consists of four processes: construction of calculation nodes, use of finite different method, determination of the non-linear equation system, use of parallel computational technique. Two sets of the experimental studies were conducted for simulation verification. First, the gas flows through the static rectangular piston ring pack. Second, the blow-by/blow-back gas flow through the piston ring pack of a single cylinder diesel engine. The good agreement between the experimental and simulation results indicates that the developed simulation program can illustrate the piston ring motions and blow-by/blow-back flow. Since there is no algebraic equation in the ring profile, the presented simulation technique is suitable for the complicated surface of the piston and piston rings. (c) 2007 Elsevier B.V. All rights reserved.
A number of algorithms for computing the simulation preorder on Kripke structures and on labelled transition systems are available. Among them, the algorithm by Rnzato and Tap-paro [2007] has the best time complexity,...
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A number of algorithms for computing the simulation preorder on Kripke structures and on labelled transition systems are available. Among them, the algorithm by Rnzato and Tap-paro [2007] has the best time complexity, while the algorithm by Gentilini et al. [2003] - successively corrected by van Glabbeek and Ploeger [2008] - has the best space complexity. Both space and time complexities are critical issues in a simulation algorithm, in particular memory requirements are crucial in the context of model checking when dealing with large state spaces. Here, we propose a new simulation algorithm that is obtained as a space saving modification of the time efficient algorithm by Ranzato and Tapparo: a symbolic representation of sets is embedded in this algorithm so that any set of states manipulated by the algorithm can be efficiently stored as a set of blocks of a suitable state partition. It turns out that this novel simulation algorithm has a space complexity comparable with Gentilini et al.'s algorithm while improving on Gentilini et al.'s time bound.
In this paper we describe a simple method for inferring the initial states of systems evolving stochastically according to master equations, given knowledge of the final states This is achieved through the use of a re...
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In this paper we describe a simple method for inferring the initial states of systems evolving stochastically according to master equations, given knowledge of the final states This is achieved through the use of a retrodictive stochastic simulation algorithm which complements the usual predictive stochastic simulation approach We demonstrate the utility of this new algorithm by applying it to example problems. including the derivation of likely ancestral states of a gene sequence given a Markovian model of genetic mutation (C) 2010 Elsevier Inc. All rights reserved
Crankshaft is a core part of automobile engine to bear impact load and transmit power. Precision grinding is the most important machining method to achieve high precision of crankshaft main journal. Although many scho...
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Crankshaft is a core part of automobile engine to bear impact load and transmit power. Precision grinding is the most important machining method to achieve high precision of crankshaft main journal. Although many scholars have established various simulation models in the field of cylindrical grinding, it is difficult to carry out effective quantitative simulation for a given crankshaft main journal grinding system. Aiming at the shortcomings of the existing models, a double-rotor dynamic model is proposed, which considers the interaction between the grinding wheel and the main journal, and iterative algorithm is adopted to simulate material removal and roundness change in the grinding process of the main journal. The normal force between grinding wheel and the main journal is defined in detail in the algorithm, which is closer to the actual grinding process. For a given crankshaft grinding system, different grinding strategies of the main journal are quantitatively simulated by using the model. The proposed model and algorithm are validated by experiments, which can provide a basic model for the further study of the crankshaft cylindrical grinding system.
作者:
Zhao, KaihongTaizhou Univ
Sch Elect & Informat Engn Dept Math Taizhou 318000 Zhejiang Peoples R China
In this paper, we study the solvability and generalized Ulam-Hyers (UH) stability of a nonlinear Atangana-Baleanu-Caputo (ABC) fractional coupled system with a Laplacian operator and impulses. First, this system becom...
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In this paper, we study the solvability and generalized Ulam-Hyers (UH) stability of a nonlinear Atangana-Baleanu-Caputo (ABC) fractional coupled system with a Laplacian operator and impulses. First, this system becomes a nonimpulsive system by applying an appropriate transformation. Secondly, the existence and uniqueness of the solution are obtained by an F-contractive operator and a fixed-point theorem on metric space. Simultaneously, the generalized UH-stability is established based on nonlinear analysis methods. Thirdly, a novel numerical simulation algorithm is provided. Finally, an example is used to illustrate the correctness and availability of the main results. Our study is a beneficial exploration of the dynamic properties of viscoelastic turbulence problems.
Multitasking has become surprisingly present in our life. This is mostly due to the fact that nowadays most of our activities involve the interaction with one or more devices. In such a context the brain mechanism of ...
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ISBN:
(纸本)9783030549930;9783030549947
Multitasking has become surprisingly present in our life. This is mostly due to the fact that nowadays most of our activities involve the interaction with one or more devices. In such a context the brain mechanism of selective attention plays a key role in determining the success of a human's interaction with a device. Indeed, it is a resource to be shared among the concurrent tasks to be performed, and the sharing of attention turns out to be a process similar to process scheduling in operating systems. In order to study human multitasking situations in which a user interacts with more than one device at the same time, we proposed in a previous work an algorithm for simulating human selective attention. Our algorithm focuses, in particular, on safety-critical human multitasking, namely situations in which some of the tasks the user is involved in may lead to dangerous consequences if not executed properly. In this paper, we present the validation of such an algorithm against data gathered from an experimental study performed with real users involved concurrently in a "main" task perceived as safety-critical and in a series of "distractor" tasks having different levels of cognitive load.
The focus variation microscopy is widely used and researched in both industrial and academic field. But the 3D construction quality of surface topography is affected by the noise, the double peak value, and the discon...
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ISBN:
(纸本)9781510622579
The focus variation microscopy is widely used and researched in both industrial and academic field. But the 3D construction quality of surface topography is affected by the noise, the double peak value, and the discontinuous surface, and so on. A simulation method for focus variation is proposed based on the physical model of optical imaging and the Point Spread Model(PSF). At first, the linear relationship between the blur factor sigma of Gaussian function and the defocus distance delta is deduced which is called point spread parameter lambda, then, considering the positive correlation between blur factor sigma and blur degree, the difference between the real defocused image and the calculated image by Gaussian convolution operation to real captured focused image is shown. It is used to the objective to computed the accurate value sigma and the spread parameter lambda. At last, the difference between focus measure valued of real image sequence and simulation image sequence is used to verify the method. The simulation method is a judgement basis for focus measurement, the single peak of focus curve, and the identification of high-frequency noise.
The dynamic performance simulation of the beam pumping system is composed of two numerical simulation models. One numerical simulation model is built on the basis of the mathematical model to describe the crank moveme...
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ISBN:
(纸本)9780769549750
The dynamic performance simulation of the beam pumping system is composed of two numerical simulation models. One numerical simulation model is built on the basis of the mathematical model to describe the crank movement, and the other is set up to describe the sucker rod longitudinal vibration. Taking into consideration the continuity conditions of beam pumping system, the comprehensive numerical simulation model for the system is established based on the mentioned above models. The comprehensive simulation algorithm is proposed, which is based on the numerical integration. The simulations reveal that good agreement is found between the experimentally obtained results and the simulations. The results between maximum and minimum polished rod loads of pumping unit appear to be accurate to within plus or minus 11%. In the same calculation environment, the simulation speed of the simulation software applying the comprehensive simulation algorithm is more than 10 times faster than those with the old algorithm. The improvement of the simulation speed establishes the foundation for combinatorial optimization of system dynamic parameters and energy consumption optimization of the system.
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