The shortest transportation route is an important and basic problem in the military transportation. Currently, there are several methods developed to solve this problem, for example, the replace algorithm, Dijkstra al...
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ISBN:
(纸本)9781424442461
The shortest transportation route is an important and basic problem in the military transportation. Currently, there are several methods developed to solve this problem, for example, the replace algorithm, Dijkstra algorithm, linear programming algorithm, etc.. This paper proposes a new method to the shortest route problem - simulation algorithm of Petri network. This method defines the operation rule and step of the simulation device of Petri net on the basis of general Petri network. It changes the undirectional transportation network into EPN model automatically with the simulation device of Petri net, while describes the elements of the network. Meanwhile, 'Place time' is used to replace the arc length to perform the simulation operation and numerical processing of the simulation target system of the network. It calculates the corresponding shortest route and length automatically. This method is more vivid, more intuitionistic and faster than the existing methods, it is a more practical method and means.
This paper presents a simulation algorithm to analyze a type of colored time Petri nets, in which a time interval is associated with each transition. Specifically, we first unfold colored time Petri nets to standard t...
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ISBN:
(纸本)9781479913343
This paper presents a simulation algorithm to analyze a type of colored time Petri nets, in which a time interval is associated with each transition. Specifically, we first unfold colored time Petri nets to standard time Petri nets and then develop a simulation algorithm of time Petri nets to realize the simulation of colored time Petri nets. A model of a real system is used to demonstrate and validate our approach.
We show how bisimulation equivalence and simulation preorder on probabilistic LTSs (PLTSs), namely the main behavioural relations on probabilistic nondeterministic processes, can be characterized by abstract interpret...
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We show how bisimulation equivalence and simulation preorder on probabilistic LTSs (PLTSs), namely the main behavioural relations on probabilistic nondeterministic processes, can be characterized by abstract interpretation. Both bisimulation and simulation can be obtained as completions of partitions and preorders, viewed as abstract domains, w.r.t. a pair of concrete functions that encode a PLTS. This approach provides a general framework for designing algorithms that compute bisimulation and simulation on PLTSs. Notably, (i) we show that the standard bisimulation algorithm by Baier et al. (2000) can be viewed as an instance of such a framework and (ii) we design a new efficient simulation algorithm that improves the state of the art.
Accelerated stormwater runoff creates environmental problems in many urban communities. Methods for reducing this runoff are available, but most do not work well if soils are poorly drained. Analysis of a rain barrel ...
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Accelerated stormwater runoff creates environmental problems in many urban communities. Methods for reducing this runoff are available, but most do not work well if soils are poorly drained. Analysis of a rain barrel implementation strategy that diverts only roof runoff, for which there is a beneficial garden use, is presented and illustrated with a case study application. This approach reduces operation to the growing season and requires that the rain barrel function to benefit the garden and to reduce runoff, but may improve homeowner acceptance and operation. General methods for quantifying and bounding system effectiveness are illustrated. Case study results indicate that a 50-gal. (189-L) rain barrel connected to 25% of a 2,000-ft(2) (186-m(2)) residential roof and serving a 150-ft(2) (14-m(2)) garden in Cleveland Heights, Ohio, would reduce the total roof growing-season runoff by 2.4-5.4% and the total annual roof runoff by 1.4-3.1%, depending on the irrigation strategy applied. Increasing garden and barrel size could increase the annual runoff reduction to 7.4%, but barrel capacity constrains additional reductions. These results illustrate the stormwater management limitations of rain barrels used in the case study location. The degree to which the analytical methods and results may be generalized to other communities is discussed. DOI: 10.1061/(ASCE)EE.1943-7870.0000663. (C) 2013 American Society of Civil Engineers.
As Dempster-Shafer theory spreads in different application fields, and as mass functions are involved in more and more complex systems, the need for algorithms randomly generating mass functions arises. Such algorithm...
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As Dempster-Shafer theory spreads in different application fields, and as mass functions are involved in more and more complex systems, the need for algorithms randomly generating mass functions arises. Such algorithms can be used, for instance, to evaluate some statistical properties or to simulate the uncertainty in some systems (e.g., data base content, training sets). As such random generation is often perceived as secondary, most of the proposed algorithms use straightforward procedures whose sample statistical properties can be difficult to characterize. Thus, although such algorithms produce randomly generated mass functions, they do not always produce what could be expected from them (for example, uniform sampling in the set of all possible mass functions). In this paper, we briefly review some well-known algorithms, explaining why their statistical properties are hard to characterize. We then provide relatively simple algorithms and procedures to perform efficient random generation of mass functions whose sampling properties are controlled.
The shortest transportation route is an important and basic problem in the military ***, there are several methods developed to solve this problem,for example,the replace algorithm,Dijkstra algorithm,linear programmin...
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The shortest transportation route is an important and basic problem in the military ***, there are several methods developed to solve this problem,for example,the replace algorithm,Dijkstra algorithm,linear programming algorithm,etc..This paper proposes a new method to the shortest route problem–simulation algorithm of Petri *** method defines the operation rule and step of the simulation device of Petri net on the basis of general Petri *** changes the undirectional transportation network into EPN model automatically with the simulation device of Petri net,while describes the elements of the network. Meanwhile,‘place time’is used to replace the arc length to perform the simulation operation and numerical processing of the simulation target system of the *** calculates the corresponding shortest route and length *** method is more vivid,more intuitionistic and faster than the existing methods,it is a more practical method and means.
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.
Shot-peening is the process of repeatedly hitting the work piece surface with small balls, making overlapping indentations on the surface. This process is extensively used on shafts, gears, springs, and jet engine par...
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ISBN:
(纸本)9783037854280
Shot-peening is the process of repeatedly hitting the work piece surface with small balls, making overlapping indentations on the surface. This process is extensively used on shafts, gears, springs, and jet engine parts because it imparts compressive residual stresses on the surface, thus improving the fatigue life of components. Under-peening does not give a sufficient fatigue life while over-peening induces cracking and reduces fatigue performance. Hence, determining optimal peening conditions such as peening time is very important. In general, optimal peening conditions are experimentally determined by measuring arc-height using Almen-strip or calculating coverage using microscope images. Shot-peening coverage is defined as the proportion of the exposed surface that has been impacted in a given time of shot-peening. To save the time and effort spent in repeating experimental measurement needed whenever the geometry of a work piece and peening conditions change, this paper presents a computer simulation algorithm for the prediction of shot-peening coverage, which is based on the geometry of a work piece. An example is presented to validate the proposed method.
This work is to study the dynamic characteristics of an oil turbine (OT) in the lubricating system of large-scale steam turbines. The configuration and the functions of OT are introduced. The mathematical models are a...
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This work is to study the dynamic characteristics of an oil turbine (OT) in the lubricating system of large-scale steam turbines. The configuration and the functions of OT are introduced. The mathematical models are accordingly explored. In addition, the experiment results are predicted and compared with the theoretical prediction. Finally, the dynamic characteristics in the start-up procedure are simulated and analyzed. The agreement between the numerical results and the experiment observations is in general satisfactory. It shows that the numerical simulation approach is reliable, and could be applied into the dynamic characteristics research and optimization of other complicated fluid systems as hydropower station. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Society for Resources, Environment and Engineering
This work is to study the dynamic characteristics of an oil turbine (OT) in the lubricating system of large-scale steam turbines. The configuration and the functions of OT are introduced. The mathematical models are a...
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This work is to study the dynamic characteristics of an oil turbine (OT) in the lubricating system of large-scale steam turbines. The configuration and the functions of OT are introduced. The mathematical models are accordingly explored. In addition, the experiment results are predicted and compared with the theoretical prediction. Finally, the dynamic characteristics in the start-up procedure are simulated and analyzed. The agreement between the numerical results and the experiment observations is in general satisfactory. It shows that the numerical simulation approach is reliable, and could be applied into the dynamic characteristics research and optimization of other complicated fluid systems as hydropower station.
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