Surface Traffic Limitations Enhancement (STLE) is a NASA-developed advanced modeling capability for simulating airport surface aircraft movement. STLE augments NASA's Advanced Concept Evaluations System (ACES), wh...
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ISBN:
(纸本)9781424422074
Surface Traffic Limitations Enhancement (STLE) is a NASA-developed advanced modeling capability for simulating airport surface aircraft movement. STLE augments NASA's Advanced Concept Evaluations System (ACES), which is a fast-time computer simulation of nationwide airport and airspace traffic operations. STLE expands ACES software logic and data inputs and outputs to simulate individual aircraft surface trajectories through an airport's terminal gate/ramp, taxiway and runway system. STLE models surface operations using a link-node modeling structure. The modeling simulates aircraft motion dynamics, tracks the movement of each flight, assesses the traffic situation, determines route assignment, detects and resolves potential conflicts, considers node required/planned crossing time constraints, and evaluates traffic throughput and delay. Inputs include specification of link and node graph components, gate and runway configurations, operating rules and procedures, and traffic and airport operating conditions schedules, typically for a 24-hour study period. Output statistics describe transit time and delay by flight and traffic loading as well as queues and transit times by link and node. Node transit control governs actual movement of each aircraft from a link into a node and movement from a node into a link, which determines delay propagation through the surface network. STLE distinguishes sequencing nodes (e.g., taxiway intersections) and complex nodes (e.g., gate, gate group) functions. Link transit control supports this nodal network analysisprocess by managing traffic movement along each link to deliver aircraft to a node. STLE provides a system of working pluggable modules that represent current operations. These pluggable modules are the foundation for subsequent replacement and supplemental models.
Following the increasing complexity of production systems, the increasing relevance of complete life cycle coverage, and increasing consideration of engineering costs engineering processes have to be efficient and sho...
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ISBN:
(纸本)9781467347372;9781467347358
Following the increasing complexity of production systems, the increasing relevance of complete life cycle coverage, and increasing consideration of engineering costs engineering processes have to be efficient and should generate fault free results. Therefore, mechatronical thinking and interoperability along tool chains are potential supporting means. Within this paper the impact of mechatronical thinking on the engineering process for production systems, the provision of interoperability of engineering activities and tools along the engineering process and the resulting structures will for data exchange be considered. Based on the use case of control system engineering a methodology for the creation of a interoperable tool chain exploiting data exchange formats and meta modeling is given.
This paper addresses data-driven mode modeling and Bayesian mode estimation in hidden-mode hybrid systems (HMHS). For experimental validation in a laboratory setting, an HMHS is built upon a six-legged T-hex robot tha...
ISBN:
(纸本)9781467386821
This paper addresses data-driven mode modeling and Bayesian mode estimation in hidden-mode hybrid systems (HMHS). For experimental validation in a laboratory setting, an HMHS is built upon a six-legged T-hex robot that makes use of a library of gaits (i. e., the modes of walking) to perform different motion maneuvers. To accurately predict the behavior of the robot, it is important to first infer the gait being used by the robot. The walking robot's motion behavior can then be modeled as a transition system based on the pattern of switching among these gaits. In this paper, a symbolic time-series-based statistical learning method has been adopted to construct the generative models of the gaits. Efficacy of the proposed algorithm is demonstrated by laboratory experimentation to model and then infer the hidden dynamics of different gaits for the T-hex walking robot.
For the multi-packet transmission networked control systems with uncertain short time delay and data dropouts, system modeling and control problem is studied on the condition that packet transmission using dynamic sch...
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ISBN:
(纸本)9780769535166
For the multi-packet transmission networked control systems with uncertain short time delay and data dropouts, system modeling and control problem is studied on the condition that packet transmission using dynamic scheduling strategy. Supposing that the packet transmission process has the markov characteristic, it is modeled as a class of discrete markov jumping system with parameter uncertainty. The sufficient condition for the mean square asymptotic stability of the system is derived based on the linear matrix inequality (LMI) approach, a state feedback controller design method is also provided Simulation result shows the validity of the method
In recent years, soft sensors have been established as a valuable alternative to the traditional hardware sensors for the acquisition of critical information regarding "difficult-to-measure" process variable...
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ISBN:
(纸本)9781467379939
In recent years, soft sensors have been established as a valuable alternative to the traditional hardware sensors for the acquisition of critical information regarding "difficult-to-measure" process variables and/or parameters in chemical process monitoring and control. Soft sensors can also be modified as a novel process identification tool for process monitoring and model based control. Often, in polymer industries the main polymerization reaction is highly nonlinear and complex to model accurately by the conventional "first principles" approach. In such cases, genetic programming (GP)-a novel artificial intelligence-based exclusively data driven modeling technique-can be employed for process identification. In this work GP-based soft sensors have been developed for a continuous styrene polymerization reactor. The resulting GP-based models (soft sensor) showed high prediction and generalization performances. The best performing model was successfully utilized in designing a model predictive control (MPC) scheme for the polymerization reactor.
By analyzing the impact of cyber attack on the cyber physical power system (CPPS), a Bayesian based on petri net(BBPN) quantitative risk assessment method was proposed in this paper. Petri net as an important formal t...
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ISBN:
(纸本)9781538660058
By analyzing the impact of cyber attack on the cyber physical power system (CPPS), a Bayesian based on petri net(BBPN) quantitative risk assessment method was proposed in this paper. Petri net as an important formal tool for modeling, analysis and analysis of distributed, parallel and real-time systems provides a solid foundation for CPS modeling. However, Petri nets lack the ability to describe spatial information, so it is impossible to fully model CPS. Incorrect system modeling can directly affect system reliability and even life-threatening and property safety, Therefore, when modeling and analyzing CPS characteristics, a more complete modeling method is needed. This paper extends the Defect extension time Petri net and constructs a spatiotemporal Petri net that can describe the positional changes of CPS physical entities. This paper also analyzes the physical characteristics of CPS in detail, starting from the classification and characteristics of physical entities, and deeply studying the properties of CPS physical entities and their location transition process. Proposing a formal modeling method for CPS physical entities;Introducing spatial factors on the basis of Petri nets by analyzing the characteristics that Petri nets must satisfy, getting the formal definition of Petri net, It can not only describe the physical entity logic and time-level behavior, hut also describe the state changes caused by physical entity location changes. Firstly, using petri net to finely model important equipment in information systems, and then based on these models and the attack source delivery path, establishing the fine Bayesian cyber attack model. With the combination of the observed real-time attack events, we dynamically update the probability of attack behavior based on Bayesian reasoning. Finally, we proposed the optimal load control algorithm considering the node failure, comprehensive quantitative assessing the impact of cyber attacks on the CPPS.
The analysis of the behavior of simulation models and the subsequent communication of their results are critical but often neglected activities in simulation modeling. To overcome this issue. this paper proposes an in...
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ISBN:
(纸本)9781467397438
The analysis of the behavior of simulation models and the subsequent communication of their results are critical but often neglected activities in simulation modeling. To overcome this issue. this paper proposes an integrated metamodeling approach based on structural equation modeling using the partial least squares algorithm. The suggested method integrates both a priori information from the conceptual model and the simulation data output. Based on this. we estimate and evaluate the core relationships and their predictive capabilities. The resulting structural equation metamodel exposes structures in the behavior of simulation models and allows for their better communication. The link to theory via the conceptual model considerably increases understanding compared with other meta modeling approaches.
3D Visualisation is a powerful tool for dynamic analysis of multibody systems such as robots. The basic idea of the paper is to develop the models of multibody systems from two points of view: the dynamic and geometri...
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ISBN:
(纸本)9788897999546
3D Visualisation is a powerful tool for dynamic analysis of multibody systems such as robots. The basic idea of the paper is to develop the models of multibody systems from two points of view: the dynamic and geometric. The dynamic model is based on bond graph technique and is developed using a suitable bond graphs modelling and simulation environment (BondSim). To develop 3D model in a virtual scene another program the BondSimVisual is used. It is based on VTK visualization pipeline technology. These two models interact by two-way inter process communication (IPC) based on the named pipes. Thus, two models appear as a single complex model running on the same or separate computers connected by a LAN. The attention of this paper is focused on development of visual 3D models of the multibody systems. The proposed approach is illustrated on example of a pendulum and industrial robot ABB IRB 1600.
Structural equation modelling (SEM) is a multivariate method that incorporates ideas from regression, path-analysis and factor analysis. A Bayesian approach to SEM may enable models that reflect hypotheses based on co...
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Structural equation modelling (SEM) is a multivariate method that incorporates ideas from regression, path-analysis and factor analysis. A Bayesian approach to SEM may enable models that reflect hypotheses based on complex theory. The development and application of Bayesian approaches to SEM has, however, been relatively slow but with modern technology and the Gibbs sampler, is now possible. The Gibbs sampler can be used to obtain samples of arbitrary size from the posterior distribution over the parameters of a structural equation model (SEM) given covariance data and a prior distribution over the parameters. Point estimates, standard deviations and interval estimates for the parameters can be computed from these samples. This study shows that the conditional distributions required in the Gibbs sampler are familiar distributions, hence the algorithm is very efficient. A goodness of fit statistic for assessing the proposed model is presented. An illustrative example with a real data is presented.
Based on the knowledge rule models and the analysis mathematical models, the two-level real-time expert control system (ECS) was established. With the self-learning ability in expert optimal mode, the expert system (E...
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