Friction Stir Welding (FSW) is a relatively new solid state joining technique, which is versatile, environment friendly, and energy and time efficient. For a comprehensive understanding of the effects of process condi...
详细信息
Friction Stir Welding (FSW) is a relatively new solid state joining technique, which is versatile, environment friendly, and energy and time efficient. For a comprehensive understanding of the effects of process conditions, such as tool rotation speed and traverse speed, on characterisations of welded materials, it is essential to establish prediction models for different aspects of the materials' behaviours. Because of the high complexity of the FSW process, it is often difficult to derive accurate and yet transparent enough mathematical models. In such a situation, a systematic data-driven fuzzy modelling approach is developed and implemented in this paper to model FSW behaviour relating to AA5083 aluminium alloy, consisting of microstructural features, mechanical properties, as well as overall weld quality. This methodology allows constructing transparent fuzzy models considering both accuracy and interpretability attributes of fuzzy systems. The elicited models proved to be accurate, interpretable and robust and can be further applied to facilitate the optimal design of process parameters, with the aim of finding the optimal combinations of process parameters to achieve desired welding properties.
Abstract We consider inherent robustness properties of model predictive control (MPC) for continuous-time nonlinear systems with input constraints and terminal constraints. We show that when the linear quadratic contr...
详细信息
Abstract We consider inherent robustness properties of model predictive control (MPC) for continuous-time nonlinear systems with input constraints and terminal constraints. We show that when the linear quadratic control law is chosen as the terminal control law, and the related Lyapunov matrix is chosen as the terminal penalty matrix, MPC with nominal prediction model and bounded disturbances has some degree of inherent robustness. We emphasize that the input constraint sets can be any compact set rather than convex sets, and our results do not rely on the continuity of the optimal cost functional or control law in the interior of the feasible region.
Safety analysis is a key activity for the development of railway transportation systems. The analysis is used not only to determine whether new systems do not expose the general public to unduly high levels of risks, ...
详细信息
Abstract In this paper the concept of set invariance for time-delay systems is introduced with a specific attention to the linear discrete-time case. We are interested in the definition of a D(elay) -invariant set wit...
详细信息
Abstract In this paper the concept of set invariance for time-delay systems is introduced with a specific attention to the linear discrete-time case. We are interested in the definition of a D(elay) -invariant set with respect to a bounded polyhedral subset of the state-space. D -invariance conditions are derived based on the Minkowski addition in a first stage, and subsequently translated in feasibility-based tests in order to obtain an efficient computation time
A Sliding Mode (SM) Regulator is proposed for an Antilock Brake System (ABS) control problem by employing Block control SM and regulation concepts. This regulator has robustness against matched and unmatched perturbat...
详细信息
The SCAlable & ReconfigurabLe Electronics plaTforms and Tools project (SCARLETT) was started by European Commission to develop the IMA 2G concept. This paper mentions the main objectives of the SCARLETT project an...
详细信息
The aim of this paper is to design and analyze an observer based on high-order sliding mode to estimate states and unknown inputs in a continuous stirred tank reactor (CSTR). Additionally, the designed HOSM allows to ...
详细信息
This paper describes the different communication patterns followed in industrial communications and maps them into DDS (Data Distribution Service) which is a recent middleware specification. This specification follows...
详细信息
This paper describes the different communication patterns followed in industrial communications and maps them into DDS (Data Distribution Service) which is a recent middleware specification. This specification follows the publisher/subscriber paradigm and it is characterized by providing an API that allows tuning the QoS (Quality of Service) of the applications with a large set of parameters. This paper proposes using DDS as the backbone for industrial communications at the control level. In particular, we advocate its use to combine sending critical information such as alarms and real-time periodic information with less critical information related to configuration, diagnostic or maintenance operations.
Although a few industrial automation systems have also been implemented with DDS, this standard has not yet gained much significance in factory automation applications for several reasons. One of these reasons is that...
详细信息
Although a few industrial automation systems have also been implemented with DDS, this standard has not yet gained much significance in factory automation applications for several reasons. One of these reasons is that since DDS is aimed at a broad range of application domains and it may be necessary to provide certain guidelines in order to use it efficiently in factory automation applications by automation engineers. This paper fills this gap by analyzing the types of traffic found in this kind of applications and describing how to configure the QoS parameters DDS provides. It also presents an ongoing case study that illustrates the application of DDS as communication backbone in factory automation applications.
This paper proposes a new fast 3D image reconstruction algorithm for Diffuse Optical Tomography using reduced order polynomial mappings from the space of optical tissue parameters into the space of flux measurements a...
详细信息
ISBN:
(纸本)9780889868663
This paper proposes a new fast 3D image reconstruction algorithm for Diffuse Optical Tomography using reduced order polynomial mappings from the space of optical tissue parameters into the space of flux measurements at the detector locations. The polynomial mappings are constructed through an iterative estimation process involving structure detection, parameter estimation and cross-validation using data generated by simulating a diffusion approximation of the radiative transfer equation incorporating a priori anatomical and functional information provided by MR scans and prior psychological evidence. Numerical simulation studies demonstrate that reconstructed images are remarkably similar in quality as those obtained using the standard approach, but obtained at a fraction of the time.
暂无评论