Deep learning (DL) methods have brought world-shattering breakthroughs, especially in computer vision and classification problems. Yet, the design and deployment of DL methods in time series prediction and nonlinear system identification applications still need more progress. In this paper, we present DL frameworks that are developed to provide novel approaches as solutions to the aforementioned engineering problems. The proposed DL frameworks leverage the advantages of autoencoders and long-short term memory network, which are known being data compression and recurrent structures, respectively, to design Deep Neural Networks (DNN) for modeling time series and nonlinear systems with high performance. We provide recommendations on how deep AEs and LSTMs should be utilized to end up with efficient Prediction-focused (Pf) and Simulation-focused (Sf) DNNs for time series and system identification problems. We present systematic learning methods for the DL frameworks that allow straightforward learning of Pf-DNN and Sf-DNN models in detail. To demonstrate the efficiency of the developed DNNs, we present various comparative results conducted on the benchmark and real-world datasets in comparison with their conventional, shallow, and deep neural network counterparts. The results clearly show that the deployment of the proposed DL frameworks results with DNNs that have high accuracy, even with a low dimensional feature vector.
In the recent years it has been demonstrated that type-2 fuzzy logic systems are more effective in modeling and control of complex nonlinear systems compared to type-1 fuzzy logic systems. An inverse controller based on type-2 fuzzy model can be proposed since inverse model controllers provide an efficient way to control nonlinear processes. Even though various fuzzy inversion methods have been devised for type-1 fuzzy logic systems up to now, there does not exist any method for type-2 fuzzy logic systems. In this study, a systematic method has been proposed to form the inverse of the interval type-2 Takagi-Sugeno fuzzy model based on a pure analytical method. The calculation of inverse model is done based on simple manipulations of the antecedent and consequence parts of the fuzzy model. Moreover, the type-2 fuzzy model and its inverse as the primary controller are embedded into a nonlinear internal model control structure to provide an effective and robust control performance. Finally, the proposed control scheme has been implemented on an experimental pH neutralization process where the beneficial sides are shown clearly. 相似文献
Selecting the best transportation investment project (TIP) is often a difficult task, since many social, environmental and economic criteria have to be considered simultaneously. Evaluating a set of different projects, especially the best set of alternatives, portfolios, is even more complex. Pursuing the goal of selecting the best TIP portfolio, we propose a fuzzy assessment method to aid the selection process of a multi-criterion project by utilizing the concept of entropy and interval normalization procedure in a fuzzy analytic hierarchy process (F-AHP). Then, regarding this informative phase, we propose a fuzzy linear programming model to select the best TIP portfolio under uncertain cost pressure. A real case study is conducted to illustrate the efficiency of the proposed method. 相似文献
We design and investigate the performance of fuzzy logic-controlled (FLC) active suspensions on a nonlinear vehicle model
with four degrees of freedom, without causing any degeneration in suspension working limits. Force actuators were mounted
parallel to the suspensions. In this new approach, linear combinations of the vertical velocities of the suspension ends and
accelerations of the points of connection of the suspension to the body have been used as input variables. The study clearly
demonstrates the effectiveness of the fuzzy logic controller for active suspension systems. Suspension working space degeneration
is the most important problem in various applications. Decreasing the amplitudes of vehicle body vibrations improves ride
comfort. Body bounce and pitch motion of the vehicle are presented both in time domain when travelling over a ramp-step road
profile and in frequency domain. The results are compared with those of uncontrolled systems. At the end of this study, the
performance and the advantage of the suggested approach and the improvement in ride comfort are discussed. 相似文献
Material research on perovskite‐type oxides (ABO3) has been driven by the recognition of their unique properties primarily attributed to the presence of oxygen octahedron (BO6). Since 2003, the discovery of strong coupling in TbMnO3 and BiFeO3 has stimulated new interests in understanding the relationship between magnetic and electric properties in perovskites. In this article, we report our recent work on the magnetic superexchange interaction and charge formation in copper‐doped LaFeO3 using high‐temperature neutron diffraction and thermoelectric measurements. In situ neutron diffraction measurements show a loss of antiferromagnetic ordering above 450°C. With an increase in Cu content, the (Fe, Cu)‐O bond length decreases and the (Fe, Cu)–O–(Fe, Cu) bond angle increases, which leads to an enhancement of the Fe–O–Fe superexchange interaction. Thermoelectric and electrical measurements show that the formation of electron holes in Cu‐doped LaFeO3 is a thermally activated process with two distinct regions with a transition temperature near 450°C, in congruence with the magnetic measurements. Our work show that Cu is in 3+ state in La(Fe,Cu)O3 at room temperature, resulting in the maximum superexchange interaction between Fe3+ ions. 相似文献