Studies had reported that the performance of multi-objective gaze-independent BCIs under covert attention conditions was lower than the matrix speller BCIs under overt attention conditions. However, no research has co...
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ISBN:
(纸本)9781509012572
Studies had reported that the performance of multi-objective gaze-independent BCIs under covert attention conditions was lower than the matrix speller BCIs under overt attention conditions. However, no research has compared the performance of multi-objective gaze-independent BCIs under covert attention conditions with under overt attention conditions,when visual angle doesn't exceed 1o. For exploration of the above problem, two paradigms developed from Geometric Speller(Geo Spell) have been built. Ten healthy participants had participated in this study. Results show that the performance of the gaze-independent BCI is substantially higher when the participant could gaze directly at targets. However, the multi-objective gaze-independent BCIs under covert attention conditions are competitive in terms of evoking N200(p<0.05).
Probabilistic model has already been widely used for process monitoring. However, the obtained factors may contain quality-unrelated information, which is harmful to the quality-related process monitoring. Meanwhile, ...
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Probabilistic model has already been widely used for process monitoring. However, the obtained factors may contain quality-unrelated information, which is harmful to the quality-related process monitoring. Meanwhile, considering the situation of unequal sample rates of process and quality variables, a semi-supervised orthogonal factor analysis(Semi-SOFA) model is presented, further, to improve robustness, Semi-SOFA is extended to weighted form(WSemi-SOFA). This paper performs orthogonal decomposition on the obtained factors, which divides them into two parts: quality-related one and quality-unrelated one. Based on it, the corresponding T statistics are designed to offer quality-related process monitoring, respectively. Besides, SPE statistics are constructed as supplement to monitor residuals. For effectiveness demonstration of the proposed method, TE benchmark is utilized.
In recent years, most works on deception attacks(like [1])have been considered the dynamic detection attack, by designing appropriate algorithms capable of sensing the existence of attacks. However, there still does n...
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In recent years, most works on deception attacks(like [1])have been considered the dynamic detection attack, by designing appropriate algorithms capable of sensing the existence of attacks. However, there still does not exist a unified framework for the event-based resilient formation tracking issue under deceptions attacks. In most related works on formation control of multi-agent systems(MASs), for example in [2] and [3], neither the directed information flow nor the attacks are considered. Therefore, this study mainly considers how to realize the stabilization and desired performance under the unknown deception attacks by presenting some explicit properties including their frequency, duration and magnitude. This paper designs the resilient edge-triggering strategies under deception attacks, i.e., the formation tracking control of MASs can be realized and preserved even if the communication links undergo deception attacks. In the near future, the work can be extended into several cases:(1)The stochastic case corresponding to certain distribution [4];(2) The attitude control issue of the aircraft systems under deceptions attacks;(3) The formation issues of mobile robots with time-varying topologies.
Batch process data are essentially *** existing methods on batch process monitoring such as multiway partial least squares(MPLS)and multiway principal component analysis(MPCA)are based on unfolding procedure which rep...
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Batch process data are essentially *** existing methods on batch process monitoring such as multiway partial least squares(MPLS)and multiway principal component analysis(MPCA)are based on unfolding procedure which represents three-way batch data as a vector in high-dimensional *** a result of destroying data structures,these methods may lead to information *** this article,batch data are considered as a third order tensor and HOPLS is introduced to deal with the data directly instead of performing unfolding procedure.A HOPLS-based online monitoring approach is developed and two new statistics:HO-SPE and HO-T2are constructed for fault detection and *** effectiveness of this approach is illustrated by a benchmark fed-batch penicillin fermentation *** comparison of monitoring results shows that the proposed approach is superior to MPLS,and it can achieve accurate detection of various types of process faults occurring in the batch operation.
Gasoline blending is a critical process in petroleum refineries. Real-time optimization(RTO) techniques have been popular with the applications for the blending process for optimization purpose. However the dependency...
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Gasoline blending is a critical process in petroleum refineries. Real-time optimization(RTO) techniques have been popular with the applications for the blending process for optimization purpose. However the dependency of RTO on the measurement of the component impairs its applicability. Therefore how to utilize the blending model and the product measurement to free RTO from the component measurement is the major research topic in this paper. Unscented Kalman Filter, due to its ability to estimate the parameter for nonlinear model, is chosen to estimate component properties based on the product measurement. The RTO strategy is then proposed with the UKF method for the recipe calculation periodically. Furthermore, the proposed RTO is tested with the gasoline blending benchmark problem, while the results are compared with the ideal blending case. The accuracy of the component estimation and the efficiency of the RTO are verified with the results.
the Molecular weight distribution(MWD)is an important quality index for the polymer material,but detecting the MWD in real-time is still difficult by *** rapid real-time detection method for MWD with good accuracy is ...
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the Molecular weight distribution(MWD)is an important quality index for the polymer material,but detecting the MWD in real-time is still difficult by *** rapid real-time detection method for MWD with good accuracy is the current hotspot in the polymer *** from the method other literatures have described,in this work the reaction mechanism and the industrial information will be merged to build a hybrid model for the MWD to solve the prediction accuracy and real-time problems,using the weighted superposition of the distribution function on each active center of catalyst to fit the MWD and applying the multi-output support vector machine regression(MSVR)algorithm to describe the relationship between process conditions and the parameters of distribution *** the unconstrained nonlinear optimization method has been used to optimize the process conditions based on the hybrid ***,the application of the above-mentioned approach in the ethylene polymerization process has verified the feasibility.
In recent years,the technology accelerates the fierce competition of *** the information explosion,the research on process scheduling gets more *** paper summarizes the previous studies about unrelated parallel machin...
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In recent years,the technology accelerates the fierce competition of *** the information explosion,the research on process scheduling gets more *** paper summarizes the previous studies about unrelated parallel machine scheduling problem,then gives a detailed mathematical description for the unrelated parallel machine scheduling *** with the development of intelligent optimization algorithms,it puts forward an improved estimation of distribution algorithms IEDANS to solve the unrelated parallel machine scheduling *** ideas about VNS also integrated into the *** the advantages and disadvantages of intelligent algorithms,the actual application process presents a new encoding for the *** using the processing time matrix,the algorithm can get more knowledge of the *** simulation results show that the IEDANS algorithm can solve the problem *** can converge to the global optimization without costing much time.
chemicalprocesses with multiple operational modes are common in modern process *** fault diagnosis methods meet challenges when facing multimodal complex data *** order to tackle this challenge,a new fault diagnosis ...
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chemicalprocesses with multiple operational modes are common in modern process *** fault diagnosis methods meet challenges when facing multimodal complex data *** order to tackle this challenge,a new fault diagnosis approach utilizing hidden Markov model(HMM) is developed in this paper.A HMM trained by normal process data with multimodal feature has several hidden *** operating mode is represented by a hidden state which should be described via a finite Gaussian mixture *** multivariate Gaussian mixture distribution targets complex data distribution within each individual ***,for a monitored sample,the Mahalanobis distance(MD) inside each Gaussian component is constructed as monitoring *** contribution index is obtained through the differential decomposition along every variable direction to MD-based monitoring *** last,the hidden state Gaussian component probability strategy is used to integrate local monitoring index and local variable contribution index across all Gaussian components into a global monitoring indicator and a global variable contribution *** derived variable contribution index with probabilistic feature is employed to locate faulty *** to a numerical simulation and the Tennessee Eastman(TE) process display the fault detection and diagnosis performance of our proposed method.
For probabilistic monitoring of multimode processes,this paper introduced a monitoring scheme that integrates joint probability density and weighted probabilistic principal component analysis based on coefficient of v...
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For probabilistic monitoring of multimode processes,this paper introduced a monitoring scheme that integrates joint probability density and weighted probabilistic principal component analysis based on coefficient of variation(CV-WPPCA). A joint probability based on 2 statistic was constructed for mode identification. After it concentrated maximum fault-relevant information into dominant subspace by identifying and extracting important noise factors from the residual subspace,the new approach utilized a weighting strategy based on coefficient of variation method to highlight the useful information in the reconstructed dominant subspace. A case study on the Tennessee Eastman process was applied to demonstrate the efficiency of the proposed method.
The model of an Orbal oxidation ditch activated sludge process was set up based on ASM3 and Takacs' s double index settlement rate of secondary sedimentation tank model in this paper. According to the condition of...
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The model of an Orbal oxidation ditch activated sludge process was set up based on ASM3 and Takacs' s double index settlement rate of secondary sedimentation tank model in this paper. According to the condition of the multi-objective output simulation model, multi-objective particle swarm optimization algorithm(MOPSO) is used to calibrate part of the high sensitivity parameters in the activated sludge process model. Simulation results show that the effectiveness of MOPSO for parameter calibration is obvious, which can further improve the accuracy of the model.
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