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Reaction network design and hybrid modeling of S Zorb

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Chinese Journal of Chemical Engineering 2024年第9期73卷 301-310页

作者： Kai Ji Zhencheng Ye feng qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Qingyuan Innovation Laboratory Quanzhou 362801China

At present,many countries are becoming more and more stringent in terms of sulfur content in fuel oil.S Zorb is a kind of desulfurization technology with advantages of exceptional desulfurization efficiency and small impact on octane *** meet the needs of environmental requirements and the trend of digitalization in the petrochemical industry,a first-principle model of S Zorb was established based on industry *** order to describe the desulfurization and the other side reactions,a reaction network was designed and the kinetic parameters were estimated by the particle swarm optimization *** hybrid models based on the first-principle model and support vector regression method were established to correct the mass fraction of sulfur and predict the research octane number of the refined gasoline *** results indicate that the hybrid models can predict the mass fraction of PIONA,sulfur content and research octane number of the refined gasoline accurately,of which the mean absolute percentage errors are less than 6%.Hybrid models were then applied to optimize the decision variables to minimize the research octane number *** results show that the average reduction of the loss of research octane number is 21.8%,which suggests that the models developed hold promise for guiding practical production.

关键词： Desulfurization Simulation Reaction kinetics Optimization

Improving the off-resonance energy harvesting performance using dynamic magnetic preloading

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Acta Mechanica Sinica 2020年第3期36卷 624-634页

作者： feng qian Shengxi Zhou Lei Zuo Department of Mechanical Engineering Virginia TechBlacksburgVA 24061USA School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

Piezoelectric stack transducers in d33 mode have a much higher mechanical-to-electric energy conversion efficiency compared with d3l mode piezoelectric ***,multilayered piezoelectric stacks usually operate in off-resonance due to the higher stiffness and thereby have a lower power output under low-frequency *** paper proposes to apply the dynamic magnetic pre-loading to a piezoelectric stack transducer to significantly increase the power *** energy harvesting system consists of a multilayered piezoelectric stack with a compliant force amplification frame,a proof mass,and two magnets configured in *** static force-displacement relationship of the magnets is identified from experiments and extended to a dynamic model capable of characterizing the dynamic magnetic *** electromechanical model is developed based on the theoretical derivation and the experimentally identified parameters to predict the voltage outputs under different resistive *** analytical solutions are derived by using the harmonic balance method and show good agreements with the numerical and experimental *** performance of the system is examined and compared with that of the harvester without magnetic *** influences of the distance between the two magnets and the electrical resistive loads on the power output are *** indicate the energy harvesting system with magnetic pre-loading can produce over thousand times more power than the system without magnetic pre-loading at the base excitation of 3 Hz and 0.5 m/s……2,far below the resonance at 243 Hz.

关键词： Energy harvesting Piezoelectric Off-resonance Harmonic balance analysis Magnetic interaction

Solving chemical dynamic optimization problems with ranking-based differential evolution algorithms

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Chinese Journal of Chemical Engineering 2016年第11期24卷 1600-1608页

作者： Xu Chen Wenli Du feng qian Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and Technology Shanghai 200237 China School of Electrical and Information Engineering Jiangsu University Zhenjiang 212013 China

Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-differentiable or explicit mathematical descriptions do not exist. Recently, evolutionary algorithms are gaining popularity for DOPs as they can be used as robust alternatives when the deterministic techniques are invalid. In this article, a technology named ranking-based mutation operator(RMO) is presented to enhance the previous differential evolution(DE) algorithms to solve DOPs using control vector parameterization. In the RMO, better individuals have higher probabilities to produce offspring, which is helpful for the performance enhancement of DE algorithms. Three DE-RMO algorithms are designed by incorporating the RMO. The three DE-RMO algorithms and their three original DE algorithms are applied to solve four constrained DOPs from the literature. Our simulation results indicate that DE-RMO algorithms exhibit better performance than previous non-ranking DE algorithms and other four evolutionary algorithms.

关键词： Dynamic optimization Differential evolution Ranking-based mutation operator Control vector parameterization

Robust tuning method for modified smith predictor

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Journal of Systems Engineering and Electronics 2007年第1期18卷 89-94页

作者： Zhang Guanghui qian feng Shao Huihe Inst. of Automation East China Univ. of Science and Technology Shanghai 200237 P. R. China Inst. of Automation Shanghai Jiaotong Univ. Shanghai 200030 P. R. China

A robust tuning method for ο^Astroem＇s two-degree of Freedom Modified Smith Predictor （MSP） is proposed, and it can achieve the fast setpoint and load disturbance responses independently. The tuning rules may meet the requirements within a certain delay margin according to the robustness theory. The simulation results illustrate that the tuning method is efficient compared with other controllers. Finally, the MSP controller is applied to the 15L batch fermentation system for controlling the temperature in bioreactor, and the experiment results further verify that the robust tuning rules may achieve good performance.

关键词： Tuning Smith Predictor Robusmess Integrating processes Temperature control

Wind field reconstruction for the dispersion modeling of accidental chemical spills on complex geometry

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2712-2724页

作者： Bing Wang feng qian Weimin Zhong Key Laboratory of Advanced Control and Optimization for Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Chemical spills on complex geometry are difficult to model due to the uneven concentration distribution caused by air flow over ground obstacles. Computational fluid dynamics(CFD) is one of the powerful tools to estimate the building-resolving wind flow as well as pollutant dispersion. However, it takes too much time and requires enormous computational power in emergency situations. As a time demanding task, the estimation of the chemical spill consequence for emergency response requires abundant wind field information. In this paper, a comprehensive wind field reconstruction framework is proposed, providing the ability of parameter tuning for best reconstruction accuracy. The core of the framework is a data regression model built on principal component analysis(PCA) and extreme learning machine(ELM). To improve the accuracy, the wind field estimation from the regression model is further revised from local wind observations. The optimal placement of anemometers is provided based on the maximum projection on minimum eigenspace(MPME) algorithm. The fire dynamic simulator(FDS) generates high-resolution data of wind flow over complex geometries for the framework to be implemented. The reconstructed wind field is evaluated against simulation data and an overall reconstruction error of 9% is achieved. When used in real case,the error increases to around 12% since no convergence check is available. With parameter tuning abilities,the proposed framework provides an efficient way of reconstructing the wind flow in congested areas.

关键词： Wind field reconstruction CFD PCA Extreme learning machine Sensor placement

Effect of Magnetic-Impurity Scattering in Disordered Two-Dimensional Square Lattices Around Half Filling

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Communications in Theoretical Physics 2005年第5X期44卷 929-935页

作者： qian feng YANG Yong-Hong Department of Physics Southeast University Nanjing 210096 China National Laboratory of Solid State Microstructures Nanjing University Nanjing 210008 China

Abstract Weak-localization effect in the presence of magnetic impurities is studied in disordered two-dimensional tight-binding square lattices around half filling. Both the magnetic and nonmagnetic impurities are assumed to be randomly distributed on small fractions of the sites, while the nonmagnetic impurities have a strong potential yielding a unitary-limit scattering. We derive in details the expressions of diffusive π modes in the retarded-retarded （or advanced- advanced） channel, which result from the existence of particle-hole symmetry. The quantum interference correction to the density of states is calculated. While the magnetic-impurity scattering suppresses the quantum correction from π-mode cooperon, it does not affect the contribution of π-mode diffuson.

关键词： weak localization magnetic impurity density of states two-dimensional lattice

Analysis of the role of branching angle in the dynamic rupture process on a 3-D branching fault system

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Earth and Planetary Physics 2020年第5期4卷 523-531页

作者： JingXing Fang feng qian HaiMing Zhang School of Earth and Space Sciences Peking UniversityBeijing 100871China

The fault branching phenomenon,which may heavily influence the patterns of rupture propagation in fault systems,is one of the geometric complexities of fault systems that is widely observed in *** this study,we investigate the effect of the branching angle on the rupture inclination and the interaction between branch planes in two-fork branching fault systems by numerical simulation and theoretical analysis based on Mohr’s circle.A friction law dependent on normal stress is used,and special attention is paid to studying how ruptures on the upper and lower branch planes affect the stress and rupture on each other *** results show that the two branch planes affect each other in different patterns and that the intensity of the effect changes with the branching *** rupture of the lower branch plane has a negative effect on the rupture of the upper branch plane in the case of a small branching angle but has almost no negative effect in the case of a large branching *** rupture of the upper branch plane,however,suppresses the rupture of the lower branch plane regardless of whether the branching angle is large or small.

关键词： branching faults Mohr–Coulomb diagram boundary integral equation method earthquake source dynamics rupture selectivity

A Local Quadratic Embedding Learning Algorithm and Applications for Soft Sensing

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Engineering 2022年第11期18卷 186-196页

作者： Yaoyao Bao Yuanming Zhu feng qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Inspired by the tremendous achievements of meta-learning in various fields,this paper proposes the local quadratic embedding learning(LQEL)algorithm for regression problems based on metric learning and neural networks(NNs).First,Mahalanobis metric learning is improved by optimizing the global consistency of the metrics between instances in the input and output ***,we further prove that the improved metric learning problem is equivalent to a convex programming problem by relaxing the *** on the hypothesis of local quadratic interpolation,the algorithm introduces two lightweight NNs;one is used to learn the coefficient matrix in the local quadratic model,and the other is implemented for weight assignment for the prediction results obtained from different local ***,the two sub-mod els are embedded in a unified regression framework,and the parameters are learned by means of a stochastic gradient descent(SGD)*** proposed algorithm can make full use of the information implied in target labels to find more reliable reference ***,it prevents the model degradation caused by sensor drift and unmeasurable variables by modeling variable differences with the LQEL *** results on multiple benchmark datasets and two practical industrial applications show that the proposed method outperforms several popular regression methods.

关键词： Local quadratic embedding Metric learning Regression machine Soft sensor

Effect of chromium content on microstructure and corrosion behavior of W-Cr-C coatings prepared on tungsten substrate

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Frontiers of Materials Science 2015年第1期9卷 77-84页

作者： Yan JIANG Jun-feng YANG qian-feng FANG Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

W-Cr-C coatings with different chromium contents （0-3wt.%） were fabricated on the tungsten substrates by spark plasma sintering （SPS） method from the graphite and chromium mixed powders. SEM and XRD were exploited to analyze the effect of Cr contents on the microstructure of coatings. It was found that the abnormal hollow WC grains disappeared with addition of Cr less than 2%, and the microstructures were largely refined and densified. With further increase of Cr addition, the grains changed slightly but the densificaUon was reduced. The most dense coating was achieved at I wt.% Cr. Corrosion behavior of the W-Cr-C coatings were investigated by impedance spectrum and potentiodynamic polarization tests. Results suggested that the W-1Cr-C coated W sample exhibited the lowest corrosion current density and highest corrosion potential due to the most densified microstructure, indicating that the addition of Cr at 1 wt.% was optimal for WC coating against corrosion.

关键词： W-Cr-C coating spark plasma sintering (SPS) corrosion resistance electrochemical measurement