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A Wavelet Neural Network Based Non-linear Model Predictive Controller for a Multi-variable Coupled Tank System

International Journal of Automation and computing 2015年第2期12卷 156-170页

作者： Kayode Owa Sanjay Sharma Robert Sutton School of Marine Science and Engineering University of Plymouth Marine and Industrial Dynamic analysis (MIDAS) Research group University of Plymouth

In this paper, a novel real time non-linear model predictive controller(NMPC) for a multi-variable coupled tank system(CTS) is designed. CTSs are highly non-linear and can be found in many industrial process applications. The involvement of multi-input multi-output(MIMO) system makes the design of an effective controller a challenging task. MIMO systems have inherent couplings,interactions in-between the process input-output variables and generally have an complex internal structure. The aim of this paper is to design, simulate, and implement a novel real time constrained NMPC for a multi-variable CTS with the aid of intelligent system techniques. There are two major formidable challenges hindering the success of the implementation of a NMPC strategy in the MIMO case. The first is the difficulty of obtaining a good non-linear model by training a non-convex complex network to avoid being trapped in a local minimum solution. The second is the online real time optimisation(RTO) of the manipulated variable at every sampling time.A novel wavelet neural network(WNN) with high predicting precision and time-frequency localisation characteristic was selected for an MIMO model and a fast stochastic wavelet gradient algorithm was used for initial training of the network. Furthermore, a genetic algorithm was used to obtain the optimised parameters of the WNN as well as the RTO during the NMPC strategy. The proposed strategy performed well in both simulation and real time on an MIMO CTS. The results indicated that WNN provided better trajectory regulation with less mean-squared-error and average control energy compared to an artificial neural network. It is also shown that the WNN is more robust during abnormal operating conditions.

关键词： Wavelet neural network(WNN) non-linear model predictive control(NMPC) real time practical implementation multi-input multi-outpu

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Note on characteristics of homogeneous-heterogeneous reaction in flow of Jeffrey fluid

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Applied Mathematics and Mechanics(English Edition) 2015年第10期36卷 1319-1328页

作者： M.FAROOQ A.ALSAEDI T.HAYAT Department of Mathematics Quaid-i-Azam University Nonlinear analysis and Applied Mathematics (NAAM) Research group Faculty of Science King Abdulaziz University

This letter describes the characteristics of homogeneous-heterogeneous re- action in the boundary layer flow of a Jeffrey fluid due to an impermeable horizontal stretching sheet. An analysis is carried out through the similar values of reactant and auto catalyst diffusion coefficients. Heat released by the reaction is not accounted. The exact solution for the flow of the Jeffrey fluid is constructed. The series solution for the concentration equation is derived. The velocity and concentration fields reflecting the impact of interesting parameters are plotted and examined.

关键词： Jeffrey fluid stretching sheet homogeneous-heterogeneous reaction

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Sediment generation and soil mound denudation in areas of high-density tree throw along a river valley in the Jura Mountains, Switzerland

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Journal of Mountain Science 2021年第2期18卷 377-391页

作者： Philip GREENWOOD Jan BAUER Nikolaus J KUHN Physical Geography&environmental Change Research group Department of Environmental SciencesUniversity of BaselKlingelbergstrasse 27Basel-4056Switzerland

A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest *** aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring *** the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 *** tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(***,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(<2 mm diameter),or the equivalent of 3.8×10^(-4) m^(3) m^(-2).The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December *** the 18-year period since both storms,this represents an annual sediment transport rate of 2.7×10^(-5) m^(3) m^(-1) yr^(-1).Exploring the relationship with wind on fall direction,65.5%of tree throws(143)generally fell in a downslope direction irrespective of hillslope aspect on which they were *** infers that individual storms may not have been responsible for the majority of tree throws,but instead,could be associated with root *** the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once tr

关键词： Tree throw Hillslope processes Sediment generation mechanism Sediment transport rate Soil mound Ibach river valley

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Simulation of dilatancy-controlled gas migration processes in saturated bentonite using a coupled multiphase flow and elastoplastic H2 M model

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 803-813页

作者： Eike Radeisen Hua Shao Jürgen Hesser Olaf Kolditz Wenjie Xu Wenqing Wang Department of Rock Characterization for Storage and Final Disposal Federal Institute for Geosciences and Natural Resources(BGR)Hannover30655Germany Department of environmental Informatics Helmholtz Center for Environmental Research(UFZ)Leipzig04341Germany Department of Applied environmental systems analysis Technische Universität DresdenDresden01069Germany Department of Civil Engineering and Architecture Zhejiang UniversityHangzhou310058China

Dilatancy-controlled gas flow in preferential pathways plays a key role in the safety analysis of radioactive waste *** is particularly the case for bentonite,an often-preferred barrier *** flow in preferential pathways is characterized by localization and spontaneous behavior,which is challenging to simulate in numerical models due to strong hydro-mechanical *** analyze a laboratory experiment in the framework of the DECOVALEX-2023 project,this study introduced a new approach of combining continuous modelling methods with spatial material properties derived from material heterogeneities and experimental *** proposed model utilized hydro-mechanical spatial distributions,namely Young’s modulus and gas entry pressure,and elastoplasticity combined with a linear swelling model.A conceptual strain-dependent permeability approach simulated dilatancycontrolled gas flow based on hydro-mechanical *** test the effectiveness of the presented approach,a gas injection test in a compacted,saturated bentonite sample was simulated using the opensource code OpenGeoSys 5.8 and compared with experimental *** presented methodology is capable of simulating localized gas flow in preferential *** spatial distributions of Young’s modulus and gas entry pressure affect the swelling pressure,relative permeability and,in combination with the strain-dependent permeability model,also the intrinsic permeability.

关键词： H^(2)M coupling Gas migration Dilatancy-controlled flow Continuous approach Geomaterial heterogeneity OpenGeoSys

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A hazard analysis via an improved timed colored petri net with time–space coupling safety constraint

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Chinese Journal of Aeronautics 2016年第4期29卷 1027-1041页

作者： Li Zelin Wang Shihai Zhao Tingdi Liu Bin Science and Technology on Reliability and environmental Engineering Laboratory School of Reliability and Systems Engineering Beihang University

Petri nets are graphical and mathematical tools that are applicable to many systems for modeling, simulation, and analysis. With the emergence of the concept of partitioning in time and space domains proposed in avionics application standard software interface (ARINC 653), it has become difficult to analyze time–space coupling hazards resulting from resource partitioning using classical or advanced Petri nets. In this paper, we propose a time–space coupling safety constraint and an improved timed colored Petri net with imposed time–space coupling safety constraints (TCCP-NET) to fill this requirement gap. Time–space coupling hazard analysis is conducted in three steps: specification modeling, simulation execution, and results analysis. A TCCP-NET is employed to model and analyze integrated modular avionics (IMA), a real-time, safety-critical system. The analysis results are used to verify whether there exist time–space coupling hazards at runtime. The method we propose demonstrates superior modeling of safety-critical real-time systems as it can specify resource allocations in both time and space domains. TCCP-NETs can effectively detect underlying time–space coupling hazards. © 2016 Chinese Society of Aeronautics and Astronautics

关键词： Application programs Avionics Hazards Interactive computer systems Petri nets Resource allocation Safety engineering

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analysis for flow of Jeffrey fluid with nanoparticles

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Chinese Physics B 2015年第4期24卷 269-276页

作者： T.Hayat Sadia Asad A.Alsaedi Department of Mathematics Quaid-i-Azam University Nonlinear analysis and Applied Mathematics (NAAM) Research group Faculty of Science King Abdulaziz University

An analysis of the boundary layer flow and heat transfer in a Jeffrey fluid containing nanoparticles is presented in this paper. Here, fluid motion is due to a stretchable cylinder. The thermal conductivity of the fluid is taken to be temperature-dependent. The partial differential equations of velocity, temperature, and concentration fields are transformed to a dimensionless system of ordinary differential equations. Nonlinear governing analysis is computed for the homotopy solutions. The behaviors of Brownian motion and thermophoresis diffusion of nanoparticles have been examined graphi- cally. Numerical values of the local Nusselt number are computed and analyzed.

关键词： stretching cylinder Jeffrey nanofluid convergence

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Immobilization of self-assembled pre-dispersed nano-TiO_2 onto montmorillonite and its photocatalytic activity

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Journal of environmental Sciences 2015年第6期27卷 108-117页

作者： Tingting Zhang Yuan Luo Bing Jia Yan Li Lingling Yuan Jiang Yu Research group of environmental Catalysis & Separation Process College of Chemical Engineering Beijing University of Chemical Technology

The immobilization of pre-dispersed Ti O2 colloids onto the external surface of the clay mineral montmorillonite（Mt） was accomplished and regulated via a self-assembly method employing the cationic surfactant cetyltrimethylammonium bromide（CTAB）. The role of CTAB in the synthesis process was investigated by preparing a series of Ti O2-CTAB-Mt composites（TCM） with various CTAB doses. The results indicated that a uniform and continuous Ti O2 film was deposited on the external surface of montmorillonite in the composite synthesized with 0.1 wt.% of CTAB, and the TCM nano-composites showed much higher values for specific surface area, average pore size and pore volume than the raw montmorillonite clay. Then, the formed TCM materials were applied in photocatalytic degradation of 2,4-dichlorophenol（2,4-DCP） in aqueous solution. The degradation efficiency reached as high as 94.7%. Based on the degradation intermediates benezoquinone, fumaric acid and oxalic acid identified by LC-MS analysis, a mechanism for the photocatalytic oxidation of 2,4-DCP on Ti O2/Mt nano-composites is proposed.

关键词： Ti O2/Mt composite CTAB Immobilization Photocatalysis

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Application of a real-ambient fine particulate matter exposure system on different animal models

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Journal of environmental Sciences 2021年第7期33卷 64-70页

作者： Yuanyuan Song Lifang Zhao Zenghua Qi Yanhao Zhang Guodong Cao Ruijin Li Lin Zhu Zhu Yang Chuan Dong Zongwei Cai State Key Laboratory of environmental and Biological analysis Department of ChemistryHong Kong Baptist UniversityHong Kong SARChina Institute of environmental Science Shanxi UniversityTaiyuan 030006China School of environmental Science and Engineering Guangdong University of TechnologyGuangzhou 510006China

Simulation of fine particulate matter(PM_(2.5))exposure is essential for evaluating adverse health *** this work,an ambient exposure system that mimicked real atmospheric conditions was installed in Taiyuan,China to study impacts of chronic PM_(2.5) exposure on adult and aged mice as well as Sirtuin3 knockout(Sirt3 KO)mice and wild-type(WT)*** real-ambient exposure system eliminated the possible artificial effects caused from exposure experiments and maintained the physiochemical characteristics of PM_(2.5).The case studies indicated that aged mice exhibited apparent heart dysfunction involving in-creased heart rate and decreased blood pressure after 17-week of real-ambient PM_(2.5) ***,15-week of real-ambient PM_(2.5) exposure decreased the heart rate and amounts of associated catecholamines to induce heart failure in Sirt3 KO ***,the increased pro-inflammatory cytokines and decreased platelet related indices suggested that inflammation *** changes of biomarkers detected by targeted metabolomics confirmed metabolic disorder in WT and Sirt3 KO mice after exposed to real-ambient PM_(2.5).These results indicated that the real-ambient PM_(2.5) exposure system could evaluate the risks of certain diseases associated with air pollution and have great potential for support-ing the investigations of PM_(2.5) effects on other types of rodent models.

关键词： Real-ambient PM_(2.5)exposure system Adverse effects Sirt3 KO Aged mice

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Optimal Unification of Static and Dynamic Features for Smartphone Security analysis

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Intelligent Automation & Soft Computing 2023年第1期35卷 1035-1051页

作者： Sumit Kumar S.Indu Gurjit Singh Walia Scientific analysis group DRDODelhi110054India Delhi Technological University Delhi110042India

Android Smartphones are proliferating extensively in the digital world due to their widespread applications in a myriad *** increased popularity of the android platform entices malware developers to design malicious apps to achieve their malevolent ***,static analysis approaches fail to detect run-time behaviors of malicious *** address these issues,an optimal unification of static and dynamic features for smartphone security analysis is *** proposed solution exploits both static and dynamic features for generating a highly distinct unified feature vector using graph based cross-diffusion ***,a unified feature is subjected to the fuzzy-based classification model to distinguish benign and malicious *** suggested framework is extensively experimentally validated through both qualitative and quantitative analysis and results are compared with the existing *** evaluation over benchmarked datasets from Google Play Store,Drebin,Androzoo,AMD,and CICMalDroid2020 revealed that the suggested solution outperforms state-of-the-art *** achieve average detection accuracy of 98.62%and F1 Score of 0.9916.

关键词： Fusion smartphone android security analysis malware detection

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Comparison of Dissolved Air Flotation and Sedimentation in Treatment of Typical North China Source Water

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过程工程学报 2007年第2期7卷 283-287页

作者：刘善培王启山何文杰韩宏大樊雪红耿天甲 College of environmental Science and Engineering Nankai University Tianjin Water Works group Ltd.

The treatment of typical north China water by dissolved air flotation(DAF)and sedimentation process was examined.A pilot plant with a water treatment capacity of 120 m^3/d constructed in the Jieyuan Water Treatment Plant(JWTP) of Tianjin,China,was utilized for the comparison of the two *** results show that during the pilot test,DAF process can remove particles and organic mater more efficiently than sedimentation *** removal rate for turbidity by DAF process is 5.5% higher than that by sedimentation in normal turbidity period,and 40% higher in low turbidity period,it is 5%～10% higher for removals of algae,total organic carbon(TOC),trihalomethane formation potential(THMFP)and bacteria in all *** removal rates for turbidity,TOC,THMFP,algae and bacteria by DAF process can reach 95%,30%, 20%,94% and 97% *** the results of the pilot test,it can be concluded that DAF is a feasible clarification process,especially for source water with low turbidity and high algal blooming.

关键词：沉降浮力水利建设水利设施

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