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Preliminary study on treatment of waste organic matter from livestock by bacteria-mineral technology

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Journal of Environmental Sciences 2008年第6期20卷 646-651页

作者： HE Wenyuan YANG Haizhen GU guowei State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Shanghai Environment Group Company Limited Shanghai 200336 China

The present study dealt with relationships between the degradation and humification process that the organic matter underwent during bacteria-mineral technology. An inverse correlation was found between the protein, lipid, and some of the humification indices considered, suggesting that the humification theory is actually humic substances produced from simple-structured natural organic substrates. Weight-average molecular weight （Mw）, number-average molecular weight （Mn）, and the ratio Mw/Mn of dissolved organic matters at different stages of the process were measured by gel permeation chromatography. The results showed that Mn and Mw increased with reaction time from 352 to 17,191, and from 78,707 to 104,564, respectively. The ratio of Mn/Mw decreased from 223.3 to 6.1. This reflected the growth of the polymerization degree of dissolvable organic matters in the process; furthermore, it indicated the formation of complex molecules （humic substances） from more simple molecules. Bacteria-mineral water （BMW）（the effluent of the process） treatments can exert hormone-like activity for enhanced seed germination of wheat and rice and greatly improved chlorophyll synthesis in wheat and rice leaves, Major polyamines （plant regulators） putrescine, spermidine, and spermine, were found in BMW by a high performance liquid chromatography （HPLC） method, which may explain the hormone-like activity of BMW.

关键词： livestock liquid wastes treatment bacteria-mineral technology recycles humification biogenic amines seed germination

Extracting inter-area oscillation modes using local measurements and data-driven stochastic subspace technique

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Journal of Modern Power Systems and Clean Energy 2017年第5期5卷 704-712页

作者： Deyou YANG guowei CAI Kevin CHAN School of Electrical Engineering Northeast Dianli UniversityJilinChina Department of Electrical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongSARChina

In this paper, a data-driven stochastic subspace identification(SSI-DATA) technique is proposed as an advanced stochastic system identification(SSI) to extract the inter-area oscillation modes of a power system from wide-area measurements. For accurate and robust extraction of the modes’ parameters(frequency, damping and mode shape), SSI has already been verified as an effective identification algorithm for output-only modal *** new feature of the proposed SSI-DATA applied to inter-area oscillation modal identification lies in its ability to select the eigenvalue automatically. The effectiveness of the proposed scheme has been fully studied and verified,first using transient stability data generated from the IEEE16-generator 5-area test system, and then using recorded data from an actual event using a Chinese wide-area measurement system(WAMS) in 2004. The results from the simulated and recorded measurements have validated the reliability and applicability of the SSI-DATA technique in power system low frequency oscillation analysis.

关键词： Data-driven stochastic subspace identification(SSI-DATA) Power system inter-area oscillation Widearea measurement systems(WAMS) Modal analysis

Physical Characteristics of Welding Arc Ignition Process

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 786-791页

作者： SHI Linan SONG Yonglun XIAO Tianjiao RAN guowei College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Beijing 100124 China

The existing research of welding arc mainly focuses on the stable combustion state and the research on the mechanism of welding arc ignition process is quite *** tungsten inert gas（TIG） touch arc ignition process is observed via a high speed camera and the high time resolution spectral diagnosis *** changing phenomenon of main ionized element provided the electrons in the arc ignition is *** metallic element is the main contributor to provide the electrons at the beginning of the discharging,and then the excitated shielding gas element replaces the function of the metallic *** electron density during the period of the arc ignition is calculated by the Stark-broadened lines of Hα.Through the discussion with the repeatability in relaxation phenomenon,the statistical regularity in the arc ignition process is *** similar rules as above are observed through the comparison with the laser-assisted arc ignition experiments and the metal inert gas（MIG） arc ignition *** research is helpful to further understanding on the generation mechanism of welding arc ignition and also has a certain academic and practical significance on enriching the welding physical theoretical foundation and improving the precise monitoring on automatic arc welding process.

关键词： welding arc ignition process physical characteristic spectral diagnosis

Observer-based adaptive fuzzy output constrained FTC for nonlinear interconnected large-scale systems

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Science China(Information Sciences) 2020年第1期63卷 253-255页

作者： guowei DONG Liang CAO Hongyi LI School of Automation and Guangdong Province Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of Technology

Dear editor,The problem of fault usually cannot be ignored in actuator control systems. Once the faults are unresolved, the stability and dynamic performance of controlled systems are incapable of being guaranteed. Accordingly, some fault-tolerant control(FTC) methods for nonlinear systems have been proposed on the basis of a backstepping framework [1].

关键词： Observer-based adaptive fuzzy output constrained FTC for nonlinear interconnected large-scale systems FTC

Lattice Boltzmann simulations of high-order statistics in isotropic turbulent flows

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Applied Mathematics and Mechanics(English Edition) 2018年第1期39卷 21-30页

作者： Guodong JIN Shizhao WANG Yun WANG guowei HE Stake Key Laboratory of Nonlinear Mechanics (LNM) Institute of MechanicsChinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

The lattice Boltzmann method （LBM） is coupled with the multiple-relaxation- time （MRT） collision model and the three-dimensional 19-discrete-velocity （D3Q19） model to resolve intermittent behaviors on small scales in isotropic turbulent flows. The high- order scaling exponents of the velocity structure functions, the probability distribution functions of Lagrangian accelerations, and the local energy dissipation rates are investi- gated. The self-similarity of the space-time velocity structure functions is explored using the extended self-similarity （ESS） method, which was originally developed for velocity spatial structure functions. The scaling exponents of spatial structure functions at up to ten orders are consistent with the experimental measurements and theoretical results, implying that the LBM can accurately resolve the intermittent behaviors. This valida~ tion provides a solid basis for using the LBM to study more complex processes that are sensitive to small scales in turbulent flows, such as the relative dispersion of pollutants and mesoscale structures of preferential concentration of heavy particles suspended in turbulent flows.

关键词： mesoscopic modelling lattice Boltzmann method (LBM) isotropic turbulent flow structure function intermittency high-order statistics self-similarity

A review on effects of different factors on gas explosions in underground structures

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Underground Space 2020年第4期5卷 298-314页

作者： Ying Xu Yimiao Huang guowei Ma School of Civil and Transportation Engineering Hebei University of Technology5340 Xiping RoadBeichen DistrictTianjinChina Department of Civil Environmental and Mining EngineeringUniversity of Western Australia35 Stirling HighwayCrawleyWAAustralia

Underground structures are normally located in highly-confined and congested spaces,which may lead to severe gas explosion accidents,with significant human and economic *** accurately evaluating the consequences of these explosions,a variety of influencing factors need to be considered,including concentrations of gas mixtures,vent conditions,obstacles,and ignition ***,a good review on these influencing factors is important for a better understanding of explosion behavior,e.g.,the deflagration to detonation *** this study,some critical influencing factors for gas explosions in underground or confined spaces are investigated,and the effects of the factors on such gas explosions are *** results are discussed,along with findings from *** present study provides a reference for future studies on safety management and consequence mitigation for underground gas explosions.

关键词： Gas explosion Gas concentration Ventilation Obstacle Ignition feature Detonation

Damage Evolution and Crack Propagation in Semicircular Bending Asphalt Mixture Specimens

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Acta Mechanica Solida Sinica 2016年第6期29卷 596-609页

作者： guowei Zeng Xinhua Yang Long Chen Fan Bai School of Civil Engineering and Mechanics Huazhong University of Science and Technology School of Science Wuhan University of Science and Technology

The damage and fracture behaviors of semicircular bending （SCB） asphalt mixture specimens with different orientation notches are experimentally and numerically investigated. In the numerical simulations, asphalt mixture is modeled as a two-phase material, namely a mix of coarse aggregates and asphalt mastic, and the mechanical behavior of asphalt mastic is charac- terized with the damage constitutive model and the damage-based fracture criterion. Some SCB experiments are performed on the asphalt mixture specimens with different orientation notches to validate the numerical method. Finally, the effects of notch orientation and aggregate distrib- ution on crack path, damage distribution, and the load vs. displacement relation are numerically evaluated.

关键词： semicircular bending heterogeneous model damage notch orientation

Oil Crops:A Potential Source of Biodiesel

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Engineering 2023年第10期29卷 39-41页

作者： Zhenhui Yan guowei Li Shubo Wan Institute of Crop Germplasm Resources Shandong Academy of Agricultural SciencesJinan 250100China Shandong Provincial Key Laboratory of Crop Genetic Improvement Ecologyand PhysiologyJinan 250100China College of Agriculture Hunan Agricultural UniversityChangsha 410127China

*** Oil crops such as soybeans,sunflower,canola,rapeseed,and peanuts play a vital role in the agricultural economy,second only to food crops in terms of area and *** oil is known for its high energy density,containing approximately 2.25 times more calories per unit mass than carbohydrates or ***,vegetable oil is an important source of energy and provides a variety of fatty acids necessary for human health.

关键词： crops vital soybean

Independent component analysis of streamwise velocity fluctuations in turbulent channel flows

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Theoretical & Applied Mechanics Letters 2022年第4期12卷 233-240页

作者： Ting Wu guowei He The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

Independent component analysis(ICA)is used to study the multiscale localised modes of streamwise velocity fluctuations in turbulent channel *** aims to decompose signals into independent modes,which may induce spatially localised *** height and size are defined to quantify the spatial position and extension of these ICA modes,*** contrast to spatially extended proper orthogonal decomposition(POD)modes,ICA modes are typically localised in space,and the energy of some modes is distributed across the near-wall *** sizes of ICA modes are multiscale and are approximately proportional to their *** modes can also help to reconstruct the statistics of turbulence,particularly the third-order moment of velocity fluctuations,which is related to the strongest Reynolds shear-stressproducing *** results reported in this paper indicate that the ICA method may connect statistical descriptions and structural descriptions of turbulence.

关键词： Independent component analysis Turbulent channel flow Proper orthogonal decomposition Third-order moment Localised modes