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Grinding Chatter Detection and Identication Based on BEMD and LSSVM

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Chinese Journal of Mechanical Engineering 2019年第1期32卷 90-102页

作者： Huan-Guo Chen Jian-Yang Shen wen-Hua Chen chun-Shao Huang yong-Yu Yi Jia-Cheng Qian Zhejiang Province’s Key Laboratory of Reliability Technology for Mechanical and Electrical Product Hangzhou 310018 China Zhejiang Jiali Technology Co. Ltd. Hangzhou 311241 China Hangzhou Hangji Machine Tool Co. Ltd.Hangzhou 310018 China

Grinding chatter is a self?induced vibration which is unfavorable to precision machining processes. This paper proposes a forecasting method for grinding state identification based on bivarition empirical mode decomposition(BEMD) and least squares support vector machine(LSSVM), which allows the monitoring of grinding chatter over time. BEMD is a promising technique in signal processing research which involves the decomposition of two?dimen?sional signals into a series of bivarition intrinsic mode functions(BIMFs). BEMD and the extraction criterion of its true BIMFs are investigated by processing a complex?value simulation chatter signal. Then the feature vectors which are employed as an amplification for the chatter premonition are discussed. Furthermore, the methodology is tested and validated by experimental data collected from a CNC guideway grinder KD4020 X16 in Hangzhou Hangji Machine Tool Co., Ltd. The results illustrate that the BEMD is a superior method in terms of processing non?stationary and nonlinear signals. Meanwhile, the peak to peak, real?time standard deviation and instantaneous energy are proven to be e ec?tive feature vectors which reflect the di erent grinding states. Finally, a LSSVM model is established for grinding status classification based on feature vectors, giving a prediction accuracy rate of 96%.

关键词： Grinding chatter BEMD and LSSVM Complex-value chatter signal Feature vector Grinding status classification

Monte Carlo simulation of neutron sensitivity of microfission chamber in neutron flux measurement

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Nuclear Science and Techniques 2022年第6期33卷 128-138页

作者： Ze-Peng Wu Xin-Biao Jiang wen-Shou Zhang chun-Lei Su yong-Gang Zhang-Sun Li-Hong Bao State Key Laboratory of Simulation and Effect for Intense Pulse Radiation Northwest Institute of Nuclear TechnologyXi’an 710024China

Microfission chambers loaded with highly enriched fissile materials are widely used for measuring power in reactors. The neutron sensitivity of the microfission chamber is a key parameter that determines the accuracy of the power measurement. To evaluate the performance of the FC4A microfission chamber, in this work, we introduced an accurate and validated model of the microfission chamber, a performed Monte Carlo simulation of the neutron sensitivity of the microfission chamber with GEANT4 code, and conducted an irradiation experiment on the neutron irradiation effect platform #3 of the Xi’an Pulsed Reactor. We compared the simulated sensitivity with the experimental results, which showed that the sensitivity obtained from the simulation was in good agreement with the experimental results. In addition, we studied the impact of the design parameters of the fission chamber on the calculated neutron sensitivity of the microfission chamber.

关键词： Microfission chamber Neutron sensitivity Monte Carlo simulation GEANT4

Prophylaxis of chronic kidney disease after liver transplantation-experience from west China

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World Journal of Gastroenterology 2012年第9期18卷 991-998页

作者： Zhen-yong Shao Lu-Nan Yan wen-Tao Wang Bo Li Tian-Fu wen Jia-Yin Yang Ming-Qing Xu Ji-chun Zhao yong-Gang Wei Liver Transplantation Center Department of LiverSurgery West China Hospital of Sichuan University Chengdu610041 Sichuan Province China

AIM： TO evaluate the prophylaxis of chronic kidney dis- ease （CKD） after liver transplantation （LT） with low-dose calcineurin inhibitor （CNI） and mycophenolate mofetil （MMF）.

关键词： Liver transplantation Chronic kidney dis-ease Calcineurin inhibitor Mycophenolate mofetil Riskfactor

Effects of Anions and Cations on π-Complexation Between Olefin and Metal Halide

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Chemical Research in Chinese Universities 2005年第2期21卷 217-219页

作者： ZHOUJin-xia ZHANGyong-chun GUOXin-wen StateKeyLaboratoryofFineChemical DalianUniversityofTechnologyDalian116012P.R.China

An ab initio molecular orbital study was performed to determine the effects of anions and cations on the π-complexation of C_2H_4 on MX(M=Ag, Cu; X=F, Cl). The calculated results show the following order of adsorption strength: F ->Cl - for anions; Cu +>Ag + for cations. The results can be explained by the detailed analysis of atomic charge, orbital energy and orbital population by using the natural bond orbital(NBO) theory: (1) anions with stronger electronegativity can attract more electrons from the s orbital of M, while at the same time it does not obviously weaken the d orbital occupation of M, thus the nearly vacant s orbital and the sufficiently filled d orbitals of M help with forming σ-donation and d-π * backdonation with the π orbital and the π * orbital of olefin, respectively; (2) a smaller energy gap of symmetry-adapted orbitals between olefin and a cation can favor the electron transfer, that is why Cu + forms stronger adsorption with olefin than Ag + does.

关键词： Complexation ab initio Calculation Olefin Anion Cation

Geology, geochronology and geochemistry of large Duobaoshan Cu-Mo-Au orefield in NE China: Magma genesis and regional tectonic implications

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Geoscience Frontiers 2021年第1期12卷 265-292页

作者： wen-yan Cai Ke-yong Wang Jian Li Li-juan Fu chun-kit Lai Han-lun Liu College of Earth Sciences Jilin UniversityChangchun 130061China College of Geology and Mining Engineering Xinjiang UniversityUrumqi 830047China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and Resources of ChinaChangchun 130061China Technical Information Department Inner Mongolia Shandong Gold Geological Minerals Survey Co.Ltd.Chifeng 024000China Faculty of Science Universiti Brunei DarussalamGadongBrunei Darussalam

Duobaoshan is the largest porphyry-related Cu-Mo-Au orefield in northeastern(NE)Asia,and hosts a number of large-medium porphyry Cu(PCDs),epithermal Au and Fe-Cu skarn *** ages of these deposits,from the oldest(Ordovician)to youngest(Jurassic),have spanned across over 300 *** similar orefields of such size and geological complexity are found in NE Asia,which reflects its metallogenic uniqueness in forming and preserving porphyry-related *** this study,we explore the actual number and timing of magmatic/mineralization phases,their respective magma genesis,fertility,and regional tectonic connection,together with the preservation of *** present new data on the magmatic/mineralization ages(LA-ICP-MS zircon U-Pb,pyrite and molybdenite Re-Os dating),whole-rock geochemistry,and zircon trace element compositions on four representative deposits in the Duobaoshan orefield,i.e.,Duobaoshan PCD,Tongshan PCD,Sankuanggou Fe-Cu skarn,and Zhengguang epithermal Au deposits,and compiled published ones from these and other mineral occurrences in the *** terms of geochronology,we have newly summarized seven magmatic phases in the orefield:(1)Middle-Late Cambrian(506-491 Ma),(2)Early and Middle Ordovician(485-471 Ma and~462 Ma),(3)Late Ordovician(450-447 Ma),(4)Early Carboniferous and Late-Carboniferous to Early Permian(351-345 and 323-291 Ma),(5)Middle-Late Triassic(244-223 Ma),(6)Early-Middle and Late Jurassic(178-168 Ma and~150 Ma),and(7)Early Cretaceous(~112 Ma).Three of these seven major magmatic phases were coeval with ore formation,including(1)Early Ordovician(485-473 Ma)porphyry-type Cu-Mo-(Au),(2)Early-Middle Triassic(246-229 Ma)porphyry-related epithermal Au-(Cu-Mo),and(3)Early Jurassic(177-173 Ma)Fe-Cu skarn *** deposits in the orefield,notably Tongshan and Zhengguang,were likely formed by more than one mineralization *** terms of geochemistry,ore-causative granitoids in the orefield exhibit adakite-like or adakite-nor

关键词： Duobaoshan Cu-Mo-Au orefield(NE China) Porphyry Cu deposit Epithermal Au deposit Paleo-Asian Ocean Central Asian Orogenic Belt(CAOB)

Hydraulic experiment on mushroom head in bottom-blown smelting furnace

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Journal of Iron and Steel Research International 2017年第5期24卷 490-494页

作者： Fu-yong Su Zhi wen School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

There are many bottom-blown smelting furnaces in metallurgical industry. When oxygen or air sprays from the jet nozzle into the bottom of the furnace, the melting phase will be frozen and a hemispherical porous zone with a mushroom head shape will be formed around the nozzle. The mushroom head can pro- tect the jet nozzle and mitigate the liquid spray on the surface of melt. In order to analyze the formation process of a mushroom head in the bottom-blown smelting furnaces, a hydraulic experiment system was designed and the formation of the mushroom head was investigated by hydraulic experiment. The hydrau- lic experiment results show that the formation process is mainly divided into generating crushing genera- ting process and stable mushroom head generation process. The formation of stable mushroom head re- quires certain thermodynamic condition and water splash is more intense without a mushroom head than with a mushroom head. The size, porosity and diameter of the mushroom head are affected by the flow rate, temperature and heat capacity of the bottom-blowing gas and the temperature of the superheat and the physical parameters of the melt.

关键词： Bottom-blown smelting furnace Mushroom head Hydraulic experiment Thermal equilibrium Similarity criterion

Spatial variability of soil hydraulic conductivity and runoff generation types in a small mountainous catchment

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Journal of Mountain Science 2020年第11期17卷 2724-2741页

作者： YANG yong CHEN Ren-sheng SONG Yao-xuan HAN chun-tan LIU Zhang-wen LIU Jun-feng Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecohydrology Inland River BasinNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China

As an important soil property,saturated hydraulic conductivity(Ks)controls many hydrological processes,such as runoff generation types,soil moisture storage and water *** of the extremely harsh natural environmental conditions and soil containing a significant fraction of gravel fragments in high-elevation mountainous catchments,the measurement data of Ks and other soil properties are seriously lacking,which leads to poor understanding on its hydrological processes and water *** this study,the vertical variation(0-150 cm)of Ks and other soil properties from 38 soil profiles were measured under five different land cover types(alpine barren,forest,marshy meadow,alpine shrub and alpine meadow)in a small catchment in Qilian Mountains,northwestern China.A typical characteristic of soil in mountainous areas is widespread presence of rock and gravel,and the results showed that the more rock and gravel in the soil,the higher Ks and bulk density and the lower the soil capillary porosity,field water capacity and total *** Ks of the lower layer with rock and gravel(18.49±10.22 mm·min-1)was significantly higher than that of the upper layer with relatively fine textured soil(0.18±0.18 mm·min-1).The order of values of the Ks in different land cover types was alpine barren,forest,alpine shrub,marshy meadow and alpine meadow,and the values of the Ks in the alpine barren were significantly higher than those of other land *** rainfall events in the research catchment had low rain intensity(<0.04 mm·min-1),and deep percolation(DP)was the dominant runoff generation *** the rainfall intensity increased(0.11 mm·min-1),subsurface stormflow(SSF)appeared in the alpine *** excess overland flow(IOF),SSF and DP existed simultaneously only when the rainfall intensity was extremely high(1.91 mm·min-1).IOF and SSF were almost never appeared in the alpine barren because of high *** alpine barren was the main runoffcontributed area in the

关键词： Saturated hydraulic conductivity Rock fragment Land cover Runoff generation Mountain catchment

Recent Advances in High‑Efficiency Electrocatalytic Water Splitting Systems

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Electrochemical Energy Reviews 2023年第1期6卷 1-38页

作者： Xian‑Wei Lv wen‑wen Tian Zhong‑yong Yuan Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin 300350China

Electrocatalytic water splitting driven by renewable energy input to produce clean hydrogen(H_(2))has been widely considered a prospective approach for a future hydrogen-based ***,the development of industrial alkaline water electrolyzers is hindered due to their unfavorable thermodynamics with high overpotential for delivering the whole process,caused by sluggish kinetics involving four-electron *** exploration of water electrolysis with low energy consumption and high efficiency is urgently required to meet the ever-growing energy storage and portfolio *** review emphasizes the strategies proposed thus far to pursue high-efficiency water electrolysis systems,including from the aspects of electro-catalysts(from monofunctional to bifunctional),electrode engineering(from powdery to self-supported),energy sources(from nonrenewable to renewable),electrolytes(from pure to hybrid),and cell configurations(from integrated to decoupled).Critical appraisals of the pivotal electrochemistry are highlighted to address the challenges in elevating the overall efficiency of water ***,valuable insights for the future development directions and bottlenecks of advanced,sustainable,and high-efficiency water splitting systems are outlined.

关键词： Electrocatalytic water splitting Hydrogen-based society Electrode engineering Cell configurations Challenges and perspectives

Study on parameters influencing analytical performance of laser-induced breakdown spectroscopy

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Frontiers of physics 2012年第6期7卷 714-720页

作者： yong Zhang Yun-Hai Jia Jin-wen Chen Xue-Jing Shen Lei Zhao chun Yang yong-Yan Chen yong-Hui Zhang Peng-Cheng Han National Analysis Center for Iron and Steel Central Iron&Steel Research InstituteBeijing 100081China

Lens-to-sample distances, delay time, atmospheric condition, laser pulse energy, etc. had obvious effects on the analytical performance of laser-induced breakdown spectroscopy. In this paper, these parameters are investigated in greater detail and we will explain how they have influences on the analytical performance. The results show that the focal plane under the sample surface can improve precision and detection limit, and the delay time should be decided according to sensitivity and accuracy. Spectral line intensity is stronger in argon than helium, nitrogen and air gas environment. Pulse energy should exceed energy threshold （about 50 m J） which can generate plasma, and the energy should not exceed about 300 mJ to avoid plasma shielding. Under optimum parameters, concentration relative standard deviation of C, Si, Mn, P, S, Ni, and Cr for low-alloyed steel （sample number 11278） which were measured 11 times is 2.37%, 2.18%, 2.23%, 7.8%, 9.34%, 1.92%, and 2.13%, respectively. And the detection limit of C, Si, Mn, P, S, Ni, and Cr for pure steel is 0.0045%, 0.0072%, 0.0069%, 0.0027%, 0.0024%, 0.0047%, and 0.0024%, respectively.

关键词： laser-induced breakdown spectroscopy (LIBS) analytical performance plasma diagno- sis plasma shielding