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Crack Fault Classification for Planetary Gearbox Based on Feature Selection Technique and K-means Clustering Method

Chinese Journal of Mechanical Engineering 2018年第1期31卷 242-252页

作者： li-ming wang Yi-Min Shao State Key Laboratory of Mechanical Transmission Chongqing University

During the condition monitoring of a planetary gearbox, features are extracted from raw data for a fault ***, different features have different sensitivity for identifying different fault types, and thus, the selection of a sensitive feature subset from an entire feature set and retaining as much of the class discriminatory information as possible has a directly effect on the accuracy of the classification results. In this paper, an improved hybrid feature selection technique(IHFST) that combines a distance evaluation technique(DET), Pearson’s correlation analysis, and an ad hoc technique is proposed. In IHFST, a temporary feature subset without irrelevant features is first selected according to the distance evaluation criterion of DET, and the Pearson’s correlation analysis and ad hoc technique are then employed to find and remove redundant features in the temporary feature subset, respectively, and hence,a sensitive feature subset without irrelevant or redundant features is selected from the entire feature set. Further, the k-means clustering method is applied to classify the different kinds of health conditions. The effectiveness of the proposed method was validated through several experiments carried out on a planetary gearbox with incipient cracks seeded in the tooth root of the sun gear, planet gear, and ring gear. The results show that the proposed method can successfully distinguish the different health conditions of a planetary gearbox, and achieves a better classification performance than other methods. This study proposes a sensitive feature subset selection method that achieves an obvious improvement in terms of the accuracy of the fault classification.

关键词： Planetary gearbox Gear crack Feature selection technique K-means classification

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Study on supported combined liquid membrane containing HEH(EH)P and HNO_3 for trivalent gadolinium transfer

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Chinese Chemical Letters 2011年第9期22卷 1095-1098页

作者： liang Pei li ming wang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Faculty of Water Resources and Hydraulic Power Xi'an University of Technology Xi'an 710048 China

A novel kind of supported combined liquid membrane （SCLM） has been studied for the Gd（IIl） transfer. SCLM contained polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and renewal solution including HNO3 solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （HEH（EH）P） as the carrier dissolved in kerosene. The mixed solution of carrier and kerosene was membrane solution. The optimum transport conditions of Gd（III） were that concentration of HNO3 solution was 4.00 tool/L, concentration of carrier was 0.16 mol/L, and volume ratio of membrane solution to stripping solution was 30：30 of the renewal phase, and pH value was 4.80 of the feed phase. Under the optimum condition studied, when initial concentration of Gd（III） was 1.00 × 10^-4 mol/L, the transfer rate of Gd（III） was 96.8% during 130 min.

关键词： Supported combined liquid membrane 2-Ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester Renewal phase Gadolinium

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Synthesis, Crystal Structure and Biological Activity of 2-Chloro-N-{2-fluoro-5-[N-(phenylsulfonyl) phenyl-sulfonamido]phenyl}benzamide

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Chemical Research in Chinese Universities 2008年第3期24卷 295-298页

作者： li Wen-ming wang Jian-guo li Zheng-ming SONG Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry National Pesticide Engineering Research Center Nankai University Tianjin 300071 P R. China

2-Chloro-N-{2-fluoro-5-[N-（phenylsulfonyl）phenylsulfonamido]phenyl}benzamide was synthesized and its crystal structure was also determined by X-ray single-crystal diffraction. The title compound（C25H18ClFN2O5S2） belongs to monoclinic, space group P21/n with a=0.7377（3） nm, b=1.2036（5） nm, c=2.6846（11） nm, β=90.895（9）°, V=2.3833（16） nm3, Mr=544.98, Z=4, Dc=1.519 g/cm3, μ=0.385 mm–1, F（000）=1120, R1=0.0632, and wR2=0.1438. Its crystal structure belongs to a novel class that has not been reported yet, and its preliminary herbicidal activity was also tested. Its inhibition rate to seedling growth of barnyard grass reaches 15.1% at 100 μg/mL.

关键词： X-ray diffraction Crystal structure Synthesis Biological activity

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Stripping dispersion hollow fiber liquid membrane containing carrier PC-88A and HNO_3 for the extraction of Sm^(3+)

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Chinese Chemical Letters 2012年第1期23卷 101-104页

作者： liang Pei li ming wang Wei Guo Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Environment and Chemistry Engineering Xi'an Polytechnic UniversityXi'an 710048China Faculty of Water Resources and Hydraulic Power Xi'an University of TechnologyXi'an 710048China

Stripping dispersion hollow fiber liquid membrane system（SDHFLM） containing feed phase adding acetate buffer solution and dispersion solution with HNO_3 solution as the stripping solution and membrane solution of 2-ethyl hexyl phosphoric acid-mono-2-ethylhexyl ester（PC-88A） dissolved in kerosene,has been studied for the extraction of Sm^（3＋）.Many factors including pH value, volume ratio of membrane solution to stripping solution（OAV） and carrier concentration on Sm^（3＋） extraction were investigated. Experimental results indicate that the optimum extraction conditions of Sm^（3＋） were obtained as that PC-88A concentration was 0.120 mol/L,and OAV was 1.00 in the dispersion phase,and pH value was 4.80 in the feed *** initial Sm^（3＋） concentration was 1.20×10^（-4） mol/L,the extraction percentage of Sm^（3＋） was up to 92.8%in 160 min.

关键词： Stripping dispersion hollow fiber liquid membrane 2-Ethyl hexyl phosphoric acid-mono-2-ethyl hexyl ester Samarium Dispersion phase Extraction flux Extraction rate

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Reaction Kinetics of Trans-Sobrerol and 8-p-Menthen-1,2-diol with Hydroxyl Radical in Aqueous Solution： A Combined Experimental and Theoretical Study

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Chinese Journal of Chemical Physics 2015年第3期28卷 308-314,I0001,I0002页

作者： Yan Long Xin Tong Tong-mei Ma li-ming wang School of Chemistry & Chemical Engineering South China University of Technology Guangzhou 510640 China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control South China University of Technology Guangzhou 510006 China

Trans-sobrerol （Sob） and 8-p-menthen-1,2-diol （limo-diol） are the primary products in the atmospheric oxidation of α-pinene and limonene, respectively. Because of their low volatility, they associate more likely to the liquid particles in the atmosphere, where they are subject to the aqueous phase oxidation by the atmospheric oxidants. In this work, through experimental and theoretical study, we first provide the rate constants of Sob and limo-diol reacting with hydroxyl radical （.OH） in aqueous solution at room temperature of 3044-3 K and 1 atm pressure, which are （3.05±0.5）×10 9 and （4.57±0.2）×10 9 L/（mol.s）, respectively. Quantum chemistry calculations have also been employed to demonstrate the solvent effect on the rate constants in aqueous phase and the calculated results agree well with the measurements. Some reaction products have been identified based on liquid chromatography combined with mass spectroscopy and theoretical calculations.

关键词： Unsaturated alcohols Hydroxyl radical Aqueous-phase reaction Kinetic Theoretical calculations

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Molecular Recognition Based on Hydrogen-bonding in the Coliposomes of Phosphatidylcholine and Amphiphiles Using Nucleobases

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Chemical Research in Chinese Universities 2006年第6期22卷 803-807页

作者： SONG li-ming ZHU Tao wang Qiu-sheng ZHANG Xiao li Guo-wen Key Lab for Supramolecular Structure and Materials of Ministry of Education Jilin University Changchun 130012 P. R. China

A functional amphiphile, N^6 -myristoyl-9-[ 8-（ 1-trimethylamino） octyl ] adenine bromide （MTOAB）, was used to form coliposomes of phosphatidyleholine（PC）, PC/thymine, and PC/TOTB using sonication . The morphologies of the coliposomes were characterized using TEM （transmission electron microscopy）. The UV-Vis spectroscopic behavior of PC/MTOAB/thymine （molar ratio = 5： 1： 1 ） and PC/MTOAB/TOTB （molar ratio = 5： 1： 1 ） of coliposomal solutions showed that as a result of base pairing, absorption intensity showed a decrease at 263 nm with increase of time. The decrease of absorption intensity is ascribed to the hypochromic effect, which is because of the formation of hydrogen bonds between adenine and thymine in the coliposomes. The same effect was also observed for the mixture of aqueous PC/MTOAB liposomes and PC/TOTB liposomes after fusion, whereas the nocomplementary coliposomcs formed from PC/MTOAB and PC/TOTB did not show these spectroscopic changes. The molecular recognition through hydrogen interactions between adenine and thymine is very slow because of the possible occurrence of molecular lateral diffusion and exchange of amphiphile before recognition progresses in coliposomes. These results provide useful information for the design of supramolecular devices such as vesicles and liposomes,which can be used to mimic primitive recognition processes observed in biological systems.

关键词： Coliposomes Nueleobase Molecular recognition Amphiphile

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Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance

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Agricultural Sciences in China 2009年第10期8卷 1246-1255页

作者： YUAN Wei-ling CAO Cou-gui li Cheng-fang ZHAN ming CAI ming-li wang Jin-ping Crop Physiology and Production Center （CPPC） Huazhong Agricultural University~Key Laboratory of Huazhong Crop PhysiologyEcology and Production Ministry of Agriculture Wuhan 430070 P.R China

Rice-duck （RD） and rice-fish （RF） ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane （CH4） and nitrous oxide （N2O） emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials （GWPs）, we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly （P〈 0.05） lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly （P〈0.05） higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK （5 997.6 and 5 391.5 RMB yuan ha^-1）. Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits.

关键词： methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem,greenhouse effect economic benefit

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Post-transcriptional gene silencing signal could move rapidly and bidirectionally in grafted Arabidopsis thaliana

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Chinese Science Bulletin 2006年第3期51卷 313-319页

作者： li ming JIANG Shiling wang Youqun liU Guoqin State Key Laboratory of Plant Physiology and Biochemistry College ofBiological Sciences China Agricultural University Beijing 100094China

RNA interference (RNAi), one of the newly found ways for post-transcriptional gene si- lencing, has been widely used to investigate gene functions through transgenic methods for introducing an RNA silencing signal into plants. In the present study, we constructed a dexamethazone (DEX)-inducible RNAi binary vector harboring a specific sequence fragment (168-bp) homologous to KatB and KatC, two kinesin isoform genes of Arabidopsis, which were proved to result in the post-transcriptional gene si- lencing of KatB and KatC in DEX-induced transgenic plants. RT-PCR and Northern blot analysis on trans- genic homozygous Arabidopsis (termed as RNAi-type plants) showed that DEX inducement causes KatB and KatC mRNA degradation. With a simplified method, Arabidopsis grafting was effectively per- formed between RNAi-type and wild-type lines. The target gene mRNA levels were tested based on semi-quantitative RT-PCR. Our results demonstrateed that DEX-induced gene silencing signals could result in a reduction in KatB and KatC mRNA in the wild-type rootstocks or scions, indicating that silencing signals of RNAi could be transmitted bidirectionally across the graft junction whether RNAi-plants were scions or stocks. In contrast to the previously reported results on grafted tobacco, the transmission of post- tran- scriptional gene silencing signals caused by RNAi in grafted Arabidopsis is more effective than that in to- bacco.

关键词：阿布属嫁接 RNA干预基因抑制信号传导烟草

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Bonding Interface Imaging and Shear Strength Prediction by Ultrasound1

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Chinese Physics Letters 2010年第6期27卷 118-121页

作者： li Yong-An MAO Jie li ming-Xuan wang Xiao-Min AN Zhi-Wu ZHUANG Qiao State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190

The propagation of a longitudinal ultrasonic wave normally incident upon an adhesively bonded structure is stud- ied. The structure consists of adherend and adhesive layers with finite thickness. Interfaces between adherend and adhesive are regarded as distributed springs. Theoretical and experimental results show that resonant frequencies of the bonded structure vary sensitively with the interface stiffness constants and adhesive thickness, and these interface characteristics are inversed by the simulation annealing （SA） method. Furthermore, the distribution image of interface stiffnesses is compared with the state of fracture interface, and quantitative prediction of shear strength is achieved based on the distribution of interface stiffnesses and adhesive thicknesses by using a back- propagation neutral network. The average relative error of the shear strength from prediction to real value is 10.7%.

关键词： Adhesives Stickiness Shears Strength Forecasting Shearing Thickness Economic distribution

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Genetic diversity and a population structure analysis of accessions in the Chinese cowpea [Vigna unguiculata(L.)Walp.]germplasm collection

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The Crop Journal 2017年第5期5卷 363-372页

作者： Honglin Chen Hong Chen liangliang Hu lixia wang Suhua wang ming li wang Xuzhen Cheng National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop Science Chinese Academy of Agricultural Sciences Development Center of Science and Technology Ministry of Agriculture PR China United States Department of Agriculture Agricultural Research Service Plant Genetic Resources Conservation Unit

Cowpea(Vigna imguicuiata) is an important legume crop with diverse uses. The species is presently a minor crop, and evaluation of its genetic diversity has been very limited. In this study, a total of 200 genic and 100 genomic simple sequence repeat(SSR) markers were developed from cowpea unigene and genome sequences, respectively. Among them, 27 genic and 27 genomic SSR markers were polymorphic and were used for assessment of genetic diversity and population structure in 105 selected cowpea accessions. A total of 155 alleles and 2.9 alleles per marker were identified, and the average polymorphic information content(PIC) value was 0.3615. The average PIC of genomic SSRs(0.3996) was higher than that of genic SSRs(0.3235), and most of the polymorphic genomic SSRs were composed of di-and trinucleotide repeats(51.9% and 37.0% of all loci, respectively). The low level of detected genetic diversity may be attributed to a severe genetic bottleneck that occurred during the cowpea domestication process. The accessions were classified by structure and cluster analysis into four subgroups that correlated well with their geographic origins or collection sites. The classification results were also consistent with the results from principal coordinate analysis and can be used as a guide during future germplasm collection and selection of accessions as breeding materials for cultivar improvement. The newly developed genic and genomic SSR markers described in this study will be valuable genomic resources for the assessment of genetic diversity, population structure, evaluation of germplasm accessions, construction of genetic maps, identification of genes of interest,and application of marker-assisted selection in cowpea breeding programs.

关键词： Vigna unguiculata (L.) Walp Cultivated cowpea collection Microsatellite marker Genetic diversity Population structure

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