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Communications in Theoretical Physics 2007年第5期47卷 875-878页

作者： duan yi-Shi REN Ji-Rong LI Ran Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper, spinor and vector decompositions of SU（2） gauge potential are presented and their equivalence is constructed using a simply proposal. We also obtain the action of Faddeev nonlinear 0（3） sigma model from the SU（2） mass/ve gauge field theory, which is proposed according to the gauge invariant principle. At last, the knot structure in SU（2） Chern-Simons filed theory is discussed in terms of the Φ-mapping topological current theory, The topological charge of the knot is characterized by the Hopf indices and the Brouwer degrees of Φ-mapping.

关键词： SU(2) gauge potential decomposition massive gauge theory Chern-Simons knot

BP neural network model on the forecast for blasting vibrating parameters in the course of hole-by-hole detonation

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Journal of Coal Science & Engineering(China) 2010年第3期16卷 249-255页

作者： duan Bao-fu LI Jun-meng ZHANG meng College of Civil Engineering and Architecture Shandong University of Science and Technology Qingdao 266510 China Civil Engineering Laboratory of Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdao 266510 China

According to the neural network theory, combined with the technical characteristicsof the hole-by-hole detonation technology, a BP network model on the forecast forblasting vibration parameters was *** the deep hole stair demolition in a mine asan experimental object and using the raw information and the blasting vibration monitoringdata collected in the process of the hole-by-hole detonation, carried out some training andapplication work on the established BP network model through the Matlab software, andachieved good *** computed the vibration parameter with the empirical formulaand the BP network model *** comparing with the actual value, it is discoveredthat the forecasting result by the BP network model is close to the actual value.

关键词： blasting vibration BP neural network detonation hole-by-hole prediction model

An approach for shape optimization of stratosphere airships based on multidisciplinary design optimization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1609-1616页

作者： Ouan-bao WANG Ji-an CHEN Gong-yi FU Deng-ping duan Institute of Aerospace Science & Technology Shanghai Jiao Tong University Shanghai 200240 China

Airship shape is crucial to the design of stratosphere airships. In this paper, multidisciplinary design optimization (MDO) technology is introduced into the design of airship shape. We devise a composite objective function, based on this technology, which takes account of various factors which influence airship performance, including aerodynamics, structures, energy and weight to determine the optimal airship shape. A shape generation algorithm is proposed and appropriate mathematical models are constructed. Simulation results show that the optimized shape gives an improvement in the value of the composite objective function compared with a reference shape.

关键词： Airship shape Multidisciplinary design optimization (MDO) Adaptive simulation annealing Stratosphere airship

Size effect of lattice material and minimum weight design

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Acta Mechanica Sinica 2014年第2期30卷 191-197页

作者： Jun Yan Wen-Bo Hu Zhen-Hua Wang Zun-yi duan Dalian University of Technology

The size effects of microstructure of lattice materials on structural analysis and minimum weight design are studied with extented multiscale finite element method（EMsFEM） in the paper. With the same volume of base material and configuration, the structural displacement and maximum axial stress of micro-rod of lattice structures with different sizes of microstructure are analyzed and *** is pointed out that different from the traditional mathematical homogenization method, EMsFEM is suitable for analyzing the structures which is constituted with lattice materials and composed of quantities of finite-sized *** minimum weight design of structures composed of lattice material is studied with downscaling calculation of EMsFEM under stress constraints of micro-rods. The optimal design results show that the weight of the structure increases with the decrease of the size of basic sub-unit cells. The paper presents a new approach for analysis and optimization of lattice materials in complex engineering constructions.

关键词： Lattice material Light weight design Size ef-fect Extented multiscale finite element method

Theoretical elastoplastic analysis for foundations with geosynthetic-encased columns

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第7期13卷 506-518页

作者： Yuan-yu duan yi-ping ZHANG Dave CHAN Ya-nan YU College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaCanada

As a new technique in ground improvement, geosynthetic-encased columns (GECs) have promising applications in soft soil foundation. By assuming yielding occurs in the columns while the surrounding soil and the geosynthetic remain elastic, an elastoplastic analytical procedure for foundations improved by GECs is proposed. The radial stresses that the geosynthetic provides and the elastoplastic deformations of the foundation resting on a rigid base are derived. A comparison with finite element analysis shows that the proposed method is effective and can provide a reasonable prediction of a GEC's deformation. Subsequent parametric analysis indicates that higher geosynthetic stiffness leads to better performance of the composite foundation. The optimum length of encasement is related to the load acting on the foundation and the permissible vertical and radial displacements of the column. Moreover, as the dilation angle of the column increases, the settlement decreases, especially under high loading. The influence of the encasement is more significant in soils with smaller elastic modulus.

关键词： Geosynthetic-encased columns (GECs) Equal vertical strain Elastoplastic deformation Analytical procedure

SO_2 emission cap planning for Chengdu-Chongqing economic zone

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Journal of Environmental Sciences 2012年第1期24卷 142-146页

作者： Peng yi Ning duan Fahe Chai Yaxuan Xu Youjiang He State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

The SO 2 emission sources of the Chengdu-Chongqing economic zone were divided into 556 emissions units according to four different categories,which are city,industry,point sources,and area *** CALPUFF model was used to calculate the contribution of each unit,and consequently obtain an influence-transferring *** ensure that the SO 2 concentrations of 46 cities and counties in the Chengdu-Chongqing economic zone meet air quality standards,an emission optimization model was developed to calculate optimal emissions of each emission unit under different development *** result showed the optimal emissions of SO 2 by different provinces and *** achieve the target of restricting and optimizing development,corresponding planning programs were developed for every district.

关键词： Chengdu-Chongqing economic zone SO2 emission cap planning optimal distribution.

Selective Oxidation of PM over Li Doped Potassium Titanate Catalysts

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China Petroleum Processing & Petrochemical Technology 2012年第2期14卷 50-54页

作者： meng Xiuhong Gao Yuan Wang Qiang duan Linhai Key Laboratory of Petrochemical Catalytic Science and Technology Liaoning Shihua University Fushun113001 P. R. China Department of Chemistry University of Oxford Oxford OX1 3TA United Kingdom)

K2Ti2O5 and LixK2-xTi2O5 samples with varying K contents （x=0.125, 0.15, 0.3）, targeted on removal of two main environmental pollutants： PM and NOx, were synthesized by the solid state method using TiO2, KNO3 and LiOH-H2O as starting materials and were characterized by X-ray diffractometry, scanning electron microscopy, and BET. The catalytic activity of titanate catalysts on PM oxidation was evaluated using the temperature programmed oxidation （TPO） method. The test results showed that the perovskite structure of K2Ti205 was still retained after doping a small amount of Li, and the catalytic performance of LixK2-xTi2O5 had been improved significantly compared with that of K2Ti2O5. Li0.15K1.85Ti205 catalyst had the highest catalytic activity with an ignition temperature of 210℃ and a peak temperature of 290℃. The catalytic activity of both K2Ti2O5 and LixK2-xTi2O5 under intimate contact was higher than that under loose contact. When the exhaust gas flow rate was around 100 mL/min, the catalyst samples showed a highest activity. The Li doped K2Ti2O5 could be an excellent candidate for PM oxidation due to its high oxidation activity, water stability, resistance to sulfur poisoning and economical advantages.

关键词： potassium titanates diesel PM PM oxidation Li doping

Mapping of lakes in the Qinghai-Tibet Plateau from 2016 to 2021: trend and potential regularity

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International Journal of Digital Earth 2022年第1期15卷 1692-1714页

作者： Zhichong Yang Si-Bo duan Xiaoai Dai yingwei Sun meng Liu College of Earth Science Chengdu University of technologyChengduPeople’s Republic of China Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijingPeople’s Republic of China

Lakes over the Qinghai-Tibet Plateau (TP) have large quantities and areas. As an important component of fragile plateau ecosystems,these lakes have attracted increasing attention. However,owing to the limitations of technology and methods,changes in smaller lakes on the TP have received less attention. In this study,we used Google Earth Engine (GEE) with the Analysis Ready Data (ARD) preparation framework to obtain preprocessed Sentinel-1 data covering the plateau. The D-LinkNet framework was introduced to achieve lake extraction,and the lake dataset was completed from 2016 to 2021. The lake dataset showed an area accuracy of 86.49% and Intersection over Union (IoU) of 0.72-0.99 in different regions. The findings were as follows: during the study period,the TP lakes tended to be stable after increasing,with an increase in area and number of +7.6% and +14.8%. Except for the northwest TP,the other regions show the same general trend. In particular,the Tarim Basin exhibited a lake variation pattern independent of the TP. Significantly,we found frequent lake activity in the Kunlun Mountains,Qaidam Basin,Mountain Qogir,etc. Effects of the ongoing La Niña event on the TP lakes may occur in the next few years.

关键词： Sentinel-1 Qinghai-Tibet Plateau lake mapping Google Earth Engine deep learning

Classification of clustered microseismic events in a coal mine using machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第6期13卷 1256-1273页

作者： yi duan yiran Shen Ismet Canbulat Xun Luo Guangyao Si CSRIO Mineral Resources BrisbaneQLD4069Australia School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW2052Australia School of Software Shandong UniversityJinanShandong250100China

Discrimination of seismicity distributed in different areas is essential for reliable seismic risk assessment in *** machine learning has been widely applied in seismic data processing,feasibility and reliability of applying this technique to classify spatially clustered seismic events in underground mines are yet to be *** this research,two groups of seismic events with a minimum local magnitude(ML) of-3 were observed in an underground coal *** were respectively located around a dyke and the longwall ***,two types of undesired signals were also *** machine learning methods,*** forest(RF),support vector machine(SVM),deep convolutional neural network(DCNN),and residual neural network(ResNN),were used for classifying these *** results obtained based on a primary dataset showed that these seismic events could be classified with at least 91% *** DCNN using seismogram images as the inputs reached the best performance with more than 94% *** mining is a dynamic progress which could change the characteristics of seismic signals,the temporal variance in the prediction performance of DCNN was also investigated to assess the reliability of this classifier during mining.A cascaded workflow consisting of database update,model training,signal prediction,and results review was *** progressively calibrating the DCNN model,it achieved up to 99% prediction *** results demonstrated that machine learning is a reliable tool for the automatic discrimination of spatially clustered seismicity in underground mining.

关键词： Seismic event classification Clustered seismicity Machine learning Cascaded workflow Underground mining

Formation and thermal stability of amorphous Ni-Mo-P alloys

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中国有色金属学会会刊：英文版 2004年第z1期14卷 147-151页

作者： ZHANG yi MA Jun FANG Yong-kui duan Ji-guo School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China

The experimental researches on the chemical deposition of Ni-Mo-P amorphous alloys were carried out by adding Na2 MoO4 into acidic solutions. The optimum technology conditions were obtained by orthogonal design experiments. The structures and the relationship between compositions and their thermal stability were studied by energy spectrum (EC), scanning electron micrograph and X-ray diffraction spectrum. Compared with Ni-P amorphous alloys, the Ni-Mo-P amorphous alloys have high crystallization temperature and thermal stability, and the hardness reaches its peak when the annealing temperature is 500 ℃. With the increase of the heat treatment temperature, the surface morphology of the alloys changes.

关键词： chemical deposition Ni-Mo-P alloy amorphous phase crystallization