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Nonlinear　Characteristics　of　Systems　and　Its　Application　in　Urban　planning　DSS

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Journal of Systems engineering and Electronics 1996年第4期7卷 57-64页

作者： Wang Zhe & Gu peiliang(Institute of engineering, Tianjin University, p.r.china) Institute of engineering Tianjin University P.R. China

This paper is devoted to analyzing nonlinear characteristics of complex systems. Since traditional linear system methods need to be improved, a nonlinear computational mathematics methods should be introduced to system engineering researches. Due to the lack of complete nonlinear theory, we suggest human intelligence be combined with calculating capacity of ***, a tentative ideal on an urban planning DSS with man-computer integration is proposed.

关键词： Nonlinear System engineering DSS Urban planning.

preparation and microstructure of CuO-CoO-MnO/SiO2 nanocomposite aerogels and xerogels as catalyst carriers

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progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3,Qian-yi JIA~4,Hong-sheng LI~4 1.college of Light Industry,Hebei United University,Tangshan 063000,china 2.college of Chemical engineering,Hebei United University,Tangshan 063009,china 3.college of printing and packaging engineering,Beijing Institute of Graphic Communication,Beijing 102600,china 4.college of Materials Science and engineering,Hebei United University,Tangshan 063009,china [a] college of Light Industry Hebei United University Tangshan 063000 China [b] college of Chemical engineering Hebei United University Tangshan 063009 China [c] college of printing and packaging engineering Beijing Institute of Graphic Communication Beijing 102600 China [d] college of Materials Science and engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XrD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2nanocomposite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4 nm,a specific surface area of 384.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2composite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2nanocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

Seasonal variations and bioavailability of inorganic phosphorus in soils of Yeyahu Wetland in Beijing,china

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International Journal of Sediment research 2011年第2期26卷 181-192页

作者： ZHANG Jing,LI Min,LIU Shuang,LIU Yujin,ZHANG Liqiang,CAO Qi,and SUN Dezhi 1 ph.D.student,~ 2 Assoc,prof,~(3,6) Master,~7 prof,college of Environmental Science and engineering,Beijing Forestry University,Beijing,p.r.china,100083 ~(4,5) Senior Engineer,Beijing Yanqing Yeyahu Wetland Nature reserve,Beijing,p.r.china,102101 [a]ph.D. student college of Environmental Science and engineering Beijing Forestry University Beijing P.R. China 100083 [b]Assoc. Prof. College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [c]Master College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [f]Master College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [g]prof. College of Environmental Science and Engineering Beijing Forestry University Beijing P.R. China 100083 [d]Senior Engineer Beijing Yanqing Yeyahu Wetland Nature Reserve Beijing P.R. China 102101 [e]Senior Engineer Beijing Yanqing Yeyahu Wetland Nature Reserve Beijing P.R. China 102101

phosphorus(p) in soils has an important influence on the development and productivity of wetland. The objective of this study was to investigate the distribution,bioavailability and seasonal variations of inorganic phosphorus(Ip) in soils of Yeyahu *** results showed that the concentration of Ca-bound p(Ca-p) remained the main occurrence in all Ip fractions despite the season,at the same time the Al-bound p(Al-p) was always the lowest Ip fraction despite the ***-p and Fe-bound p (Fe-p) concentration were all reached the highest value in May and the lowest in November,which was opposite to the occluded p(Oc-p) *** notable higher Oc-p concentration in November observed in this study was probably due to the decomposition of plants and the subsequently releasing of oxides to ***-p didn’t change much with season *** p(Ex-p) and Oc-p were all positively correlated with soil moisture content and organic matter content,but Al-p was negatively correlated with these two soil *** a stable form,Ca-p was not associated with soil ***-p,Fe-p and Ca-p might contribute to the storage of p in studied wetland with the principle component analysis *** concentration rank order of the bio-available p in soils was generally as follows:Olsen-p > Algal available p(AAp) > Water soluble p(WSp) > readily desorbed p(rDp).Olsen-p was positively correlated with Ex-p and Oc-p,and it was thought to be a more suitable indicator for bio-available p in soils.

关键词： Inorganic phosphorus fractions Distribution Bioavailability Seasonal variations

Mixed boundary conditions for piezoelectric plates

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Science china(physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU Sipeng 2 &ZHAO BaoSheng 3 1college of Science,china Agricultural University,Beijing 100083,china 2college of engineering,Ocean University of china,Qingdao 266071,china 3 School of Mechanical engineering,University of Science and Technology of Liaoning,Anshan 114044,china college of Science China Agricultural University Beijing 100083 China college of engineering Ocean University of China Qingdao 266071 China School of Mechanical engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Characteristics of Ore-Forming Fluids of Gold Deposits in Daqingshan District,Inner Mongolia,china

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 77-82页

作者： Jiuhua Xu YulingXie Dayi Qian rufu Dine Jianping Li (resource engineering School, University of Science and Technology Beijha Beijing 100083, china) (china University of Geosciences, Beijing 100083, china) resource engineering School University of Science and Technology Beijing Beijing 100083 China china University of Geosciences Beijing 100083 China

***-weststrikingductileshearzonewithinagreelt,***:(1)pyrite-quartz,(2)quartz-pyrite,(3)polymetallicsulfidesand(4)***-bearingveinsarenativegold,electrum,pyrite,chalcopyriteandgalena,buttheganguemineralsaremainlyquartz,... 详细信息

ract>***-weststrikingductileshearzonewithinagreelt,***:(1)pyrite-quartz,(2)quartz-pyrite,(3)polymetallicsulfidesand(4)***-bearingveinsarenativegold,electrum,pyrite,chalcopyriteandgalena,buttheganguemineralsaremainlyquartz,secondarilysericite,***,silicification,***-formingfluidswerelowinsalinitieandhighinCO2content,MeasuredδDoffluidinclusionsinquartzfromtheoreveinsrangesfrom-65‰to-104‰,butδ18Oquartzfrom10.0‰to12.8‰.Thesedatashowthatthewaterinhydrothermalfluidprecipitatingtheorebodiescouldhavebeenmainlymagmaticwaterandmetamorphicwaterbutlocalmeteoricwatermighttakepartinthelatemineralization.δ13Cfromfl

关键词： fluid inclusions isotope composition gold deposit Daqingshan area

Boundary conditions for the bending of a piezoelectric beam

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Science china(physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU Sipeng2 & ZHAO BaoSheng3 1 college of Science, china Agricultural University, Beijing 100083, china 2 college of engineering, Ocean University of china, Qingdao 266071, china 3 School of Mechanical engineering, University of Science and Technology Liaoning, Anshan 114044, china 1. college of Science China Agricultural University Beijing 100083 China 2. college of engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

An Optimal replacement policy for a System with Finite Spares

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Journal of Systems engineering and Electronics 1999年第3期10卷 76-81页

作者： Zhao Jianmin(Shijiazhuang Mechanical engineering college, 050003, p. r. china )Zhao JianhuaShijiazhuang Education college, 050000, p. r. china Shijiazhuang Mechanical engineering college 050003 P. R. China Shijiazhuang Education college 050000 P. R. China

This paper develops a new replacement policy for a system with multiple spare *** optimal replacement period is determined by maximizing the mean time to failure of the *** show that there exists a finite and unique optimal replacement period T for units with strictly increasing failure rates. We also proof that the optimal repIacement period for a system with spares is decreasing in k. Furthermore, an algorithm is presented to get the optimal replacement period and a numerical example is given to illustrate the result. with strictly

关键词： replacement Optimization Spare

producing Calcium-Bearing Mullite Thermal-Insulating refractories by Kyanite

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 50-53页

作者： Wen Ni (resources engineering School, University of Science and Technology Beijing, Beijing 100083, china) resources engineering School University of Science and Technology Beijing Beijing 100083 China

To improve the physical properties, a series of experiments have been camed out to produce calcium-bearing mullite thermal-insulating refractories by using kyanite as major raw materials. The experiments were carried out by a foaming technique and using white cement as a combing agent. The results show that the calcium-bearing mullite refractory has much better physical properhes than traditional clay refractory and high-alumina refractory.

关键词： mullite thermal-insulating refractory kyanite

Stability Analysis of DC Microgrid Clusters Based on Step-by-step System Matrix Building Algorithm

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Journal of Modern power Systems and Clean Energy 2024年第3期12卷 900-912页

作者： K.Jithin N.Mayadevi r.Hari Kumar V.p.Mini the Department of Electrical engineering College of Engineering TrivandrumAPJ Abdul Kalam Technological University(APJAKTU)ThiruvananthapuramIndia

DC microgrids(DCMGs)are made up of a network of sources and loads that are connected by a number of power electronic converters(pECs).The increase in the number of these pECs instigates major concerns in system *** interconnecting the microgrids to form a cluster,the system stability must be *** paper proposes a novel stepby-step system matrix building(SMB)algorithm to update the system matrix of an existing DCMG cluster when a new microgrid is added to the cluster through a distribution *** stability of the individual DCMGs and the DCMG cluster is analyzed using the eigenvalue ***,the particle swarm optimization(pSO)algorithm is used to retune the controller gains if the newly formed cluster is not *** simulation of the DCMG cluster is carried out in MATLAB/Simulink environment to test the proposed *** results are also validated using the Op4510 real-time simulator(rTS).

关键词： Converter DC microgrid cluster eigenvalue interconnection particle swarm optimization system stability system matrix