An iterative algorithm in potential-field inversion

1　Principle and MethodAll the problems of potential- field inversioncan be concluded that of solving nonlinear functionas follows:b =f( x) ( 1 )where x =( x1,x2 ,… .xn) T,xj( j =1 ,2 ,… ,n)indicate geometricparameters and physical parame-ters of the object;b=( b1,b2 ,… ,bm) T,bi( i=1 ,2 ,… ,m) indicate potential- field measurements.Main algorithms for expression( 1 ) are leastsquare method ( include damping least squaremethod ) ,gradient method ( conjugate gradientmethod and variable met…     

On the Generalizations of Hilbert＇s Inequality

In this paper, by employing a refined Cauchy＇s inequality, some strengthened Hilbert＇s inequality with parameter A, B,λ, are further improved.     

Stability and Instability of Solution for a Class of Nonlinear Differential Equations

1　ＩｎｔｒｏｄｕｃｔｉｏｎＩｎＲｅｆ.〔1〕 ｔｈｅａｓｙｍｐｔｏｔｉｃｓｔａｂｉｌｉｔｙｏｆｎｏｎｌｉｎｅａｒｓｌｏｗｌｙｃｈａｎｇｉｎｇｓｙｓｔｅｍｈａｓｂｅｅｎｄｉｓｃｕｓｓｅｄ .ＩｎＲｅｆ.〔2〕ｔｈｅｉｎｓｔａｂｉｌｉｔｙｏｆｓｏｌｕｔｉｏｎｆｏｒｔｈｅｔｈｉｒｄｏｒｄｅｒｌｉｎｅａｒｄｉｆ ｆｅｒｅｎｔｉａｌｅｑｕａｔｉｏｎｗｉｔｈｖａｒｉｅｄｃｏｅｆｆｉｃｉｅｎｔｈａｓｂｅｅｎｄｉｓ ｃｕｓｓｅｄ .Ｉｎｔｈｉｓｐａｐｅｒ,ｗｅｈａｖｅｄｉｓｃｕｓｓｅｄｓｔａｂｌｉｌｉｔｙａｎｄｉｎｓｔａ…     

Hybrid Method: Review, Modularization and Application

1　IntroductionDuetothehighcostsofsurvey-basedmodelsandtheinherentinaccuracyofnon-surveymodels,hybridmodelsarebeingusedextensivelyinthepracticeofconstructingInput-Output(IO)tables.Thetrendtowardhybridmodelsisnatural.Hybridmodel,orcalledpartial-survey...     

STUDY OF KINETIC ANALYTICAL METHOD BASED ON CATALYTIC REACTIONS

In this thesis a reviwe is presented for the advances of catalytic spec trophotometric method, three new catalytic reaction systems were presented, and its rela live catalytic spectrophotometric methods have been established by flow injection tech nique. Particulary the relative chemometric methods and theories were used in the field of kinetic - catalytic analysis, in order to solve the problems of multicomponents analysis.     

工程项目的施工成本控制研究

本文首先阐述工程项目成本控制重要性,然后简述成本控制应遵循的原则,最后分析和研究了施工企业项目成本控制的方法。     

基于兼并引物的PCR扩增特定基因的效果比较

根据NCBI上的DNA拓扑异构酶Ⅱ基因序列设计兼并引物,采用常规PCR、降落PCR、巢式PCR三种方法扩增糙皮侧耳和阿魏侧耳的拓扑异构酶Ⅱ部分基因序列,比较三种方法扩增效果的特异性、灵敏度.结果表明,巢式PCR的灵敏度和特异性都优于常规PCR和降落PCR,并且巢式PCR的灵敏度是常规PCR灵敏度的100倍以上,更加适合兼并引物扩增.这对利用兼并引物获取特异基因具有指导意义.     

华山松不同部位DNA提取方法比较研究

获得高质量的DNA通常是开展分子水平研究的关键一步.采用经典CTAB法、改良CTAB法、简易CTAB法、SDS微量法及Zigenhagen法对华山松的茎、叶及胚乳的DNA进行提取,并进行琼脂糖凝胶电泳检测、紫外分光光度计分析和标准差及标准误分析,结果表明:对于华山松针叶DNA提取,改良CTAB法提取DNA浓度适中,标准差和标准误最小,方法稳定性好;对于华山松茎段DNA提取,Zigenhagen法提取DNA浓度高,纯度好,标准差和标准误最小,方法的稳定性最好;对于华山松胚乳DNA提取,简易CTAB法提取的DNA浓度最高,纯度最好,标准差和标准误最小,方法的稳定性最好.这也说明对于同一植物的不同部位DNA的提取要采用不同的方法,需要在实践中加以摸索,获得最大的提取效果.     

ON INDEFINITE SUBLINEAR ELLIPTIC EQUATIONS

1.IntroductionLetnCRN,N23,beasmoothboundeddomainandconsiderthesemilinearellipticequationswhereatbELoc(Q),AERIisaparameter.Itisasimplifiedmodelforsomeproblemsinpopulationdynamicsandinreaction-diffusionprocessess(seethereferencesof[1]).Bytheresultsof[...