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1.
1 Introduction LetX ,YbetwoHilbertspacesandletAbeaboundedlinearoperator,i.e .,A∈B(X ,Y) .Consid ertheoperatorequationAx=y . (1)IfR(A) ,therangeofA ,isnonclosedinY ,Eq .(1)isill posed[1] .Manyimportantproblemsinappliedsci encesresultinthiskindofequations[2 ,3] .Inthispaperwec…  相似文献   

2.
INTRODUCTIONManygeneticmodelsbasedontheapproachofANOVA (analysisofvariance)weredevel opedbyFisher(1 92 5) .Someofthesemodels,e.g .NCdesignIandII(Comstocketal.,1 952 ;Hallaueretal.,1 981 ) ,diallelmodels(Yates,1 94 7;Griffing,1 956;GardnerandE berhart,1 966) ,arestillwidelyusedbypla…  相似文献   

3.
INTRODUCTIONLet{Y(t) ;-∞ <t <∞ }={Xk(t) ;-∞ <t<∞ }∞k=1 beasequenceofindepen dentOrnstein Uhlenbeck (OU)processeswithcoefficientsγk≥ 0andλk>0 ,i.e.,Xk(·)isastationary ,meanzeroGaussianprocesswithEXk(s)Xk(t) =(γk λk)exp( -λk|t-s|) ,k=1 ,2 ,… .TheprocessY(·)wasfirstintroducedbyDawson ( 1 972 )a…  相似文献   

4.
INTRODUCTIONLetZ ,N0 andNdenotethesetsofinte gers,non negativeintegersandpositiveintegers,respectively.Andletχ ={Xi} i∈Zdenotease quenceofreal valuedrandomvariablessuchthatEXi =0andEX2 i =σ2 X  i∈Z .Anyrealizationofthesequence {Xi} i∈Ziscalleda“randomscenery” .Lety ={…  相似文献   

5.
INTRODUCTIONCr4 :YAGcrystalshadbeenwidelyusedassaturableabsorbersforflashlamppumpedoscil latorandMOPAsystems (Shimonyetal.,1 995,1 996,Eichler,1 994 ,1 995,Yankov,1 994 )aswellasindiodepumpedlasers(Zayhowskietal.,1 994 ) .Theypresentedaneasywaytogen eratepassivelyQ switchedlase…  相似文献   

6.
《河北自学考试》2000,(9):33-37
Ⅰ .VocabularyandStucture (1 0 points,1 pointforeach)1 .Almosteverythingamanagerdoes  deci sions;indeed ,somesuggestthatthemanagementpro cessisdecisionmaking .[A]imposes[B]improvises[C]involves[D]indi cates2 .Astronomersandscientiststhinkthatablackholeisaregionofspace…  相似文献   

7.
INTRODUCTIONShortbowelsyndromeleadstosignificantmorbidityandispotentiallylethal,especiallywhenintestinallossisextensiveandwhenthepatientisveryyoung (Kurkchubascheetal.,1 993;Weberetal.,1 991 ;Vanderhoofetal.,1 997) .Despitetheadvancesinmedicalandsurgicaltechniquean…  相似文献   

8.
·Reviews·PhysicalandMathematicalModelingoftheArgon OxygenDecarburizationRefiningProcessofStainlessSteelWEIJi He  (1 )………………………………………………………………………………………………………·Letters·SteganographicTechniqueCapableofWithstandingRQPAnalysisWANGShuo Zhong ZHANGXin Peng ZHANG…  相似文献   

9.
INTRODUCTIONThemicrostructureofthinfilmsplaysacru cialroleinawidevarietyofphysicalprocesses.Thereareclearevidencesthatmanyphysicalpropertiesofathinfilmvarydramaticallyasitsmicrostructurechanges (Hausetal.,1 987) .Forinstance,roughsubstratescanbeusedtofabric…  相似文献   

10.
INTRODUCTIONHeterodinuclearcomplexesareofgreatinter estforthestudyofsynergisticeffectsfoundinbimetalliccatalysis(Dombek ,1 985;JnLingetal.,1 993 ;Mccollumetal.,1 996) .Moreandmoresyntheticrouteshavebeenreportedinthelastdecade(Harteretal.,1 989;Scottetal.,1 993 ;Diamondetal.…  相似文献   

11.
Image reconstruction in elecrical impedance tomography(EIT)is a highly ill-posed inverse problem,Regularization techniques must be used in order to solve the problem,In this paper,a new regularization method based on the spatial filtering theory is proposed.The new regularized reconstruction for EIT is independent of the estimation of impedance distribution,so it can be implemented more easily than the maxiumum a posteriori(MAP) method.The regularization level in our proposed method varies spatially so as to be suited to the correlation character of the object‘s impedance distribution.We implemented our regularization method with two dimensional computer simulations.The experimental results indicate that the quality of the reconstructed impedance images with the descibed regularization method based on spatial filtering theory is better than that with Tikhonov method.  相似文献   

12.
Research in regularization, as applied to structural equation modeling (SEM), remains in its infancy. Specifically, very little work has compared regularization approaches across both frequentist and Bayesian estimation. The purpose of this study was to address just that, demonstrating both similarity and distinction across estimation frameworks, while specifically highlighting more recent developments in Bayesian regularization. This is accomplished through the use of two empirical examples that demonstrate both ridge and lasso approaches across both frequentist and Bayesian estimation, along with detail regarding software implementation. We conclude with a discussion of future research, advocating for increased evaluation and synthesis across both Bayesian and frequentist frameworks.  相似文献   

13.
以多种运行模式兴办养老服务业已成为应对我国人口老龄化的有效路径.作为新型的养老服务业市场化运行模式,不管是受不同程度政策支持并已有所成型的公建民营模式、民办公助模式,抑或尚在实践探索中的以房养老这一新兴模式,俱因现行制度缺失,缺乏规范性,加之社会认识不足,其运行取向尚存在不少偏差,还面临着种种困境.为此,亟待采取针对性对策措施,特别是通过程序规制及监管强化,使其在可持续性制度建设支持下得以规范而有效的成长和运行.  相似文献   

14.
应用紧算子的奇异系统给出了迭代Tikhonov正则化子.选验选取则参数证明了迭代Tikhonov正则解具有最优的渐近收敛阶。  相似文献   

15.
为了降低迭代正则化中定尺度参数对快速收敛的敏感性、自适应地优化尺度参数并提高其去噪效果,提出了一种变尺度参数的迭代正则化去噪算法.首先,修改了经典的正则化项,并推导出尺度参数公式;然后,通过研究迭代次数与尺度参数序列的变化趋势,得到变尺度参数的初始值;最后,进行正则化去噪.数值实验表明:相对于恒定尺度参数的IRM算法,变尺度参数IRM算法比选取尺度参数偏小的IRM算法迭代次数大大减少;比选取尺度参数偏大的IRM算法去噪效果更为明显,并较好地保持了图像的细节.  相似文献   

16.
注释与参考文献是学术论著的重要组成部分,也是学术规范的有机组成部分。其规范化程度直接影响学术成果的表达和传播效果,反映文风、学风、工作作风等。注释与参考文献各有不同的功能、作用和著录方式,应予分开。要实现注释与参考文献的规范化,应在执行国家标准的基础上,切实注意一些处理细节,在实践中逐步统一规范,并建立专家和编辑严格把关制度,加强作者自律。  相似文献   

17.
公共治理:内涵 基础 途径   总被引:11,自引:0,他引:11  
公共治理,作为补充政府管理和市场调节不足应运而生的一种社会管理方式,已逐渐成为公共管理的重要理念和价值追求。它既是各国政府改革的实践总结,又是影响各国政府再造的一种全新理念。公共治理是以政府为主体、多种公私机构并存的新型社会公共事务管理模式;公共治理产生于公民社会,源自于个人领域的不断扩大;培育和建立公民社会是实现公共治理的有效途径。  相似文献   

18.
利用正则化的局部多项式预测法对logistic混沌映射时间序列进行预测,并分析了预测误差.结果显示正则化的局部多项式预测法对非线性时间序列具有良好的特性.  相似文献   

19.
Solution to impedance distribution in electrical impedance tomography (EIT) is an ill-posed nonlinear inverse problem. It is especially difficult to reconstruct an EIT image in the center area of a measured object. Tikhonov regularization with some prior information is a sound regnlarization method for static electrical impedance tomography under the condition that some true impedance distribution information is known a priori. This paper presents a direct search method (DSM) as pretreatment of image reconstruction through which one not only can construct a regularization matrix which may locate in areas of impedance change, but also can obtain an initial impedance distribution more similar to the true impedance distribution, as well as better current modes which can better distinguish the initial distribution and the true distribution. Simulation results indicate that, by using DSM, resolution in the center area of the measured object can be improved significantly.  相似文献   

20.
本文利用吉洪诺夫正则化方法 ,给出了Fourier型问题的数值解 .  相似文献   

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