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91.
对拉脱法测量液体表面张力系数实验的原理和仪器做了简要的介绍,并着重对该实验误差的来源进行了分析探讨。 相似文献
92.
Principal component analysis of urine metabolites detected by NMR and DESI–MS in patients with inborn errors of metabolism 总被引:1,自引:0,他引:1
Pan Z Gu H Talaty N Chen H Shanaiah N Hainline BE Cooks RG Raftery D 《Analytical and bioanalytical chemistry》2007,387(2):539-549
Urine metabolic profiles of patients with inborn errors of metabolism were examined with nuclear magnetic resonance (NMR) and desorption electrospray ionization mass spectrometry (DESI-MS) methods. Spectra obtained from the study of urine samples from individual patients with argininosuccinic aciduria (ASA), classic homocystinuria (HCY), classic methylmalonic acidemia (MMA), maple syrup urine disease (MSUD), phenylketonuria (PKU) and type II tyrosinemia (TYRO) were compared with six control patient urine samples using principal component analysis (PCA). Target molecule spectra were identified from the loading plots of PCA output and compared with known metabolic profiles from the literature and metabolite databases. Results obtained from the two techniques were then correlated to obtain a common list of molecules associated with the different diseases and metabolic pathways. The combined approach discussed here may prove useful in the rapid screening of biological fluids from sick patients and may help to improve the understanding of these rare diseases. 相似文献
93.
Proximal point algorithm with errors for generalized strongly nonlinear quasivariational inclusions 总被引:1,自引:0,他引:1
丁协平 《应用数学和力学(英文版)》1998,19(7):637-643
I.IntroductionLetHbeaHibertspaceendowedwithanorm11'11andaninnerproduct',.)andC(H)bethefamilyofallnonemptycompactsubsetsofH.LetT,A:H~C(H)besetvaluedmappings,g:H~Hbeasingle-valuedmappingand9:HxH~RU{ ac}besuchthatforeachfixedyeH,9.,y):H~RUt co}isaproperconvexlowersemicontinuousfunctiononHandg(H)ndomag'Y)#oforeachyeH,ThentheproblemoffindingxeH,ueT(x)andveA(x)suchthatg(x)edomag',x)and(u~v,y~g(x))39(g(x)'x)~9(y'x)(VYeH)(l.l)iscalledthegeneralizedstronglynonlinearquasivariationalinclusio… 相似文献
94.
WANG Chunhai ZHANG Guoxiong 《Chinese Journal of Lasers》1999,8(1):39-44
1IntroductionSinglefrequencyinterferometerposesessomeimportantadvantages:availabilityofobtainingextremelystablefrequency,nofr... 相似文献
95.
Massen C. H. Swüste C. H. W. Robens E. Poulis J. A. 《Journal of Thermal Analysis and Calorimetry》1999,55(2):449-454
At the 3rd Conference on Vacuum Microbalance Techniques in Los Angeles in 1962, we suggested the use of the equation of motion
of a balance T=J+α+kα+Cα for the calculation of the unknown torque T, and the measurement for that purpose of the values of
all the other quantities in this equation. The present paper discusses the consequences of two sources of error relevant for
this method. First, the errors caused in the first and second derivatives of the deflection are considered, deduced from two
or three deflection measurements separated by small time intervals. Secondly, the consequences of the errors caused by the
uncertainties in the deflection measurements are discussed. Consideration of the two errors together leads to an optimal set
of values of parameters for the balance handling.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
96.
胡良根 《宁波大学学报(理工版)》2005,18(1):12-15
在一致凸的Banach空间中,使用了一种新的证明方法研究了渐近非膨胀映象具误差的修正Mann和Ishikawa迭代程序的收敛性问题;并且不要求定义域和值域有界,迭代系数更为简单. 相似文献
97.
98.
H. Berger 《Crystal Research and Technology》2002,37(7):716-726
The reflection curves as measured by means of the “Ω‐Scan Method” have been simulated as exactly as possible and practicable. The contributions of the collimator function for different beam geometry and of the spectral distribution are considered. The influence of the dead time of the counting unit on the fluctuations of the used high intensities is described by computer modelling. By means of the simulated curves, the theoretical statistic errors of the method, employed to the orientation determination of quartz, can be estimated and compared to the measured ones. The statistic errors due to the intensity fluctuations were found to be dominating the measuring errors. From the simulated curves also the corrections to be applied to the measuring values of the peak positions are derived. Thus, the real physical values of the orientation coordinates can be determined. 相似文献
99.
This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between
the dilution of precision (DOP) of four-dimensional (4D) calculation including satellite clock errors and ephemeris errors
and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS
shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock
errors and ephemeris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock
errors are separated in a master station with time synchronization, and all the remaining pseudo-range errors after the satellite
clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis
of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid
for GEO constellation.
Supported by the National Natural Science Foundation of China (Grant No. 10778715), the National Key Basic Research Development
Program of China (Grant No. 2007CB815502), and the Scientific Research Fund of Hunan Provincial Education Department (Grant
No. 08B039) 相似文献
100.
A. Pérez-González J. M. Vilar-Fernández W. González-Manteiga 《Annals of the Institute of Statistical Mathematics》2009,61(1):85-109
The main objective of this work is the nonparametric estimation of the regression function with correlated errors when observations
are missing in the response variable. Two nonparametric estimators of the regression function are proposed. The asymptotic
properties of these estimators are studied; expresions for the bias and the variance are obtained and the joint asymptotic
normality is established. A simulation study is also included. 相似文献