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91.
Singular Points Near an X_0-breaking Double Singular Fold Point in Z_2-symmetric Nonlinear Equations
SingularPointsNearanX_0-breakingDoubleSingularFoldPointinZ_2-symmetricNonlinearEquationsSuYi(苏毅)andWuwei(吴微)(DepartmentofMathe... 相似文献
92.
Evald Übi 《Central European Journal of Mathematics》2007,5(2):373-385
The system of inequalities is transformed to the least squares problem on the positive ortant. This problem is solved using
orthogonal transformations which are memorized as products. Author’s previous paper presented a method where at each step
all the coefficients of the system were transformed. This paper describes a method applicable also to large matrices. Like
in revised simplex method, in this method an auxiliary matrix is used for the computations. The algorithm is suitable for
unstable and degenerate problems primarily.
相似文献
93.
多重经济增长路径,多重稳态解和分歧 总被引:1,自引:0,他引:1
蔡东汉 《数学物理学报(A辑)》1998,18(3):348-354
该文给出一个具有可解内生生育率的Cass-Koopmans(C-K)经济增长模型.证明参数满足时,模型存在多重经济增长路径和多重稳态解;当时,经济增长路径和稳态解唯一,即描述模型的微分动力系统出现分歧.文中讨论了多重经济增长路径的几何形态、位置关系和主要结果的经济意义. 相似文献
94.
The quaternary chalcogeno halides AgHgSI, AgHgSBr and CuHgSI have been synthesized by annealing mixtures of silver (copper) halides and mercury sulphide. AgHgSI decomposes peritectoidally at 593±3 K and crystallizes in the orthohombic system with lattice constants ofa=772.3 (3),b=847.7 (3) andc=707.3 (3) pm. The phase diagram AgI-HgS resembles the AgI-Ag2S system closely. Contrary to the literature the only stable compound in this system is AgHgSI. The previously mentioned Ag2HgSI2 is metastable. The reported compound Ag2HgSBr2 could not be synthesized. The substitution of Hg2+ by Cd2+ in CuHgSI leads to a red phase Cu2Cd3S2I4 which crystallizes in the wurtzite type structure with lattice parameters ofa=424.7 (1) andc=695.2 (1) pm. 相似文献
95.
用系统工程学的观点, 重新认识矿山岩体工程的特点。建立矿山岩体工程稳定性的系统的概念。提出地质模型、设计模型、施工模型的构思, 使工程地质、设计、施工三者密切结合, 共同解决矿山岩体工程稳定问题。通过动态监测和信息反馈, 在工程施工的动态过程中不断地获得新的认识, 以便对工程实施做出新的决策。 相似文献
96.
Christian Wenz Coral Barbas Ángeles López‐Gonzálvez Antonia Garcia Fernando Benavente Victoria Sanz‐Nebot Tim Blanc Gordon Freckleton Philip Britz‐McKibbin Meera Shanmuganathan Francois de l′Escaille Johann Far Rob Haselberg Sean Huang Carolin Huhn Martin Pattky David Michels Si Mou Feng Yang Christian Neusuess Nora Tromsdorf Edward E.K. Baidoo Jay D. Keasling SungAe Suhr Park 《Journal of separation science》2015,38(18):NA-NA
A collaborative study on the robustness and portability of a capillary electrophoresis‐mass spectrometry method for peptide mapping was performed by an international team, consisting of 13 independent laboratories from academia and industry. All participants used the same batch of samples, reagents and coated capillaries to run their assays, whereas they utilized the capillary electrophoresis‐mass spectrometry equipment available in their laboratories. The equipment used varied in model, type and instrument manufacturer. Furthermore, different types of sheath‐flow capillary electrophoresis–mass spectrometry interfaces were used. Migration time, peak height and peak area of ten representative target peptides of trypsin‐digested bovine serum albumin were determined by every laboratory on two consecutive days. The data were critically evaluated to identify outliers and final values for means, repeatability (precision within a laboratory) and reproducibility (precision between laboratories) were established. For relative migration time the repeatability was between 0.05 and 0.18% RSD and the reproducibility between 0.14 and 1.3% RSD. For relative peak area repeatability and reproducibility values obtained were 3–12 and 9–29% RSD, respectively. These results demonstrate that capillary electrophoresis‐mass spectrometry is robust enough to allow a method transfer across multiple laboratories and should promote a more widespread use of peptide mapping and other capillary electrophoresis‐mass spectrometry applications in biopharmaceutical analysis and related fields. 相似文献
97.
Yuanzhong Yang Reinhard I. BoysenJamil Chowdhury Asif AlamMilton T.W. Hearn 《Analytica chimica acta》2015
In this study, the advantages of carrying out the analysis of peptides and tryptic digests of proteins under gradient elution conditions at pH 6.5 by reversed-phase liquid chromatography (RP-HPLC) and in-line electrospray ionisation mass spectrometry (ESI-MS) are documented. For these RP separations, a double endcapped, bidentate anchored n-octadecyl wide pore silica adsorbent was employed in a capillary column format. Compared to the corresponding analysis of the same peptides and protein tryptic digests using low pH elution conditions for their RP-HPLC separation, this alternative approach provides improved selectivity and more efficient separation of these analytes, thus allowing a more sensitive identification of proteins at different abundance levels, i.e. more tryptic peptides from the same protein could be confidently identified, enabling higher sequence coverage of the protein to be obtained. This approach was further evaluated with very complex tryptic digests derived from a human plasma protein sample using an online two-dimensional (2D) strong cation-exchange (SCX)-RP-HPLC-ESI-MS/MS system. Again, at pH 6.5, with mobile phases of different compositions, improved chromatographic selectivities were obtained, concomitant with more sensitive on-line electrospray ionisation tandem mass spectrometric (ESI-MS/MS) analysis. As a consequence, more plasma proteins could be confidently identified, highlighting the potential of these RP-HPLC methods with elution at pH 6.5 to extend further the scope of proteomic investigations. 相似文献
98.
The aim of this paper is to present an efficient analytical and numerical procedure for solving systems of nonlinear Fredholm–Volterra integral equations of the Hammerstein type with the aid of fixed point techniques and the usual Schauder basis in an adequate Banach space. 相似文献
99.
100.
Iterated Function System (IFS) models have been used to represent discrete sequences where the attractor of the IFS is self-affine
or piece-wise self-affine in R
2 or R
3 (R is the set of real numbers). In this paper, the piece-wise hidden-variable fractal model is extended from R
3 to R
n (n is an integer greater than 3), which is called the high-dimensional piece-wise hidden-variable fractal model. This new model
uses a “mapping partial derivative” and a constrained inverse algorithm to identify the model parameters. The model values
depend continuously on all the hidden variables. Therefore, the result is very general. 相似文献