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The paper presents a new approach to model validation and fault diagnosis problems for a class of uncertain systems in which the uncertainty is described by an integral quadratic constraint. The new approach is developed by applying methods from linear quadratic optimal control theory. This leads to a method for model validation and fault diagnosis which is based around a robust Kalman filter type structure. 相似文献
233.
G. Srinubabu K. Jaganbabu B. Sudharani K. Venugopal G. Girizasankar J. V. L. N. S. Rao 《Chromatographia》2006,64(1-2):95-100
A rapid and sensitive RP-HPLC method with UV detection for routine control of pramipexole in tablets was developed. Chromatography
was performed with mobile phase containing a mixture of acetonitrile/phosphate buffer (60/40; v/v) with a flow rate of 0.8
mL min−1. Quantitation was accomplished with the internal standard method; the procedure was validated by linearity (correlation coefficient
= 0.99892), accuracy, robustness and intermediate precision. Limit of quantitation and limit of detection were found to be
4.5 μg and 1.4 μg respectively, which indicates the method is highly sensitive. Experimental design was used during validation
to calculate method robustness and intermediate precision, for robustness test three factors were considered; percentage v/v of acetonitrile, flow rate and pH; an increase in the flow rate results in a decrease of concentration found of the drug,
while the percentage of organic modifier and temperature have no important effect on the response. For intermediate precision
measure the considered variables were: analyst, equipment, days and obtained RSD value (0.56%, n=24) which indicated a good precision of the analytical method. The method was found to be applicable for determination of
the drug in tablet formulations and the results of the developed method were compared with those of the UV spectrophotometric
method to access the active pramipexole content.
Revised: 13 March and 25 April 2006 相似文献
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A previously established model of a system of series-coupled columns is implemented for the experimental investigation of non-thermodynamic contributions to the retention time in systems of two series-coupled columns. The results show excellent agreement between theory and experiment and also stresses the importance of non-thermodynamic contributions to retention times. 相似文献
238.
Important questions exist regarding the quality of force fields used in molecular dynamics (MD) simulations and their interoperable use with other available MD implementations. NAMD is one of the most efficient and scalable parallel molecular dynamics codes for large-scale biomolecular simulations in the open source domain. It is the aim of this article to analyze and compare the dynamics of a benchmark DNA dodecamer d(CTTTTGCAAAAG)2 system, including its binding to a specific drug molecule arising from the use of various simulation protocols in NAMD using Amber98, with the dynamics arising from simulations of the same dodecamer using Amber98 in the AMBER package, one of the most well-established simulation codes for nucleic acids. Based upon a set of validation benchmarks, the details of which are discussed, we find that nucleic acid simulations using NAMD give meaningful results and that the essential features of the resulting dynamics are similar to those arising from the AMBER package. This sets the stage for reliable large-scale simulations of nucleic acids using NAMD. 相似文献
239.
Validation and quality control of methylmercury determinations by means of capillary electrophoresis 总被引:1,自引:0,他引:1
Antonia Maria Carro Diaz R. A. Lorenzo-Ferreira R. Cela-Torrijos 《Mikrochimica acta》1996,123(1-4):73-86
Methyl-Hg is one of the most dangerous pollutants in the environment. It is highly toxic and accumulates through the food chain. Tuna fish especially tends to concentrate Hg in the form of methyl-Hg. Quality assurance is a well established routine in analytical laboratories to control the variability of analytical results and to maintain adequate stability, detection power and reproducibility. Capillary electrophoresis (CE) has shown in recent years powerful capabilities for the resolution and analysis of very complex samples. The high resolution and peak capacity characteristics of this technique could be used favourably in speciation studies of organo-Hg compounds. Since the time needed for separation is usually very short in this technique, it lends itself to routine analysis. The application of quality control approaches in the analysis of methyl-Hg in tuna freeze-dried materials using CE is reported. 相似文献
240.