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M. A. Pikin Yu. V. Nesterov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):159-165
A mathematical model for analysis of process parameters of equipment in the second circuit of nuclear power plants is presented,
and the structure of the program and principles used for analysis of the equipment are described. A mathematical model for
analysis of the deaerator and steam generator is described in detail. A computational analysis of several transitional modes,
which is made possible on the basis of the mathematical model in question, is also presented in this paper, and a comparison
is made with test data.
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Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 16–22. 相似文献
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A. V. Ivanov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(6):327-331
Successful introduction of pisciculture to reservoirs by the method of migratory fish-farm pasturing is described.
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Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, September 2007, pp. 36–40. 相似文献
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In this paper, we discuss the properties of preliminary test estimators (PTE) of the parameters of simple linear model with
measurement error (ME model) when the slope of the linear model is suspected to be zero. Expressions of the bias, MSE and
efficiencies are obtained under conditional as well as unconditional situations with known reliability coefficient. Conditional
model results are compared to the standard model without measurement error. We also provide the unconditional model analysis
in finite samples. Asymptotic theory under local alternatives is developed when the variance of measurement error or the ratio
of the variance of the model error relative to the variance of the measurement error is known. Asymptotic expressions of bias
and MSE of the estimators along with their efficiencies are obtained. In every case, it is shown that the measurement error
tend to increase the variability of the estimators compared to the estimators without measurement error. Graphs and tables
are provided to see these results and to determine optimum level of significance for minimum guaranteed efficiency.
Received October 2001
RID="*"
ID="*" A. K. Md. E. Saleh is a Distinguished Research Professor and H. M. Kim is a Ph.D. candidate in the School of Mathematics
and Statistics, Carleton University, Ottawa.
Acknowledgment. The authors gratefully acknowledge the constructive suggestion of the referees to improve the paper. The research is supported
by NSERC grant A3088. 相似文献
59.
In this paper, progressive stress accelerated life tests are considered when the lifetime of a product under use condition
follows a finite mixture of distributions. The experiment is performed when each of the components in the mixture follows
a general class of distributions which includes, among others, the Weibull, compound Weibull, power function, Gompertz and
compound Gompertz distributions. It is assumed that the scale parameter of each component satisfies the inverse power low,
the progressive stress is directly proportional to time and the cumulative exposure model for the effect of changing stress
holds. Based on type-I censoring, the maximum likelihood estimates (MLEs) of the parameters under consideration are obtained.
A special attention is paid to a mixture of two Rayleigh components. Simulation results are carried out to study the precision
of the MLEs and to obtain confidence intervals for the parameters involved. 相似文献
60.
Jarl K. Kampen 《Quality and Quantity》2007,41(6):793-813
A comparison is given of (ordinal) measures of trust in government institutions that were collected with the aim of facilitating
comparisons between different modes and contexts of data collection. Statistical analyses reveal that the mode effect could
amount upto a 10% change of item nonresponse and a 9% change of the level of trust, whereas the context effect could lead
upto a 19% change of the bivariate associations of trust. The observed changes of both measures of central tendency and of
associations affect conclusions of social scientific research in isolated studies, which implies that comparative studies
are seriously hampered by bias related to mode and context, two sources of obscurity adding to the two other threats which
are differences of sample source and differences of question phrasing. 相似文献